compiler/optimizing/code_generator_mips.h - platform/art - Gitiles

 /*
  * Copyright (C) 2015 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #ifndef ART_COMPILER_OPTIMIZING_CODE_GENERATOR_MIPS_H_
 #define ART_COMPILER_OPTIMIZING_CODE_GENERATOR_MIPS_H_

 #include "code_generator.h"
 #include "dex_file_types.h"
 #include "driver/compiler_options.h"
 #include "nodes.h"
 #include "parallel_move_resolver.h"
 #include "string_reference.h"
 #include "utils/mips/assembler_mips.h"
 #include "utils/type_reference.h"

 namespace art {
 namespace mips {

 // InvokeDexCallingConvention registers

 static constexpr Register kParameterCoreRegisters[] =
     { A1, A2, A3, T0, T1 };
 static constexpr size_t kParameterCoreRegistersLength = arraysize(kParameterCoreRegisters);

 static constexpr FRegister kParameterFpuRegisters[] =
     { F8, F10, F12, F14, F16, F18 };
 static constexpr size_t kParameterFpuRegistersLength = arraysize(kParameterFpuRegisters);


 // InvokeRuntimeCallingConvention registers

 static constexpr Register kRuntimeParameterCoreRegisters[] =
     { A0, A1, A2, A3 };
 static constexpr size_t kRuntimeParameterCoreRegistersLength =
     arraysize(kRuntimeParameterCoreRegisters);

 static constexpr FRegister kRuntimeParameterFpuRegisters[] =
     { F12, F14 };
 static constexpr size_t kRuntimeParameterFpuRegistersLength =
     arraysize(kRuntimeParameterFpuRegisters);


 static constexpr Register kCoreCalleeSaves[] =
     { S0, S1, S2, S3, S4, S5, S6, S7, FP, RA };
 static constexpr FRegister kFpuCalleeSaves[] =
     { F20, F22, F24, F26, F28, F30 };


 class CodeGeneratorMIPS;

 class InvokeDexCallingConvention : public CallingConvention<Register, FRegister> {
  public:
   InvokeDexCallingConvention()
       : CallingConvention(kParameterCoreRegisters,
                           kParameterCoreRegistersLength,
                           kParameterFpuRegisters,
                           kParameterFpuRegistersLength,
                           kMipsPointerSize) {}

  private:
   DISALLOW_COPY_AND_ASSIGN(InvokeDexCallingConvention);
 };

 class InvokeDexCallingConventionVisitorMIPS : public InvokeDexCallingConventionVisitor {
  public:
   InvokeDexCallingConventionVisitorMIPS() {}
   virtual ~InvokeDexCallingConventionVisitorMIPS() {}

   Location GetNextLocation(Primitive::Type type) OVERRIDE;
   Location GetReturnLocation(Primitive::Type type) const OVERRIDE;
   Location GetMethodLocation() const OVERRIDE;

  private:
   InvokeDexCallingConvention calling_convention;

   DISALLOW_COPY_AND_ASSIGN(InvokeDexCallingConventionVisitorMIPS);
 };

 class InvokeRuntimeCallingConvention : public CallingConvention<Register, FRegister> {
  public:
   InvokeRuntimeCallingConvention()
       : CallingConvention(kRuntimeParameterCoreRegisters,
                           kRuntimeParameterCoreRegistersLength,
                           kRuntimeParameterFpuRegisters,
                           kRuntimeParameterFpuRegistersLength,
                           kMipsPointerSize) {}

   Location GetReturnLocation(Primitive::Type return_type);

  private:
   DISALLOW_COPY_AND_ASSIGN(InvokeRuntimeCallingConvention);
 };

 class FieldAccessCallingConventionMIPS : public FieldAccessCallingConvention {
  public:
   FieldAccessCallingConventionMIPS() {}

   Location GetObjectLocation() const OVERRIDE {
     return Location::RegisterLocation(A1);
   }
   Location GetFieldIndexLocation() const OVERRIDE {
     return Location::RegisterLocation(A0);
   }
   Location GetReturnLocation(Primitive::Type type) const OVERRIDE {
     return Primitive::Is64BitType(type)
         ? Location::RegisterPairLocation(V0, V1)
         : Location::RegisterLocation(V0);
   }
   Location GetSetValueLocation(Primitive::Type type, bool is_instance) const OVERRIDE {
     return Primitive::Is64BitType(type)
         ? Location::RegisterPairLocation(A2, A3)
         : (is_instance ? Location::RegisterLocation(A2) : Location::RegisterLocation(A1));
   }
   Location GetFpuLocation(Primitive::Type type ATTRIBUTE_UNUSED) const OVERRIDE {
     return Location::FpuRegisterLocation(F0);
   }

  private:
   DISALLOW_COPY_AND_ASSIGN(FieldAccessCallingConventionMIPS);
 };

 class ParallelMoveResolverMIPS : public ParallelMoveResolverWithSwap {
  public:
   ParallelMoveResolverMIPS(ArenaAllocator* allocator, CodeGeneratorMIPS* codegen)
       : ParallelMoveResolverWithSwap(allocator), codegen_(codegen) {}

   void EmitMove(size_t index) OVERRIDE;
   void EmitSwap(size_t index) OVERRIDE;
   void SpillScratch(int reg) OVERRIDE;
   void RestoreScratch(int reg) OVERRIDE;

   void Exchange(int index1, int index2, bool double_slot);

   MipsAssembler* GetAssembler() const;

  private:
   CodeGeneratorMIPS* const codegen_;

   DISALLOW_COPY_AND_ASSIGN(ParallelMoveResolverMIPS);
 };

 class SlowPathCodeMIPS : public SlowPathCode {
  public:
   explicit SlowPathCodeMIPS(HInstruction* instruction)
       : SlowPathCode(instruction), entry_label_(), exit_label_() {}

   MipsLabel* GetEntryLabel() { return &entry_label_; }
   MipsLabel* GetExitLabel() { return &exit_label_; }

  private:
   MipsLabel entry_label_;
   MipsLabel exit_label_;

   DISALLOW_COPY_AND_ASSIGN(SlowPathCodeMIPS);
 };

 class LocationsBuilderMIPS : public HGraphVisitor {
  public:
   LocationsBuilderMIPS(HGraph* graph, CodeGeneratorMIPS* codegen)
       : HGraphVisitor(graph), codegen_(codegen) {}

