PPC: Fix constant pool overflow access in Get/SetRelocatedValue.

src/ppc/macro-assembler-ppc.h

 // 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.
 
 #ifndef V8_PPC_MACRO_ASSEMBLER_PPC_H_
 #define V8_PPC_MACRO_ASSEMBLER_PPC_H_
 
 #include "src/assembler.h"
 #include "src/bailout-reason.h"
 #include "src/frames.h"
@@ skipping 1349 matching lines @@
                                                 Label* failure);
 
   void JumpIfNotUniqueNameInstanceType(Register reg, Label* not_unique_name);
 
   void EmitSeqStringSetCharCheck(Register string, Register index,
                                  Register value, uint32_t encoding_mask);
 
   // ---------------------------------------------------------------------------
   // Patching helpers.
 
+  // Decode offset from constant pool load instruction(s).
+  // Caller must place the instruction word at <location> in <result>.
+  void DecodeConstantPoolOffset(Register result, Register location);
+
   // Retrieve/patch the relocated value (lis/ori pair or constant pool load).
   void GetRelocatedValue(Register location, Register result, Register scratch);
   void SetRelocatedValue(Register location, Register scratch,
                          Register new_value);
 
   void ClampUint8(Register output_reg, Register input_reg);
 
   // Saturate a value into 8-bit unsigned integer
   //   if input_value < 0, output_value is 0
   //   if input_value > 255, output_value is 255
@@ skipping 189 matching lines @@
 #define ACCESS_MASM(masm)    \
   masm->stop(__FILE_LINE__); \
   masm->
 #else
 #define ACCESS_MASM(masm) masm->
 #endif
 }
 }  // namespace v8::internal
 
 #endif  // V8_PPC_MACRO_ASSEMBLER_PPC_H_