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/*
* Copyright (C) 2014 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "code_generator_arm64.h"
#include "arch/arm64/asm_support_arm64.h"
#include "arch/arm64/instruction_set_features_arm64.h"
#include "art_method.h"
#include "base/bit_utils.h"
#include "base/bit_utils_iterator.h"
#include "class_table.h"
#include "code_generator_utils.h"
#include "compiled_method.h"
#include "entrypoints/quick/quick_entrypoints.h"
#include "entrypoints/quick/quick_entrypoints_enum.h"
#include "gc/accounting/card_table.h"
#include "heap_poisoning.h"
#include "intrinsics.h"
#include "intrinsics_arm64.h"
#include "linker/linker_patch.h"
#include "lock_word.h"
#include "mirror/array-inl.h"
#include "mirror/class-inl.h"
#include "offsets.h"
#include "thread.h"
#include "utils/arm64/assembler_arm64.h"
#include "utils/assembler.h"
#include "utils/stack_checks.h"
using namespace vixl::aarch64; // NOLINT(build/namespaces)
using vixl::ExactAssemblyScope;
using vixl::CodeBufferCheckScope;
using vixl::EmissionCheckScope;
#ifdef __
#error "ARM64 Codegen VIXL macro-assembler macro already defined."
#endif
namespace art {
template<class MirrorType>
class GcRoot;
namespace arm64 {
using helpers::ARM64EncodableConstantOrRegister;
using helpers::ArtVixlRegCodeCoherentForRegSet;
using helpers::CPURegisterFrom;
using helpers::DRegisterFrom;
using helpers::FPRegisterFrom;
using helpers::HeapOperand;
using helpers::HeapOperandFrom;
using helpers::InputCPURegisterAt;
using helpers::InputCPURegisterOrZeroRegAt;
using helpers::InputFPRegisterAt;
using helpers::InputOperandAt;
using helpers::InputRegisterAt;
using helpers::Int64ConstantFrom;
using helpers::IsConstantZeroBitPattern;
using helpers::LocationFrom;
using helpers::OperandFromMemOperand;
using helpers::OutputCPURegister;
using helpers::OutputFPRegister;
using helpers::OutputRegister;
using helpers::QRegisterFrom;
using helpers::RegisterFrom;
using helpers::SRegisterFrom;
using helpers::StackOperandFrom;
using helpers::VIXLRegCodeFromART;
using helpers::WRegisterFrom;
using helpers::XRegisterFrom;
// The compare/jump sequence will generate about (1.5 * num_entries + 3) instructions. While jump
// table version generates 7 instructions and num_entries literals. Compare/jump sequence will
// generates less code/data with a small num_entries.
static constexpr uint32_t kPackedSwitchCompareJumpThreshold = 7;
// Reference load (except object array loads) is using LDR Wt, [Xn, #offset] which can handle
// offset < 16KiB. For offsets >= 16KiB, the load shall be emitted as two or more instructions.
// For the Baker read barrier implementation using link-generated thunks we need to split
// the offset explicitly.
constexpr uint32_t kReferenceLoadMinFarOffset = 16 * KB;
// Flags controlling the use of link-time generated thunks for Baker read barriers.
constexpr bool kBakerReadBarrierLinkTimeThunksEnableForFields = true;
constexpr bool kBakerReadBarrierLinkTimeThunksEnableForArrays = true;
constexpr bool kBakerReadBarrierLinkTimeThunksEnableForGcRoots = true;
// Some instructions have special requirements for a temporary, for example
// LoadClass/kBssEntry and LoadString/kBssEntry for Baker read barrier require
// temp that's not an R0 (to avoid an extra move) and Baker read barrier field
// loads with large offsets need a fixed register to limit the number of link-time
// thunks we generate. For these and similar cases, we want to reserve a specific
// register that's neither callee-save nor an argument register. We choose x15.
inline Location FixedTempLocation() {
return Location::RegisterLocation(x15.GetCode());
}
inline Condition ARM64Condition(IfCondition cond) {
switch (cond) {
case kCondEQ: return eq;
case kCondNE: return ne;
case kCondLT: return lt;
case kCondLE: return le;
case kCondGT: return gt;
case kCondGE: return ge;
case kCondB: return lo;
case kCondBE: return ls;
case kCondA: return hi;
case kCondAE: return hs;
}
LOG(FATAL) << "Unreachable";
UNREACHABLE();
}
inline Condition ARM64FPCondition(IfCondition cond, bool gt_bias) {
// The ARM64 condition codes can express all the necessary branches, see the
// "Meaning (floating-point)" column in the table C1-1 in the ARMv8 reference manual.
// There is no dex instruction or HIR that would need the missing conditions
// "equal or unordered" or "not equal".
switch (cond) {
case kCondEQ: return eq;
case kCondNE: return ne /* unordered */;
case kCondLT: return gt_bias ? cc : lt /* unordered */;
case kCondLE: return gt_bias ? ls : le /* unordered */;
case kCondGT: return gt_bias ? hi /* unordered */ : gt;
case kCondGE: return gt_bias ? cs /* unordered */ : ge;
default:
LOG(FATAL) << "UNREACHABLE";
UNREACHABLE();
}
}
Location ARM64ReturnLocation(DataType::Type return_type) {
// Note that in practice, `LocationFrom(x0)` and `LocationFrom(w0)` create the
// same Location object, and so do `LocationFrom(d0)` and `LocationFrom(s0)`,
// but we use the exact registers for clarity.
if (return_type == DataType::Type::kFloat32) {
return LocationFrom(s0);
} else if (return_type == DataType::Type::kFloat64) {
return LocationFrom(d0);
} else if (return_type == DataType::Type::kInt64) {
return LocationFrom(x0);
} else if (return_type == DataType::Type::kVoid) {
return Location::NoLocation();
} else {
return LocationFrom(w0);
}
}
Location InvokeRuntimeCallingConvention::GetReturnLocation(DataType::Type return_type) {
return ARM64ReturnLocation(return_type);
}
// NOLINT on __ macro to suppress wrong warning/fix (misc-macro-parentheses) from clang-tidy.
#define __ down_cast<CodeGeneratorARM64*>(codegen)->GetVIXLAssembler()-> // NOLINT
#define QUICK_ENTRY_POINT(x) QUICK_ENTRYPOINT_OFFSET(kArm64PointerSize, x).Int32Value()
// Calculate memory accessing operand for save/restore live registers.
static void SaveRestoreLiveRegistersHelper(CodeGenerator* codegen,
LocationSummary* locations,
int64_t spill_offset,
bool is_save) {
const uint32_t core_spills = codegen->GetSlowPathSpills(locations, /* core_registers */ true);
const uint32_t fp_spills = codegen->GetSlowPathSpills(locations, /* core_registers */ false);
DCHECK(ArtVixlRegCodeCoherentForRegSet(core_spills,
codegen->GetNumberOfCoreRegisters(),
fp_spills,
codegen->GetNumberOfFloatingPointRegisters()));
CPURegList core_list = CPURegList(CPURegister::kRegister, kXRegSize, core_spills);
unsigned v_reg_size = codegen->GetGraph()->HasSIMD() ? kQRegSize : kDRegSize;
CPURegList fp_list = CPURegList(CPURegister::kVRegister, v_reg_size, fp_spills);
MacroAssembler* masm = down_cast<CodeGeneratorARM64*>(codegen)->GetVIXLAssembler();
UseScratchRegisterScope temps(masm);
Register base = masm->StackPointer();
int64_t core_spill_size = core_list.GetTotalSizeInBytes();
int64_t fp_spill_size = fp_list.GetTotalSizeInBytes();
int64_t reg_size = kXRegSizeInBytes;
int64_t max_ls_pair_offset = spill_offset + core_spill_size + fp_spill_size - 2 * reg_size;
uint32_t ls_access_size = WhichPowerOf2(reg_size);
if (((core_list.GetCount() > 1) || (fp_list.GetCount() > 1)) &&
!masm->IsImmLSPair(max_ls_pair_offset, ls_access_size)) {
// If the offset does not fit in the instruction's immediate field, use an alternate register
// to compute the base address(float point registers spill base address).
Register new_base = temps.AcquireSameSizeAs(base);
__ Add(new_base, base, Operand(spill_offset + core_spill_size));
base = new_base;
spill_offset = -core_spill_size;
int64_t new_max_ls_pair_offset = fp_spill_size - 2 * reg_size;
DCHECK(masm->IsImmLSPair(spill_offset, ls_access_size));
DCHECK(masm->IsImmLSPair(new_max_ls_pair_offset, ls_access_size));
}
if (is_save) {
__ StoreCPURegList(core_list, MemOperand(base, spill_offset));
__ StoreCPURegList(fp_list, MemOperand(base, spill_offset + core_spill_size));
} else {
__ LoadCPURegList(core_list, MemOperand(base, spill_offset));
__ LoadCPURegList(fp_list, MemOperand(base, spill_offset + core_spill_size));
}
}
void SlowPathCodeARM64::SaveLiveRegisters(CodeGenerator* codegen, LocationSummary* locations) {
size_t stack_offset = codegen->GetFirstRegisterSlotInSlowPath();
const uint32_t core_spills = codegen->GetSlowPathSpills(locations, /* core_registers */ true);
for (uint32_t i : LowToHighBits(core_spills)) {
// If the register holds an object, update the stack mask.
if (locations->RegisterContainsObject(i)) {
locations->SetStackBit(stack_offset / kVRegSize);
}
DCHECK_LT(stack_offset, codegen->GetFrameSize() - codegen->FrameEntrySpillSize());
DCHECK_LT(i, kMaximumNumberOfExpectedRegisters);
saved_core_stack_offsets_[i] = stack_offset;
stack_offset += kXRegSizeInBytes;
}
const uint32_t fp_spills = codegen->GetSlowPathSpills(locations, /* core_registers */ false);
for (uint32_t i : LowToHighBits(fp_spills)) {
DCHECK_LT(stack_offset, codegen->GetFrameSize() - codegen->FrameEntrySpillSize());
DCHECK_LT(i, kMaximumNumberOfExpectedRegisters);
saved_fpu_stack_offsets_[i] = stack_offset;
stack_offset += kDRegSizeInBytes;
}
SaveRestoreLiveRegistersHelper(codegen,
locations,
codegen->GetFirstRegisterSlotInSlowPath(), true /* is_save */);
}
void SlowPathCodeARM64::RestoreLiveRegisters(CodeGenerator* codegen, LocationSummary* locations) {
SaveRestoreLiveRegistersHelper(codegen,
locations,
codegen->GetFirstRegisterSlotInSlowPath(), false /* is_save */);
}
class BoundsCheckSlowPathARM64 : public SlowPathCodeARM64 {
public:
explicit BoundsCheckSlowPathARM64(HBoundsCheck* instruction) : SlowPathCodeARM64(instruction) {}
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
LocationSummary* locations = instruction_->GetLocations();
CodeGeneratorARM64* arm64_codegen = down_cast<CodeGeneratorARM64*>(codegen);
__ Bind(GetEntryLabel());
if (instruction_->CanThrowIntoCatchBlock()) {
// Live registers will be restored in the catch block if caught.
SaveLiveRegisters(codegen, instruction_->GetLocations());
}
// We're moving two locations to locations that could overlap, so we need a parallel
// move resolver.
InvokeRuntimeCallingConvention calling_convention;
codegen->EmitParallelMoves(locations->InAt(0),
LocationFrom(calling_convention.GetRegisterAt(0)),
DataType::Type::kInt32,
locations->InAt(1),
LocationFrom(calling_convention.GetRegisterAt(1)),
DataType::Type::kInt32);
QuickEntrypointEnum entrypoint = instruction_->AsBoundsCheck()->IsStringCharAt()
? kQuickThrowStringBounds
: kQuickThrowArrayBounds;
arm64_codegen->InvokeRuntime(entrypoint, instruction_, instruction_->GetDexPc(), this);
CheckEntrypointTypes<kQuickThrowStringBounds, void, int32_t, int32_t>();
CheckEntrypointTypes<kQuickThrowArrayBounds, void, int32_t, int32_t>();
}
bool IsFatal() const OVERRIDE { return true; }
const char* GetDescription() const OVERRIDE { return "BoundsCheckSlowPathARM64"; }
private:
DISALLOW_COPY_AND_ASSIGN(BoundsCheckSlowPathARM64);
};
class DivZeroCheckSlowPathARM64 : public SlowPathCodeARM64 {
public:
explicit DivZeroCheckSlowPathARM64(HDivZeroCheck* instruction) : SlowPathCodeARM64(instruction) {}
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
CodeGeneratorARM64* arm64_codegen = down_cast<CodeGeneratorARM64*>(codegen);
__ Bind(GetEntryLabel());
arm64_codegen->InvokeRuntime(kQuickThrowDivZero, instruction_, instruction_->GetDexPc(), this);
CheckEntrypointTypes<kQuickThrowDivZero, void, void>();
}
bool IsFatal() const OVERRIDE { return true; }
const char* GetDescription() const OVERRIDE { return "DivZeroCheckSlowPathARM64"; }
private:
DISALLOW_COPY_AND_ASSIGN(DivZeroCheckSlowPathARM64);
};
class LoadClassSlowPathARM64 : public SlowPathCodeARM64 {
public:
LoadClassSlowPathARM64(HLoadClass* cls,
HInstruction* at,
uint32_t dex_pc,
bool do_clinit)
: SlowPathCodeARM64(at),
cls_(cls),
dex_pc_(dex_pc),
do_clinit_(do_clinit) {
DCHECK(at->IsLoadClass() || at->IsClinitCheck());
}
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
LocationSummary* locations = instruction_->GetLocations();
Location out = locations->Out();
CodeGeneratorARM64* arm64_codegen = down_cast<CodeGeneratorARM64*>(codegen);
__ Bind(GetEntryLabel());
SaveLiveRegisters(codegen, locations);
InvokeRuntimeCallingConvention calling_convention;
dex::TypeIndex type_index = cls_->GetTypeIndex();
__ Mov(calling_convention.GetRegisterAt(0).W(), type_index.index_);
QuickEntrypointEnum entrypoint = do_clinit_ ? kQuickInitializeStaticStorage
: kQuickInitializeType;
arm64_codegen->InvokeRuntime(entrypoint, instruction_, dex_pc_, this);
if (do_clinit_) {
CheckEntrypointTypes<kQuickInitializeStaticStorage, void*, uint32_t>();
} else {
CheckEntrypointTypes<kQuickInitializeType, void*, uint32_t>();
}
// Move the class to the desired location.
if (out.IsValid()) {
DCHECK(out.IsRegister() && !locations->GetLiveRegisters()->ContainsCoreRegister(out.reg()));
DataType::Type type = instruction_->GetType();
arm64_codegen->MoveLocation(out, calling_convention.GetReturnLocation(type), type);
}
RestoreLiveRegisters(codegen, locations);
__ B(GetExitLabel());
}
const char* GetDescription() const OVERRIDE { return "LoadClassSlowPathARM64"; }
private:
// The class this slow path will load.
HLoadClass* const cls_;
// The dex PC of `at_`.
const uint32_t dex_pc_;
// Whether to initialize the class.
const bool do_clinit_;
DISALLOW_COPY_AND_ASSIGN(LoadClassSlowPathARM64);
};
class LoadStringSlowPathARM64 : public SlowPathCodeARM64 {
public:
explicit LoadStringSlowPathARM64(HLoadString* instruction)
: SlowPathCodeARM64(instruction) {}
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
LocationSummary* locations = instruction_->GetLocations();
DCHECK(!locations->GetLiveRegisters()->ContainsCoreRegister(locations->Out().reg()));
CodeGeneratorARM64* arm64_codegen = down_cast<CodeGeneratorARM64*>(codegen);
__ Bind(GetEntryLabel());
SaveLiveRegisters(codegen, locations);
InvokeRuntimeCallingConvention calling_convention;
const dex::StringIndex string_index = instruction_->AsLoadString()->GetStringIndex();
__ Mov(calling_convention.GetRegisterAt(0).W(), string_index.index_);
arm64_codegen->InvokeRuntime(kQuickResolveString, instruction_, instruction_->GetDexPc(), this);
CheckEntrypointTypes<kQuickResolveString, void*, uint32_t>();
DataType::Type type = instruction_->GetType();
arm64_codegen->MoveLocation(locations->Out(), calling_convention.GetReturnLocation(type), type);
RestoreLiveRegisters(codegen, locations);
__ B(GetExitLabel());
}
const char* GetDescription() const OVERRIDE { return "LoadStringSlowPathARM64"; }
private:
DISALLOW_COPY_AND_ASSIGN(LoadStringSlowPathARM64);
};
class NullCheckSlowPathARM64 : public SlowPathCodeARM64 {
public:
explicit NullCheckSlowPathARM64(HNullCheck* instr) : SlowPathCodeARM64(instr) {}
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
CodeGeneratorARM64* arm64_codegen = down_cast<CodeGeneratorARM64*>(codegen);
__ Bind(GetEntryLabel());
if (instruction_->CanThrowIntoCatchBlock()) {
// Live registers will be restored in the catch block if caught.
SaveLiveRegisters(codegen, instruction_->GetLocations());
}
arm64_codegen->InvokeRuntime(kQuickThrowNullPointer,
instruction_,
instruction_->GetDexPc(),
this);
CheckEntrypointTypes<kQuickThrowNullPointer, void, void>();
}
bool IsFatal() const OVERRIDE { return true; }
const char* GetDescription() const OVERRIDE { return "NullCheckSlowPathARM64"; }
private:
DISALLOW_COPY_AND_ASSIGN(NullCheckSlowPathARM64);
};
class SuspendCheckSlowPathARM64 : public SlowPathCodeARM64 {
public:
SuspendCheckSlowPathARM64(HSuspendCheck* instruction, HBasicBlock* successor)
: SlowPathCodeARM64(instruction), successor_(successor) {}
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
LocationSummary* locations = instruction_->GetLocations();
CodeGeneratorARM64* arm64_codegen = down_cast<CodeGeneratorARM64*>(codegen);
__ Bind(GetEntryLabel());
SaveLiveRegisters(codegen, locations); // Only saves live 128-bit regs for SIMD.
arm64_codegen->InvokeRuntime(kQuickTestSuspend, instruction_, instruction_->GetDexPc(), this);
CheckEntrypointTypes<kQuickTestSuspend, void, void>();
RestoreLiveRegisters(codegen, locations); // Only restores live 128-bit regs for SIMD.
if (successor_ == nullptr) {
__ B(GetReturnLabel());
} else {
__ B(arm64_codegen->GetLabelOf(successor_));
}
}
vixl::aarch64::Label* GetReturnLabel() {
DCHECK(successor_ == nullptr);
return &return_label_;
}
HBasicBlock* GetSuccessor() const {
return successor_;
}
const char* GetDescription() const OVERRIDE { return "SuspendCheckSlowPathARM64"; }
private:
// If not null, the block to branch to after the suspend check.
HBasicBlock* const successor_;
// If `successor_` is null, the label to branch to after the suspend check.
vixl::aarch64::Label return_label_;
DISALLOW_COPY_AND_ASSIGN(SuspendCheckSlowPathARM64);
};
class TypeCheckSlowPathARM64 : public SlowPathCodeARM64 {
public:
TypeCheckSlowPathARM64(HInstruction* instruction, bool is_fatal)
: SlowPathCodeARM64(instruction), is_fatal_(is_fatal) {}
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
LocationSummary* locations = instruction_->GetLocations();
DCHECK(instruction_->IsCheckCast()
|| !locations->GetLiveRegisters()->ContainsCoreRegister(locations->Out().reg()));
CodeGeneratorARM64* arm64_codegen = down_cast<CodeGeneratorARM64*>(codegen);
uint32_t dex_pc = instruction_->GetDexPc();
__ Bind(GetEntryLabel());
if (!is_fatal_ || instruction_->CanThrowIntoCatchBlock()) {
SaveLiveRegisters(codegen, locations);
}
// We're moving two locations to locations that could overlap, so we need a parallel
// move resolver.
InvokeRuntimeCallingConvention calling_convention;
codegen->EmitParallelMoves(locations->InAt(0),
LocationFrom(calling_convention.GetRegisterAt(0)),
DataType::Type::kReference,
locations->InAt(1),
LocationFrom(calling_convention.GetRegisterAt(1)),
DataType::Type::kReference);
if (instruction_->IsInstanceOf()) {
arm64_codegen->InvokeRuntime(kQuickInstanceofNonTrivial, instruction_, dex_pc, this);
CheckEntrypointTypes<kQuickInstanceofNonTrivial, size_t, mirror::Object*, mirror::Class*>();
DataType::Type ret_type = instruction_->GetType();
Location ret_loc = calling_convention.GetReturnLocation(ret_type);
arm64_codegen->MoveLocation(locations->Out(), ret_loc, ret_type);
} else {
DCHECK(instruction_->IsCheckCast());
arm64_codegen->InvokeRuntime(kQuickCheckInstanceOf, instruction_, dex_pc, this);
CheckEntrypointTypes<kQuickCheckInstanceOf, void, mirror::Object*, mirror::Class*>();
}
if (!is_fatal_) {
RestoreLiveRegisters(codegen, locations);
__ B(GetExitLabel());
}
}
const char* GetDescription() const OVERRIDE { return "TypeCheckSlowPathARM64"; }
bool IsFatal() const OVERRIDE { return is_fatal_; }
private:
const bool is_fatal_;
DISALLOW_COPY_AND_ASSIGN(TypeCheckSlowPathARM64);
};
class DeoptimizationSlowPathARM64 : public SlowPathCodeARM64 {
public:
explicit DeoptimizationSlowPathARM64(HDeoptimize* instruction)
: SlowPathCodeARM64(instruction) {}
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
CodeGeneratorARM64* arm64_codegen = down_cast<CodeGeneratorARM64*>(codegen);
__ Bind(GetEntryLabel());
LocationSummary* locations = instruction_->GetLocations();
SaveLiveRegisters(codegen, locations);
InvokeRuntimeCallingConvention calling_convention;
__ Mov(calling_convention.GetRegisterAt(0),
static_cast<uint32_t>(instruction_->AsDeoptimize()->GetDeoptimizationKind()));
arm64_codegen->InvokeRuntime(kQuickDeoptimize, instruction_, instruction_->GetDexPc(), this);
CheckEntrypointTypes<kQuickDeoptimize, void, DeoptimizationKind>();
}
const char* GetDescription() const OVERRIDE { return "DeoptimizationSlowPathARM64"; }
private:
DISALLOW_COPY_AND_ASSIGN(DeoptimizationSlowPathARM64);
};
class ArraySetSlowPathARM64 : public SlowPathCodeARM64 {
public:
explicit ArraySetSlowPathARM64(HInstruction* instruction) : SlowPathCodeARM64(instruction) {}
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
LocationSummary* locations = instruction_->GetLocations();
__ Bind(GetEntryLabel());
SaveLiveRegisters(codegen, locations);
InvokeRuntimeCallingConvention calling_convention;
HParallelMove parallel_move(codegen->GetGraph()->GetAllocator());
parallel_move.AddMove(
locations->InAt(0),
LocationFrom(calling_convention.GetRegisterAt(0)),
DataType::Type::kReference,
nullptr);
parallel_move.AddMove(
locations->InAt(1),
LocationFrom(calling_convention.GetRegisterAt(1)),
DataType::Type::kInt32,
nullptr);
parallel_move.AddMove(
locations->InAt(2),
LocationFrom(calling_convention.GetRegisterAt(2)),
DataType::Type::kReference,
nullptr);
codegen->GetMoveResolver()->EmitNativeCode(&parallel_move);
CodeGeneratorARM64* arm64_codegen = down_cast<CodeGeneratorARM64*>(codegen);
arm64_codegen->InvokeRuntime(kQuickAputObject, instruction_, instruction_->GetDexPc(), this);
CheckEntrypointTypes<kQuickAputObject, void, mirror::Array*, int32_t, mirror::Object*>();
RestoreLiveRegisters(codegen, locations);
__ B(GetExitLabel());
}
const char* GetDescription() const OVERRIDE { return "ArraySetSlowPathARM64"; }
private:
DISALLOW_COPY_AND_ASSIGN(ArraySetSlowPathARM64);
};
void JumpTableARM64::EmitTable(CodeGeneratorARM64* codegen) {
uint32_t num_entries = switch_instr_->GetNumEntries();
DCHECK_GE(num_entries, kPackedSwitchCompareJumpThreshold);
// We are about to use the assembler to place literals directly. Make sure we have enough
// underlying code buffer and we have generated the jump table with right size.
EmissionCheckScope scope(codegen->GetVIXLAssembler(),
num_entries * sizeof(int32_t),
CodeBufferCheckScope::kExactSize);
__ Bind(&table_start_);
const ArenaVector<HBasicBlock*>& successors = switch_instr_->GetBlock()->GetSuccessors();
for (uint32_t i = 0; i < num_entries; i++) {
vixl::aarch64::Label* target_label = codegen->GetLabelOf(successors[i]);
DCHECK(target_label->IsBound());
ptrdiff_t jump_offset = target_label->GetLocation() - table_start_.GetLocation();
DCHECK_GT(jump_offset, std::numeric_limits<int32_t>::min());
DCHECK_LE(jump_offset, std::numeric_limits<int32_t>::max());
Literal<int32_t> literal(jump_offset);
__ place(&literal);
}
}
// Abstract base class for read barrier slow paths marking a reference
// `ref`.
//
// Argument `entrypoint` must be a register location holding the read
// barrier marking runtime entry point to be invoked or an empty
// location; in the latter case, the read barrier marking runtime
// entry point will be loaded by the slow path code itself.
class ReadBarrierMarkSlowPathBaseARM64 : public SlowPathCodeARM64 {
protected:
ReadBarrierMarkSlowPathBaseARM64(HInstruction* instruction, Location ref, Location entrypoint)
: SlowPathCodeARM64(instruction), ref_(ref), entrypoint_(entrypoint) {
DCHECK(kEmitCompilerReadBarrier);
}
const char* GetDescription() const OVERRIDE { return "ReadBarrierMarkSlowPathBaseARM64"; }
// Generate assembly code calling the read barrier marking runtime
// entry point (ReadBarrierMarkRegX).
void GenerateReadBarrierMarkRuntimeCall(CodeGenerator* codegen) {
// No need to save live registers; it's taken care of by the
// entrypoint. Also, there is no need to update the stack mask,
// as this runtime call will not trigger a garbage collection.
CodeGeneratorARM64* arm64_codegen = down_cast<CodeGeneratorARM64*>(codegen);
DCHECK_NE(ref_.reg(), LR);
DCHECK_NE(ref_.reg(), WSP);
DCHECK_NE(ref_.reg(), WZR);
// IP0 is used internally by the ReadBarrierMarkRegX entry point
// as a temporary, it cannot be the entry point's input/output.
DCHECK_NE(ref_.reg(), IP0);
DCHECK(0 <= ref_.reg() && ref_.reg() < kNumberOfWRegisters) << ref_.reg();
// "Compact" slow path, saving two moves.
//
// Instead of using the standard runtime calling convention (input
// and output in W0):
//
// W0 <- ref
// W0 <- ReadBarrierMark(W0)
// ref <- W0
//
// we just use rX (the register containing `ref`) as input and output
// of a dedicated entrypoint:
//
// rX <- ReadBarrierMarkRegX(rX)
//
if (entrypoint_.IsValid()) {
arm64_codegen->ValidateInvokeRuntimeWithoutRecordingPcInfo(instruction_, this);
__ Blr(XRegisterFrom(entrypoint_));
} else {
// Entrypoint is not already loaded, load from the thread.
int32_t entry_point_offset =
Thread::ReadBarrierMarkEntryPointsOffset<kArm64PointerSize>(ref_.reg());
// This runtime call does not require a stack map.
arm64_codegen->InvokeRuntimeWithoutRecordingPcInfo(entry_point_offset, instruction_, this);
}
}
// The location (register) of the marked object reference.
const Location ref_;
// The location of the entrypoint if it is already loaded.
const Location entrypoint_;
private:
DISALLOW_COPY_AND_ASSIGN(ReadBarrierMarkSlowPathBaseARM64);
};
// Slow path marking an object reference `ref` during a read
// barrier. The field `obj.field` in the object `obj` holding this
// reference does not get updated by this slow path after marking.
//
// This means that after the execution of this slow path, `ref` will
// always be up-to-date, but `obj.field` may not; i.e., after the
// flip, `ref` will be a to-space reference, but `obj.field` will
// probably still be a from-space reference (unless it gets updated by
// another thread, or if another thread installed another object
// reference (different from `ref`) in `obj.field`).
//
// Argument `entrypoint` must be a register location holding the read
// barrier marking runtime entry point to be invoked or an empty
// location; in the latter case, the read barrier marking runtime
// entry point will be loaded by the slow path code itself.
class ReadBarrierMarkSlowPathARM64 : public ReadBarrierMarkSlowPathBaseARM64 {
public:
ReadBarrierMarkSlowPathARM64(HInstruction* instruction,
Location ref,
Location entrypoint = Location::NoLocation())
: ReadBarrierMarkSlowPathBaseARM64(instruction, ref, entrypoint) {
DCHECK(kEmitCompilerReadBarrier);
}
const char* GetDescription() const OVERRIDE { return "ReadBarrierMarkSlowPathARM64"; }
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
LocationSummary* locations = instruction_->GetLocations();
DCHECK(locations->CanCall());
DCHECK(ref_.IsRegister()) << ref_;
DCHECK(!locations->GetLiveRegisters()->ContainsCoreRegister(ref_.reg())) << ref_.reg();
DCHECK(instruction_->IsLoadClass() || instruction_->IsLoadString())
<< "Unexpected instruction in read barrier marking slow path: "
<< instruction_->DebugName();
__ Bind(GetEntryLabel());
GenerateReadBarrierMarkRuntimeCall(codegen);
__ B(GetExitLabel());
}
private:
DISALLOW_COPY_AND_ASSIGN(ReadBarrierMarkSlowPathARM64);
};
// Slow path loading `obj`'s lock word, loading a reference from
// object `*(obj + offset + (index << scale_factor))` into `ref`, and
// marking `ref` if `obj` is gray according to the lock word (Baker
// read barrier). The field `obj.field` in the object `obj` holding
// this reference does not get updated by this slow path after marking
// (see LoadReferenceWithBakerReadBarrierAndUpdateFieldSlowPathARM64
// below for that).
//
// This means that after the execution of this slow path, `ref` will
// always be up-to-date, but `obj.field` may not; i.e., after the
// flip, `ref` will be a to-space reference, but `obj.field` will
// probably still be a from-space reference (unless it gets updated by
// another thread, or if another thread installed another object
// reference (different from `ref`) in `obj.field`).
//
// Argument `entrypoint` must be a register location holding the read
// barrier marking runtime entry point to be invoked or an empty
// location; in the latter case, the read barrier marking runtime
// entry point will be loaded by the slow path code itself.
class LoadReferenceWithBakerReadBarrierSlowPathARM64 : public ReadBarrierMarkSlowPathBaseARM64 {
public:
LoadReferenceWithBakerReadBarrierSlowPathARM64(HInstruction* instruction,
Location ref,
Register obj,
uint32_t offset,
Location index,
size_t scale_factor,
bool needs_null_check,
bool use_load_acquire,
Register temp,
Location entrypoint = Location::NoLocation())
: ReadBarrierMarkSlowPathBaseARM64(instruction, ref, entrypoint),
obj_(obj),
offset_(offset),
index_(index),
scale_factor_(scale_factor),
needs_null_check_(needs_null_check),
use_load_acquire_(use_load_acquire),
temp_(temp) {
DCHECK(kEmitCompilerReadBarrier);
DCHECK(kUseBakerReadBarrier);
}
const char* GetDescription() const OVERRIDE {
return "LoadReferenceWithBakerReadBarrierSlowPathARM64";
}
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
LocationSummary* locations = instruction_->GetLocations();
DCHECK(locations->CanCall());
DCHECK(ref_.IsRegister()) << ref_;
DCHECK(!locations->GetLiveRegisters()->ContainsCoreRegister(ref_.reg())) << ref_.reg();
DCHECK(obj_.IsW());
DCHECK_NE(ref_.reg(), LocationFrom(temp_).reg());
DCHECK(instruction_->IsInstanceFieldGet() ||
instruction_->IsStaticFieldGet() ||
instruction_->IsArrayGet() ||
instruction_->IsArraySet() ||
instruction_->IsInstanceOf() ||
instruction_->IsCheckCast() ||
(instruction_->IsInvokeVirtual() && instruction_->GetLocations()->Intrinsified()) ||
(instruction_->IsInvokeStaticOrDirect() && instruction_->GetLocations()->Intrinsified()))
<< "Unexpected instruction in read barrier marking slow path: "
<< instruction_->DebugName();
// The read barrier instrumentation of object ArrayGet
// instructions does not support the HIntermediateAddress
// instruction.
DCHECK(!(instruction_->IsArrayGet() &&
instruction_->AsArrayGet()->GetArray()->IsIntermediateAddress()));
// Temporary register `temp_`, used to store the lock word, must
// not be IP0 nor IP1, as we may use them to emit the reference
// load (in the call to GenerateRawReferenceLoad below), and we
// need the lock word to still be in `temp_` after the reference
// load.
DCHECK_NE(LocationFrom(temp_).reg(), IP0);
DCHECK_NE(LocationFrom(temp_).reg(), IP1);
__ Bind(GetEntryLabel());
// When using MaybeGenerateReadBarrierSlow, the read barrier call is
// inserted after the original load. However, in fast path based
// Baker's read barriers, we need to perform the load of
// mirror::Object::monitor_ *before* the original reference load.
// This load-load ordering is required by the read barrier.
// The slow path (for Baker's algorithm) should look like:
//
// uint32_t rb_state = Lockword(obj->monitor_).ReadBarrierState();
// lfence; // Load fence or artificial data dependency to prevent load-load reordering
// HeapReference<mirror::Object> ref = *src; // Original reference load.
// bool is_gray = (rb_state == ReadBarrier::GrayState());
// if (is_gray) {
// ref = entrypoint(ref); // ref = ReadBarrier::Mark(ref); // Runtime entry point call.
// }
//
// Note: the original implementation in ReadBarrier::Barrier is
// slightly more complex as it performs additional checks that we do
// not do here for performance reasons.
// /* int32_t */ monitor = obj->monitor_
uint32_t monitor_offset = mirror::Object::MonitorOffset().Int32Value();
__ Ldr(temp_, HeapOperand(obj_, monitor_offset));
if (needs_null_check_) {
codegen->MaybeRecordImplicitNullCheck(instruction_);
}
// /* LockWord */ lock_word = LockWord(monitor)
static_assert(sizeof(LockWord) == sizeof(int32_t),
"art::LockWord and int32_t have different sizes.");
// Introduce a dependency on the lock_word including rb_state,
// to prevent load-load reordering, and without using
// a memory barrier (which would be more expensive).
// `obj` is unchanged by this operation, but its value now depends
// on `temp`.
__ Add(obj_.X(), obj_.X(), Operand(temp_.X(), LSR, 32));
// The actual reference load.
// A possible implicit null check has already been handled above.
CodeGeneratorARM64* arm64_codegen = down_cast<CodeGeneratorARM64*>(codegen);
arm64_codegen->GenerateRawReferenceLoad(instruction_,
ref_,
obj_,
offset_,
index_,
scale_factor_,
/* needs_null_check */ false,
use_load_acquire_);
// Mark the object `ref` when `obj` is gray.
//
// if (rb_state == ReadBarrier::GrayState())
// ref = ReadBarrier::Mark(ref);
//
// Given the numeric representation, it's enough to check the low bit of the rb_state.
static_assert(ReadBarrier::WhiteState() == 0, "Expecting white to have value 0");
static_assert(ReadBarrier::GrayState() == 1, "Expecting gray to have value 1");
__ Tbz(temp_, LockWord::kReadBarrierStateShift, GetExitLabel());
GenerateReadBarrierMarkRuntimeCall(codegen);
__ B(GetExitLabel());
}
private:
// The register containing the object holding the marked object reference field.
Register obj_;
// The offset, index and scale factor to access the reference in `obj_`.
uint32_t offset_;
Location index_;
size_t scale_factor_;
// Is a null check required?
bool needs_null_check_;
// Should this reference load use Load-Acquire semantics?
bool use_load_acquire_;
// A temporary register used to hold the lock word of `obj_`.
Register temp_;
DISALLOW_COPY_AND_ASSIGN(LoadReferenceWithBakerReadBarrierSlowPathARM64);
};
// Slow path loading `obj`'s lock word, loading a reference from
// object `*(obj + offset + (index << scale_factor))` into `ref`, and
// marking `ref` if `obj` is gray according to the lock word (Baker
// read barrier). If needed, this slow path also atomically updates
// the field `obj.field` in the object `obj` holding this reference
// after marking (contrary to
// LoadReferenceWithBakerReadBarrierSlowPathARM64 above, which never
// tries to update `obj.field`).