 #define DECLARE_VISIT_INSTRUCTION(name, super)     \
   void Visit##name(H##name* instr) OVERRIDE;

   FOR_EACH_CONCRETE_INSTRUCTION_COMMON(DECLARE_VISIT_INSTRUCTION)
   FOR_EACH_CONCRETE_INSTRUCTION_MIPS(DECLARE_VISIT_INSTRUCTION)

 #undef DECLARE_VISIT_INSTRUCTION

   void VisitInstruction(HInstruction* instruction) OVERRIDE {
     LOG(FATAL) << "Unreachable instruction " << instruction->DebugName()
                << " (id " << instruction->GetId() << ")";
   }

  private:
   void HandleInvoke(HInvoke* invoke);
   void HandleBinaryOp(HBinaryOperation* operation);
   void HandleCondition(HCondition* instruction);
   void HandleShift(HBinaryOperation* operation);
   void HandleFieldSet(HInstruction* instruction, const FieldInfo& field_info);
   void HandleFieldGet(HInstruction* instruction, const FieldInfo& field_info);
   Location RegisterOrZeroConstant(HInstruction* instruction);
   Location FpuRegisterOrConstantForStore(HInstruction* instruction);

   InvokeDexCallingConventionVisitorMIPS parameter_visitor_;

   CodeGeneratorMIPS* const codegen_;

   DISALLOW_COPY_AND_ASSIGN(LocationsBuilderMIPS);
 };

 class InstructionCodeGeneratorMIPS : public InstructionCodeGenerator {
  public:
   InstructionCodeGeneratorMIPS(HGraph* graph, CodeGeneratorMIPS* codegen);

 #define DECLARE_VISIT_INSTRUCTION(name, super)     \
   void Visit##name(H##name* instr) OVERRIDE;

   FOR_EACH_CONCRETE_INSTRUCTION_COMMON(DECLARE_VISIT_INSTRUCTION)
   FOR_EACH_CONCRETE_INSTRUCTION_MIPS(DECLARE_VISIT_INSTRUCTION)

 #undef DECLARE_VISIT_INSTRUCTION

   void VisitInstruction(HInstruction* instruction) OVERRIDE {
     LOG(FATAL) << "Unreachable instruction " << instruction->DebugName()
                << " (id " << instruction->GetId() << ")";
   }

   MipsAssembler* GetAssembler() const { return assembler_; }

   // Compare-and-jump packed switch generates approx. 3 + 2.5 * N 32-bit
   // instructions for N cases.
   // Table-based packed switch generates approx. 11 32-bit instructions
   // and N 32-bit data words for N cases.
   // At N = 6 they come out as 18 and 17 32-bit words respectively.
   // We switch to the table-based method starting with 7 cases.
   static constexpr uint32_t kPackedSwitchJumpTableThreshold = 6;

  private:
   void GenerateClassInitializationCheck(SlowPathCodeMIPS* slow_path, Register class_reg);
   void GenerateMemoryBarrier(MemBarrierKind kind);
   void GenerateSuspendCheck(HSuspendCheck* check, HBasicBlock* successor);
   void HandleBinaryOp(HBinaryOperation* operation);
   void HandleCondition(HCondition* instruction);
   void HandleShift(HBinaryOperation* operation);
   void HandleFieldSet(HInstruction* instruction,
                       const FieldInfo& field_info,
                       uint32_t dex_pc,
                       bool value_can_be_null);
   void HandleFieldGet(HInstruction* instruction, const FieldInfo& field_info, uint32_t dex_pc);
   // Generate a GC root reference load:
   //
   //   root <- *(obj + offset)
   //
   // while honoring read barriers (if any).
   void GenerateGcRootFieldLoad(HInstruction* instruction,
                                Location root,
                                Register obj,
                                uint32_t offset);
   void GenerateIntCompare(IfCondition cond, LocationSummary* locations);
   // When the function returns `false` it means that the condition holds if `dst` is non-zero
   // and doesn't hold if `dst` is zero. If it returns `true`, the roles of zero and non-zero
   // `dst` are exchanged.
   bool MaterializeIntCompare(IfCondition cond,
                              LocationSummary* input_locations,
                              Register dst);
   void GenerateIntCompareAndBranch(IfCondition cond,
                                    LocationSummary* locations,
                                    MipsLabel* label);
   void GenerateLongCompareAndBranch(IfCondition cond,
                                     LocationSummary* locations,
                                     MipsLabel* label);
   void GenerateFpCompare(IfCondition cond,
                          bool gt_bias,
                          Primitive::Type type,
                          LocationSummary* locations);
   // When the function returns `false` it means that the condition holds if the condition
   // code flag `cc` is non-zero and doesn't hold if `cc` is zero. If it returns `true`,
   // the roles of zero and non-zero values of the `cc` flag are exchanged.
   bool MaterializeFpCompareR2(IfCondition cond,
                               bool gt_bias,
                               Primitive::Type type,
                               LocationSummary* input_locations,
                               int cc);
   // When the function returns `false` it means that the condition holds if `dst` is non-zero
   // and doesn't hold if `dst` is zero. If it returns `true`, the roles of zero and non-zero
   // `dst` are exchanged.
   bool MaterializeFpCompareR6(IfCondition cond,
                               bool gt_bias,
                               Primitive::Type type,
                               LocationSummary* input_locations,
                               FRegister dst);
   void GenerateFpCompareAndBranch(IfCondition cond,
                                   bool gt_bias,
                                   Primitive::Type type,
                                   LocationSummary* locations,
                                   MipsLabel* label);
   void GenerateTestAndBranch(HInstruction* instruction,
                              size_t condition_input_index,
                              MipsLabel* true_target,
                              MipsLabel* false_target);
   void DivRemOneOrMinusOne(HBinaryOperation* instruction);
   void DivRemByPowerOfTwo(HBinaryOperation* instruction);
   void GenerateDivRemWithAnyConstant(HBinaryOperation* instruction);
   void GenerateDivRemIntegral(HBinaryOperation* instruction);
   void HandleGoto(HInstruction* got, HBasicBlock* successor);
   void GenPackedSwitchWithCompares(Register value_reg,
                                    int32_t lower_bound,
                                    uint32_t num_entries,
                                    HBasicBlock* switch_block,
                                    HBasicBlock* default_block);
   void GenTableBasedPackedSwitch(Register value_reg,
                                  Register constant_area,
                                  int32_t lower_bound,
                                  uint32_t num_entries,
                                  HBasicBlock* switch_block,
                                  HBasicBlock* default_block);
   void GenConditionalMoveR2(HSelect* select);
   void GenConditionalMoveR6(HSelect* select);

