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

src/mips64/macro-assembler-mips64.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 <limits.h>  // For LONG_MIN, LONG_MAX.
 
 #if V8_TARGET_ARCH_MIPS64
 
 #include "src/base/division-by-constant.h"
 #include "src/bootstrapper.h"
@@ skipping 3516 matching lines @@
   Branch(gc_required, Ugreater, scratch2, Operand(t9));
   sd(scratch2, MemOperand(topaddr));
 
   // Tag object if requested.
   if ((flags & TAG_OBJECT) != 0) {
     Daddu(result, result, Operand(kHeapObjectTag));
   }
 }
 
 
-void MacroAssembler::Allocate(Register object_size,
-                              Register result,
-                              Register scratch1,
-                              Register scratch2,
-                              Label* gc_required,
-                              AllocationFlags flags) {
+void MacroAssembler::Allocate(Register object_size, Register result,
+                              Register result_end, Register scratch,
+                              Label* gc_required, AllocationFlags flags) {
   if (!FLAG_inline_new) {
     if (emit_debug_code()) {
       // Trash the registers to simulate an allocation failure.
       li(result, 0x7091);
-      li(scratch1, 0x7191);
-      li(scratch2, 0x7291);
+      li(scratch, 0x7191);
+      li(result_end, 0x7291);
     }
     jmp(gc_required);
     return;
   }
 
-  DCHECK(!result.is(scratch1));
-  DCHECK(!result.is(scratch2));
-  DCHECK(!scratch1.is(scratch2));
+  DCHECK(!result.is(scratch));
+  DCHECK(!result.is(result_end));
+  DCHECK(!scratch.is(result_end));
   DCHECK(!object_size.is(t9));
-  DCHECK(!scratch1.is(t9) && !scratch2.is(t9) && !result.is(t9));
+  DCHECK(!scratch.is(t9) && !result_end.is(t9) && !result.is(t9));
 
   // Check relative positions of allocation top and limit addresses.
   // ARM adds additional checks to make sure the ldm instruction can be
   // used. On MIPS we don't have ldm so we don't need additional checks either.
   ExternalReference allocation_top =
       AllocationUtils::GetAllocationTopReference(isolate(), flags);
   ExternalReference allocation_limit =
       AllocationUtils::GetAllocationLimitReference(isolate(), flags);
   intptr_t top   =
       reinterpret_cast<intptr_t>(allocation_top.address());
   intptr_t limit =
       reinterpret_cast<intptr_t>(allocation_limit.address());
   DCHECK((limit - top) == kPointerSize);
 
   // Set up allocation top address and object size registers.
-  Register topaddr = scratch1;
+  Register topaddr = scratch;
   li(topaddr, Operand(allocation_top));
 
   // This code stores a temporary value in t9.
   if ((flags & RESULT_CONTAINS_TOP) == 0) {
     // Load allocation top into result and allocation limit into t9.
     ld(result, MemOperand(topaddr));
     ld(t9, MemOperand(topaddr, kPointerSize));
   } else {
     if (emit_debug_code()) {
       // Assert that result actually contains top on entry. t9 is used
       // immediately below so this use of t9 does not cause difference with
       // respect to register content between debug and release mode.
       ld(t9, MemOperand(topaddr));
       Check(eq, kUnexpectedAllocationTop, result, Operand(t9));
     }
     // Load allocation limit into t9. Result already contains allocation top.
     ld(t9, MemOperand(topaddr, static_cast<int32_t>(limit - top)));
   }
 
   DCHECK(kPointerSize == kDoubleSize);
   if (emit_debug_code()) {
     And(at, result, Operand(kDoubleAlignmentMask));
     Check(eq, kAllocationIsNotDoubleAligned, at, Operand(zero_reg));
   }
 
   // Calculate new top and bail out if new space is exhausted. Use result
   // to calculate the new top. Object size may be in words so a shift is
   // required to get the number of bytes.
   if ((flags & SIZE_IN_WORDS) != 0) {
-    dsll(scratch2, object_size, kPointerSizeLog2);
-    Daddu(scratch2, result, scratch2);
+    dsll(result_end, object_size, kPointerSizeLog2);
+    Daddu(result_end, result, result_end);
   } else {
-    Daddu(scratch2, result, Operand(object_size));
+    Daddu(result_end, result, Operand(object_size));
   }
-  Branch(gc_required, Ugreater, scratch2, Operand(t9));
+  Branch(gc_required, Ugreater, result_end, Operand(t9));
 
   // Update allocation top. result temporarily holds the new top.
   if (emit_debug_code()) {
-    And(t9, scratch2, Operand(kObjectAlignmentMask));
+    And(t9, result_end, Operand(kObjectAlignmentMask));
     Check(eq, kUnalignedAllocationInNewSpace, t9, Operand(zero_reg));
   }
-  sd(scratch2, MemOperand(topaddr));
+  sd(result_end, MemOperand(topaddr));
 
   // Tag object if requested.
   if ((flags & TAG_OBJECT) != 0) {
     Daddu(result, result, Operand(kHeapObjectTag));
   }
 }
 
 
 void MacroAssembler::AllocateTwoByteString(Register result,
                                            Register length,
@@ skipping 265 matching lines @@
   lbu(scratch, MemOperand(src));
   Daddu(src, src, 1);
   sb(scratch, MemOperand(dst));
   Daddu(dst, dst, 1);
   Dsubu(length, length, Operand(1));
   Branch(&byte_loop_1, ne, length, Operand(zero_reg));
   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;
   Branch(&entry);
   bind(&loop);
-  sd(filler, MemOperand(start_offset));
-  Daddu(start_offset, start_offset, kPointerSize);
+  sd(filler, MemOperand(current_address));
+  Daddu(current_address, current_address, kPointerSize);
   bind(&entry);
-  Branch(&loop, ult, start_offset, Operand(end_offset));
+  Branch(&loop, ult, current_address, Operand(end_address));
 }
 
 
 void MacroAssembler::CheckFastElements(Register map,
                                        Register scratch,
                                        Label* fail) {
   STATIC_ASSERT(FAST_SMI_ELEMENTS == 0);
   STATIC_ASSERT(FAST_HOLEY_SMI_ELEMENTS == 1);
   STATIC_ASSERT(FAST_ELEMENTS == 2);
   STATIC_ASSERT(FAST_HOLEY_ELEMENTS == 3);
@@ skipping 2315 matching lines @@
   if (mag.shift > 0) sra(result, result, mag.shift);
   srl(at, dividend, 31);
   Addu(result, result, Operand(at));
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_MIPS64