Combine the incremental-marking write barrier and the remembered-set...

src/ia32/assembler-ia32.h

 // Copyright (c) 1994-2006 Sun Microsystems Inc.
 // 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.
 //
@@ skipping 948 matching lines @@
   // write a comment.
   void RecordComment(const char* msg, bool force = false);
 
   // Writes a single byte or word of data in the code stream.  Used for
   // inline tables, e.g., jump-tables.
   void db(uint8_t data);
   void dd(uint32_t data);
 
   int pc_offset() const { return pc_ - buffer_; }
 
+  // Used for patching the code stream while it is being emitted.
+  inline byte get_opcode(int offset) {
+    ASSERT(offset < 0);
+    ASSERT(pc_ + offset >= buffer_);
+    return pc_[offset];
+  }
+  inline void set_opcode(int offset, byte opcode) {
+    ASSERT(offset < 0);
+    ASSERT(pc_ + offset >= buffer_);
+    pc_[offset] = opcode;
+  }
+
   // Check if there is less than kGap bytes available in the buffer.
   // If this is the case, we need to grow the buffer before emitting
   // an instruction or relocation information.
   inline bool overflow() const { return pc_ >= reloc_info_writer.pos() - kGap; }
 
   // Get the number of bytes available in the buffer.
   inline int available_space() const { return reloc_info_writer.pos() - pc_; }
 
   static bool IsNop(Address addr) { return *addr == 0x90; }
 
@@ skipping 11 matching lines @@
   bool emit_debug_code() const { return emit_debug_code_; }
 
   void movsd(XMMRegister dst, const Operand& src);
   void movsd(const Operand& dst, XMMRegister src);
 
   void emit_sse_operand(XMMRegister reg, const Operand& adr);
   void emit_sse_operand(XMMRegister dst, XMMRegister src);
   void emit_sse_operand(Register dst, XMMRegister src);
 
   byte* addr_at(int pos)  { return buffer_ + pos; }
+
  private:
   byte byte_at(int pos)  { return buffer_[pos]; }
   void set_byte_at(int pos, byte value) { buffer_[pos] = value; }
   uint32_t long_at(int pos)  {
     return *reinterpret_cast<uint32_t*>(addr_at(pos));
   }
   void long_at_put(int pos, uint32_t x)  {
     *reinterpret_cast<uint32_t*>(addr_at(pos)) = x;
   }
 
@@ skipping 83 matching lines @@
  private:
   Assembler* assembler_;
 #ifdef DEBUG
   int space_before_;
 #endif
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_IA32_ASSEMBLER_IA32_H_