Make new space iterable when transitioning double array to objects

src/ia32/codegen-ia32.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 765 matching lines @@
 
 void ElementsTransitionGenerator::GenerateDoubleToObject(
     MacroAssembler* masm, AllocationSiteMode mode, Label* fail) {
   // ----------- S t a t e -------------
   //  -- eax    : value
   //  -- ebx    : target map
   //  -- ecx    : key
   //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
-  Label loop, entry, convert_hole, gc_required, only_change_map, success;
+  Label loop, entry, convert_hole, gc_required, gc_cleanup, only_change_map,
+      success;
 
   if (mode == TRACK_ALLOCATION_SITE) {
     __ JumpIfJSArrayHasAllocationMemento(edx, edi, fail);
   }
 
   // Check for empty arrays, which only require a map transition and no changes
   // to the backing store.
   __ mov(edi, FieldOperand(edx, JSObject::kElementsOffset));
   __ cmp(edi, Immediate(masm->isolate()->factory()->empty_fixed_array()));
   __ j(equal, &only_change_map);
@@ skipping 25 matching lines @@
   __ mov(FieldOperand(edx, HeapObject::kMapOffset), ebx);
   __ RecordWriteField(edx,
                       HeapObject::kMapOffset,
                       ebx,
                       edi,
                       kDontSaveFPRegs,
                       OMIT_REMEMBERED_SET,
                       OMIT_SMI_CHECK);
   __ jmp(&success);
 
+  __ bind(&gc_cleanup);
+#ifdef VERIFY_HEAP
+  // Make sure new space is iterable if we are verifying the heap.
+  __ mov(edx, Immediate(Smi::FromInt(0)));
+  __ mov(FieldOperand(eax, ebx, times_2, FixedArray::kHeaderSize), edx);
+  __ sub(ebx, Immediate(Smi::FromInt(1)));
+  __ j(not_sign, &gc_cleanup);
+#endif
+  __ bind(&gc_required);
   // Call into runtime if GC is required.
-  __ bind(&gc_required);
   __ mov(esi, Operand(ebp, StandardFrameConstants::kContextOffset));
   __ pop(ebx);
   __ pop(edx);
   __ pop(eax);
   __ jmp(fail);
 
   // Box doubles into heap numbers.
   // edi: source FixedDoubleArray
   // eax: destination FixedArray
   __ bind(&loop);
   // ebx: index of current element (smi-tagged)
   uint32_t offset = FixedDoubleArray::kHeaderSize + sizeof(kHoleNanLower32);
   __ cmp(FieldOperand(edi, ebx, times_4, offset), Immediate(kHoleNanUpper32));
   __ j(equal, &convert_hole);
 
   // Non-hole double, copy value into a heap number.
-  __ AllocateHeapNumber(edx, esi, no_reg, &gc_required);
+  __ AllocateHeapNumber(edx, esi, no_reg, &gc_cleanup);
   // edx: new heap number
   if (CpuFeatures::IsSupported(SSE2)) {
     CpuFeatureScope fscope(masm, SSE2);
     __ movsd(xmm0,
               FieldOperand(edi, ebx, times_4, FixedDoubleArray::kHeaderSize));
     __ movsd(FieldOperand(edx, HeapNumber::kValueOffset), xmm0);
   } else {
     __ mov(esi, FieldOperand(edi, ebx, times_4, FixedDoubleArray::kHeaderSize));
     __ mov(FieldOperand(edx, HeapNumber::kValueOffset), esi);
     __ mov(esi, FieldOperand(edi, ebx, times_4, offset));
@@ skipping 268 matching lines @@
     Code* stub = GetCodeAgeStub(isolate, age, parity);
     CodePatcher patcher(sequence, young_length);
     patcher.masm()->call(stub->instruction_start(), RelocInfo::NONE32);
   }
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32