src/v8/src/regexp/arm64/regexp-macro-assembler-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_REGEXP_ARM64_REGEXP_MACRO_ASSEMBLER_ARM64_H_
 #define V8_REGEXP_ARM64_REGEXP_MACRO_ASSEMBLER_ARM64_H_

 #include "src/arm64/assembler-arm64.h"
 #include "src/macro-assembler.h"
 #include "src/regexp/regexp-macro-assembler.h"

 namespace v8 {
 namespace internal {


 #ifndef V8_INTERPRETED_REGEXP
 class RegExpMacroAssemblerARM64: public NativeRegExpMacroAssembler {
  public:
   RegExpMacroAssemblerARM64(Isolate* isolate, Zone* zone, Mode mode,
                             int registers_to_save);
   virtual ~RegExpMacroAssemblerARM64();
   virtual void AbortedCodeGeneration() { masm_->AbortedCodeGeneration(); }
   virtual int stack_limit_slack();
   virtual void AdvanceCurrentPosition(int by);
   virtual void AdvanceRegister(int reg, int by);
   virtual void Backtrack();
   virtual void Bind(Label* label);
   virtual void CheckAtStart(Label* on_at_start);
   virtual void CheckCharacter(unsigned c, Label* on_equal);
   virtual void CheckCharacterAfterAnd(unsigned c,
                                       unsigned mask,
                                       Label* on_equal);
   virtual void CheckCharacterGT(uc16 limit, Label* on_greater);
   virtual void CheckCharacterLT(uc16 limit, Label* on_less);
   virtual void CheckCharacters(Vector<const uc16> str,
                                int cp_offset,
                                Label* on_failure,
                                bool check_end_of_string);
   // A "greedy loop" is a loop that is both greedy and with a simple
   // body. It has a particularly simple implementation.
   virtual void CheckGreedyLoop(Label* on_tos_equals_current_position);
   virtual void CheckNotAtStart(int cp_offset, Label* on_not_at_start);
   virtual void CheckNotBackReference(int start_reg, bool read_backward,
                                      Label* on_no_match);
   virtual void CheckNotBackReferenceIgnoreCase(int start_reg,
                                                bool read_backward, bool unicode,
                                                Label* on_no_match);
   virtual void CheckNotCharacter(unsigned c, Label* on_not_equal);
   virtual void CheckNotCharacterAfterAnd(unsigned c,
                                          unsigned mask,
                                          Label* on_not_equal);
   virtual void CheckNotCharacterAfterMinusAnd(uc16 c,
                                               uc16 minus,
                                               uc16 mask,
                                               Label* on_not_equal);
   virtual void CheckCharacterInRange(uc16 from,
                                      uc16 to,
                                      Label* on_in_range);
   virtual void CheckCharacterNotInRange(uc16 from,
                                         uc16 to,
                                         Label* on_not_in_range);
   virtual void CheckBitInTable(Handle<ByteArray> table, Label* on_bit_set);

   // Checks whether the given offset from the current position is before
   // the end of the string.
   virtual void CheckPosition(int cp_offset, Label* on_outside_input);
   virtual bool CheckSpecialCharacterClass(uc16 type,
                                           Label* on_no_match);
   virtual void Fail();
   virtual Handle<HeapObject> GetCode(Handle<String> source);
   virtual void GoTo(Label* label);
   virtual void IfRegisterGE(int reg, int comparand, Label* if_ge);
   virtual void IfRegisterLT(int reg, int comparand, Label* if_lt);
   virtual void IfRegisterEqPos(int reg, Label* if_eq);
   virtual IrregexpImplementation Implementation();
   virtual void LoadCurrentCharacter(int cp_offset,
                                     Label* on_end_of_input,
                                     bool check_bounds = true,
                                     int characters = 1);
   virtual void PopCurrentPosition();
   virtual void PopRegister(int register_index);
   virtual void PushBacktrack(Label* label);
   virtual void PushCurrentPosition();
   virtual void PushRegister(int register_index,
                             StackCheckFlag check_stack_limit);
   virtual void ReadCurrentPositionFromRegister(int reg);
   virtual void ReadStackPointerFromRegister(int reg);
   virtual void SetCurrentPositionFromEnd(int by);
   virtual void SetRegister(int register_index, int to);
   virtual bool Succeed();
   virtual void WriteCurrentPositionToRegister(int reg, int cp_offset);
   virtual void ClearRegisters(int reg_from, int reg_to);
   virtual void WriteStackPointerToRegister(int reg);

   // Called from RegExp if the stack-guard is triggered.
   // If the code object is relocated, the return address is fixed before
   // returning.
   static int CheckStackGuardState(Address* return_address,
                                   Code* re_code,
                                   Address re_frame,
                                   int start_offset,
                                   const byte** input_start,
                                   const byte** input_end);

  private:
   // Above the frame pointer - Stored registers and stack passed parameters.
   // Callee-saved registers x19-x29, where x29 is the old frame pointer.
   static const int kCalleeSavedRegisters = 0;
   // Return address.
   // It is placed above the 11 callee-saved registers.
   static const int kReturnAddress = kCalleeSavedRegisters + 11 * kPointerSize;
   // Stack parameter placed by caller.
   static const int kIsolate = kReturnAddress + kPointerSize;

   // Below the frame pointer.
   // Register parameters stored by setup code.
   static const int kDirectCall = kCalleeSavedRegisters - kPointerSize;
   static const int kStackBase = kDirectCall - kPointerSize;
   static const int kOutputSize = kStackBase - kPointerSize;
   static const int kInput = kOutputSize - kPointerSize;
   // When adding local variables remember to push space for them in
   // the frame in GetCode.
   static const int kSuccessCounter = kInput - kPointerSize;
   // First position register address on the stack. Following positions are
   // below it. A position is a 32 bit value.
   static const int kFirstRegisterOnStack = kSuccessCounter - kWRegSize;
   // A capture is a 64 bit value holding two position.
   static const int kFirstCaptureOnStack = kSuccessCounter - kXRegSize;

   // Initial size of code buffer.
   static const size_t kRegExpCodeSize = 1024;

   // When initializing registers to a non-position value we can unroll
   // the loop. Set the limit of registers to unroll.
   static const int kNumRegistersToUnroll = 16;

   // We are using x0 to x7 as a register cache. Each hardware register must
   // contain one capture, that is two 32 bit registers. We can cache at most
   // 16 registers.
   static const int kNumCachedRegisters = 16;

   // Load a number of characters at the given offset from the
   // current position, into the current-character register.
   void LoadCurrentCharacterUnchecked(int cp_offset, int character_count);

   // Check whether preemption has been requested.
   void CheckPreemption();

   // Check whether we are exceeding the stack limit on the backtrack stack.
   void CheckStackLimit();

   // Generate a call to CheckStackGuardState.
   void CallCheckStackGuardState(Register scratch);

   // Location of a 32 bit position register.
   MemOperand register_location(int register_index);

   // Location of a 64 bit capture, combining two position registers.
   MemOperand capture_location(int register_index, Register scratch);

   // Register holding the current input position as negative offset from
   // the end of the string.
   Register current_input_offset() { return w21; }

   // The register containing the current character after LoadCurrentCharacter.
   Register current_character() { return w22; }

   // Register holding address of the end of the input string.
   Register input_end() { return x25; }

   // Register holding address of the start of the input string.
   Register input_start() { return x26; }

   // Register holding the offset from the start of the string where we should
   // start matching.
   Register start_offset() { return w27; }

   // Pointer to the output array's first element.
   Register output_array() { return x28; }

   // Register holding the frame address. Local variables, parameters and
   // regexp registers are addressed relative to this.
   Register frame_pointer() { return fp; }

   // The register containing the backtrack stack top. Provides a meaningful
   // name to the register.
   Register backtrack_stackpointer() { return x23; }

   // Register holding pointer to the current code object.
   Register code_pointer() { return x20; }

   // Register holding the value used for clearing capture registers.
   Register string_start_minus_one() { return w24; }
   // The top 32 bit of this register is used to store this value
   // twice. This is used for clearing more than one register at a time.
   Register twice_non_position_value() { return x24; }

   // Byte size of chars in the string to match (decided by the Mode argument)
   int char_size() { return static_cast<int>(mode_); }

   // Equivalent to a conditional branch to the label, unless the label
   // is NULL, in which case it is a conditional Backtrack.
   void BranchOrBacktrack(Condition condition, Label* to);

   // Compares reg against immmediate before calling BranchOrBacktrack.
   // It makes use of the Cbz and Cbnz instructions.
   void CompareAndBranchOrBacktrack(Register reg,
                                    int immediate,
                                    Condition condition,
                                    Label* to);

   inline void CallIf(Label* to, Condition condition);

   // Save and restore the link register on the stack in a way that
   // is GC-safe.
   inline void SaveLinkRegister();
   inline void RestoreLinkRegister();

   // Pushes the value of a register on the backtrack stack. Decrements the
   // stack pointer by a word size and stores the register's value there.
   inline void Push(Register source);

   // Pops a value from the backtrack stack. Reads the word at the stack pointer
   // and increments it by a word size.
   inline void Pop(Register target);

   // This state indicates where the register actually is.
   enum RegisterState {
     STACKED,     // Resides in memory.
     CACHED_LSW,  // Least Significant Word of a 64 bit hardware register.
     CACHED_MSW   // Most Significant Word of a 64 bit hardware register.
   };

   RegisterState GetRegisterState(int register_index) {
     DCHECK_LE(0, register_index);
     if (register_index >= kNumCachedRegisters) {
       return STACKED;
     } else {
       if ((register_index % 2) == 0) {
         return CACHED_LSW;
       } else {
         return CACHED_MSW;
       }
     }
   }

   // Store helper that takes the state of the register into account.
   inline void StoreRegister(int register_index, Register source);

   // Returns a hardware W register that holds the value of the capture
   // register.
   //
   // This function will try to use an existing cache register (w0-w7) for the
   // result. Otherwise, it will load the value into maybe_result.
   //
   // If the returned register is anything other than maybe_result, calling code
   // must not write to it.
   inline Register GetRegister(int register_index, Register maybe_result);

   // Returns the harware register (x0-x7) holding the value of the capture
   // register.
   // This assumes that the state of the register is not STACKED.
   inline Register GetCachedRegister(int register_index);

   Isolate* isolate() const { return masm_->isolate(); }

   MacroAssembler* masm_;

   // Which mode to generate code for (LATIN1 or UC16).
   Mode mode_;

   // One greater than maximal register index actually used.
   int num_registers_;

   // Number of registers to output at the end (the saved registers
   // are always 0..num_saved_registers_-1)
   int num_saved_registers_;

   // Labels used internally.
   Label entry_label_;
   Label start_label_;
   Label success_label_;
   Label backtrack_label_;
   Label exit_label_;
   Label check_preempt_label_;
   Label stack_overflow_label_;
 };

 #endif  // V8_INTERPRETED_REGEXP


 }  // namespace internal
 }  // namespace v8

 #endif  // V8_REGEXP_ARM64_REGEXP_MACRO_ASSEMBLER_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_REGEXP_ARM64_REGEXP_MACRO_ASSEMBLER_ARM64_H_
	#define V8_REGEXP_ARM64_REGEXP_MACRO_ASSEMBLER_ARM64_H_

	#include "src/arm64/assembler-arm64.h"
	#include "src/macro-assembler.h"
	#include "src/regexp/regexp-macro-assembler.h"

	namespace v8 {
	namespace internal {


	#ifndef V8_INTERPRETED_REGEXP
	class RegExpMacroAssemblerARM64: public NativeRegExpMacroAssembler {
	public:
	RegExpMacroAssemblerARM64(Isolate* isolate, Zone* zone, Mode mode,
	int registers_to_save);
	virtual ~RegExpMacroAssemblerARM64();
	virtual void AbortedCodeGeneration() { masm_->AbortedCodeGeneration(); }
	virtual int stack_limit_slack();
	virtual void AdvanceCurrentPosition(int by);
	virtual void AdvanceRegister(int reg, int by);
	virtual void Backtrack();
	virtual void Bind(Label* label);
	virtual void CheckAtStart(Label* on_at_start);
	virtual void CheckCharacter(unsigned c, Label* on_equal);
	virtual void CheckCharacterAfterAnd(unsigned c,
	unsigned mask,
	Label* on_equal);
	virtual void CheckCharacterGT(uc16 limit, Label* on_greater);
	virtual void CheckCharacterLT(uc16 limit, Label* on_less);
	virtual void CheckCharacters(Vector<const uc16> str,
	int cp_offset,
	Label* on_failure,
	bool check_end_of_string);
	// A "greedy loop" is a loop that is both greedy and with a simple
	// body. It has a particularly simple implementation.
	virtual void CheckGreedyLoop(Label* on_tos_equals_current_position);
	virtual void CheckNotAtStart(int cp_offset, Label* on_not_at_start);
	virtual void CheckNotBackReference(int start_reg, bool read_backward,
	Label* on_no_match);
	virtual void CheckNotBackReferenceIgnoreCase(int start_reg,
	bool read_backward, bool unicode,
	Label* on_no_match);
	virtual void CheckNotCharacter(unsigned c, Label* on_not_equal);
	virtual void CheckNotCharacterAfterAnd(unsigned c,
	unsigned mask,
	Label* on_not_equal);
	virtual void CheckNotCharacterAfterMinusAnd(uc16 c,
	uc16 minus,
	uc16 mask,
	Label* on_not_equal);
	virtual void CheckCharacterInRange(uc16 from,
	uc16 to,
	Label* on_in_range);
	virtual void CheckCharacterNotInRange(uc16 from,
	uc16 to,
	Label* on_not_in_range);
	virtual void CheckBitInTable(Handle<ByteArray> table, Label* on_bit_set);

