src/v8/src/arm64/code-stubs-arm64.h - cobalt - Git at Google

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 #ifndef V8_ARM64_CODE_STUBS_ARM64_H_
 #define V8_ARM64_CODE_STUBS_ARM64_H_

 namespace v8 {
 namespace internal {


 class StringHelper : public AllStatic {
  public:
   // Compares two flat one-byte strings and returns result in x0.
   static void GenerateCompareFlatOneByteStrings(
       MacroAssembler* masm, Register left, Register right, Register scratch1,
       Register scratch2, Register scratch3, Register scratch4);

   // Compare two flat one-byte strings for equality and returns result in x0.
   static void GenerateFlatOneByteStringEquals(MacroAssembler* masm,
                                               Register left, Register right,
                                               Register scratch1,
                                               Register scratch2,
                                               Register scratch3);

  private:
   static void GenerateOneByteCharsCompareLoop(
       MacroAssembler* masm, Register left, Register right, Register length,
       Register scratch1, Register scratch2, Label* chars_not_equal);

   DISALLOW_IMPLICIT_CONSTRUCTORS(StringHelper);
 };


 class RecordWriteStub: public PlatformCodeStub {
  public:
   // Stub to record the write of 'value' at 'address' in 'object'.
   // Typically 'address' = 'object' + <some offset>.
   // See MacroAssembler::RecordWriteField() for example.
   RecordWriteStub(Isolate* isolate,
                   Register object,
                   Register value,
                   Register address,
                   RememberedSetAction remembered_set_action,
                   SaveFPRegsMode fp_mode)
       : PlatformCodeStub(isolate),
         regs_(object,   // An input reg.
               address,  // An input reg.
               value) {  // One scratch reg.
     DCHECK(object.Is64Bits());
     DCHECK(value.Is64Bits());
     DCHECK(address.Is64Bits());
     minor_key_ = ObjectBits::encode(object.code()) |
                  ValueBits::encode(value.code()) |
                  AddressBits::encode(address.code()) |
                  RememberedSetActionBits::encode(remembered_set_action) |
                  SaveFPRegsModeBits::encode(fp_mode);
   }

   RecordWriteStub(uint32_t key, Isolate* isolate)
       : PlatformCodeStub(key, isolate), regs_(object(), address(), value()) {}

   enum Mode {
     STORE_BUFFER_ONLY,
     INCREMENTAL,
     INCREMENTAL_COMPACTION
   };

   bool SometimesSetsUpAFrame() override { return false; }

   static Mode GetMode(Code* stub);

   static void Patch(Code* stub, Mode mode);

   DEFINE_NULL_CALL_INTERFACE_DESCRIPTOR();

  private:
   // This is a helper class to manage the registers associated with the stub.
   // The 'object' and 'address' registers must be preserved.
   class RegisterAllocation {
    public:
     RegisterAllocation(Register object, Register address, Register scratch);

     void Save(MacroAssembler* masm) {
       // We don't have to save scratch0_ because it was given to us as
       // a scratch register.
       masm->Push(scratch1_, scratch2_);
     }

     void Restore(MacroAssembler* masm) {
       masm->Pop(scratch2_, scratch1_);
     }

     // If we have to call into C then we need to save and restore all caller-
     // saved registers that were not already preserved.
     void SaveCallerSaveRegisters(MacroAssembler* masm, SaveFPRegsMode mode) {
       // TODO(all): This can be very expensive, and it is likely that not every
       // register will need to be preserved. Can we improve this?
       masm->PushCPURegList(saved_regs_);
       if (mode == kSaveFPRegs) {
         masm->PushCPURegList(saved_fp_regs_);
       }
     }

     void RestoreCallerSaveRegisters(MacroAssembler*masm, SaveFPRegsMode mode) {
       // TODO(all): This can be very expensive, and it is likely that not every
       // register will need to be preserved. Can we improve this?
       if (mode == kSaveFPRegs) {
         masm->PopCPURegList(saved_fp_regs_);
       }
       masm->PopCPURegList(saved_regs_);
     }

     Register object() { return object_; }
     Register address() { return address_; }
     Register scratch0() { return scratch0_; }
     Register scratch1() { return scratch1_; }
     Register scratch2() { return scratch2_; }

    private:
     Register object_;
     Register address_;
     Register scratch0_;
     Register scratch1_ = NoReg;
     Register scratch2_ = NoReg;
     CPURegList saved_regs_;
     CPURegList saved_fp_regs_;

     // TODO(all): We should consider moving this somewhere else.
     static CPURegList GetValidRegistersForAllocation() {
       // The list of valid registers for allocation is defined as all the
       // registers without those with a special meaning.
       //
       // The default list excludes registers x26 to x31 because they are
       // reserved for the following purpose:
       //  - x26 root register
       //  - x27 context pointer register
       //  - x28 jssp
       //  - x29 frame pointer
       //  - x30 link register(lr)
       //  - x31 xzr/stack pointer
       CPURegList list(CPURegister::kRegister, kXRegSizeInBits, 0, 25);

       // We also remove MacroAssembler's scratch registers.
       list.Remove(MacroAssembler::DefaultTmpList());

       return list;
     }

     friend class RecordWriteStub;
   };

   enum OnNoNeedToInformIncrementalMarker {
     kReturnOnNoNeedToInformIncrementalMarker,
     kUpdateRememberedSetOnNoNeedToInformIncrementalMarker
   };

   inline Major MajorKey() const final { return RecordWrite; }

   void Generate(MacroAssembler* masm) override;
   void GenerateIncremental(MacroAssembler* masm, Mode mode);
   void CheckNeedsToInformIncrementalMarker(
       MacroAssembler* masm,
       OnNoNeedToInformIncrementalMarker on_no_need,
       Mode mode);
   void InformIncrementalMarker(MacroAssembler* masm);

   void Activate(Code* code) override;

   Register object() const {
     return Register::from_code(ObjectBits::decode(minor_key_));
   }

   Register value() const {
     return Register::from_code(ValueBits::decode(minor_key_));
   }

   Register address() const {
     return Register::from_code(AddressBits::decode(minor_key_));
   }

   RememberedSetAction remembered_set_action() const {
     return RememberedSetActionBits::decode(minor_key_);
   }

   SaveFPRegsMode save_fp_regs_mode() const {
     return SaveFPRegsModeBits::decode(minor_key_);
   }

   class ObjectBits: public BitField<int, 0, 5> {};
   class ValueBits: public BitField<int, 5, 5> {};
   class AddressBits: public BitField<int, 10, 5> {};
   class RememberedSetActionBits: public BitField<RememberedSetAction, 15, 1> {};
   class SaveFPRegsModeBits: public BitField<SaveFPRegsMode, 16, 1> {};

   Label slow_;
   RegisterAllocation regs_;
 };


 // Helper to call C++ functions from generated code. The caller must prepare
 // the exit frame before doing the call with GenerateCall.
 class DirectCEntryStub: public PlatformCodeStub {
  public:
   explicit DirectCEntryStub(Isolate* isolate) : PlatformCodeStub(isolate) {}
   void GenerateCall(MacroAssembler* masm, Register target);

  private:
   bool NeedsImmovableCode() override { return true; }

   DEFINE_NULL_CALL_INTERFACE_DESCRIPTOR();
   DEFINE_PLATFORM_CODE_STUB(DirectCEntry, PlatformCodeStub);
 };


 class NameDictionaryLookupStub: public PlatformCodeStub {
  public:
   enum LookupMode { POSITIVE_LOOKUP, NEGATIVE_LOOKUP };

   NameDictionaryLookupStub(Isolate* isolate, LookupMode mode)
       : PlatformCodeStub(isolate) {
     minor_key_ = LookupModeBits::encode(mode);
   }

   static void GenerateNegativeLookup(MacroAssembler* masm,
                                      Label* miss,
                                      Label* done,
                                      Register receiver,
                                      Register properties,
                                      Handle<Name> name,
                                      Register scratch0);

   bool SometimesSetsUpAFrame() override { return false; }

  private:
   static const int kInlinedProbes = 4;
   static const int kTotalProbes = 20;

   static const int kCapacityOffset =
       NameDictionary::kHeaderSize +
       NameDictionary::kCapacityIndex * kPointerSize;

   static const int kElementsStartOffset =
       NameDictionary::kHeaderSize +
       NameDictionary::kElementsStartIndex * kPointerSize;

   LookupMode mode() const { return LookupModeBits::decode(minor_key_); }

   class LookupModeBits: public BitField<LookupMode, 0, 1> {};

   DEFINE_NULL_CALL_INTERFACE_DESCRIPTOR();
   DEFINE_PLATFORM_CODE_STUB(NameDictionaryLookup, PlatformCodeStub);
 };