//
// This means that after the execution of this slow path, both `ref`
// and `obj.field` will be up-to-date; i.e., after the flip, both will
// hold the same to-space reference (unless another thread installed
// another object reference (different from `ref`) in `obj.field`).
//
// Argument `entrypoint` must be a register location holding the read
// barrier marking runtime entry point to be invoked or an empty
// location; in the latter case, the read barrier marking runtime
// entry point will be loaded by the slow path code itself.
class LoadReferenceWithBakerReadBarrierAndUpdateFieldSlowPathARM64
: public ReadBarrierMarkSlowPathBaseARM64 {
public:
LoadReferenceWithBakerReadBarrierAndUpdateFieldSlowPathARM64(
HInstruction* instruction,
Location ref,
Register obj,
uint32_t offset,
Location index,
size_t scale_factor,
bool needs_null_check,
bool use_load_acquire,
Register temp,
Location entrypoint = Location::NoLocation())
: ReadBarrierMarkSlowPathBaseARM64(instruction, ref, entrypoint),
obj_(obj),
offset_(offset),
index_(index),
scale_factor_(scale_factor),
needs_null_check_(needs_null_check),
use_load_acquire_(use_load_acquire),
temp_(temp) {
DCHECK(kEmitCompilerReadBarrier);
DCHECK(kUseBakerReadBarrier);
}
const char* GetDescription() const OVERRIDE {
return "LoadReferenceWithBakerReadBarrierAndUpdateFieldSlowPathARM64";
}
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
LocationSummary* locations = instruction_->GetLocations();
Register ref_reg = WRegisterFrom(ref_);
DCHECK(locations->CanCall());
DCHECK(ref_.IsRegister()) << ref_;
DCHECK(!locations->GetLiveRegisters()->ContainsCoreRegister(ref_.reg())) << ref_.reg();
DCHECK(obj_.IsW());
DCHECK_NE(ref_.reg(), LocationFrom(temp_).reg());
// This slow path is only used by the UnsafeCASObject intrinsic at the moment.
DCHECK((instruction_->IsInvokeVirtual() && instruction_->GetLocations()->Intrinsified()))
<< "Unexpected instruction in read barrier marking and field updating slow path: "
<< instruction_->DebugName();
DCHECK(instruction_->GetLocations()->Intrinsified());
DCHECK_EQ(instruction_->AsInvoke()->GetIntrinsic(), Intrinsics::kUnsafeCASObject);
DCHECK_EQ(offset_, 0u);
DCHECK_EQ(scale_factor_, 0u);
DCHECK_EQ(use_load_acquire_, false);
// The location of the offset of the marked reference field within `obj_`.
Location field_offset = index_;
DCHECK(field_offset.IsRegister()) << field_offset;
// Temporary register `temp_`, used to store the lock word, must
// not be IP0 nor IP1, as we may use them to emit the reference
// load (in the call to GenerateRawReferenceLoad below), and we
// need the lock word to still be in `temp_` after the reference
// load.
DCHECK_NE(LocationFrom(temp_).reg(), IP0);
DCHECK_NE(LocationFrom(temp_).reg(), IP1);
__ Bind(GetEntryLabel());
// The implementation is similar to LoadReferenceWithBakerReadBarrierSlowPathARM64's:
//
// uint32_t rb_state = Lockword(obj->monitor_).ReadBarrierState();
// lfence; // Load fence or artificial data dependency to prevent load-load reordering
// HeapReference<mirror::Object> ref = *src; // Original reference load.
// bool is_gray = (rb_state == ReadBarrier::GrayState());
// if (is_gray) {
// old_ref = ref;
// ref = entrypoint(ref); // ref = ReadBarrier::Mark(ref); // Runtime entry point call.
// compareAndSwapObject(obj, field_offset, old_ref, ref);
// }
// /* int32_t */ monitor = obj->monitor_
uint32_t monitor_offset = mirror::Object::MonitorOffset().Int32Value();
__ Ldr(temp_, HeapOperand(obj_, monitor_offset));
if (needs_null_check_) {
codegen->MaybeRecordImplicitNullCheck(instruction_);
}
// /* LockWord */ lock_word = LockWord(monitor)
static_assert(sizeof(LockWord) == sizeof(int32_t),
"art::LockWord and int32_t have different sizes.");
// Introduce a dependency on the lock_word including rb_state,
// to prevent load-load reordering, and without using
// a memory barrier (which would be more expensive).
// `obj` is unchanged by this operation, but its value now depends
// on `temp`.
__ Add(obj_.X(), obj_.X(), Operand(temp_.X(), LSR, 32));
// The actual reference load.
// A possible implicit null check has already been handled above.
CodeGeneratorARM64* arm64_codegen = down_cast<CodeGeneratorARM64*>(codegen);
arm64_codegen->GenerateRawReferenceLoad(instruction_,
ref_,
obj_,
offset_,
index_,
scale_factor_,
/* needs_null_check */ false,
use_load_acquire_);
// Mark the object `ref` when `obj` is gray.
//
// if (rb_state == ReadBarrier::GrayState())
// ref = ReadBarrier::Mark(ref);
//
// Given the numeric representation, it's enough to check the low bit of the rb_state.
static_assert(ReadBarrier::WhiteState() == 0, "Expecting white to have value 0");
static_assert(ReadBarrier::GrayState() == 1, "Expecting gray to have value 1");
__ Tbz(temp_, LockWord::kReadBarrierStateShift, GetExitLabel());
// Save the old value of the reference before marking it.
// Note that we cannot use IP to save the old reference, as IP is
// used internally by the ReadBarrierMarkRegX entry point, and we
// need the old reference after the call to that entry point.
DCHECK_NE(LocationFrom(temp_).reg(), IP0);
__ Mov(temp_.W(), ref_reg);
GenerateReadBarrierMarkRuntimeCall(codegen);
// If the new reference is different from the old reference,
// update the field in the holder (`*(obj_ + field_offset)`).
//
// Note that this field could also hold a different object, if
// another thread had concurrently changed it. In that case, the
// LDXR/CMP/BNE sequence of instructions in the compare-and-set
// (CAS) operation below would abort the CAS, leaving the field
// as-is.
__ Cmp(temp_.W(), ref_reg);
__ B(eq, GetExitLabel());
// Update the the holder's field atomically. This may fail if
// mutator updates before us, but it's OK. This is achieved
// using a strong compare-and-set (CAS) operation with relaxed
// memory synchronization ordering, where the expected value is
// the old reference and the desired value is the new reference.
MacroAssembler* masm = arm64_codegen->GetVIXLAssembler();
UseScratchRegisterScope temps(masm);
// Convenience aliases.
Register base = obj_.W();
Register offset = XRegisterFrom(field_offset);
Register expected = temp_.W();
Register value = ref_reg;
Register tmp_ptr = temps.AcquireX(); // Pointer to actual memory.
Register tmp_value = temps.AcquireW(); // Value in memory.
__ Add(tmp_ptr, base.X(), Operand(offset));
if (kPoisonHeapReferences) {
arm64_codegen->GetAssembler()->PoisonHeapReference(expected);
if (value.Is(expected)) {
// Do not poison `value`, as it is the same register as
// `expected`, which has just been poisoned.
} else {
arm64_codegen->GetAssembler()->PoisonHeapReference(value);
}
}
// do {
// tmp_value = [tmp_ptr] - expected;
// } while (tmp_value == 0 && failure([tmp_ptr] <- r_new_value));
vixl::aarch64::Label loop_head, comparison_failed, exit_loop;
__ Bind(&loop_head);
__ Ldxr(tmp_value, MemOperand(tmp_ptr));
__ Cmp(tmp_value, expected);
__ B(&comparison_failed, ne);
__ Stxr(tmp_value, value, MemOperand(tmp_ptr));
__ Cbnz(tmp_value, &loop_head);
__ B(&exit_loop);
__ Bind(&comparison_failed);
__ Clrex();
__ Bind(&exit_loop);
if (kPoisonHeapReferences) {
arm64_codegen->GetAssembler()->UnpoisonHeapReference(expected);
if (value.Is(expected)) {
// Do not unpoison `value`, as it is the same register as
// `expected`, which has just been unpoisoned.
} else {
arm64_codegen->GetAssembler()->UnpoisonHeapReference(value);
}
}
__ B(GetExitLabel());
}
private:
// The register containing the object holding the marked object reference field.
const Register obj_;
// The offset, index and scale factor to access the reference in `obj_`.
uint32_t offset_;
Location index_;
size_t scale_factor_;
// Is a null check required?
bool needs_null_check_;
// Should this reference load use Load-Acquire semantics?
bool use_load_acquire_;
// A temporary register used to hold the lock word of `obj_`; and
// also to hold the original reference value, when the reference is
// marked.
const Register temp_;
DISALLOW_COPY_AND_ASSIGN(LoadReferenceWithBakerReadBarrierAndUpdateFieldSlowPathARM64);
};
// Slow path generating a read barrier for a heap reference.
class ReadBarrierForHeapReferenceSlowPathARM64 : public SlowPathCodeARM64 {
public:
ReadBarrierForHeapReferenceSlowPathARM64(HInstruction* instruction,
Location out,
Location ref,
Location obj,
uint32_t offset,
Location index)
: SlowPathCodeARM64(instruction),
out_(out),
ref_(ref),
obj_(obj),
offset_(offset),
index_(index) {
DCHECK(kEmitCompilerReadBarrier);
// If `obj` is equal to `out` or `ref`, it means the initial object
// has been overwritten by (or after) the heap object reference load
// to be instrumented, e.g.:
//
// __ Ldr(out, HeapOperand(out, class_offset);
// codegen_->GenerateReadBarrierSlow(instruction, out_loc, out_loc, out_loc, offset);
//
// In that case, we have lost the information about the original
// object, and the emitted read barrier cannot work properly.
DCHECK(!obj.Equals(out)) << "obj=" << obj << " out=" << out;
DCHECK(!obj.Equals(ref)) << "obj=" << obj << " ref=" << ref;
}
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
CodeGeneratorARM64* arm64_codegen = down_cast<CodeGeneratorARM64*>(codegen);
LocationSummary* locations = instruction_->GetLocations();
DataType::Type type = DataType::Type::kReference;
DCHECK(locations->CanCall());
DCHECK(!locations->GetLiveRegisters()->ContainsCoreRegister(out_.reg()));
DCHECK(instruction_->IsInstanceFieldGet() ||
instruction_->IsStaticFieldGet() ||
instruction_->IsArrayGet() ||
instruction_->IsInstanceOf() ||
instruction_->IsCheckCast() ||
(instruction_->IsInvokeVirtual() && instruction_->GetLocations()->Intrinsified()))
<< "Unexpected instruction in read barrier for heap reference slow path: "
<< instruction_->DebugName();
// The read barrier instrumentation of object ArrayGet
// instructions does not support the HIntermediateAddress
// instruction.
DCHECK(!(instruction_->IsArrayGet() &&
instruction_->AsArrayGet()->GetArray()->IsIntermediateAddress()));
__ Bind(GetEntryLabel());
SaveLiveRegisters(codegen, locations);
// We may have to change the index's value, but as `index_` is a
// constant member (like other "inputs" of this slow path),
// introduce a copy of it, `index`.
Location index = index_;
if (index_.IsValid()) {
// Handle `index_` for HArrayGet and UnsafeGetObject/UnsafeGetObjectVolatile intrinsics.
if (instruction_->IsArrayGet()) {
// Compute the actual memory offset and store it in `index`.
Register index_reg = RegisterFrom(index_, DataType::Type::kInt32);
DCHECK(locations->GetLiveRegisters()->ContainsCoreRegister(index_.reg()));
if (codegen->IsCoreCalleeSaveRegister(index_.reg())) {
// We are about to change the value of `index_reg` (see the
// calls to vixl::MacroAssembler::Lsl and
// vixl::MacroAssembler::Mov below), but it has
// not been saved by the previous call to
// art::SlowPathCode::SaveLiveRegisters, as it is a
// callee-save register --
// art::SlowPathCode::SaveLiveRegisters does not consider
// callee-save registers, as it has been designed with the
// assumption that callee-save registers are supposed to be
// handled by the called function. So, as a callee-save
// register, `index_reg` _would_ eventually be saved onto
// the stack, but it would be too late: we would have
// changed its value earlier. Therefore, we manually save
// it here into another freely available register,
// `free_reg`, chosen of course among the caller-save
// registers (as a callee-save `free_reg` register would
// exhibit the same problem).
//
// Note we could have requested a temporary register from
// the register allocator instead; but we prefer not to, as
// this is a slow path, and we know we can find a
// caller-save register that is available.
Register free_reg = FindAvailableCallerSaveRegister(codegen);
__ Mov(free_reg.W(), index_reg);
index_reg = free_reg;
index = LocationFrom(index_reg);
} else {
// The initial register stored in `index_` has already been
// saved in the call to art::SlowPathCode::SaveLiveRegisters
// (as it is not a callee-save register), so we can freely
// use it.
}
// Shifting the index value contained in `index_reg` by the scale
// factor (2) cannot overflow in practice, as the runtime is
// unable to allocate object arrays with a size larger than
// 2^26 - 1 (that is, 2^28 - 4 bytes).
__ Lsl(index_reg, index_reg, DataType::SizeShift(type));
static_assert(
sizeof(mirror::HeapReference<mirror::Object>) == sizeof(int32_t),
"art::mirror::HeapReference<art::mirror::Object> and int32_t have different sizes.");
__ Add(index_reg, index_reg, Operand(offset_));
} else {
// In the case of the UnsafeGetObject/UnsafeGetObjectVolatile
// intrinsics, `index_` is not shifted by a scale factor of 2
// (as in the case of ArrayGet), as it is actually an offset
// to an object field within an object.
DCHECK(instruction_->IsInvoke()) << instruction_->DebugName();
DCHECK(instruction_->GetLocations()->Intrinsified());
DCHECK((instruction_->AsInvoke()->GetIntrinsic() == Intrinsics::kUnsafeGetObject) ||
(instruction_->AsInvoke()->GetIntrinsic() == Intrinsics::kUnsafeGetObjectVolatile))
<< instruction_->AsInvoke()->GetIntrinsic();
DCHECK_EQ(offset_, 0u);
DCHECK(index_.IsRegister());
}
}
// We're moving two or three locations to locations that could
// overlap, so we need a parallel move resolver.
InvokeRuntimeCallingConvention calling_convention;
HParallelMove parallel_move(codegen->GetGraph()->GetAllocator());
parallel_move.AddMove(ref_,
LocationFrom(calling_convention.GetRegisterAt(0)),
type,
nullptr);
parallel_move.AddMove(obj_,
LocationFrom(calling_convention.GetRegisterAt(1)),
type,
nullptr);
if (index.IsValid()) {
parallel_move.AddMove(index,
LocationFrom(calling_convention.GetRegisterAt(2)),
DataType::Type::kInt32,
nullptr);
codegen->GetMoveResolver()->EmitNativeCode(&parallel_move);
} else {
codegen->GetMoveResolver()->EmitNativeCode(&parallel_move);
arm64_codegen->MoveConstant(LocationFrom(calling_convention.GetRegisterAt(2)), offset_);
}
arm64_codegen->InvokeRuntime(kQuickReadBarrierSlow,
instruction_,
instruction_->GetDexPc(),
this);
CheckEntrypointTypes<
kQuickReadBarrierSlow, mirror::Object*, mirror::Object*, mirror::Object*, uint32_t>();
arm64_codegen->MoveLocation(out_, calling_convention.GetReturnLocation(type), type);
RestoreLiveRegisters(codegen, locations);
__ B(GetExitLabel());
}
const char* GetDescription() const OVERRIDE { return "ReadBarrierForHeapReferenceSlowPathARM64"; }
private:
Register FindAvailableCallerSaveRegister(CodeGenerator* codegen) {
size_t ref = static_cast<int>(XRegisterFrom(ref_).GetCode());
size_t obj = static_cast<int>(XRegisterFrom(obj_).GetCode());
for (size_t i = 0, e = codegen->GetNumberOfCoreRegisters(); i < e; ++i) {
if (i != ref && i != obj && !codegen->IsCoreCalleeSaveRegister(i)) {
return Register(VIXLRegCodeFromART(i), kXRegSize);
}
}
// We shall never fail to find a free caller-save register, as
// there are more than two core caller-save registers on ARM64
// (meaning it is possible to find one which is different from
// `ref` and `obj`).
DCHECK_GT(codegen->GetNumberOfCoreCallerSaveRegisters(), 2u);
LOG(FATAL) << "Could not find a free register";
UNREACHABLE();
}
const Location out_;
const Location ref_;
const Location obj_;
const uint32_t offset_;
// An additional location containing an index to an array.
// Only used for HArrayGet and the UnsafeGetObject &
// UnsafeGetObjectVolatile intrinsics.
const Location index_;
DISALLOW_COPY_AND_ASSIGN(ReadBarrierForHeapReferenceSlowPathARM64);
};
// Slow path generating a read barrier for a GC root.
class ReadBarrierForRootSlowPathARM64 : public SlowPathCodeARM64 {
public:
ReadBarrierForRootSlowPathARM64(HInstruction* instruction, Location out, Location root)
: SlowPathCodeARM64(instruction), out_(out), root_(root) {
DCHECK(kEmitCompilerReadBarrier);
}
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
LocationSummary* locations = instruction_->GetLocations();
DataType::Type type = DataType::Type::kReference;
DCHECK(locations->CanCall());
DCHECK(!locations->GetLiveRegisters()->ContainsCoreRegister(out_.reg()));
DCHECK(instruction_->IsLoadClass() || instruction_->IsLoadString())
<< "Unexpected instruction in read barrier for GC root slow path: "
<< instruction_->DebugName();
__ Bind(GetEntryLabel());
SaveLiveRegisters(codegen, locations);
InvokeRuntimeCallingConvention calling_convention;
CodeGeneratorARM64* arm64_codegen = down_cast<CodeGeneratorARM64*>(codegen);
// The argument of the ReadBarrierForRootSlow is not a managed
// reference (`mirror::Object*`), but a `GcRoot<mirror::Object>*`;
// thus we need a 64-bit move here, and we cannot use
//
// arm64_codegen->MoveLocation(
// LocationFrom(calling_convention.GetRegisterAt(0)),
// root_,
// type);
//
// which would emit a 32-bit move, as `type` is a (32-bit wide)
// reference type (`DataType::Type::kReference`).
__ Mov(calling_convention.GetRegisterAt(0), XRegisterFrom(out_));
arm64_codegen->InvokeRuntime(kQuickReadBarrierForRootSlow,
instruction_,
instruction_->GetDexPc(),
this);
CheckEntrypointTypes<kQuickReadBarrierForRootSlow, mirror::Object*, GcRoot<mirror::Object>*>();
arm64_codegen->MoveLocation(out_, calling_convention.GetReturnLocation(type), type);
RestoreLiveRegisters(codegen, locations);
__ B(GetExitLabel());
}
const char* GetDescription() const OVERRIDE { return "ReadBarrierForRootSlowPathARM64"; }
private:
const Location out_;
const Location root_;
DISALLOW_COPY_AND_ASSIGN(ReadBarrierForRootSlowPathARM64);
};
#undef __
Location InvokeDexCallingConventionVisitorARM64::GetNextLocation(DataType::Type type) {
Location next_location;
if (type == DataType::Type::kVoid) {
LOG(FATAL) << "Unreachable type " << type;
}
if (DataType::IsFloatingPointType(type) &&
(float_index_ < calling_convention.GetNumberOfFpuRegisters())) {
next_location = LocationFrom(calling_convention.GetFpuRegisterAt(float_index_++));
} else if (!DataType::IsFloatingPointType(type) &&
(gp_index_ < calling_convention.GetNumberOfRegisters())) {
next_location = LocationFrom(calling_convention.GetRegisterAt(gp_index_++));
} else {
size_t stack_offset = calling_convention.GetStackOffsetOf(stack_index_);
next_location = DataType::Is64BitType(type) ? Location::DoubleStackSlot(stack_offset)
: Location::StackSlot(stack_offset);
}
// Space on the stack is reserved for all arguments.
stack_index_ += DataType::Is64BitType(type) ? 2 : 1;
return next_location;
}
Location InvokeDexCallingConventionVisitorARM64::GetMethodLocation() const {
return LocationFrom(kArtMethodRegister);
}
CodeGeneratorARM64::CodeGeneratorARM64(HGraph* graph,
const Arm64InstructionSetFeatures& isa_features,
const CompilerOptions& compiler_options,
OptimizingCompilerStats* stats)
: CodeGenerator(graph,
kNumberOfAllocatableRegisters,
kNumberOfAllocatableFPRegisters,
kNumberOfAllocatableRegisterPairs,
callee_saved_core_registers.GetList(),
callee_saved_fp_registers.GetList(),
compiler_options,
stats),
block_labels_(graph->GetAllocator()->Adapter(kArenaAllocCodeGenerator)),
jump_tables_(graph->GetAllocator()->Adapter(kArenaAllocCodeGenerator)),
location_builder_(graph, this),
instruction_visitor_(graph, this),
move_resolver_(graph->GetAllocator(), this),
assembler_(graph->GetAllocator()),
isa_features_(isa_features),
uint32_literals_(std::less<uint32_t>(),
graph->GetAllocator()->Adapter(kArenaAllocCodeGenerator)),
uint64_literals_(std::less<uint64_t>(),
graph->GetAllocator()->Adapter(kArenaAllocCodeGenerator)),
boot_image_method_patches_(graph->GetAllocator()->Adapter(kArenaAllocCodeGenerator)),
method_bss_entry_patches_(graph->GetAllocator()->Adapter(kArenaAllocCodeGenerator)),
boot_image_type_patches_(graph->GetAllocator()->Adapter(kArenaAllocCodeGenerator)),
type_bss_entry_patches_(graph->GetAllocator()->Adapter(kArenaAllocCodeGenerator)),
boot_image_string_patches_(graph->GetAllocator()->Adapter(kArenaAllocCodeGenerator)),
string_bss_entry_patches_(graph->GetAllocator()->Adapter(kArenaAllocCodeGenerator)),
baker_read_barrier_patches_(graph->GetAllocator()->Adapter(kArenaAllocCodeGenerator)),
jit_string_patches_(StringReferenceValueComparator(),
graph->GetAllocator()->Adapter(kArenaAllocCodeGenerator)),
jit_class_patches_(TypeReferenceValueComparator(),
graph->GetAllocator()->Adapter(kArenaAllocCodeGenerator)) {
// Save the link register (containing the return address) to mimic Quick.
AddAllocatedRegister(LocationFrom(lr));
}
#define __ GetVIXLAssembler()->
void CodeGeneratorARM64::EmitJumpTables() {
for (auto&& jump_table : jump_tables_) {
jump_table->EmitTable(this);
}
}
void CodeGeneratorARM64::Finalize(CodeAllocator* allocator) {
EmitJumpTables();
// Ensure we emit the literal pool.
__ FinalizeCode();
CodeGenerator::Finalize(allocator);
// Verify Baker read barrier linker patches.
if (kIsDebugBuild) {
ArrayRef<const uint8_t> code = allocator->GetMemory();
for (const BakerReadBarrierPatchInfo& info : baker_read_barrier_patches_) {
DCHECK(info.label.IsBound());
uint32_t literal_offset = info.label.GetLocation();
DCHECK_ALIGNED(literal_offset, 4u);
auto GetInsn = [&code](uint32_t offset) {
DCHECK_ALIGNED(offset, 4u);
return
(static_cast<uint32_t>(code[offset + 0]) << 0) +
(static_cast<uint32_t>(code[offset + 1]) << 8) +
(static_cast<uint32_t>(code[offset + 2]) << 16)+
(static_cast<uint32_t>(code[offset + 3]) << 24);
};
const uint32_t encoded_data = info.custom_data;
BakerReadBarrierKind kind = BakerReadBarrierKindField::Decode(encoded_data);
// Check that the next instruction matches the expected LDR.
switch (kind) {
case BakerReadBarrierKind::kField: {
DCHECK_GE(code.size() - literal_offset, 8u);
uint32_t next_insn = GetInsn(literal_offset + 4u);
// LDR (immediate) with correct base_reg.
CheckValidReg(next_insn & 0x1fu); // Check destination register.
const uint32_t base_reg = BakerReadBarrierFirstRegField::Decode(encoded_data);
CHECK_EQ(next_insn & 0xffc003e0u, 0xb9400000u | (base_reg << 5));
break;
}
case BakerReadBarrierKind::kArray: {
DCHECK_GE(code.size() - literal_offset, 8u);
uint32_t next_insn = GetInsn(literal_offset + 4u);
// LDR (register) with the correct base_reg, size=10 (32-bit), option=011 (extend = LSL),
// and S=1 (shift amount = 2 for 32-bit version), i.e. LDR Wt, [Xn, Xm, LSL #2].
CheckValidReg(next_insn & 0x1fu); // Check destination register.
const uint32_t base_reg = BakerReadBarrierFirstRegField::Decode(encoded_data);
CHECK_EQ(next_insn & 0xffe0ffe0u, 0xb8607800u | (base_reg << 5));
CheckValidReg((next_insn >> 16) & 0x1f); // Check index register
break;
}
case BakerReadBarrierKind::kGcRoot: {
DCHECK_GE(literal_offset, 4u);
uint32_t prev_insn = GetInsn(literal_offset - 4u);
// LDR (immediate) with correct root_reg.
const uint32_t root_reg = BakerReadBarrierFirstRegField::Decode(encoded_data);
CHECK_EQ(prev_insn & 0xffc0001fu, 0xb9400000u | root_reg);
break;
}
default:
LOG(FATAL) << "Unexpected kind: " << static_cast<uint32_t>(kind);
UNREACHABLE();
}
}
}
}
void ParallelMoveResolverARM64::PrepareForEmitNativeCode() {
// Note: There are 6 kinds of moves:
// 1. constant -> GPR/FPR (non-cycle)
// 2. constant -> stack (non-cycle)
// 3. GPR/FPR -> GPR/FPR
// 4. GPR/FPR -> stack
// 5. stack -> GPR/FPR
// 6. stack -> stack (non-cycle)
// Case 1, 2 and 6 should never be included in a dependency cycle on ARM64. For case 3, 4, and 5
// VIXL uses at most 1 GPR. VIXL has 2 GPR and 1 FPR temps, and there should be no intersecting
// cycles on ARM64, so we always have 1 GPR and 1 FPR available VIXL temps to resolve the
// dependency.
vixl_temps_.Open(GetVIXLAssembler());
}
void ParallelMoveResolverARM64::FinishEmitNativeCode() {
vixl_temps_.Close();
}
Location ParallelMoveResolverARM64::AllocateScratchLocationFor(Location::Kind kind) {
DCHECK(kind == Location::kRegister || kind == Location::kFpuRegister
|| kind == Location::kStackSlot || kind == Location::kDoubleStackSlot
|| kind == Location::kSIMDStackSlot);
kind = (kind == Location::kFpuRegister || kind == Location::kSIMDStackSlot)
? Location::kFpuRegister
: Location::kRegister;
Location scratch = GetScratchLocation(kind);
if (!scratch.Equals(Location::NoLocation())) {
return scratch;
}
// Allocate from VIXL temp registers.
if (kind == Location::kRegister) {
scratch = LocationFrom(vixl_temps_.AcquireX());
} else {
DCHECK_EQ(kind, Location::kFpuRegister);
scratch = LocationFrom(codegen_->GetGraph()->HasSIMD()
? vixl_temps_.AcquireVRegisterOfSize(kQRegSize)
: vixl_temps_.AcquireD());
}
AddScratchLocation(scratch);
return scratch;
}
void ParallelMoveResolverARM64::FreeScratchLocation(Location loc) {
if (loc.IsRegister()) {
vixl_temps_.Release(XRegisterFrom(loc));
} else {
DCHECK(loc.IsFpuRegister());
vixl_temps_.Release(codegen_->GetGraph()->HasSIMD() ? QRegisterFrom(loc) : DRegisterFrom(loc));
}
RemoveScratchLocation(loc);
}
void ParallelMoveResolverARM64::EmitMove(size_t index) {
MoveOperands* move = moves_[index];
codegen_->MoveLocation(move->GetDestination(), move->GetSource(), DataType::Type::kVoid);
}
void CodeGeneratorARM64::GenerateFrameEntry() {
MacroAssembler* masm = GetVIXLAssembler();
__ Bind(&frame_entry_label_);
if (GetCompilerOptions().CountHotnessInCompiledCode()) {
UseScratchRegisterScope temps(masm);
Register temp = temps.AcquireX();
__ Ldrh(temp, MemOperand(kArtMethodRegister, ArtMethod::HotnessCountOffset().Int32Value()));
__ Add(temp, temp, 1);
__ Strh(temp, MemOperand(kArtMethodRegister, ArtMethod::HotnessCountOffset().Int32Value()));
}
bool do_overflow_check =
FrameNeedsStackCheck(GetFrameSize(), InstructionSet::kArm64) || !IsLeafMethod();
if (do_overflow_check) {
UseScratchRegisterScope temps(masm);
Register temp = temps.AcquireX();
DCHECK(GetCompilerOptions().GetImplicitStackOverflowChecks());
__ Sub(temp, sp, static_cast<int32_t>(GetStackOverflowReservedBytes(InstructionSet::kArm64)));
{
// Ensure that between load and RecordPcInfo there are no pools emitted.
ExactAssemblyScope eas(GetVIXLAssembler(),
kInstructionSize,
CodeBufferCheckScope::kExactSize);
__ ldr(wzr, MemOperand(temp, 0));
RecordPcInfo(nullptr, 0);
}
}
if (!HasEmptyFrame()) {
int frame_size = GetFrameSize();
// Stack layout:
// sp[frame_size - 8] : lr.
// ... : other preserved core registers.
// ... : other preserved fp registers.
// ... : reserved frame space.
// sp[0] : current method.
// Save the current method if we need it. Note that we do not
// do this in HCurrentMethod, as the instruction might have been removed
// in the SSA graph.
if (RequiresCurrentMethod()) {
__ Str(kArtMethodRegister, MemOperand(sp, -frame_size, PreIndex));
} else {
__ Claim(frame_size);
}
GetAssembler()->cfi().AdjustCFAOffset(frame_size);
GetAssembler()->SpillRegisters(GetFramePreservedCoreRegisters(),
frame_size - GetCoreSpillSize());
GetAssembler()->SpillRegisters(GetFramePreservedFPRegisters(),
frame_size - FrameEntrySpillSize());
if (GetGraph()->HasShouldDeoptimizeFlag()) {
// Initialize should_deoptimize flag to 0.
Register wzr = Register(VIXLRegCodeFromART(WZR), kWRegSize);
__ Str(wzr, MemOperand(sp, GetStackOffsetOfShouldDeoptimizeFlag()));
}
}
MaybeGenerateMarkingRegisterCheck(/* code */ __LINE__);
}
void CodeGeneratorARM64::GenerateFrameExit() {
GetAssembler()->cfi().RememberState();
if (!HasEmptyFrame()) {
int frame_size = GetFrameSize();
GetAssembler()->UnspillRegisters(GetFramePreservedFPRegisters(),
frame_size - FrameEntrySpillSize());
GetAssembler()->UnspillRegisters(GetFramePreservedCoreRegisters(),
frame_size - GetCoreSpillSize());
__ Drop(frame_size);
GetAssembler()->cfi().AdjustCFAOffset(-frame_size);
}
__ Ret();
GetAssembler()->cfi().RestoreState();
GetAssembler()->cfi().DefCFAOffset(GetFrameSize());
}
CPURegList CodeGeneratorARM64::GetFramePreservedCoreRegisters() const {
DCHECK(ArtVixlRegCodeCoherentForRegSet(core_spill_mask_, GetNumberOfCoreRegisters(), 0, 0));
return CPURegList(CPURegister::kRegister, kXRegSize,
core_spill_mask_);
}
CPURegList CodeGeneratorARM64::GetFramePreservedFPRegisters() const {
DCHECK(ArtVixlRegCodeCoherentForRegSet(0, 0, fpu_spill_mask_,
GetNumberOfFloatingPointRegisters()));
return CPURegList(CPURegister::kFPRegister, kDRegSize,
fpu_spill_mask_);
}
void CodeGeneratorARM64::Bind(HBasicBlock* block) {
__ Bind(GetLabelOf(block));
}
void CodeGeneratorARM64::MoveConstant(Location location, int32_t value) {
DCHECK(location.IsRegister());
__ Mov(RegisterFrom(location, DataType::Type::kInt32), value);
}
void CodeGeneratorARM64::AddLocationAsTemp(Location location, LocationSummary* locations) {
if (location.IsRegister()) {
locations->AddTemp(location);
} else {
UNIMPLEMENTED(FATAL) << "AddLocationAsTemp not implemented for location " << location;
}
}
void CodeGeneratorARM64::MarkGCCard(Register object, Register value, bool value_can_be_null) {
UseScratchRegisterScope temps(GetVIXLAssembler());
Register card = temps.AcquireX();
Register temp = temps.AcquireW(); // Index within the CardTable - 32bit.
vixl::aarch64::Label done;
if (value_can_be_null) {
__ Cbz(value, &done);
}
__ Ldr(card, MemOperand(tr, Thread::CardTableOffset<kArm64PointerSize>().Int32Value()));
__ Lsr(temp, object, gc::accounting::CardTable::kCardShift);
__ Strb(card, MemOperand(card, temp.X()));
if (value_can_be_null) {
__ Bind(&done);
}
}
void CodeGeneratorARM64::SetupBlockedRegisters() const {
// Blocked core registers:
// lr : Runtime reserved.
// tr : Runtime reserved.
// mr : Runtime reserved.
// ip1 : VIXL core temp.
// ip0 : VIXL core temp.
//
// Blocked fp registers:
// d31 : VIXL fp temp.
CPURegList reserved_core_registers = vixl_reserved_core_registers;
reserved_core_registers.Combine(runtime_reserved_core_registers);
while (!reserved_core_registers.IsEmpty()) {
blocked_core_registers_[reserved_core_registers.PopLowestIndex().GetCode()] = true;
}
CPURegList reserved_fp_registers = vixl_reserved_fp_registers;
while (!reserved_fp_registers.IsEmpty()) {
blocked_fpu_registers_[reserved_fp_registers.PopLowestIndex().GetCode()] = true;
}
if (GetGraph()->IsDebuggable()) {
// Stubs do not save callee-save floating point registers. If the graph
// is debuggable, we need to deal with these registers differently. For
// now, just block them.
CPURegList reserved_fp_registers_debuggable = callee_saved_fp_registers;
while (!reserved_fp_registers_debuggable.IsEmpty()) {
blocked_fpu_registers_[reserved_fp_registers_debuggable.PopLowestIndex().GetCode()] = true;
}
}
}
size_t CodeGeneratorARM64::SaveCoreRegister(size_t stack_index, uint32_t reg_id) {
Register reg = Register(VIXLRegCodeFromART(reg_id), kXRegSize);
__ Str(reg, MemOperand(sp, stack_index));
return kArm64WordSize;
}
size_t CodeGeneratorARM64::RestoreCoreRegister(size_t stack_index, uint32_t reg_id) {
Register reg = Register(VIXLRegCodeFromART(reg_id), kXRegSize);
__ Ldr(reg, MemOperand(sp, stack_index));
return kArm64WordSize;
}
size_t CodeGeneratorARM64::SaveFloatingPointRegister(size_t stack_index, uint32_t reg_id) {
FPRegister reg = FPRegister(reg_id, kDRegSize);
__ Str(reg, MemOperand(sp, stack_index));
return kArm64WordSize;
}
size_t CodeGeneratorARM64::RestoreFloatingPointRegister(size_t stack_index, uint32_t reg_id) {
FPRegister reg = FPRegister(reg_id, kDRegSize);
__ Ldr(reg, MemOperand(sp, stack_index));
return kArm64WordSize;
}
void CodeGeneratorARM64::DumpCoreRegister(std::ostream& stream, int reg) const {
stream << XRegister(reg);
}
void CodeGeneratorARM64::DumpFloatingPointRegister(std::ostream& stream, int reg) const {
stream << DRegister(reg);
}
void CodeGeneratorARM64::MoveConstant(CPURegister destination, HConstant* constant) {
if (constant->IsIntConstant()) {
__ Mov(Register(destination), constant->AsIntConstant()->GetValue());
} else if (constant->IsLongConstant()) {
__ Mov(Register(destination), constant->AsLongConstant()->GetValue());
} else if (constant->IsNullConstant()) {
__ Mov(Register(destination), 0);
} else if (constant->IsFloatConstant()) {
__ Fmov(FPRegister(destination), constant->AsFloatConstant()->GetValue());
} else {
DCHECK(constant->IsDoubleConstant());
__ Fmov(FPRegister(destination), constant->AsDoubleConstant()->GetValue());
}
}
static bool CoherentConstantAndType(Location constant, DataType::Type type) {
DCHECK(constant.IsConstant());
HConstant* cst = constant.GetConstant();
return (cst->IsIntConstant() && type == DataType::Type::kInt32) ||
// Null is mapped to a core W register, which we associate with kPrimInt.