   MipsAssembler* const assembler_;
   CodeGeneratorMIPS* const codegen_;

   DISALLOW_COPY_AND_ASSIGN(InstructionCodeGeneratorMIPS);
 };

 class CodeGeneratorMIPS : public CodeGenerator {
  public:
   CodeGeneratorMIPS(HGraph* graph,
                     const MipsInstructionSetFeatures& isa_features,
                     const CompilerOptions& compiler_options,
                     OptimizingCompilerStats* stats = nullptr);
   virtual ~CodeGeneratorMIPS() {}

   void ComputeSpillMask() OVERRIDE;
   bool HasAllocatedCalleeSaveRegisters() const OVERRIDE;
   void GenerateFrameEntry() OVERRIDE;
   void GenerateFrameExit() OVERRIDE;

   void Bind(HBasicBlock* block) OVERRIDE;

   void Move32(Location destination, Location source);
   void Move64(Location destination, Location source);
   void MoveConstant(Location location, HConstant* c);

   size_t GetWordSize() const OVERRIDE { return kMipsWordSize; }

   size_t GetFloatingPointSpillSlotSize() const OVERRIDE { return kMipsDoublewordSize; }

   uintptr_t GetAddressOf(HBasicBlock* block) OVERRIDE {
     return assembler_.GetLabelLocation(GetLabelOf(block));
   }

   HGraphVisitor* GetLocationBuilder() OVERRIDE { return &location_builder_; }
   HGraphVisitor* GetInstructionVisitor() OVERRIDE { return &instruction_visitor_; }
   MipsAssembler* GetAssembler() OVERRIDE { return &assembler_; }
   const MipsAssembler& GetAssembler() const OVERRIDE { return assembler_; }

   // Emit linker patches.
   void EmitLinkerPatches(ArenaVector<LinkerPatch>* linker_patches) OVERRIDE;
   void EmitJitRootPatches(uint8_t* code, const uint8_t* roots_data) OVERRIDE;

   void MarkGCCard(Register object, Register value, bool value_can_be_null);

   // Register allocation.

   void SetupBlockedRegisters() const OVERRIDE;

   size_t SaveCoreRegister(size_t stack_index, uint32_t reg_id) OVERRIDE;
   size_t RestoreCoreRegister(size_t stack_index, uint32_t reg_id) OVERRIDE;
   size_t SaveFloatingPointRegister(size_t stack_index, uint32_t reg_id) OVERRIDE;
   size_t RestoreFloatingPointRegister(size_t stack_index, uint32_t reg_id) OVERRIDE;
   void ClobberRA() {
     clobbered_ra_ = true;
   }

   void DumpCoreRegister(std::ostream& stream, int reg) const OVERRIDE;
   void DumpFloatingPointRegister(std::ostream& stream, int reg) const OVERRIDE;

   InstructionSet GetInstructionSet() const OVERRIDE { return InstructionSet::kMips; }

   const MipsInstructionSetFeatures& GetInstructionSetFeatures() const {
     return isa_features_;
   }

   MipsLabel* GetLabelOf(HBasicBlock* block) const {
     return CommonGetLabelOf<MipsLabel>(block_labels_, block);
   }

   void Initialize() OVERRIDE {
     block_labels_ = CommonInitializeLabels<MipsLabel>();
   }

   void Finalize(CodeAllocator* allocator) OVERRIDE;

   // Code generation helpers.

   void MoveLocation(Location dst, Location src, Primitive::Type dst_type) OVERRIDE;

   void MoveConstant(Location destination, int32_t value) OVERRIDE;

   void AddLocationAsTemp(Location location, LocationSummary* locations) OVERRIDE;

   // Generate code to invoke a runtime entry point.
   void InvokeRuntime(QuickEntrypointEnum entrypoint,
                      HInstruction* instruction,
                      uint32_t dex_pc,
                      SlowPathCode* slow_path = nullptr) OVERRIDE;

   ParallelMoveResolver* GetMoveResolver() OVERRIDE { return &move_resolver_; }

   bool NeedsTwoRegisters(Primitive::Type type) const OVERRIDE {
     return type == Primitive::kPrimLong;
   }

   // Check if the desired_string_load_kind is supported. If it is, return it,
   // otherwise return a fall-back kind that should be used instead.
   HLoadString::LoadKind GetSupportedLoadStringKind(
       HLoadString::LoadKind desired_string_load_kind) OVERRIDE;

   // Check if the desired_class_load_kind is supported. If it is, return it,
   // otherwise return a fall-back kind that should be used instead.
   HLoadClass::LoadKind GetSupportedLoadClassKind(
       HLoadClass::LoadKind desired_class_load_kind) OVERRIDE;

   // Check if the desired_dispatch_info is supported. If it is, return it,
   // otherwise return a fall-back info that should be used instead.
   HInvokeStaticOrDirect::DispatchInfo GetSupportedInvokeStaticOrDirectDispatch(
       const HInvokeStaticOrDirect::DispatchInfo& desired_dispatch_info,
       HInvokeStaticOrDirect* invoke) OVERRIDE;

   void GenerateStaticOrDirectCall(HInvokeStaticOrDirect* invoke, Location temp);
   void GenerateVirtualCall(HInvokeVirtual* invoke, Location temp) OVERRIDE;

   void MoveFromReturnRegister(Location trg ATTRIBUTE_UNUSED,
                               Primitive::Type type ATTRIBUTE_UNUSED) OVERRIDE {
     UNIMPLEMENTED(FATAL) << "Not implemented on MIPS";
   }

   void GenerateNop() OVERRIDE;
   void GenerateImplicitNullCheck(HNullCheck* instruction) OVERRIDE;
   void GenerateExplicitNullCheck(HNullCheck* instruction) OVERRIDE;

