PPC: [for-in] Sanitize for-in optimizations and fix bailout points.

src/ppc/macro-assembler-ppc.cc

 // Copyright 2014 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 <assert.h>  // For assert
 #include <limits.h>  // For LONG_MIN, LONG_MAX.
 
 #if V8_TARGET_ARCH_PPC
 
 #include "src/base/bits.h"
@@ skipping 3357 matching lines @@
   LoadInstanceDescriptors(dst, dst);
   LoadP(dst,
         FieldMemOperand(dst, DescriptorArray::GetValueOffset(accessor_index)));
   const int getterOffset = AccessorPair::kGetterOffset;
   const int setterOffset = AccessorPair::kSetterOffset;
   int offset = ((accessor == ACCESSOR_GETTER) ? getterOffset : setterOffset);
   LoadP(dst, FieldMemOperand(dst, offset));
 }
 
 
-void MacroAssembler::CheckEnumCache(Register null_value, Label* call_runtime) {
+void MacroAssembler::CheckEnumCache(Label* call_runtime) {
+  Register null_value = r8;
   Register empty_fixed_array_value = r9;
   LoadRoot(empty_fixed_array_value, Heap::kEmptyFixedArrayRootIndex);
   Label next, start;
   mr(r5, r3);
 
   // Check if the enum length field is properly initialized, indicating that
   // there is an enum cache.
   LoadP(r4, FieldMemOperand(r5, HeapObject::kMapOffset));
 
   EnumLength(r6, r4);
   CmpSmiLiteral(r6, Smi::FromInt(kInvalidEnumCacheSentinel), r0);
   beq(call_runtime);
 
+  LoadRoot(null_value, Heap::kNullValueRootIndex);
   b(&start);
 
   bind(&next);
   LoadP(r4, FieldMemOperand(r5, HeapObject::kMapOffset));
 
   // For all objects but the receiver, check that the cache is empty.
   EnumLength(r6, r4);
   CmpSmiLiteral(r6, Smi::FromInt(0), r0);
   bne(call_runtime);
 
@@ skipping 912 matching lines @@
   }
   if (mag.shift > 0) srawi(result, result, mag.shift);
   ExtractBit(r0, dividend, 31);
   add(result, result, r0);
 }
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_PPC