 }  // namespace internal
 }  // namespace v8

 #endif  // V8_ARM64_CODE_STUBS_ARM64_H_
	// Copyright 2013 the V8 project authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	#ifndef V8_ARM64_CODE_STUBS_ARM64_H_
	#define V8_ARM64_CODE_STUBS_ARM64_H_

	namespace v8 {
	namespace internal {


	class StringHelper : public AllStatic {
	public:
	// Compares two flat one-byte strings and returns result in x0.
	static void GenerateCompareFlatOneByteStrings(
	MacroAssembler* masm, Register left, Register right, Register scratch1,
	Register scratch2, Register scratch3, Register scratch4);

	// Compare two flat one-byte strings for equality and returns result in x0.
	static void GenerateFlatOneByteStringEquals(MacroAssembler* masm,
	Register left, Register right,
	Register scratch1,
	Register scratch2,
	Register scratch3);

	private:
	static void GenerateOneByteCharsCompareLoop(
	MacroAssembler* masm, Register left, Register right, Register length,
	Register scratch1, Register scratch2, Label* chars_not_equal);

	DISALLOW_IMPLICIT_CONSTRUCTORS(StringHelper);
	};


	class RecordWriteStub: public PlatformCodeStub {
	public:
	// Stub to record the write of 'value' at 'address' in 'object'.
	// Typically 'address' = 'object' + <some offset>.
	// See MacroAssembler::RecordWriteField() for example.
	RecordWriteStub(Isolate* isolate,
	Register object,
	Register value,
	Register address,
	RememberedSetAction remembered_set_action,
	SaveFPRegsMode fp_mode)
	: PlatformCodeStub(isolate),
	regs_(object, // An input reg.
	address, // An input reg.
	value) { // One scratch reg.
	DCHECK(object.Is64Bits());
	DCHECK(value.Is64Bits());
	DCHECK(address.Is64Bits());
	minor_key_ = ObjectBits::encode(object.code()) \|
	ValueBits::encode(value.code()) \|
	AddressBits::encode(address.code()) \|
	RememberedSetActionBits::encode(remembered_set_action) \|
	SaveFPRegsModeBits::encode(fp_mode);
	}

	RecordWriteStub(uint32_t key, Isolate* isolate)
	: PlatformCodeStub(key, isolate), regs_(object(), address(), value()) {}

	enum Mode {
	STORE_BUFFER_ONLY,
	INCREMENTAL,
	INCREMENTAL_COMPACTION
	};

	bool SometimesSetsUpAFrame() override { return false; }

	static Mode GetMode(Code* stub);

	static void Patch(Code* stub, Mode mode);

	DEFINE_NULL_CALL_INTERFACE_DESCRIPTOR();

	private:
	// This is a helper class to manage the registers associated with the stub.
	// The 'object' and 'address' registers must be preserved.
	class RegisterAllocation {
	public:
	RegisterAllocation(Register object, Register address, Register scratch);

	void Save(MacroAssembler* masm) {
	// We don't have to save scratch0_ because it was given to us as
	// a scratch register.
	masm->Push(scratch1_, scratch2_);
	}

	void Restore(MacroAssembler* masm) {
	masm->Pop(scratch2_, scratch1_);
	}

	// If we have to call into C then we need to save and restore all caller-
	// saved registers that were not already preserved.
	void SaveCallerSaveRegisters(MacroAssembler* masm, SaveFPRegsMode mode) {
	// TODO(all): This can be very expensive, and it is likely that not every
	// register will need to be preserved. Can we improve this?
	masm->PushCPURegList(saved_regs_);
	if (mode == kSaveFPRegs) {
	masm->PushCPURegList(saved_fp_regs_);
	}
	}

	void RestoreCallerSaveRegisters(MacroAssembler*masm, SaveFPRegsMode mode) {
	// TODO(all): This can be very expensive, and it is likely that not every
	// register will need to be preserved. Can we improve this?
	if (mode == kSaveFPRegs) {
	masm->PopCPURegList(saved_fp_regs_);
	}
	masm->PopCPURegList(saved_regs_);
	}

	Register object() { return object_; }
	Register address() { return address_; }
	Register scratch0() { return scratch0_; }
	Register scratch1() { return scratch1_; }
	Register scratch2() { return scratch2_; }

	private:
	Register object_;
	Register address_;
	Register scratch0_;
	Register scratch1_ = NoReg;
	Register scratch2_ = NoReg;
	CPURegList saved_regs_;
	CPURegList saved_fp_regs_;