   // The PcRelativePatchInfo is used for PC-relative addressing of dex cache arrays
   // and boot image strings. The only difference is the interpretation of the offset_or_index.
   struct PcRelativePatchInfo {
     PcRelativePatchInfo(const DexFile& dex_file, uint32_t off_or_idx)
         : target_dex_file(dex_file), offset_or_index(off_or_idx) { }
     PcRelativePatchInfo(PcRelativePatchInfo&& other) = default;

     const DexFile& target_dex_file;
     // Either the dex cache array element offset or the string/type index.
     uint32_t offset_or_index;
     // Label for the instruction loading the most significant half of the offset that's added to PC
     // to form the base address (the least significant half is loaded with the instruction that
     // follows).
     MipsLabel high_label;
     // Label for the instruction corresponding to PC+0.
     MipsLabel pc_rel_label;
   };

   PcRelativePatchInfo* NewPcRelativeStringPatch(const DexFile& dex_file,
                                                 dex::StringIndex string_index);
   PcRelativePatchInfo* NewPcRelativeTypePatch(const DexFile& dex_file, dex::TypeIndex type_index);
   PcRelativePatchInfo* NewTypeBssEntryPatch(const DexFile& dex_file, dex::TypeIndex type_index);
   PcRelativePatchInfo* NewPcRelativeDexCacheArrayPatch(const DexFile& dex_file,
                                                        uint32_t element_offset);
   Literal* DeduplicateBootImageStringLiteral(const DexFile& dex_file,
                                              dex::StringIndex string_index);
   Literal* DeduplicateBootImageTypeLiteral(const DexFile& dex_file, dex::TypeIndex type_index);
   Literal* DeduplicateBootImageAddressLiteral(uint32_t address);

   void EmitPcRelativeAddressPlaceholderHigh(PcRelativePatchInfo* info, Register out, Register base);

   // The JitPatchInfo is used for JIT string and class loads.
   struct JitPatchInfo {
     JitPatchInfo(const DexFile& dex_file, uint64_t idx)
         : target_dex_file(dex_file), index(idx) { }
     JitPatchInfo(JitPatchInfo&& other) = default;

     const DexFile& target_dex_file;
     // String/type index.
     uint64_t index;
     // Label for the instruction loading the most significant half of the address.
     // The least significant half is loaded with the instruction that follows immediately.
     MipsLabel high_label;
   };

   void PatchJitRootUse(uint8_t* code,
                        const uint8_t* roots_data,
                        const JitPatchInfo& info,
                        uint64_t index_in_table) const;
   JitPatchInfo* NewJitRootStringPatch(const DexFile& dex_file,
                                       dex::StringIndex dex_index,
                                       Handle<mirror::String> handle);
   JitPatchInfo* NewJitRootClassPatch(const DexFile& dex_file,
                                      dex::TypeIndex dex_index,
                                      Handle<mirror::Class> handle);

  private:
   Register GetInvokeStaticOrDirectExtraParameter(HInvokeStaticOrDirect* invoke, Register temp);

   using Uint32ToLiteralMap = ArenaSafeMap<uint32_t, Literal*>;
   using MethodToLiteralMap = ArenaSafeMap<MethodReference, Literal*, MethodReferenceComparator>;
   using BootStringToLiteralMap = ArenaSafeMap<StringReference,
                                               Literal*,
                                               StringReferenceValueComparator>;
   using BootTypeToLiteralMap = ArenaSafeMap<TypeReference,
                                             Literal*,
                                             TypeReferenceValueComparator>;

   Literal* DeduplicateUint32Literal(uint32_t value, Uint32ToLiteralMap* map);
   Literal* DeduplicateMethodLiteral(MethodReference target_method, MethodToLiteralMap* map);
   PcRelativePatchInfo* NewPcRelativePatch(const DexFile& dex_file,
                                           uint32_t offset_or_index,
                                           ArenaDeque<PcRelativePatchInfo>* patches);

   template <LinkerPatch (*Factory)(size_t, const DexFile*, uint32_t, uint32_t)>
   void EmitPcRelativeLinkerPatches(const ArenaDeque<PcRelativePatchInfo>& infos,
                                    ArenaVector<LinkerPatch>* linker_patches);

   // Labels for each block that will be compiled.
   MipsLabel* block_labels_;
   MipsLabel frame_entry_label_;
   LocationsBuilderMIPS location_builder_;
   InstructionCodeGeneratorMIPS instruction_visitor_;
   ParallelMoveResolverMIPS move_resolver_;
   MipsAssembler assembler_;
   const MipsInstructionSetFeatures& isa_features_;

   // Deduplication map for 32-bit literals, used for non-patchable boot image addresses.
   Uint32ToLiteralMap uint32_literals_;
   // PC-relative patch info for each HMipsDexCacheArraysBase.
   ArenaDeque<PcRelativePatchInfo> pc_relative_dex_cache_patches_;
   // Deduplication map for boot string literals for kBootImageLinkTimeAddress.
   BootStringToLiteralMap boot_image_string_patches_;
   // PC-relative String patch info; type depends on configuration (app .bss or boot image PIC).
   ArenaDeque<PcRelativePatchInfo> pc_relative_string_patches_;
   // Deduplication map for boot type literals for kBootImageLinkTimeAddress.
   BootTypeToLiteralMap boot_image_type_patches_;
   // PC-relative type patch info for kBootImageLinkTimePcRelative.
   ArenaDeque<PcRelativePatchInfo> pc_relative_type_patches_;
   // PC-relative type patch info for kBssEntry.
   ArenaDeque<PcRelativePatchInfo> type_bss_entry_patches_;
   // Patches for string root accesses in JIT compiled code.
   ArenaDeque<JitPatchInfo> jit_string_patches_;
   // Patches for class root accesses in JIT compiled code.
   ArenaDeque<JitPatchInfo> jit_class_patches_;

   // PC-relative loads on R2 clobber RA, which may need to be preserved explicitly in leaf methods.
   // This is a flag set by pc_relative_fixups_mips and dex_cache_array_fixups_mips optimizations.
   bool clobbered_ra_;

   DISALLOW_COPY_AND_ASSIGN(CodeGeneratorMIPS);
 };

