Thumb2 Backend: Update Code objects with mode, separate Assembler methods for Thumb2

src/arm/assembler-thumb.cc

 // Copyright 2013 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 1332 matching lines @@
   emit32(thumb32_mode3(MOVT_32_IMM) |
          thumb32_1reg_zero_extend_imm_split_4i38(reg, immediate));
 }
 
 
 void Assembler::ldr_pc_thumb(Register dst, const Operand& src) {
   RecordRelocInfo(src.rmode_, src.imm32_, USE_CONSTANT_POOL);
   ldr_thumb(dst, MemOperand(pc, 0));
 }
 
+
+bool Assembler::IsThumbLdrPcImmediateOffset(Instr instr) {
+  // Check the instruction is indeed a
+  // ldr<cond> <Rd>, [pc +/- offset_12].
+  return (instr & kThumbLdrPCMask) == kThumbLdrPCPattern;
+}
+
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM