Gitiles
Code Review Sign In
gerrit-public.fairphone.software / fp2-dev / platform / external / v8 / 69a99ed0b2b2ef69d393c371b03db3a98aaf880e / . / src / mips / macro-assembler-mips.cc
blob: c7f727bef604e1e0eff71ff0987b00b57f5d2c56 [file] [log] [blame]
// Copyright 2011 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following
// disclaimer in the documentation and/or other materials provided
// with the distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#include <limits.h> // For LONG_MIN, LONG_MAX.
#include "v8.h"
#if defined(V8_TARGET_ARCH_MIPS)
#include "bootstrapper.h"
#include "codegen.h"
#include "debug.h"
#include "runtime.h"
namespace v8 {
namespace internal {
MacroAssembler::MacroAssembler(Isolate* arg_isolate, void* buffer, int size)
: Assembler(arg_isolate, buffer, size),
generating_stub_(false),
allow_stub_calls_(true) {
if (isolate() != NULL) {
code_object_ = Handle<Object>(isolate()->heap()->undefined_value(),
isolate());
}
}
void MacroAssembler::LoadRoot(Register destination,
Heap::RootListIndex index) {
lw(destination, MemOperand(s6, index << kPointerSizeLog2));
}
void MacroAssembler::LoadRoot(Register destination,
Heap::RootListIndex index,
Condition cond,
Register src1, const Operand& src2) {
Branch(2, NegateCondition(cond), src1, src2);
lw(destination, MemOperand(s6, index << kPointerSizeLog2));
}
void MacroAssembler::StoreRoot(Register source,
Heap::RootListIndex index) {
sw(source, MemOperand(s6, index << kPointerSizeLog2));
}
void MacroAssembler::StoreRoot(Register source,
Heap::RootListIndex index,
Condition cond,
Register src1, const Operand& src2) {
Branch(2, NegateCondition(cond), src1, src2);
sw(source, MemOperand(s6, index << kPointerSizeLog2));
}
void MacroAssembler::RecordWriteHelper(Register object,
Register address,
Register scratch) {
if (emit_debug_code()) {
// Check that the object is not in new space.
Label not_in_new_space;
InNewSpace(object, scratch, ne, &not_in_new_space);
Abort("new-space object passed to RecordWriteHelper");
bind(&not_in_new_space);
}
// Calculate page address: Clear bits from 0 to kPageSizeBits.
if (mips32r2) {
Ins(object, zero_reg, 0, kPageSizeBits);
} else {
// The Ins macro is slow on r1, so use shifts instead.
srl(object, object, kPageSizeBits);
sll(object, object, kPageSizeBits);
}
// Calculate region number.
Ext(address, address, Page::kRegionSizeLog2,
kPageSizeBits - Page::kRegionSizeLog2);
// Mark region dirty.
lw(scratch, MemOperand(object, Page::kDirtyFlagOffset));
li(at, Operand(1));
sllv(at, at, address);
or_(scratch, scratch, at);
sw(scratch, MemOperand(object, Page::kDirtyFlagOffset));
}
// Push and pop all registers that can hold pointers.
void MacroAssembler::PushSafepointRegisters() {
// Safepoints expect a block of kNumSafepointRegisters values on the
// stack, so adjust the stack for unsaved registers.
const int num_unsaved = kNumSafepointRegisters - kNumSafepointSavedRegisters;
ASSERT(num_unsaved >= 0);
Subu(sp, sp, Operand(num_unsaved * kPointerSize));
MultiPush(kSafepointSavedRegisters);
}
void MacroAssembler::PopSafepointRegisters() {
const int num_unsaved = kNumSafepointRegisters - kNumSafepointSavedRegisters;
MultiPop(kSafepointSavedRegisters);
Addu(sp, sp, Operand(num_unsaved * kPointerSize));
}
void MacroAssembler::PushSafepointRegistersAndDoubles() {
PushSafepointRegisters();
Subu(sp, sp, Operand(FPURegister::kNumAllocatableRegisters * kDoubleSize));
for (int i = 0; i < FPURegister::kNumAllocatableRegisters; i+=2) {
FPURegister reg = FPURegister::FromAllocationIndex(i);
sdc1(reg, MemOperand(sp, i * kDoubleSize));
}
}
void MacroAssembler::PopSafepointRegistersAndDoubles() {
for (int i = 0; i < FPURegister::kNumAllocatableRegisters; i+=2) {
FPURegister reg = FPURegister::FromAllocationIndex(i);
ldc1(reg, MemOperand(sp, i * kDoubleSize));
}
Addu(sp, sp, Operand(FPURegister::kNumAllocatableRegisters * kDoubleSize));
PopSafepointRegisters();
}
void MacroAssembler::StoreToSafepointRegistersAndDoublesSlot(Register src,
Register dst) {
sw(src, SafepointRegistersAndDoublesSlot(dst));
}
void MacroAssembler::StoreToSafepointRegisterSlot(Register src, Register dst) {
sw(src, SafepointRegisterSlot(dst));
}
void MacroAssembler::LoadFromSafepointRegisterSlot(Register dst, Register src) {
lw(dst, SafepointRegisterSlot(src));
}
int MacroAssembler::SafepointRegisterStackIndex(int reg_code) {
// The registers are pushed starting with the highest encoding,
// which means that lowest encodings are closest to the stack pointer.
return kSafepointRegisterStackIndexMap[reg_code];
}
MemOperand MacroAssembler::SafepointRegisterSlot(Register reg) {
return MemOperand(sp, SafepointRegisterStackIndex(reg.code()) * kPointerSize);
}
MemOperand MacroAssembler::SafepointRegistersAndDoublesSlot(Register reg) {
// General purpose registers are pushed last on the stack.
int doubles_size = FPURegister::kNumAllocatableRegisters * kDoubleSize;
int register_offset = SafepointRegisterStackIndex(reg.code()) * kPointerSize;
return MemOperand(sp, doubles_size + register_offset);
}
void MacroAssembler::InNewSpace(Register object,
Register scratch,
Condition cc,
Label* branch) {
ASSERT(cc == eq || cc == ne);
And(scratch, object, Operand(ExternalReference::new_space_mask(isolate())));
Branch(branch, cc, scratch,
Operand(ExternalReference::new_space_start(isolate())));
}
// Will clobber 4 registers: object, scratch0, scratch1, at. The
// register 'object' contains a heap object pointer. The heap object
// tag is shifted away.
void MacroAssembler::RecordWrite(Register object,
Operand offset,
Register scratch0,
Register scratch1) {
// The compiled code assumes that record write doesn't change the
// context register, so we check that none of the clobbered
// registers are cp.
ASSERT(!object.is(cp) && !scratch0.is(cp) && !scratch1.is(cp));
Label done;
// First, test that the object is not in the new space. We cannot set
// region marks for new space pages.
InNewSpace(object, scratch0, eq, &done);
// Add offset into the object.
Addu(scratch0, object, offset);
// Record the actual write.
RecordWriteHelper(object, scratch0, scratch1);
bind(&done);
// Clobber all input registers when running with the debug-code flag
// turned on to provoke errors.
if (emit_debug_code()) {
li(object, Operand(BitCast<int32_t>(kZapValue)));
li(scratch0, Operand(BitCast<int32_t>(kZapValue)));
li(scratch1, Operand(BitCast<int32_t>(kZapValue)));
}
}
// Will clobber 4 registers: object, address, scratch, ip. The
// register 'object' contains a heap object pointer. The heap object
// tag is shifted away.
void MacroAssembler::RecordWrite(Register object,
Register address,
Register scratch) {
// The compiled code assumes that record write doesn't change the
// context register, so we check that none of the clobbered
// registers are cp.
ASSERT(!object.is(cp) && !address.is(cp) && !scratch.is(cp));
Label done;
// First, test that the object is not in the new space. We cannot set
// region marks for new space pages.
InNewSpace(object, scratch, eq, &done);
// Record the actual write.
RecordWriteHelper(object, address, scratch);
bind(&done);
// Clobber all input registers when running with the debug-code flag
// turned on to provoke errors.
if (emit_debug_code()) {
li(object, Operand(BitCast<int32_t>(kZapValue)));
li(address, Operand(BitCast<int32_t>(kZapValue)));
li(scratch, Operand(BitCast<int32_t>(kZapValue)));
}
}
// -----------------------------------------------------------------------------
// Allocation support.
void MacroAssembler::CheckAccessGlobalProxy(Register holder_reg,
Register scratch,
Label* miss) {
Label same_contexts;
ASSERT(!holder_reg.is(scratch));
ASSERT(!holder_reg.is(at));
ASSERT(!scratch.is(at));
// Load current lexical context from the stack frame.
lw(scratch, MemOperand(fp, StandardFrameConstants::kContextOffset));
// In debug mode, make sure the lexical context is set.
#ifdef DEBUG
Check(ne, "we should not have an empty lexical context",
scratch, Operand(zero_reg));
#endif
// Load the global context of the current context.
int offset = Context::kHeaderSize + Context::GLOBAL_INDEX * kPointerSize;
lw(scratch, FieldMemOperand(scratch, offset));
lw(scratch, FieldMemOperand(scratch, GlobalObject::kGlobalContextOffset));
// Check the context is a global context.
if (emit_debug_code()) {
// TODO(119): Avoid push(holder_reg)/pop(holder_reg).
push(holder_reg); // Temporarily save holder on the stack.
// Read the first word and compare to the global_context_map.
lw(holder_reg, FieldMemOperand(scratch, HeapObject::kMapOffset));
LoadRoot(at, Heap::kGlobalContextMapRootIndex);
Check(eq, "JSGlobalObject::global_context should be a global context.",
holder_reg, Operand(at));
pop(holder_reg); // Restore holder.
}
// Check if both contexts are the same.
lw(at, FieldMemOperand(holder_reg, JSGlobalProxy::kContextOffset));
Branch(&same_contexts, eq, scratch, Operand(at));
// Check the context is a global context.
if (emit_debug_code()) {
// TODO(119): Avoid push(holder_reg)/pop(holder_reg).
push(holder_reg); // Temporarily save holder on the stack.
mov(holder_reg, at); // Move at to its holding place.
LoadRoot(at, Heap::kNullValueRootIndex);
Check(ne, "JSGlobalProxy::context() should not be null.",
holder_reg, Operand(at));
lw(holder_reg, FieldMemOperand(holder_reg, HeapObject::kMapOffset));
LoadRoot(at, Heap::kGlobalContextMapRootIndex);
Check(eq, "JSGlobalObject::global_context should be a global context.",
holder_reg, Operand(at));
// Restore at is not needed. at is reloaded below.
pop(holder_reg); // Restore holder.
// Restore at to holder's context.
lw(at, FieldMemOperand(holder_reg, JSGlobalProxy::kContextOffset));
}
// Check that the security token in the calling global object is
// compatible with the security token in the receiving global
// object.
int token_offset = Context::kHeaderSize +
Context::SECURITY_TOKEN_INDEX * kPointerSize;
lw(scratch, FieldMemOperand(scratch, token_offset));
lw(at, FieldMemOperand(at, token_offset));
Branch(miss, ne, scratch, Operand(at));
bind(&same_contexts);
}
void MacroAssembler::LoadFromNumberDictionary(Label* miss,
Register elements,
Register key,
Register result,
Register reg0,
Register reg1,
Register reg2) {
// Register use:
//
// elements - holds the slow-case elements of the receiver on entry.
// Unchanged unless 'result' is the same register.
//
// key - holds the smi key on entry.
// Unchanged unless 'result' is the same register.
//
//
// result - holds the result on exit if the load succeeded.
// Allowed to be the same as 'key' or 'result'.
// Unchanged on bailout so 'key' or 'result' can be used
// in further computation.
//
// Scratch registers:
//
// reg0 - holds the untagged key on entry and holds the hash once computed.
//
// reg1 - Used to hold the capacity mask of the dictionary.
//
// reg2 - Used for the index into the dictionary.
// at - Temporary (avoid MacroAssembler instructions also using 'at').
Label done;
// Compute the hash code from the untagged key. This must be kept in sync
// with ComputeIntegerHash in utils.h.
//
// hash = ~hash + (hash << 15);
nor(reg1, reg0, zero_reg);
sll(at, reg0, 15);
addu(reg0, reg1, at);
// hash = hash ^ (hash >> 12);
srl(at, reg0, 12);
xor_(reg0, reg0, at);
// hash = hash + (hash << 2);
sll(at, reg0, 2);
addu(reg0, reg0, at);
// hash = hash ^ (hash >> 4);
srl(at, reg0, 4);
xor_(reg0, reg0, at);
// hash = hash * 2057;
li(reg1, Operand(2057));
mul(reg0, reg0, reg1);
// hash = hash ^ (hash >> 16);
srl(at, reg0, 16);
xor_(reg0, reg0, at);
// Compute the capacity mask.
lw(reg1, FieldMemOperand(elements, NumberDictionary::kCapacityOffset));
sra(reg1, reg1, kSmiTagSize);
Subu(reg1, reg1, Operand(1));
// Generate an unrolled loop that performs a few probes before giving up.
static const int kProbes = 4;
for (int i = 0; i < kProbes; i++) {
// Use reg2 for index calculations and keep the hash intact in reg0.
mov(reg2, reg0);
// Compute the masked index: (hash + i + i * i) & mask.
if (i > 0) {
Addu(reg2, reg2, Operand(NumberDictionary::GetProbeOffset(i)));
}
and_(reg2, reg2, reg1);
// Scale the index by multiplying by the element size.
ASSERT(NumberDictionary::kEntrySize == 3);
sll(at, reg2, 1); // 2x.
addu(reg2, reg2, at); // reg2 = reg2 * 3.
// Check if the key is identical to the name.
sll(at, reg2, kPointerSizeLog2);
addu(reg2, elements, at);
lw(at, FieldMemOperand(reg2, NumberDictionary::kElementsStartOffset));
if (i != kProbes - 1) {
Branch(&done, eq, key, Operand(at));
} else {
Branch(miss, ne, key, Operand(at));
}
}
bind(&done);
// Check that the value is a normal property.
// reg2: elements + (index * kPointerSize).
const int kDetailsOffset =
NumberDictionary::kElementsStartOffset + 2 * kPointerSize;
lw(reg1, FieldMemOperand(reg2, kDetailsOffset));
And(at, reg1, Operand(Smi::FromInt(PropertyDetails::TypeField::mask())));
Branch(miss, ne, at, Operand(zero_reg));
// Get the value at the masked, scaled index and return.
const int kValueOffset =
NumberDictionary::kElementsStartOffset + kPointerSize;
lw(result, FieldMemOperand(reg2, kValueOffset));
}
// ---------------------------------------------------------------------------
// Instruction macros.
void MacroAssembler::Addu(Register rd, Register rs, const Operand& rt) {
if (rt.is_reg()) {
addu(rd, rs, rt.rm());
} else {
if (is_int16(rt.imm32_) && !MustUseReg(rt.rmode_)) {
addiu(rd, rs, rt.imm32_);
} else {
// li handles the relocation.
ASSERT(!rs.is(at));
li(at, rt);
addu(rd, rs, at);
}
}
}
void MacroAssembler::Subu(Register rd, Register rs, const Operand& rt) {
if (rt.is_reg()) {
subu(rd, rs, rt.rm());
} else {
if (is_int16(rt.imm32_) && !MustUseReg(rt.rmode_)) {
addiu(rd, rs, -rt.imm32_); // No subiu instr, use addiu(x, y, -imm).
} else {
// li handles the relocation.
ASSERT(!rs.is(at));
li(at, rt);
subu(rd, rs, at);
}
}
}
void MacroAssembler::Mul(Register rd, Register rs, const Operand& rt) {
if (rt.is_reg()) {
mul(rd, rs, rt.rm());
} else {
// li handles the relocation.
ASSERT(!rs.is(at));
li(at, rt);
mul(rd, rs, at);
}
}
void MacroAssembler::Mult(Register rs, const Operand& rt) {
if (rt.is_reg()) {
mult(rs, rt.rm());
} else {
// li handles the relocation.
ASSERT(!rs.is(at));
li(at, rt);
mult(rs, at);
}
}
void MacroAssembler::Multu(Register rs, const Operand& rt) {
if (rt.is_reg()) {
multu(rs, rt.rm());
} else {
// li handles the relocation.
ASSERT(!rs.is(at));
li(at, rt);
multu(rs, at);
}
}
void MacroAssembler::Div(Register rs, const Operand& rt) {
if (rt.is_reg()) {
div(rs, rt.rm());
} else {
// li handles the relocation.
ASSERT(!rs.is(at));
li(at, rt);
div(rs, at);
}
}
void MacroAssembler::Divu(Register rs, const Operand& rt) {
if (rt.is_reg()) {
divu(rs, rt.rm());
} else {
// li handles the relocation.
ASSERT(!rs.is(at));
li(at, rt);
divu(rs, at);
}
}
void MacroAssembler::And(Register rd, Register rs, const Operand& rt) {
if (rt.is_reg()) {
and_(rd, rs, rt.rm());
} else {
if (is_uint16(rt.imm32_) && !MustUseReg(rt.rmode_)) {
andi(rd, rs, rt.imm32_);
} else {
// li handles the relocation.
ASSERT(!rs.is(at));
li(at, rt);
and_(rd, rs, at);
}
}
}
void MacroAssembler::Or(Register rd, Register rs, const Operand& rt) {
if (rt.is_reg()) {
or_(rd, rs, rt.rm());
} else {
if (is_uint16(rt.imm32_) && !MustUseReg(rt.rmode_)) {
ori(rd, rs, rt.imm32_);
} else {
// li handles the relocation.
ASSERT(!rs.is(at));
li(at, rt);
or_(rd, rs, at);
}
}
}
void MacroAssembler::Xor(Register rd, Register rs, const Operand& rt) {
if (rt.is_reg()) {
xor_(rd, rs, rt.rm());
} else {
if (is_uint16(rt.imm32_) && !MustUseReg(rt.rmode_)) {
xori(rd, rs, rt.imm32_);
} else {
// li handles the relocation.
ASSERT(!rs.is(at));
li(at, rt);
xor_(rd, rs, at);
}
}
}
void MacroAssembler::Nor(Register rd, Register rs, const Operand& rt) {
if (rt.is_reg()) {
nor(rd, rs, rt.rm());
} else {
// li handles the relocation.
ASSERT(!rs.is(at));
li(at, rt);
nor(rd, rs, at);
}
}
void MacroAssembler::Neg(Register rs, const Operand& rt) {
ASSERT(rt.is_reg());
ASSERT(!at.is(rs));
ASSERT(!at.is(rt.rm()));
li(at, -1);
xor_(rs, rt.rm(), at);
}
void MacroAssembler::Slt(Register rd, Register rs, const Operand& rt) {
if (rt.is_reg()) {
slt(rd, rs, rt.rm());
} else {
if (is_int16(rt.imm32_) && !MustUseReg(rt.rmode_)) {
slti(rd, rs, rt.imm32_);
} else {
// li handles the relocation.
ASSERT(!rs.is(at));
li(at, rt);
slt(rd, rs, at);
}
}
}
void MacroAssembler::Sltu(Register rd, Register rs, const Operand& rt) {
if (rt.is_reg()) {
sltu(rd, rs, rt.rm());
} else {
if (is_uint16(rt.imm32_) && !MustUseReg(rt.rmode_)) {
sltiu(rd, rs, rt.imm32_);
} else {
// li handles the relocation.
ASSERT(!rs.is(at));
li(at, rt);
sltu(rd, rs, at);
}
}
}
void MacroAssembler::Ror(Register rd, Register rs, const Operand& rt) {
if (mips32r2) {
if (rt.is_reg()) {
rotrv(rd, rs, rt.rm());
} else {
rotr(rd, rs, rt.imm32_);
}
} else {
if (rt.is_reg()) {
subu(at, zero_reg, rt.rm());
sllv(at, rs, at);
srlv(rd, rs, rt.rm());
or_(rd, rd, at);
} else {
if (rt.imm32_ == 0) {
srl(rd, rs, 0);
} else {
srl(at, rs, rt.imm32_);
sll(rd, rs, (0x20 - rt.imm32_) & 0x1f);
or_(rd, rd, at);
}
}
}
}
//------------Pseudo-instructions-------------
void MacroAssembler::li(Register rd, Operand j, bool gen2instr) {
ASSERT(!j.is_reg());
BlockTrampolinePoolScope block_trampoline_pool(this);
if (!MustUseReg(j.rmode_) && !gen2instr) {
// Normal load of an immediate value which does not need Relocation Info.
if (is_int16(j.imm32_)) {
addiu(rd, zero_reg, j.imm32_);
} else if (!(j.imm32_ & kHiMask)) {
ori(rd, zero_reg, j.imm32_);
} else if (!(j.imm32_ & kImm16Mask)) {
lui(rd, (j.imm32_ & kHiMask) >> kLuiShift);
} else {
lui(rd, (j.imm32_ & kHiMask) >> kLuiShift);
ori(rd, rd, (j.imm32_ & kImm16Mask));
}
} else if (MustUseReg(j.rmode_) || gen2instr) {
if (MustUseReg(j.rmode_)) {
RecordRelocInfo(j.rmode_, j.imm32_);
}
// We need always the same number of instructions as we may need to patch
// this code to load another value which may need 2 instructions to load.
lui(rd, (j.imm32_ & kHiMask) >> kLuiShift);
ori(rd, rd, (j.imm32_ & kImm16Mask));
}
}
void MacroAssembler::MultiPush(RegList regs) {
int16_t NumSaved = 0;
int16_t NumToPush = NumberOfBitsSet(regs);
addiu(sp, sp, -4 * NumToPush);
for (int16_t i = kNumRegisters; i > 0; i--) {
if ((regs & (1 << i)) != 0) {
sw(ToRegister(i), MemOperand(sp, 4 * (NumToPush - ++NumSaved)));
}
}
}
void MacroAssembler::MultiPushReversed(RegList regs) {
int16_t NumSaved = 0;
int16_t NumToPush = NumberOfBitsSet(regs);
addiu(sp, sp, -4 * NumToPush);
for (int16_t i = 0; i < kNumRegisters; i++) {
if ((regs & (1 << i)) != 0) {
sw(ToRegister(i), MemOperand(sp, 4 * (NumToPush - ++NumSaved)));
}
}
}
void MacroAssembler::MultiPop(RegList regs) {
int16_t NumSaved = 0;
for (int16_t i = 0; i < kNumRegisters; i++) {
if ((regs & (1 << i)) != 0) {
lw(ToRegister(i), MemOperand(sp, 4 * (NumSaved++)));
}
}
addiu(sp, sp, 4 * NumSaved);
}
void MacroAssembler::MultiPopReversed(RegList regs) {
int16_t NumSaved = 0;
for (int16_t i = kNumRegisters; i > 0; i--) {
if ((regs & (1 << i)) != 0) {
lw(ToRegister(i), MemOperand(sp, 4 * (NumSaved++)));
}
}
addiu(sp, sp, 4 * NumSaved);
}
void MacroAssembler::Ext(Register rt,
Register rs,
uint16_t pos,
uint16_t size) {
ASSERT(pos < 32);
ASSERT(pos + size < 33);
if (mips32r2) {
ext_(rt, rs, pos, size);
} else {
// Move rs to rt and shift it left then right to get the
// desired bitfield on the right side and zeroes on the left.
int shift_left = 32 - (pos + size);
sll(rt, rs, shift_left); // Acts as a move if shift_left == 0.
int shift_right = 32 - size;
if (shift_right > 0) {
srl(rt, rt, shift_right);
}
}
}
void MacroAssembler::Ins(Register rt,
Register rs,
uint16_t pos,
uint16_t size) {
ASSERT(pos < 32);
ASSERT(pos + size < 32);
if (mips32r2) {
ins_(rt, rs, pos, size);
} else {
ASSERT(!rt.is(t8) && !rs.is(t8));
srl(t8, rt, pos + size);
// The left chunk from rt that needs to
// be saved is on the right side of t8.
sll(at, t8, pos + size);
// The 'at' register now contains the left chunk on
// the left (proper position) and zeroes.
sll(t8, rt, 32 - pos);
// t8 now contains the right chunk on the left and zeroes.
srl(t8, t8, 32 - pos);
// t8 now contains the right chunk on
// the right (proper position) and zeroes.
or_(rt, at, t8);
// rt now contains the left and right chunks from the original rt
// in their proper position and zeroes in the middle.
sll(t8, rs, 32 - size);
// t8 now contains the chunk from rs on the left and zeroes.
srl(t8, t8, 32 - size - pos);
// t8 now contains the original chunk from rs in
// the middle (proper position).
or_(rt, rt, t8);
// rt now contains the result of the ins instruction in R2 mode.
}
}
void MacroAssembler::Cvt_d_uw(FPURegister fd,
FPURegister fs,
FPURegister scratch) {
// Move the data from fs to t8.
mfc1(t8, fs);
Cvt_d_uw(fd, t8, scratch);
}
void MacroAssembler::Cvt_d_uw(FPURegister fd,
Register rs,
FPURegister scratch) {
// Convert rs to a FP value in fd (and fd + 1).
// We do this by converting rs minus the MSB to avoid sign conversion,
// then adding 2^31 to the result (if needed).
ASSERT(!fd.is(scratch));
ASSERT(!rs.is(t9));
ASSERT(!rs.is(at));
// Save rs's MSB to t9.
Ext(t9, rs, 31, 1);
// Remove rs's MSB.
Ext(at, rs, 0, 31);
// Move the result to fd.
mtc1(at, fd);
// Convert fd to a real FP value.
cvt_d_w(fd, fd);
Label conversion_done;
// If rs's MSB was 0, it's done.
// Otherwise we need to add that to the FP register.
Branch(&conversion_done, eq, t9, Operand(zero_reg));
// Load 2^31 into f20 as its float representation.
li(at, 0x41E00000);
mtc1(at, FPURegister::from_code(scratch.code() + 1));
mtc1(zero_reg, scratch);
// Add it to fd.
add_d(fd, fd, scratch);
bind(&conversion_done);
}
void MacroAssembler::Trunc_uw_d(FPURegister fd,
FPURegister fs,
FPURegister scratch) {
Trunc_uw_d(fs, t8, scratch);
mtc1(t8, fd);
}
void MacroAssembler::Trunc_uw_d(FPURegister fd,
Register rs,
FPURegister scratch) {
ASSERT(!fd.is(scratch));
ASSERT(!rs.is(at));
// Load 2^31 into scratch as its float representation.
li(at, 0x41E00000);
mtc1(at, FPURegister::from_code(scratch.code() + 1));
mtc1(zero_reg, scratch);
// Test if scratch > fd.
c(OLT, D, fd, scratch);
Label simple_convert;
// If fd < 2^31 we can convert it normally.
bc1t(&simple_convert);
// First we subtract 2^31 from fd, then trunc it to rs
// and add 2^31 to rs.
sub_d(scratch, fd, scratch);
trunc_w_d(scratch, scratch);
mfc1(rs, scratch);
Or(rs, rs, 1 << 31);
Label done;
Branch(&done);
// Simple conversion.
bind(&simple_convert);
trunc_w_d(scratch, fd);
mfc1(rs, scratch);
bind(&done);
}
// Tries to get a signed int32 out of a double precision floating point heap
// number. Rounds towards 0. Branch to 'not_int32' if the double is out of the
// 32bits signed integer range.
// This method implementation differs from the ARM version for performance
// reasons.
void MacroAssembler::ConvertToInt32(Register source,
Register dest,
Register scratch,
Register scratch2,
FPURegister double_scratch,
Label *not_int32) {
Label right_exponent, done;
// Get exponent word (ENDIAN issues).
lw(scratch, FieldMemOperand(source, HeapNumber::kExponentOffset));
// Get exponent alone in scratch2.
And(scratch2, scratch, Operand(HeapNumber::kExponentMask));
// Load dest with zero. We use this either for the final shift or
// for the answer.
mov(dest, zero_reg);
// Check whether the exponent matches a 32 bit signed int that is not a Smi.
// A non-Smi integer is 1.xxx * 2^30 so the exponent is 30 (biased). This is
// the exponent that we are fastest at and also the highest exponent we can
// handle here.
const uint32_t non_smi_exponent =
(HeapNumber::kExponentBias + 30) << HeapNumber::kExponentShift;
// If we have a match of the int32-but-not-Smi exponent then skip some logic.
Branch(&right_exponent, eq, scratch2, Operand(non_smi_exponent));
// If the exponent is higher than that then go to not_int32 case. This
// catches numbers that don't fit in a signed int32, infinities and NaNs.
Branch(not_int32, gt, scratch2, Operand(non_smi_exponent));
// We know the exponent is smaller than 30 (biased). If it is less than
// 0 (biased) then the number is smaller in magnitude than 1.0 * 2^0, ie
// it rounds to zero.
const uint32_t zero_exponent =
(HeapNumber::kExponentBias + 0) << HeapNumber::kExponentShift;
Subu(scratch2, scratch2, Operand(zero_exponent));
// Dest already has a Smi zero.
Branch(&done, lt, scratch2, Operand(zero_reg));
if (!CpuFeatures::IsSupported(FPU)) {
// We have a shifted exponent between 0 and 30 in scratch2.
srl(dest, scratch2, HeapNumber::kExponentShift);
// We now have the exponent in dest. Subtract from 30 to get
// how much to shift down.
li(at, Operand(30));
subu(dest, at, dest);
}
bind(&right_exponent);
if (CpuFeatures::IsSupported(FPU)) {
CpuFeatures::Scope scope(FPU);
// MIPS FPU instructions implementing double precision to integer
// conversion using round to zero. Since the FP value was qualified
// above, the resulting integer should be a legal int32.
// The original 'Exponent' word is still in scratch.
lwc1(double_scratch, FieldMemOperand(source, HeapNumber::kMantissaOffset));
mtc1(scratch, FPURegister::from_code(double_scratch.code() + 1));
trunc_w_d(double_scratch, double_scratch);
mfc1(dest, double_scratch);
} else {
// On entry, dest has final downshift, scratch has original sign/exp/mant.
// Save sign bit in top bit of dest.
And(scratch2, scratch, Operand(0x80000000));
Or(dest, dest, Operand(scratch2));
// Put back the implicit 1, just above mantissa field.
Or(scratch, scratch, Operand(1 << HeapNumber::kExponentShift));
// Shift up the mantissa bits to take up the space the exponent used to
// take. We just orred in the implicit bit so that took care of one and
// we want to leave the sign bit 0 so we subtract 2 bits from the shift
// distance. But we want to clear the sign-bit so shift one more bit
// left, then shift right one bit.
const int shift_distance = HeapNumber::kNonMantissaBitsInTopWord - 2;
sll(scratch, scratch, shift_distance + 1);
srl(scratch, scratch, 1);
// Get the second half of the double. For some exponents we don't
// actually need this because the bits get shifted out again, but
// it's probably slower to test than just to do it.
lw(scratch2, FieldMemOperand(source, HeapNumber::kMantissaOffset));
// Extract the top 10 bits, and insert those bottom 10 bits of scratch.
// The width of the field here is the same as the shift amount above.
const int field_width = shift_distance;
Ext(scratch2, scratch2, 32-shift_distance, field_width);
Ins(scratch, scratch2, 0, field_width);
// Move down according to the exponent.
srlv(scratch, scratch, dest);
// Prepare the negative version of our integer.
subu(scratch2, zero_reg, scratch);
// Trick to check sign bit (msb) held in dest, count leading zero.
// 0 indicates negative, save negative version with conditional move.
clz(dest, dest);
movz(scratch, scratch2, dest);
mov(dest, scratch);
}
bind(&done);
}
void MacroAssembler::EmitOutOfInt32RangeTruncate(Register result,
Register input_high,
Register input_low,
Register scratch) {
Label done, normal_exponent, restore_sign;
// Extract the biased exponent in result.
Ext(result,
input_high,
HeapNumber::kExponentShift,
HeapNumber::kExponentBits);
// Check for Infinity and NaNs, which should return 0.
Subu(scratch, result, HeapNumber::kExponentMask);
movz(result, zero_reg, scratch);
Branch(&done, eq, scratch, Operand(zero_reg));
// Express exponent as delta to (number of mantissa bits + 31).
Subu(result,
result,
Operand(HeapNumber::kExponentBias + HeapNumber::kMantissaBits + 31));
// If the delta is strictly positive, all bits would be shifted away,
// which means that we can return 0.
Branch(&normal_exponent, le, result, Operand(zero_reg));
mov(result, zero_reg);
Branch(&done);
bind(&normal_exponent);
const int kShiftBase = HeapNumber::kNonMantissaBitsInTopWord - 1;
// Calculate shift.
Addu(scratch, result, Operand(kShiftBase + HeapNumber::kMantissaBits));
// Save the sign.
Register sign = result;
result = no_reg;
And(sign, input_high, Operand(HeapNumber::kSignMask));
// On ARM shifts > 31 bits are valid and will result in zero. On MIPS we need
// to check for this specific case.
Label high_shift_needed, high_shift_done;
Branch(&high_shift_needed, lt, scratch, Operand(32));
mov(input_high, zero_reg);
Branch(&high_shift_done);
bind(&high_shift_needed);
// Set the implicit 1 before the mantissa part in input_high.
Or(input_high,
input_high,
Operand(1 << HeapNumber::kMantissaBitsInTopWord));
// Shift the mantissa bits to the correct position.
// We don't need to clear non-mantissa bits as they will be shifted away.
// If they weren't, it would mean that the answer is in the 32bit range.
sllv(input_high, input_high, scratch);
bind(&high_shift_done);
// Replace the shifted bits with bits from the lower mantissa word.
Label pos_shift, shift_done;
li(at, 32);
subu(scratch, at, scratch);
Branch(&pos_shift, ge, scratch, Operand(zero_reg));
// Negate scratch.