 }  // namespace mips
 }  // namespace art

 #endif  // ART_COMPILER_OPTIMIZING_CODE_GENERATOR_MIPS_H_
	/*
	* Copyright (C) 2015 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#ifndef ART_COMPILER_OPTIMIZING_CODE_GENERATOR_MIPS_H_
	#define ART_COMPILER_OPTIMIZING_CODE_GENERATOR_MIPS_H_

	#include "code_generator.h"
	#include "dex_file_types.h"
	#include "driver/compiler_options.h"
	#include "nodes.h"
	#include "parallel_move_resolver.h"
	#include "string_reference.h"
	#include "utils/mips/assembler_mips.h"
	#include "utils/type_reference.h"

	namespace art {
	namespace mips {

	// InvokeDexCallingConvention registers

	static constexpr Register kParameterCoreRegisters[] =
	{ A1, A2, A3, T0, T1 };
	static constexpr size_t kParameterCoreRegistersLength = arraysize(kParameterCoreRegisters);

	static constexpr FRegister kParameterFpuRegisters[] =
	{ F8, F10, F12, F14, F16, F18 };
	static constexpr size_t kParameterFpuRegistersLength = arraysize(kParameterFpuRegisters);


	// InvokeRuntimeCallingConvention registers

	static constexpr Register kRuntimeParameterCoreRegisters[] =
	{ A0, A1, A2, A3 };
	static constexpr size_t kRuntimeParameterCoreRegistersLength =
	arraysize(kRuntimeParameterCoreRegisters);

	static constexpr FRegister kRuntimeParameterFpuRegisters[] =
	{ F12, F14 };
	static constexpr size_t kRuntimeParameterFpuRegistersLength =
	arraysize(kRuntimeParameterFpuRegisters);


	static constexpr Register kCoreCalleeSaves[] =
	{ S0, S1, S2, S3, S4, S5, S6, S7, FP, RA };
	static constexpr FRegister kFpuCalleeSaves[] =
	{ F20, F22, F24, F26, F28, F30 };


	class CodeGeneratorMIPS;

	class InvokeDexCallingConvention : public CallingConvention<Register, FRegister> {
	public:
	InvokeDexCallingConvention()
	: CallingConvention(kParameterCoreRegisters,
	kParameterCoreRegistersLength,
	kParameterFpuRegisters,
	kParameterFpuRegistersLength,
	kMipsPointerSize) {}

	private:
	DISALLOW_COPY_AND_ASSIGN(InvokeDexCallingConvention);
	};

	class InvokeDexCallingConventionVisitorMIPS : public InvokeDexCallingConventionVisitor {
	public:
	InvokeDexCallingConventionVisitorMIPS() {}
	virtual ~InvokeDexCallingConventionVisitorMIPS() {}

	Location GetNextLocation(Primitive::Type type) OVERRIDE;
	Location GetReturnLocation(Primitive::Type type) const OVERRIDE;
	Location GetMethodLocation() const OVERRIDE;

	private:
	InvokeDexCallingConvention calling_convention;

	DISALLOW_COPY_AND_ASSIGN(InvokeDexCallingConventionVisitorMIPS);
	};

	class InvokeRuntimeCallingConvention : public CallingConvention<Register, FRegister> {
	public:
	InvokeRuntimeCallingConvention()
	: CallingConvention(kRuntimeParameterCoreRegisters,
	kRuntimeParameterCoreRegistersLength,
	kRuntimeParameterFpuRegisters,
	kRuntimeParameterFpuRegistersLength,
	kMipsPointerSize) {}

	Location GetReturnLocation(Primitive::Type return_type);

	private:
	DISALLOW_COPY_AND_ASSIGN(InvokeRuntimeCallingConvention);
	};

	class FieldAccessCallingConventionMIPS : public FieldAccessCallingConvention {
	public:
	FieldAccessCallingConventionMIPS() {}

	Location GetObjectLocation() const OVERRIDE {
	return Location::RegisterLocation(A1);
	}
	Location GetFieldIndexLocation() const OVERRIDE {
	return Location::RegisterLocation(A0);
	}
	Location GetReturnLocation(Primitive::Type type) const OVERRIDE {
	return Primitive::Is64BitType(type)
	? Location::RegisterPairLocation(V0, V1)
	: Location::RegisterLocation(V0);
	}
	Location GetSetValueLocation(Primitive::Type type, bool is_instance) const OVERRIDE {
	return Primitive::Is64BitType(type)
	? Location::RegisterPairLocation(A2, A3)
	: (is_instance ? Location::RegisterLocation(A2) : Location::RegisterLocation(A1));
	}
	Location GetFpuLocation(Primitive::Type type ATTRIBUTE_UNUSED) const OVERRIDE {
	return Location::FpuRegisterLocation(F0);
	}

	private:
	DISALLOW_COPY_AND_ASSIGN(FieldAccessCallingConventionMIPS);
	};

	class ParallelMoveResolverMIPS : public ParallelMoveResolverWithSwap {
	public:
	ParallelMoveResolverMIPS(ArenaAllocator* allocator, CodeGeneratorMIPS* codegen)
	: ParallelMoveResolverWithSwap(allocator), codegen_(codegen) {}

	void EmitMove(size_t index) OVERRIDE;
	void EmitSwap(size_t index) OVERRIDE;
	void SpillScratch(int reg) OVERRIDE;
	void RestoreScratch(int reg) OVERRIDE;

	void Exchange(int index1, int index2, bool double_slot);

	MipsAssembler* GetAssembler() const;

	private:
	CodeGeneratorMIPS* const codegen_;

	DISALLOW_COPY_AND_ASSIGN(ParallelMoveResolverMIPS);
	};

	class SlowPathCodeMIPS : public SlowPathCode {
	public:
	explicit SlowPathCodeMIPS(HInstruction* instruction)
	: SlowPathCode(instruction), entry_label_(), exit_label_() {}

	MipsLabel* GetEntryLabel() { return &entry_label_; }
	MipsLabel* GetExitLabel() { return &exit_label_; }

	private:
	MipsLabel entry_label_;
	MipsLabel exit_label_;