	// TODO(all): We should consider moving this somewhere else.
	static CPURegList GetValidRegistersForAllocation() {
	// The list of valid registers for allocation is defined as all the
	// registers without those with a special meaning.
	//
	// The default list excludes registers x26 to x31 because they are
	// reserved for the following purpose:
	// - x26 root register
	// - x27 context pointer register
	// - x28 jssp
	// - x29 frame pointer
	// - x30 link register(lr)
	// - x31 xzr/stack pointer
	CPURegList list(CPURegister::kRegister, kXRegSizeInBits, 0, 25);

	// We also remove MacroAssembler's scratch registers.
	list.Remove(MacroAssembler::DefaultTmpList());

	return list;
	}

	friend class RecordWriteStub;
	};

	enum OnNoNeedToInformIncrementalMarker {
	kReturnOnNoNeedToInformIncrementalMarker,
	kUpdateRememberedSetOnNoNeedToInformIncrementalMarker
	};

	inline Major MajorKey() const final { return RecordWrite; }

	void Generate(MacroAssembler* masm) override;
	void GenerateIncremental(MacroAssembler* masm, Mode mode);
	void CheckNeedsToInformIncrementalMarker(
	MacroAssembler* masm,
	OnNoNeedToInformIncrementalMarker on_no_need,
	Mode mode);
	void InformIncrementalMarker(MacroAssembler* masm);

	void Activate(Code* code) override;

	Register object() const {
	return Register::from_code(ObjectBits::decode(minor_key_));
	}

	Register value() const {
	return Register::from_code(ValueBits::decode(minor_key_));
	}

	Register address() const {
	return Register::from_code(AddressBits::decode(minor_key_));
	}

	RememberedSetAction remembered_set_action() const {
	return RememberedSetActionBits::decode(minor_key_);
	}

	SaveFPRegsMode save_fp_regs_mode() const {
	return SaveFPRegsModeBits::decode(minor_key_);
	}

	class ObjectBits: public BitField<int, 0, 5> {};
	class ValueBits: public BitField<int, 5, 5> {};
	class AddressBits: public BitField<int, 10, 5> {};
	class RememberedSetActionBits: public BitField<RememberedSetAction, 15, 1> {};
	class SaveFPRegsModeBits: public BitField<SaveFPRegsMode, 16, 1> {};

	Label slow_;
	RegisterAllocation regs_;
	};


	// Helper to call C++ functions from generated code. The caller must prepare
	// the exit frame before doing the call with GenerateCall.
	class DirectCEntryStub: public PlatformCodeStub {
	public:
	explicit DirectCEntryStub(Isolate* isolate) : PlatformCodeStub(isolate) {}
	void GenerateCall(MacroAssembler* masm, Register target);

	private:
	bool NeedsImmovableCode() override { return true; }

	DEFINE_NULL_CALL_INTERFACE_DESCRIPTOR();
	DEFINE_PLATFORM_CODE_STUB(DirectCEntry, PlatformCodeStub);
	};


	class NameDictionaryLookupStub: public PlatformCodeStub {
	public:
	enum LookupMode { POSITIVE_LOOKUP, NEGATIVE_LOOKUP };

	NameDictionaryLookupStub(Isolate* isolate, LookupMode mode)
	: PlatformCodeStub(isolate) {
	minor_key_ = LookupModeBits::encode(mode);
	}

	static void GenerateNegativeLookup(MacroAssembler* masm,
	Label* miss,
	Label* done,
	Register receiver,
	Register properties,
	Handle<Name> name,
	Register scratch0);

	bool SometimesSetsUpAFrame() override { return false; }

	private:
	static const int kInlinedProbes = 4;
	static const int kTotalProbes = 20;

	static const int kCapacityOffset =
	NameDictionary::kHeaderSize +
	NameDictionary::kCapacityIndex * kPointerSize;

	static const int kElementsStartOffset =
	NameDictionary::kHeaderSize +
	NameDictionary::kElementsStartIndex * kPointerSize;

	LookupMode mode() const { return LookupModeBits::decode(minor_key_); }

	class LookupModeBits: public BitField<LookupMode, 0, 1> {};

	DEFINE_NULL_CALL_INTERFACE_DESCRIPTOR();
	DEFINE_PLATFORM_CODE_STUB(NameDictionaryLookup, PlatformCodeStub);
	};

	} // namespace internal
	} // namespace v8

	#endif // V8_ARM64_CODE_STUBS_ARM64_H_