	// Checks whether the given offset from the current position is before
	// the end of the string.
	virtual void CheckPosition(int cp_offset, Label* on_outside_input);
	virtual bool CheckSpecialCharacterClass(uc16 type,
	Label* on_no_match);
	virtual void Fail();
	virtual Handle<HeapObject> GetCode(Handle<String> source);
	virtual void GoTo(Label* label);
	virtual void IfRegisterGE(int reg, int comparand, Label* if_ge);
	virtual void IfRegisterLT(int reg, int comparand, Label* if_lt);
	virtual void IfRegisterEqPos(int reg, Label* if_eq);
	virtual IrregexpImplementation Implementation();
	virtual void LoadCurrentCharacter(int cp_offset,
	Label* on_end_of_input,
	bool check_bounds = true,
	int characters = 1);
	virtual void PopCurrentPosition();
	virtual void PopRegister(int register_index);
	virtual void PushBacktrack(Label* label);
	virtual void PushCurrentPosition();
	virtual void PushRegister(int register_index,
	StackCheckFlag check_stack_limit);
	virtual void ReadCurrentPositionFromRegister(int reg);
	virtual void ReadStackPointerFromRegister(int reg);
	virtual void SetCurrentPositionFromEnd(int by);
	virtual void SetRegister(int register_index, int to);
	virtual bool Succeed();
	virtual void WriteCurrentPositionToRegister(int reg, int cp_offset);
	virtual void ClearRegisters(int reg_from, int reg_to);
	virtual void WriteStackPointerToRegister(int reg);

	// Called from RegExp if the stack-guard is triggered.
	// If the code object is relocated, the return address is fixed before
	// returning.
	static int CheckStackGuardState(Address* return_address,
	Code* re_code,
	Address re_frame,
	int start_offset,
	const byte** input_start,
	const byte** input_end);

	private:
	// Above the frame pointer - Stored registers and stack passed parameters.
	// Callee-saved registers x19-x29, where x29 is the old frame pointer.
	static const int kCalleeSavedRegisters = 0;
	// Return address.
	// It is placed above the 11 callee-saved registers.
	static const int kReturnAddress = kCalleeSavedRegisters + 11 * kPointerSize;
	// Stack parameter placed by caller.
	static const int kIsolate = kReturnAddress + kPointerSize;

	// Below the frame pointer.
	// Register parameters stored by setup code.
	static const int kDirectCall = kCalleeSavedRegisters - kPointerSize;
	static const int kStackBase = kDirectCall - kPointerSize;
	static const int kOutputSize = kStackBase - kPointerSize;
	static const int kInput = kOutputSize - kPointerSize;
	// When adding local variables remember to push space for them in
	// the frame in GetCode.
	static const int kSuccessCounter = kInput - kPointerSize;
	// First position register address on the stack. Following positions are
	// below it. A position is a 32 bit value.
	static const int kFirstRegisterOnStack = kSuccessCounter - kWRegSize;
	// A capture is a 64 bit value holding two position.
	static const int kFirstCaptureOnStack = kSuccessCounter - kXRegSize;

	// Initial size of code buffer.
	static const size_t kRegExpCodeSize = 1024;

	// When initializing registers to a non-position value we can unroll
	// the loop. Set the limit of registers to unroll.
	static const int kNumRegistersToUnroll = 16;

	// We are using x0 to x7 as a register cache. Each hardware register must
	// contain one capture, that is two 32 bit registers. We can cache at most
	// 16 registers.
	static const int kNumCachedRegisters = 16;

	// Load a number of characters at the given offset from the
	// current position, into the current-character register.
	void LoadCurrentCharacterUnchecked(int cp_offset, int character_count);

	// Check whether preemption has been requested.
	void CheckPreemption();

	// Check whether we are exceeding the stack limit on the backtrack stack.
	void CheckStackLimit();