	DISALLOW_COPY_AND_ASSIGN(SlowPathCodeMIPS);
	};

	class LocationsBuilderMIPS : public HGraphVisitor {
	public:
	LocationsBuilderMIPS(HGraph* graph, CodeGeneratorMIPS* codegen)
	: HGraphVisitor(graph), codegen_(codegen) {}

	#define DECLARE_VISIT_INSTRUCTION(name, super) \
	void Visit##name(H##name* instr) OVERRIDE;

	FOR_EACH_CONCRETE_INSTRUCTION_COMMON(DECLARE_VISIT_INSTRUCTION)
	FOR_EACH_CONCRETE_INSTRUCTION_MIPS(DECLARE_VISIT_INSTRUCTION)

	#undef DECLARE_VISIT_INSTRUCTION

	void VisitInstruction(HInstruction* instruction) OVERRIDE {
	LOG(FATAL) << "Unreachable instruction " << instruction->DebugName()
	<< " (id " << instruction->GetId() << ")";
	}

	private:
	void HandleInvoke(HInvoke* invoke);
	void HandleBinaryOp(HBinaryOperation* operation);
	void HandleCondition(HCondition* instruction);
	void HandleShift(HBinaryOperation* operation);
	void HandleFieldSet(HInstruction* instruction, const FieldInfo& field_info);
	void HandleFieldGet(HInstruction* instruction, const FieldInfo& field_info);
	Location RegisterOrZeroConstant(HInstruction* instruction);
	Location FpuRegisterOrConstantForStore(HInstruction* instruction);

	InvokeDexCallingConventionVisitorMIPS parameter_visitor_;

	CodeGeneratorMIPS* const codegen_;

	DISALLOW_COPY_AND_ASSIGN(LocationsBuilderMIPS);
	};

	class InstructionCodeGeneratorMIPS : public InstructionCodeGenerator {
	public:
	InstructionCodeGeneratorMIPS(HGraph* graph, CodeGeneratorMIPS* codegen);

	#define DECLARE_VISIT_INSTRUCTION(name, super) \
	void Visit##name(H##name* instr) OVERRIDE;

	FOR_EACH_CONCRETE_INSTRUCTION_COMMON(DECLARE_VISIT_INSTRUCTION)
	FOR_EACH_CONCRETE_INSTRUCTION_MIPS(DECLARE_VISIT_INSTRUCTION)

	#undef DECLARE_VISIT_INSTRUCTION

	void VisitInstruction(HInstruction* instruction) OVERRIDE {
	LOG(FATAL) << "Unreachable instruction " << instruction->DebugName()
	<< " (id " << instruction->GetId() << ")";
	}

	MipsAssembler* GetAssembler() const { return assembler_; }

	// Compare-and-jump packed switch generates approx. 3 + 2.5 * N 32-bit
	// instructions for N cases.
	// Table-based packed switch generates approx. 11 32-bit instructions
	// and N 32-bit data words for N cases.
	// At N = 6 they come out as 18 and 17 32-bit words respectively.
	// We switch to the table-based method starting with 7 cases.
	static constexpr uint32_t kPackedSwitchJumpTableThreshold = 6;

	private:
	void GenerateClassInitializationCheck(SlowPathCodeMIPS* slow_path, Register class_reg);
	void GenerateMemoryBarrier(MemBarrierKind kind);
	void GenerateSuspendCheck(HSuspendCheck* check, HBasicBlock* successor);
	void HandleBinaryOp(HBinaryOperation* operation);
	void HandleCondition(HCondition* instruction);
	void HandleShift(HBinaryOperation* operation);
	void HandleFieldSet(HInstruction* instruction,
	const FieldInfo& field_info,
	uint32_t dex_pc,
	bool value_can_be_null);
	void HandleFieldGet(HInstruction* instruction, const FieldInfo& field_info, uint32_t dex_pc);
	// Generate a GC root reference load:
	//
	// root <- *(obj + offset)
	//
	// while honoring read barriers (if any).
	void GenerateGcRootFieldLoad(HInstruction* instruction,
	Location root,
	Register obj,
	uint32_t offset);
	void GenerateIntCompare(IfCondition cond, LocationSummary* locations);
	// When the function returns `false` it means that the condition holds if `dst` is non-zero
	// and doesn't hold if `dst` is zero. If it returns `true`, the roles of zero and non-zero
	// `dst` are exchanged.
	bool MaterializeIntCompare(IfCondition cond,
	LocationSummary* input_locations,
	Register dst);
	void GenerateIntCompareAndBranch(IfCondition cond,
	LocationSummary* locations,
	MipsLabel* label);
	void GenerateLongCompareAndBranch(IfCondition cond,
	LocationSummary* locations,
	MipsLabel* label);
	void GenerateFpCompare(IfCondition cond,
	bool gt_bias,
	Primitive::Type type,
	LocationSummary* locations);
	// When the function returns `false` it means that the condition holds if the condition
	// code flag `cc` is non-zero and doesn't hold if `cc` is zero. If it returns `true`,
	// the roles of zero and non-zero values of the `cc` flag are exchanged.
	bool MaterializeFpCompareR2(IfCondition cond,
	bool gt_bias,
	Primitive::Type type,
	LocationSummary* input_locations,
	int cc);
	// When the function returns `false` it means that the condition holds if `dst` is non-zero
	// and doesn't hold if `dst` is zero. If it returns `true`, the roles of zero and non-zero
	// `dst` are exchanged.
	bool MaterializeFpCompareR6(IfCondition cond,
	bool gt_bias,
	Primitive::Type type,
	LocationSummary* input_locations,
	FRegister dst);
	void GenerateFpCompareAndBranch(IfCondition cond,
	bool gt_bias,
	Primitive::Type type,
	LocationSummary* locations,
	MipsLabel* label);
	void GenerateTestAndBranch(HInstruction* instruction,
	size_t condition_input_index,
	MipsLabel* true_target,
	MipsLabel* false_target);
	void DivRemOneOrMinusOne(HBinaryOperation* instruction);
	void DivRemByPowerOfTwo(HBinaryOperation* instruction);
	void GenerateDivRemWithAnyConstant(HBinaryOperation* instruction);
	void GenerateDivRemIntegral(HBinaryOperation* instruction);
	void HandleGoto(HInstruction* got, HBasicBlock* successor);
	void GenPackedSwitchWithCompares(Register value_reg,
	int32_t lower_bound,
	uint32_t num_entries,
	HBasicBlock* switch_block,
	HBasicBlock* default_block);
	void GenTableBasedPackedSwitch(Register value_reg,
	Register constant_area,
	int32_t lower_bound,
	uint32_t num_entries,
	HBasicBlock* switch_block,
	HBasicBlock* default_block);
	void GenConditionalMoveR2(HSelect* select);
	void GenConditionalMoveR6(HSelect* select);