(cst->IsNullConstant() && type == DataType::Type::kInt32) ||
(cst->IsLongConstant() && type == DataType::Type::kInt64) ||
(cst->IsFloatConstant() && type == DataType::Type::kFloat32) ||
(cst->IsDoubleConstant() && type == DataType::Type::kFloat64);
}
// Allocate a scratch register from the VIXL pool, querying first
// the floating-point register pool, and then the core register
// pool. This is essentially a reimplementation of
// vixl::aarch64::UseScratchRegisterScope::AcquireCPURegisterOfSize
// using a different allocation strategy.
static CPURegister AcquireFPOrCoreCPURegisterOfSize(vixl::aarch64::MacroAssembler* masm,
vixl::aarch64::UseScratchRegisterScope* temps,
int size_in_bits) {
return masm->GetScratchFPRegisterList()->IsEmpty()
? CPURegister(temps->AcquireRegisterOfSize(size_in_bits))
: CPURegister(temps->AcquireVRegisterOfSize(size_in_bits));
}
void CodeGeneratorARM64::MoveLocation(Location destination,
Location source,
DataType::Type dst_type) {
if (source.Equals(destination)) {
return;
}
// A valid move can always be inferred from the destination and source
// locations. When moving from and to a register, the argument type can be
// used to generate 32bit instead of 64bit moves. In debug mode we also
// checks the coherency of the locations and the type.
bool unspecified_type = (dst_type == DataType::Type::kVoid);
if (destination.IsRegister() || destination.IsFpuRegister()) {
if (unspecified_type) {
HConstant* src_cst = source.IsConstant() ? source.GetConstant() : nullptr;
if (source.IsStackSlot() ||
(src_cst != nullptr && (src_cst->IsIntConstant()
|| src_cst->IsFloatConstant()
|| src_cst->IsNullConstant()))) {
// For stack slots and 32bit constants, a 64bit type is appropriate.
dst_type = destination.IsRegister() ? DataType::Type::kInt32 : DataType::Type::kFloat32;
} else {
// If the source is a double stack slot or a 64bit constant, a 64bit
// type is appropriate. Else the source is a register, and since the
// type has not been specified, we chose a 64bit type to force a 64bit
// move.
dst_type = destination.IsRegister() ? DataType::Type::kInt64 : DataType::Type::kFloat64;
}
}
DCHECK((destination.IsFpuRegister() && DataType::IsFloatingPointType(dst_type)) ||
(destination.IsRegister() && !DataType::IsFloatingPointType(dst_type)));
CPURegister dst = CPURegisterFrom(destination, dst_type);
if (source.IsStackSlot() || source.IsDoubleStackSlot()) {
DCHECK(dst.Is64Bits() == source.IsDoubleStackSlot());
__ Ldr(dst, StackOperandFrom(source));
} else if (source.IsSIMDStackSlot()) {
__ Ldr(QRegisterFrom(destination), StackOperandFrom(source));
} else if (source.IsConstant()) {
DCHECK(CoherentConstantAndType(source, dst_type));
MoveConstant(dst, source.GetConstant());
} else if (source.IsRegister()) {
if (destination.IsRegister()) {
__ Mov(Register(dst), RegisterFrom(source, dst_type));
} else {
DCHECK(destination.IsFpuRegister());
DataType::Type source_type = DataType::Is64BitType(dst_type)
? DataType::Type::kInt64
: DataType::Type::kInt32;
__ Fmov(FPRegisterFrom(destination, dst_type), RegisterFrom(source, source_type));
}
} else {
DCHECK(source.IsFpuRegister());
if (destination.IsRegister()) {
DataType::Type source_type = DataType::Is64BitType(dst_type)
? DataType::Type::kFloat64
: DataType::Type::kFloat32;
__ Fmov(RegisterFrom(destination, dst_type), FPRegisterFrom(source, source_type));
} else {
DCHECK(destination.IsFpuRegister());
if (GetGraph()->HasSIMD()) {
__ Mov(QRegisterFrom(destination), QRegisterFrom(source));
} else {
__ Fmov(FPRegister(dst), FPRegisterFrom(source, dst_type));
}
}
}
} else if (destination.IsSIMDStackSlot()) {
if (source.IsFpuRegister()) {
__ Str(QRegisterFrom(source), StackOperandFrom(destination));
} else {
DCHECK(source.IsSIMDStackSlot());
UseScratchRegisterScope temps(GetVIXLAssembler());
if (GetVIXLAssembler()->GetScratchFPRegisterList()->IsEmpty()) {
Register temp = temps.AcquireX();
__ Ldr(temp, MemOperand(sp, source.GetStackIndex()));
__ Str(temp, MemOperand(sp, destination.GetStackIndex()));
__ Ldr(temp, MemOperand(sp, source.GetStackIndex() + kArm64WordSize));
__ Str(temp, MemOperand(sp, destination.GetStackIndex() + kArm64WordSize));
} else {
FPRegister temp = temps.AcquireVRegisterOfSize(kQRegSize);
__ Ldr(temp, StackOperandFrom(source));
__ Str(temp, StackOperandFrom(destination));
}
}
} else { // The destination is not a register. It must be a stack slot.
DCHECK(destination.IsStackSlot() || destination.IsDoubleStackSlot());
if (source.IsRegister() || source.IsFpuRegister()) {
if (unspecified_type) {
if (source.IsRegister()) {
dst_type = destination.IsStackSlot() ? DataType::Type::kInt32 : DataType::Type::kInt64;
} else {
dst_type =
destination.IsStackSlot() ? DataType::Type::kFloat32 : DataType::Type::kFloat64;
}
}
DCHECK((destination.IsDoubleStackSlot() == DataType::Is64BitType(dst_type)) &&
(source.IsFpuRegister() == DataType::IsFloatingPointType(dst_type)));
__ Str(CPURegisterFrom(source, dst_type), StackOperandFrom(destination));
} else if (source.IsConstant()) {
DCHECK(unspecified_type || CoherentConstantAndType(source, dst_type))
<< source << " " << dst_type;
UseScratchRegisterScope temps(GetVIXLAssembler());
HConstant* src_cst = source.GetConstant();
CPURegister temp;
if (src_cst->IsZeroBitPattern()) {
temp = (src_cst->IsLongConstant() || src_cst->IsDoubleConstant())
? Register(xzr)
: Register(wzr);
} else {
if (src_cst->IsIntConstant()) {
temp = temps.AcquireW();
} else if (src_cst->IsLongConstant()) {
temp = temps.AcquireX();
} else if (src_cst->IsFloatConstant()) {
temp = temps.AcquireS();
} else {
DCHECK(src_cst->IsDoubleConstant());
temp = temps.AcquireD();
}
MoveConstant(temp, src_cst);
}
__ Str(temp, StackOperandFrom(destination));
} else {
DCHECK(source.IsStackSlot() || source.IsDoubleStackSlot());
DCHECK(source.IsDoubleStackSlot() == destination.IsDoubleStackSlot());
UseScratchRegisterScope temps(GetVIXLAssembler());
// Use any scratch register (a core or a floating-point one)
// from VIXL scratch register pools as a temporary.
//
// We used to only use the FP scratch register pool, but in some
// rare cases the only register from this pool (D31) would
// already be used (e.g. within a ParallelMove instruction, when
// a move is blocked by a another move requiring a scratch FP
// register, which would reserve D31). To prevent this issue, we
// ask for a scratch register of any type (core or FP).
//
// Also, we start by asking for a FP scratch register first, as the
// demand of scratch core registers is higher. This is why we
// use AcquireFPOrCoreCPURegisterOfSize instead of
// UseScratchRegisterScope::AcquireCPURegisterOfSize, which
// allocates core scratch registers first.
CPURegister temp = AcquireFPOrCoreCPURegisterOfSize(
GetVIXLAssembler(),
&temps,
(destination.IsDoubleStackSlot() ? kXRegSize : kWRegSize));
__ Ldr(temp, StackOperandFrom(source));
__ Str(temp, StackOperandFrom(destination));
}
}
}
void CodeGeneratorARM64::Load(DataType::Type type,
CPURegister dst,
const MemOperand& src) {
switch (type) {
case DataType::Type::kBool:
case DataType::Type::kUint8:
__ Ldrb(Register(dst), src);
break;
case DataType::Type::kInt8:
__ Ldrsb(Register(dst), src);
break;
case DataType::Type::kUint16:
__ Ldrh(Register(dst), src);
break;
case DataType::Type::kInt16:
__ Ldrsh(Register(dst), src);
break;
case DataType::Type::kInt32:
case DataType::Type::kReference:
case DataType::Type::kInt64:
case DataType::Type::kFloat32:
case DataType::Type::kFloat64:
DCHECK_EQ(dst.Is64Bits(), DataType::Is64BitType(type));
__ Ldr(dst, src);
break;
case DataType::Type::kUint32:
case DataType::Type::kUint64:
case DataType::Type::kVoid:
LOG(FATAL) << "Unreachable type " << type;
}
}
void CodeGeneratorARM64::LoadAcquire(HInstruction* instruction,
CPURegister dst,
const MemOperand& src,
bool needs_null_check) {
MacroAssembler* masm = GetVIXLAssembler();
UseScratchRegisterScope temps(masm);
Register temp_base = temps.AcquireX();
DataType::Type type = instruction->GetType();
DCHECK(!src.IsPreIndex());
DCHECK(!src.IsPostIndex());
// TODO(vixl): Let the MacroAssembler handle MemOperand.
__ Add(temp_base, src.GetBaseRegister(), OperandFromMemOperand(src));
{
// Ensure that between load and MaybeRecordImplicitNullCheck there are no pools emitted.
MemOperand base = MemOperand(temp_base);
switch (type) {
case DataType::Type::kBool:
case DataType::Type::kUint8:
case DataType::Type::kInt8:
{
ExactAssemblyScope eas(masm, kInstructionSize, CodeBufferCheckScope::kExactSize);
__ ldarb(Register(dst), base);
if (needs_null_check) {
MaybeRecordImplicitNullCheck(instruction);
}
}
if (type == DataType::Type::kInt8) {
__ Sbfx(Register(dst), Register(dst), 0, DataType::Size(type) * kBitsPerByte);
}
break;
case DataType::Type::kUint16:
case DataType::Type::kInt16:
{
ExactAssemblyScope eas(masm, kInstructionSize, CodeBufferCheckScope::kExactSize);
__ ldarh(Register(dst), base);
if (needs_null_check) {
MaybeRecordImplicitNullCheck(instruction);
}
}
if (type == DataType::Type::kInt16) {
__ Sbfx(Register(dst), Register(dst), 0, DataType::Size(type) * kBitsPerByte);
}
break;
case DataType::Type::kInt32:
case DataType::Type::kReference:
case DataType::Type::kInt64:
DCHECK_EQ(dst.Is64Bits(), DataType::Is64BitType(type));
{
ExactAssemblyScope eas(masm, kInstructionSize, CodeBufferCheckScope::kExactSize);
__ ldar(Register(dst), base);
if (needs_null_check) {
MaybeRecordImplicitNullCheck(instruction);
}
}
break;
case DataType::Type::kFloat32:
case DataType::Type::kFloat64: {
DCHECK(dst.IsFPRegister());
DCHECK_EQ(dst.Is64Bits(), DataType::Is64BitType(type));
Register temp = dst.Is64Bits() ? temps.AcquireX() : temps.AcquireW();
{
ExactAssemblyScope eas(masm, kInstructionSize, CodeBufferCheckScope::kExactSize);
__ ldar(temp, base);
if (needs_null_check) {
MaybeRecordImplicitNullCheck(instruction);
}
}
__ Fmov(FPRegister(dst), temp);
break;
}
case DataType::Type::kUint32:
case DataType::Type::kUint64:
case DataType::Type::kVoid:
LOG(FATAL) << "Unreachable type " << type;
}
}
}
void CodeGeneratorARM64::Store(DataType::Type type,
CPURegister src,
const MemOperand& dst) {
switch (type) {
case DataType::Type::kBool:
case DataType::Type::kUint8:
case DataType::Type::kInt8:
__ Strb(Register(src), dst);
break;
case DataType::Type::kUint16:
case DataType::Type::kInt16:
__ Strh(Register(src), dst);
break;
case DataType::Type::kInt32:
case DataType::Type::kReference:
case DataType::Type::kInt64:
case DataType::Type::kFloat32:
case DataType::Type::kFloat64:
DCHECK_EQ(src.Is64Bits(), DataType::Is64BitType(type));
__ Str(src, dst);
break;
case DataType::Type::kUint32:
case DataType::Type::kUint64:
case DataType::Type::kVoid:
LOG(FATAL) << "Unreachable type " << type;
}
}
void CodeGeneratorARM64::StoreRelease(HInstruction* instruction,
DataType::Type type,
CPURegister src,
const MemOperand& dst,
bool needs_null_check) {
MacroAssembler* masm = GetVIXLAssembler();
UseScratchRegisterScope temps(GetVIXLAssembler());
Register temp_base = temps.AcquireX();
DCHECK(!dst.IsPreIndex());
DCHECK(!dst.IsPostIndex());
// TODO(vixl): Let the MacroAssembler handle this.
Operand op = OperandFromMemOperand(dst);
__ Add(temp_base, dst.GetBaseRegister(), op);
MemOperand base = MemOperand(temp_base);
// Ensure that between store and MaybeRecordImplicitNullCheck there are no pools emitted.
switch (type) {
case DataType::Type::kBool:
case DataType::Type::kUint8:
case DataType::Type::kInt8:
{
ExactAssemblyScope eas(masm, kInstructionSize, CodeBufferCheckScope::kExactSize);
__ stlrb(Register(src), base);
if (needs_null_check) {
MaybeRecordImplicitNullCheck(instruction);
}
}
break;
case DataType::Type::kUint16:
case DataType::Type::kInt16:
{
ExactAssemblyScope eas(masm, kInstructionSize, CodeBufferCheckScope::kExactSize);
__ stlrh(Register(src), base);
if (needs_null_check) {
MaybeRecordImplicitNullCheck(instruction);
}
}
break;
case DataType::Type::kInt32:
case DataType::Type::kReference:
case DataType::Type::kInt64:
DCHECK_EQ(src.Is64Bits(), DataType::Is64BitType(type));
{
ExactAssemblyScope eas(masm, kInstructionSize, CodeBufferCheckScope::kExactSize);
__ stlr(Register(src), base);
if (needs_null_check) {
MaybeRecordImplicitNullCheck(instruction);
}
}
break;
case DataType::Type::kFloat32:
case DataType::Type::kFloat64: {
DCHECK_EQ(src.Is64Bits(), DataType::Is64BitType(type));
Register temp_src;
if (src.IsZero()) {
// The zero register is used to avoid synthesizing zero constants.
temp_src = Register(src);
} else {
DCHECK(src.IsFPRegister());
temp_src = src.Is64Bits() ? temps.AcquireX() : temps.AcquireW();
__ Fmov(temp_src, FPRegister(src));
}
{
ExactAssemblyScope eas(masm, kInstructionSize, CodeBufferCheckScope::kExactSize);
__ stlr(temp_src, base);
if (needs_null_check) {
MaybeRecordImplicitNullCheck(instruction);
}
}
break;
}
case DataType::Type::kUint32:
case DataType::Type::kUint64:
case DataType::Type::kVoid:
LOG(FATAL) << "Unreachable type " << type;
}
}
void CodeGeneratorARM64::InvokeRuntime(QuickEntrypointEnum entrypoint,
HInstruction* instruction,
uint32_t dex_pc,
SlowPathCode* slow_path) {
ValidateInvokeRuntime(entrypoint, instruction, slow_path);
__ Ldr(lr, MemOperand(tr, GetThreadOffset<kArm64PointerSize>(entrypoint).Int32Value()));
{
// Ensure the pc position is recorded immediately after the `blr` instruction.
ExactAssemblyScope eas(GetVIXLAssembler(), kInstructionSize, CodeBufferCheckScope::kExactSize);
__ blr(lr);
if (EntrypointRequiresStackMap(entrypoint)) {
RecordPcInfo(instruction, dex_pc, slow_path);
}
}
}
void CodeGeneratorARM64::InvokeRuntimeWithoutRecordingPcInfo(int32_t entry_point_offset,
HInstruction* instruction,
SlowPathCode* slow_path) {
ValidateInvokeRuntimeWithoutRecordingPcInfo(instruction, slow_path);
__ Ldr(lr, MemOperand(tr, entry_point_offset));
__ Blr(lr);
}
void InstructionCodeGeneratorARM64::GenerateClassInitializationCheck(SlowPathCodeARM64* slow_path,
Register class_reg) {
UseScratchRegisterScope temps(GetVIXLAssembler());
Register temp = temps.AcquireW();
constexpr size_t status_lsb_position = SubtypeCheckBits::BitStructSizeOf();
const size_t status_byte_offset =
mirror::Class::StatusOffset().SizeValue() + (status_lsb_position / kBitsPerByte);
constexpr uint32_t shifted_initialized_value =
enum_cast<uint32_t>(ClassStatus::kInitialized) << (status_lsb_position % kBitsPerByte);
// Even if the initialized flag is set, we need to ensure consistent memory ordering.
// TODO(vixl): Let the MacroAssembler handle MemOperand.
__ Add(temp, class_reg, status_byte_offset);
__ Ldarb(temp, HeapOperand(temp));
__ Cmp(temp, shifted_initialized_value);
__ B(lo, slow_path->GetEntryLabel());
__ Bind(slow_path->GetExitLabel());
}
void InstructionCodeGeneratorARM64::GenerateBitstringTypeCheckCompare(
HTypeCheckInstruction* check, vixl::aarch64::Register temp) {
uint32_t path_to_root = check->GetBitstringPathToRoot();
uint32_t mask = check->GetBitstringMask();
DCHECK(IsPowerOfTwo(mask + 1));
size_t mask_bits = WhichPowerOf2(mask + 1);
if (mask_bits == 16u) {
// Load only the bitstring part of the status word.
__ Ldrh(temp, HeapOperand(temp, mirror::Class::StatusOffset()));
} else {
// /* uint32_t */ temp = temp->status_
__ Ldr(temp, HeapOperand(temp, mirror::Class::StatusOffset()));
// Extract the bitstring bits.
__ Ubfx(temp, temp, 0, mask_bits);
}
// Compare the bitstring bits to `path_to_root`.
__ Cmp(temp, path_to_root);
}
void CodeGeneratorARM64::GenerateMemoryBarrier(MemBarrierKind kind) {
BarrierType type = BarrierAll;
switch (kind) {
case MemBarrierKind::kAnyAny:
case MemBarrierKind::kAnyStore: {
type = BarrierAll;
break;
}
case MemBarrierKind::kLoadAny: {
type = BarrierReads;
break;
}
case MemBarrierKind::kStoreStore: {
type = BarrierWrites;
break;
}
default:
LOG(FATAL) << "Unexpected memory barrier " << kind;
}
__ Dmb(InnerShareable, type);
}
void InstructionCodeGeneratorARM64::GenerateSuspendCheck(HSuspendCheck* instruction,
HBasicBlock* successor) {
SuspendCheckSlowPathARM64* slow_path =
down_cast<SuspendCheckSlowPathARM64*>(instruction->GetSlowPath());
if (slow_path == nullptr) {
slow_path =
new (codegen_->GetScopedAllocator()) SuspendCheckSlowPathARM64(instruction, successor);
instruction->SetSlowPath(slow_path);
codegen_->AddSlowPath(slow_path);
if (successor != nullptr) {
DCHECK(successor->IsLoopHeader());
}
} else {
DCHECK_EQ(slow_path->GetSuccessor(), successor);
}
UseScratchRegisterScope temps(codegen_->GetVIXLAssembler());
Register temp = temps.AcquireW();
__ Ldrh(temp, MemOperand(tr, Thread::ThreadFlagsOffset<kArm64PointerSize>().SizeValue()));
if (successor == nullptr) {
__ Cbnz(temp, slow_path->GetEntryLabel());
__ Bind(slow_path->GetReturnLabel());
} else {
__ Cbz(temp, codegen_->GetLabelOf(successor));
__ B(slow_path->GetEntryLabel());
// slow_path will return to GetLabelOf(successor).
}
}
InstructionCodeGeneratorARM64::InstructionCodeGeneratorARM64(HGraph* graph,
CodeGeneratorARM64* codegen)
: InstructionCodeGenerator(graph, codegen),
assembler_(codegen->GetAssembler()),
codegen_(codegen) {}
void LocationsBuilderARM64::HandleBinaryOp(HBinaryOperation* instr) {
DCHECK_EQ(instr->InputCount(), 2U);
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(instr);
DataType::Type type = instr->GetResultType();
switch (type) {
case DataType::Type::kInt32:
case DataType::Type::kInt64:
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, ARM64EncodableConstantOrRegister(instr->InputAt(1), instr));
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
break;
case DataType::Type::kFloat32:
case DataType::Type::kFloat64:
locations->SetInAt(0, Location::RequiresFpuRegister());
locations->SetInAt(1, Location::RequiresFpuRegister());
locations->SetOut(Location::RequiresFpuRegister(), Location::kNoOutputOverlap);
break;
default:
LOG(FATAL) << "Unexpected " << instr->DebugName() << " type " << type;
}
}
void LocationsBuilderARM64::HandleFieldGet(HInstruction* instruction,
const FieldInfo& field_info) {
DCHECK(instruction->IsInstanceFieldGet() || instruction->IsStaticFieldGet());
bool object_field_get_with_read_barrier =
kEmitCompilerReadBarrier && (instruction->GetType() == DataType::Type::kReference);
LocationSummary* locations =
new (GetGraph()->GetAllocator()) LocationSummary(instruction,
object_field_get_with_read_barrier
? LocationSummary::kCallOnSlowPath
: LocationSummary::kNoCall);
if (object_field_get_with_read_barrier && kUseBakerReadBarrier) {
locations->SetCustomSlowPathCallerSaves(RegisterSet::Empty()); // No caller-save registers.
// We need a temporary register for the read barrier marking slow
// path in CodeGeneratorARM64::GenerateFieldLoadWithBakerReadBarrier.
if (kBakerReadBarrierLinkTimeThunksEnableForFields &&
!Runtime::Current()->UseJitCompilation() &&
!field_info.IsVolatile()) {
// If link-time thunks for the Baker read barrier are enabled, for AOT
// non-volatile loads we need a temporary only if the offset is too big.
if (field_info.GetFieldOffset().Uint32Value() >= kReferenceLoadMinFarOffset) {
locations->AddTemp(FixedTempLocation());
}
} else {
locations->AddTemp(Location::RequiresRegister());
}
}
locations->SetInAt(0, Location::RequiresRegister());
if (DataType::IsFloatingPointType(instruction->GetType())) {
locations->SetOut(Location::RequiresFpuRegister());
} else {
// The output overlaps for an object field get when read barriers
// are enabled: we do not want the load to overwrite the object's
// location, as we need it to emit the read barrier.
locations->SetOut(
Location::RequiresRegister(),
object_field_get_with_read_barrier ? Location::kOutputOverlap : Location::kNoOutputOverlap);
}
}
void InstructionCodeGeneratorARM64::HandleFieldGet(HInstruction* instruction,
const FieldInfo& field_info) {
DCHECK(instruction->IsInstanceFieldGet() || instruction->IsStaticFieldGet());
LocationSummary* locations = instruction->GetLocations();
Location base_loc = locations->InAt(0);
Location out = locations->Out();
uint32_t offset = field_info.GetFieldOffset().Uint32Value();
DCHECK_EQ(DataType::Size(field_info.GetFieldType()), DataType::Size(instruction->GetType()));
DataType::Type load_type = instruction->GetType();
MemOperand field = HeapOperand(InputRegisterAt(instruction, 0), field_info.GetFieldOffset());
if (kEmitCompilerReadBarrier && kUseBakerReadBarrier &&
load_type == DataType::Type::kReference) {
// Object FieldGet with Baker's read barrier case.
// /* HeapReference<Object> */ out = *(base + offset)
Register base = RegisterFrom(base_loc, DataType::Type::kReference);
Location maybe_temp =
(locations->GetTempCount() != 0) ? locations->GetTemp(0) : Location::NoLocation();
// Note that potential implicit null checks are handled in this
// CodeGeneratorARM64::GenerateFieldLoadWithBakerReadBarrier call.
codegen_->GenerateFieldLoadWithBakerReadBarrier(
instruction,
out,
base,
offset,
maybe_temp,
/* needs_null_check */ true,
field_info.IsVolatile());
} else {
// General case.
if (field_info.IsVolatile()) {
// Note that a potential implicit null check is handled in this
// CodeGeneratorARM64::LoadAcquire call.
// NB: LoadAcquire will record the pc info if needed.
codegen_->LoadAcquire(
instruction, OutputCPURegister(instruction), field, /* needs_null_check */ true);
} else {
// Ensure that between load and MaybeRecordImplicitNullCheck there are no pools emitted.
EmissionCheckScope guard(GetVIXLAssembler(), kMaxMacroInstructionSizeInBytes);
codegen_->Load(load_type, OutputCPURegister(instruction), field);
codegen_->MaybeRecordImplicitNullCheck(instruction);
}
if (load_type == DataType::Type::kReference) {
// If read barriers are enabled, emit read barriers other than
// Baker's using a slow path (and also unpoison the loaded
// reference, if heap poisoning is enabled).
codegen_->MaybeGenerateReadBarrierSlow(instruction, out, out, base_loc, offset);
}
}
}
void LocationsBuilderARM64::HandleFieldSet(HInstruction* instruction) {
LocationSummary* locations =
new (GetGraph()->GetAllocator()) LocationSummary(instruction, LocationSummary::kNoCall);
locations->SetInAt(0, Location::RequiresRegister());
if (IsConstantZeroBitPattern(instruction->InputAt(1))) {
locations->SetInAt(1, Location::ConstantLocation(instruction->InputAt(1)->AsConstant()));
} else if (DataType::IsFloatingPointType(instruction->InputAt(1)->GetType())) {
locations->SetInAt(1, Location::RequiresFpuRegister());
} else {
locations->SetInAt(1, Location::RequiresRegister());
}
}
void InstructionCodeGeneratorARM64::HandleFieldSet(HInstruction* instruction,
const FieldInfo& field_info,
bool value_can_be_null) {
DCHECK(instruction->IsInstanceFieldSet() || instruction->IsStaticFieldSet());
Register obj = InputRegisterAt(instruction, 0);
CPURegister value = InputCPURegisterOrZeroRegAt(instruction, 1);
CPURegister source = value;
Offset offset = field_info.GetFieldOffset();
DataType::Type field_type = field_info.GetFieldType();
{
// We use a block to end the scratch scope before the write barrier, thus
// freeing the temporary registers so they can be used in `MarkGCCard`.
UseScratchRegisterScope temps(GetVIXLAssembler());
if (kPoisonHeapReferences && field_type == DataType::Type::kReference) {
DCHECK(value.IsW());
Register temp = temps.AcquireW();
__ Mov(temp, value.W());
GetAssembler()->PoisonHeapReference(temp.W());
source = temp;
}
if (field_info.IsVolatile()) {
codegen_->StoreRelease(
instruction, field_type, source, HeapOperand(obj, offset), /* needs_null_check */ true);
} else {
// Ensure that between store and MaybeRecordImplicitNullCheck there are no pools emitted.
EmissionCheckScope guard(GetVIXLAssembler(), kMaxMacroInstructionSizeInBytes);
codegen_->Store(field_type, source, HeapOperand(obj, offset));
codegen_->MaybeRecordImplicitNullCheck(instruction);
}
}
if (CodeGenerator::StoreNeedsWriteBarrier(field_type, instruction->InputAt(1))) {
codegen_->MarkGCCard(obj, Register(value), value_can_be_null);
}
}
void InstructionCodeGeneratorARM64::HandleBinaryOp(HBinaryOperation* instr) {
DataType::Type type = instr->GetType();
switch (type) {
case DataType::Type::kInt32:
case DataType::Type::kInt64: {
Register dst = OutputRegister(instr);
Register lhs = InputRegisterAt(instr, 0);
Operand rhs = InputOperandAt(instr, 1);
if (instr->IsAdd()) {
__ Add(dst, lhs, rhs);
} else if (instr->IsAnd()) {
__ And(dst, lhs, rhs);
} else if (instr->IsOr()) {
__ Orr(dst, lhs, rhs);
} else if (instr->IsSub()) {
__ Sub(dst, lhs, rhs);
} else if (instr->IsRor()) {
if (rhs.IsImmediate()) {
uint32_t shift = rhs.GetImmediate() & (lhs.GetSizeInBits() - 1);
__ Ror(dst, lhs, shift);
} else {
// Ensure shift distance is in the same size register as the result. If
// we are rotating a long and the shift comes in a w register originally,
// we don't need to sxtw for use as an x since the shift distances are
// all & reg_bits - 1.
__ Ror(dst, lhs, RegisterFrom(instr->GetLocations()->InAt(1), type));
}
} else {
DCHECK(instr->IsXor());
__ Eor(dst, lhs, rhs);
}
break;
}
case DataType::Type::kFloat32:
case DataType::Type::kFloat64: {
FPRegister dst = OutputFPRegister(instr);
FPRegister lhs = InputFPRegisterAt(instr, 0);
FPRegister rhs = InputFPRegisterAt(instr, 1);
if (instr->IsAdd()) {
__ Fadd(dst, lhs, rhs);
} else if (instr->IsSub()) {
__ Fsub(dst, lhs, rhs);
} else {
LOG(FATAL) << "Unexpected floating-point binary operation";
}
break;
}
default:
LOG(FATAL) << "Unexpected binary operation type " << type;
}
}
void LocationsBuilderARM64::HandleShift(HBinaryOperation* instr) {
DCHECK(instr->IsShl() || instr->IsShr() || instr->IsUShr());
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(instr);
DataType::Type type = instr->GetResultType();
switch (type) {
case DataType::Type::kInt32:
case DataType::Type::kInt64: {
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RegisterOrConstant(instr->InputAt(1)));
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
break;
}
default:
LOG(FATAL) << "Unexpected shift type " << type;
}
}
void InstructionCodeGeneratorARM64::HandleShift(HBinaryOperation* instr) {
DCHECK(instr->IsShl() || instr->IsShr() || instr->IsUShr());
DataType::Type type = instr->GetType();
switch (type) {
case DataType::Type::kInt32:
case DataType::Type::kInt64: {
Register dst = OutputRegister(instr);
Register lhs = InputRegisterAt(instr, 0);
Operand rhs = InputOperandAt(instr, 1);
if (rhs.IsImmediate()) {
uint32_t shift_value = rhs.GetImmediate() &
(type == DataType::Type::kInt32 ? kMaxIntShiftDistance : kMaxLongShiftDistance);
if (instr->IsShl()) {
__ Lsl(dst, lhs, shift_value);
} else if (instr->IsShr()) {
__ Asr(dst, lhs, shift_value);
} else {
__ Lsr(dst, lhs, shift_value);
}
} else {
Register rhs_reg = dst.IsX() ? rhs.GetRegister().X() : rhs.GetRegister().W();
if (instr->IsShl()) {
__ Lsl(dst, lhs, rhs_reg);
} else if (instr->IsShr()) {
__ Asr(dst, lhs, rhs_reg);
} else {
__ Lsr(dst, lhs, rhs_reg);
}
}
break;
}
default:
LOG(FATAL) << "Unexpected shift operation type " << type;
}
}
void LocationsBuilderARM64::VisitAdd(HAdd* instruction) {
HandleBinaryOp(instruction);
}
void InstructionCodeGeneratorARM64::VisitAdd(HAdd* instruction) {
HandleBinaryOp(instruction);
}
void LocationsBuilderARM64::VisitAnd(HAnd* instruction) {
HandleBinaryOp(instruction);
}
void InstructionCodeGeneratorARM64::VisitAnd(HAnd* instruction) {
HandleBinaryOp(instruction);
}
void LocationsBuilderARM64::VisitBitwiseNegatedRight(HBitwiseNegatedRight* instr) {
DCHECK(DataType::IsIntegralType(instr->GetType())) << instr->GetType();
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(instr);
locations->SetInAt(0, Location::RequiresRegister());
// There is no immediate variant of negated bitwise instructions in AArch64.
locations->SetInAt(1, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
}
void InstructionCodeGeneratorARM64::VisitBitwiseNegatedRight(HBitwiseNegatedRight* instr) {
Register dst = OutputRegister(instr);
Register lhs = InputRegisterAt(instr, 0);
Register rhs = InputRegisterAt(instr, 1);
switch (instr->GetOpKind()) {
case HInstruction::kAnd:
__ Bic(dst, lhs, rhs);
break;
case HInstruction::kOr:
__ Orn(dst, lhs, rhs);
break;
case HInstruction::kXor:
__ Eon(dst, lhs, rhs);
break;
default:
LOG(FATAL) << "Unreachable";
}
}
void LocationsBuilderARM64::VisitDataProcWithShifterOp(
HDataProcWithShifterOp* instruction) {
DCHECK(instruction->GetType() == DataType::Type::kInt32 ||
instruction->GetType() == DataType::Type::kInt64);
LocationSummary* locations =
new (GetGraph()->GetAllocator()) LocationSummary(instruction, LocationSummary::kNoCall);
if (instruction->GetInstrKind() == HInstruction::kNeg) {
locations->SetInAt(0, Location::ConstantLocation(instruction->InputAt(0)->AsConstant()));
} else {
locations->SetInAt(0, Location::RequiresRegister());
}
locations->SetInAt(1, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
}
void InstructionCodeGeneratorARM64::VisitDataProcWithShifterOp(
HDataProcWithShifterOp* instruction) {
DataType::Type type = instruction->GetType();
HInstruction::InstructionKind kind = instruction->GetInstrKind();
DCHECK(type == DataType::Type::kInt32 || type == DataType::Type::kInt64);
Register out = OutputRegister(instruction);
Register left;
if (kind != HInstruction::kNeg) {
left = InputRegisterAt(instruction, 0);
}
// If this `HDataProcWithShifterOp` was created by merging a type conversion as the
// shifter operand operation, the IR generating `right_reg` (input to the type
// conversion) can have a different type from the current instruction's type,
// so we manually indicate the type.
Register right_reg = RegisterFrom(instruction->GetLocations()->InAt(1), type);
Operand right_operand(0);
HDataProcWithShifterOp::OpKind op_kind = instruction->GetOpKind();
if (HDataProcWithShifterOp::IsExtensionOp(op_kind)) {
right_operand = Operand(right_reg, helpers::ExtendFromOpKind(op_kind));
} else {
right_operand = Operand(right_reg,
helpers::ShiftFromOpKind(op_kind),
instruction->GetShiftAmount());
}
// Logical binary operations do not support extension operations in the
// operand. Note that VIXL would still manage if it was passed by generating
// the extension as a separate instruction.
// `HNeg` also does not support extension. See comments in `ShifterOperandSupportsExtension()`.
DCHECK(!right_operand.IsExtendedRegister() ||
(kind != HInstruction::kAnd && kind != HInstruction::kOr && kind != HInstruction::kXor &&
kind != HInstruction::kNeg));
switch (kind) {
case HInstruction::kAdd:
__ Add(out, left, right_operand);
break;
case HInstruction::kAnd:
__ And(out, left, right_operand);
break;
case HInstruction::kNeg:
DCHECK(instruction->InputAt(0)->AsConstant()->IsArithmeticZero());
__ Neg(out, right_operand);
break;
case HInstruction::kOr:
__ Orr(out, left, right_operand);
break;
case HInstruction::kSub:
__ Sub(out, left, right_operand);
break;
case HInstruction::kXor:
__ Eor(out, left, right_operand);
break;
default:
LOG(FATAL) << "Unexpected operation kind: " << kind;
UNREACHABLE();
}
}
void LocationsBuilderARM64::VisitIntermediateAddress(HIntermediateAddress* instruction) {
LocationSummary* locations =
new (GetGraph()->GetAllocator()) LocationSummary(instruction, LocationSummary::kNoCall);
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, ARM64EncodableConstantOrRegister(instruction->GetOffset(), instruction));
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
}
void InstructionCodeGeneratorARM64::VisitIntermediateAddress(HIntermediateAddress* instruction) {
__ Add(OutputRegister(instruction),
InputRegisterAt(instruction, 0),
Operand(InputOperandAt(instruction, 1)));
}
void LocationsBuilderARM64::VisitIntermediateAddressIndex(HIntermediateAddressIndex* instruction) {
LocationSummary* locations =
new (GetGraph()->GetAllocator()) LocationSummary(instruction, LocationSummary::kNoCall);
HIntConstant* shift = instruction->GetShift()->AsIntConstant();
locations->SetInAt(0, Location::RequiresRegister());
// For byte case we don't need to shift the index variable so we can encode the data offset into
// ADD instruction. For other cases we prefer the data_offset to be in register; that will hoist
// data offset constant generation out of the loop and reduce the critical path length in the
// loop.
locations->SetInAt(1, shift->GetValue() == 0
? Location::ConstantLocation(instruction->GetOffset()->AsIntConstant())
: Location::RequiresRegister());
locations->SetInAt(2, Location::ConstantLocation(shift));
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
}
void InstructionCodeGeneratorARM64::VisitIntermediateAddressIndex(
HIntermediateAddressIndex* instruction) {
Register index_reg = InputRegisterAt(instruction, 0);
uint32_t shift = Int64ConstantFrom(instruction->GetLocations()->InAt(2));
uint32_t offset = instruction->GetOffset()->AsIntConstant()->GetValue();
if (shift == 0) {
__ Add(OutputRegister(instruction), index_reg, offset);
} else {
Register offset_reg = InputRegisterAt(instruction, 1);
__ Add(OutputRegister(instruction), offset_reg, Operand(index_reg, LSL, shift));
}
}
void LocationsBuilderARM64::VisitMultiplyAccumulate(HMultiplyAccumulate* instr) {
LocationSummary* locations =
new (GetGraph()->GetAllocator()) LocationSummary(instr, LocationSummary::kNoCall);
HInstruction* accumulator = instr->InputAt(HMultiplyAccumulate::kInputAccumulatorIndex);
if (instr->GetOpKind() == HInstruction::kSub &&
accumulator->IsConstant() &&
accumulator->AsConstant()->IsArithmeticZero()) {
// Don't allocate register for Mneg instruction.