Subu(scratch, zero_reg, scratch);
sllv(input_low, input_low, scratch);
Branch(&shift_done);
bind(&pos_shift);
srlv(input_low, input_low, scratch);
bind(&shift_done);
Or(input_high, input_high, Operand(input_low));
// Restore sign if necessary.
mov(scratch, sign);
result = sign;
sign = no_reg;
Subu(result, zero_reg, input_high);
movz(result, input_high, scratch);
bind(&done);
}
void MacroAssembler::EmitECMATruncate(Register result,
FPURegister double_input,
FPURegister single_scratch,
Register scratch,
Register input_high,
Register input_low) {
CpuFeatures::Scope scope(FPU);
ASSERT(!input_high.is(result));
ASSERT(!input_low.is(result));
ASSERT(!input_low.is(input_high));
ASSERT(!scratch.is(result) &&
!scratch.is(input_high) &&
!scratch.is(input_low));
ASSERT(!single_scratch.is(double_input));
Label done;
Label manual;
// Clear cumulative exception flags and save the FCSR.
Register scratch2 = input_high;
cfc1(scratch2, FCSR);
ctc1(zero_reg, FCSR);
// Try a conversion to a signed integer.
trunc_w_d(single_scratch, double_input);
mfc1(result, single_scratch);
// Retrieve and restore the FCSR.
cfc1(scratch, FCSR);
ctc1(scratch2, FCSR);
// Check for overflow and NaNs.
And(scratch,
scratch,
kFCSROverflowFlagMask | kFCSRUnderflowFlagMask | kFCSRInvalidOpFlagMask);
// If we had no exceptions we are done.
Branch(&done, eq, scratch, Operand(zero_reg));
// Load the double value and perform a manual truncation.
Move(input_low, input_high, double_input);
EmitOutOfInt32RangeTruncate(result,
input_high,
input_low,
scratch);
bind(&done);
}
void MacroAssembler::GetLeastBitsFromSmi(Register dst,
Register src,
int num_least_bits) {
Ext(dst, src, kSmiTagSize, num_least_bits);
}
void MacroAssembler::GetLeastBitsFromInt32(Register dst,
Register src,
int num_least_bits) {
And(dst, src, Operand((1 << num_least_bits) - 1));
}
// Emulated condtional branches do not emit a nop in the branch delay slot.
//
// BRANCH_ARGS_CHECK checks that conditional jump arguments are correct.
#define BRANCH_ARGS_CHECK(cond, rs, rt) ASSERT( \
(cond == cc_always && rs.is(zero_reg) && rt.rm().is(zero_reg)) || \
(cond != cc_always && (!rs.is(zero_reg) || !rt.rm().is(zero_reg))))
bool MacroAssembler::UseAbsoluteCodePointers() {
if (is_trampoline_emitted()) {
return true;
} else {
return false;
}
}
void MacroAssembler::Branch(int16_t offset, BranchDelaySlot bdslot) {
BranchShort(offset, bdslot);
}
void MacroAssembler::Branch(int16_t offset, Condition cond, Register rs,
const Operand& rt,
BranchDelaySlot bdslot) {
BranchShort(offset, cond, rs, rt, bdslot);
}
void MacroAssembler::Branch(Label* L, BranchDelaySlot bdslot) {
bool is_label_near = is_near(L);
if (UseAbsoluteCodePointers() && !is_label_near) {
Jr(L, bdslot);
} else {
BranchShort(L, bdslot);
}
}
void MacroAssembler::Branch(Label* L, Condition cond, Register rs,
const Operand& rt,
BranchDelaySlot bdslot) {
bool is_label_near = is_near(L);
if (UseAbsoluteCodePointers() && !is_label_near) {
Label skip;
Condition neg_cond = NegateCondition(cond);
BranchShort(&skip, neg_cond, rs, rt);
Jr(L, bdslot);
bind(&skip);
} else {
BranchShort(L, cond, rs, rt, bdslot);
}
}
void MacroAssembler::BranchShort(int16_t offset, BranchDelaySlot bdslot) {
b(offset);
// Emit a nop in the branch delay slot if required.
if (bdslot == PROTECT)
nop();
}
void MacroAssembler::BranchShort(int16_t offset, Condition cond, Register rs,
const Operand& rt,
BranchDelaySlot bdslot) {
BRANCH_ARGS_CHECK(cond, rs, rt);
ASSERT(!rs.is(zero_reg));
Register r2 = no_reg;
Register scratch = at;
if (rt.is_reg()) {
// We don't want any other register but scratch clobbered.
ASSERT(!scratch.is(rs) && !scratch.is(rt.rm_));
r2 = rt.rm_;
switch (cond) {
case cc_always:
b(offset);
break;
case eq:
beq(rs, r2, offset);
break;
case ne:
bne(rs, r2, offset);
break;
// Signed comparison.
case greater:
if (r2.is(zero_reg)) {
bgtz(rs, offset);
} else {
slt(scratch, r2, rs);
bne(scratch, zero_reg, offset);
}
break;
case greater_equal:
if (r2.is(zero_reg)) {
bgez(rs, offset);
} else {
slt(scratch, rs, r2);
beq(scratch, zero_reg, offset);
}
break;
case less:
if (r2.is(zero_reg)) {
bltz(rs, offset);
} else {
slt(scratch, rs, r2);
bne(scratch, zero_reg, offset);
}
break;
case less_equal:
if (r2.is(zero_reg)) {
blez(rs, offset);
} else {
slt(scratch, r2, rs);
beq(scratch, zero_reg, offset);
}
break;
// Unsigned comparison.
case Ugreater:
if (r2.is(zero_reg)) {
bgtz(rs, offset);
} else {
sltu(scratch, r2, rs);
bne(scratch, zero_reg, offset);
}
break;
case Ugreater_equal:
if (r2.is(zero_reg)) {
bgez(rs, offset);
} else {
sltu(scratch, rs, r2);
beq(scratch, zero_reg, offset);
}
break;
case Uless:
if (r2.is(zero_reg)) {
// No code needs to be emitted.
return;
} else {
sltu(scratch, rs, r2);
bne(scratch, zero_reg, offset);
}
break;
case Uless_equal:
if (r2.is(zero_reg)) {
b(offset);
} else {
sltu(scratch, r2, rs);
beq(scratch, zero_reg, offset);
}
break;
default:
UNREACHABLE();
}
} else {
// Be careful to always use shifted_branch_offset only just before the
// branch instruction, as the location will be remember for patching the
// target.
switch (cond) {
case cc_always:
b(offset);
break;
case eq:
// We don't want any other register but scratch clobbered.
ASSERT(!scratch.is(rs));
r2 = scratch;
li(r2, rt);
beq(rs, r2, offset);
break;
case ne:
// We don't want any other register but scratch clobbered.
ASSERT(!scratch.is(rs));
r2 = scratch;
li(r2, rt);
bne(rs, r2, offset);
break;
// Signed comparison.
case greater:
if (rt.imm32_ == 0) {
bgtz(rs, offset);
} else {
r2 = scratch;
li(r2, rt);
slt(scratch, r2, rs);
bne(scratch, zero_reg, offset);
}
break;
case greater_equal:
if (rt.imm32_ == 0) {
bgez(rs, offset);
} else if (is_int16(rt.imm32_)) {
slti(scratch, rs, rt.imm32_);
beq(scratch, zero_reg, offset);
} else {
r2 = scratch;
li(r2, rt);
slt(scratch, rs, r2);
beq(scratch, zero_reg, offset);
}
break;
case less:
if (rt.imm32_ == 0) {
bltz(rs, offset);
} else if (is_int16(rt.imm32_)) {
slti(scratch, rs, rt.imm32_);
bne(scratch, zero_reg, offset);
} else {
r2 = scratch;
li(r2, rt);
slt(scratch, rs, r2);
bne(scratch, zero_reg, offset);
}
break;
case less_equal:
if (rt.imm32_ == 0) {
blez(rs, offset);
} else {
r2 = scratch;
li(r2, rt);
slt(scratch, r2, rs);
beq(scratch, zero_reg, offset);
}
break;
// Unsigned comparison.
case Ugreater:
if (rt.imm32_ == 0) {
bgtz(rs, offset);
} else {
r2 = scratch;
li(r2, rt);
sltu(scratch, r2, rs);
bne(scratch, zero_reg, offset);
}
break;
case Ugreater_equal:
if (rt.imm32_ == 0) {
bgez(rs, offset);
} else if (is_int16(rt.imm32_)) {
sltiu(scratch, rs, rt.imm32_);
beq(scratch, zero_reg, offset);
} else {
r2 = scratch;
li(r2, rt);
sltu(scratch, rs, r2);
beq(scratch, zero_reg, offset);
}
break;
case Uless:
if (rt.imm32_ == 0) {
// No code needs to be emitted.
return;
} else if (is_int16(rt.imm32_)) {
sltiu(scratch, rs, rt.imm32_);
bne(scratch, zero_reg, offset);
} else {
r2 = scratch;
li(r2, rt);
sltu(scratch, rs, r2);
bne(scratch, zero_reg, offset);
}
break;
case Uless_equal:
if (rt.imm32_ == 0) {
b(offset);
} else {
r2 = scratch;
li(r2, rt);
sltu(scratch, r2, rs);
beq(scratch, zero_reg, offset);
}
break;
default:
UNREACHABLE();
}
}
// Emit a nop in the branch delay slot if required.
if (bdslot == PROTECT)
nop();
}
void MacroAssembler::BranchShort(Label* L, BranchDelaySlot bdslot) {
// We use branch_offset as an argument for the branch instructions to be sure
// it is called just before generating the branch instruction, as needed.
b(shifted_branch_offset(L, false));
// Emit a nop in the branch delay slot if required.
if (bdslot == PROTECT)
nop();
}
void MacroAssembler::BranchShort(Label* L, Condition cond, Register rs,
const Operand& rt,
BranchDelaySlot bdslot) {
BRANCH_ARGS_CHECK(cond, rs, rt);
int32_t offset;
Register r2 = no_reg;
Register scratch = at;
if (rt.is_reg()) {
r2 = rt.rm_;
// Be careful to always use shifted_branch_offset only just before the
// branch instruction, as the location will be remember for patching the
// target.
switch (cond) {
case cc_always:
offset = shifted_branch_offset(L, false);
b(offset);
break;
case eq:
offset = shifted_branch_offset(L, false);
beq(rs, r2, offset);
break;
case ne:
offset = shifted_branch_offset(L, false);
bne(rs, r2, offset);
break;
// Signed comparison.
case greater:
if (r2.is(zero_reg)) {
offset = shifted_branch_offset(L, false);
bgtz(rs, offset);
} else {
slt(scratch, r2, rs);
offset = shifted_branch_offset(L, false);
bne(scratch, zero_reg, offset);
}
break;
case greater_equal:
if (r2.is(zero_reg)) {
offset = shifted_branch_offset(L, false);
bgez(rs, offset);
} else {
slt(scratch, rs, r2);
offset = shifted_branch_offset(L, false);
beq(scratch, zero_reg, offset);
}
break;
case less:
if (r2.is(zero_reg)) {
offset = shifted_branch_offset(L, false);
bltz(rs, offset);
} else {
slt(scratch, rs, r2);
offset = shifted_branch_offset(L, false);
bne(scratch, zero_reg, offset);
}
break;
case less_equal:
if (r2.is(zero_reg)) {
offset = shifted_branch_offset(L, false);
blez(rs, offset);
} else {
slt(scratch, r2, rs);
offset = shifted_branch_offset(L, false);
beq(scratch, zero_reg, offset);
}
break;
// Unsigned comparison.
case Ugreater:
if (r2.is(zero_reg)) {
offset = shifted_branch_offset(L, false);
bgtz(rs, offset);
} else {
sltu(scratch, r2, rs);
offset = shifted_branch_offset(L, false);
bne(scratch, zero_reg, offset);
}
break;
case Ugreater_equal:
if (r2.is(zero_reg)) {
offset = shifted_branch_offset(L, false);
bgez(rs, offset);
} else {
sltu(scratch, rs, r2);
offset = shifted_branch_offset(L, false);
beq(scratch, zero_reg, offset);
}
break;
case Uless:
if (r2.is(zero_reg)) {
// No code needs to be emitted.
return;
} else {
sltu(scratch, rs, r2);
offset = shifted_branch_offset(L, false);
bne(scratch, zero_reg, offset);
}
break;
case Uless_equal:
if (r2.is(zero_reg)) {
offset = shifted_branch_offset(L, false);
b(offset);
} else {
sltu(scratch, r2, rs);
offset = shifted_branch_offset(L, false);
beq(scratch, zero_reg, offset);
}
break;
default:
UNREACHABLE();
}
} else {
// Be careful to always use shifted_branch_offset only just before the
// branch instruction, as the location will be remember for patching the
// target.
switch (cond) {
case cc_always:
offset = shifted_branch_offset(L, false);
b(offset);
break;
case eq:
ASSERT(!scratch.is(rs));
r2 = scratch;
li(r2, rt);
offset = shifted_branch_offset(L, false);
beq(rs, r2, offset);
break;
case ne:
ASSERT(!scratch.is(rs));
r2 = scratch;
li(r2, rt);
offset = shifted_branch_offset(L, false);
bne(rs, r2, offset);
break;
// Signed comparison.
case greater:
if (rt.imm32_ == 0) {
offset = shifted_branch_offset(L, false);
bgtz(rs, offset);
} else {
ASSERT(!scratch.is(rs));
r2 = scratch;
li(r2, rt);
slt(scratch, r2, rs);
offset = shifted_branch_offset(L, false);
bne(scratch, zero_reg, offset);
}
break;
case greater_equal:
if (rt.imm32_ == 0) {
offset = shifted_branch_offset(L, false);
bgez(rs, offset);
} else if (is_int16(rt.imm32_)) {
slti(scratch, rs, rt.imm32_);
offset = shifted_branch_offset(L, false);
beq(scratch, zero_reg, offset);
} else {
ASSERT(!scratch.is(rs));
r2 = scratch;
li(r2, rt);
slt(scratch, rs, r2);
offset = shifted_branch_offset(L, false);
beq(scratch, zero_reg, offset);
}
break;
case less:
if (rt.imm32_ == 0) {
offset = shifted_branch_offset(L, false);
bltz(rs, offset);
} else if (is_int16(rt.imm32_)) {
slti(scratch, rs, rt.imm32_);
offset = shifted_branch_offset(L, false);
bne(scratch, zero_reg, offset);
} else {
ASSERT(!scratch.is(rs));
r2 = scratch;
li(r2, rt);
slt(scratch, rs, r2);
offset = shifted_branch_offset(L, false);
bne(scratch, zero_reg, offset);
}
break;
case less_equal:
if (rt.imm32_ == 0) {
offset = shifted_branch_offset(L, false);
blez(rs, offset);
} else {
ASSERT(!scratch.is(rs));
r2 = scratch;
li(r2, rt);
slt(scratch, r2, rs);
offset = shifted_branch_offset(L, false);
beq(scratch, zero_reg, offset);
}
break;
// Unsigned comparison.
case Ugreater:
if (rt.imm32_ == 0) {
offset = shifted_branch_offset(L, false);
bgtz(rs, offset);
} else {
ASSERT(!scratch.is(rs));
r2 = scratch;
li(r2, rt);
sltu(scratch, r2, rs);
offset = shifted_branch_offset(L, false);
bne(scratch, zero_reg, offset);
}
break;
case Ugreater_equal:
if (rt.imm32_ == 0) {
offset = shifted_branch_offset(L, false);
bgez(rs, offset);
} else if (is_int16(rt.imm32_)) {
sltiu(scratch, rs, rt.imm32_);
offset = shifted_branch_offset(L, false);
beq(scratch, zero_reg, offset);
} else {
ASSERT(!scratch.is(rs));
r2 = scratch;
li(r2, rt);
sltu(scratch, rs, r2);
offset = shifted_branch_offset(L, false);
beq(scratch, zero_reg, offset);
}
break;
case Uless:
if (rt.imm32_ == 0) {
// No code needs to be emitted.
return;
} else if (is_int16(rt.imm32_)) {
sltiu(scratch, rs, rt.imm32_);
offset = shifted_branch_offset(L, false);
bne(scratch, zero_reg, offset);
} else {
ASSERT(!scratch.is(rs));
r2 = scratch;
li(r2, rt);
sltu(scratch, rs, r2);
offset = shifted_branch_offset(L, false);
bne(scratch, zero_reg, offset);
}
break;
case Uless_equal:
if (rt.imm32_ == 0) {
offset = shifted_branch_offset(L, false);
b(offset);
} else {
ASSERT(!scratch.is(rs));
r2 = scratch;
li(r2, rt);
sltu(scratch, r2, rs);
offset = shifted_branch_offset(L, false);
beq(scratch, zero_reg, offset);
}
break;
default:
UNREACHABLE();
}
}
// Check that offset could actually hold on an int16_t.