	MipsAssembler* const assembler_;
	CodeGeneratorMIPS* const codegen_;

	DISALLOW_COPY_AND_ASSIGN(InstructionCodeGeneratorMIPS);
	};

	class CodeGeneratorMIPS : public CodeGenerator {
	public:
	CodeGeneratorMIPS(HGraph* graph,
	const MipsInstructionSetFeatures& isa_features,
	const CompilerOptions& compiler_options,
	OptimizingCompilerStats* stats = nullptr);
	virtual ~CodeGeneratorMIPS() {}

	void ComputeSpillMask() OVERRIDE;
	bool HasAllocatedCalleeSaveRegisters() const OVERRIDE;
	void GenerateFrameEntry() OVERRIDE;
	void GenerateFrameExit() OVERRIDE;

	void Bind(HBasicBlock* block) OVERRIDE;

	void Move32(Location destination, Location source);
	void Move64(Location destination, Location source);
	void MoveConstant(Location location, HConstant* c);

	size_t GetWordSize() const OVERRIDE { return kMipsWordSize; }

	size_t GetFloatingPointSpillSlotSize() const OVERRIDE { return kMipsDoublewordSize; }

	uintptr_t GetAddressOf(HBasicBlock* block) OVERRIDE {
	return assembler_.GetLabelLocation(GetLabelOf(block));
	}

	HGraphVisitor* GetLocationBuilder() OVERRIDE { return &location_builder_; }
	HGraphVisitor* GetInstructionVisitor() OVERRIDE { return &instruction_visitor_; }
	MipsAssembler* GetAssembler() OVERRIDE { return &assembler_; }
	const MipsAssembler& GetAssembler() const OVERRIDE { return assembler_; }

	// Emit linker patches.
	void EmitLinkerPatches(ArenaVector<LinkerPatch>* linker_patches) OVERRIDE;
	void EmitJitRootPatches(uint8_t* code, const uint8_t* roots_data) OVERRIDE;

	void MarkGCCard(Register object, Register value, bool value_can_be_null);

	// Register allocation.

	void SetupBlockedRegisters() const OVERRIDE;

	size_t SaveCoreRegister(size_t stack_index, uint32_t reg_id) OVERRIDE;
	size_t RestoreCoreRegister(size_t stack_index, uint32_t reg_id) OVERRIDE;
	size_t SaveFloatingPointRegister(size_t stack_index, uint32_t reg_id) OVERRIDE;
	size_t RestoreFloatingPointRegister(size_t stack_index, uint32_t reg_id) OVERRIDE;
	void ClobberRA() {
	clobbered_ra_ = true;
	}

	void DumpCoreRegister(std::ostream& stream, int reg) const OVERRIDE;
	void DumpFloatingPointRegister(std::ostream& stream, int reg) const OVERRIDE;

	InstructionSet GetInstructionSet() const OVERRIDE { return InstructionSet::kMips; }

	const MipsInstructionSetFeatures& GetInstructionSetFeatures() const {
	return isa_features_;
	}

	MipsLabel* GetLabelOf(HBasicBlock* block) const {
	return CommonGetLabelOf<MipsLabel>(block_labels_, block);
	}

	void Initialize() OVERRIDE {
	block_labels_ = CommonInitializeLabels<MipsLabel>();
	}

	void Finalize(CodeAllocator* allocator) OVERRIDE;

	// Code generation helpers.

	void MoveLocation(Location dst, Location src, Primitive::Type dst_type) OVERRIDE;

	void MoveConstant(Location destination, int32_t value) OVERRIDE;

	void AddLocationAsTemp(Location location, LocationSummary* locations) OVERRIDE;

	// Generate code to invoke a runtime entry point.
	void InvokeRuntime(QuickEntrypointEnum entrypoint,
	HInstruction* instruction,
	uint32_t dex_pc,
	SlowPathCode* slow_path = nullptr) OVERRIDE;

	ParallelMoveResolver* GetMoveResolver() OVERRIDE { return &move_resolver_; }

	bool NeedsTwoRegisters(Primitive::Type type) const OVERRIDE {
	return type == Primitive::kPrimLong;
	}

	// Check if the desired_string_load_kind is supported. If it is, return it,
	// otherwise return a fall-back kind that should be used instead.
	HLoadString::LoadKind GetSupportedLoadStringKind(
	HLoadString::LoadKind desired_string_load_kind) OVERRIDE;

	// Check if the desired_class_load_kind is supported. If it is, return it,
	// otherwise return a fall-back kind that should be used instead.
	HLoadClass::LoadKind GetSupportedLoadClassKind(
	HLoadClass::LoadKind desired_class_load_kind) OVERRIDE;

	// Check if the desired_dispatch_info is supported. If it is, return it,
	// otherwise return a fall-back info that should be used instead.
	HInvokeStaticOrDirect::DispatchInfo GetSupportedInvokeStaticOrDirectDispatch(
	const HInvokeStaticOrDirect::DispatchInfo& desired_dispatch_info,
	HInvokeStaticOrDirect* invoke) OVERRIDE;

	void GenerateStaticOrDirectCall(HInvokeStaticOrDirect* invoke, Location temp);
	void GenerateVirtualCall(HInvokeVirtual* invoke, Location temp) OVERRIDE;

	void MoveFromReturnRegister(Location trg ATTRIBUTE_UNUSED,
	Primitive::Type type ATTRIBUTE_UNUSED) OVERRIDE {
	UNIMPLEMENTED(FATAL) << "Not implemented on MIPS";
	}

	void GenerateNop() OVERRIDE;
	void GenerateImplicitNullCheck(HNullCheck* instruction) OVERRIDE;
	void GenerateExplicitNullCheck(HNullCheck* instruction) OVERRIDE;

