Merge experimental/a64 to bleeding_edge.

src/a64/regexp-macro-assembler-a64.h

-// Copyright 2012 the V8 project authors. All rights reserved.
+// Copyright 2013 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.
 
-#ifndef V8_ARM_REGEXP_MACRO_ASSEMBLER_ARM_H_
-#define V8_ARM_REGEXP_MACRO_ASSEMBLER_ARM_H_
+#ifndef V8_A64_REGEXP_MACRO_ASSEMBLER_A64_H_
+#define V8_A64_REGEXP_MACRO_ASSEMBLER_A64_H_
 
-#include "arm/assembler-arm.h"
-#include "arm/assembler-arm-inl.h"
+#include "a64/assembler-a64.h"
+#include "a64/assembler-a64-inl.h"
 #include "macro-assembler.h"
 
 namespace v8 {
 namespace internal {
 
 
 #ifndef V8_INTERPRETED_REGEXP
-class RegExpMacroAssemblerARM: public NativeRegExpMacroAssembler {
+class RegExpMacroAssemblerA64: public NativeRegExpMacroAssembler {
  public:
-  RegExpMacroAssemblerARM(Mode mode, int registers_to_save, Zone* zone);
-  virtual ~RegExpMacroAssemblerARM();
+  RegExpMacroAssemblerA64(Mode mode, int registers_to_save, Zone* zone);
+  virtual ~RegExpMacroAssemblerA64();
   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(Label* on_not_at_start);
   virtual void CheckNotBackReference(int start_reg, Label* on_no_match);
   virtual void CheckNotBackReferenceIgnoreCase(int start_reg,
                                                Label* on_no_match);
   virtual void CheckNotCharacter(unsigned c, Label* on_not_equal);
   virtual void CheckNotCharacterAfterAnd(unsigned c,
                                          unsigned mask,
@@ skipping 40 matching lines @@
   virtual void WriteCurrentPositionToRegister(int reg, int cp_offset);
   virtual void ClearRegisters(int reg_from, int reg_to);
   virtual void WriteStackPointerToRegister(int reg);
   virtual bool CanReadUnaligned();
 
   // 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);
+                                  Address re_frame,
+                                  int start_offset,
+                                  const byte** input_start,
+                                  const byte** input_end);
 
  private:
-  // Offsets from frame_pointer() of function parameters and stored registers.
-  static const int kFramePointer = 0;
-
   // Above the frame pointer - Stored registers and stack passed parameters.
-  // Register 4..11.
-  static const int kStoredRegisters = kFramePointer;
-  // Return address (stored from link register, read into pc on return).
-  static const int kReturnAddress = kStoredRegisters + 8 * kPointerSize;
+  // 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;
   static const int kSecondaryReturnAddress = kReturnAddress + kPointerSize;
-  // Stack parameters placed by caller.
-  static const int kRegisterOutput = kSecondaryReturnAddress + kPointerSize;
-  static const int kNumOutputRegisters = kRegisterOutput + kPointerSize;
-  static const int kStackHighEnd = kNumOutputRegisters + kPointerSize;
-  static const int kDirectCall = kStackHighEnd + kPointerSize;
-  static const int kIsolate = kDirectCall + kPointerSize;
+  // Stack parameter placed by caller.
+  static const int kIsolate = kSecondaryReturnAddress + kPointerSize;
 
   // Below the frame pointer.
   // Register parameters stored by setup code.
-  static const int kInputEnd = kFramePointer - kPointerSize;
-  static const int kInputStart = kInputEnd - kPointerSize;
-  static const int kStartIndex = kInputStart - kPointerSize;
-  static const int kInputString = kStartIndex - kPointerSize;
+  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 kSuccessfulCaptures = kInputString - kPointerSize;
-  static const int kInputStartMinusOne = kSuccessfulCaptures - kPointerSize;
-  // First register address. Following registers are below it on the stack.
-  static const int kRegisterZero = kInputStartMinusOne - kPointerSize;
+  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 - kWRegSizeInBytes;
+  // A capture is a 64 bit value holding two position.
+  static const int kFirstCaptureOnStack = kSuccessCounter - kXRegSizeInBytes;
 
   // Initial size of code buffer.
   static const size_t kRegExpCodeSize = 1024;
 
-  static const int kBacktrackConstantPoolSize = 4;
+  // 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);
 
-  // The ebp-relative location of a regexp register.
+  // 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.
-  inline Register current_input_offset() { return r6; }
+  Register current_input_offset() { return w21; }
 
   // The register containing the current character after LoadCurrentCharacter.
-  inline Register current_character() { return r7; }
+  Register current_character() { return w22; }
 
   // Register holding address of the end of the input string.
-  inline Register end_of_input_address() { return r10; }
+  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.
-  inline Register frame_pointer() { return fp; }
+  Register frame_pointer() { return fp; }
 
   // The register containing the backtrack stack top. Provides a meaningful
   // name to the register.
-  inline Register backtrack_stackpointer() { return r8; }
+  Register backtrack_stackpointer() { return x23; }
 
   // Register holding pointer to the current code object.
-  inline Register code_pointer() { return r5; }
+  Register code_pointer() { return x20; }
+
+  // Register holding the value used for clearing capture registers.
+  Register non_position_value() { 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)
-  inline int char_size() { return static_cast<int>(mode_); }
+  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);
 
-  // Call and return internally in the generated code in a way that
-  // is GC-safe (i.e., doesn't leave absolute code addresses on the stack)
-  inline void SafeCall(Label* to, Condition cond = al);
-  inline void SafeReturn();
-  inline void SafeCallTarget(Label* name);
+  // 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) {
+    ASSERT(register_index >= 0);
+    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 (ASCII 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 v8::internal
 
-#endif  // V8_ARM_REGEXP_MACRO_ASSEMBLER_ARM_H_
+#endif  // V8_A64_REGEXP_MACRO_ASSEMBLER_A64_H_