ASSERT(is_int16(offset));
// Emit a nop in the branch delay slot if required.
if (bdslot == PROTECT)
nop();
}
void MacroAssembler::BranchAndLink(int16_t offset, BranchDelaySlot bdslot) {
BranchAndLinkShort(offset, bdslot);
}
void MacroAssembler::BranchAndLink(int16_t offset, Condition cond, Register rs,
const Operand& rt,
BranchDelaySlot bdslot) {
BranchAndLinkShort(offset, cond, rs, rt, bdslot);
}
void MacroAssembler::BranchAndLink(Label* L, BranchDelaySlot bdslot) {
bool is_label_near = is_near(L);
if (UseAbsoluteCodePointers() && !is_label_near) {
Jalr(L, bdslot);
} else {
BranchAndLinkShort(L, bdslot);
}
}
void MacroAssembler::BranchAndLink(Label* L, Condition cond, Register rs,
const Operand& rt,
BranchDelaySlot bdslot) {
bool is_label_near = is_near(L);
if (UseAbsoluteCodePointers() && !is_label_near) {
Label skip;
Condition neg_cond = NegateCondition(cond);
BranchShort(&skip, neg_cond, rs, rt);
Jalr(L, bdslot);
bind(&skip);
} else {
BranchAndLinkShort(L, cond, rs, rt, bdslot);
}
}
// We need to use a bgezal or bltzal, but they can't be used directly with the
// slt instructions. We could use sub or add instead but we would miss overflow
// cases, so we keep slt and add an intermediate third instruction.
void MacroAssembler::BranchAndLinkShort(int16_t offset,
BranchDelaySlot bdslot) {
bal(offset);
// Emit a nop in the branch delay slot if required.
if (bdslot == PROTECT)
nop();
}
void MacroAssembler::BranchAndLinkShort(int16_t offset, Condition cond,
Register rs, const Operand& rt,
BranchDelaySlot bdslot) {
BRANCH_ARGS_CHECK(cond, rs, rt);
Register r2 = no_reg;
Register scratch = at;
if (rt.is_reg()) {
r2 = rt.rm_;
} else if (cond != cc_always) {
r2 = scratch;
li(r2, rt);
}
switch (cond) {
case cc_always:
bal(offset);
break;
case eq:
bne(rs, r2, 2);
nop();
bal(offset);
break;
case ne:
beq(rs, r2, 2);
nop();
bal(offset);
break;
// Signed comparison.
case greater:
slt(scratch, r2, rs);
addiu(scratch, scratch, -1);
bgezal(scratch, offset);
break;
case greater_equal:
slt(scratch, rs, r2);
addiu(scratch, scratch, -1);
bltzal(scratch, offset);
break;
case less:
slt(scratch, rs, r2);
addiu(scratch, scratch, -1);
bgezal(scratch, offset);
break;
case less_equal:
slt(scratch, r2, rs);
addiu(scratch, scratch, -1);
bltzal(scratch, offset);
break;
// Unsigned comparison.
case Ugreater:
sltu(scratch, r2, rs);
addiu(scratch, scratch, -1);
bgezal(scratch, offset);
break;
case Ugreater_equal:
sltu(scratch, rs, r2);
addiu(scratch, scratch, -1);
bltzal(scratch, offset);
break;
case Uless:
sltu(scratch, rs, r2);
addiu(scratch, scratch, -1);
bgezal(scratch, offset);
break;
case Uless_equal:
sltu(scratch, r2, rs);
addiu(scratch, scratch, -1);
bltzal(scratch, offset);
break;
default:
UNREACHABLE();
}
// Emit a nop in the branch delay slot if required.
if (bdslot == PROTECT)
nop();
}
void MacroAssembler::BranchAndLinkShort(Label* L, BranchDelaySlot bdslot) {
bal(shifted_branch_offset(L, false));
// Emit a nop in the branch delay slot if required.
if (bdslot == PROTECT)
nop();
}
void MacroAssembler::BranchAndLinkShort(Label* L, Condition cond, Register rs,
const Operand& rt,
BranchDelaySlot bdslot) {
BRANCH_ARGS_CHECK(cond, rs, rt);
int32_t offset;
Register r2 = no_reg;
Register scratch = at;
if (rt.is_reg()) {
r2 = rt.rm_;
} else if (cond != cc_always) {
r2 = scratch;
li(r2, rt);
}
switch (cond) {
case cc_always:
offset = shifted_branch_offset(L, false);
bal(offset);
break;
case eq:
bne(rs, r2, 2);
nop();
offset = shifted_branch_offset(L, false);
bal(offset);
break;
case ne:
beq(rs, r2, 2);
nop();
offset = shifted_branch_offset(L, false);
bal(offset);
break;
// Signed comparison.
case greater:
slt(scratch, r2, rs);
addiu(scratch, scratch, -1);
offset = shifted_branch_offset(L, false);
bgezal(scratch, offset);
break;
case greater_equal:
slt(scratch, rs, r2);
addiu(scratch, scratch, -1);
offset = shifted_branch_offset(L, false);
bltzal(scratch, offset);
break;
case less:
slt(scratch, rs, r2);
addiu(scratch, scratch, -1);
offset = shifted_branch_offset(L, false);
bgezal(scratch, offset);
break;
case less_equal:
slt(scratch, r2, rs);
addiu(scratch, scratch, -1);
offset = shifted_branch_offset(L, false);
bltzal(scratch, offset);
break;
// Unsigned comparison.
case Ugreater:
sltu(scratch, r2, rs);
addiu(scratch, scratch, -1);
offset = shifted_branch_offset(L, false);
bgezal(scratch, offset);
break;
case Ugreater_equal:
sltu(scratch, rs, r2);
addiu(scratch, scratch, -1);
offset = shifted_branch_offset(L, false);
bltzal(scratch, offset);
break;
case Uless:
sltu(scratch, rs, r2);
addiu(scratch, scratch, -1);
offset = shifted_branch_offset(L, false);
bgezal(scratch, offset);
break;
case Uless_equal:
sltu(scratch, r2, rs);
addiu(scratch, scratch, -1);
offset = shifted_branch_offset(L, false);
bltzal(scratch, offset);
break;
default:
UNREACHABLE();
}
// Check that offset could actually hold on an int16_t.
ASSERT(is_int16(offset));
// Emit a nop in the branch delay slot if required.
if (bdslot == PROTECT)
nop();
}
void MacroAssembler::Jump(Register target,
Condition cond,
Register rs,
const Operand& rt,
BranchDelaySlot bd) {
BlockTrampolinePoolScope block_trampoline_pool(this);
if (cond == cc_always) {
jr(target);
} else {
BRANCH_ARGS_CHECK(cond, rs, rt);
Branch(2, NegateCondition(cond), rs, rt);
jr(target);
}
// Emit a nop in the branch delay slot if required.
if (bd == PROTECT)
nop();
}
void MacroAssembler::Jump(intptr_t target,
RelocInfo::Mode rmode,
Condition cond,
Register rs,
const Operand& rt,
BranchDelaySlot bd) {
li(t9, Operand(target, rmode));
Jump(t9, cond, rs, rt, bd);
}
void MacroAssembler::Jump(Address target,
RelocInfo::Mode rmode,
Condition cond,
Register rs,
const Operand& rt,
BranchDelaySlot bd) {
ASSERT(!RelocInfo::IsCodeTarget(rmode));
Jump(reinterpret_cast<intptr_t>(target), rmode, cond, rs, rt, bd);
}
void MacroAssembler::Jump(Handle<Code> code,
RelocInfo::Mode rmode,
Condition cond,
Register rs,
const Operand& rt,
BranchDelaySlot bd) {
ASSERT(RelocInfo::IsCodeTarget(rmode));
Jump(reinterpret_cast<intptr_t>(code.location()), rmode, cond, rs, rt, bd);
}
int MacroAssembler::CallSize(Register target,
Condition cond,
Register rs,
const Operand& rt,
BranchDelaySlot bd) {
int size = 0;
if (cond == cc_always) {
size += 1;
} else {
size += 3;
}
if (bd == PROTECT)
size += 1;
return size * kInstrSize;
}
// Note: To call gcc-compiled C code on mips, you must call thru t9.
void MacroAssembler::Call(Register target,
Condition cond,
Register rs,
const Operand& rt,
BranchDelaySlot bd) {
BlockTrampolinePoolScope block_trampoline_pool(this);
Label start;
bind(&start);
if (cond == cc_always) {
jalr(target);
} else {
BRANCH_ARGS_CHECK(cond, rs, rt);
Branch(2, NegateCondition(cond), rs, rt);
jalr(target);
}
// Emit a nop in the branch delay slot if required.
if (bd == PROTECT)
nop();
ASSERT_EQ(CallSize(target, cond, rs, rt, bd),
SizeOfCodeGeneratedSince(&start));
}
int MacroAssembler::CallSize(Address target,
RelocInfo::Mode rmode,
Condition cond,
Register rs,
const Operand& rt,
BranchDelaySlot bd) {
int size = CallSize(t9, cond, rs, rt, bd);
return size + 2 * kInstrSize;
}
void MacroAssembler::Call(Address target,
RelocInfo::Mode rmode,
Condition cond,
Register rs,
const Operand& rt,
BranchDelaySlot bd) {
BlockTrampolinePoolScope block_trampoline_pool(this);
Label start;
bind(&start);
int32_t target_int = reinterpret_cast<int32_t>(target);
// Must record previous source positions before the
// li() generates a new code target.
positions_recorder()->WriteRecordedPositions();
li(t9, Operand(target_int, rmode), true);
Call(t9, cond, rs, rt, bd);
ASSERT_EQ(CallSize(target, rmode, cond, rs, rt, bd),
SizeOfCodeGeneratedSince(&start));
}
int MacroAssembler::CallSize(Handle<Code> code,
RelocInfo::Mode rmode,
unsigned ast_id,
Condition cond,
Register rs,
const Operand& rt,
BranchDelaySlot bd) {
return CallSize(reinterpret_cast<Address>(code.location()),
rmode, cond, rs, rt, bd);
}
void MacroAssembler::Call(Handle<Code> code,
RelocInfo::Mode rmode,
unsigned ast_id,
Condition cond,
Register rs,
const Operand& rt,
BranchDelaySlot bd) {
BlockTrampolinePoolScope block_trampoline_pool(this);
Label start;
bind(&start);
ASSERT(RelocInfo::IsCodeTarget(rmode));
if (rmode == RelocInfo::CODE_TARGET && ast_id != kNoASTId) {
SetRecordedAstId(ast_id);
rmode = RelocInfo::CODE_TARGET_WITH_ID;
}
Call(reinterpret_cast<Address>(code.location()), rmode, cond, rs, rt, bd);
ASSERT_EQ(CallSize(code, rmode, ast_id, cond, rs, rt),
SizeOfCodeGeneratedSince(&start));
}
void MacroAssembler::Ret(Condition cond,
Register rs,
const Operand& rt,
BranchDelaySlot bd) {
Jump(ra, cond, rs, rt, bd);
}
void MacroAssembler::J(Label* L, BranchDelaySlot bdslot) {
BlockTrampolinePoolScope block_trampoline_pool(this);
uint32_t imm28;
imm28 = jump_address(L);
imm28 &= kImm28Mask;
{ BlockGrowBufferScope block_buf_growth(this);
// Buffer growth (and relocation) must be blocked for internal references
// until associated instructions are emitted and available to be patched.
RecordRelocInfo(RelocInfo::INTERNAL_REFERENCE);
j(imm28);
}
// Emit a nop in the branch delay slot if required.
if (bdslot == PROTECT)
nop();
}
void MacroAssembler::Jr(Label* L, BranchDelaySlot bdslot) {
BlockTrampolinePoolScope block_trampoline_pool(this);
uint32_t imm32;
imm32 = jump_address(L);
{ BlockGrowBufferScope block_buf_growth(this);
// Buffer growth (and relocation) must be blocked for internal references
// until associated instructions are emitted and available to be patched.
RecordRelocInfo(RelocInfo::INTERNAL_REFERENCE);
lui(at, (imm32 & kHiMask) >> kLuiShift);
ori(at, at, (imm32 & kImm16Mask));
}
jr(at);
// Emit a nop in the branch delay slot if required.
if (bdslot == PROTECT)
nop();
}
void MacroAssembler::Jalr(Label* L, BranchDelaySlot bdslot) {
BlockTrampolinePoolScope block_trampoline_pool(this);
uint32_t imm32;
imm32 = jump_address(L);
{ BlockGrowBufferScope block_buf_growth(this);
// Buffer growth (and relocation) must be blocked for internal references
// until associated instructions are emitted and available to be patched.
RecordRelocInfo(RelocInfo::INTERNAL_REFERENCE);
lui(at, (imm32 & kHiMask) >> kLuiShift);
ori(at, at, (imm32 & kImm16Mask));
}
jalr(at);
// Emit a nop in the branch delay slot if required.
if (bdslot == PROTECT)
nop();
}
void MacroAssembler::DropAndRet(int drop,
Condition cond,
Register r1,
const Operand& r2) {
// This is a workaround to make sure only one branch instruction is
// generated. It relies on Drop and Ret not creating branches if
// cond == cc_always.
Label skip;
if (cond != cc_always) {
Branch(&skip, NegateCondition(cond), r1, r2);
}
Drop(drop);
Ret();
if (cond != cc_always) {
bind(&skip);
}
}
void MacroAssembler::Drop(int count,
Condition cond,
Register reg,
const Operand& op) {
if (count <= 0) {
return;
}
Label skip;
if (cond != al) {
Branch(&skip, NegateCondition(cond), reg, op);
}
addiu(sp, sp, count * kPointerSize);
if (cond != al) {
bind(&skip);
}
}
void MacroAssembler::Swap(Register reg1,
Register reg2,
Register scratch) {
if (scratch.is(no_reg)) {
Xor(reg1, reg1, Operand(reg2));
Xor(reg2, reg2, Operand(reg1));
Xor(reg1, reg1, Operand(reg2));
} else {
mov(scratch, reg1);
mov(reg1, reg2);
mov(reg2, scratch);
}
}
void MacroAssembler::Call(Label* target) {
BranchAndLink(target);
}
void MacroAssembler::Push(Handle<Object> handle) {
li(at, Operand(handle));
push(at);
}
#ifdef ENABLE_DEBUGGER_SUPPORT
void MacroAssembler::DebugBreak() {
ASSERT(allow_stub_calls());
mov(a0, zero_reg);
li(a1, Operand(ExternalReference(Runtime::kDebugBreak, isolate())));
CEntryStub ces(1);
Call(ces.GetCode(), RelocInfo::DEBUG_BREAK);
}
#endif // ENABLE_DEBUGGER_SUPPORT
// ---------------------------------------------------------------------------
// Exception handling.
void MacroAssembler::PushTryHandler(CodeLocation try_location,
HandlerType type) {
// Adjust this code if not the case.
STATIC_ASSERT(StackHandlerConstants::kSize == 5 * kPointerSize);
STATIC_ASSERT(StackHandlerConstants::kNextOffset == 0 * kPointerSize);
STATIC_ASSERT(StackHandlerConstants::kStateOffset == 1 * kPointerSize);
STATIC_ASSERT(StackHandlerConstants::kContextOffset == 2 * kPointerSize);
STATIC_ASSERT(StackHandlerConstants::kFPOffset == 3 * kPointerSize);
STATIC_ASSERT(StackHandlerConstants::kPCOffset == 4 * kPointerSize);
// The return address is passed in register ra.
if (try_location == IN_JAVASCRIPT) {
if (type == TRY_CATCH_HANDLER) {
li(t0, Operand(StackHandler::TRY_CATCH));
} else {
li(t0, Operand(StackHandler::TRY_FINALLY));
}
// Save the current handler as the next handler.
li(t2, Operand(ExternalReference(Isolate::k_handler_address, isolate())));
lw(t1, MemOperand(t2));
addiu(sp, sp, -StackHandlerConstants::kSize);
sw(ra, MemOperand(sp, StackHandlerConstants::kPCOffset));
sw(fp, MemOperand(sp, StackHandlerConstants::kFPOffset));
sw(cp, MemOperand(sp, StackHandlerConstants::kContextOffset));
sw(t0, MemOperand(sp, StackHandlerConstants::kStateOffset));
sw(t1, MemOperand(sp, StackHandlerConstants::kNextOffset));
// Link this handler as the new current one.
sw(sp, MemOperand(t2));
} else {
// Must preserve a0-a3, and s0 (argv).
ASSERT(try_location == IN_JS_ENTRY);
// The frame pointer does not point to a JS frame so we save NULL
// for fp. We expect the code throwing an exception to check fp
// before dereferencing it to restore the context.
li(t0, Operand(StackHandler::ENTRY));
// Save the current handler as the next handler.
li(t2, Operand(ExternalReference(Isolate::k_handler_address, isolate())));
lw(t1, MemOperand(t2));
ASSERT(Smi::FromInt(0) == 0); // Used for no context.
addiu(sp, sp, -StackHandlerConstants::kSize);
sw(ra, MemOperand(sp, StackHandlerConstants::kPCOffset));
sw(zero_reg, MemOperand(sp, StackHandlerConstants::kFPOffset));
sw(zero_reg, MemOperand(sp, StackHandlerConstants::kContextOffset));
sw(t0, MemOperand(sp, StackHandlerConstants::kStateOffset));
sw(t1, MemOperand(sp, StackHandlerConstants::kNextOffset));
// Link this handler as the new current one.
sw(sp, MemOperand(t2));
}
}
void MacroAssembler::PopTryHandler() {
STATIC_ASSERT(StackHandlerConstants::kNextOffset == 0);
pop(a1);
Addu(sp, sp, Operand(StackHandlerConstants::kSize - kPointerSize));
li(at, Operand(ExternalReference(Isolate::k_handler_address, isolate())));
sw(a1, MemOperand(at));
}
void MacroAssembler::Throw(Register value) {
// v0 is expected to hold the exception.