} else {
locations->SetInAt(HMultiplyAccumulate::kInputAccumulatorIndex,
Location::RequiresRegister());
}
locations->SetInAt(HMultiplyAccumulate::kInputMulLeftIndex, Location::RequiresRegister());
locations->SetInAt(HMultiplyAccumulate::kInputMulRightIndex, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
}
void InstructionCodeGeneratorARM64::VisitMultiplyAccumulate(HMultiplyAccumulate* instr) {
Register res = OutputRegister(instr);
Register mul_left = InputRegisterAt(instr, HMultiplyAccumulate::kInputMulLeftIndex);
Register mul_right = InputRegisterAt(instr, HMultiplyAccumulate::kInputMulRightIndex);
// Avoid emitting code that could trigger Cortex A53's erratum 835769.
// This fixup should be carried out for all multiply-accumulate instructions:
// madd, msub, smaddl, smsubl, umaddl and umsubl.
if (instr->GetType() == DataType::Type::kInt64 &&
codegen_->GetInstructionSetFeatures().NeedFixCortexA53_835769()) {
MacroAssembler* masm = down_cast<CodeGeneratorARM64*>(codegen_)->GetVIXLAssembler();
vixl::aarch64::Instruction* prev =
masm->GetCursorAddress<vixl::aarch64::Instruction*>() - kInstructionSize;
if (prev->IsLoadOrStore()) {
// Make sure we emit only exactly one nop.
ExactAssemblyScope scope(masm, kInstructionSize, CodeBufferCheckScope::kExactSize);
__ nop();
}
}
if (instr->GetOpKind() == HInstruction::kAdd) {
Register accumulator = InputRegisterAt(instr, HMultiplyAccumulate::kInputAccumulatorIndex);
__ Madd(res, mul_left, mul_right, accumulator);
} else {
DCHECK(instr->GetOpKind() == HInstruction::kSub);
HInstruction* accum_instr = instr->InputAt(HMultiplyAccumulate::kInputAccumulatorIndex);
if (accum_instr->IsConstant() && accum_instr->AsConstant()->IsArithmeticZero()) {
__ Mneg(res, mul_left, mul_right);
} else {
Register accumulator = InputRegisterAt(instr, HMultiplyAccumulate::kInputAccumulatorIndex);
__ Msub(res, mul_left, mul_right, accumulator);
}
}
}
void LocationsBuilderARM64::VisitArrayGet(HArrayGet* instruction) {
bool object_array_get_with_read_barrier =
kEmitCompilerReadBarrier && (instruction->GetType() == DataType::Type::kReference);
LocationSummary* locations =
new (GetGraph()->GetAllocator()) LocationSummary(instruction,
object_array_get_with_read_barrier
? LocationSummary::kCallOnSlowPath
: LocationSummary::kNoCall);
if (object_array_get_with_read_barrier && kUseBakerReadBarrier) {
locations->SetCustomSlowPathCallerSaves(RegisterSet::Empty()); // No caller-save registers.
// We need a temporary register for the read barrier marking slow
// path in CodeGeneratorARM64::GenerateArrayLoadWithBakerReadBarrier.
if (kBakerReadBarrierLinkTimeThunksEnableForFields &&
!Runtime::Current()->UseJitCompilation() &&
instruction->GetIndex()->IsConstant()) {
// Array loads with constant index are treated as field loads.
// If link-time thunks for the Baker read barrier are enabled, for AOT
// constant index loads we need a temporary only if the offset is too big.
uint32_t offset = CodeGenerator::GetArrayDataOffset(instruction);
uint32_t index = instruction->GetIndex()->AsIntConstant()->GetValue();
offset += index << DataType::SizeShift(DataType::Type::kReference);
if (offset >= kReferenceLoadMinFarOffset) {
locations->AddTemp(FixedTempLocation());
}
} else {
locations->AddTemp(Location::RequiresRegister());
}
}
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RegisterOrConstant(instruction->InputAt(1)));
if (DataType::IsFloatingPointType(instruction->GetType())) {
locations->SetOut(Location::RequiresFpuRegister(), Location::kNoOutputOverlap);
} else {
// The output overlaps in the case of an object array get with
// read barriers enabled: we do not want the move to overwrite the
// array's location, as we need it to emit the read barrier.
locations->SetOut(
Location::RequiresRegister(),
object_array_get_with_read_barrier ? Location::kOutputOverlap : Location::kNoOutputOverlap);
}
}
void InstructionCodeGeneratorARM64::VisitArrayGet(HArrayGet* instruction) {
DataType::Type type = instruction->GetType();
Register obj = InputRegisterAt(instruction, 0);
LocationSummary* locations = instruction->GetLocations();
Location index = locations->InAt(1);
Location out = locations->Out();
uint32_t offset = CodeGenerator::GetArrayDataOffset(instruction);
const bool maybe_compressed_char_at = mirror::kUseStringCompression &&
instruction->IsStringCharAt();
MacroAssembler* masm = GetVIXLAssembler();
UseScratchRegisterScope temps(masm);
// The read barrier instrumentation of object ArrayGet instructions
// does not support the HIntermediateAddress instruction.
DCHECK(!((type == DataType::Type::kReference) &&
instruction->GetArray()->IsIntermediateAddress() &&
kEmitCompilerReadBarrier));
if (type == DataType::Type::kReference && kEmitCompilerReadBarrier && kUseBakerReadBarrier) {
// Object ArrayGet with Baker's read barrier case.
// Note that a potential implicit null check is handled in the
// CodeGeneratorARM64::GenerateArrayLoadWithBakerReadBarrier call.
DCHECK(!instruction->CanDoImplicitNullCheckOn(instruction->InputAt(0)));
if (index.IsConstant()) {
// Array load with a constant index can be treated as a field load.
offset += Int64ConstantFrom(index) << DataType::SizeShift(type);
Location maybe_temp =
(locations->GetTempCount() != 0) ? locations->GetTemp(0) : Location::NoLocation();
codegen_->GenerateFieldLoadWithBakerReadBarrier(instruction,
out,
obj.W(),
offset,
maybe_temp,
/* needs_null_check */ false,
/* use_load_acquire */ false);
} else {
Register temp = WRegisterFrom(locations->GetTemp(0));
codegen_->GenerateArrayLoadWithBakerReadBarrier(
instruction, out, obj.W(), offset, index, temp, /* needs_null_check */ false);
}
} else {
// General case.
MemOperand source = HeapOperand(obj);
Register length;
if (maybe_compressed_char_at) {
uint32_t count_offset = mirror::String::CountOffset().Uint32Value();
length = temps.AcquireW();
{
// Ensure that between load and MaybeRecordImplicitNullCheck there are no pools emitted.
EmissionCheckScope guard(GetVIXLAssembler(), kMaxMacroInstructionSizeInBytes);
if (instruction->GetArray()->IsIntermediateAddress()) {
DCHECK_LT(count_offset, offset);
int64_t adjusted_offset =
static_cast<int64_t>(count_offset) - static_cast<int64_t>(offset);
// Note that `adjusted_offset` is negative, so this will be a LDUR.
__ Ldr(length, MemOperand(obj.X(), adjusted_offset));
} else {
__ Ldr(length, HeapOperand(obj, count_offset));
}
codegen_->MaybeRecordImplicitNullCheck(instruction);
}
}
if (index.IsConstant()) {
if (maybe_compressed_char_at) {
vixl::aarch64::Label uncompressed_load, done;
static_assert(static_cast<uint32_t>(mirror::StringCompressionFlag::kCompressed) == 0u,
"Expecting 0=compressed, 1=uncompressed");
__ Tbnz(length.W(), 0, &uncompressed_load);
__ Ldrb(Register(OutputCPURegister(instruction)),
HeapOperand(obj, offset + Int64ConstantFrom(index)));
__ B(&done);
__ Bind(&uncompressed_load);
__ Ldrh(Register(OutputCPURegister(instruction)),
HeapOperand(obj, offset + (Int64ConstantFrom(index) << 1)));
__ Bind(&done);
} else {
offset += Int64ConstantFrom(index) << DataType::SizeShift(type);
source = HeapOperand(obj, offset);
}
} else {
Register temp = temps.AcquireSameSizeAs(obj);
if (instruction->GetArray()->IsIntermediateAddress()) {
// We do not need to compute the intermediate address from the array: the
// input instruction has done it already. See the comment in
// `TryExtractArrayAccessAddress()`.
if (kIsDebugBuild) {
HIntermediateAddress* tmp = instruction->GetArray()->AsIntermediateAddress();
DCHECK_EQ(tmp->GetOffset()->AsIntConstant()->GetValueAsUint64(), offset);
}
temp = obj;
} else {
__ Add(temp, obj, offset);
}
if (maybe_compressed_char_at) {
vixl::aarch64::Label uncompressed_load, done;
static_assert(static_cast<uint32_t>(mirror::StringCompressionFlag::kCompressed) == 0u,
"Expecting 0=compressed, 1=uncompressed");
__ Tbnz(length.W(), 0, &uncompressed_load);
__ Ldrb(Register(OutputCPURegister(instruction)),
HeapOperand(temp, XRegisterFrom(index), LSL, 0));
__ B(&done);
__ Bind(&uncompressed_load);
__ Ldrh(Register(OutputCPURegister(instruction)),
HeapOperand(temp, XRegisterFrom(index), LSL, 1));
__ Bind(&done);
} else {
source = HeapOperand(temp, XRegisterFrom(index), LSL, DataType::SizeShift(type));
}
}
if (!maybe_compressed_char_at) {
// Ensure that between load and MaybeRecordImplicitNullCheck there are no pools emitted.
EmissionCheckScope guard(GetVIXLAssembler(), kMaxMacroInstructionSizeInBytes);
codegen_->Load(type, OutputCPURegister(instruction), source);
codegen_->MaybeRecordImplicitNullCheck(instruction);
}
if (type == DataType::Type::kReference) {
static_assert(
sizeof(mirror::HeapReference<mirror::Object>) == sizeof(int32_t),
"art::mirror::HeapReference<art::mirror::Object> and int32_t have different sizes.");
Location obj_loc = locations->InAt(0);
if (index.IsConstant()) {
codegen_->MaybeGenerateReadBarrierSlow(instruction, out, out, obj_loc, offset);
} else {
codegen_->MaybeGenerateReadBarrierSlow(instruction, out, out, obj_loc, offset, index);
}
}
}
}
void LocationsBuilderARM64::VisitArrayLength(HArrayLength* instruction) {
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(instruction);
locations->SetInAt(0, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
}
void InstructionCodeGeneratorARM64::VisitArrayLength(HArrayLength* instruction) {
uint32_t offset = CodeGenerator::GetArrayLengthOffset(instruction);
vixl::aarch64::Register out = OutputRegister(instruction);
{
// Ensure that between load and MaybeRecordImplicitNullCheck there are no pools emitted.
EmissionCheckScope guard(GetVIXLAssembler(), kMaxMacroInstructionSizeInBytes);
__ Ldr(out, HeapOperand(InputRegisterAt(instruction, 0), offset));
codegen_->MaybeRecordImplicitNullCheck(instruction);
}
// Mask out compression flag from String's array length.
if (mirror::kUseStringCompression && instruction->IsStringLength()) {
__ Lsr(out.W(), out.W(), 1u);
}
}
void LocationsBuilderARM64::VisitArraySet(HArraySet* instruction) {
DataType::Type value_type = instruction->GetComponentType();
bool may_need_runtime_call_for_type_check = instruction->NeedsTypeCheck();
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(
instruction,
may_need_runtime_call_for_type_check ?
LocationSummary::kCallOnSlowPath :
LocationSummary::kNoCall);
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RegisterOrConstant(instruction->InputAt(1)));
if (IsConstantZeroBitPattern(instruction->InputAt(2))) {
locations->SetInAt(2, Location::ConstantLocation(instruction->InputAt(2)->AsConstant()));
} else if (DataType::IsFloatingPointType(value_type)) {
locations->SetInAt(2, Location::RequiresFpuRegister());
} else {
locations->SetInAt(2, Location::RequiresRegister());
}
}
void InstructionCodeGeneratorARM64::VisitArraySet(HArraySet* instruction) {
DataType::Type value_type = instruction->GetComponentType();
LocationSummary* locations = instruction->GetLocations();
bool may_need_runtime_call_for_type_check = instruction->NeedsTypeCheck();
bool needs_write_barrier =
CodeGenerator::StoreNeedsWriteBarrier(value_type, instruction->GetValue());
Register array = InputRegisterAt(instruction, 0);
CPURegister value = InputCPURegisterOrZeroRegAt(instruction, 2);
CPURegister source = value;
Location index = locations->InAt(1);
size_t offset = mirror::Array::DataOffset(DataType::Size(value_type)).Uint32Value();
MemOperand destination = HeapOperand(array);
MacroAssembler* masm = GetVIXLAssembler();
if (!needs_write_barrier) {
DCHECK(!may_need_runtime_call_for_type_check);
if (index.IsConstant()) {
offset += Int64ConstantFrom(index) << DataType::SizeShift(value_type);
destination = HeapOperand(array, offset);
} else {
UseScratchRegisterScope temps(masm);
Register temp = temps.AcquireSameSizeAs(array);
if (instruction->GetArray()->IsIntermediateAddress()) {
// We do not need to compute the intermediate address from the array: the
// input instruction has done it already. See the comment in
// `TryExtractArrayAccessAddress()`.
if (kIsDebugBuild) {
HIntermediateAddress* tmp = instruction->GetArray()->AsIntermediateAddress();
DCHECK(tmp->GetOffset()->AsIntConstant()->GetValueAsUint64() == offset);
}
temp = array;
} else {
__ Add(temp, array, offset);
}
destination = HeapOperand(temp,
XRegisterFrom(index),
LSL,
DataType::SizeShift(value_type));
}
{
// Ensure that between store and MaybeRecordImplicitNullCheck there are no pools emitted.
EmissionCheckScope guard(GetVIXLAssembler(), kMaxMacroInstructionSizeInBytes);
codegen_->Store(value_type, value, destination);
codegen_->MaybeRecordImplicitNullCheck(instruction);
}
} else {
DCHECK(!instruction->GetArray()->IsIntermediateAddress());
vixl::aarch64::Label done;
SlowPathCodeARM64* slow_path = nullptr;
{
// We use a block to end the scratch scope before the write barrier, thus
// freeing the temporary registers so they can be used in `MarkGCCard`.
UseScratchRegisterScope temps(masm);
Register temp = temps.AcquireSameSizeAs(array);
if (index.IsConstant()) {
offset += Int64ConstantFrom(index) << DataType::SizeShift(value_type);
destination = HeapOperand(array, offset);
} else {
destination = HeapOperand(temp,
XRegisterFrom(index),
LSL,
DataType::SizeShift(value_type));
}
uint32_t class_offset = mirror::Object::ClassOffset().Int32Value();
uint32_t super_offset = mirror::Class::SuperClassOffset().Int32Value();
uint32_t component_offset = mirror::Class::ComponentTypeOffset().Int32Value();
if (may_need_runtime_call_for_type_check) {
slow_path = new (codegen_->GetScopedAllocator()) ArraySetSlowPathARM64(instruction);
codegen_->AddSlowPath(slow_path);
if (instruction->GetValueCanBeNull()) {
vixl::aarch64::Label non_zero;
__ Cbnz(Register(value), &non_zero);
if (!index.IsConstant()) {
__ Add(temp, array, offset);
}
{
// Ensure that between store and MaybeRecordImplicitNullCheck there are no pools
// emitted.
EmissionCheckScope guard(GetVIXLAssembler(), kMaxMacroInstructionSizeInBytes);
__ Str(wzr, destination);
codegen_->MaybeRecordImplicitNullCheck(instruction);
}
__ B(&done);
__ Bind(&non_zero);
}
// Note that when Baker read barriers are enabled, the type
// checks are performed without read barriers. This is fine,
// even in the case where a class object is in the from-space
// after the flip, as a comparison involving such a type would
// not produce a false positive; it may of course produce a
// false negative, in which case we would take the ArraySet
// slow path.
Register temp2 = temps.AcquireSameSizeAs(array);
// /* HeapReference<Class> */ temp = array->klass_
{
// Ensure that between load and MaybeRecordImplicitNullCheck there are no pools emitted.
EmissionCheckScope guard(GetVIXLAssembler(), kMaxMacroInstructionSizeInBytes);
__ Ldr(temp, HeapOperand(array, class_offset));
codegen_->MaybeRecordImplicitNullCheck(instruction);
}
GetAssembler()->MaybeUnpoisonHeapReference(temp);
// /* HeapReference<Class> */ temp = temp->component_type_
__ Ldr(temp, HeapOperand(temp, component_offset));
// /* HeapReference<Class> */ temp2 = value->klass_
__ Ldr(temp2, HeapOperand(Register(value), class_offset));
// If heap poisoning is enabled, no need to unpoison `temp`
// nor `temp2`, as we are comparing two poisoned references.
__ Cmp(temp, temp2);
temps.Release(temp2);
if (instruction->StaticTypeOfArrayIsObjectArray()) {
vixl::aarch64::Label do_put;
__ B(eq, &do_put);
// If heap poisoning is enabled, the `temp` reference has
// not been unpoisoned yet; unpoison it now.
GetAssembler()->MaybeUnpoisonHeapReference(temp);
// /* HeapReference<Class> */ temp = temp->super_class_
__ Ldr(temp, HeapOperand(temp, super_offset));
// If heap poisoning is enabled, no need to unpoison
// `temp`, as we are comparing against null below.
__ Cbnz(temp, slow_path->GetEntryLabel());
__ Bind(&do_put);
} else {
__ B(ne, slow_path->GetEntryLabel());
}
}
if (kPoisonHeapReferences) {
Register temp2 = temps.AcquireSameSizeAs(array);
DCHECK(value.IsW());
__ Mov(temp2, value.W());
GetAssembler()->PoisonHeapReference(temp2);
source = temp2;
}
if (!index.IsConstant()) {
__ Add(temp, array, offset);
} else {
// We no longer need the `temp` here so release it as the store below may
// need a scratch register (if the constant index makes the offset too large)
// and the poisoned `source` could be using the other scratch register.
temps.Release(temp);
}
{
// Ensure that between store and MaybeRecordImplicitNullCheck there are no pools emitted.
EmissionCheckScope guard(GetVIXLAssembler(), kMaxMacroInstructionSizeInBytes);
__ Str(source, destination);
if (!may_need_runtime_call_for_type_check) {
codegen_->MaybeRecordImplicitNullCheck(instruction);
}
}
}
codegen_->MarkGCCard(array, value.W(), instruction->GetValueCanBeNull());
if (done.IsLinked()) {
__ Bind(&done);
}
if (slow_path != nullptr) {
__ Bind(slow_path->GetExitLabel());
}
}
}
void LocationsBuilderARM64::VisitBoundsCheck(HBoundsCheck* instruction) {
RegisterSet caller_saves = RegisterSet::Empty();
InvokeRuntimeCallingConvention calling_convention;
caller_saves.Add(Location::RegisterLocation(calling_convention.GetRegisterAt(0).GetCode()));
caller_saves.Add(Location::RegisterLocation(calling_convention.GetRegisterAt(1).GetCode()));
LocationSummary* locations = codegen_->CreateThrowingSlowPathLocations(instruction, caller_saves);
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, ARM64EncodableConstantOrRegister(instruction->InputAt(1), instruction));
}
void InstructionCodeGeneratorARM64::VisitBoundsCheck(HBoundsCheck* instruction) {
BoundsCheckSlowPathARM64* slow_path =
new (codegen_->GetScopedAllocator()) BoundsCheckSlowPathARM64(instruction);
codegen_->AddSlowPath(slow_path);
__ Cmp(InputRegisterAt(instruction, 0), InputOperandAt(instruction, 1));
__ B(slow_path->GetEntryLabel(), hs);
}
void LocationsBuilderARM64::VisitClinitCheck(HClinitCheck* check) {
LocationSummary* locations =
new (GetGraph()->GetAllocator()) LocationSummary(check, LocationSummary::kCallOnSlowPath);
locations->SetInAt(0, Location::RequiresRegister());
if (check->HasUses()) {
locations->SetOut(Location::SameAsFirstInput());
}
}
void InstructionCodeGeneratorARM64::VisitClinitCheck(HClinitCheck* check) {
// We assume the class is not null.
SlowPathCodeARM64* slow_path = new (codegen_->GetScopedAllocator()) LoadClassSlowPathARM64(
check->GetLoadClass(), check, check->GetDexPc(), true);
codegen_->AddSlowPath(slow_path);
GenerateClassInitializationCheck(slow_path, InputRegisterAt(check, 0));
}
static bool IsFloatingPointZeroConstant(HInstruction* inst) {
return (inst->IsFloatConstant() && (inst->AsFloatConstant()->IsArithmeticZero()))
|| (inst->IsDoubleConstant() && (inst->AsDoubleConstant()->IsArithmeticZero()));
}
void InstructionCodeGeneratorARM64::GenerateFcmp(HInstruction* instruction) {
FPRegister lhs_reg = InputFPRegisterAt(instruction, 0);
Location rhs_loc = instruction->GetLocations()->InAt(1);
if (rhs_loc.IsConstant()) {
// 0.0 is the only immediate that can be encoded directly in
// an FCMP instruction.
//
// Both the JLS (section 15.20.1) and the JVMS (section 6.5)
// specify that in a floating-point comparison, positive zero
// and negative zero are considered equal, so we can use the
// literal 0.0 for both cases here.
//
// Note however that some methods (Float.equal, Float.compare,
// Float.compareTo, Double.equal, Double.compare,
// Double.compareTo, Math.max, Math.min, StrictMath.max,
// StrictMath.min) consider 0.0 to be (strictly) greater than
// -0.0. So if we ever translate calls to these methods into a
// HCompare instruction, we must handle the -0.0 case with
// care here.
DCHECK(IsFloatingPointZeroConstant(rhs_loc.GetConstant()));
__ Fcmp(lhs_reg, 0.0);
} else {
__ Fcmp(lhs_reg, InputFPRegisterAt(instruction, 1));
}
}
void LocationsBuilderARM64::VisitCompare(HCompare* compare) {
LocationSummary* locations =
new (GetGraph()->GetAllocator()) LocationSummary(compare, LocationSummary::kNoCall);
DataType::Type in_type = compare->InputAt(0)->GetType();
switch (in_type) {
case DataType::Type::kBool:
case DataType::Type::kUint8:
case DataType::Type::kInt8:
case DataType::Type::kUint16:
case DataType::Type::kInt16:
case DataType::Type::kInt32:
case DataType::Type::kInt64: {
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, ARM64EncodableConstantOrRegister(compare->InputAt(1), compare));
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
break;
}
case DataType::Type::kFloat32:
case DataType::Type::kFloat64: {
locations->SetInAt(0, Location::RequiresFpuRegister());
locations->SetInAt(1,
IsFloatingPointZeroConstant(compare->InputAt(1))
? Location::ConstantLocation(compare->InputAt(1)->AsConstant())
: Location::RequiresFpuRegister());
locations->SetOut(Location::RequiresRegister());
break;
}
default:
LOG(FATAL) << "Unexpected type for compare operation " << in_type;
}
}
void InstructionCodeGeneratorARM64::VisitCompare(HCompare* compare) {
DataType::Type in_type = compare->InputAt(0)->GetType();
// 0 if: left == right
// 1 if: left > right
// -1 if: left < right
switch (in_type) {
case DataType::Type::kBool:
case DataType::Type::kUint8:
case DataType::Type::kInt8:
case DataType::Type::kUint16:
case DataType::Type::kInt16:
case DataType::Type::kInt32:
case DataType::Type::kInt64: {
Register result = OutputRegister(compare);
Register left = InputRegisterAt(compare, 0);
Operand right = InputOperandAt(compare, 1);
__ Cmp(left, right);
__ Cset(result, ne); // result == +1 if NE or 0 otherwise
__ Cneg(result, result, lt); // result == -1 if LT or unchanged otherwise
break;
}
case DataType::Type::kFloat32:
case DataType::Type::kFloat64: {
Register result = OutputRegister(compare);
GenerateFcmp(compare);
__ Cset(result, ne);
__ Cneg(result, result, ARM64FPCondition(kCondLT, compare->IsGtBias()));
break;
}
default:
LOG(FATAL) << "Unimplemented compare type " << in_type;
}
}
void LocationsBuilderARM64::HandleCondition(HCondition* instruction) {
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(instruction);
if (DataType::IsFloatingPointType(instruction->InputAt(0)->GetType())) {
locations->SetInAt(0, Location::RequiresFpuRegister());
locations->SetInAt(1,
IsFloatingPointZeroConstant(instruction->InputAt(1))
? Location::ConstantLocation(instruction->InputAt(1)->AsConstant())
: Location::RequiresFpuRegister());
} else {
// Integer cases.
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, ARM64EncodableConstantOrRegister(instruction->InputAt(1), instruction));
}
if (!instruction->IsEmittedAtUseSite()) {
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
}
}
void InstructionCodeGeneratorARM64::HandleCondition(HCondition* instruction) {
if (instruction->IsEmittedAtUseSite()) {
return;
}
LocationSummary* locations = instruction->GetLocations();
Register res = RegisterFrom(locations->Out(), instruction->GetType());
IfCondition if_cond = instruction->GetCondition();
if (DataType::IsFloatingPointType(instruction->InputAt(0)->GetType())) {
GenerateFcmp(instruction);
__ Cset(res, ARM64FPCondition(if_cond, instruction->IsGtBias()));
} else {
// Integer cases.
Register lhs = InputRegisterAt(instruction, 0);
Operand rhs = InputOperandAt(instruction, 1);
__ Cmp(lhs, rhs);
__ Cset(res, ARM64Condition(if_cond));
}
}
#define FOR_EACH_CONDITION_INSTRUCTION(M) \
M(Equal) \
M(NotEqual) \
M(LessThan) \
M(LessThanOrEqual) \
M(GreaterThan) \
M(GreaterThanOrEqual) \
M(Below) \
M(BelowOrEqual) \
M(Above) \
M(AboveOrEqual)
#define DEFINE_CONDITION_VISITORS(Name) \
void LocationsBuilderARM64::Visit##Name(H##Name* comp) { HandleCondition(comp); } \
void InstructionCodeGeneratorARM64::Visit##Name(H##Name* comp) { HandleCondition(comp); }
FOR_EACH_CONDITION_INSTRUCTION(DEFINE_CONDITION_VISITORS)
#undef DEFINE_CONDITION_VISITORS
#undef FOR_EACH_CONDITION_INSTRUCTION
void InstructionCodeGeneratorARM64::DivRemOneOrMinusOne(HBinaryOperation* instruction) {
DCHECK(instruction->IsDiv() || instruction->IsRem());
LocationSummary* locations = instruction->GetLocations();
Location second = locations->InAt(1);
DCHECK(second.IsConstant());
Register out = OutputRegister(instruction);
Register dividend = InputRegisterAt(instruction, 0);
int64_t imm = Int64FromConstant(second.GetConstant());
DCHECK(imm == 1 || imm == -1);
if (instruction->IsRem()) {
__ Mov(out, 0);
} else {
if (imm == 1) {
__ Mov(out, dividend);
} else {
__ Neg(out, dividend);
}
}
}
void InstructionCodeGeneratorARM64::DivRemByPowerOfTwo(HBinaryOperation* instruction) {
DCHECK(instruction->IsDiv() || instruction->IsRem());
LocationSummary* locations = instruction->GetLocations();
Location second = locations->InAt(1);
DCHECK(second.IsConstant());
Register out = OutputRegister(instruction);
Register dividend = InputRegisterAt(instruction, 0);
int64_t imm = Int64FromConstant(second.GetConstant());
uint64_t abs_imm = static_cast<uint64_t>(AbsOrMin(imm));
int ctz_imm = CTZ(abs_imm);
UseScratchRegisterScope temps(GetVIXLAssembler());
Register temp = temps.AcquireSameSizeAs(out);
if (instruction->IsDiv()) {
__ Add(temp, dividend, abs_imm - 1);
__ Cmp(dividend, 0);
__ Csel(out, temp, dividend, lt);
if (imm > 0) {
__ Asr(out, out, ctz_imm);
} else {
__ Neg(out, Operand(out, ASR, ctz_imm));
}
} else {
int bits = instruction->GetResultType() == DataType::Type::kInt32 ? 32 : 64;
__ Asr(temp, dividend, bits - 1);
__ Lsr(temp, temp, bits - ctz_imm);
__ Add(out, dividend, temp);
__ And(out, out, abs_imm - 1);
__ Sub(out, out, temp);
}
}
void InstructionCodeGeneratorARM64::GenerateDivRemWithAnyConstant(HBinaryOperation* instruction) {
DCHECK(instruction->IsDiv() || instruction->IsRem());
LocationSummary* locations = instruction->GetLocations();
Location second = locations->InAt(1);
DCHECK(second.IsConstant());
Register out = OutputRegister(instruction);
Register dividend = InputRegisterAt(instruction, 0);
int64_t imm = Int64FromConstant(second.GetConstant());
DataType::Type type = instruction->GetResultType();
DCHECK(type == DataType::Type::kInt32 || type == DataType::Type::kInt64);
int64_t magic;
int shift;
CalculateMagicAndShiftForDivRem(
imm, type == DataType::Type::kInt64 /* is_long */, &magic, &shift);
UseScratchRegisterScope temps(GetVIXLAssembler());
Register temp = temps.AcquireSameSizeAs(out);
// temp = get_high(dividend * magic)
__ Mov(temp, magic);
if (type == DataType::Type::kInt64) {
__ Smulh(temp, dividend, temp);
} else {
__ Smull(temp.X(), dividend, temp);
__ Lsr(temp.X(), temp.X(), 32);
}
if (imm > 0 && magic < 0) {
__ Add(temp, temp, dividend);
} else if (imm < 0 && magic > 0) {
__ Sub(temp, temp, dividend);
}
if (shift != 0) {
__ Asr(temp, temp, shift);
}
if (instruction->IsDiv()) {
__ Sub(out, temp, Operand(temp, ASR, type == DataType::Type::kInt64 ? 63 : 31));
} else {
__ Sub(temp, temp, Operand(temp, ASR, type == DataType::Type::kInt64 ? 63 : 31));
// TODO: Strength reduction for msub.
Register temp_imm = temps.AcquireSameSizeAs(out);
__ Mov(temp_imm, imm);
__ Msub(out, temp, temp_imm, dividend);
}
}
void InstructionCodeGeneratorARM64::GenerateDivRemIntegral(HBinaryOperation* instruction) {
DCHECK(instruction->IsDiv() || instruction->IsRem());
DataType::Type type = instruction->GetResultType();
DCHECK(type == DataType::Type::kInt32 || type == DataType::Type::kInt64);
LocationSummary* locations = instruction->GetLocations();
Register out = OutputRegister(instruction);
Location second = locations->InAt(1);
if (second.IsConstant()) {
int64_t imm = Int64FromConstant(second.GetConstant());
if (imm == 0) {
// Do not generate anything. DivZeroCheck would prevent any code to be executed.
} else if (imm == 1 || imm == -1) {
DivRemOneOrMinusOne(instruction);
} else if (IsPowerOfTwo(AbsOrMin(imm))) {
DivRemByPowerOfTwo(instruction);
} else {
DCHECK(imm <= -2 || imm >= 2);
GenerateDivRemWithAnyConstant(instruction);
}
} else {
Register dividend = InputRegisterAt(instruction, 0);
Register divisor = InputRegisterAt(instruction, 1);
if (instruction->IsDiv()) {
__ Sdiv(out, dividend, divisor);
} else {
UseScratchRegisterScope temps(GetVIXLAssembler());
Register temp = temps.AcquireSameSizeAs(out);
__ Sdiv(temp, dividend, divisor);
__ Msub(out, temp, divisor, dividend);
}
}
}
void LocationsBuilderARM64::VisitDiv(HDiv* div) {
LocationSummary* locations =
new (GetGraph()->GetAllocator()) LocationSummary(div, LocationSummary::kNoCall);
switch (div->GetResultType()) {
case DataType::Type::kInt32:
case DataType::Type::kInt64:
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RegisterOrConstant(div->InputAt(1)));
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
break;
case DataType::Type::kFloat32:
case DataType::Type::kFloat64:
locations->SetInAt(0, Location::RequiresFpuRegister());
locations->SetInAt(1, Location::RequiresFpuRegister());
locations->SetOut(Location::RequiresFpuRegister(), Location::kNoOutputOverlap);
break;
default:
LOG(FATAL) << "Unexpected div type " << div->GetResultType();
}
}
void InstructionCodeGeneratorARM64::VisitDiv(HDiv* div) {
DataType::Type type = div->GetResultType();
switch (type) {
case DataType::Type::kInt32:
case DataType::Type::kInt64:
GenerateDivRemIntegral(div);
break;
case DataType::Type::kFloat32:
case DataType::Type::kFloat64:
__ Fdiv(OutputFPRegister(div), InputFPRegisterAt(div, 0), InputFPRegisterAt(div, 1));
break;
default:
LOG(FATAL) << "Unexpected div type " << type;
}
}
void LocationsBuilderARM64::VisitDivZeroCheck(HDivZeroCheck* instruction) {
LocationSummary* locations = codegen_->CreateThrowingSlowPathLocations(instruction);
locations->SetInAt(0, Location::RegisterOrConstant(instruction->InputAt(0)));
}
void InstructionCodeGeneratorARM64::VisitDivZeroCheck(HDivZeroCheck* instruction) {
SlowPathCodeARM64* slow_path =
new (codegen_->GetScopedAllocator()) DivZeroCheckSlowPathARM64(instruction);
codegen_->AddSlowPath(slow_path);
Location value = instruction->GetLocations()->InAt(0);
DataType::Type type = instruction->GetType();
if (!DataType::IsIntegralType(type)) {
LOG(FATAL) << "Unexpected type " << type << " for DivZeroCheck.";
return;
}
if (value.IsConstant()) {
int64_t divisor = Int64ConstantFrom(value);
if (divisor == 0) {
__ B(slow_path->GetEntryLabel());
} else {
// A division by a non-null constant is valid. We don't need to perform
// any check, so simply fall through.
}
} else {
__ Cbz(InputRegisterAt(instruction, 0), slow_path->GetEntryLabel());
}
}
void LocationsBuilderARM64::VisitDoubleConstant(HDoubleConstant* constant) {
LocationSummary* locations =
new (GetGraph()->GetAllocator()) LocationSummary(constant, LocationSummary::kNoCall);
locations->SetOut(Location::ConstantLocation(constant));
}
void InstructionCodeGeneratorARM64::VisitDoubleConstant(
HDoubleConstant* constant ATTRIBUTE_UNUSED) {
// Will be generated at use site.
}
void LocationsBuilderARM64::VisitExit(HExit* exit) {
exit->SetLocations(nullptr);
}
void InstructionCodeGeneratorARM64::VisitExit(HExit* exit ATTRIBUTE_UNUSED) {
}
void LocationsBuilderARM64::VisitFloatConstant(HFloatConstant* constant) {
LocationSummary* locations =
new (GetGraph()->GetAllocator()) LocationSummary(constant, LocationSummary::kNoCall);
locations->SetOut(Location::ConstantLocation(constant));
}
void InstructionCodeGeneratorARM64::VisitFloatConstant(HFloatConstant* constant ATTRIBUTE_UNUSED) {
// Will be generated at use site.
