Revert of Remove register index/code indirection

src/arm64/assembler-arm64.cc

 // 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
@@ skipping 17 matching lines @@
 
 #if V8_TARGET_ARCH_ARM64
 
 #define ARM64_DEFINE_REG_STATICS
 #include "src/arm64/assembler-arm64.h"
 
 #include "src/arm64/assembler-arm64-inl.h"
 #include "src/arm64/frames-arm64.h"
 #include "src/base/bits.h"
 #include "src/base/cpu.h"
-#include "src/register-configuration.h"
 
 namespace v8 {
 namespace internal {
 
 
 // -----------------------------------------------------------------------------
 // CpuFeatures implementation.
 
 void CpuFeatures::ProbeImpl(bool cross_compile) {
   // AArch64 has no configuration options, no further probing is required.
@@ skipping 137 matching lines @@
 
 bool RelocInfo::IsInConstantPool() {
   Instruction* instr = reinterpret_cast<Instruction*>(pc_);
   return instr->IsLdrLiteralX();
 }
 
 
 Register GetAllocatableRegisterThatIsNotOneOf(Register reg1, Register reg2,
                                               Register reg3, Register reg4) {
   CPURegList regs(reg1, reg2, reg3, reg4);
-  const RegisterConfiguration* config = RegisterConfiguration::ArchDefault();
-  for (int i = 0; i < config->num_allocatable_double_registers(); ++i) {
-    int code = config->GetAllocatableDoubleCode(i);
-    Register candidate = Register::from_code(code);
+  for (int i = 0; i < Register::NumAllocatableRegisters(); i++) {
+    Register candidate = Register::FromAllocationIndex(i);
     if (regs.IncludesAliasOf(candidate)) continue;
     return candidate;
   }
   UNREACHABLE();
   return NoReg;
 }
 
 
 bool AreAliased(const CPURegister& reg1, const CPURegister& reg2,
                 const CPURegister& reg3, const CPURegister& reg4,
@@ skipping 2932 matching lines @@
   movk(scratch, (target_offset >> 32) & 0xFFFF, 32);
   DCHECK((target_offset >> 48) == 0);
   add(rd, rd, scratch);
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_ARM64