Move(v0, value);
// Adjust this code if not the case.
STATIC_ASSERT(StackHandlerConstants::kSize == 5 * kPointerSize);
STATIC_ASSERT(StackHandlerConstants::kNextOffset == 0 * kPointerSize);
STATIC_ASSERT(StackHandlerConstants::kStateOffset == 1 * kPointerSize);
STATIC_ASSERT(StackHandlerConstants::kContextOffset == 2 * kPointerSize);
STATIC_ASSERT(StackHandlerConstants::kFPOffset == 3 * kPointerSize);
STATIC_ASSERT(StackHandlerConstants::kPCOffset == 4 * kPointerSize);
// Drop the sp to the top of the handler.
li(a3, Operand(ExternalReference(Isolate::k_handler_address,
isolate())));
lw(sp, MemOperand(a3));
// Restore the next handler.
pop(a2);
sw(a2, MemOperand(a3));
// Restore context and frame pointer, discard state (a3).
MultiPop(a3.bit() | cp.bit() | fp.bit());
// If the handler is a JS frame, restore the context to the frame.
// (a3 == ENTRY) == (fp == 0) == (cp == 0), so we could test any
// of them.
Label done;
Branch(&done, eq, fp, Operand(zero_reg));
sw(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
bind(&done);
#ifdef DEBUG
// When emitting debug_code, set ra as return address for the jump.
// 5 instructions: add: 1, pop: 2, jump: 2.
const int kOffsetRaInstructions = 5;
Label find_ra;
if (emit_debug_code()) {
// Compute ra for the Jump(t9).
const int kOffsetRaBytes = kOffsetRaInstructions * Assembler::kInstrSize;
// This branch-and-link sequence is needed to get the current PC on mips,
// saved to the ra register. Then adjusted for instruction count.
bal(&find_ra); // bal exposes branch-delay.
nop(); // Branch delay slot nop.
bind(&find_ra);
addiu(ra, ra, kOffsetRaBytes);
}
#endif
pop(t9); // 2 instructions: lw, add sp.
Jump(t9); // 2 instructions: jr, nop (in delay slot).
if (emit_debug_code()) {
// Make sure that the expected number of instructions were generated.
ASSERT_EQ(kOffsetRaInstructions,
InstructionsGeneratedSince(&find_ra));
}
}
void MacroAssembler::ThrowUncatchable(UncatchableExceptionType type,
Register value) {
// Adjust this code if not the case.
STATIC_ASSERT(StackHandlerConstants::kSize == 5 * kPointerSize);
STATIC_ASSERT(StackHandlerConstants::kNextOffset == 0 * kPointerSize);
STATIC_ASSERT(StackHandlerConstants::kStateOffset == 1 * kPointerSize);
STATIC_ASSERT(StackHandlerConstants::kContextOffset == 2 * kPointerSize);
STATIC_ASSERT(StackHandlerConstants::kFPOffset == 3 * kPointerSize);
STATIC_ASSERT(StackHandlerConstants::kPCOffset == 4 * kPointerSize);
// v0 is expected to hold the exception.
Move(v0, value);
// Drop sp to the top stack handler.
li(a3, Operand(ExternalReference(Isolate::k_handler_address, isolate())));
lw(sp, MemOperand(a3));
// Unwind the handlers until the ENTRY handler is found.
Label loop, done;
bind(&loop);
// Load the type of the current stack handler.
const int kStateOffset = StackHandlerConstants::kStateOffset;
lw(a2, MemOperand(sp, kStateOffset));
Branch(&done, eq, a2, Operand(StackHandler::ENTRY));
// Fetch the next handler in the list.
const int kNextOffset = StackHandlerConstants::kNextOffset;
lw(sp, MemOperand(sp, kNextOffset));
jmp(&loop);
bind(&done);
// Set the top handler address to next handler past the current ENTRY handler.
pop(a2);
sw(a2, MemOperand(a3));
if (type == OUT_OF_MEMORY) {
// Set external caught exception to false.
ExternalReference external_caught(
Isolate::k_external_caught_exception_address, isolate());
li(a0, Operand(false, RelocInfo::NONE));
li(a2, Operand(external_caught));
sw(a0, MemOperand(a2));
// Set pending exception and v0 to out of memory exception.
Failure* out_of_memory = Failure::OutOfMemoryException();
li(v0, Operand(reinterpret_cast<int32_t>(out_of_memory)));
li(a2, Operand(ExternalReference(Isolate::k_pending_exception_address,
isolate())));
sw(v0, MemOperand(a2));
}
// Stack layout at this point. See also StackHandlerConstants.
// sp -> state (ENTRY)
// cp
// fp
// ra
// Restore context and frame pointer, discard state (r2).
MultiPop(a2.bit() | cp.bit() | fp.bit());
#ifdef DEBUG
// When emitting debug_code, set ra as return address for the jump.
// 5 instructions: add: 1, pop: 2, jump: 2.
const int kOffsetRaInstructions = 5;
Label find_ra;
if (emit_debug_code()) {
// Compute ra for the Jump(t9).
const int kOffsetRaBytes = kOffsetRaInstructions * Assembler::kInstrSize;
// This branch-and-link sequence is needed to get the current PC on mips,
// saved to the ra register. Then adjusted for instruction count.
bal(&find_ra); // bal exposes branch-delay slot.
nop(); // Branch delay slot nop.
bind(&find_ra);
addiu(ra, ra, kOffsetRaBytes);
}
#endif
pop(t9); // 2 instructions: lw, add sp.
Jump(t9); // 2 instructions: jr, nop (in delay slot).
if (emit_debug_code()) {
// Make sure that the expected number of instructions were generated.
ASSERT_EQ(kOffsetRaInstructions,
InstructionsGeneratedSince(&find_ra));
}
}
void MacroAssembler::AllocateInNewSpace(int object_size,
Register result,
Register scratch1,
Register scratch2,
Label* gc_required,
AllocationFlags flags) {
if (!FLAG_inline_new) {
if (emit_debug_code()) {
// Trash the registers to simulate an allocation failure.
li(result, 0x7091);
li(scratch1, 0x7191);
li(scratch2, 0x7291);
}
jmp(gc_required);
return;
}
ASSERT(!result.is(scratch1));
ASSERT(!result.is(scratch2));
ASSERT(!scratch1.is(scratch2));
ASSERT(!scratch1.is(t9));
ASSERT(!scratch2.is(t9));
ASSERT(!result.is(t9));
// Make object size into bytes.
if ((flags & SIZE_IN_WORDS) != 0) {
object_size *= kPointerSize;
}
ASSERT_EQ(0, object_size & kObjectAlignmentMask);
// Check relative positions of allocation top and limit addresses.
// ARM adds additional checks to make sure the ldm instruction can be
// used. On MIPS we don't have ldm so we don't need additional checks either.
ExternalReference new_space_allocation_top =
ExternalReference::new_space_allocation_top_address(isolate());
ExternalReference new_space_allocation_limit =
ExternalReference::new_space_allocation_limit_address(isolate());
intptr_t top =
reinterpret_cast<intptr_t>(new_space_allocation_top.address());
intptr_t limit =
reinterpret_cast<intptr_t>(new_space_allocation_limit.address());
ASSERT((limit - top) == kPointerSize);
// Set up allocation top address and object size registers.
Register topaddr = scratch1;
Register obj_size_reg = scratch2;
li(topaddr, Operand(new_space_allocation_top));
li(obj_size_reg, Operand(object_size));
// This code stores a temporary value in t9.
if ((flags & RESULT_CONTAINS_TOP) == 0) {
// Load allocation top into result and allocation limit into t9.
lw(result, MemOperand(topaddr));
lw(t9, MemOperand(topaddr, kPointerSize));
} else {
if (emit_debug_code()) {
// Assert that result actually contains top on entry. t9 is used
// immediately below so this use of t9 does not cause difference with
// respect to register content between debug and release mode.
lw(t9, MemOperand(topaddr));
Check(eq, "Unexpected allocation top", result, Operand(t9));
}
// Load allocation limit into t9. Result already contains allocation top.
lw(t9, MemOperand(topaddr, limit - top));
}
// Calculate new top and bail out if new space is exhausted. Use result
// to calculate the new top.
Addu(scratch2, result, Operand(obj_size_reg));
Branch(gc_required, Ugreater, scratch2, Operand(t9));
sw(scratch2, MemOperand(topaddr));
// Tag object if requested.
if ((flags & TAG_OBJECT) != 0) {
Addu(result, result, Operand(kHeapObjectTag));
}
}
void MacroAssembler::AllocateInNewSpace(Register object_size,
Register result,
Register scratch1,
Register scratch2,
Label* gc_required,
AllocationFlags flags) {
if (!FLAG_inline_new) {
if (emit_debug_code()) {
// Trash the registers to simulate an allocation failure.
li(result, 0x7091);
li(scratch1, 0x7191);
li(scratch2, 0x7291);
}
jmp(gc_required);
return;
}
ASSERT(!result.is(scratch1));
ASSERT(!result.is(scratch2));
ASSERT(!scratch1.is(scratch2));
ASSERT(!scratch1.is(t9) && !scratch2.is(t9) && !result.is(t9));
// Check relative positions of allocation top and limit addresses.
// ARM adds additional checks to make sure the ldm instruction can be
// used. On MIPS we don't have ldm so we don't need additional checks either.
ExternalReference new_space_allocation_top =
ExternalReference::new_space_allocation_top_address(isolate());
ExternalReference new_space_allocation_limit =
ExternalReference::new_space_allocation_limit_address(isolate());
intptr_t top =
reinterpret_cast<intptr_t>(new_space_allocation_top.address());
intptr_t limit =
reinterpret_cast<intptr_t>(new_space_allocation_limit.address());
ASSERT((limit - top) == kPointerSize);
// Set up allocation top address and object size registers.
Register topaddr = scratch1;
li(topaddr, Operand(new_space_allocation_top));
// This code stores a temporary value in t9.
if ((flags & RESULT_CONTAINS_TOP) == 0) {
// Load allocation top into result and allocation limit into t9.
lw(result, MemOperand(topaddr));
lw(t9, MemOperand(topaddr, kPointerSize));
} else {
if (emit_debug_code()) {
// Assert that result actually contains top on entry. t9 is used
// immediately below so this use of t9 does not cause difference with
// respect to register content between debug and release mode.
lw(t9, MemOperand(topaddr));
Check(eq, "Unexpected allocation top", result, Operand(t9));
}
// Load allocation limit into t9. Result already contains allocation top.
lw(t9, MemOperand(topaddr, limit - top));
}
// Calculate new top and bail out if new space is exhausted. Use result
// to calculate the new top. Object size may be in words so a shift is
// required to get the number of bytes.
if ((flags & SIZE_IN_WORDS) != 0) {
sll(scratch2, object_size, kPointerSizeLog2);
Addu(scratch2, result, scratch2);
} else {
Addu(scratch2, result, Operand(object_size));
}
Branch(gc_required, Ugreater, scratch2, Operand(t9));
// Update allocation top. result temporarily holds the new top.
if (emit_debug_code()) {
And(t9, scratch2, Operand(kObjectAlignmentMask));
Check(eq, "Unaligned allocation in new space", t9, Operand(zero_reg));
}
sw(scratch2, MemOperand(topaddr));
// Tag object if requested.
if ((flags & TAG_OBJECT) != 0) {
Addu(result, result, Operand(kHeapObjectTag));
}
}
void MacroAssembler::UndoAllocationInNewSpace(Register object,
Register scratch) {
ExternalReference new_space_allocation_top =
ExternalReference::new_space_allocation_top_address(isolate());
// Make sure the object has no tag before resetting top.
And(object, object, Operand(~kHeapObjectTagMask));
#ifdef DEBUG
// Check that the object un-allocated is below the current top.
li(scratch, Operand(new_space_allocation_top));
lw(scratch, MemOperand(scratch));
Check(less, "Undo allocation of non allocated memory",
object, Operand(scratch));
#endif
// Write the address of the object to un-allocate as the current top.
li(scratch, Operand(new_space_allocation_top));
sw(object, MemOperand(scratch));
}
void MacroAssembler::AllocateTwoByteString(Register result,
Register length,
Register scratch1,
Register scratch2,
Register scratch3,
Label* gc_required) {
// Calculate the number of bytes needed for the characters in the string while
// observing object alignment.
ASSERT((SeqTwoByteString::kHeaderSize & kObjectAlignmentMask) == 0);
sll(scratch1, length, 1); // Length in bytes, not chars.
addiu(scratch1, scratch1,
kObjectAlignmentMask + SeqTwoByteString::kHeaderSize);
And(scratch1, scratch1, Operand(~kObjectAlignmentMask));
// Allocate two-byte string in new space.
AllocateInNewSpace(scratch1,
result,
scratch2,
scratch3,
gc_required,
TAG_OBJECT);
// Set the map, length and hash field.
InitializeNewString(result,
length,
Heap::kStringMapRootIndex,
scratch1,
scratch2);
}
void MacroAssembler::AllocateAsciiString(Register result,
Register length,
Register scratch1,
Register scratch2,
Register scratch3,
Label* gc_required) {
// Calculate the number of bytes needed for the characters in the string
// while observing object alignment.
ASSERT((SeqAsciiString::kHeaderSize & kObjectAlignmentMask) == 0);
ASSERT(kCharSize == 1);
addiu(scratch1, length, kObjectAlignmentMask + SeqAsciiString::kHeaderSize);
And(scratch1, scratch1, Operand(~kObjectAlignmentMask));
// Allocate ASCII string in new space.
AllocateInNewSpace(scratch1,
result,
scratch2,
scratch3,
gc_required,
TAG_OBJECT);
// Set the map, length and hash field.
InitializeNewString(result,
length,
Heap::kAsciiStringMapRootIndex,
scratch1,
scratch2);
}
void MacroAssembler::AllocateTwoByteConsString(Register result,
Register length,
Register scratch1,
Register scratch2,
Label* gc_required) {
AllocateInNewSpace(ConsString::kSize,
result,
scratch1,
scratch2,
gc_required,
TAG_OBJECT);
InitializeNewString(result,
length,
Heap::kConsStringMapRootIndex,
scratch1,
scratch2);
}
void MacroAssembler::AllocateAsciiConsString(Register result,
Register length,
Register scratch1,
Register scratch2,
Label* gc_required) {
AllocateInNewSpace(ConsString::kSize,
result,
scratch1,
scratch2,
gc_required,
TAG_OBJECT);
InitializeNewString(result,
length,
Heap::kConsAsciiStringMapRootIndex,
scratch1,
scratch2);
}
// Allocates a heap number or jumps to the label if the young space is full and
// a scavenge is needed.
void MacroAssembler::AllocateHeapNumber(Register result,
Register scratch1,
Register scratch2,
Register heap_number_map,
Label* need_gc) {
// Allocate an object in the heap for the heap number and tag it as a heap
// object.
AllocateInNewSpace(HeapNumber::kSize,
result,
scratch1,
scratch2,
need_gc,
TAG_OBJECT);
// Store heap number map in the allocated object.
AssertRegisterIsRoot(heap_number_map, Heap::kHeapNumberMapRootIndex);
sw(heap_number_map, FieldMemOperand(result, HeapObject::kMapOffset));
}
void MacroAssembler::AllocateHeapNumberWithValue(Register result,
FPURegister value,
Register scratch1,
Register scratch2,
Label* gc_required) {
LoadRoot(t8, Heap::kHeapNumberMapRootIndex);
AllocateHeapNumber(result, scratch1, scratch2, t8, gc_required);
sdc1(value, FieldMemOperand(result, HeapNumber::kValueOffset));
}
// Copies a fixed number of fields of heap objects from src to dst.
void MacroAssembler::CopyFields(Register dst,
Register src,
RegList temps,
int field_count) {
ASSERT((temps & dst.bit()) == 0);
ASSERT((temps & src.bit()) == 0);
// Primitive implementation using only one temporary register.
Register tmp = no_reg;
// Find a temp register in temps list.
for (int i = 0; i < kNumRegisters; i++) {
if ((temps & (1 << i)) != 0) {
tmp.code_ = i;
break;
}
}
ASSERT(!tmp.is(no_reg));
for (int i = 0; i < field_count; i++) {
lw(tmp, FieldMemOperand(src, i * kPointerSize));
sw(tmp, FieldMemOperand(dst, i * kPointerSize));
}
}
void MacroAssembler::CopyBytes(Register src,
Register dst,
Register length,
Register scratch) {
Label align_loop, align_loop_1, word_loop, byte_loop, byte_loop_1, done;
// Align src before copying in word size chunks.
bind(&align_loop);
Branch(&done, eq, length, Operand(zero_reg));
bind(&align_loop_1);
And(scratch, src, kPointerSize - 1);
Branch(&word_loop, eq, scratch, Operand(zero_reg));
lbu(scratch, MemOperand(src));
Addu(src, src, 1);
sb(scratch, MemOperand(dst));
Addu(dst, dst, 1);
Subu(length, length, Operand(1));
Branch(&byte_loop_1, ne, length, Operand(zero_reg));
// Copy bytes in word size chunks.
bind(&word_loop);
if (emit_debug_code()) {
And(scratch, src, kPointerSize - 1);
Assert(eq, "Expecting alignment for CopyBytes",
scratch, Operand(zero_reg));
}
Branch(&byte_loop, lt, length, Operand(kPointerSize));
lw(scratch, MemOperand(src));
Addu(src, src, kPointerSize);
// TODO(kalmard) check if this can be optimized to use sw in most cases.