}
void InstructionCodeGeneratorARM64::HandleGoto(HInstruction* got, HBasicBlock* successor) {
if (successor->IsExitBlock()) {
DCHECK(got->GetPrevious()->AlwaysThrows());
return; // no code needed
}
HBasicBlock* block = got->GetBlock();
HInstruction* previous = got->GetPrevious();
HLoopInformation* info = block->GetLoopInformation();
if (info != nullptr && info->IsBackEdge(*block) && info->HasSuspendCheck()) {
if (codegen_->GetCompilerOptions().CountHotnessInCompiledCode()) {
UseScratchRegisterScope temps(GetVIXLAssembler());
Register temp1 = temps.AcquireX();
Register temp2 = temps.AcquireX();
__ Ldr(temp1, MemOperand(sp, 0));
__ Ldrh(temp2, MemOperand(temp1, ArtMethod::HotnessCountOffset().Int32Value()));
__ Add(temp2, temp2, 1);
__ Strh(temp2, MemOperand(temp1, ArtMethod::HotnessCountOffset().Int32Value()));
}
GenerateSuspendCheck(info->GetSuspendCheck(), successor);
return;
}
if (block->IsEntryBlock() && (previous != nullptr) && previous->IsSuspendCheck()) {
GenerateSuspendCheck(previous->AsSuspendCheck(), nullptr);
codegen_->MaybeGenerateMarkingRegisterCheck(/* code */ __LINE__);
}
if (!codegen_->GoesToNextBlock(block, successor)) {
__ B(codegen_->GetLabelOf(successor));
}
}
void LocationsBuilderARM64::VisitGoto(HGoto* got) {
got->SetLocations(nullptr);
}
void InstructionCodeGeneratorARM64::VisitGoto(HGoto* got) {
HandleGoto(got, got->GetSuccessor());
}
void LocationsBuilderARM64::VisitTryBoundary(HTryBoundary* try_boundary) {
try_boundary->SetLocations(nullptr);
}
void InstructionCodeGeneratorARM64::VisitTryBoundary(HTryBoundary* try_boundary) {
HBasicBlock* successor = try_boundary->GetNormalFlowSuccessor();
if (!successor->IsExitBlock()) {
HandleGoto(try_boundary, successor);
}
}
void InstructionCodeGeneratorARM64::GenerateTestAndBranch(HInstruction* instruction,
size_t condition_input_index,
vixl::aarch64::Label* true_target,
vixl::aarch64::Label* false_target) {
HInstruction* cond = instruction->InputAt(condition_input_index);
if (true_target == nullptr && false_target == nullptr) {
// Nothing to do. The code always falls through.
return;
} else if (cond->IsIntConstant()) {
// Constant condition, statically compared against "true" (integer value 1).
if (cond->AsIntConstant()->IsTrue()) {
if (true_target != nullptr) {
__ B(true_target);
}
} else {
DCHECK(cond->AsIntConstant()->IsFalse()) << cond->AsIntConstant()->GetValue();
if (false_target != nullptr) {
__ B(false_target);
}
}
return;
}
// The following code generates these patterns:
// (1) true_target == nullptr && false_target != nullptr
// - opposite condition true => branch to false_target
// (2) true_target != nullptr && false_target == nullptr
// - condition true => branch to true_target
// (3) true_target != nullptr && false_target != nullptr
// - condition true => branch to true_target
// - branch to false_target
if (IsBooleanValueOrMaterializedCondition(cond)) {
// The condition instruction has been materialized, compare the output to 0.
Location cond_val = instruction->GetLocations()->InAt(condition_input_index);
DCHECK(cond_val.IsRegister());
if (true_target == nullptr) {
__ Cbz(InputRegisterAt(instruction, condition_input_index), false_target);
} else {
__ Cbnz(InputRegisterAt(instruction, condition_input_index), true_target);
}
} else {
// The condition instruction has not been materialized, use its inputs as
// the comparison and its condition as the branch condition.
HCondition* condition = cond->AsCondition();
DataType::Type type = condition->InputAt(0)->GetType();
if (DataType::IsFloatingPointType(type)) {
GenerateFcmp(condition);
if (true_target == nullptr) {
IfCondition opposite_condition = condition->GetOppositeCondition();
__ B(ARM64FPCondition(opposite_condition, condition->IsGtBias()), false_target);
} else {
__ B(ARM64FPCondition(condition->GetCondition(), condition->IsGtBias()), true_target);
}
} else {
// Integer cases.
Register lhs = InputRegisterAt(condition, 0);
Operand rhs = InputOperandAt(condition, 1);
Condition arm64_cond;
vixl::aarch64::Label* non_fallthrough_target;
if (true_target == nullptr) {
arm64_cond = ARM64Condition(condition->GetOppositeCondition());
non_fallthrough_target = false_target;
} else {
arm64_cond = ARM64Condition(condition->GetCondition());
non_fallthrough_target = true_target;
}
if ((arm64_cond == eq || arm64_cond == ne || arm64_cond == lt || arm64_cond == ge) &&
rhs.IsImmediate() && (rhs.GetImmediate() == 0)) {
switch (arm64_cond) {
case eq:
__ Cbz(lhs, non_fallthrough_target);
break;
case ne:
__ Cbnz(lhs, non_fallthrough_target);
break;
case lt:
// Test the sign bit and branch accordingly.
__ Tbnz(lhs, (lhs.IsX() ? kXRegSize : kWRegSize) - 1, non_fallthrough_target);
break;
case ge:
// Test the sign bit and branch accordingly.
__ Tbz(lhs, (lhs.IsX() ? kXRegSize : kWRegSize) - 1, non_fallthrough_target);
break;
default:
// Without the `static_cast` the compiler throws an error for
// `-Werror=sign-promo`.
LOG(FATAL) << "Unexpected condition: " << static_cast<int>(arm64_cond);
}
} else {
__ Cmp(lhs, rhs);
__ B(arm64_cond, non_fallthrough_target);
}
}
}
// If neither branch falls through (case 3), the conditional branch to `true_target`
// was already emitted (case 2) and we need to emit a jump to `false_target`.
if (true_target != nullptr && false_target != nullptr) {
__ B(false_target);
}
}
void LocationsBuilderARM64::VisitIf(HIf* if_instr) {
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(if_instr);
if (IsBooleanValueOrMaterializedCondition(if_instr->InputAt(0))) {
locations->SetInAt(0, Location::RequiresRegister());
}
}
void InstructionCodeGeneratorARM64::VisitIf(HIf* if_instr) {
HBasicBlock* true_successor = if_instr->IfTrueSuccessor();
HBasicBlock* false_successor = if_instr->IfFalseSuccessor();
vixl::aarch64::Label* true_target = codegen_->GetLabelOf(true_successor);
if (codegen_->GoesToNextBlock(if_instr->GetBlock(), true_successor)) {
true_target = nullptr;
}
vixl::aarch64::Label* false_target = codegen_->GetLabelOf(false_successor);
if (codegen_->GoesToNextBlock(if_instr->GetBlock(), false_successor)) {
false_target = nullptr;
}
GenerateTestAndBranch(if_instr, /* condition_input_index */ 0, true_target, false_target);
}
void LocationsBuilderARM64::VisitDeoptimize(HDeoptimize* deoptimize) {
LocationSummary* locations = new (GetGraph()->GetAllocator())
LocationSummary(deoptimize, LocationSummary::kCallOnSlowPath);
InvokeRuntimeCallingConvention calling_convention;
RegisterSet caller_saves = RegisterSet::Empty();
caller_saves.Add(Location::RegisterLocation(calling_convention.GetRegisterAt(0).GetCode()));
locations->SetCustomSlowPathCallerSaves(caller_saves);
if (IsBooleanValueOrMaterializedCondition(deoptimize->InputAt(0))) {
locations->SetInAt(0, Location::RequiresRegister());
}
}
void InstructionCodeGeneratorARM64::VisitDeoptimize(HDeoptimize* deoptimize) {
SlowPathCodeARM64* slow_path =
deopt_slow_paths_.NewSlowPath<DeoptimizationSlowPathARM64>(deoptimize);
GenerateTestAndBranch(deoptimize,
/* condition_input_index */ 0,
slow_path->GetEntryLabel(),
/* false_target */ nullptr);
}
void LocationsBuilderARM64::VisitShouldDeoptimizeFlag(HShouldDeoptimizeFlag* flag) {
LocationSummary* locations = new (GetGraph()->GetAllocator())
LocationSummary(flag, LocationSummary::kNoCall);
locations->SetOut(Location::RequiresRegister());
}
void InstructionCodeGeneratorARM64::VisitShouldDeoptimizeFlag(HShouldDeoptimizeFlag* flag) {
__ Ldr(OutputRegister(flag),
MemOperand(sp, codegen_->GetStackOffsetOfShouldDeoptimizeFlag()));
}
static inline bool IsConditionOnFloatingPointValues(HInstruction* condition) {
return condition->IsCondition() &&
DataType::IsFloatingPointType(condition->InputAt(0)->GetType());
}
static inline Condition GetConditionForSelect(HCondition* condition) {
IfCondition cond = condition->AsCondition()->GetCondition();
return IsConditionOnFloatingPointValues(condition) ? ARM64FPCondition(cond, condition->IsGtBias())
: ARM64Condition(cond);
}
void LocationsBuilderARM64::VisitSelect(HSelect* select) {
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(select);
if (DataType::IsFloatingPointType(select->GetType())) {
locations->SetInAt(0, Location::RequiresFpuRegister());
locations->SetInAt(1, Location::RequiresFpuRegister());
locations->SetOut(Location::RequiresFpuRegister(), Location::kNoOutputOverlap);
} else {
HConstant* cst_true_value = select->GetTrueValue()->AsConstant();
HConstant* cst_false_value = select->GetFalseValue()->AsConstant();
bool is_true_value_constant = cst_true_value != nullptr;
bool is_false_value_constant = cst_false_value != nullptr;
// Ask VIXL whether we should synthesize constants in registers.
// We give an arbitrary register to VIXL when dealing with non-constant inputs.
Operand true_op = is_true_value_constant ?
Operand(Int64FromConstant(cst_true_value)) : Operand(x1);
Operand false_op = is_false_value_constant ?
Operand(Int64FromConstant(cst_false_value)) : Operand(x2);
bool true_value_in_register = false;
bool false_value_in_register = false;
MacroAssembler::GetCselSynthesisInformation(
x0, true_op, false_op, &true_value_in_register, &false_value_in_register);
true_value_in_register |= !is_true_value_constant;
false_value_in_register |= !is_false_value_constant;
locations->SetInAt(1, true_value_in_register ? Location::RequiresRegister()
: Location::ConstantLocation(cst_true_value));
locations->SetInAt(0, false_value_in_register ? Location::RequiresRegister()
: Location::ConstantLocation(cst_false_value));
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
}
if (IsBooleanValueOrMaterializedCondition(select->GetCondition())) {
locations->SetInAt(2, Location::RequiresRegister());
}
}
void InstructionCodeGeneratorARM64::VisitSelect(HSelect* select) {
HInstruction* cond = select->GetCondition();
Condition csel_cond;
if (IsBooleanValueOrMaterializedCondition(cond)) {
if (cond->IsCondition() && cond->GetNext() == select) {
// Use the condition flags set by the previous instruction.
csel_cond = GetConditionForSelect(cond->AsCondition());
} else {
__ Cmp(InputRegisterAt(select, 2), 0);
csel_cond = ne;
}
} else if (IsConditionOnFloatingPointValues(cond)) {
GenerateFcmp(cond);
csel_cond = GetConditionForSelect(cond->AsCondition());
} else {
__ Cmp(InputRegisterAt(cond, 0), InputOperandAt(cond, 1));
csel_cond = GetConditionForSelect(cond->AsCondition());
}
if (DataType::IsFloatingPointType(select->GetType())) {
__ Fcsel(OutputFPRegister(select),
InputFPRegisterAt(select, 1),
InputFPRegisterAt(select, 0),
csel_cond);
} else {
__ Csel(OutputRegister(select),
InputOperandAt(select, 1),
InputOperandAt(select, 0),
csel_cond);
}
}
void LocationsBuilderARM64::VisitNativeDebugInfo(HNativeDebugInfo* info) {
new (GetGraph()->GetAllocator()) LocationSummary(info);
}
void InstructionCodeGeneratorARM64::VisitNativeDebugInfo(HNativeDebugInfo*) {
// MaybeRecordNativeDebugInfo is already called implicitly in CodeGenerator::Compile.
}
void CodeGeneratorARM64::GenerateNop() {
__ Nop();
}
void LocationsBuilderARM64::VisitInstanceFieldGet(HInstanceFieldGet* instruction) {
HandleFieldGet(instruction, instruction->GetFieldInfo());
}
void InstructionCodeGeneratorARM64::VisitInstanceFieldGet(HInstanceFieldGet* instruction) {
HandleFieldGet(instruction, instruction->GetFieldInfo());
}
void LocationsBuilderARM64::VisitInstanceFieldSet(HInstanceFieldSet* instruction) {
HandleFieldSet(instruction);
}
void InstructionCodeGeneratorARM64::VisitInstanceFieldSet(HInstanceFieldSet* instruction) {
HandleFieldSet(instruction, instruction->GetFieldInfo(), instruction->GetValueCanBeNull());
}
// Temp is used for read barrier.
static size_t NumberOfInstanceOfTemps(TypeCheckKind type_check_kind) {
if (kEmitCompilerReadBarrier &&
(kUseBakerReadBarrier ||
type_check_kind == TypeCheckKind::kAbstractClassCheck ||
type_check_kind == TypeCheckKind::kClassHierarchyCheck ||
type_check_kind == TypeCheckKind::kArrayObjectCheck)) {
return 1;
}
return 0;
}
// Interface case has 3 temps, one for holding the number of interfaces, one for the current
// interface pointer, one for loading the current interface.
// The other checks have one temp for loading the object's class.
static size_t NumberOfCheckCastTemps(TypeCheckKind type_check_kind) {
if (type_check_kind == TypeCheckKind::kInterfaceCheck) {
return 3;
}
return 1 + NumberOfInstanceOfTemps(type_check_kind);
}
void LocationsBuilderARM64::VisitInstanceOf(HInstanceOf* instruction) {
LocationSummary::CallKind call_kind = LocationSummary::kNoCall;
TypeCheckKind type_check_kind = instruction->GetTypeCheckKind();
bool baker_read_barrier_slow_path = false;
switch (type_check_kind) {
case TypeCheckKind::kExactCheck:
case TypeCheckKind::kAbstractClassCheck:
case TypeCheckKind::kClassHierarchyCheck:
case TypeCheckKind::kArrayObjectCheck: {
bool needs_read_barrier = CodeGenerator::InstanceOfNeedsReadBarrier(instruction);
call_kind = needs_read_barrier ? LocationSummary::kCallOnSlowPath : LocationSummary::kNoCall;
baker_read_barrier_slow_path = kUseBakerReadBarrier && needs_read_barrier;
break;
}
case TypeCheckKind::kArrayCheck:
case TypeCheckKind::kUnresolvedCheck:
case TypeCheckKind::kInterfaceCheck:
call_kind = LocationSummary::kCallOnSlowPath;
break;
case TypeCheckKind::kBitstringCheck:
break;
}
LocationSummary* locations =
new (GetGraph()->GetAllocator()) LocationSummary(instruction, call_kind);
if (baker_read_barrier_slow_path) {
locations->SetCustomSlowPathCallerSaves(RegisterSet::Empty()); // No caller-save registers.
}
locations->SetInAt(0, Location::RequiresRegister());
if (type_check_kind == TypeCheckKind::kBitstringCheck) {
locations->SetInAt(1, Location::ConstantLocation(instruction->InputAt(1)->AsConstant()));
locations->SetInAt(2, Location::ConstantLocation(instruction->InputAt(2)->AsConstant()));
locations->SetInAt(3, Location::ConstantLocation(instruction->InputAt(3)->AsConstant()));
} else {
locations->SetInAt(1, Location::RequiresRegister());
}
// The "out" register is used as a temporary, so it overlaps with the inputs.
// Note that TypeCheckSlowPathARM64 uses this register too.
locations->SetOut(Location::RequiresRegister(), Location::kOutputOverlap);
// Add temps if necessary for read barriers.
locations->AddRegisterTemps(NumberOfInstanceOfTemps(type_check_kind));
}
void InstructionCodeGeneratorARM64::VisitInstanceOf(HInstanceOf* instruction) {
TypeCheckKind type_check_kind = instruction->GetTypeCheckKind();
LocationSummary* locations = instruction->GetLocations();
Location obj_loc = locations->InAt(0);
Register obj = InputRegisterAt(instruction, 0);
Register cls = (type_check_kind == TypeCheckKind::kBitstringCheck)
? Register()
: InputRegisterAt(instruction, 1);
Location out_loc = locations->Out();
Register out = OutputRegister(instruction);
const size_t num_temps = NumberOfInstanceOfTemps(type_check_kind);
DCHECK_LE(num_temps, 1u);
Location maybe_temp_loc = (num_temps >= 1) ? locations->GetTemp(0) : Location::NoLocation();
uint32_t class_offset = mirror::Object::ClassOffset().Int32Value();
uint32_t super_offset = mirror::Class::SuperClassOffset().Int32Value();
uint32_t component_offset = mirror::Class::ComponentTypeOffset().Int32Value();
uint32_t primitive_offset = mirror::Class::PrimitiveTypeOffset().Int32Value();
vixl::aarch64::Label done, zero;
SlowPathCodeARM64* slow_path = nullptr;
// Return 0 if `obj` is null.
// Avoid null check if we know `obj` is not null.
if (instruction->MustDoNullCheck()) {
__ Cbz(obj, &zero);
}
switch (type_check_kind) {
case TypeCheckKind::kExactCheck: {
ReadBarrierOption read_barrier_option =
CodeGenerator::ReadBarrierOptionForInstanceOf(instruction);
// /* HeapReference<Class> */ out = obj->klass_
GenerateReferenceLoadTwoRegisters(instruction,
out_loc,
obj_loc,
class_offset,
maybe_temp_loc,
read_barrier_option);
__ Cmp(out, cls);
__ Cset(out, eq);
if (zero.IsLinked()) {
__ B(&done);
}
break;
}
case TypeCheckKind::kAbstractClassCheck: {
ReadBarrierOption read_barrier_option =
CodeGenerator::ReadBarrierOptionForInstanceOf(instruction);
// /* HeapReference<Class> */ out = obj->klass_
GenerateReferenceLoadTwoRegisters(instruction,
out_loc,
obj_loc,
class_offset,
maybe_temp_loc,
read_barrier_option);
// If the class is abstract, we eagerly fetch the super class of the
// object to avoid doing a comparison we know will fail.
vixl::aarch64::Label loop, success;
__ Bind(&loop);
// /* HeapReference<Class> */ out = out->super_class_
GenerateReferenceLoadOneRegister(instruction,
out_loc,
super_offset,
maybe_temp_loc,
read_barrier_option);
// If `out` is null, we use it for the result, and jump to `done`.
__ Cbz(out, &done);
__ Cmp(out, cls);
__ B(ne, &loop);
__ Mov(out, 1);
if (zero.IsLinked()) {
__ B(&done);
}
break;
}
case TypeCheckKind::kClassHierarchyCheck: {
ReadBarrierOption read_barrier_option =
CodeGenerator::ReadBarrierOptionForInstanceOf(instruction);
// /* HeapReference<Class> */ out = obj->klass_
GenerateReferenceLoadTwoRegisters(instruction,
out_loc,
obj_loc,
class_offset,
maybe_temp_loc,
read_barrier_option);
// Walk over the class hierarchy to find a match.
vixl::aarch64::Label loop, success;
__ Bind(&loop);
__ Cmp(out, cls);
__ B(eq, &success);
// /* HeapReference<Class> */ out = out->super_class_
GenerateReferenceLoadOneRegister(instruction,
out_loc,
super_offset,
maybe_temp_loc,
read_barrier_option);
__ Cbnz(out, &loop);
// If `out` is null, we use it for the result, and jump to `done`.
__ B(&done);
__ Bind(&success);
__ Mov(out, 1);
if (zero.IsLinked()) {
__ B(&done);
}
break;
}
case TypeCheckKind::kArrayObjectCheck: {
ReadBarrierOption read_barrier_option =
CodeGenerator::ReadBarrierOptionForInstanceOf(instruction);
// /* HeapReference<Class> */ out = obj->klass_
GenerateReferenceLoadTwoRegisters(instruction,
out_loc,
obj_loc,
class_offset,
maybe_temp_loc,
read_barrier_option);
// Do an exact check.
vixl::aarch64::Label exact_check;
__ Cmp(out, cls);
__ B(eq, &exact_check);
// Otherwise, we need to check that the object's class is a non-primitive array.
// /* HeapReference<Class> */ out = out->component_type_
GenerateReferenceLoadOneRegister(instruction,
out_loc,
component_offset,
maybe_temp_loc,
read_barrier_option);
// If `out` is null, we use it for the result, and jump to `done`.
__ Cbz(out, &done);
__ Ldrh(out, HeapOperand(out, primitive_offset));
static_assert(Primitive::kPrimNot == 0, "Expected 0 for kPrimNot");
__ Cbnz(out, &zero);
__ Bind(&exact_check);
__ Mov(out, 1);
__ B(&done);
break;
}
case TypeCheckKind::kArrayCheck: {
// No read barrier since the slow path will retry upon failure.
// /* HeapReference<Class> */ out = obj->klass_
GenerateReferenceLoadTwoRegisters(instruction,
out_loc,
obj_loc,
class_offset,
maybe_temp_loc,
kWithoutReadBarrier);
__ Cmp(out, cls);
DCHECK(locations->OnlyCallsOnSlowPath());
slow_path = new (codegen_->GetScopedAllocator()) TypeCheckSlowPathARM64(
instruction, /* is_fatal */ false);
codegen_->AddSlowPath(slow_path);
__ B(ne, slow_path->GetEntryLabel());
__ Mov(out, 1);
if (zero.IsLinked()) {
__ B(&done);
}
break;
}
case TypeCheckKind::kUnresolvedCheck:
case TypeCheckKind::kInterfaceCheck: {
// Note that we indeed only call on slow path, but we always go
// into the slow path for the unresolved and interface check
// cases.
//
// We cannot directly call the InstanceofNonTrivial runtime
// entry point without resorting to a type checking slow path
// here (i.e. by calling InvokeRuntime directly), as it would
// require to assign fixed registers for the inputs of this
// HInstanceOf instruction (following the runtime calling
// convention), which might be cluttered by the potential first
// read barrier emission at the beginning of this method.
//
// TODO: Introduce a new runtime entry point taking the object
// to test (instead of its class) as argument, and let it deal
// with the read barrier issues. This will let us refactor this
// case of the `switch` code as it was previously (with a direct
// call to the runtime not using a type checking slow path).
// This should also be beneficial for the other cases above.
DCHECK(locations->OnlyCallsOnSlowPath());
slow_path = new (codegen_->GetScopedAllocator()) TypeCheckSlowPathARM64(
instruction, /* is_fatal */ false);
codegen_->AddSlowPath(slow_path);
__ B(slow_path->GetEntryLabel());
if (zero.IsLinked()) {
__ B(&done);
}
break;
}
case TypeCheckKind::kBitstringCheck: {
// /* HeapReference<Class> */ temp = obj->klass_
GenerateReferenceLoadTwoRegisters(instruction,
out_loc,
obj_loc,
class_offset,
maybe_temp_loc,
kWithoutReadBarrier);
GenerateBitstringTypeCheckCompare(instruction, out);
__ Cset(out, eq);
if (zero.IsLinked()) {
__ B(&done);
}
break;
}
}
if (zero.IsLinked()) {
__ Bind(&zero);
__ Mov(out, 0);
}
if (done.IsLinked()) {
__ Bind(&done);
}
if (slow_path != nullptr) {
__ Bind(slow_path->GetExitLabel());
}
}
void LocationsBuilderARM64::VisitCheckCast(HCheckCast* instruction) {
TypeCheckKind type_check_kind = instruction->GetTypeCheckKind();
LocationSummary::CallKind call_kind = CodeGenerator::GetCheckCastCallKind(instruction);
LocationSummary* locations =
new (GetGraph()->GetAllocator()) LocationSummary(instruction, call_kind);
locations->SetInAt(0, Location::RequiresRegister());
if (type_check_kind == TypeCheckKind::kBitstringCheck) {
locations->SetInAt(1, Location::ConstantLocation(instruction->InputAt(1)->AsConstant()));
locations->SetInAt(2, Location::ConstantLocation(instruction->InputAt(2)->AsConstant()));
locations->SetInAt(3, Location::ConstantLocation(instruction->InputAt(3)->AsConstant()));
} else {
locations->SetInAt(1, Location::RequiresRegister());
}
// Add temps for read barriers and other uses. One is used by TypeCheckSlowPathARM64.
locations->AddRegisterTemps(NumberOfCheckCastTemps(type_check_kind));
}
void InstructionCodeGeneratorARM64::VisitCheckCast(HCheckCast* instruction) {
TypeCheckKind type_check_kind = instruction->GetTypeCheckKind();
LocationSummary* locations = instruction->GetLocations();
Location obj_loc = locations->InAt(0);
Register obj = InputRegisterAt(instruction, 0);
Register cls = (type_check_kind == TypeCheckKind::kBitstringCheck)
? Register()
: InputRegisterAt(instruction, 1);
const size_t num_temps = NumberOfCheckCastTemps(type_check_kind);
DCHECK_GE(num_temps, 1u);
DCHECK_LE(num_temps, 3u);
Location temp_loc = locations->GetTemp(0);
Location maybe_temp2_loc = (num_temps >= 2) ? locations->GetTemp(1) : Location::NoLocation();
Location maybe_temp3_loc = (num_temps >= 3) ? locations->GetTemp(2) : Location::NoLocation();
Register temp = WRegisterFrom(temp_loc);
const uint32_t class_offset = mirror::Object::ClassOffset().Int32Value();
const uint32_t super_offset = mirror::Class::SuperClassOffset().Int32Value();
const uint32_t component_offset = mirror::Class::ComponentTypeOffset().Int32Value();
const uint32_t primitive_offset = mirror::Class::PrimitiveTypeOffset().Int32Value();
const uint32_t iftable_offset = mirror::Class::IfTableOffset().Uint32Value();
const uint32_t array_length_offset = mirror::Array::LengthOffset().Uint32Value();
const uint32_t object_array_data_offset =
mirror::Array::DataOffset(kHeapReferenceSize).Uint32Value();
bool is_type_check_slow_path_fatal = CodeGenerator::IsTypeCheckSlowPathFatal(instruction);
SlowPathCodeARM64* type_check_slow_path =
new (codegen_->GetScopedAllocator()) TypeCheckSlowPathARM64(
instruction, is_type_check_slow_path_fatal);
codegen_->AddSlowPath(type_check_slow_path);
vixl::aarch64::Label done;
// Avoid null check if we know obj is not null.
if (instruction->MustDoNullCheck()) {
__ Cbz(obj, &done);
}
switch (type_check_kind) {
case TypeCheckKind::kExactCheck:
case TypeCheckKind::kArrayCheck: {
// /* HeapReference<Class> */ temp = obj->klass_
GenerateReferenceLoadTwoRegisters(instruction,
temp_loc,
obj_loc,
class_offset,
maybe_temp2_loc,
kWithoutReadBarrier);
__ Cmp(temp, cls);
// Jump to slow path for throwing the exception or doing a
// more involved array check.
__ B(ne, type_check_slow_path->GetEntryLabel());
break;
}
case TypeCheckKind::kAbstractClassCheck: {
// /* HeapReference<Class> */ temp = obj->klass_
GenerateReferenceLoadTwoRegisters(instruction,
temp_loc,
obj_loc,
class_offset,
maybe_temp2_loc,
kWithoutReadBarrier);
// If the class is abstract, we eagerly fetch the super class of the
// object to avoid doing a comparison we know will fail.
vixl::aarch64::Label loop;
__ Bind(&loop);
// /* HeapReference<Class> */ temp = temp->super_class_
GenerateReferenceLoadOneRegister(instruction,
temp_loc,
super_offset,
maybe_temp2_loc,
kWithoutReadBarrier);
// If the class reference currently in `temp` is null, jump to the slow path to throw the
// exception.
__ Cbz(temp, type_check_slow_path->GetEntryLabel());
// Otherwise, compare classes.
__ Cmp(temp, cls);
__ B(ne, &loop);
break;
}
case TypeCheckKind::kClassHierarchyCheck: {
// /* HeapReference<Class> */ temp = obj->klass_
GenerateReferenceLoadTwoRegisters(instruction,
temp_loc,
obj_loc,
class_offset,
maybe_temp2_loc,
kWithoutReadBarrier);
// Walk over the class hierarchy to find a match.
vixl::aarch64::Label loop;
__ Bind(&loop);
__ Cmp(temp, cls);
__ B(eq, &done);
// /* HeapReference<Class> */ temp = temp->super_class_
GenerateReferenceLoadOneRegister(instruction,
temp_loc,
super_offset,
maybe_temp2_loc,
kWithoutReadBarrier);
// If the class reference currently in `temp` is not null, jump
// back at the beginning of the loop.
__ Cbnz(temp, &loop);
// Otherwise, jump to the slow path to throw the exception.
__ B(type_check_slow_path->GetEntryLabel());
break;
}
case TypeCheckKind::kArrayObjectCheck: {
// /* HeapReference<Class> */ temp = obj->klass_
GenerateReferenceLoadTwoRegisters(instruction,
temp_loc,
obj_loc,
class_offset,
maybe_temp2_loc,
kWithoutReadBarrier);
// Do an exact check.
__ Cmp(temp, cls);
__ B(eq, &done);
// Otherwise, we need to check that the object's class is a non-primitive array.
// /* HeapReference<Class> */ temp = temp->component_type_
GenerateReferenceLoadOneRegister(instruction,
temp_loc,
component_offset,
maybe_temp2_loc,
kWithoutReadBarrier);
// If the component type is null, jump to the slow path to throw the exception.
__ Cbz(temp, type_check_slow_path->GetEntryLabel());
// Otherwise, the object is indeed an array. Further check that this component type is not a
// primitive type.
__ Ldrh(temp, HeapOperand(temp, primitive_offset));
static_assert(Primitive::kPrimNot == 0, "Expected 0 for kPrimNot");
__ Cbnz(temp, type_check_slow_path->GetEntryLabel());
break;
}
case TypeCheckKind::kUnresolvedCheck:
// We always go into the type check slow path for the unresolved check cases.
//
// We cannot directly call the CheckCast runtime entry point
// without resorting to a type checking slow path here (i.e. by
// calling InvokeRuntime directly), as it would require to
// assign fixed registers for the inputs of this HInstanceOf
// instruction (following the runtime calling convention), which
// might be cluttered by the potential first read barrier
// emission at the beginning of this method.
__ B(type_check_slow_path->GetEntryLabel());
break;
case TypeCheckKind::kInterfaceCheck: {
// /* HeapReference<Class> */ temp = obj->klass_
GenerateReferenceLoadTwoRegisters(instruction,
temp_loc,
obj_loc,
class_offset,
maybe_temp2_loc,
kWithoutReadBarrier);
// /* HeapReference<Class> */ temp = temp->iftable_
GenerateReferenceLoadTwoRegisters(instruction,
temp_loc,
temp_loc,
iftable_offset,
maybe_temp2_loc,
kWithoutReadBarrier);
// Iftable is never null.
__ Ldr(WRegisterFrom(maybe_temp2_loc), HeapOperand(temp.W(), array_length_offset));
// Loop through the iftable and check if any class matches.
vixl::aarch64::Label start_loop;
__ Bind(&start_loop);
__ Cbz(WRegisterFrom(maybe_temp2_loc), type_check_slow_path->GetEntryLabel());
__ Ldr(WRegisterFrom(maybe_temp3_loc), HeapOperand(temp.W(), object_array_data_offset));
GetAssembler()->MaybeUnpoisonHeapReference(WRegisterFrom(maybe_temp3_loc));
// Go to next interface.
__ Add(temp, temp, 2 * kHeapReferenceSize);
__ Sub(WRegisterFrom(maybe_temp2_loc), WRegisterFrom(maybe_temp2_loc), 2);
// Compare the classes and continue the loop if they do not match.
__ Cmp(cls, WRegisterFrom(maybe_temp3_loc));
__ B(ne, &start_loop);
break;
}
case TypeCheckKind::kBitstringCheck: {
// /* HeapReference<Class> */ temp = obj->klass_
GenerateReferenceLoadTwoRegisters(instruction,
temp_loc,
obj_loc,
class_offset,
maybe_temp2_loc,
kWithoutReadBarrier);
GenerateBitstringTypeCheckCompare(instruction, temp);
__ B(ne, type_check_slow_path->GetEntryLabel());
break;
}
}
__ Bind(&done);
__ Bind(type_check_slow_path->GetExitLabel());
}
void LocationsBuilderARM64::VisitIntConstant(HIntConstant* constant) {
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(constant);
locations->SetOut(Location::ConstantLocation(constant));
}
void InstructionCodeGeneratorARM64::VisitIntConstant(HIntConstant* constant ATTRIBUTE_UNUSED) {
// Will be generated at use site.
}
void LocationsBuilderARM64::VisitNullConstant(HNullConstant* constant) {
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(constant);
locations->SetOut(Location::ConstantLocation(constant));
}
void InstructionCodeGeneratorARM64::VisitNullConstant(HNullConstant* constant ATTRIBUTE_UNUSED) {
// Will be generated at use site.
}
void LocationsBuilderARM64::VisitInvokeUnresolved(HInvokeUnresolved* invoke) {
// The trampoline uses the same calling convention as dex calling conventions,
// except instead of loading arg0/r0 with the target Method*, arg0/r0 will contain
// the method_idx.
HandleInvoke(invoke);
}
void InstructionCodeGeneratorARM64::VisitInvokeUnresolved(HInvokeUnresolved* invoke) {
codegen_->GenerateInvokeUnresolvedRuntimeCall(invoke);
codegen_->MaybeGenerateMarkingRegisterCheck(/* code */ __LINE__);
}
void LocationsBuilderARM64::HandleInvoke(HInvoke* invoke) {
InvokeDexCallingConventionVisitorARM64 calling_convention_visitor;
CodeGenerator::CreateCommonInvokeLocationSummary(invoke, &calling_convention_visitor);
}
void LocationsBuilderARM64::VisitInvokeInterface(HInvokeInterface* invoke) {
HandleInvoke(invoke);
}
void InstructionCodeGeneratorARM64::VisitInvokeInterface(HInvokeInterface* invoke) {
// TODO: b/18116999, our IMTs can miss an IncompatibleClassChangeError.
LocationSummary* locations = invoke->GetLocations();
Register temp = XRegisterFrom(locations->GetTemp(0));
Location receiver = locations->InAt(0);
Offset class_offset = mirror::Object::ClassOffset();
Offset entry_point = ArtMethod::EntryPointFromQuickCompiledCodeOffset(kArm64PointerSize);
// The register ip1 is required to be used for the hidden argument in
// art_quick_imt_conflict_trampoline, so prevent VIXL from using it.
MacroAssembler* masm = GetVIXLAssembler();
UseScratchRegisterScope scratch_scope(masm);
scratch_scope.Exclude(ip1);
__ Mov(ip1, invoke->GetDexMethodIndex());
// Ensure that between load and MaybeRecordImplicitNullCheck there are no pools emitted.
if (receiver.IsStackSlot()) {
__ Ldr(temp.W(), StackOperandFrom(receiver));
{
EmissionCheckScope guard(GetVIXLAssembler(), kMaxMacroInstructionSizeInBytes);
// /* HeapReference<Class> */ temp = temp->klass_
__ Ldr(temp.W(), HeapOperand(temp.W(), class_offset));
codegen_->MaybeRecordImplicitNullCheck(invoke);
}
} else {
EmissionCheckScope guard(GetVIXLAssembler(), kMaxMacroInstructionSizeInBytes);
// /* HeapReference<Class> */ temp = receiver->klass_
__ Ldr(temp.W(), HeapOperandFrom(receiver, class_offset));
codegen_->MaybeRecordImplicitNullCheck(invoke);
}
// Instead of simply (possibly) unpoisoning `temp` here, we should
// emit a read barrier for the previous class reference load.
// However this is not required in practice, as this is an
// intermediate/temporary reference and because the current
// concurrent copying collector keeps the from-space memory
// intact/accessible until the end of the marking phase (the
// concurrent copying collector may not in the future).
GetAssembler()->MaybeUnpoisonHeapReference(temp.W());
__ Ldr(temp,
MemOperand(temp, mirror::Class::ImtPtrOffset(kArm64PointerSize).Uint32Value()));
uint32_t method_offset = static_cast<uint32_t>(ImTable::OffsetOfElement(
invoke->GetImtIndex(), kArm64PointerSize));
// temp = temp->GetImtEntryAt(method_offset);
__ Ldr(temp, MemOperand(temp, method_offset));
// lr = temp->GetEntryPoint();
__ Ldr(lr, MemOperand(temp, entry_point.Int32Value()));
{
// Ensure the pc position is recorded immediately after the `blr` instruction.
