X64 RegExp - fix RegExp on WIN64.

src/x64/regexp-macro-assembler-x64.h

 // Copyright 2009 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
@@ skipping 111 matching lines @@
                                   Code* re_code,
                                   Address re_frame);
 
  private:
   // Offsets from rbp of function parameters and stored registers.
   static const int kFramePointer = 0;
   // Above the frame pointer - function parameters and return address.
   static const int kReturn_eip = kFramePointer + kPointerSize;
   static const int kFrameAlign = kReturn_eip + kPointerSize;
 
-#ifdef __MSVC__
+#ifdef _WIN64
   // Parameters (first four passed as registers, but with room on stack).
   // In Microsoft 64-bit Calling Convention, there is room on the callers
   // stack (before the return address) to spill parameter registers. We
   // use this space to store the register passed parameters.
   static const int kInputString = kFrameAlign;
+  // StartIndex is passed as 32 bit int.
   static const int kStartIndex = kInputString + kPointerSize;
   static const int kInputStart = kStartIndex + kPointerSize;
   static const int kInputEnd = kInputStart + kPointerSize;
   static const int kRegisterOutput = kInputEnd + kPointerSize;
+  // AtStart is passed as 32 bit int (values 0 or 1).
   static const int kAtStart = kRegisterOutput + kPointerSize;
   static const int kStackHighEnd = kAtStart + kPointerSize;
 #else
   // In AMD64 ABI Calling Convention, the first six integer parameters
   // are passed as registers, and caller must allocate space on the stack
   // if it wants them stored. We push the parameters after the frame pointer.
   static const int kInputString = kFramePointer - kPointerSize;
   static const int kStartIndex = kInputString - kPointerSize;
   static const int kInputStart = kStartIndex - kPointerSize;
   static const int kInputEnd = kInputStart - kPointerSize;
   static const int kRegisterOutput = kInputEnd - kPointerSize;
   static const int kAtStart = kRegisterOutput - kPointerSize;
   static const int kStackHighEnd = kFrameAlign;
 #endif
 
-#ifdef __MSVC__
+#ifdef _WIN64
   // Microsoft calling convention has three callee-saved registers
   // (that we are using). We push these after the frame pointer.
   static const int kBackup_rsi = kFramePointer - kPointerSize;
   static const int kBackup_rdi = kBackup_rsi - kPointerSize;
   static const int kBackup_rbx = kBackup_rdi - kPointerSize;
   static const int kLastCalleeSaveRegister = kBackup_rbx;
 #else
   // AMD64 Calling Convention has only one callee-save register that
   // we use. We push this after the frame pointer (and after the
   // parameters).
@@ skipping 115 matching lines @@
   Label exit_label_;
   Label check_preempt_label_;
   Label stack_overflow_label_;
 };
 
 #endif  // V8_NATIVE_REGEXP
 
 }}  // namespace v8::internal
 
 #endif  // V8_X64_REGEXP_MACRO_ASSEMBLER_X64_H_