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

src/arm/macro-assembler-arm.h

 // 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.
 
 #ifndef V8_ARM_MACRO_ASSEMBLER_ARM_H_
 #define V8_ARM_MACRO_ASSEMBLER_ARM_H_
 
 #include "src/assembler.h"
 #include "src/bailout-reason.h"
 #include "src/frames.h"
@@ skipping 745 matching lines @@
   // tag_allocated_object is true the result is tagged as as a heap object.
   // All registers are clobbered also when control continues at the gc_required
   // label.
   void Allocate(int object_size,
                 Register result,
                 Register scratch1,
                 Register scratch2,
                 Label* gc_required,
                 AllocationFlags flags);
 
-  void Allocate(Register object_size,
-                Register result,
-                Register scratch1,
-                Register scratch2,
-                Label* gc_required,
-                AllocationFlags flags);
+  void Allocate(Register object_size, Register result, Register result_end,
+                Register scratch, Label* gc_required, AllocationFlags flags);
 
   void AllocateTwoByteString(Register result,
                              Register length,
                              Register scratch1,
                              Register scratch2,
                              Register scratch3,
                              Label* gc_required);
   void AllocateOneByteString(Register result, Register length,
                              Register scratch1, Register scratch2,
                              Register scratch3, Label* gc_required);
@@ skipping 38 matching lines @@
                   int field_count);
 
   // Copies a number of bytes from src to dst. All registers are clobbered. On
   // exit src and dst will point to the place just after where the last byte was
   // read or written and length will be zero.
   void CopyBytes(Register src,
                  Register dst,
                  Register length,
                  Register scratch);
 
-  // Initialize fields with filler values.  Fields starting at |start_offset|
-  // not including end_offset are overwritten with the value in |filler|.  At
-  // the end the loop, |start_offset| takes the value of |end_offset|.
-  void InitializeFieldsWithFiller(Register start_offset,
-                                  Register end_offset,
-                                  Register filler);
+  // Initialize fields with filler values.  Fields starting at |current_address|
+  // not including |end_address| are overwritten with the value in |filler|.  At
+  // the end the loop, |current_address| takes the value of |end_address|.
+  void InitializeFieldsWithFiller(Register current_address,
+                                  Register end_address, Register filler);
 
   // ---------------------------------------------------------------------------
   // Support functions.
 
   // Machine code version of Map::GetConstructor().
   // |temp| holds |result|'s map when done, and |temp2| its instance type.
   void GetMapConstructor(Register result, Register map, Register temp,
                          Register temp2);
 
   // Try to get function prototype of a function and puts the value in
@@ skipping 716 matching lines @@
 #define ACCESS_MASM(masm) masm->stop(__FILE_LINE__); masm->
 #else
 #define ACCESS_MASM(masm) masm->
 #endif
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_ARM_MACRO_ASSEMBLER_ARM_H_