ExactAssemblyScope eas(GetVIXLAssembler(), kInstructionSize, CodeBufferCheckScope::kExactSize);
// lr();
__ blr(lr);
DCHECK(!codegen_->IsLeafMethod());
codegen_->RecordPcInfo(invoke, invoke->GetDexPc());
}
codegen_->MaybeGenerateMarkingRegisterCheck(/* code */ __LINE__);
}
void LocationsBuilderARM64::VisitInvokeVirtual(HInvokeVirtual* invoke) {
IntrinsicLocationsBuilderARM64 intrinsic(GetGraph()->GetAllocator(), codegen_);
if (intrinsic.TryDispatch(invoke)) {
return;
}
HandleInvoke(invoke);
}
void LocationsBuilderARM64::VisitInvokeStaticOrDirect(HInvokeStaticOrDirect* invoke) {
// Explicit clinit checks triggered by static invokes must have been pruned by
// art::PrepareForRegisterAllocation.
DCHECK(!invoke->IsStaticWithExplicitClinitCheck());
IntrinsicLocationsBuilderARM64 intrinsic(GetGraph()->GetAllocator(), codegen_);
if (intrinsic.TryDispatch(invoke)) {
return;
}
HandleInvoke(invoke);
}
static bool TryGenerateIntrinsicCode(HInvoke* invoke, CodeGeneratorARM64* codegen) {
if (invoke->GetLocations()->Intrinsified()) {
IntrinsicCodeGeneratorARM64 intrinsic(codegen);
intrinsic.Dispatch(invoke);
return true;
}
return false;
}
HInvokeStaticOrDirect::DispatchInfo CodeGeneratorARM64::GetSupportedInvokeStaticOrDirectDispatch(
const HInvokeStaticOrDirect::DispatchInfo& desired_dispatch_info,
HInvokeStaticOrDirect* invoke ATTRIBUTE_UNUSED) {
// On ARM64 we support all dispatch types.
return desired_dispatch_info;
}
void CodeGeneratorARM64::GenerateStaticOrDirectCall(
HInvokeStaticOrDirect* invoke, Location temp, SlowPathCode* slow_path) {
// Make sure that ArtMethod* is passed in kArtMethodRegister as per the calling convention.
Location callee_method = temp; // For all kinds except kRecursive, callee will be in temp.
switch (invoke->GetMethodLoadKind()) {
case HInvokeStaticOrDirect::MethodLoadKind::kStringInit: {
uint32_t offset =
GetThreadOffset<kArm64PointerSize>(invoke->GetStringInitEntryPoint()).Int32Value();
// temp = thread->string_init_entrypoint
__ Ldr(XRegisterFrom(temp), MemOperand(tr, offset));
break;
}
case HInvokeStaticOrDirect::MethodLoadKind::kRecursive:
callee_method = invoke->GetLocations()->InAt(invoke->GetSpecialInputIndex());
break;
case HInvokeStaticOrDirect::MethodLoadKind::kBootImageLinkTimePcRelative: {
DCHECK(GetCompilerOptions().IsBootImage());
// Add ADRP with its PC-relative method patch.
vixl::aarch64::Label* adrp_label = NewBootImageMethodPatch(invoke->GetTargetMethod());
EmitAdrpPlaceholder(adrp_label, XRegisterFrom(temp));
// Add ADD with its PC-relative method patch.
vixl::aarch64::Label* add_label =
NewBootImageMethodPatch(invoke->GetTargetMethod(), adrp_label);
EmitAddPlaceholder(add_label, XRegisterFrom(temp), XRegisterFrom(temp));
break;
}
case HInvokeStaticOrDirect::MethodLoadKind::kDirectAddress:
// Load method address from literal pool.
__ Ldr(XRegisterFrom(temp), DeduplicateUint64Literal(invoke->GetMethodAddress()));
break;
case HInvokeStaticOrDirect::MethodLoadKind::kBootImageRelRo: {
// Add ADRP with its PC-relative .data.bimg.rel.ro patch.
uint32_t boot_image_offset = GetBootImageOffset(invoke);
vixl::aarch64::Label* adrp_label = NewBootImageRelRoPatch(boot_image_offset);
EmitAdrpPlaceholder(adrp_label, XRegisterFrom(temp));
// Add LDR with its PC-relative .data.bimg.rel.ro patch.
vixl::aarch64::Label* ldr_label = NewBootImageRelRoPatch(boot_image_offset, adrp_label);
// Note: Boot image is in the low 4GiB and the entry is 32-bit, so emit a 32-bit load.
EmitLdrOffsetPlaceholder(ldr_label, WRegisterFrom(temp), XRegisterFrom(temp));
break;
}
case HInvokeStaticOrDirect::MethodLoadKind::kBssEntry: {
// Add ADRP with its PC-relative .bss entry patch.
MethodReference target_method(&GetGraph()->GetDexFile(), invoke->GetDexMethodIndex());
vixl::aarch64::Label* adrp_label = NewMethodBssEntryPatch(target_method);
EmitAdrpPlaceholder(adrp_label, XRegisterFrom(temp));
// Add LDR with its PC-relative .bss entry patch.
vixl::aarch64::Label* ldr_label =
NewMethodBssEntryPatch(target_method, adrp_label);
EmitLdrOffsetPlaceholder(ldr_label, XRegisterFrom(temp), XRegisterFrom(temp));
break;
}
case HInvokeStaticOrDirect::MethodLoadKind::kRuntimeCall: {
GenerateInvokeStaticOrDirectRuntimeCall(invoke, temp, slow_path);
return; // No code pointer retrieval; the runtime performs the call directly.
}
}
switch (invoke->GetCodePtrLocation()) {
case HInvokeStaticOrDirect::CodePtrLocation::kCallSelf:
{
// Use a scope to help guarantee that `RecordPcInfo()` records the correct pc.
ExactAssemblyScope eas(GetVIXLAssembler(),
kInstructionSize,
CodeBufferCheckScope::kExactSize);
__ bl(&frame_entry_label_);
RecordPcInfo(invoke, invoke->GetDexPc(), slow_path);
}
break;
case HInvokeStaticOrDirect::CodePtrLocation::kCallArtMethod:
// LR = callee_method->entry_point_from_quick_compiled_code_;
__ Ldr(lr, MemOperand(
XRegisterFrom(callee_method),
ArtMethod::EntryPointFromQuickCompiledCodeOffset(kArm64PointerSize).Int32Value()));
{
// Use a scope to help guarantee that `RecordPcInfo()` records the correct pc.
ExactAssemblyScope eas(GetVIXLAssembler(),
kInstructionSize,
CodeBufferCheckScope::kExactSize);
// lr()
__ blr(lr);
RecordPcInfo(invoke, invoke->GetDexPc(), slow_path);
}
break;
}
DCHECK(!IsLeafMethod());
}
void CodeGeneratorARM64::GenerateVirtualCall(
HInvokeVirtual* invoke, Location temp_in, SlowPathCode* slow_path) {
// Use the calling convention instead of the location of the receiver, as
// intrinsics may have put the receiver in a different register. In the intrinsics
// slow path, the arguments have been moved to the right place, so here we are
// guaranteed that the receiver is the first register of the calling convention.
InvokeDexCallingConvention calling_convention;
Register receiver = calling_convention.GetRegisterAt(0);
Register temp = XRegisterFrom(temp_in);
size_t method_offset = mirror::Class::EmbeddedVTableEntryOffset(
invoke->GetVTableIndex(), kArm64PointerSize).SizeValue();
Offset class_offset = mirror::Object::ClassOffset();
Offset entry_point = ArtMethod::EntryPointFromQuickCompiledCodeOffset(kArm64PointerSize);
DCHECK(receiver.IsRegister());
{
// Ensure that between load and MaybeRecordImplicitNullCheck there are no pools emitted.
EmissionCheckScope guard(GetVIXLAssembler(), kMaxMacroInstructionSizeInBytes);
// /* HeapReference<Class> */ temp = receiver->klass_
__ Ldr(temp.W(), HeapOperandFrom(LocationFrom(receiver), class_offset));
MaybeRecordImplicitNullCheck(invoke);
}
// Instead of simply (possibly) unpoisoning `temp` here, we should
// emit a read barrier for the previous class reference load.
// intermediate/temporary reference and because the current
// concurrent copying collector keeps the from-space memory
// intact/accessible until the end of the marking phase (the
// concurrent copying collector may not in the future).
GetAssembler()->MaybeUnpoisonHeapReference(temp.W());
// temp = temp->GetMethodAt(method_offset);
__ Ldr(temp, MemOperand(temp, method_offset));
// lr = temp->GetEntryPoint();
__ Ldr(lr, MemOperand(temp, entry_point.SizeValue()));
{
// Use a scope to help guarantee that `RecordPcInfo()` records the correct pc.
ExactAssemblyScope eas(GetVIXLAssembler(), kInstructionSize, CodeBufferCheckScope::kExactSize);
// lr();
__ blr(lr);
RecordPcInfo(invoke, invoke->GetDexPc(), slow_path);
}
}
void LocationsBuilderARM64::VisitInvokePolymorphic(HInvokePolymorphic* invoke) {
HandleInvoke(invoke);
}
void InstructionCodeGeneratorARM64::VisitInvokePolymorphic(HInvokePolymorphic* invoke) {
codegen_->GenerateInvokePolymorphicCall(invoke);
codegen_->MaybeGenerateMarkingRegisterCheck(/* code */ __LINE__);
}
vixl::aarch64::Label* CodeGeneratorARM64::NewBootImageRelRoPatch(
uint32_t boot_image_offset,
vixl::aarch64::Label* adrp_label) {
return NewPcRelativePatch(
/* dex_file */ nullptr, boot_image_offset, adrp_label, &boot_image_method_patches_);
}
vixl::aarch64::Label* CodeGeneratorARM64::NewBootImageMethodPatch(
MethodReference target_method,
vixl::aarch64::Label* adrp_label) {
return NewPcRelativePatch(
target_method.dex_file, target_method.index, adrp_label, &boot_image_method_patches_);
}
vixl::aarch64::Label* CodeGeneratorARM64::NewMethodBssEntryPatch(
MethodReference target_method,
vixl::aarch64::Label* adrp_label) {
return NewPcRelativePatch(
target_method.dex_file, target_method.index, adrp_label, &method_bss_entry_patches_);
}
vixl::aarch64::Label* CodeGeneratorARM64::NewBootImageTypePatch(
const DexFile& dex_file,
dex::TypeIndex type_index,
vixl::aarch64::Label* adrp_label) {
return NewPcRelativePatch(&dex_file, type_index.index_, adrp_label, &boot_image_type_patches_);
}
vixl::aarch64::Label* CodeGeneratorARM64::NewBssEntryTypePatch(
const DexFile& dex_file,
dex::TypeIndex type_index,
vixl::aarch64::Label* adrp_label) {
return NewPcRelativePatch(&dex_file, type_index.index_, adrp_label, &type_bss_entry_patches_);
}
vixl::aarch64::Label* CodeGeneratorARM64::NewBootImageStringPatch(
const DexFile& dex_file,
dex::StringIndex string_index,
vixl::aarch64::Label* adrp_label) {
return NewPcRelativePatch(
&dex_file, string_index.index_, adrp_label, &boot_image_string_patches_);
}
vixl::aarch64::Label* CodeGeneratorARM64::NewStringBssEntryPatch(
const DexFile& dex_file,
dex::StringIndex string_index,
vixl::aarch64::Label* adrp_label) {
return NewPcRelativePatch(&dex_file, string_index.index_, adrp_label, &string_bss_entry_patches_);
}
vixl::aarch64::Label* CodeGeneratorARM64::NewBakerReadBarrierPatch(uint32_t custom_data) {
baker_read_barrier_patches_.emplace_back(custom_data);
return &baker_read_barrier_patches_.back().label;
}
vixl::aarch64::Label* CodeGeneratorARM64::NewPcRelativePatch(
const DexFile* dex_file,
uint32_t offset_or_index,
vixl::aarch64::Label* adrp_label,
ArenaDeque<PcRelativePatchInfo>* patches) {
// Add a patch entry and return the label.
patches->emplace_back(dex_file, offset_or_index);
PcRelativePatchInfo* info = &patches->back();
vixl::aarch64::Label* label = &info->label;
// If adrp_label is null, this is the ADRP patch and needs to point to its own label.
info->pc_insn_label = (adrp_label != nullptr) ? adrp_label : label;
return label;
}
vixl::aarch64::Literal<uint32_t>* CodeGeneratorARM64::DeduplicateBootImageAddressLiteral(
uint64_t address) {
return DeduplicateUint32Literal(dchecked_integral_cast<uint32_t>(address));
}
vixl::aarch64::Literal<uint32_t>* CodeGeneratorARM64::DeduplicateJitStringLiteral(
const DexFile& dex_file, dex::StringIndex string_index, Handle<mirror::String> handle) {
ReserveJitStringRoot(StringReference(&dex_file, string_index), handle);
return jit_string_patches_.GetOrCreate(
StringReference(&dex_file, string_index),
[this]() { return __ CreateLiteralDestroyedWithPool<uint32_t>(/* placeholder */ 0u); });
}
vixl::aarch64::Literal<uint32_t>* CodeGeneratorARM64::DeduplicateJitClassLiteral(
const DexFile& dex_file, dex::TypeIndex type_index, Handle<mirror::Class> handle) {
ReserveJitClassRoot(TypeReference(&dex_file, type_index), handle);
return jit_class_patches_.GetOrCreate(
TypeReference(&dex_file, type_index),
[this]() { return __ CreateLiteralDestroyedWithPool<uint32_t>(/* placeholder */ 0u); });
}
void CodeGeneratorARM64::EmitAdrpPlaceholder(vixl::aarch64::Label* fixup_label,
vixl::aarch64::Register reg) {
DCHECK(reg.IsX());
SingleEmissionCheckScope guard(GetVIXLAssembler());
__ Bind(fixup_label);
__ adrp(reg, /* offset placeholder */ static_cast<int64_t>(0));
}
void CodeGeneratorARM64::EmitAddPlaceholder(vixl::aarch64::Label* fixup_label,
vixl::aarch64::Register out,
vixl::aarch64::Register base) {
DCHECK(out.IsX());
DCHECK(base.IsX());
SingleEmissionCheckScope guard(GetVIXLAssembler());
__ Bind(fixup_label);
__ add(out, base, Operand(/* offset placeholder */ 0));
}
void CodeGeneratorARM64::EmitLdrOffsetPlaceholder(vixl::aarch64::Label* fixup_label,
vixl::aarch64::Register out,
vixl::aarch64::Register base) {
DCHECK(base.IsX());
SingleEmissionCheckScope guard(GetVIXLAssembler());
__ Bind(fixup_label);
__ ldr(out, MemOperand(base, /* offset placeholder */ 0));
}
template <linker::LinkerPatch (*Factory)(size_t, const DexFile*, uint32_t, uint32_t)>
inline void CodeGeneratorARM64::EmitPcRelativeLinkerPatches(
const ArenaDeque<PcRelativePatchInfo>& infos,
ArenaVector<linker::LinkerPatch>* linker_patches) {
for (const PcRelativePatchInfo& info : infos) {
linker_patches->push_back(Factory(info.label.GetLocation(),
info.target_dex_file,
info.pc_insn_label->GetLocation(),
info.offset_or_index));
}
}
linker::LinkerPatch DataBimgRelRoPatchAdapter(size_t literal_offset,
const DexFile* target_dex_file,
uint32_t pc_insn_offset,
uint32_t boot_image_offset) {
DCHECK(target_dex_file == nullptr); // Unused for DataBimgRelRoPatch(), should be null.
return linker::LinkerPatch::DataBimgRelRoPatch(literal_offset, pc_insn_offset, boot_image_offset);
}
void CodeGeneratorARM64::EmitLinkerPatches(ArenaVector<linker::LinkerPatch>* linker_patches) {
DCHECK(linker_patches->empty());
size_t size =
boot_image_method_patches_.size() +
method_bss_entry_patches_.size() +
boot_image_type_patches_.size() +
type_bss_entry_patches_.size() +
boot_image_string_patches_.size() +
string_bss_entry_patches_.size() +
baker_read_barrier_patches_.size();
linker_patches->reserve(size);
if (GetCompilerOptions().IsBootImage()) {
EmitPcRelativeLinkerPatches<linker::LinkerPatch::RelativeMethodPatch>(
boot_image_method_patches_, linker_patches);
EmitPcRelativeLinkerPatches<linker::LinkerPatch::RelativeTypePatch>(
boot_image_type_patches_, linker_patches);
EmitPcRelativeLinkerPatches<linker::LinkerPatch::RelativeStringPatch>(
boot_image_string_patches_, linker_patches);
} else {
EmitPcRelativeLinkerPatches<DataBimgRelRoPatchAdapter>(
boot_image_method_patches_, linker_patches);
DCHECK(boot_image_type_patches_.empty());
DCHECK(boot_image_string_patches_.empty());
}
EmitPcRelativeLinkerPatches<linker::LinkerPatch::MethodBssEntryPatch>(
method_bss_entry_patches_, linker_patches);
EmitPcRelativeLinkerPatches<linker::LinkerPatch::TypeBssEntryPatch>(
type_bss_entry_patches_, linker_patches);
EmitPcRelativeLinkerPatches<linker::LinkerPatch::StringBssEntryPatch>(
string_bss_entry_patches_, linker_patches);
for (const BakerReadBarrierPatchInfo& info : baker_read_barrier_patches_) {
linker_patches->push_back(linker::LinkerPatch::BakerReadBarrierBranchPatch(
info.label.GetLocation(), info.custom_data));
}
DCHECK_EQ(size, linker_patches->size());
}
bool CodeGeneratorARM64::NeedsThunkCode(const linker::LinkerPatch& patch) const {
return patch.GetType() == linker::LinkerPatch::Type::kBakerReadBarrierBranch ||
patch.GetType() == linker::LinkerPatch::Type::kCallRelative;
}
void CodeGeneratorARM64::EmitThunkCode(const linker::LinkerPatch& patch,
/*out*/ ArenaVector<uint8_t>* code,
/*out*/ std::string* debug_name) {
Arm64Assembler assembler(GetGraph()->GetAllocator());
switch (patch.GetType()) {
case linker::LinkerPatch::Type::kCallRelative: {
// The thunk just uses the entry point in the ArtMethod. This works even for calls
// to the generic JNI and interpreter trampolines.
Offset offset(ArtMethod::EntryPointFromQuickCompiledCodeOffset(
kArm64PointerSize).Int32Value());
assembler.JumpTo(ManagedRegister(arm64::X0), offset, ManagedRegister(arm64::IP0));
if (GetCompilerOptions().GenerateAnyDebugInfo()) {
*debug_name = "MethodCallThunk";
}
break;
}
case linker::LinkerPatch::Type::kBakerReadBarrierBranch: {
DCHECK_EQ(patch.GetBakerCustomValue2(), 0u);
CompileBakerReadBarrierThunk(assembler, patch.GetBakerCustomValue1(), debug_name);
break;
}
default:
LOG(FATAL) << "Unexpected patch type " << patch.GetType();
UNREACHABLE();
}
// Ensure we emit the literal pool if any.
assembler.FinalizeCode();
code->resize(assembler.CodeSize());
MemoryRegion code_region(code->data(), code->size());
assembler.FinalizeInstructions(code_region);
}
vixl::aarch64::Literal<uint32_t>* CodeGeneratorARM64::DeduplicateUint32Literal(uint32_t value) {
return uint32_literals_.GetOrCreate(
value,
[this, value]() { return __ CreateLiteralDestroyedWithPool<uint32_t>(value); });
}
vixl::aarch64::Literal<uint64_t>* CodeGeneratorARM64::DeduplicateUint64Literal(uint64_t value) {
return uint64_literals_.GetOrCreate(
value,
[this, value]() { return __ CreateLiteralDestroyedWithPool<uint64_t>(value); });
}
void InstructionCodeGeneratorARM64::VisitInvokeStaticOrDirect(HInvokeStaticOrDirect* invoke) {
// Explicit clinit checks triggered by static invokes must have been pruned by
// art::PrepareForRegisterAllocation.
DCHECK(!invoke->IsStaticWithExplicitClinitCheck());
if (TryGenerateIntrinsicCode(invoke, codegen_)) {
codegen_->MaybeGenerateMarkingRegisterCheck(/* code */ __LINE__);
return;
}
{
// Ensure that between the BLR (emitted by GenerateStaticOrDirectCall) and RecordPcInfo there
// are no pools emitted.
EmissionCheckScope guard(GetVIXLAssembler(), kInvokeCodeMarginSizeInBytes);
LocationSummary* locations = invoke->GetLocations();
codegen_->GenerateStaticOrDirectCall(
invoke, locations->HasTemps() ? locations->GetTemp(0) : Location::NoLocation());
}
codegen_->MaybeGenerateMarkingRegisterCheck(/* code */ __LINE__);
}
void InstructionCodeGeneratorARM64::VisitInvokeVirtual(HInvokeVirtual* invoke) {
if (TryGenerateIntrinsicCode(invoke, codegen_)) {
codegen_->MaybeGenerateMarkingRegisterCheck(/* code */ __LINE__);
return;
}
{
// Ensure that between the BLR (emitted by GenerateVirtualCall) and RecordPcInfo there
// are no pools emitted.
EmissionCheckScope guard(GetVIXLAssembler(), kInvokeCodeMarginSizeInBytes);
codegen_->GenerateVirtualCall(invoke, invoke->GetLocations()->GetTemp(0));
DCHECK(!codegen_->IsLeafMethod());
}
codegen_->MaybeGenerateMarkingRegisterCheck(/* code */ __LINE__);
}
HLoadClass::LoadKind CodeGeneratorARM64::GetSupportedLoadClassKind(
HLoadClass::LoadKind desired_class_load_kind) {
switch (desired_class_load_kind) {
case HLoadClass::LoadKind::kInvalid:
LOG(FATAL) << "UNREACHABLE";
UNREACHABLE();
case HLoadClass::LoadKind::kReferrersClass:
break;
case HLoadClass::LoadKind::kBootImageLinkTimePcRelative:
case HLoadClass::LoadKind::kBootImageRelRo:
case HLoadClass::LoadKind::kBssEntry:
DCHECK(!Runtime::Current()->UseJitCompilation());
break;
case HLoadClass::LoadKind::kJitTableAddress:
DCHECK(Runtime::Current()->UseJitCompilation());
break;
case HLoadClass::LoadKind::kBootImageAddress:
case HLoadClass::LoadKind::kRuntimeCall:
break;
}
return desired_class_load_kind;
}
void LocationsBuilderARM64::VisitLoadClass(HLoadClass* cls) {
HLoadClass::LoadKind load_kind = cls->GetLoadKind();
if (load_kind == HLoadClass::LoadKind::kRuntimeCall) {
InvokeRuntimeCallingConvention calling_convention;
CodeGenerator::CreateLoadClassRuntimeCallLocationSummary(
cls,
LocationFrom(calling_convention.GetRegisterAt(0)),
LocationFrom(vixl::aarch64::x0));
DCHECK(calling_convention.GetRegisterAt(0).Is(vixl::aarch64::x0));
return;
}
DCHECK(!cls->NeedsAccessCheck());
const bool requires_read_barrier = kEmitCompilerReadBarrier && !cls->IsInBootImage();
LocationSummary::CallKind call_kind = (cls->NeedsEnvironment() || requires_read_barrier)
? LocationSummary::kCallOnSlowPath
: LocationSummary::kNoCall;
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(cls, call_kind);
if (kUseBakerReadBarrier && requires_read_barrier && !cls->NeedsEnvironment()) {
locations->SetCustomSlowPathCallerSaves(RegisterSet::Empty()); // No caller-save registers.
}
if (load_kind == HLoadClass::LoadKind::kReferrersClass) {
locations->SetInAt(0, Location::RequiresRegister());
}
locations->SetOut(Location::RequiresRegister());
if (cls->GetLoadKind() == HLoadClass::LoadKind::kBssEntry) {
if (!kUseReadBarrier || kUseBakerReadBarrier) {
// Rely on the type resolution or initialization and marking to save everything we need.
RegisterSet caller_saves = RegisterSet::Empty();
InvokeRuntimeCallingConvention calling_convention;
caller_saves.Add(Location::RegisterLocation(calling_convention.GetRegisterAt(0).GetCode()));
DCHECK_EQ(calling_convention.GetRegisterAt(0).GetCode(),
RegisterFrom(calling_convention.GetReturnLocation(DataType::Type::kReference),
DataType::Type::kReference).GetCode());
locations->SetCustomSlowPathCallerSaves(caller_saves);
} else {
// For non-Baker read barrier we have a temp-clobbering call.
}
}
}
// NO_THREAD_SAFETY_ANALYSIS as we manipulate handles whose internal object we know does not
// move.
void InstructionCodeGeneratorARM64::VisitLoadClass(HLoadClass* cls) NO_THREAD_SAFETY_ANALYSIS {
HLoadClass::LoadKind load_kind = cls->GetLoadKind();
if (load_kind == HLoadClass::LoadKind::kRuntimeCall) {
codegen_->GenerateLoadClassRuntimeCall(cls);
codegen_->MaybeGenerateMarkingRegisterCheck(/* code */ __LINE__);
return;
}
DCHECK(!cls->NeedsAccessCheck());
Location out_loc = cls->GetLocations()->Out();
Register out = OutputRegister(cls);
const ReadBarrierOption read_barrier_option = cls->IsInBootImage()
? kWithoutReadBarrier
: kCompilerReadBarrierOption;
bool generate_null_check = false;
switch (load_kind) {
case HLoadClass::LoadKind::kReferrersClass: {
DCHECK(!cls->CanCallRuntime());
DCHECK(!cls->MustGenerateClinitCheck());
// /* GcRoot<mirror::Class> */ out = current_method->declaring_class_
Register current_method = InputRegisterAt(cls, 0);
codegen_->GenerateGcRootFieldLoad(cls,
out_loc,
current_method,
ArtMethod::DeclaringClassOffset().Int32Value(),
/* fixup_label */ nullptr,
read_barrier_option);
break;
}
case HLoadClass::LoadKind::kBootImageLinkTimePcRelative: {
DCHECK_EQ(read_barrier_option, kWithoutReadBarrier);
// Add ADRP with its PC-relative type patch.
const DexFile& dex_file = cls->GetDexFile();
dex::TypeIndex type_index = cls->GetTypeIndex();
vixl::aarch64::Label* adrp_label = codegen_->NewBootImageTypePatch(dex_file, type_index);
codegen_->EmitAdrpPlaceholder(adrp_label, out.X());
// Add ADD with its PC-relative type patch.
vixl::aarch64::Label* add_label =
codegen_->NewBootImageTypePatch(dex_file, type_index, adrp_label);
codegen_->EmitAddPlaceholder(add_label, out.X(), out.X());
break;
}
case HLoadClass::LoadKind::kBootImageAddress: {
DCHECK_EQ(read_barrier_option, kWithoutReadBarrier);
uint32_t address = dchecked_integral_cast<uint32_t>(
reinterpret_cast<uintptr_t>(cls->GetClass().Get()));
DCHECK_NE(address, 0u);
__ Ldr(out.W(), codegen_->DeduplicateBootImageAddressLiteral(address));
break;
}
case HLoadClass::LoadKind::kBootImageRelRo: {
DCHECK(!codegen_->GetCompilerOptions().IsBootImage());
uint32_t boot_image_offset = codegen_->GetBootImageOffset(cls);
// Add ADRP with its PC-relative .data.bimg.rel.ro patch.
vixl::aarch64::Label* adrp_label = codegen_->NewBootImageRelRoPatch(boot_image_offset);
codegen_->EmitAdrpPlaceholder(adrp_label, out.X());
// Add LDR with its PC-relative .data.bimg.rel.ro patch.
vixl::aarch64::Label* ldr_label =
codegen_->NewBootImageRelRoPatch(boot_image_offset, adrp_label);
codegen_->EmitLdrOffsetPlaceholder(ldr_label, out.W(), out.X());
break;
}
case HLoadClass::LoadKind::kBssEntry: {
// Add ADRP with its PC-relative Class .bss entry patch.
const DexFile& dex_file = cls->GetDexFile();
dex::TypeIndex type_index = cls->GetTypeIndex();
vixl::aarch64::Register temp = XRegisterFrom(out_loc);
vixl::aarch64::Label* adrp_label = codegen_->NewBssEntryTypePatch(dex_file, type_index);
codegen_->EmitAdrpPlaceholder(adrp_label, temp);
// Add LDR with its PC-relative Class .bss entry patch.
vixl::aarch64::Label* ldr_label =
codegen_->NewBssEntryTypePatch(dex_file, type_index, adrp_label);
// /* GcRoot<mirror::Class> */ out = *(base_address + offset) /* PC-relative */
codegen_->GenerateGcRootFieldLoad(cls,
out_loc,
temp,
/* offset placeholder */ 0u,
ldr_label,
read_barrier_option);
generate_null_check = true;
break;
}
case HLoadClass::LoadKind::kJitTableAddress: {
__ Ldr(out, codegen_->DeduplicateJitClassLiteral(cls->GetDexFile(),
cls->GetTypeIndex(),
cls->GetClass()));
codegen_->GenerateGcRootFieldLoad(cls,
out_loc,
out.X(),
/* offset */ 0,
/* fixup_label */ nullptr,
read_barrier_option);
break;
}
case HLoadClass::LoadKind::kRuntimeCall:
case HLoadClass::LoadKind::kInvalid:
LOG(FATAL) << "UNREACHABLE";
UNREACHABLE();
}
bool do_clinit = cls->MustGenerateClinitCheck();
if (generate_null_check || do_clinit) {
DCHECK(cls->CanCallRuntime());
SlowPathCodeARM64* slow_path = new (codegen_->GetScopedAllocator()) LoadClassSlowPathARM64(
cls, cls, cls->GetDexPc(), do_clinit);
codegen_->AddSlowPath(slow_path);
if (generate_null_check) {
__ Cbz(out, slow_path->GetEntryLabel());
}
if (cls->MustGenerateClinitCheck()) {
GenerateClassInitializationCheck(slow_path, out);
} else {
__ Bind(slow_path->GetExitLabel());
}
codegen_->MaybeGenerateMarkingRegisterCheck(/* code */ __LINE__);
}
}
void LocationsBuilderARM64::VisitLoadMethodHandle(HLoadMethodHandle* load) {
InvokeRuntimeCallingConvention calling_convention;
Location location = LocationFrom(calling_convention.GetRegisterAt(0));
CodeGenerator::CreateLoadMethodHandleRuntimeCallLocationSummary(load, location, location);
}
void InstructionCodeGeneratorARM64::VisitLoadMethodHandle(HLoadMethodHandle* load) {
codegen_->GenerateLoadMethodHandleRuntimeCall(load);
}
void LocationsBuilderARM64::VisitLoadMethodType(HLoadMethodType* load) {
InvokeRuntimeCallingConvention calling_convention;
Location location = LocationFrom(calling_convention.GetRegisterAt(0));
CodeGenerator::CreateLoadMethodTypeRuntimeCallLocationSummary(load, location, location);
}
void InstructionCodeGeneratorARM64::VisitLoadMethodType(HLoadMethodType* load) {
codegen_->GenerateLoadMethodTypeRuntimeCall(load);
}
static MemOperand GetExceptionTlsAddress() {
return MemOperand(tr, Thread::ExceptionOffset<kArm64PointerSize>().Int32Value());
}
void LocationsBuilderARM64::VisitLoadException(HLoadException* load) {
LocationSummary* locations =
new (GetGraph()->GetAllocator()) LocationSummary(load, LocationSummary::kNoCall);
locations->SetOut(Location::RequiresRegister());
}
void InstructionCodeGeneratorARM64::VisitLoadException(HLoadException* instruction) {
__ Ldr(OutputRegister(instruction), GetExceptionTlsAddress());
}
void LocationsBuilderARM64::VisitClearException(HClearException* clear) {
new (GetGraph()->GetAllocator()) LocationSummary(clear, LocationSummary::kNoCall);
}
void InstructionCodeGeneratorARM64::VisitClearException(HClearException* clear ATTRIBUTE_UNUSED) {
__ Str(wzr, GetExceptionTlsAddress());
}
HLoadString::LoadKind CodeGeneratorARM64::GetSupportedLoadStringKind(
HLoadString::LoadKind desired_string_load_kind) {
switch (desired_string_load_kind) {
case HLoadString::LoadKind::kBootImageLinkTimePcRelative:
case HLoadString::LoadKind::kBootImageRelRo:
case HLoadString::LoadKind::kBssEntry:
DCHECK(!Runtime::Current()->UseJitCompilation());
break;
case HLoadString::LoadKind::kJitTableAddress:
DCHECK(Runtime::Current()->UseJitCompilation());
break;
case HLoadString::LoadKind::kBootImageAddress:
case HLoadString::LoadKind::kRuntimeCall:
break;
}
return desired_string_load_kind;
}
void LocationsBuilderARM64::VisitLoadString(HLoadString* load) {
LocationSummary::CallKind call_kind = CodeGenerator::GetLoadStringCallKind(load);
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(load, call_kind);
if (load->GetLoadKind() == HLoadString::LoadKind::kRuntimeCall) {
InvokeRuntimeCallingConvention calling_convention;
locations->SetOut(calling_convention.GetReturnLocation(load->GetType()));
} else {
locations->SetOut(Location::RequiresRegister());
if (load->GetLoadKind() == HLoadString::LoadKind::kBssEntry) {
if (!kUseReadBarrier || kUseBakerReadBarrier) {
// Rely on the pResolveString and marking to save everything we need.
RegisterSet caller_saves = RegisterSet::Empty();
InvokeRuntimeCallingConvention calling_convention;
caller_saves.Add(Location::RegisterLocation(calling_convention.GetRegisterAt(0).GetCode()));
DCHECK_EQ(calling_convention.GetRegisterAt(0).GetCode(),
RegisterFrom(calling_convention.GetReturnLocation(DataType::Type::kReference),
DataType::Type::kReference).GetCode());
locations->SetCustomSlowPathCallerSaves(caller_saves);
} else {
// For non-Baker read barrier we have a temp-clobbering call.
}
}
}
}
// NO_THREAD_SAFETY_ANALYSIS as we manipulate handles whose internal object we know does not
// move.
void InstructionCodeGeneratorARM64::VisitLoadString(HLoadString* load) NO_THREAD_SAFETY_ANALYSIS {
Register out = OutputRegister(load);
Location out_loc = load->GetLocations()->Out();
switch (load->GetLoadKind()) {
case HLoadString::LoadKind::kBootImageLinkTimePcRelative: {
DCHECK(codegen_->GetCompilerOptions().IsBootImage());
// Add ADRP with its PC-relative String patch.
const DexFile& dex_file = load->GetDexFile();
const dex::StringIndex string_index = load->GetStringIndex();
vixl::aarch64::Label* adrp_label = codegen_->NewBootImageStringPatch(dex_file, string_index);
codegen_->EmitAdrpPlaceholder(adrp_label, out.X());
// Add ADD with its PC-relative String patch.
vixl::aarch64::Label* add_label =
codegen_->NewBootImageStringPatch(dex_file, string_index, adrp_label);
codegen_->EmitAddPlaceholder(add_label, out.X(), out.X());
return;
}
case HLoadString::LoadKind::kBootImageAddress: {
uint32_t address = dchecked_integral_cast<uint32_t>(
reinterpret_cast<uintptr_t>(load->GetString().Get()));
DCHECK_NE(address, 0u);
__ Ldr(out.W(), codegen_->DeduplicateBootImageAddressLiteral(address));
return;
}
case HLoadString::LoadKind::kBootImageRelRo: {
DCHECK(!codegen_->GetCompilerOptions().IsBootImage());
// Add ADRP with its PC-relative .data.bimg.rel.ro patch.
uint32_t boot_image_offset = codegen_->GetBootImageOffset(load);
vixl::aarch64::Label* adrp_label = codegen_->NewBootImageRelRoPatch(boot_image_offset);
codegen_->EmitAdrpPlaceholder(adrp_label, out.X());
// Add LDR with its PC-relative .data.bimg.rel.ro patch.
vixl::aarch64::Label* ldr_label =
codegen_->NewBootImageRelRoPatch(boot_image_offset, adrp_label);
codegen_->EmitLdrOffsetPlaceholder(ldr_label, out.W(), out.X());
return;
}
case HLoadString::LoadKind::kBssEntry: {
// Add ADRP with its PC-relative String .bss entry patch.
const DexFile& dex_file = load->GetDexFile();
const dex::StringIndex string_index = load->GetStringIndex();
DCHECK(!codegen_->GetCompilerOptions().IsBootImage());
Register temp = XRegisterFrom(out_loc);
vixl::aarch64::Label* adrp_label = codegen_->NewStringBssEntryPatch(dex_file, string_index);
codegen_->EmitAdrpPlaceholder(adrp_label, temp);
// Add LDR with its PC-relative String .bss entry patch.
vixl::aarch64::Label* ldr_label =
codegen_->NewStringBssEntryPatch(dex_file, string_index, adrp_label);
// /* GcRoot<mirror::String> */ out = *(base_address + offset) /* PC-relative */
codegen_->GenerateGcRootFieldLoad(load,
out_loc,
temp,
/* offset placeholder */ 0u,
ldr_label,
kCompilerReadBarrierOption);
SlowPathCodeARM64* slow_path =
new (codegen_->GetScopedAllocator()) LoadStringSlowPathARM64(load);
codegen_->AddSlowPath(slow_path);
__ Cbz(out.X(), slow_path->GetEntryLabel());
__ Bind(slow_path->GetExitLabel());
codegen_->MaybeGenerateMarkingRegisterCheck(/* code */ __LINE__);
return;
}
case HLoadString::LoadKind::kJitTableAddress: {
__ Ldr(out, codegen_->DeduplicateJitStringLiteral(load->GetDexFile(),
load->GetStringIndex(),
load->GetString()));
codegen_->GenerateGcRootFieldLoad(load,
out_loc,
out.X(),
/* offset */ 0,
/* fixup_label */ nullptr,
kCompilerReadBarrierOption);
return;
}
default:
break;
}
// TODO: Re-add the compiler code to do string dex cache lookup again.