// Can't use unaligned access - copy byte by byte.
sb(scratch, MemOperand(dst, 0));
srl(scratch, scratch, 8);
sb(scratch, MemOperand(dst, 1));
srl(scratch, scratch, 8);
sb(scratch, MemOperand(dst, 2));
srl(scratch, scratch, 8);
sb(scratch, MemOperand(dst, 3));
Addu(dst, dst, 4);
Subu(length, length, Operand(kPointerSize));
Branch(&word_loop);
// Copy the last bytes if any left.
bind(&byte_loop);
Branch(&done, eq, length, Operand(zero_reg));
bind(&byte_loop_1);
lbu(scratch, MemOperand(src));
Addu(src, src, 1);
sb(scratch, MemOperand(dst));
Addu(dst, dst, 1);
Subu(length, length, Operand(1));
Branch(&byte_loop_1, ne, length, Operand(zero_reg));
bind(&done);
}
void MacroAssembler::CheckFastElements(Register map,
Register scratch,
Label* fail) {
STATIC_ASSERT(JSObject::FAST_ELEMENTS == 0);
lbu(scratch, FieldMemOperand(map, Map::kBitField2Offset));
Branch(fail, hi, scratch, Operand(Map::kMaximumBitField2FastElementValue));
}
void MacroAssembler::CheckMap(Register obj,
Register scratch,
Handle<Map> map,
Label* fail,
SmiCheckType smi_check_type) {
if (smi_check_type == DO_SMI_CHECK) {
JumpIfSmi(obj, fail);
}
lw(scratch, FieldMemOperand(obj, HeapObject::kMapOffset));
li(at, Operand(map));
Branch(fail, ne, scratch, Operand(at));
}
void MacroAssembler::DispatchMap(Register obj,
Register scratch,
Handle<Map> map,
Handle<Code> success,
SmiCheckType smi_check_type) {
Label fail;
if (smi_check_type == DO_SMI_CHECK) {
JumpIfSmi(obj, &fail);
}
lw(scratch, FieldMemOperand(obj, HeapObject::kMapOffset));
Jump(success, RelocInfo::CODE_TARGET, eq, scratch, Operand(map));
bind(&fail);
}
void MacroAssembler::CheckMap(Register obj,
Register scratch,
Heap::RootListIndex index,
Label* fail,
SmiCheckType smi_check_type) {
if (smi_check_type == DO_SMI_CHECK) {
JumpIfSmi(obj, fail);
}
lw(scratch, FieldMemOperand(obj, HeapObject::kMapOffset));
LoadRoot(at, index);
Branch(fail, ne, scratch, Operand(at));
}
void MacroAssembler::GetCFunctionDoubleResult(const DoubleRegister dst) {
CpuFeatures::Scope scope(FPU);
if (IsMipsSoftFloatABI) {
Move(dst, v0, v1);
} else {
Move(dst, f0); // Reg f0 is o32 ABI FP return value.
}
}
void MacroAssembler::SetCallCDoubleArguments(DoubleRegister dreg) {
CpuFeatures::Scope scope(FPU);
if (!IsMipsSoftFloatABI) {
Move(f12, dreg);
} else {
Move(a0, a1, dreg);
}
}
void MacroAssembler::SetCallCDoubleArguments(DoubleRegister dreg1,
DoubleRegister dreg2) {
CpuFeatures::Scope scope(FPU);
if (!IsMipsSoftFloatABI) {
if (dreg2.is(f12)) {
ASSERT(!dreg1.is(f14));
Move(f14, dreg2);
Move(f12, dreg1);
} else {
Move(f12, dreg1);
Move(f14, dreg2);
}
} else {
Move(a0, a1, dreg1);
Move(a2, a3, dreg2);
}
}
void MacroAssembler::SetCallCDoubleArguments(DoubleRegister dreg,
Register reg) {
CpuFeatures::Scope scope(FPU);
if (!IsMipsSoftFloatABI) {
Move(f12, dreg);
Move(a2, reg);
} else {
Move(a2, reg);
Move(a0, a1, dreg);
}
}
void MacroAssembler::SetCallKind(Register dst, CallKind call_kind) {
// This macro takes the dst register to make the code more readable
// at the call sites. However, the dst register has to be t1 to
// follow the calling convention which requires the call type to be
// in t1.
ASSERT(dst.is(t1));
if (call_kind == CALL_AS_FUNCTION) {
li(dst, Operand(Smi::FromInt(1)));
} else {
li(dst, Operand(Smi::FromInt(0)));
}
}
// -----------------------------------------------------------------------------
// JavaScript invokes.
void MacroAssembler::InvokePrologue(const ParameterCount& expected,
const ParameterCount& actual,
Handle<Code> code_constant,
Register code_reg,
Label* done,
InvokeFlag flag,
const CallWrapper& call_wrapper,
CallKind call_kind) {
bool definitely_matches = false;
Label regular_invoke;
// Check whether the expected and actual arguments count match. If not,
// setup registers according to contract with ArgumentsAdaptorTrampoline:
// a0: actual arguments count
// a1: function (passed through to callee)
// a2: expected arguments count
// a3: callee code entry
// The code below is made a lot easier because the calling code already sets
// up actual and expected registers according to the contract if values are
// passed in registers.
ASSERT(actual.is_immediate() || actual.reg().is(a0));
ASSERT(expected.is_immediate() || expected.reg().is(a2));
ASSERT((!code_constant.is_null() && code_reg.is(no_reg)) || code_reg.is(a3));
if (expected.is_immediate()) {
ASSERT(actual.is_immediate());
if (expected.immediate() == actual.immediate()) {
definitely_matches = true;
} else {
li(a0, Operand(actual.immediate()));
const int sentinel = SharedFunctionInfo::kDontAdaptArgumentsSentinel;
if (expected.immediate() == sentinel) {
// Don't worry about adapting arguments for builtins that
// don't want that done. Skip adaption code by making it look
// like we have a match between expected and actual number of
// arguments.
definitely_matches = true;
} else {
li(a2, Operand(expected.immediate()));
}
}
} else if (actual.is_immediate()) {
Branch(&regular_invoke, eq, expected.reg(), Operand(actual.immediate()));
li(a0, Operand(actual.immediate()));
} else {
Branch(&regular_invoke, eq, expected.reg(), Operand(actual.reg()));
}
if (!definitely_matches) {
if (!code_constant.is_null()) {
li(a3, Operand(code_constant));
addiu(a3, a3, Code::kHeaderSize - kHeapObjectTag);
}
Handle<Code> adaptor =
isolate()->builtins()->ArgumentsAdaptorTrampoline();
if (flag == CALL_FUNCTION) {
call_wrapper.BeforeCall(CallSize(adaptor));
SetCallKind(t1, call_kind);
Call(adaptor);
call_wrapper.AfterCall();
jmp(done);
} else {
SetCallKind(t1, call_kind);
Jump(adaptor, RelocInfo::CODE_TARGET);
}
bind(&regular_invoke);
}
}
void MacroAssembler::InvokeCode(Register code,
const ParameterCount& expected,
const ParameterCount& actual,
InvokeFlag flag,
const CallWrapper& call_wrapper,
CallKind call_kind) {
Label done;
InvokePrologue(expected, actual, Handle<Code>::null(), code, &done, flag,
call_wrapper, call_kind);
if (flag == CALL_FUNCTION) {
SetCallKind(t1, call_kind);
Call(code);
} else {
ASSERT(flag == JUMP_FUNCTION);
SetCallKind(t1, call_kind);
Jump(code);
}
// Continue here if InvokePrologue does handle the invocation due to
// mismatched parameter counts.
bind(&done);
}
void MacroAssembler::InvokeCode(Handle<Code> code,
const ParameterCount& expected,
const ParameterCount& actual,
RelocInfo::Mode rmode,
InvokeFlag flag,
CallKind call_kind) {
Label done;
InvokePrologue(expected, actual, code, no_reg, &done, flag,
NullCallWrapper(), call_kind);
if (flag == CALL_FUNCTION) {
SetCallKind(t1, call_kind);
Call(code, rmode);
} else {
SetCallKind(t1, call_kind);
Jump(code, rmode);
}
// Continue here if InvokePrologue does handle the invocation due to
// mismatched parameter counts.
bind(&done);
}
void MacroAssembler::InvokeFunction(Register function,
const ParameterCount& actual,
InvokeFlag flag,
const CallWrapper& call_wrapper,
CallKind call_kind) {
// Contract with called JS functions requires that function is passed in a1.
ASSERT(function.is(a1));
Register expected_reg = a2;
Register code_reg = a3;
lw(code_reg, FieldMemOperand(a1, JSFunction::kSharedFunctionInfoOffset));
lw(cp, FieldMemOperand(a1, JSFunction::kContextOffset));
lw(expected_reg,
FieldMemOperand(code_reg,
SharedFunctionInfo::kFormalParameterCountOffset));
sra(expected_reg, expected_reg, kSmiTagSize);
lw(code_reg, FieldMemOperand(a1, JSFunction::kCodeEntryOffset));
ParameterCount expected(expected_reg);
InvokeCode(code_reg, expected, actual, flag, call_wrapper, call_kind);
}
void MacroAssembler::InvokeFunction(JSFunction* function,
const ParameterCount& actual,
InvokeFlag flag,
CallKind call_kind) {
ASSERT(function->is_compiled());
// Get the function and setup the context.
li(a1, Operand(Handle<JSFunction>(function)));
lw(cp, FieldMemOperand(a1, JSFunction::kContextOffset));
// Invoke the cached code.
Handle<Code> code(function->code());
ParameterCount expected(function->shared()->formal_parameter_count());
if (V8::UseCrankshaft()) {
UNIMPLEMENTED_MIPS();
} else {
InvokeCode(code, expected, actual, RelocInfo::CODE_TARGET, flag, call_kind);
}
}
void MacroAssembler::IsObjectJSObjectType(Register heap_object,
Register map,
Register scratch,
Label* fail) {
lw(map, FieldMemOperand(heap_object, HeapObject::kMapOffset));
IsInstanceJSObjectType(map, scratch, fail);
}
void MacroAssembler::IsInstanceJSObjectType(Register map,
Register scratch,
Label* fail) {
lbu(scratch, FieldMemOperand(map, Map::kInstanceTypeOffset));
Branch(fail, lt, scratch, Operand(FIRST_NONCALLABLE_SPEC_OBJECT_TYPE));
Branch(fail, gt, scratch, Operand(LAST_NONCALLABLE_SPEC_OBJECT_TYPE));
}
void MacroAssembler::IsObjectJSStringType(Register object,
Register scratch,
Label* fail) {
ASSERT(kNotStringTag != 0);
lw(scratch, FieldMemOperand(object, HeapObject::kMapOffset));
lbu(scratch, FieldMemOperand(scratch, Map::kInstanceTypeOffset));
And(scratch, scratch, Operand(kIsNotStringMask));
Branch(fail, ne, scratch, Operand(zero_reg));
}
// ---------------------------------------------------------------------------
// Support functions.
void MacroAssembler::TryGetFunctionPrototype(Register function,
Register result,
Register scratch,
Label* miss) {
// Check that the receiver isn't a smi.
JumpIfSmi(function, miss);
// Check that the function really is a function. Load map into result reg.
GetObjectType(function, result, scratch);
Branch(miss, ne, scratch, Operand(JS_FUNCTION_TYPE));
// Make sure that the function has an instance prototype.
Label non_instance;
lbu(scratch, FieldMemOperand(result, Map::kBitFieldOffset));
And(scratch, scratch, Operand(1 << Map::kHasNonInstancePrototype));
Branch(&non_instance, ne, scratch, Operand(zero_reg));
// Get the prototype or initial map from the function.
lw(result,
FieldMemOperand(function, JSFunction::kPrototypeOrInitialMapOffset));
// If the prototype or initial map is the hole, don't return it and
// simply miss the cache instead. This will allow us to allocate a
// prototype object on-demand in the runtime system.
LoadRoot(t8, Heap::kTheHoleValueRootIndex);
Branch(miss, eq, result, Operand(t8));
// If the function does not have an initial map, we're done.
Label done;
GetObjectType(result, scratch, scratch);
Branch(&done, ne, scratch, Operand(MAP_TYPE));
// Get the prototype from the initial map.
lw(result, FieldMemOperand(result, Map::kPrototypeOffset));
jmp(&done);
// Non-instance prototype: Fetch prototype from constructor field
// in initial map.
bind(&non_instance);
lw(result, FieldMemOperand(result, Map::kConstructorOffset));
// All done.
bind(&done);
}
void MacroAssembler::GetObjectType(Register object,
Register map,
Register type_reg) {
lw(map, FieldMemOperand(object, HeapObject::kMapOffset));
lbu(type_reg, FieldMemOperand(map, Map::kInstanceTypeOffset));
}
// -----------------------------------------------------------------------------
// Runtime calls.
void MacroAssembler::CallStub(CodeStub* stub, Condition cond,
Register r1, const Operand& r2) {
ASSERT(allow_stub_calls()); // Stub calls are not allowed in some stubs.
Call(stub->GetCode(), RelocInfo::CODE_TARGET, kNoASTId, cond, r1, r2);
}
MaybeObject* MacroAssembler::TryCallStub(CodeStub* stub, Condition cond,
Register r1, const Operand& r2) {
ASSERT(allow_stub_calls()); // Stub calls are not allowed in some stubs.
Object* result;
{ MaybeObject* maybe_result = stub->TryGetCode();
if (!maybe_result->ToObject(&result)) return maybe_result;
}
Call(Handle<Code>(Code::cast(result)), RelocInfo::CODE_TARGET,
kNoASTId, cond, r1, r2);
return result;
}
void MacroAssembler::TailCallStub(CodeStub* stub) {
ASSERT(allow_stub_calls()); // Stub calls are not allowed in some stubs.
Jump(stub->GetCode(), RelocInfo::CODE_TARGET);
}
MaybeObject* MacroAssembler::TryTailCallStub(CodeStub* stub,
Condition cond,
Register r1,
const Operand& r2) {
ASSERT(allow_stub_calls()); // Stub calls are not allowed in some stubs.
Object* result;
{ MaybeObject* maybe_result = stub->TryGetCode();
if (!maybe_result->ToObject(&result)) return maybe_result;
}
Jump(Handle<Code>(Code::cast(result)), RelocInfo::CODE_TARGET, cond, r1, r2);
return result;
}
static int AddressOffset(ExternalReference ref0, ExternalReference ref1) {
return ref0.address() - ref1.address();
}
MaybeObject* MacroAssembler::TryCallApiFunctionAndReturn(
ExternalReference function, int stack_space) {
ExternalReference next_address =
ExternalReference::handle_scope_next_address();
const int kNextOffset = 0;
const int kLimitOffset = AddressOffset(
ExternalReference::handle_scope_limit_address(),
next_address);
const int kLevelOffset = AddressOffset(
ExternalReference::handle_scope_level_address(),
next_address);
// Allocate HandleScope in callee-save registers.
li(s3, Operand(next_address));
lw(s0, MemOperand(s3, kNextOffset));
lw(s1, MemOperand(s3, kLimitOffset));
lw(s2, MemOperand(s3, kLevelOffset));
Addu(s2, s2, Operand(1));
sw(s2, MemOperand(s3, kLevelOffset));
// The O32 ABI requires us to pass a pointer in a0 where the returned struct
// (4 bytes) will be placed. This is also built into the Simulator.
// Set up the pointer to the returned value (a0). It was allocated in
// EnterExitFrame.
addiu(a0, fp, ExitFrameConstants::kStackSpaceOffset);
// Native call returns to the DirectCEntry stub which redirects to the
// return address pushed on stack (could have moved after GC).
// DirectCEntry stub itself is generated early and never moves.
DirectCEntryStub stub;
stub.GenerateCall(this, function);
// As mentioned above, on MIPS a pointer is returned - we need to dereference
// it to get the actual return value (which is also a pointer).
lw(v0, MemOperand(v0));
Label promote_scheduled_exception;
Label delete_allocated_handles;
Label leave_exit_frame;
// If result is non-zero, dereference to get the result value
// otherwise set it to undefined.