	// Generate a call to CheckStackGuardState.
	void CallCheckStackGuardState(Register scratch);

	// Location of a 32 bit position register.
	MemOperand register_location(int register_index);

	// Location of a 64 bit capture, combining two position registers.
	MemOperand capture_location(int register_index, Register scratch);

	// Register holding the current input position as negative offset from
	// the end of the string.
	Register current_input_offset() { return w21; }

	// The register containing the current character after LoadCurrentCharacter.
	Register current_character() { return w22; }

	// Register holding address of the end of the input string.
	Register input_end() { return x25; }

	// Register holding address of the start of the input string.
	Register input_start() { return x26; }

	// Register holding the offset from the start of the string where we should
	// start matching.
	Register start_offset() { return w27; }

	// Pointer to the output array's first element.
	Register output_array() { return x28; }

	// Register holding the frame address. Local variables, parameters and
	// regexp registers are addressed relative to this.
	Register frame_pointer() { return fp; }

	// The register containing the backtrack stack top. Provides a meaningful
	// name to the register.
	Register backtrack_stackpointer() { return x23; }

	// Register holding pointer to the current code object.
	Register code_pointer() { return x20; }

	// Register holding the value used for clearing capture registers.
	Register string_start_minus_one() { return w24; }
	// The top 32 bit of this register is used to store this value
	// twice. This is used for clearing more than one register at a time.
	Register twice_non_position_value() { return x24; }

	// Byte size of chars in the string to match (decided by the Mode argument)
	int char_size() { return static_cast<int>(mode_); }

	// Equivalent to a conditional branch to the label, unless the label
	// is NULL, in which case it is a conditional Backtrack.
	void BranchOrBacktrack(Condition condition, Label* to);

	// Compares reg against immmediate before calling BranchOrBacktrack.
	// It makes use of the Cbz and Cbnz instructions.
	void CompareAndBranchOrBacktrack(Register reg,
	int immediate,
	Condition condition,
	Label* to);

	inline void CallIf(Label* to, Condition condition);

	// Save and restore the link register on the stack in a way that
	// is GC-safe.
	inline void SaveLinkRegister();
	inline void RestoreLinkRegister();

	// Pushes the value of a register on the backtrack stack. Decrements the
	// stack pointer by a word size and stores the register's value there.
	inline void Push(Register source);

	// Pops a value from the backtrack stack. Reads the word at the stack pointer
	// and increments it by a word size.
	inline void Pop(Register target);

	// This state indicates where the register actually is.
	enum RegisterState {
	STACKED, // Resides in memory.
	CACHED_LSW, // Least Significant Word of a 64 bit hardware register.
	CACHED_MSW // Most Significant Word of a 64 bit hardware register.
	};

	RegisterState GetRegisterState(int register_index) {
	DCHECK_LE(0, register_index);
	if (register_index >= kNumCachedRegisters) {
	return STACKED;
	} else {
	if ((register_index % 2) == 0) {
	return CACHED_LSW;
	} else {
	return CACHED_MSW;
	}
	}
	}

	// Store helper that takes the state of the register into account.
	inline void StoreRegister(int register_index, Register source);

	// Returns a hardware W register that holds the value of the capture
	// register.
	//
	// This function will try to use an existing cache register (w0-w7) for the
	// result. Otherwise, it will load the value into maybe_result.
	//
	// If the returned register is anything other than maybe_result, calling code
	// must not write to it.
	inline Register GetRegister(int register_index, Register maybe_result);

	// Returns the harware register (x0-x7) holding the value of the capture
	// register.
	// This assumes that the state of the register is not STACKED.
	inline Register GetCachedRegister(int register_index);

	Isolate* isolate() const { return masm_->isolate(); }

	MacroAssembler* masm_;

	// Which mode to generate code for (LATIN1 or UC16).
	Mode mode_;

	// One greater than maximal register index actually used.
	int num_registers_;

	// Number of registers to output at the end (the saved registers
	// are always 0..num_saved_registers_-1)
	int num_saved_registers_;

	// Labels used internally.
	Label entry_label_;
	Label start_label_;
	Label success_label_;
	Label backtrack_label_;
	Label exit_label_;
	Label check_preempt_label_;
	Label stack_overflow_label_;
	};

	#endif // V8_INTERPRETED_REGEXP


	} // namespace internal
	} // namespace v8

	#endif // V8_REGEXP_ARM64_REGEXP_MACRO_ASSEMBLER_ARM64_H_