Replace our home-grown BitCast with bit_cast from Chrome/Google3.

src/x64/assembler-x64.cc

 // Copyright 2012 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 "src/v8.h"
 
 #if V8_TARGET_ARCH_X64
 
 #include "src/base/bits.h"
 #include "src/macro-assembler.h"
@@ skipping 144 matching lines @@
   bool has_sib = ((modrm & 0x07) == 0x04);
   byte mode = modrm & 0xC0;
   int disp_offset = has_sib ? 2 : 1;
   int base_reg = (has_sib ? operand.buf_[1] : modrm) & 0x07;
   // Mode 0 with rbp/r13 as ModR/M or SIB base register always has a 32-bit
   // displacement.
   bool is_baseless = (mode == 0) && (base_reg == 0x05);  // No base or RIP base.
   int32_t disp_value = 0;
   if (mode == 0x80 || is_baseless) {
     // Mode 2 or mode 0 with rbp/r13 as base: Word displacement.
-    disp_value = *BitCast<const int32_t*>(&operand.buf_[disp_offset]);
+    disp_value = *bit_cast<const int32_t*>(&operand.buf_[disp_offset]);
   } else if (mode == 0x40) {
     // Mode 1: Byte displacement.
     disp_value = static_cast<signed char>(operand.buf_[disp_offset]);
   }
 
   // Write new operand with same registers, but with modified displacement.
   DCHECK(offset >= 0 ? disp_value + offset > disp_value
                      : disp_value + offset < disp_value);  // No overflow.
   disp_value += offset;
   rex_ = operand.rex_;
@@ skipping 2811 matching lines @@
 
 
 bool RelocInfo::IsInConstantPool() {
   return false;
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64