Label skip;
LoadRoot(a0, Heap::kUndefinedValueRootIndex);
Branch(&skip, eq, v0, Operand(zero_reg));
lw(a0, MemOperand(v0));
bind(&skip);
mov(v0, a0);
// No more valid handles (the result handle was the last one). Restore
// previous handle scope.
sw(s0, MemOperand(s3, kNextOffset));
if (emit_debug_code()) {
lw(a1, MemOperand(s3, kLevelOffset));
Check(eq, "Unexpected level after return from api call", a1, Operand(s2));
}
Subu(s2, s2, Operand(1));
sw(s2, MemOperand(s3, kLevelOffset));
lw(at, MemOperand(s3, kLimitOffset));
Branch(&delete_allocated_handles, ne, s1, Operand(at));
// Check if the function scheduled an exception.
bind(&leave_exit_frame);
LoadRoot(t0, Heap::kTheHoleValueRootIndex);
li(at, Operand(ExternalReference::scheduled_exception_address(isolate())));
lw(t1, MemOperand(at));
Branch(&promote_scheduled_exception, ne, t0, Operand(t1));
li(s0, Operand(stack_space));
LeaveExitFrame(false, s0);
Ret();
bind(&promote_scheduled_exception);
MaybeObject* result = TryTailCallExternalReference(
ExternalReference(Runtime::kPromoteScheduledException, isolate()), 0, 1);
if (result->IsFailure()) {
return result;
}
// HandleScope limit has changed. Delete allocated extensions.
bind(&delete_allocated_handles);
sw(s1, MemOperand(s3, kLimitOffset));
mov(s0, v0);
mov(a0, v0);
PrepareCallCFunction(1, s1);
li(a0, Operand(ExternalReference::isolate_address()));
CallCFunction(ExternalReference::delete_handle_scope_extensions(isolate()),
1);
mov(v0, s0);
jmp(&leave_exit_frame);
return result;
}
void MacroAssembler::IllegalOperation(int num_arguments) {
if (num_arguments > 0) {
addiu(sp, sp, num_arguments * kPointerSize);
}
LoadRoot(v0, Heap::kUndefinedValueRootIndex);
}
void MacroAssembler::IndexFromHash(Register hash,
Register index) {
// If the hash field contains an array index pick it out. The assert checks
// that the constants for the maximum number of digits for an array index
// cached in the hash field and the number of bits reserved for it does not
// conflict.
ASSERT(TenToThe(String::kMaxCachedArrayIndexLength) <
(1 << String::kArrayIndexValueBits));
// We want the smi-tagged index in key. kArrayIndexValueMask has zeros in
// the low kHashShift bits.
STATIC_ASSERT(kSmiTag == 0);
Ext(hash, hash, String::kHashShift, String::kArrayIndexValueBits);
sll(index, hash, kSmiTagSize);
}
void MacroAssembler::ObjectToDoubleFPURegister(Register object,
FPURegister result,
Register scratch1,
Register scratch2,
Register heap_number_map,
Label* not_number,
ObjectToDoubleFlags flags) {
Label done;
if ((flags & OBJECT_NOT_SMI) == 0) {
Label not_smi;
JumpIfNotSmi(object, &not_smi);
// Remove smi tag and convert to double.
sra(scratch1, object, kSmiTagSize);
mtc1(scratch1, result);
cvt_d_w(result, result);
Branch(&done);
bind(&not_smi);
}
// Check for heap number and load double value from it.
lw(scratch1, FieldMemOperand(object, HeapObject::kMapOffset));
Branch(not_number, ne, scratch1, Operand(heap_number_map));
if ((flags & AVOID_NANS_AND_INFINITIES) != 0) {
// If exponent is all ones the number is either a NaN or +/-Infinity.
Register exponent = scratch1;
Register mask_reg = scratch2;
lw(exponent, FieldMemOperand(object, HeapNumber::kExponentOffset));
li(mask_reg, HeapNumber::kExponentMask);
And(exponent, exponent, mask_reg);
Branch(not_number, eq, exponent, Operand(mask_reg));
}
ldc1(result, FieldMemOperand(object, HeapNumber::kValueOffset));
bind(&done);
}
void MacroAssembler::SmiToDoubleFPURegister(Register smi,
FPURegister value,
Register scratch1) {
sra(scratch1, smi, kSmiTagSize);
mtc1(scratch1, value);
cvt_d_w(value, value);
}
void MacroAssembler::AdduAndCheckForOverflow(Register dst,
Register left,
Register right,
Register overflow_dst,
Register scratch) {
ASSERT(!dst.is(overflow_dst));
ASSERT(!dst.is(scratch));
ASSERT(!overflow_dst.is(scratch));
ASSERT(!overflow_dst.is(left));
ASSERT(!overflow_dst.is(right));
ASSERT(!left.is(right));
if (dst.is(left)) {
mov(scratch, left); // Preserve left.
addu(dst, left, right); // Left is overwritten.
xor_(scratch, dst, scratch); // Original left.
xor_(overflow_dst, dst, right);
and_(overflow_dst, overflow_dst, scratch);
} else if (dst.is(right)) {
mov(scratch, right); // Preserve right.
addu(dst, left, right); // Right is overwritten.
xor_(scratch, dst, scratch); // Original right.
xor_(overflow_dst, dst, left);
and_(overflow_dst, overflow_dst, scratch);
} else {
addu(dst, left, right);
xor_(overflow_dst, dst, left);
xor_(scratch, dst, right);
and_(overflow_dst, scratch, overflow_dst);
}
}
void MacroAssembler::SubuAndCheckForOverflow(Register dst,
Register left,
Register right,
Register overflow_dst,
Register scratch) {
ASSERT(!dst.is(overflow_dst));
ASSERT(!dst.is(scratch));
ASSERT(!overflow_dst.is(scratch));
ASSERT(!overflow_dst.is(left));
ASSERT(!overflow_dst.is(right));
ASSERT(!left.is(right));
ASSERT(!scratch.is(left));
ASSERT(!scratch.is(right));
if (dst.is(left)) {
mov(scratch, left); // Preserve left.
subu(dst, left, right); // Left is overwritten.
xor_(overflow_dst, dst, scratch); // scratch is original left.
xor_(scratch, scratch, right); // scratch is original left.
and_(overflow_dst, scratch, overflow_dst);
} else if (dst.is(right)) {
mov(scratch, right); // Preserve right.
subu(dst, left, right); // Right is overwritten.
xor_(overflow_dst, dst, left);
xor_(scratch, left, scratch); // Original right.
and_(overflow_dst, scratch, overflow_dst);
} else {
subu(dst, left, right);
xor_(overflow_dst, dst, left);
xor_(scratch, left, right);
and_(overflow_dst, scratch, overflow_dst);
}
}
void MacroAssembler::CallRuntime(const Runtime::Function* f,
int num_arguments) {
// All parameters are on the stack. v0 has the return value after call.
// If the expected number of arguments of the runtime function is
// constant, we check that the actual number of arguments match the
// expectation.
if (f->nargs >= 0 && f->nargs != num_arguments) {
IllegalOperation(num_arguments);
return;
}
// TODO(1236192): Most runtime routines don't need the number of
// arguments passed in because it is constant. At some point we
// should remove this need and make the runtime routine entry code
// smarter.
li(a0, num_arguments);
li(a1, Operand(ExternalReference(f, isolate())));
CEntryStub stub(1);
CallStub(&stub);
}
void MacroAssembler::CallRuntimeSaveDoubles(Runtime::FunctionId id) {
const Runtime::Function* function = Runtime::FunctionForId(id);
li(a0, Operand(function->nargs));
li(a1, Operand(ExternalReference(function, isolate())));
CEntryStub stub(1);
stub.SaveDoubles();
CallStub(&stub);
}
void MacroAssembler::CallRuntime(Runtime::FunctionId fid, int num_arguments) {
CallRuntime(Runtime::FunctionForId(fid), num_arguments);
}
void MacroAssembler::CallExternalReference(const ExternalReference& ext,
int num_arguments) {
li(a0, Operand(num_arguments));
li(a1, Operand(ext));
CEntryStub stub(1);
CallStub(&stub);
}
void MacroAssembler::TailCallExternalReference(const ExternalReference& ext,
int num_arguments,
int result_size) {
// TODO(1236192): Most runtime routines don't need the number of
// arguments passed in because it is constant. At some point we
// should remove this need and make the runtime routine entry code
// smarter.
li(a0, Operand(num_arguments));
JumpToExternalReference(ext);
}
MaybeObject* MacroAssembler::TryTailCallExternalReference(
const ExternalReference& ext, int num_arguments, int result_size) {
// TODO(1236192): Most runtime routines don't need the number of
// arguments passed in because it is constant. At some point we
// should remove this need and make the runtime routine entry code
// smarter.
li(a0, num_arguments);
return TryJumpToExternalReference(ext);
}
void MacroAssembler::TailCallRuntime(Runtime::FunctionId fid,
int num_arguments,
int result_size) {
TailCallExternalReference(ExternalReference(fid, isolate()),
num_arguments,
result_size);
}
void MacroAssembler::JumpToExternalReference(const ExternalReference& builtin) {
li(a1, Operand(builtin));
CEntryStub stub(1);
Jump(stub.GetCode(), RelocInfo::CODE_TARGET);
}
MaybeObject* MacroAssembler::TryJumpToExternalReference(
const ExternalReference& builtin) {
li(a1, Operand(builtin));
CEntryStub stub(1);
return TryTailCallStub(&stub);
}
void MacroAssembler::InvokeBuiltin(Builtins::JavaScript id,
InvokeFlag flag,
const CallWrapper& call_wrapper) {
GetBuiltinEntry(t9, id);
if (flag == CALL_FUNCTION) {
call_wrapper.BeforeCall(CallSize(t9));
SetCallKind(t1, CALL_AS_METHOD);
Call(t9);
call_wrapper.AfterCall();
} else {
ASSERT(flag == JUMP_FUNCTION);
SetCallKind(t1, CALL_AS_METHOD);
Jump(t9);
}
}
void MacroAssembler::GetBuiltinFunction(Register target,
Builtins::JavaScript id) {
// Load the builtins object into target register.
lw(target, MemOperand(cp, Context::SlotOffset(Context::GLOBAL_INDEX)));
lw(target, FieldMemOperand(target, GlobalObject::kBuiltinsOffset));
// Load the JavaScript builtin function from the builtins object.
lw(target, FieldMemOperand(target,
JSBuiltinsObject::OffsetOfFunctionWithId(id)));
}
void MacroAssembler::GetBuiltinEntry(Register target, Builtins::JavaScript id) {
ASSERT(!target.is(a1));
GetBuiltinFunction(a1, id);
// Load the code entry point from the builtins object.
lw(target, FieldMemOperand(a1, JSFunction::kCodeEntryOffset));
}
void MacroAssembler::SetCounter(StatsCounter* counter, int value,
Register scratch1, Register scratch2) {
if (FLAG_native_code_counters && counter->Enabled()) {
li(scratch1, Operand(value));
li(scratch2, Operand(ExternalReference(counter)));
sw(scratch1, MemOperand(scratch2));
}
}
void MacroAssembler::IncrementCounter(StatsCounter* counter, int value,
Register scratch1, Register scratch2) {
ASSERT(value > 0);
if (FLAG_native_code_counters && counter->Enabled()) {
li(scratch2, Operand(ExternalReference(counter)));
lw(scratch1, MemOperand(scratch2));
Addu(scratch1, scratch1, Operand(value));
sw(scratch1, MemOperand(scratch2));
}
}
void MacroAssembler::DecrementCounter(StatsCounter* counter, int value,
Register scratch1, Register scratch2) {
ASSERT(value > 0);
if (FLAG_native_code_counters && counter->Enabled()) {
li(scratch2, Operand(ExternalReference(counter)));
lw(scratch1, MemOperand(scratch2));
Subu(scratch1, scratch1, Operand(value));
sw(scratch1, MemOperand(scratch2));
}
}
// -----------------------------------------------------------------------------
// Debugging.
void MacroAssembler::Assert(Condition cc, const char* msg,
Register rs, Operand rt) {
if (emit_debug_code())
Check(cc, msg, rs, rt);
}
void MacroAssembler::AssertRegisterIsRoot(Register reg,
Heap::RootListIndex index) {
if (emit_debug_code()) {
LoadRoot(at, index);
Check(eq, "Register did not match expected root", reg, Operand(at));
}
}
void MacroAssembler::AssertFastElements(Register elements) {
if (emit_debug_code()) {
ASSERT(!elements.is(at));
Label ok;
push(elements);
lw(elements, FieldMemOperand(elements, HeapObject::kMapOffset));
LoadRoot(at, Heap::kFixedArrayMapRootIndex);
Branch(&ok, eq, elements, Operand(at));
LoadRoot(at, Heap::kFixedDoubleArrayMapRootIndex);
Branch(&ok, eq, elements, Operand(at));
LoadRoot(at, Heap::kFixedCOWArrayMapRootIndex);
Branch(&ok, eq, elements, Operand(at));
Abort("JSObject with fast elements map has slow elements");
bind(&ok);
pop(elements);
}
}
void MacroAssembler::Check(Condition cc, const char* msg,
Register rs, Operand rt) {
Label L;
Branch(&L, cc, rs, rt);
Abort(msg);
// Will not return here.
bind(&L);
}
void MacroAssembler::Abort(const char* msg) {
Label abort_start;
bind(&abort_start);
// We want to pass the msg string like a smi to avoid GC
// problems, however msg is not guaranteed to be aligned
// properly. Instead, we pass an aligned pointer that is
// a proper v8 smi, but also pass the alignment difference
// from the real pointer as a smi.
intptr_t p1 = reinterpret_cast<intptr_t>(msg);
intptr_t p0 = (p1 & ~kSmiTagMask) + kSmiTag;
ASSERT(reinterpret_cast<Object*>(p0)->IsSmi());
#ifdef DEBUG
if (msg != NULL) {
RecordComment("Abort message: ");
RecordComment(msg);
}
#endif
// Disable stub call restrictions to always allow calls to abort.
AllowStubCallsScope allow_scope(this, true);
li(a0, Operand(p0));
push(a0);
li(a0, Operand(Smi::FromInt(p1 - p0)));
push(a0);
CallRuntime(Runtime::kAbort, 2);
// Will not return here.
if (is_trampoline_pool_blocked()) {
// If the calling code cares about the exact number of
// instructions generated, we insert padding here to keep the size
// of the Abort macro constant.
// Currently in debug mode with debug_code enabled the number of
// generated instructions is 14, so we use this as a maximum value.
static const int kExpectedAbortInstructions = 14;
int abort_instructions = InstructionsGeneratedSince(&abort_start);
ASSERT(abort_instructions <= kExpectedAbortInstructions);
while (abort_instructions++ < kExpectedAbortInstructions) {
nop();
}
}
}
void MacroAssembler::LoadContext(Register dst, int context_chain_length) {
if (context_chain_length > 0) {
// Move up the chain of contexts to the context containing the slot.
lw(dst, MemOperand(cp, Context::SlotOffset(Context::PREVIOUS_INDEX)));
for (int i = 1; i < context_chain_length; i++) {
lw(dst, MemOperand(dst, Context::SlotOffset(Context::PREVIOUS_INDEX)));
}
} else {
// Slot is in the current function context. Move it into the
// destination register in case we store into it (the write barrier
// cannot be allowed to destroy the context in esi).
Move(dst, cp);
}
}
void MacroAssembler::LoadGlobalFunction(int index, Register function) {
// Load the global or builtins object from the current context.
lw(function, MemOperand(cp, Context::SlotOffset(Context::GLOBAL_INDEX)));
// Load the global context from the global or builtins object.
lw(function, FieldMemOperand(function,
GlobalObject::kGlobalContextOffset));
// Load the function from the global context.
lw(function, MemOperand(function, Context::SlotOffset(index)));
}
void MacroAssembler::LoadGlobalFunctionInitialMap(Register function,
Register map,
Register scratch) {
// Load the initial map. The global functions all have initial maps.
lw(map, FieldMemOperand(function, JSFunction::kPrototypeOrInitialMapOffset));
if (emit_debug_code()) {
Label ok, fail;
CheckMap(map, scratch, Heap::kMetaMapRootIndex, &fail, DO_SMI_CHECK);
Branch(&ok);
bind(&fail);
Abort("Global functions must have initial map");
bind(&ok);
}
}
void MacroAssembler::EnterFrame(StackFrame::Type type) {
addiu(sp, sp, -5 * kPointerSize);
li(t8, Operand(Smi::FromInt(type)));
li(t9, Operand(CodeObject()));
sw(ra, MemOperand(sp, 4 * kPointerSize));
sw(fp, MemOperand(sp, 3 * kPointerSize));
sw(cp, MemOperand(sp, 2 * kPointerSize));
sw(t8, MemOperand(sp, 1 * kPointerSize));
sw(t9, MemOperand(sp, 0 * kPointerSize));
addiu(fp, sp, 3 * kPointerSize);
}
void MacroAssembler::LeaveFrame(StackFrame::Type type) {
mov(sp, fp);
lw(fp, MemOperand(sp, 0 * kPointerSize));
lw(ra, MemOperand(sp, 1 * kPointerSize));
addiu(sp, sp, 2 * kPointerSize);
}
void MacroAssembler::EnterExitFrame(bool save_doubles,
int stack_space) {
// Setup the frame structure on the stack.
STATIC_ASSERT(2 * kPointerSize == ExitFrameConstants::kCallerSPDisplacement);
STATIC_ASSERT(1 * kPointerSize == ExitFrameConstants::kCallerPCOffset);
STATIC_ASSERT(0 * kPointerSize == ExitFrameConstants::kCallerFPOffset);
// This is how the stack will look:
// fp + 2 (==kCallerSPDisplacement) - old stack's end
// [fp + 1 (==kCallerPCOffset)] - saved old ra
// [fp + 0 (==kCallerFPOffset)] - saved old fp
// [fp - 1 (==kSPOffset)] - sp of the called function
// [fp - 2 (==kCodeOffset)] - CodeObject
// fp - (2 + stack_space + alignment) == sp == [fp - kSPOffset] - top of the
// new stack (will contain saved ra)
// Save registers.
addiu(sp, sp, -4 * kPointerSize);
sw(ra, MemOperand(sp, 3 * kPointerSize));
sw(fp, MemOperand(sp, 2 * kPointerSize));
addiu(fp, sp, 2 * kPointerSize); // Setup new frame pointer.
if (emit_debug_code()) {
sw(zero_reg, MemOperand(fp, ExitFrameConstants::kSPOffset));
}
li(t8, Operand(CodeObject())); // Accessed from ExitFrame::code_slot.
sw(t8, MemOperand(fp, ExitFrameConstants::kCodeOffset));
// Save the frame pointer and the context in top.
li(t8, Operand(ExternalReference(Isolate::k_c_entry_fp_address, isolate())));
sw(fp, MemOperand(t8));
li(t8, Operand(ExternalReference(Isolate::k_context_address, isolate())));
sw(cp, MemOperand(t8));
const int frame_alignment = MacroAssembler::ActivationFrameAlignment();
if (save_doubles) {
// The stack must be allign to 0 modulo 8 for stores with sdc1.
ASSERT(kDoubleSize == frame_alignment);
if (frame_alignment > 0) {
ASSERT(IsPowerOf2(frame_alignment));
And(sp, sp, Operand(-frame_alignment)); // Align stack.
}
int space = FPURegister::kNumRegisters * kDoubleSize;
Subu(sp, sp, Operand(space));
// Remember: we only need to save every 2nd double FPU value.
for (int i = 0; i < FPURegister::kNumRegisters; i+=2) {
FPURegister reg = FPURegister::from_code(i);
sdc1(reg, MemOperand(sp, i * kDoubleSize));
}
}
// Reserve place for the return address, stack space and an optional slot
// (used by the DirectCEntryStub to hold the return value if a struct is
// returned) and align the frame preparing for calling the runtime function.
ASSERT(stack_space >= 0);
Subu(sp, sp, Operand((stack_space + 2) * kPointerSize));
if (frame_alignment > 0) {
ASSERT(IsPowerOf2(frame_alignment));
And(sp, sp, Operand(-frame_alignment)); // Align stack.
}
// Set the exit frame sp value to point just before the return address
// location.
addiu(at, sp, kPointerSize);
sw(at, MemOperand(fp, ExitFrameConstants::kSPOffset));
}
void MacroAssembler::LeaveExitFrame(bool save_doubles,
Register argument_count) {
// Optionally restore all double registers.
if (save_doubles) {
// Remember: we only need to restore every 2nd double FPU value.
lw(t8, MemOperand(fp, ExitFrameConstants::kSPOffset));
for (int i = 0; i < FPURegister::kNumRegisters; i+=2) {
FPURegister reg = FPURegister::from_code(i);
ldc1(reg, MemOperand(t8, i * kDoubleSize + kPointerSize));
}
}
// Clear top frame.
li(t8, Operand(ExternalReference(Isolate::k_c_entry_fp_address, isolate())));
sw(zero_reg, MemOperand(t8));
// Restore current context from top and clear it in debug mode.
li(t8, Operand(ExternalReference(Isolate::k_context_address, isolate())));
lw(cp, MemOperand(t8));
#ifdef DEBUG
sw(a3, MemOperand(t8));
#endif
// Pop the arguments, restore registers, and return.
mov(sp, fp); // Respect ABI stack constraint.
lw(fp, MemOperand(sp, ExitFrameConstants::kCallerFPOffset));
lw(ra, MemOperand(sp, ExitFrameConstants::kCallerPCOffset));
addiu(sp, sp, 8);
if (argument_count.is_valid()) {
sll(t8, argument_count, kPointerSizeLog2);
addu(sp, sp, t8);
}
}
void MacroAssembler::InitializeNewString(Register string,
Register length,
Heap::RootListIndex map_index,
Register scratch1,
Register scratch2) {
sll(scratch1, length, kSmiTagSize);
LoadRoot(scratch2, map_index);
sw(scratch1, FieldMemOperand(string, String::kLengthOffset));
li(scratch1, Operand(String::kEmptyHashField));
sw(scratch2, FieldMemOperand(string, HeapObject::kMapOffset));
sw(scratch1, FieldMemOperand(string, String::kHashFieldOffset));
}
int MacroAssembler::ActivationFrameAlignment() {
#if defined(V8_HOST_ARCH_MIPS)
// Running on the real platform. Use the alignment as mandated by the local
// environment.
// Note: This will break if we ever start generating snapshots on one Mips
// platform for another Mips platform with a different alignment.
return OS::ActivationFrameAlignment();
#else // defined(V8_HOST_ARCH_MIPS)
// If we are using the simulator then we should always align to the expected
// alignment. As the simulator is used to generate snapshots we do not know
// if the target platform will need alignment, so this is controlled from a
// flag.
return FLAG_sim_stack_alignment;
#endif // defined(V8_HOST_ARCH_MIPS)
}
void MacroAssembler::AssertStackIsAligned() {
if (emit_debug_code()) {
const int frame_alignment = ActivationFrameAlignment();
const int frame_alignment_mask = frame_alignment - 1;
if (frame_alignment > kPointerSize) {
Label alignment_as_expected;
ASSERT(IsPowerOf2(frame_alignment));
andi(at, sp, frame_alignment_mask);
Branch(&alignment_as_expected, eq, at, Operand(zero_reg));
// Don't use Check here, as it will call Runtime_Abort re-entering here.
stop("Unexpected stack alignment");
bind(&alignment_as_expected);
}
}
}
void MacroAssembler::JumpIfNotPowerOfTwoOrZero(
Register reg,
Register scratch,
Label* not_power_of_two_or_zero) {
Subu(scratch, reg, Operand(1));
Branch(USE_DELAY_SLOT, not_power_of_two_or_zero, lt,
scratch, Operand(zero_reg));
and_(at, scratch, reg); // In the delay slot.
Branch(not_power_of_two_or_zero, ne, at, Operand(zero_reg));
}
void MacroAssembler::JumpIfNotBothSmi(Register reg1,
Register reg2,
Label* on_not_both_smi) {
STATIC_ASSERT(kSmiTag == 0);
ASSERT_EQ(1, kSmiTagMask);
or_(at, reg1, reg2);
andi(at, at, kSmiTagMask);
Branch(on_not_both_smi, ne, at, Operand(zero_reg));
}
void MacroAssembler::JumpIfEitherSmi(Register reg1,
Register reg2,
Label* on_either_smi) {
STATIC_ASSERT(kSmiTag == 0);
ASSERT_EQ(1, kSmiTagMask);
// Both Smi tags must be 1 (not Smi).
and_(at, reg1, reg2);
andi(at, at, kSmiTagMask);
Branch(on_either_smi, eq, at, Operand(zero_reg));
}
void MacroAssembler::AbortIfSmi(Register object) {
STATIC_ASSERT(kSmiTag == 0);
andi(at, object, kSmiTagMask);
Assert(ne, "Operand is a smi", at, Operand(zero_reg));
}
void MacroAssembler::AbortIfNotSmi(Register object) {
STATIC_ASSERT(kSmiTag == 0);
andi(at, object, kSmiTagMask);
Assert(eq, "Operand is a smi", at, Operand(zero_reg));
}
void MacroAssembler::AbortIfNotString(Register object) {
STATIC_ASSERT(kSmiTag == 0);
And(t0, object, Operand(kSmiTagMask));
Assert(ne, "Operand is not a string", t0, Operand(zero_reg));
push(object);
lw(object, FieldMemOperand(object, HeapObject::kMapOffset));
lbu(object, FieldMemOperand(object, Map::kInstanceTypeOffset));
Assert(lo, "Operand is not a string", object, Operand(FIRST_NONSTRING_TYPE));
pop(object);
}
void MacroAssembler::AbortIfNotRootValue(Register src,
Heap::RootListIndex root_value_index,
const char* message) {
ASSERT(!src.is(at));
LoadRoot(at, root_value_index);
Assert(eq, message, src, Operand(at));
}
void MacroAssembler::JumpIfNotHeapNumber(Register object,
Register heap_number_map,
Register scratch,
Label* on_not_heap_number) {
lw(scratch, FieldMemOperand(object, HeapObject::kMapOffset));
AssertRegisterIsRoot(heap_number_map, Heap::kHeapNumberMapRootIndex);
Branch(on_not_heap_number, ne, scratch, Operand(heap_number_map));
}
void MacroAssembler::JumpIfNonSmisNotBothSequentialAsciiStrings(
Register first,
Register second,
Register scratch1,
Register scratch2,
Label* failure) {
// Test that both first and second are sequential ASCII strings.
// Assume that they are non-smis.
lw(scratch1, FieldMemOperand(first, HeapObject::kMapOffset));
lw(scratch2, FieldMemOperand(second, HeapObject::kMapOffset));
lbu(scratch1, FieldMemOperand(scratch1, Map::kInstanceTypeOffset));
lbu(scratch2, FieldMemOperand(scratch2, Map::kInstanceTypeOffset));
JumpIfBothInstanceTypesAreNotSequentialAscii(scratch1,
scratch2,
scratch1,
scratch2,
failure);
}
void MacroAssembler::JumpIfNotBothSequentialAsciiStrings(Register first,
Register second,
Register scratch1,
Register scratch2,
Label* failure) {
// Check that neither is a smi.
STATIC_ASSERT(kSmiTag == 0);
And(scratch1, first, Operand(second));
And(scratch1, scratch1, Operand(kSmiTagMask));
Branch(failure, eq, scratch1, Operand(zero_reg));
JumpIfNonSmisNotBothSequentialAsciiStrings(first,
second,
scratch1,
scratch2,
failure);
}
void MacroAssembler::JumpIfBothInstanceTypesAreNotSequentialAscii(
Register first,
Register second,
Register scratch1,
Register scratch2,
Label* failure) {
int kFlatAsciiStringMask =
kIsNotStringMask | kStringEncodingMask | kStringRepresentationMask;
int kFlatAsciiStringTag = ASCII_STRING_TYPE;
ASSERT(kFlatAsciiStringTag <= 0xffff); // Ensure this fits 16-bit immed.
andi(scratch1, first, kFlatAsciiStringMask);
Branch(failure, ne, scratch1, Operand(kFlatAsciiStringTag));
andi(scratch2, second, kFlatAsciiStringMask);
Branch(failure, ne, scratch2, Operand(kFlatAsciiStringTag));
}
void MacroAssembler::JumpIfInstanceTypeIsNotSequentialAscii(Register type,
Register scratch,
Label* failure) {
int kFlatAsciiStringMask =
kIsNotStringMask | kStringEncodingMask | kStringRepresentationMask;
int kFlatAsciiStringTag = ASCII_STRING_TYPE;
And(scratch, type, Operand(kFlatAsciiStringMask));
Branch(failure, ne, scratch, Operand(kFlatAsciiStringTag));
}
static const int kRegisterPassedArguments = 4;
void MacroAssembler::PrepareCallCFunction(int num_arguments, Register scratch) {
int frame_alignment = ActivationFrameAlignment();
// Up to four simple arguments are passed in registers a0..a3.
// Those four arguments must have reserved argument slots on the stack for
// mips, even though those argument slots are not normally used.
// Remaining arguments are pushed on the stack, above (higher address than)
// the argument slots.
ASSERT(StandardFrameConstants::kCArgsSlotsSize % kPointerSize == 0);
int stack_passed_arguments = ((num_arguments <= kRegisterPassedArguments) ?
0 : num_arguments - kRegisterPassedArguments) +
(StandardFrameConstants::kCArgsSlotsSize /
kPointerSize);
if (frame_alignment > kPointerSize) {
// Make stack end at alignment and make room for num_arguments - 4 words
// and the original value of sp.
mov(scratch, sp);
Subu(sp, sp, Operand((stack_passed_arguments + 1) * kPointerSize));
ASSERT(IsPowerOf2(frame_alignment));
And(sp, sp, Operand(-frame_alignment));
sw(scratch, MemOperand(sp, stack_passed_arguments * kPointerSize));
} else {
Subu(sp, sp, Operand(stack_passed_arguments * kPointerSize));
}
}
void MacroAssembler::CallCFunction(ExternalReference function,
int num_arguments) {
CallCFunctionHelper(no_reg, function, t8, num_arguments);
}
void MacroAssembler::CallCFunction(Register function,
Register scratch,
int num_arguments) {
CallCFunctionHelper(function,
ExternalReference::the_hole_value_location(isolate()),
scratch,
num_arguments);
}
void MacroAssembler::CallCFunctionHelper(Register function,
ExternalReference function_reference,
Register scratch,
int num_arguments) {
// Make sure that the stack is aligned before calling a C function unless
// running in the simulator. The simulator has its own alignment check which
// provides more information.
// The argument stots are presumed to have been set up by
// PrepareCallCFunction. The C function must be called via t9, for mips ABI.
#if defined(V8_HOST_ARCH_MIPS)
if (emit_debug_code()) {
int frame_alignment = OS::ActivationFrameAlignment();
int frame_alignment_mask = frame_alignment - 1;
if (frame_alignment > kPointerSize) {
ASSERT(IsPowerOf2(frame_alignment));
Label alignment_as_expected;
And(at, sp, Operand(frame_alignment_mask));
Branch(&alignment_as_expected, eq, at, Operand(zero_reg));
// Don't use Check here, as it will call Runtime_Abort possibly
// re-entering here.
stop("Unexpected alignment in CallCFunction");
bind(&alignment_as_expected);
}
}
#endif // V8_HOST_ARCH_MIPS
// Just call directly. The function called cannot cause a GC, or
// allow preemption, so the return address in the link register
// stays correct.
if (function.is(no_reg)) {
function = t9;
li(function, Operand(function_reference));
} else if (!function.is(t9)) {
mov(t9, function);
function = t9;
}
Call(function);
ASSERT(StandardFrameConstants::kCArgsSlotsSize % kPointerSize == 0);
int stack_passed_arguments = ((num_arguments <= kRegisterPassedArguments) ?
0 : num_arguments - kRegisterPassedArguments) +
(StandardFrameConstants::kCArgsSlotsSize /
kPointerSize);
if (OS::ActivationFrameAlignment() > kPointerSize) {
lw(sp, MemOperand(sp, stack_passed_arguments * kPointerSize));
} else {
Addu(sp, sp, Operand(stack_passed_arguments * sizeof(kPointerSize)));
}
}
#undef BRANCH_ARGS_CHECK
void MacroAssembler::LoadInstanceDescriptors(Register map,
Register descriptors) {
lw(descriptors,
FieldMemOperand(map, Map::kInstanceDescriptorsOrBitField3Offset));
Label not_smi;
JumpIfNotSmi(descriptors, &not_smi);
li(descriptors, Operand(FACTORY->empty_descriptor_array()));
bind(&not_smi);
}
CodePatcher::CodePatcher(byte* address, int instructions)
: address_(address),
instructions_(instructions),
size_(instructions * Assembler::kInstrSize),
masm_(Isolate::Current(), address, size_ + Assembler::kGap) {
// Create a new macro assembler pointing to the address of the code to patch.
// The size is adjusted with kGap on order for the assembler to generate size
// bytes of instructions without failing with buffer size constraints.
ASSERT(masm_.reloc_info_writer.pos() == address_ + size_ + Assembler::kGap);
}
CodePatcher::~CodePatcher() {
// Indicate that code has changed.
CPU::FlushICache(address_, size_);
// Check that the code was patched as expected.
ASSERT(masm_.pc_ == address_ + size_);
ASSERT(masm_.reloc_info_writer.pos() == address_ + size_ + Assembler::kGap);
}
void CodePatcher::Emit(Instr instr) {
masm()->emit(instr);
}
void CodePatcher::Emit(Address addr) {
masm()->emit(reinterpret_cast<Instr>(addr));
}
void CodePatcher::ChangeBranchCondition(Condition cond) {
Instr instr = Assembler::instr_at(masm_.pc_);
ASSERT(Assembler::IsBranch(instr));
uint32_t opcode = Assembler::GetOpcodeField(instr);
// Currently only the 'eq' and 'ne' cond values are supported and the simple
// branch instructions (with opcode being the branch type).
// There are some special cases (see Assembler::IsBranch()) so extending this
// would be tricky.
ASSERT(opcode == BEQ ||
opcode == BNE ||
opcode == BLEZ ||
opcode == BGTZ ||
opcode == BEQL ||
opcode == BNEL ||
opcode == BLEZL ||
opcode == BGTZL);
opcode = (cond == eq) ? BEQ : BNE;
instr = (instr & ~kOpcodeMask) | opcode;
masm_.emit(instr);
}
} } // namespace v8::internal
#endif // V8_TARGET_ARCH_MIPS