Make BitField3 a raw uint32 field, and move to the start of the map.

src/arm64/macro-assembler-arm64.cc

 // 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.
 
 #include "v8.h"
 
 #if V8_TARGET_ARCH_ARM64
 
 #include "bootstrapper.h"
 #include "codegen.h"
@@ skipping 1311 matching lines @@
 
 
 void MacroAssembler::NumberOfOwnDescriptors(Register dst, Register map) {
   Ldr(dst, FieldMemOperand(map, Map::kBitField3Offset));
   DecodeField<Map::NumberOfOwnDescriptorsBits>(dst);
 }
 
 
 void MacroAssembler::EnumLengthUntagged(Register dst, Register map) {
   STATIC_ASSERT(Map::EnumLengthBits::kShift == 0);
-  Ldrsw(dst, UntagSmiFieldMemOperand(map, Map::kBitField3Offset));
+  Ldrsw(dst, FieldMemOperand(map, Map::kBitField3Offset));
   And(dst, dst, Map::EnumLengthBits::kMask);
 }
 
 
 void MacroAssembler::EnumLengthSmi(Register dst, Register map) {
-  STATIC_ASSERT(Map::EnumLengthBits::kShift == 0);
-  Ldr(dst, FieldMemOperand(map, Map::kBitField3Offset));
-  And(dst, dst, Smi::FromInt(Map::EnumLengthBits::kMask));
+  EnumLengthUntagged(dst, map);
+  SmiTag(dst, dst);
 }
 
 
 void MacroAssembler::CheckEnumCache(Register object,
                                     Register null_value,
                                     Register scratch0,
                                     Register scratch1,
                                     Register scratch2,
                                     Register scratch3,
                                     Label* call_runtime) {
@@ skipping 3161 matching lines @@
 
   // Fall through if it does not have the right color.
 }
 
 
 void MacroAssembler::CheckMapDeprecated(Handle<Map> map,
                                         Register scratch,
                                         Label* if_deprecated) {
   if (map->CanBeDeprecated()) {
     Mov(scratch, Operand(map));
-    Ldrsw(scratch, UntagSmiFieldMemOperand(scratch, Map::kBitField3Offset));
+    Ldrsw(scratch, FieldMemOperand(scratch, Map::kBitField3Offset));
     TestAndBranchIfAnySet(scratch, Map::Deprecated::kMask, if_deprecated);
   }
 }
 
 
 void MacroAssembler::JumpIfBlack(Register object,
                                  Register scratch0,
                                  Register scratch1,
                                  Label* on_black) {
   ASSERT(strcmp(Marking::kBlackBitPattern, "10") == 0);
@@ skipping 702 matching lines @@
   }
 }
 
 
 #undef __
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM64