Fix deoptimization address patching in Turbofan to use safepoints.

src/objects-inl.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.
 //
 // Review notes:
 //
 // - The use of macros in these inline functions may seem superfluous
 // but it is absolutely needed to make sure gcc generates optimal
 // code. gcc is not happy when attempting to inline too deep.
 //
@@ skipping 699 matching lines @@
 bool Object::IsDeoptimizationInputData() const {
   // Must be a fixed array.
   if (!IsFixedArray()) return false;
 
   // There's no sure way to detect the difference between a fixed array and
   // a deoptimization data array.  Since this is used for asserts we can
   // check that the length is zero or else the fixed size plus a multiple of
   // the entry size.
   int length = FixedArray::cast(this)->length();
   if (length == 0) return true;
-  if (length < DeoptimizationInputData::kFirstDeoptEntryIndex) return false;
 
-  FixedArray* self = FixedArray::cast(const_cast<Object*>(this));
-  int deopt_count =
-      Smi::cast(self->get(DeoptimizationInputData::kDeoptEntryCountIndex))
-          ->value();
-  int patch_count =
-      Smi::cast(
-          self->get(
-              DeoptimizationInputData::kReturnAddressPatchEntryCountIndex))
-          ->value();
-
-  return length == DeoptimizationInputData::LengthFor(deopt_count, patch_count);
+  length -= DeoptimizationInputData::kFirstDeoptEntryIndex;
+  return length >= 0 && length % DeoptimizationInputData::kDeoptEntrySize == 0;
 }
 
 
 bool Object::IsDeoptimizationOutputData() const {
   if (!IsFixedArray()) return false;
   // There's actually no way to see the difference between a fixed array and
   // a deoptimization data array.  Since this is used for asserts we can check
   // that the length is plausible though.
   if (FixedArray::cast(this)->length() % 2 != 0) return false;
   return true;
@@ skipping 6526 matching lines @@
 #undef READ_SHORT_FIELD
 #undef WRITE_SHORT_FIELD
 #undef READ_BYTE_FIELD
 #undef WRITE_BYTE_FIELD
 #undef NOBARRIER_READ_BYTE_FIELD
 #undef NOBARRIER_WRITE_BYTE_FIELD
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_INL_H_