Revert of Reland: Remove register index/code indirection

src/arm64/constants-arm64.h

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_ARM64_CONSTANTS_ARM64_H_
 #define V8_ARM64_CONSTANTS_ARM64_H_
 
 #include "src/base/macros.h"
 #include "src/globals.h"
 
@@ skipping 100 matching lines @@
 const unsigned kDoubleWordSizeInBytes = kDoubleWordSize >> 3;
 const unsigned kQuadWordSize = 128;
 const unsigned kQuadWordSizeInBytes = kQuadWordSize >> 3;
 // AArch64 floating-point specifics. These match IEEE-754.
 const unsigned kDoubleMantissaBits = 52;
 const unsigned kDoubleExponentBits = 11;
 const unsigned kDoubleExponentBias = 1023;
 const unsigned kFloatMantissaBits = 23;
 const unsigned kFloatExponentBits = 8;
 
+#define REGISTER_CODE_LIST(R)                                                  \
+R(0)  R(1)  R(2)  R(3)  R(4)  R(5)  R(6)  R(7)                                 \
+R(8)  R(9)  R(10) R(11) R(12) R(13) R(14) R(15)                                \
+R(16) R(17) R(18) R(19) R(20) R(21) R(22) R(23)                                \
+R(24) R(25) R(26) R(27) R(28) R(29) R(30) R(31)
+
 #define INSTRUCTION_FIELDS_LIST(V_)                                            \
 /* Register fields */                                                          \
 V_(Rd, 4, 0, Bits)                        /* Destination register.     */      \
 V_(Rn, 9, 5, Bits)                        /* First source register.    */      \
 V_(Rm, 20, 16, Bits)                      /* Second source register.   */      \
 V_(Ra, 14, 10, Bits)                      /* Third source register.    */      \
 V_(Rt, 4, 0, Bits)                        /* Load dest / store source. */      \
 V_(Rt2, 14, 10, Bits)                     /* Load second dest /        */      \
                                          /* store second source.      */       \
 V_(PrefetchMode, 4, 0, Bits)                                                   \
@@ skipping 1097 matching lines @@
 
 enum UnallocatedOp {
   UnallocatedFixed = 0x00000000,
   UnallocatedFMask = 0x00000000
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_ARM64_CONSTANTS_ARM64_H_