	// The PcRelativePatchInfo is used for PC-relative addressing of dex cache arrays
	// and boot image strings. The only difference is the interpretation of the offset_or_index.
	struct PcRelativePatchInfo {
	PcRelativePatchInfo(const DexFile& dex_file, uint32_t off_or_idx)
	: target_dex_file(dex_file), offset_or_index(off_or_idx) { }
	PcRelativePatchInfo(PcRelativePatchInfo&& other) = default;

	const DexFile& target_dex_file;
	// Either the dex cache array element offset or the string/type index.
	uint32_t offset_or_index;
	// Label for the instruction loading the most significant half of the offset that's added to PC
	// to form the base address (the least significant half is loaded with the instruction that
	// follows).
	MipsLabel high_label;
	// Label for the instruction corresponding to PC+0.
	MipsLabel pc_rel_label;
	};

	PcRelativePatchInfo* NewPcRelativeStringPatch(const DexFile& dex_file,
	dex::StringIndex string_index);
	PcRelativePatchInfo* NewPcRelativeTypePatch(const DexFile& dex_file, dex::TypeIndex type_index);
	PcRelativePatchInfo* NewTypeBssEntryPatch(const DexFile& dex_file, dex::TypeIndex type_index);
	PcRelativePatchInfo* NewPcRelativeDexCacheArrayPatch(const DexFile& dex_file,
	uint32_t element_offset);
	Literal* DeduplicateBootImageStringLiteral(const DexFile& dex_file,
	dex::StringIndex string_index);
	Literal* DeduplicateBootImageTypeLiteral(const DexFile& dex_file, dex::TypeIndex type_index);
	Literal* DeduplicateBootImageAddressLiteral(uint32_t address);

	void EmitPcRelativeAddressPlaceholderHigh(PcRelativePatchInfo* info, Register out, Register base);

	// The JitPatchInfo is used for JIT string and class loads.
	struct JitPatchInfo {
	JitPatchInfo(const DexFile& dex_file, uint64_t idx)
	: target_dex_file(dex_file), index(idx) { }
	JitPatchInfo(JitPatchInfo&& other) = default;

	const DexFile& target_dex_file;
	// String/type index.
	uint64_t index;
	// Label for the instruction loading the most significant half of the address.
	// The least significant half is loaded with the instruction that follows immediately.
	MipsLabel high_label;
	};

	void PatchJitRootUse(uint8_t* code,
	const uint8_t* roots_data,
	const JitPatchInfo& info,
	uint64_t index_in_table) const;
	JitPatchInfo* NewJitRootStringPatch(const DexFile& dex_file,
	dex::StringIndex dex_index,
	Handle<mirror::String> handle);
	JitPatchInfo* NewJitRootClassPatch(const DexFile& dex_file,
	dex::TypeIndex dex_index,
	Handle<mirror::Class> handle);

	private:
	Register GetInvokeStaticOrDirectExtraParameter(HInvokeStaticOrDirect* invoke, Register temp);

	using Uint32ToLiteralMap = ArenaSafeMap<uint32_t, Literal*>;
	using MethodToLiteralMap = ArenaSafeMap<MethodReference, Literal*, MethodReferenceComparator>;
	using BootStringToLiteralMap = ArenaSafeMap<StringReference,
	Literal*,
	StringReferenceValueComparator>;
	using BootTypeToLiteralMap = ArenaSafeMap<TypeReference,
	Literal*,
	TypeReferenceValueComparator>;

	Literal* DeduplicateUint32Literal(uint32_t value, Uint32ToLiteralMap* map);
	Literal* DeduplicateMethodLiteral(MethodReference target_method, MethodToLiteralMap* map);
	PcRelativePatchInfo* NewPcRelativePatch(const DexFile& dex_file,
	uint32_t offset_or_index,
	ArenaDeque<PcRelativePatchInfo>* patches);

	template <LinkerPatch (Factory)(size_t, const DexFile, uint32_t, uint32_t)>
	void EmitPcRelativeLinkerPatches(const ArenaDeque<PcRelativePatchInfo>& infos,
	ArenaVector<LinkerPatch>* linker_patches);

	// Labels for each block that will be compiled.
	MipsLabel* block_labels_;
	MipsLabel frame_entry_label_;
	LocationsBuilderMIPS location_builder_;
	InstructionCodeGeneratorMIPS instruction_visitor_;
	ParallelMoveResolverMIPS move_resolver_;
	MipsAssembler assembler_;
	const MipsInstructionSetFeatures& isa_features_;

	// Deduplication map for 32-bit literals, used for non-patchable boot image addresses.
	Uint32ToLiteralMap uint32_literals_;
	// PC-relative patch info for each HMipsDexCacheArraysBase.
	ArenaDeque<PcRelativePatchInfo> pc_relative_dex_cache_patches_;
	// Deduplication map for boot string literals for kBootImageLinkTimeAddress.
	BootStringToLiteralMap boot_image_string_patches_;
	// PC-relative String patch info; type depends on configuration (app .bss or boot image PIC).
	ArenaDeque<PcRelativePatchInfo> pc_relative_string_patches_;
	// Deduplication map for boot type literals for kBootImageLinkTimeAddress.
	BootTypeToLiteralMap boot_image_type_patches_;
	// PC-relative type patch info for kBootImageLinkTimePcRelative.
	ArenaDeque<PcRelativePatchInfo> pc_relative_type_patches_;
	// PC-relative type patch info for kBssEntry.
	ArenaDeque<PcRelativePatchInfo> type_bss_entry_patches_;
	// Patches for string root accesses in JIT compiled code.
	ArenaDeque<JitPatchInfo> jit_string_patches_;
	// Patches for class root accesses in JIT compiled code.
	ArenaDeque<JitPatchInfo> jit_class_patches_;

	// PC-relative loads on R2 clobber RA, which may need to be preserved explicitly in leaf methods.
	// This is a flag set by pc_relative_fixups_mips and dex_cache_array_fixups_mips optimizations.
	bool clobbered_ra_;

	DISALLOW_COPY_AND_ASSIGN(CodeGeneratorMIPS);
	};

	} // namespace mips
	} // namespace art

	#endif // ART_COMPILER_OPTIMIZING_CODE_GENERATOR_MIPS_H_