InvokeRuntimeCallingConvention calling_convention;
DCHECK_EQ(calling_convention.GetRegisterAt(0).GetCode(), out.GetCode());
__ Mov(calling_convention.GetRegisterAt(0).W(), load->GetStringIndex().index_);
codegen_->InvokeRuntime(kQuickResolveString, load, load->GetDexPc());
CheckEntrypointTypes<kQuickResolveString, void*, uint32_t>();
codegen_->MaybeGenerateMarkingRegisterCheck(/* code */ __LINE__);
}
void LocationsBuilderARM64::VisitLongConstant(HLongConstant* constant) {
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(constant);
locations->SetOut(Location::ConstantLocation(constant));
}
void InstructionCodeGeneratorARM64::VisitLongConstant(HLongConstant* constant ATTRIBUTE_UNUSED) {
// Will be generated at use site.
}
void LocationsBuilderARM64::VisitMonitorOperation(HMonitorOperation* instruction) {
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(
instruction, LocationSummary::kCallOnMainOnly);
InvokeRuntimeCallingConvention calling_convention;
locations->SetInAt(0, LocationFrom(calling_convention.GetRegisterAt(0)));
}
void InstructionCodeGeneratorARM64::VisitMonitorOperation(HMonitorOperation* instruction) {
codegen_->InvokeRuntime(instruction->IsEnter() ? kQuickLockObject : kQuickUnlockObject,
instruction,
instruction->GetDexPc());
if (instruction->IsEnter()) {
CheckEntrypointTypes<kQuickLockObject, void, mirror::Object*>();
} else {
CheckEntrypointTypes<kQuickUnlockObject, void, mirror::Object*>();
}
codegen_->MaybeGenerateMarkingRegisterCheck(/* code */ __LINE__);
}
void LocationsBuilderARM64::VisitMul(HMul* mul) {
LocationSummary* locations =
new (GetGraph()->GetAllocator()) LocationSummary(mul, LocationSummary::kNoCall);
switch (mul->GetResultType()) {
case DataType::Type::kInt32:
case DataType::Type::kInt64:
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
break;
case DataType::Type::kFloat32:
case DataType::Type::kFloat64:
locations->SetInAt(0, Location::RequiresFpuRegister());
locations->SetInAt(1, Location::RequiresFpuRegister());
locations->SetOut(Location::RequiresFpuRegister(), Location::kNoOutputOverlap);
break;
default:
LOG(FATAL) << "Unexpected mul type " << mul->GetResultType();
}
}
void InstructionCodeGeneratorARM64::VisitMul(HMul* mul) {
switch (mul->GetResultType()) {
case DataType::Type::kInt32:
case DataType::Type::kInt64:
__ Mul(OutputRegister(mul), InputRegisterAt(mul, 0), InputRegisterAt(mul, 1));
break;
case DataType::Type::kFloat32:
case DataType::Type::kFloat64:
__ Fmul(OutputFPRegister(mul), InputFPRegisterAt(mul, 0), InputFPRegisterAt(mul, 1));
break;
default:
LOG(FATAL) << "Unexpected mul type " << mul->GetResultType();
}
}
void LocationsBuilderARM64::VisitNeg(HNeg* neg) {
LocationSummary* locations =
new (GetGraph()->GetAllocator()) LocationSummary(neg, LocationSummary::kNoCall);
switch (neg->GetResultType()) {
case DataType::Type::kInt32:
case DataType::Type::kInt64:
locations->SetInAt(0, ARM64EncodableConstantOrRegister(neg->InputAt(0), neg));
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
break;
case DataType::Type::kFloat32:
case DataType::Type::kFloat64:
locations->SetInAt(0, Location::RequiresFpuRegister());
locations->SetOut(Location::RequiresFpuRegister(), Location::kNoOutputOverlap);
break;
default:
LOG(FATAL) << "Unexpected neg type " << neg->GetResultType();
}
}
void InstructionCodeGeneratorARM64::VisitNeg(HNeg* neg) {
switch (neg->GetResultType()) {
case DataType::Type::kInt32:
case DataType::Type::kInt64:
__ Neg(OutputRegister(neg), InputOperandAt(neg, 0));
break;
case DataType::Type::kFloat32:
case DataType::Type::kFloat64:
__ Fneg(OutputFPRegister(neg), InputFPRegisterAt(neg, 0));
break;
default:
LOG(FATAL) << "Unexpected neg type " << neg->GetResultType();
}
}
void LocationsBuilderARM64::VisitNewArray(HNewArray* instruction) {
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(
instruction, LocationSummary::kCallOnMainOnly);
InvokeRuntimeCallingConvention calling_convention;
locations->SetOut(LocationFrom(x0));
locations->SetInAt(0, LocationFrom(calling_convention.GetRegisterAt(0)));
locations->SetInAt(1, LocationFrom(calling_convention.GetRegisterAt(1)));
}
void InstructionCodeGeneratorARM64::VisitNewArray(HNewArray* instruction) {
// Note: if heap poisoning is enabled, the entry point takes cares
// of poisoning the reference.
QuickEntrypointEnum entrypoint =
CodeGenerator::GetArrayAllocationEntrypoint(instruction->GetLoadClass()->GetClass());
codegen_->InvokeRuntime(entrypoint, instruction, instruction->GetDexPc());
CheckEntrypointTypes<kQuickAllocArrayResolved, void*, mirror::Class*, int32_t>();
codegen_->MaybeGenerateMarkingRegisterCheck(/* code */ __LINE__);
}
void LocationsBuilderARM64::VisitNewInstance(HNewInstance* instruction) {
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(
instruction, LocationSummary::kCallOnMainOnly);
InvokeRuntimeCallingConvention calling_convention;
if (instruction->IsStringAlloc()) {
locations->AddTemp(LocationFrom(kArtMethodRegister));
} else {
locations->SetInAt(0, LocationFrom(calling_convention.GetRegisterAt(0)));
}
locations->SetOut(calling_convention.GetReturnLocation(DataType::Type::kReference));
}
void InstructionCodeGeneratorARM64::VisitNewInstance(HNewInstance* instruction) {
// Note: if heap poisoning is enabled, the entry point takes cares
// of poisoning the reference.
if (instruction->IsStringAlloc()) {
// String is allocated through StringFactory. Call NewEmptyString entry point.
Location temp = instruction->GetLocations()->GetTemp(0);
MemberOffset code_offset = ArtMethod::EntryPointFromQuickCompiledCodeOffset(kArm64PointerSize);
__ Ldr(XRegisterFrom(temp), MemOperand(tr, QUICK_ENTRY_POINT(pNewEmptyString)));
__ Ldr(lr, MemOperand(XRegisterFrom(temp), code_offset.Int32Value()));
{
// Ensure the pc position is recorded immediately after the `blr` instruction.
ExactAssemblyScope eas(GetVIXLAssembler(),
kInstructionSize,
CodeBufferCheckScope::kExactSize);
__ blr(lr);
codegen_->RecordPcInfo(instruction, instruction->GetDexPc());
}
} else {
codegen_->InvokeRuntime(instruction->GetEntrypoint(), instruction, instruction->GetDexPc());
CheckEntrypointTypes<kQuickAllocObjectWithChecks, void*, mirror::Class*>();
}
codegen_->MaybeGenerateMarkingRegisterCheck(/* code */ __LINE__);
}
void LocationsBuilderARM64::VisitNot(HNot* instruction) {
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(instruction);
locations->SetInAt(0, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
}
void InstructionCodeGeneratorARM64::VisitNot(HNot* instruction) {
switch (instruction->GetResultType()) {
case DataType::Type::kInt32:
case DataType::Type::kInt64:
__ Mvn(OutputRegister(instruction), InputOperandAt(instruction, 0));
break;
default:
LOG(FATAL) << "Unexpected type for not operation " << instruction->GetResultType();
}
}
void LocationsBuilderARM64::VisitBooleanNot(HBooleanNot* instruction) {
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(instruction);
locations->SetInAt(0, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
}
void InstructionCodeGeneratorARM64::VisitBooleanNot(HBooleanNot* instruction) {
__ Eor(OutputRegister(instruction), InputRegisterAt(instruction, 0), vixl::aarch64::Operand(1));
}
void LocationsBuilderARM64::VisitNullCheck(HNullCheck* instruction) {
LocationSummary* locations = codegen_->CreateThrowingSlowPathLocations(instruction);
locations->SetInAt(0, Location::RequiresRegister());
}
void CodeGeneratorARM64::GenerateImplicitNullCheck(HNullCheck* instruction) {
if (CanMoveNullCheckToUser(instruction)) {
return;
}
{
// Ensure that between load and MaybeRecordImplicitNullCheck there are no pools emitted.
EmissionCheckScope guard(GetVIXLAssembler(), kMaxMacroInstructionSizeInBytes);
Location obj = instruction->GetLocations()->InAt(0);
__ Ldr(wzr, HeapOperandFrom(obj, Offset(0)));
RecordPcInfo(instruction, instruction->GetDexPc());
}
}
void CodeGeneratorARM64::GenerateExplicitNullCheck(HNullCheck* instruction) {
SlowPathCodeARM64* slow_path = new (GetScopedAllocator()) NullCheckSlowPathARM64(instruction);
AddSlowPath(slow_path);
LocationSummary* locations = instruction->GetLocations();
Location obj = locations->InAt(0);
__ Cbz(RegisterFrom(obj, instruction->InputAt(0)->GetType()), slow_path->GetEntryLabel());
}
void InstructionCodeGeneratorARM64::VisitNullCheck(HNullCheck* instruction) {
codegen_->GenerateNullCheck(instruction);
}
void LocationsBuilderARM64::VisitOr(HOr* instruction) {
HandleBinaryOp(instruction);
}
void InstructionCodeGeneratorARM64::VisitOr(HOr* instruction) {
HandleBinaryOp(instruction);
}
void LocationsBuilderARM64::VisitParallelMove(HParallelMove* instruction ATTRIBUTE_UNUSED) {
LOG(FATAL) << "Unreachable";
}
void InstructionCodeGeneratorARM64::VisitParallelMove(HParallelMove* instruction) {
if (instruction->GetNext()->IsSuspendCheck() &&
instruction->GetBlock()->GetLoopInformation() != nullptr) {
HSuspendCheck* suspend_check = instruction->GetNext()->AsSuspendCheck();
// The back edge will generate the suspend check.
codegen_->ClearSpillSlotsFromLoopPhisInStackMap(suspend_check, instruction);
}
codegen_->GetMoveResolver()->EmitNativeCode(instruction);
}
void LocationsBuilderARM64::VisitParameterValue(HParameterValue* instruction) {
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(instruction);
Location location = parameter_visitor_.GetNextLocation(instruction->GetType());
if (location.IsStackSlot()) {
location = Location::StackSlot(location.GetStackIndex() + codegen_->GetFrameSize());
} else if (location.IsDoubleStackSlot()) {
location = Location::DoubleStackSlot(location.GetStackIndex() + codegen_->GetFrameSize());
}
locations->SetOut(location);
}
void InstructionCodeGeneratorARM64::VisitParameterValue(
HParameterValue* instruction ATTRIBUTE_UNUSED) {
// Nothing to do, the parameter is already at its location.
}
void LocationsBuilderARM64::VisitCurrentMethod(HCurrentMethod* instruction) {
LocationSummary* locations =
new (GetGraph()->GetAllocator()) LocationSummary(instruction, LocationSummary::kNoCall);
locations->SetOut(LocationFrom(kArtMethodRegister));
}
void InstructionCodeGeneratorARM64::VisitCurrentMethod(
HCurrentMethod* instruction ATTRIBUTE_UNUSED) {
// Nothing to do, the method is already at its location.
}
void LocationsBuilderARM64::VisitPhi(HPhi* instruction) {
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(instruction);
for (size_t i = 0, e = locations->GetInputCount(); i < e; ++i) {
locations->SetInAt(i, Location::Any());
}
locations->SetOut(Location::Any());
}
void InstructionCodeGeneratorARM64::VisitPhi(HPhi* instruction ATTRIBUTE_UNUSED) {
LOG(FATAL) << "Unreachable";
}
void LocationsBuilderARM64::VisitRem(HRem* rem) {
DataType::Type type = rem->GetResultType();
LocationSummary::CallKind call_kind =
DataType::IsFloatingPointType(type) ? LocationSummary::kCallOnMainOnly
: LocationSummary::kNoCall;
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(rem, call_kind);
switch (type) {
case DataType::Type::kInt32:
case DataType::Type::kInt64:
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RegisterOrConstant(rem->InputAt(1)));
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
break;
case DataType::Type::kFloat32:
case DataType::Type::kFloat64: {
InvokeRuntimeCallingConvention calling_convention;
locations->SetInAt(0, LocationFrom(calling_convention.GetFpuRegisterAt(0)));
locations->SetInAt(1, LocationFrom(calling_convention.GetFpuRegisterAt(1)));
locations->SetOut(calling_convention.GetReturnLocation(type));
break;
}
default:
LOG(FATAL) << "Unexpected rem type " << type;
}
}
void InstructionCodeGeneratorARM64::VisitRem(HRem* rem) {
DataType::Type type = rem->GetResultType();
switch (type) {
case DataType::Type::kInt32:
case DataType::Type::kInt64: {
GenerateDivRemIntegral(rem);
break;
}
case DataType::Type::kFloat32:
case DataType::Type::kFloat64: {
QuickEntrypointEnum entrypoint =
(type == DataType::Type::kFloat32) ? kQuickFmodf : kQuickFmod;
codegen_->InvokeRuntime(entrypoint, rem, rem->GetDexPc());
if (type == DataType::Type::kFloat32) {
CheckEntrypointTypes<kQuickFmodf, float, float, float>();
} else {
CheckEntrypointTypes<kQuickFmod, double, double, double>();
}
break;
}
default:
LOG(FATAL) << "Unexpected rem type " << type;
UNREACHABLE();
}
}
// TODO: integrate with HandleBinaryOp?
static void CreateMinMaxLocations(ArenaAllocator* allocator, HBinaryOperation* minmax) {
LocationSummary* locations = new (allocator) LocationSummary(minmax);
switch (minmax->GetResultType()) {
case DataType::Type::kInt32:
case DataType::Type::kInt64:
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
break;
case DataType::Type::kFloat32:
case DataType::Type::kFloat64:
locations->SetInAt(0, Location::RequiresFpuRegister());
locations->SetInAt(1, Location::RequiresFpuRegister());
locations->SetOut(Location::RequiresFpuRegister(), Location::kNoOutputOverlap);
break;
default:
LOG(FATAL) << "Unexpected type for HMinMax " << minmax->GetResultType();
}
}
void InstructionCodeGeneratorARM64::GenerateMinMaxInt(LocationSummary* locations,
bool is_min,
DataType::Type type) {
Location op1 = locations->InAt(0);
Location op2 = locations->InAt(1);
Location out = locations->Out();
Register op1_reg;
Register op2_reg;
Register out_reg;
if (type == DataType::Type::kInt64) {
op1_reg = XRegisterFrom(op1);
op2_reg = XRegisterFrom(op2);
out_reg = XRegisterFrom(out);
} else {
DCHECK_EQ(type, DataType::Type::kInt32);
op1_reg = WRegisterFrom(op1);
op2_reg = WRegisterFrom(op2);
out_reg = WRegisterFrom(out);
}
__ Cmp(op1_reg, op2_reg);
__ Csel(out_reg, op1_reg, op2_reg, is_min ? lt : gt);
}
void InstructionCodeGeneratorARM64::GenerateMinMaxFP(LocationSummary* locations,
bool is_min,
DataType::Type type) {
Location op1 = locations->InAt(0);
Location op2 = locations->InAt(1);
Location out = locations->Out();
FPRegister op1_reg;
FPRegister op2_reg;
FPRegister out_reg;
if (type == DataType::Type::kFloat64) {
op1_reg = DRegisterFrom(op1);
op2_reg = DRegisterFrom(op2);
out_reg = DRegisterFrom(out);
} else {
DCHECK_EQ(type, DataType::Type::kFloat32);
op1_reg = SRegisterFrom(op1);
op2_reg = SRegisterFrom(op2);
out_reg = SRegisterFrom(out);
}
if (is_min) {
__ Fmin(out_reg, op1_reg, op2_reg);
} else {
__ Fmax(out_reg, op1_reg, op2_reg);
}
}
// TODO: integrate with HandleBinaryOp?
void InstructionCodeGeneratorARM64::GenerateMinMax(HBinaryOperation* minmax, bool is_min) {
DataType::Type type = minmax->GetResultType();
switch (type) {
case DataType::Type::kInt32:
case DataType::Type::kInt64:
GenerateMinMaxInt(minmax->GetLocations(), is_min, type);
break;
case DataType::Type::kFloat32:
case DataType::Type::kFloat64:
GenerateMinMaxFP(minmax->GetLocations(), is_min, type);
break;
default:
LOG(FATAL) << "Unexpected type for HMinMax " << type;
}
}
void LocationsBuilderARM64::VisitMin(HMin* min) {
CreateMinMaxLocations(GetGraph()->GetAllocator(), min);
}
void InstructionCodeGeneratorARM64::VisitMin(HMin* min) {
GenerateMinMax(min, /*is_min*/ true);
}
void LocationsBuilderARM64::VisitMax(HMax* max) {
CreateMinMaxLocations(GetGraph()->GetAllocator(), max);
}
void InstructionCodeGeneratorARM64::VisitMax(HMax* max) {
GenerateMinMax(max, /*is_min*/ false);
}
void LocationsBuilderARM64::VisitAbs(HAbs* abs) {
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(abs);
switch (abs->GetResultType()) {
case DataType::Type::kInt32:
case DataType::Type::kInt64:
locations->SetInAt(0, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
break;
case DataType::Type::kFloat32:
case DataType::Type::kFloat64:
locations->SetInAt(0, Location::RequiresFpuRegister());
locations->SetOut(Location::RequiresFpuRegister(), Location::kNoOutputOverlap);
break;
default:
LOG(FATAL) << "Unexpected type for abs operation " << abs->GetResultType();
}
}
void InstructionCodeGeneratorARM64::VisitAbs(HAbs* abs) {
switch (abs->GetResultType()) {
case DataType::Type::kInt32:
case DataType::Type::kInt64: {
Register in_reg = InputRegisterAt(abs, 0);
Register out_reg = OutputRegister(abs);
__ Cmp(in_reg, Operand(0));
__ Cneg(out_reg, in_reg, lt);
break;
}
case DataType::Type::kFloat32:
case DataType::Type::kFloat64: {
FPRegister in_reg = InputFPRegisterAt(abs, 0);
FPRegister out_reg = OutputFPRegister(abs);
__ Fabs(out_reg, in_reg);
break;
}
default:
LOG(FATAL) << "Unexpected type for abs operation " << abs->GetResultType();
}
}
void LocationsBuilderARM64::VisitConstructorFence(HConstructorFence* constructor_fence) {
constructor_fence->SetLocations(nullptr);
}
void InstructionCodeGeneratorARM64::VisitConstructorFence(
HConstructorFence* constructor_fence ATTRIBUTE_UNUSED) {
codegen_->GenerateMemoryBarrier(MemBarrierKind::kStoreStore);
}
void LocationsBuilderARM64::VisitMemoryBarrier(HMemoryBarrier* memory_barrier) {
memory_barrier->SetLocations(nullptr);
}
void InstructionCodeGeneratorARM64::VisitMemoryBarrier(HMemoryBarrier* memory_barrier) {
codegen_->GenerateMemoryBarrier(memory_barrier->GetBarrierKind());
}
void LocationsBuilderARM64::VisitReturn(HReturn* instruction) {
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(instruction);
DataType::Type return_type = instruction->InputAt(0)->GetType();
locations->SetInAt(0, ARM64ReturnLocation(return_type));
}
void InstructionCodeGeneratorARM64::VisitReturn(HReturn* instruction ATTRIBUTE_UNUSED) {
codegen_->GenerateFrameExit();
}
void LocationsBuilderARM64::VisitReturnVoid(HReturnVoid* instruction) {
instruction->SetLocations(nullptr);
}
void InstructionCodeGeneratorARM64::VisitReturnVoid(HReturnVoid* instruction ATTRIBUTE_UNUSED) {
codegen_->GenerateFrameExit();
}
void LocationsBuilderARM64::VisitRor(HRor* ror) {
HandleBinaryOp(ror);
}
void InstructionCodeGeneratorARM64::VisitRor(HRor* ror) {
HandleBinaryOp(ror);
}
void LocationsBuilderARM64::VisitShl(HShl* shl) {
HandleShift(shl);
}
void InstructionCodeGeneratorARM64::VisitShl(HShl* shl) {
HandleShift(shl);
}
void LocationsBuilderARM64::VisitShr(HShr* shr) {
HandleShift(shr);
}
void InstructionCodeGeneratorARM64::VisitShr(HShr* shr) {
HandleShift(shr);
}
void LocationsBuilderARM64::VisitSub(HSub* instruction) {
HandleBinaryOp(instruction);
}
void InstructionCodeGeneratorARM64::VisitSub(HSub* instruction) {
HandleBinaryOp(instruction);
}
void LocationsBuilderARM64::VisitStaticFieldGet(HStaticFieldGet* instruction) {
HandleFieldGet(instruction, instruction->GetFieldInfo());
}
void InstructionCodeGeneratorARM64::VisitStaticFieldGet(HStaticFieldGet* instruction) {
HandleFieldGet(instruction, instruction->GetFieldInfo());
}
void LocationsBuilderARM64::VisitStaticFieldSet(HStaticFieldSet* instruction) {
HandleFieldSet(instruction);
}
void InstructionCodeGeneratorARM64::VisitStaticFieldSet(HStaticFieldSet* instruction) {
HandleFieldSet(instruction, instruction->GetFieldInfo(), instruction->GetValueCanBeNull());
}
void LocationsBuilderARM64::VisitUnresolvedInstanceFieldGet(
HUnresolvedInstanceFieldGet* instruction) {
FieldAccessCallingConventionARM64 calling_convention;
codegen_->CreateUnresolvedFieldLocationSummary(
instruction, instruction->GetFieldType(), calling_convention);
}
void InstructionCodeGeneratorARM64::VisitUnresolvedInstanceFieldGet(
HUnresolvedInstanceFieldGet* instruction) {
FieldAccessCallingConventionARM64 calling_convention;
codegen_->GenerateUnresolvedFieldAccess(instruction,
instruction->GetFieldType(),
instruction->GetFieldIndex(),
instruction->GetDexPc(),
calling_convention);
}
void LocationsBuilderARM64::VisitUnresolvedInstanceFieldSet(
HUnresolvedInstanceFieldSet* instruction) {
FieldAccessCallingConventionARM64 calling_convention;
codegen_->CreateUnresolvedFieldLocationSummary(
instruction, instruction->GetFieldType(), calling_convention);
}
void InstructionCodeGeneratorARM64::VisitUnresolvedInstanceFieldSet(
HUnresolvedInstanceFieldSet* instruction) {
FieldAccessCallingConventionARM64 calling_convention;
codegen_->GenerateUnresolvedFieldAccess(instruction,
instruction->GetFieldType(),
instruction->GetFieldIndex(),
instruction->GetDexPc(),
calling_convention);
}
void LocationsBuilderARM64::VisitUnresolvedStaticFieldGet(
HUnresolvedStaticFieldGet* instruction) {
FieldAccessCallingConventionARM64 calling_convention;
codegen_->CreateUnresolvedFieldLocationSummary(
instruction, instruction->GetFieldType(), calling_convention);
}
void InstructionCodeGeneratorARM64::VisitUnresolvedStaticFieldGet(
HUnresolvedStaticFieldGet* instruction) {
FieldAccessCallingConventionARM64 calling_convention;
codegen_->GenerateUnresolvedFieldAccess(instruction,
instruction->GetFieldType(),
instruction->GetFieldIndex(),
instruction->GetDexPc(),
calling_convention);
}
void LocationsBuilderARM64::VisitUnresolvedStaticFieldSet(
HUnresolvedStaticFieldSet* instruction) {
FieldAccessCallingConventionARM64 calling_convention;
codegen_->CreateUnresolvedFieldLocationSummary(
instruction, instruction->GetFieldType(), calling_convention);
}
void InstructionCodeGeneratorARM64::VisitUnresolvedStaticFieldSet(
HUnresolvedStaticFieldSet* instruction) {
FieldAccessCallingConventionARM64 calling_convention;
codegen_->GenerateUnresolvedFieldAccess(instruction,
instruction->GetFieldType(),
instruction->GetFieldIndex(),
instruction->GetDexPc(),
calling_convention);
}
void LocationsBuilderARM64::VisitSuspendCheck(HSuspendCheck* instruction) {
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(
instruction, LocationSummary::kCallOnSlowPath);
// In suspend check slow path, usually there are no caller-save registers at all.
// If SIMD instructions are present, however, we force spilling all live SIMD
// registers in full width (since the runtime only saves/restores lower part).
locations->SetCustomSlowPathCallerSaves(
GetGraph()->HasSIMD() ? RegisterSet::AllFpu() : RegisterSet::Empty());
}
void InstructionCodeGeneratorARM64::VisitSuspendCheck(HSuspendCheck* instruction) {
HBasicBlock* block = instruction->GetBlock();
if (block->GetLoopInformation() != nullptr) {
DCHECK(block->GetLoopInformation()->GetSuspendCheck() == instruction);
// The back edge will generate the suspend check.
return;
}
if (block->IsEntryBlock() && instruction->GetNext()->IsGoto()) {
// The goto will generate the suspend check.
return;
}
GenerateSuspendCheck(instruction, nullptr);
codegen_->MaybeGenerateMarkingRegisterCheck(/* code */ __LINE__);
}
void LocationsBuilderARM64::VisitThrow(HThrow* instruction) {
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(
instruction, LocationSummary::kCallOnMainOnly);
InvokeRuntimeCallingConvention calling_convention;
locations->SetInAt(0, LocationFrom(calling_convention.GetRegisterAt(0)));
}
void InstructionCodeGeneratorARM64::VisitThrow(HThrow* instruction) {
codegen_->InvokeRuntime(kQuickDeliverException, instruction, instruction->GetDexPc());
CheckEntrypointTypes<kQuickDeliverException, void, mirror::Object*>();
}
void LocationsBuilderARM64::VisitTypeConversion(HTypeConversion* conversion) {
LocationSummary* locations =
new (GetGraph()->GetAllocator()) LocationSummary(conversion, LocationSummary::kNoCall);
DataType::Type input_type = conversion->GetInputType();
DataType::Type result_type = conversion->GetResultType();
DCHECK(!DataType::IsTypeConversionImplicit(input_type, result_type))
<< input_type << " -> " << result_type;
if ((input_type == DataType::Type::kReference) || (input_type == DataType::Type::kVoid) ||
(result_type == DataType::Type::kReference) || (result_type == DataType::Type::kVoid)) {
LOG(FATAL) << "Unexpected type conversion from " << input_type << " to " << result_type;
}
if (DataType::IsFloatingPointType(input_type)) {
locations->SetInAt(0, Location::RequiresFpuRegister());
} else {
locations->SetInAt(0, Location::RequiresRegister());
}
if (DataType::IsFloatingPointType(result_type)) {
locations->SetOut(Location::RequiresFpuRegister(), Location::kNoOutputOverlap);
} else {
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
}
}
void InstructionCodeGeneratorARM64::VisitTypeConversion(HTypeConversion* conversion) {
DataType::Type result_type = conversion->GetResultType();
DataType::Type input_type = conversion->GetInputType();
DCHECK(!DataType::IsTypeConversionImplicit(input_type, result_type))
<< input_type << " -> " << result_type;
if (DataType::IsIntegralType(result_type) && DataType::IsIntegralType(input_type)) {
int result_size = DataType::Size(result_type);
int input_size = DataType::Size(input_type);
int min_size = std::min(result_size, input_size);
Register output = OutputRegister(conversion);
Register source = InputRegisterAt(conversion, 0);
if (result_type == DataType::Type::kInt32 && input_type == DataType::Type::kInt64) {
// 'int' values are used directly as W registers, discarding the top
// bits, so we don't need to sign-extend and can just perform a move.
// We do not pass the `kDiscardForSameWReg` argument to force clearing the
// top 32 bits of the target register. We theoretically could leave those
// bits unchanged, but we would have to make sure that no code uses a
// 32bit input value as a 64bit value assuming that the top 32 bits are
// zero.
__ Mov(output.W(), source.W());
} else if (DataType::IsUnsignedType(result_type) ||
(DataType::IsUnsignedType(input_type) && input_size < result_size)) {
__ Ubfx(output, output.IsX() ? source.X() : source.W(), 0, result_size * kBitsPerByte);
} else {
__ Sbfx(output, output.IsX() ? source.X() : source.W(), 0, min_size * kBitsPerByte);
}
} else if (DataType::IsFloatingPointType(result_type) && DataType::IsIntegralType(input_type)) {
__ Scvtf(OutputFPRegister(conversion), InputRegisterAt(conversion, 0));
} else if (DataType::IsIntegralType(result_type) && DataType::IsFloatingPointType(input_type)) {
CHECK(result_type == DataType::Type::kInt32 || result_type == DataType::Type::kInt64);
__ Fcvtzs(OutputRegister(conversion), InputFPRegisterAt(conversion, 0));
} else if (DataType::IsFloatingPointType(result_type) &&
DataType::IsFloatingPointType(input_type)) {
__ Fcvt(OutputFPRegister(conversion), InputFPRegisterAt(conversion, 0));
} else {
LOG(FATAL) << "Unexpected or unimplemented type conversion from " << input_type
<< " to " << result_type;
}
}
void LocationsBuilderARM64::VisitUShr(HUShr* ushr) {
HandleShift(ushr);
}
void InstructionCodeGeneratorARM64::VisitUShr(HUShr* ushr) {
HandleShift(ushr);
}
void LocationsBuilderARM64::VisitXor(HXor* instruction) {
HandleBinaryOp(instruction);
}
void InstructionCodeGeneratorARM64::VisitXor(HXor* instruction) {
HandleBinaryOp(instruction);
}
void LocationsBuilderARM64::VisitBoundType(HBoundType* instruction ATTRIBUTE_UNUSED) {
// Nothing to do, this should be removed during prepare for register allocator.
LOG(FATAL) << "Unreachable";
}
void InstructionCodeGeneratorARM64::VisitBoundType(HBoundType* instruction ATTRIBUTE_UNUSED) {
// Nothing to do, this should be removed during prepare for register allocator.
LOG(FATAL) << "Unreachable";
}
// Simple implementation of packed switch - generate cascaded compare/jumps.
void LocationsBuilderARM64::VisitPackedSwitch(HPackedSwitch* switch_instr) {
LocationSummary* locations =
new (GetGraph()->GetAllocator()) LocationSummary(switch_instr, LocationSummary::kNoCall);
locations->SetInAt(0, Location::RequiresRegister());
}
void InstructionCodeGeneratorARM64::VisitPackedSwitch(HPackedSwitch* switch_instr) {
int32_t lower_bound = switch_instr->GetStartValue();
uint32_t num_entries = switch_instr->GetNumEntries();
Register value_reg = InputRegisterAt(switch_instr, 0);
HBasicBlock* default_block = switch_instr->GetDefaultBlock();
// Roughly set 16 as max average assemblies generated per HIR in a graph.
static constexpr int32_t kMaxExpectedSizePerHInstruction = 16 * kInstructionSize;
// ADR has a limited range(+/-1MB), so we set a threshold for the number of HIRs in the graph to
// make sure we don't emit it if the target may run out of range.
// TODO: Instead of emitting all jump tables at the end of the code, we could keep track of ADR
// ranges and emit the tables only as required.
static constexpr int32_t kJumpTableInstructionThreshold = 1* MB / kMaxExpectedSizePerHInstruction;
if (num_entries <= kPackedSwitchCompareJumpThreshold ||
// Current instruction id is an upper bound of the number of HIRs in the graph.
GetGraph()->GetCurrentInstructionId() > kJumpTableInstructionThreshold) {
// Create a series of compare/jumps.
UseScratchRegisterScope temps(codegen_->GetVIXLAssembler());
Register temp = temps.AcquireW();
__ Subs(temp, value_reg, Operand(lower_bound));
const ArenaVector<HBasicBlock*>& successors = switch_instr->GetBlock()->GetSuccessors();
// Jump to successors[0] if value == lower_bound.
__ B(eq, codegen_->GetLabelOf(successors[0]));
int32_t last_index = 0;
for (; num_entries - last_index > 2; last_index += 2) {
__ Subs(temp, temp, Operand(2));
// Jump to successors[last_index + 1] if value < case_value[last_index + 2].
__ B(lo, codegen_->GetLabelOf(successors[last_index + 1]));
// Jump to successors[last_index + 2] if value == case_value[last_index + 2].
__ B(eq, codegen_->GetLabelOf(successors[last_index + 2]));
}
if (num_entries - last_index == 2) {
// The last missing case_value.
__ Cmp(temp, Operand(1));
__ B(eq, codegen_->GetLabelOf(successors[last_index + 1]));
}
// And the default for any other value.
if (!codegen_->GoesToNextBlock(switch_instr->GetBlock(), default_block)) {
__ B(codegen_->GetLabelOf(default_block));
}
} else {
JumpTableARM64* jump_table = codegen_->CreateJumpTable(switch_instr);
UseScratchRegisterScope temps(codegen_->GetVIXLAssembler());
// Below instructions should use at most one blocked register. Since there are two blocked
// registers, we are free to block one.
Register temp_w = temps.AcquireW();
Register index;
// Remove the bias.
if (lower_bound != 0) {
index = temp_w;
__ Sub(index, value_reg, Operand(lower_bound));
} else {
index = value_reg;
}
// Jump to default block if index is out of the range.
__ Cmp(index, Operand(num_entries));
__ B(hs, codegen_->GetLabelOf(default_block));
// In current VIXL implementation, it won't require any blocked registers to encode the
// immediate value for Adr. So we are free to use both VIXL blocked registers to reduce the
// register pressure.
Register table_base = temps.AcquireX();
// Load jump offset from the table.
__ Adr(table_base, jump_table->GetTableStartLabel());
Register jump_offset = temp_w;
__ Ldr(jump_offset, MemOperand(table_base, index, UXTW, 2));
// Jump to target block by branching to table_base(pc related) + offset.
Register target_address = table_base;
__ Add(target_address, table_base, Operand(jump_offset, SXTW));
__ Br(target_address);
}
}
void InstructionCodeGeneratorARM64::GenerateReferenceLoadOneRegister(
HInstruction* instruction,
Location out,
uint32_t offset,
Location maybe_temp,
ReadBarrierOption read_barrier_option) {
DataType::Type type = DataType::Type::kReference;
Register out_reg = RegisterFrom(out, type);
if (read_barrier_option == kWithReadBarrier) {
CHECK(kEmitCompilerReadBarrier);
if (kUseBakerReadBarrier) {
// Load with fast path based Baker's read barrier.
// /* HeapReference<Object> */ out = *(out + offset)
codegen_->GenerateFieldLoadWithBakerReadBarrier(instruction,
out,
out_reg,
offset,
maybe_temp,
/* needs_null_check */ false,
/* use_load_acquire */ false);
} else {
// Load with slow path based read barrier.
// Save the value of `out` into `maybe_temp` before overwriting it
// in the following move operation, as we will need it for the
// read barrier below.
Register temp_reg = RegisterFrom(maybe_temp, type);
__ Mov(temp_reg, out_reg);
// /* HeapReference<Object> */ out = *(out + offset)
__ Ldr(out_reg, HeapOperand(out_reg, offset));
codegen_->GenerateReadBarrierSlow(instruction, out, out, maybe_temp, offset);
}
} else {
// Plain load with no read barrier.
