Fix object initialization when slack tracking for it's map is still enabled.

src/ia32/macro-assembler-ia32.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.
 
 #if V8_TARGET_ARCH_IA32
 
 #include "src/base/bits.h"
 #include "src/base/division-by-constant.h"
 #include "src/bootstrapper.h"
 #include "src/codegen.h"
@@ skipping 1715 matching lines @@
   mov_b(Operand(destination, 0), scratch);
   inc(source);
   inc(destination);
   dec(length);
   j(not_zero, &short_loop);
 
   bind(&done);
 }
 
 
-void MacroAssembler::InitializeFieldsWithFiller(Register start_offset,
-                                                Register end_offset,
+void MacroAssembler::InitializeFieldsWithFiller(Register current_address,
+                                                Register end_address,
                                                 Register filler) {
   Label loop, entry;
   jmp(&entry);
   bind(&loop);
-  mov(Operand(start_offset, 0), filler);
-  add(start_offset, Immediate(kPointerSize));
+  mov(Operand(current_address, 0), filler);
+  add(current_address, Immediate(kPointerSize));
   bind(&entry);
-  cmp(start_offset, end_offset);
+  cmp(current_address, end_address);
   j(below, &loop);
 }
 
 
 void MacroAssembler::BooleanBitTest(Register object,
                                     int field_offset,
                                     int bit_index) {
   bit_index += kSmiTagSize + kSmiShiftSize;
   DCHECK(base::bits::IsPowerOfTwo32(kBitsPerByte));
   int byte_index = bit_index / kBitsPerByte;
@@ skipping 1391 matching lines @@
   mov(eax, dividend);
   shr(eax, 31);
   add(edx, eax);
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_IA32