X64 implementation: Add high_bit() and low_bits() to register methods.

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 52 matching lines @@
 }
 
 
 void Assembler::emitw(uint16_t x) {
   Memory::uint16_at(pc_) = x;
   pc_ += sizeof(uint16_t);
 }
 
 
 void Assembler::emit_rex_64(Register reg, Register rm_reg) {
-  emit(0x48 | (reg.code() & 0x8) >> 1 | rm_reg.code() >> 3);
+  emit(0x48 | reg.high_bit() << 2 | rm_reg.high_bit());
 }
 
 
 void Assembler::emit_rex_64(Register reg, const Operand& op) {
-  emit(0x48 | (reg.code() & 0x8) >> 1 | op.rex_);
+  emit(0x48 | reg.high_bit() << 2 | op.rex_);
 }
 
 
 void Assembler::emit_rex_64(Register rm_reg) {
   ASSERT_EQ(rm_reg.code() & 0xf, rm_reg.code());
-  emit(0x48 | (rm_reg.code() >> 3));
+  emit(0x48 | rm_reg.high_bit());
 }
 
 
 void Assembler::emit_rex_64(const Operand& op) {
   emit(0x48 | op.rex_);
 }
 
 
 void Assembler::emit_rex_32(Register reg, Register rm_reg) {
-  emit(0x40 | (reg.code() & 0x8) >> 1 | rm_reg.code() >> 3);
+  emit(0x40 | reg.high_bit() << 2 | rm_reg.high_bit());
 }
 
 
 void Assembler::emit_rex_32(Register reg, const Operand& op) {
-  emit(0x40 | (reg.code() & 0x8) >> 1 | op.rex_);
+  emit(0x40 | reg.high_bit() << 2  | op.rex_);
 }
 
 
 void Assembler::emit_rex_32(Register rm_reg) {
-  emit(0x40 | (rm_reg.code() & 0x8) >> 3);
+  emit(0x40 | rm_reg.high_bit());
 }
 
 
 void Assembler::emit_rex_32(const Operand& op) {
   emit(0x40 | op.rex_);
 }
 
 
 void Assembler::emit_optional_rex_32(Register reg, Register rm_reg) {
-  byte rex_bits = (reg.code() & 0x8) >> 1 | rm_reg.code() >> 3;
+  byte rex_bits = reg.high_bit() << 2 | rm_reg.high_bit();
   if (rex_bits != 0) emit(0x40 | rex_bits);
 }
 
 
 void Assembler::emit_optional_rex_32(Register reg, const Operand& op) {
-  byte rex_bits =  (reg.code() & 0x8) >> 1 | op.rex_;
+  byte rex_bits =  reg.high_bit() << 2 | op.rex_;
   if (rex_bits != 0) emit(0x40 | rex_bits);
 }
 
 
 void Assembler::emit_optional_rex_32(Register rm_reg) {
-  if (rm_reg.code() > 0x7) emit(0x41);
+  if (rm_reg.high_bit()) emit(0x41);
 }
 
 
 void Assembler::emit_optional_rex_32(const Operand& op) {
   if (op.rex_ != 0) emit(0x40 | op.rex_);
 }
 
 
 Address Assembler::target_address_at(Address pc) {
   return Memory::Address_at(pc);
@@ skipping 100 matching lines @@
 
 Object** RelocInfo::call_object_address() {
   UNIMPLEMENTED();  // IA32 code below.
   ASSERT(IsCallInstruction());
   return reinterpret_cast<Object**>(pc_ + 1);
 }
 
 // -----------------------------------------------------------------------------
 // Implementation of Operand
 
-void Operand::set_modrm(int mod, Register rm) {
-  ASSERT((mod & -4) == 0);
-  buf_[0] = (mod << 6) | (rm.code() & 0x7);
+void Operand::set_modrm(int mod, Register rm_reg) {
+  ASSERT(is_uint2(mod));
+  buf_[0] = mod << 6 | rm_reg.low_bits();
   // Set REX.B to the high bit of rm.code().
-  rex_ |= (rm.code() >> 3);
+  rex_ |= rm_reg.high_bit();
 }
 
 
 void Operand::set_sib(ScaleFactor scale, Register index, Register base) {
   ASSERT(len_ == 1);
   ASSERT(is_uint2(scale));
   // Use SIB with no index register only for base rsp or r12. Otherwise we
   // would skip the SIB byte entirely.
   ASSERT(!index.is(rsp) || base.is(rsp) || base.is(r12));
-  buf_[1] = scale << 6 | (index.code() & 0x7) << 3 | (base.code() & 0x7);
-  rex_ |= (index.code() >> 3) << 1 | base.code() >> 3;
+  buf_[1] = scale << 6 | index.low_bits() << 3 | base.low_bits();
+  rex_ |= index.high_bit() << 1 | base.high_bit();
   len_ = 2;
 }
 
 void Operand::set_disp8(int disp) {
   ASSERT(is_int8(disp));
   ASSERT(len_ == 1 || len_ == 2);
   int8_t* p = reinterpret_cast<int8_t*>(&buf_[len_]);
   *p = disp;
   len_ += sizeof(int8_t);
 }
 
 void Operand::set_disp32(int disp) {
   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_