// /* HeapReference<Object> */ out = *(out + offset)
__ Ldr(out_reg, HeapOperand(out_reg, offset));
GetAssembler()->MaybeUnpoisonHeapReference(out_reg);
}
}
void InstructionCodeGeneratorARM64::GenerateReferenceLoadTwoRegisters(
HInstruction* instruction,
Location out,
Location obj,
uint32_t offset,
Location maybe_temp,
ReadBarrierOption read_barrier_option) {
DataType::Type type = DataType::Type::kReference;
Register out_reg = RegisterFrom(out, type);
Register obj_reg = RegisterFrom(obj, type);
if (read_barrier_option == kWithReadBarrier) {
CHECK(kEmitCompilerReadBarrier);
if (kUseBakerReadBarrier) {
// Load with fast path based Baker's read barrier.
// /* HeapReference<Object> */ out = *(obj + offset)
codegen_->GenerateFieldLoadWithBakerReadBarrier(instruction,
out,
obj_reg,
offset,
maybe_temp,
/* needs_null_check */ false,
/* use_load_acquire */ false);
} else {
// Load with slow path based read barrier.
// /* HeapReference<Object> */ out = *(obj + offset)
__ Ldr(out_reg, HeapOperand(obj_reg, offset));
codegen_->GenerateReadBarrierSlow(instruction, out, out, obj, offset);
}
} else {
// Plain load with no read barrier.
// /* HeapReference<Object> */ out = *(obj + offset)
__ Ldr(out_reg, HeapOperand(obj_reg, offset));
GetAssembler()->MaybeUnpoisonHeapReference(out_reg);
}
}
void CodeGeneratorARM64::GenerateGcRootFieldLoad(
HInstruction* instruction,
Location root,
Register obj,
uint32_t offset,
vixl::aarch64::Label* fixup_label,
ReadBarrierOption read_barrier_option) {
DCHECK(fixup_label == nullptr || offset == 0u);
Register root_reg = RegisterFrom(root, DataType::Type::kReference);
if (read_barrier_option == kWithReadBarrier) {
DCHECK(kEmitCompilerReadBarrier);
if (kUseBakerReadBarrier) {
// Fast path implementation of art::ReadBarrier::BarrierForRoot when
// Baker's read barrier are used.
if (kBakerReadBarrierLinkTimeThunksEnableForGcRoots &&
!Runtime::Current()->UseJitCompilation()) {
// Query `art::Thread::Current()->GetIsGcMarking()` (stored in
// the Marking Register) to decide whether we need to enter
// the slow path to mark the GC root.
//
// We use link-time generated thunks for the slow path. That thunk
// checks the reference and jumps to the entrypoint if needed.
//
// lr = &return_address;
// GcRoot<mirror::Object> root = *(obj+offset); // Original reference load.
// if (mr) { // Thread::Current()->GetIsGcMarking()
// goto gc_root_thunk<root_reg>(lr)
// }
// return_address:
UseScratchRegisterScope temps(GetVIXLAssembler());
DCHECK(temps.IsAvailable(ip0));
DCHECK(temps.IsAvailable(ip1));
temps.Exclude(ip0, ip1);
uint32_t custom_data = EncodeBakerReadBarrierGcRootData(root_reg.GetCode());
vixl::aarch64::Label* cbnz_label = NewBakerReadBarrierPatch(custom_data);
EmissionCheckScope guard(GetVIXLAssembler(), 3 * vixl::aarch64::kInstructionSize);
vixl::aarch64::Label return_address;
__ adr(lr, &return_address);
if (fixup_label != nullptr) {
__ Bind(fixup_label);
}
static_assert(BAKER_MARK_INTROSPECTION_GC_ROOT_LDR_OFFSET == -8,
"GC root LDR must be 2 instruction (8B) before the return address label.");
__ ldr(root_reg, MemOperand(obj.X(), offset));
__ Bind(cbnz_label);
__ cbnz(mr, static_cast<int64_t>(0)); // Placeholder, patched at link-time.
__ Bind(&return_address);
} else {
// Query `art::Thread::Current()->GetIsGcMarking()` (stored in
// the Marking Register) to decide whether we need to enter
// the slow path to mark the GC root.
//
// GcRoot<mirror::Object> root = *(obj+offset); // Original reference load.
// if (mr) { // Thread::Current()->GetIsGcMarking()
// // Slow path.
// entrypoint = Thread::Current()->pReadBarrierMarkReg ## root.reg()
// root = entrypoint(root); // root = ReadBarrier::Mark(root); // Entry point call.
// }
// Slow path marking the GC root `root`. The entrypoint will
// be loaded by the slow path code.
SlowPathCodeARM64* slow_path =
new (GetScopedAllocator()) ReadBarrierMarkSlowPathARM64(instruction, root);
AddSlowPath(slow_path);
// /* GcRoot<mirror::Object> */ root = *(obj + offset)
if (fixup_label == nullptr) {
__ Ldr(root_reg, MemOperand(obj, offset));
} else {
EmitLdrOffsetPlaceholder(fixup_label, root_reg, obj);
}
static_assert(
sizeof(mirror::CompressedReference<mirror::Object>) == sizeof(GcRoot<mirror::Object>),
"art::mirror::CompressedReference<mirror::Object> and art::GcRoot<mirror::Object> "
"have different sizes.");
static_assert(sizeof(mirror::CompressedReference<mirror::Object>) == sizeof(int32_t),
"art::mirror::CompressedReference<mirror::Object> and int32_t "
"have different sizes.");
__ Cbnz(mr, slow_path->GetEntryLabel());
__ Bind(slow_path->GetExitLabel());
}
} else {
// GC root loaded through a slow path for read barriers other
// than Baker's.
// /* GcRoot<mirror::Object>* */ root = obj + offset
if (fixup_label == nullptr) {
__ Add(root_reg.X(), obj.X(), offset);
} else {
EmitAddPlaceholder(fixup_label, root_reg.X(), obj.X());
}
// /* mirror::Object* */ root = root->Read()
GenerateReadBarrierForRootSlow(instruction, root, root);
}
} else {
// Plain GC root load with no read barrier.
// /* GcRoot<mirror::Object> */ root = *(obj + offset)
if (fixup_label == nullptr) {
__ Ldr(root_reg, MemOperand(obj, offset));
} else {
EmitLdrOffsetPlaceholder(fixup_label, root_reg, obj.X());
}
// Note that GC roots are not affected by heap poisoning, thus we
// do not have to unpoison `root_reg` here.
}
MaybeGenerateMarkingRegisterCheck(/* code */ __LINE__);
}
void CodeGeneratorARM64::GenerateFieldLoadWithBakerReadBarrier(HInstruction* instruction,
Location ref,
Register obj,
uint32_t offset,
Location maybe_temp,
bool needs_null_check,
bool use_load_acquire) {
DCHECK(kEmitCompilerReadBarrier);
DCHECK(kUseBakerReadBarrier);
if (kBakerReadBarrierLinkTimeThunksEnableForFields &&
!use_load_acquire &&
!Runtime::Current()->UseJitCompilation()) {
// Query `art::Thread::Current()->GetIsGcMarking()` (stored in the
// Marking Register) to decide whether we need to enter the slow
// path to mark the reference. Then, in the slow path, check the
// gray bit in the lock word of the reference's holder (`obj`) to
// decide whether to mark `ref` or not.
//
// We use link-time generated thunks for the slow path. That thunk checks
// the holder and jumps to the entrypoint if needed. If the holder is not
// gray, it creates a fake dependency and returns to the LDR instruction.
//
// lr = &gray_return_address;
// if (mr) { // Thread::Current()->GetIsGcMarking()
// goto field_thunk<holder_reg, base_reg>(lr)
// }
// not_gray_return_address:
// // Original reference load. If the offset is too large to fit
// // into LDR, we use an adjusted base register here.
// HeapReference<mirror::Object> reference = *(obj+offset);
// gray_return_address:
DCHECK_ALIGNED(offset, sizeof(mirror::HeapReference<mirror::Object>));
Register base = obj;
if (offset >= kReferenceLoadMinFarOffset) {
DCHECK(maybe_temp.IsRegister());
base = WRegisterFrom(maybe_temp);
static_assert(IsPowerOfTwo(kReferenceLoadMinFarOffset), "Expecting a power of 2.");
__ Add(base, obj, Operand(offset & ~(kReferenceLoadMinFarOffset - 1u)));
offset &= (kReferenceLoadMinFarOffset - 1u);
}
UseScratchRegisterScope temps(GetVIXLAssembler());
DCHECK(temps.IsAvailable(ip0));
DCHECK(temps.IsAvailable(ip1));
temps.Exclude(ip0, ip1);
uint32_t custom_data = EncodeBakerReadBarrierFieldData(base.GetCode(), obj.GetCode());
vixl::aarch64::Label* cbnz_label = NewBakerReadBarrierPatch(custom_data);
{
EmissionCheckScope guard(GetVIXLAssembler(),
(kPoisonHeapReferences ? 4u : 3u) * vixl::aarch64::kInstructionSize);
vixl::aarch64::Label return_address;
__ adr(lr, &return_address);
__ Bind(cbnz_label);
__ cbnz(mr, static_cast<int64_t>(0)); // Placeholder, patched at link-time.
static_assert(BAKER_MARK_INTROSPECTION_FIELD_LDR_OFFSET == (kPoisonHeapReferences ? -8 : -4),
"Field LDR must be 1 instruction (4B) before the return address label; "
" 2 instructions (8B) for heap poisoning.");
Register ref_reg = RegisterFrom(ref, DataType::Type::kReference);
__ ldr(ref_reg, MemOperand(base.X(), offset));
if (needs_null_check) {
MaybeRecordImplicitNullCheck(instruction);
}
GetAssembler()->MaybeUnpoisonHeapReference(ref_reg);
__ Bind(&return_address);
}
MaybeGenerateMarkingRegisterCheck(/* code */ __LINE__, /* temp_loc */ LocationFrom(ip1));
return;
}
// /* HeapReference<Object> */ ref = *(obj + offset)
Register temp = WRegisterFrom(maybe_temp);
Location no_index = Location::NoLocation();
size_t no_scale_factor = 0u;
GenerateReferenceLoadWithBakerReadBarrier(instruction,
ref,
obj,
offset,
no_index,
no_scale_factor,
temp,
needs_null_check,
use_load_acquire);
}
void CodeGeneratorARM64::GenerateArrayLoadWithBakerReadBarrier(HInstruction* instruction,
Location ref,
Register obj,
uint32_t data_offset,
Location index,
Register temp,
bool needs_null_check) {
DCHECK(kEmitCompilerReadBarrier);
DCHECK(kUseBakerReadBarrier);
static_assert(
sizeof(mirror::HeapReference<mirror::Object>) == sizeof(int32_t),
"art::mirror::HeapReference<art::mirror::Object> and int32_t have different sizes.");
size_t scale_factor = DataType::SizeShift(DataType::Type::kReference);
if (kBakerReadBarrierLinkTimeThunksEnableForArrays &&
!Runtime::Current()->UseJitCompilation()) {
// Query `art::Thread::Current()->GetIsGcMarking()` (stored in the
// Marking Register) to decide whether we need to enter the slow
// path to mark the reference. Then, in the slow path, check the
// gray bit in the lock word of the reference's holder (`obj`) to
// decide whether to mark `ref` or not.
//
// We use link-time generated thunks for the slow path. That thunk checks
// the holder and jumps to the entrypoint if needed. If the holder is not
// gray, it creates a fake dependency and returns to the LDR instruction.
//
// lr = &gray_return_address;
// if (mr) { // Thread::Current()->GetIsGcMarking()
// goto array_thunk<base_reg>(lr)
// }
// not_gray_return_address:
// // Original reference load. If the offset is too large to fit
// // into LDR, we use an adjusted base register here.
// HeapReference<mirror::Object> reference = data[index];
// gray_return_address:
DCHECK(index.IsValid());
Register index_reg = RegisterFrom(index, DataType::Type::kInt32);
Register ref_reg = RegisterFrom(ref, DataType::Type::kReference);
UseScratchRegisterScope temps(GetVIXLAssembler());
DCHECK(temps.IsAvailable(ip0));
DCHECK(temps.IsAvailable(ip1));
temps.Exclude(ip0, ip1);
uint32_t custom_data = EncodeBakerReadBarrierArrayData(temp.GetCode());
vixl::aarch64::Label* cbnz_label = NewBakerReadBarrierPatch(custom_data);
__ Add(temp.X(), obj.X(), Operand(data_offset));
{
EmissionCheckScope guard(GetVIXLAssembler(),
(kPoisonHeapReferences ? 4u : 3u) * vixl::aarch64::kInstructionSize);
vixl::aarch64::Label return_address;
__ adr(lr, &return_address);
__ Bind(cbnz_label);
__ cbnz(mr, static_cast<int64_t>(0)); // Placeholder, patched at link-time.
static_assert(BAKER_MARK_INTROSPECTION_ARRAY_LDR_OFFSET == (kPoisonHeapReferences ? -8 : -4),
"Array LDR must be 1 instruction (4B) before the return address label; "
" 2 instructions (8B) for heap poisoning.");
__ ldr(ref_reg, MemOperand(temp.X(), index_reg.X(), LSL, scale_factor));
DCHECK(!needs_null_check); // The thunk cannot handle the null check.
GetAssembler()->MaybeUnpoisonHeapReference(ref_reg);
__ Bind(&return_address);
}
MaybeGenerateMarkingRegisterCheck(/* code */ __LINE__, /* temp_loc */ LocationFrom(ip1));
return;
}
// Array cells are never volatile variables, therefore array loads
// never use Load-Acquire instructions on ARM64.
const bool use_load_acquire = false;
// /* HeapReference<Object> */ ref =
// *(obj + data_offset + index * sizeof(HeapReference<Object>))
GenerateReferenceLoadWithBakerReadBarrier(instruction,
ref,
obj,
data_offset,
index,
scale_factor,
temp,
needs_null_check,
use_load_acquire);
}
void CodeGeneratorARM64::GenerateReferenceLoadWithBakerReadBarrier(HInstruction* instruction,
Location ref,
Register obj,
uint32_t offset,
Location index,
size_t scale_factor,
Register temp,
bool needs_null_check,
bool use_load_acquire) {
DCHECK(kEmitCompilerReadBarrier);
DCHECK(kUseBakerReadBarrier);
// If we are emitting an array load, we should not be using a
// Load Acquire instruction. In other words:
// `instruction->IsArrayGet()` => `!use_load_acquire`.
DCHECK(!instruction->IsArrayGet() || !use_load_acquire);
// Query `art::Thread::Current()->GetIsGcMarking()` (stored in the
// Marking Register) to decide whether we need to enter the slow
// path to mark the reference. Then, in the slow path, check the
// gray bit in the lock word of the reference's holder (`obj`) to
// decide whether to mark `ref` or not.
//
// if (mr) { // Thread::Current()->GetIsGcMarking()
// // Slow path.
// uint32_t rb_state = Lockword(obj->monitor_).ReadBarrierState();
// lfence; // Load fence or artificial data dependency to prevent load-load reordering
// HeapReference<mirror::Object> ref = *src; // Original reference load.
// bool is_gray = (rb_state == ReadBarrier::GrayState());
// if (is_gray) {
// entrypoint = Thread::Current()->pReadBarrierMarkReg ## root.reg()
// ref = entrypoint(ref); // ref = ReadBarrier::Mark(ref); // Runtime entry point call.
// }
// } else {
// HeapReference<mirror::Object> ref = *src; // Original reference load.
// }
// Slow path marking the object `ref` when the GC is marking. The
// entrypoint will be loaded by the slow path code.
SlowPathCodeARM64* slow_path =
new (GetScopedAllocator()) LoadReferenceWithBakerReadBarrierSlowPathARM64(
instruction,
ref,
obj,
offset,
index,
scale_factor,
needs_null_check,
use_load_acquire,
temp);
AddSlowPath(slow_path);
__ Cbnz(mr, slow_path->GetEntryLabel());
// Fast path: the GC is not marking: just load the reference.
GenerateRawReferenceLoad(
instruction, ref, obj, offset, index, scale_factor, needs_null_check, use_load_acquire);
__ Bind(slow_path->GetExitLabel());
MaybeGenerateMarkingRegisterCheck(/* code */ __LINE__);
}
void CodeGeneratorARM64::UpdateReferenceFieldWithBakerReadBarrier(HInstruction* instruction,
Location ref,
Register obj,
Location field_offset,
Register temp,
bool needs_null_check,
bool use_load_acquire) {
DCHECK(kEmitCompilerReadBarrier);
DCHECK(kUseBakerReadBarrier);
// If we are emitting an array load, we should not be using a
// Load Acquire instruction. In other words:
// `instruction->IsArrayGet()` => `!use_load_acquire`.
DCHECK(!instruction->IsArrayGet() || !use_load_acquire);
// Query `art::Thread::Current()->GetIsGcMarking()` (stored in the
// Marking Register) to decide whether we need to enter the slow
// path to update the reference field within `obj`. Then, in the
// slow path, check the gray bit in the lock word of the reference's
// holder (`obj`) to decide whether to mark `ref` and update the
// field or not.
//
// if (mr) { // Thread::Current()->GetIsGcMarking()
// // Slow path.
// uint32_t rb_state = Lockword(obj->monitor_).ReadBarrierState();
// lfence; // Load fence or artificial data dependency to prevent load-load reordering
// HeapReference<mirror::Object> ref = *(obj + field_offset); // Reference load.
// bool is_gray = (rb_state == ReadBarrier::GrayState());
// if (is_gray) {
// old_ref = ref;
// entrypoint = Thread::Current()->pReadBarrierMarkReg ## root.reg()
// ref = entrypoint(ref); // ref = ReadBarrier::Mark(ref); // Runtime entry point call.
// compareAndSwapObject(obj, field_offset, old_ref, ref);
// }
// }
// Slow path updating the object reference at address `obj + field_offset`
// when the GC is marking. The entrypoint will be loaded by the slow path code.
SlowPathCodeARM64* slow_path =
new (GetScopedAllocator()) LoadReferenceWithBakerReadBarrierAndUpdateFieldSlowPathARM64(
instruction,
ref,
obj,
/* offset */ 0u,
/* index */ field_offset,
/* scale_factor */ 0u /* "times 1" */,
needs_null_check,
use_load_acquire,
temp);
AddSlowPath(slow_path);
__ Cbnz(mr, slow_path->GetEntryLabel());
// Fast path: the GC is not marking: nothing to do (the field is
// up-to-date, and we don't need to load the reference).
__ Bind(slow_path->GetExitLabel());
MaybeGenerateMarkingRegisterCheck(/* code */ __LINE__);
}
void CodeGeneratorARM64::GenerateRawReferenceLoad(HInstruction* instruction,
Location ref,
Register obj,
uint32_t offset,
Location index,
size_t scale_factor,
bool needs_null_check,
bool use_load_acquire) {
DCHECK(obj.IsW());
DataType::Type type = DataType::Type::kReference;
Register ref_reg = RegisterFrom(ref, type);
// If needed, vixl::EmissionCheckScope guards are used to ensure
// that no pools are emitted between the load (macro) instruction
// and MaybeRecordImplicitNullCheck.
if (index.IsValid()) {
// Load types involving an "index": ArrayGet,
// UnsafeGetObject/UnsafeGetObjectVolatile and UnsafeCASObject
// intrinsics.
if (use_load_acquire) {
// UnsafeGetObjectVolatile intrinsic case.
// Register `index` is not an index in an object array, but an
// offset to an object reference field within object `obj`.
DCHECK(instruction->IsInvoke()) << instruction->DebugName();
DCHECK(instruction->GetLocations()->Intrinsified());
DCHECK(instruction->AsInvoke()->GetIntrinsic() == Intrinsics::kUnsafeGetObjectVolatile)
<< instruction->AsInvoke()->GetIntrinsic();
DCHECK_EQ(offset, 0u);
DCHECK_EQ(scale_factor, 0u);
DCHECK_EQ(needs_null_check, false);
// /* HeapReference<mirror::Object> */ ref = *(obj + index)
MemOperand field = HeapOperand(obj, XRegisterFrom(index));
LoadAcquire(instruction, ref_reg, field, /* needs_null_check */ false);
} else {
// ArrayGet and UnsafeGetObject and UnsafeCASObject intrinsics cases.
// /* HeapReference<mirror::Object> */ ref = *(obj + offset + (index << scale_factor))
if (index.IsConstant()) {
uint32_t computed_offset = offset + (Int64ConstantFrom(index) << scale_factor);
EmissionCheckScope guard(GetVIXLAssembler(), kMaxMacroInstructionSizeInBytes);
Load(type, ref_reg, HeapOperand(obj, computed_offset));
if (needs_null_check) {
MaybeRecordImplicitNullCheck(instruction);
}
} else {
UseScratchRegisterScope temps(GetVIXLAssembler());
Register temp = temps.AcquireW();
__ Add(temp, obj, offset);
{
EmissionCheckScope guard(GetVIXLAssembler(), kMaxMacroInstructionSizeInBytes);
Load(type, ref_reg, HeapOperand(temp, XRegisterFrom(index), LSL, scale_factor));
if (needs_null_check) {
MaybeRecordImplicitNullCheck(instruction);
}
}
}
}
} else {
// /* HeapReference<mirror::Object> */ ref = *(obj + offset)
MemOperand field = HeapOperand(obj, offset);
if (use_load_acquire) {
// Implicit null checks are handled by CodeGeneratorARM64::LoadAcquire.
LoadAcquire(instruction, ref_reg, field, needs_null_check);
} else {
EmissionCheckScope guard(GetVIXLAssembler(), kMaxMacroInstructionSizeInBytes);
Load(type, ref_reg, field);
if (needs_null_check) {
MaybeRecordImplicitNullCheck(instruction);
}
}
}
// Object* ref = ref_addr->AsMirrorPtr()
GetAssembler()->MaybeUnpoisonHeapReference(ref_reg);
}
void CodeGeneratorARM64::MaybeGenerateMarkingRegisterCheck(int code, Location temp_loc) {
// The following condition is a compile-time one, so it does not have a run-time cost.
if (kEmitCompilerReadBarrier && kUseBakerReadBarrier && kIsDebugBuild) {
// The following condition is a run-time one; it is executed after the
// previous compile-time test, to avoid penalizing non-debug builds.
if (GetCompilerOptions().EmitRunTimeChecksInDebugMode()) {
UseScratchRegisterScope temps(GetVIXLAssembler());
Register temp = temp_loc.IsValid() ? WRegisterFrom(temp_loc) : temps.AcquireW();
GetAssembler()->GenerateMarkingRegisterCheck(temp, code);
}
}
}
void CodeGeneratorARM64::GenerateReadBarrierSlow(HInstruction* instruction,
Location out,
Location ref,
Location obj,
uint32_t offset,
Location index) {
DCHECK(kEmitCompilerReadBarrier);
// Insert a slow path based read barrier *after* the reference load.
//
// If heap poisoning is enabled, the unpoisoning of the loaded
// reference will be carried out by the runtime within the slow
// path.
//
// Note that `ref` currently does not get unpoisoned (when heap
// poisoning is enabled), which is alright as the `ref` argument is
// not used by the artReadBarrierSlow entry point.
//
// TODO: Unpoison `ref` when it is used by artReadBarrierSlow.
SlowPathCodeARM64* slow_path = new (GetScopedAllocator())
ReadBarrierForHeapReferenceSlowPathARM64(instruction, out, ref, obj, offset, index);
AddSlowPath(slow_path);
__ B(slow_path->GetEntryLabel());
__ Bind(slow_path->GetExitLabel());
}
void CodeGeneratorARM64::MaybeGenerateReadBarrierSlow(HInstruction* instruction,
Location out,
Location ref,
Location obj,
uint32_t offset,
Location index) {
if (kEmitCompilerReadBarrier) {
// Baker's read barriers shall be handled by the fast path
// (CodeGeneratorARM64::GenerateReferenceLoadWithBakerReadBarrier).
DCHECK(!kUseBakerReadBarrier);
// If heap poisoning is enabled, unpoisoning will be taken care of
// by the runtime within the slow path.
GenerateReadBarrierSlow(instruction, out, ref, obj, offset, index);
} else if (kPoisonHeapReferences) {
GetAssembler()->UnpoisonHeapReference(WRegisterFrom(out));
}
}
void CodeGeneratorARM64::GenerateReadBarrierForRootSlow(HInstruction* instruction,
Location out,
Location root) {
DCHECK(kEmitCompilerReadBarrier);
// Insert a slow path based read barrier *after* the GC root load.
//
// Note that GC roots are not affected by heap poisoning, so we do
// not need to do anything special for this here.
SlowPathCodeARM64* slow_path =
new (GetScopedAllocator()) ReadBarrierForRootSlowPathARM64(instruction, out, root);
AddSlowPath(slow_path);
__ B(slow_path->GetEntryLabel());
__ Bind(slow_path->GetExitLabel());
}
void LocationsBuilderARM64::VisitClassTableGet(HClassTableGet* instruction) {
LocationSummary* locations =
new (GetGraph()->GetAllocator()) LocationSummary(instruction, LocationSummary::kNoCall);
locations->SetInAt(0, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister());
}
void InstructionCodeGeneratorARM64::VisitClassTableGet(HClassTableGet* instruction) {
LocationSummary* locations = instruction->GetLocations();
if (instruction->GetTableKind() == HClassTableGet::TableKind::kVTable) {
uint32_t method_offset = mirror::Class::EmbeddedVTableEntryOffset(
instruction->GetIndex(), kArm64PointerSize).SizeValue();
__ Ldr(XRegisterFrom(locations->Out()),
MemOperand(XRegisterFrom(locations->InAt(0)), method_offset));
} else {
uint32_t method_offset = static_cast<uint32_t>(ImTable::OffsetOfElement(
instruction->GetIndex(), kArm64PointerSize));
__ Ldr(XRegisterFrom(locations->Out()), MemOperand(XRegisterFrom(locations->InAt(0)),
mirror::Class::ImtPtrOffset(kArm64PointerSize).Uint32Value()));
__ Ldr(XRegisterFrom(locations->Out()),
MemOperand(XRegisterFrom(locations->Out()), method_offset));
}
}
static void PatchJitRootUse(uint8_t* code,
const uint8_t* roots_data,
vixl::aarch64::Literal<uint32_t>* literal,
uint64_t index_in_table) {
uint32_t literal_offset = literal->GetOffset();
uintptr_t address =
reinterpret_cast<uintptr_t>(roots_data) + index_in_table * sizeof(GcRoot<mirror::Object>);
uint8_t* data = code + literal_offset;
reinterpret_cast<uint32_t*>(data)[0] = dchecked_integral_cast<uint32_t>(address);
}
void CodeGeneratorARM64::EmitJitRootPatches(uint8_t* code, const uint8_t* roots_data) {
for (const auto& entry : jit_string_patches_) {
const StringReference& string_reference = entry.first;
vixl::aarch64::Literal<uint32_t>* table_entry_literal = entry.second;
uint64_t index_in_table = GetJitStringRootIndex(string_reference);
PatchJitRootUse(code, roots_data, table_entry_literal, index_in_table);
}
for (const auto& entry : jit_class_patches_) {
const TypeReference& type_reference = entry.first;
vixl::aarch64::Literal<uint32_t>* table_entry_literal = entry.second;
uint64_t index_in_table = GetJitClassRootIndex(type_reference);
PatchJitRootUse(code, roots_data, table_entry_literal, index_in_table);
}
}
#undef __
#undef QUICK_ENTRY_POINT
#define __ assembler.GetVIXLAssembler()->
static void EmitGrayCheckAndFastPath(arm64::Arm64Assembler& assembler,
vixl::aarch64::Register base_reg,
vixl::aarch64::MemOperand& lock_word,
vixl::aarch64::Label* slow_path,
vixl::aarch64::Label* throw_npe = nullptr) {
// Load the lock word containing the rb_state.
__ Ldr(ip0.W(), lock_word);
// Given the numeric representation, it's enough to check the low bit of the rb_state.
static_assert(ReadBarrier::WhiteState() == 0, "Expecting white to have value 0");
static_assert(ReadBarrier::GrayState() == 1, "Expecting gray to have value 1");
__ Tbnz(ip0.W(), LockWord::kReadBarrierStateShift, slow_path);
static_assert(
BAKER_MARK_INTROSPECTION_ARRAY_LDR_OFFSET == BAKER_MARK_INTROSPECTION_FIELD_LDR_OFFSET,
"Field and array LDR offsets must be the same to reuse the same code.");
// To throw NPE, we return to the fast path; the artificial dependence below does not matter.
if (throw_npe != nullptr) {
__ Bind(throw_npe);
}
// Adjust the return address back to the LDR (1 instruction; 2 for heap poisoning).
static_assert(BAKER_MARK_INTROSPECTION_FIELD_LDR_OFFSET == (kPoisonHeapReferences ? -8 : -4),
"Field LDR must be 1 instruction (4B) before the return address label; "
" 2 instructions (8B) for heap poisoning.");
__ Add(lr, lr, BAKER_MARK_INTROSPECTION_FIELD_LDR_OFFSET);
// Introduce a dependency on the lock_word including rb_state,
// to prevent load-load reordering, and without using
// a memory barrier (which would be more expensive).
__ Add(base_reg, base_reg, Operand(ip0, LSR, 32));
__ Br(lr); // And return back to the function.
// Note: The fake dependency is unnecessary for the slow path.
}
// Load the read barrier introspection entrypoint in register `entrypoint`.
static void LoadReadBarrierMarkIntrospectionEntrypoint(arm64::Arm64Assembler& assembler,
vixl::aarch64::Register entrypoint) {
// entrypoint = Thread::Current()->pReadBarrierMarkReg16, i.e. pReadBarrierMarkIntrospection.
DCHECK_EQ(ip0.GetCode(), 16u);
const int32_t entry_point_offset =
Thread::ReadBarrierMarkEntryPointsOffset<kArm64PointerSize>(ip0.GetCode());
__ Ldr(entrypoint, MemOperand(tr, entry_point_offset));
}
void CodeGeneratorARM64::CompileBakerReadBarrierThunk(Arm64Assembler& assembler,
uint32_t encoded_data,
/*out*/ std::string* debug_name) {
BakerReadBarrierKind kind = BakerReadBarrierKindField::Decode(encoded_data);
switch (kind) {
case BakerReadBarrierKind::kField: {
auto base_reg =
Register::GetXRegFromCode(BakerReadBarrierFirstRegField::Decode(encoded_data));
CheckValidReg(base_reg.GetCode());
auto holder_reg =
Register::GetXRegFromCode(BakerReadBarrierSecondRegField::Decode(encoded_data));
CheckValidReg(holder_reg.GetCode());
UseScratchRegisterScope temps(assembler.GetVIXLAssembler());
temps.Exclude(ip0, ip1);
// If base_reg differs from holder_reg, the offset was too large and we must have emitted
// an explicit null check before the load. Otherwise, for implicit null checks, we need to
// null-check the holder as we do not necessarily do that check before going to the thunk.
vixl::aarch64::Label throw_npe_label;
vixl::aarch64::Label* throw_npe = nullptr;
if (GetCompilerOptions().GetImplicitNullChecks() && holder_reg.Is(base_reg)) {
throw_npe = &throw_npe_label;
__ Cbz(holder_reg.W(), throw_npe);
}
// Check if the holder is gray and, if not, add fake dependency to the base register
// and return to the LDR instruction to load the reference. Otherwise, use introspection
// to load the reference and call the entrypoint that performs further checks on the
// reference and marks it if needed.
vixl::aarch64::Label slow_path;
MemOperand lock_word(holder_reg, mirror::Object::MonitorOffset().Int32Value());
EmitGrayCheckAndFastPath(assembler, base_reg, lock_word, &slow_path, throw_npe);
__ Bind(&slow_path);
MemOperand ldr_address(lr, BAKER_MARK_INTROSPECTION_FIELD_LDR_OFFSET);
__ Ldr(ip0.W(), ldr_address); // Load the LDR (immediate) unsigned offset.
LoadReadBarrierMarkIntrospectionEntrypoint(assembler, ip1);
__ Ubfx(ip0.W(), ip0.W(), 10, 12); // Extract the offset.
__ Ldr(ip0.W(), MemOperand(base_reg, ip0, LSL, 2)); // Load the reference.
// Do not unpoison. With heap poisoning enabled, the entrypoint expects a poisoned reference.
__ Br(ip1); // Jump to the entrypoint.
break;
}
case BakerReadBarrierKind::kArray: {
auto base_reg =
Register::GetXRegFromCode(BakerReadBarrierFirstRegField::Decode(encoded_data));
CheckValidReg(base_reg.GetCode());
DCHECK_EQ(kBakerReadBarrierInvalidEncodedReg,
BakerReadBarrierSecondRegField::Decode(encoded_data));
UseScratchRegisterScope temps(assembler.GetVIXLAssembler());
temps.Exclude(ip0, ip1);
vixl::aarch64::Label slow_path;
int32_t data_offset =
mirror::Array::DataOffset(Primitive::ComponentSize(Primitive::kPrimNot)).Int32Value();
MemOperand lock_word(base_reg, mirror::Object::MonitorOffset().Int32Value() - data_offset);
DCHECK_LT(lock_word.GetOffset(), 0);
EmitGrayCheckAndFastPath(assembler, base_reg, lock_word, &slow_path);
__ Bind(&slow_path);
MemOperand ldr_address(lr, BAKER_MARK_INTROSPECTION_ARRAY_LDR_OFFSET);
__ Ldr(ip0.W(), ldr_address); // Load the LDR (register) unsigned offset.
LoadReadBarrierMarkIntrospectionEntrypoint(assembler, ip1);
__ Ubfx(ip0, ip0, 16, 6); // Extract the index register, plus 32 (bit 21 is set).
__ Bfi(ip1, ip0, 3, 6); // Insert ip0 to the entrypoint address to create
// a switch case target based on the index register.
__ Mov(ip0, base_reg); // Move the base register to ip0.
__ Br(ip1); // Jump to the entrypoint's array switch case.
break;
}
case BakerReadBarrierKind::kGcRoot: {
// Check if the reference needs to be marked and if so (i.e. not null, not marked yet
// and it does not have a forwarding address), call the correct introspection entrypoint;
// otherwise return the reference (or the extracted forwarding address).
// There is no gray bit check for GC roots.
auto root_reg =
Register::GetWRegFromCode(BakerReadBarrierFirstRegField::Decode(encoded_data));
CheckValidReg(root_reg.GetCode());
DCHECK_EQ(kBakerReadBarrierInvalidEncodedReg,
BakerReadBarrierSecondRegField::Decode(encoded_data));
UseScratchRegisterScope temps(assembler.GetVIXLAssembler());
temps.Exclude(ip0, ip1);
vixl::aarch64::Label return_label, not_marked, forwarding_address;
__ Cbz(root_reg, &return_label);
MemOperand lock_word(root_reg.X(), mirror::Object::MonitorOffset().Int32Value());
__ Ldr(ip0.W(), lock_word);
__ Tbz(ip0.W(), LockWord::kMarkBitStateShift, &not_marked);
__ Bind(&return_label);
__ Br(lr);
__ Bind(&not_marked);
__ Tst(ip0.W(), Operand(ip0.W(), LSL, 1));
__ B(&forwarding_address, mi);
LoadReadBarrierMarkIntrospectionEntrypoint(assembler, ip1);
// Adjust the art_quick_read_barrier_mark_introspection address in IP1 to
// art_quick_read_barrier_mark_introspection_gc_roots.
__ Add(ip1, ip1, Operand(BAKER_MARK_INTROSPECTION_GC_ROOT_ENTRYPOINT_OFFSET));
__ Mov(ip0.W(), root_reg);
__ Br(ip1);
__ Bind(&forwarding_address);
__ Lsl(root_reg, ip0.W(), LockWord::kForwardingAddressShift);
__ Br(lr);
break;
}
default:
LOG(FATAL) << "Unexpected kind: " << static_cast<uint32_t>(kind);
UNREACHABLE();
}
if (GetCompilerOptions().GenerateAnyDebugInfo()) {
std::ostringstream oss;
oss << "BakerReadBarrierThunk";
switch (kind) {
case BakerReadBarrierKind::kField:
oss << "Field_r" << BakerReadBarrierFirstRegField::Decode(encoded_data)
<< "_r" << BakerReadBarrierSecondRegField::Decode(encoded_data);
break;
case BakerReadBarrierKind::kArray:
oss << "Array_r" << BakerReadBarrierFirstRegField::Decode(encoded_data);
DCHECK_EQ(kBakerReadBarrierInvalidEncodedReg,
BakerReadBarrierSecondRegField::Decode(encoded_data));
break;
case BakerReadBarrierKind::kGcRoot:
oss << "GcRoot_r" << BakerReadBarrierFirstRegField::Decode(encoded_data);
DCHECK_EQ(kBakerReadBarrierInvalidEncodedReg,
BakerReadBarrierSecondRegField::Decode(encoded_data));
break;
}
*debug_name = oss.str();
}
}
#undef __
} // namespace arm64
} // namespace art