Add immediate operands and arithmetic operations to the x64 assembler.

src/x64/assembler-x64-inl.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 26 matching lines @@
   return static_cast<Condition>(cc ^ 1);
 }
 
 
 // -----------------------------------------------------------------------------
 // Implementation of Assembler
 
 #define EMIT(x)                                 \
   *pc_++ = (x)
 
-void Assembler::emit(uint32_t x) {
-  *reinterpret_cast<uint32_t*>(pc_) = x;
+
+void Assembler::emitl(uint32_t x) {
+  Memory::uint32_at(pc_) = x;
   pc_ += sizeof(uint32_t);
 }
 
+
+void Assembler::emitq(uint64_t x, RelocInfo::Mode rmode) {
+  Memory::uint64_at(pc_) = x;
+  RecordRelocInfo(rmode, x);
+}
+
+
+// High bit of reg goes to REX.R, high bit of rm_reg goes to REX.B.
+// REX.W is set.
 void Assembler::emit_rex_64(Register reg, Register rm_reg) {
   EMIT(0x48 | (reg.code() & 0x8) >> 1 | rm_reg.code() >> 3);
 }
 
 
+// The high bit of reg is used for REX.R, the high bit of op's base
+// register is used for REX.B, and the high bit of op's index register
+// is used for REX.X.  REX.W is set.
 void Assembler::emit_rex_64(Register reg, const Operand& op) {
   EMIT(0x48 | (reg.code() & 0x8) >> 1 | op.rex_);
 }
 
 
 void Assembler::set_target_address_at(byte* location, byte* value) {
   UNIMPLEMENTED();
 }
 
 
@@ skipping 157 matching lines @@
   ASSERT(len_ == 1 || len_ == 2);
   int32_t* p = reinterpret_cast<int32_t*>(&buf_[len_]);
   *p = disp;
   len_ += sizeof(int32_t);
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_X64_ASSEMBLER_X64_INL_H_