PredictableCodeSizeScope checks the expected size now.

src/arm/lithium-codegen-arm.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 2529 matching lines @@
   Register map = temp;
   __ ldr(map, FieldMemOperand(object, HeapObject::kMapOffset));
   {
     // Block constant pool emission to ensure the positions of instructions are
     // as expected by the patcher. See InstanceofStub::Generate().
     Assembler::BlockConstPoolScope block_const_pool(masm());
     __ bind(deferred->map_check());  // Label for calculating code patching.
     // We use Factory::the_hole_value() on purpose instead of loading from the
     // root array to force relocation to be able to later patch with
     // the cached map.
-    PredictableCodeSizeScope predictable(masm_);
+    PredictableCodeSizeScope predictable(masm_, 5 * Assembler::kInstrSize);
     Handle<JSGlobalPropertyCell> cell =
         factory()->NewJSGlobalPropertyCell(factory()->the_hole_value());
     __ mov(ip, Operand(Handle<Object>(cell)));
     __ ldr(ip, FieldMemOperand(ip, JSGlobalPropertyCell::kValueOffset));
     __ cmp(map, Operand(ip));
     __ b(ne, &cache_miss);
     // We use Factory::the_hole_value() on purpose instead of loading from the
     // root array to force relocation to be able to later patch
     // with true or false.
     __ mov(result, Operand(factory()->the_hole_value()));
@@ skipping 43 matching lines @@
 
   // Get the temp register reserved by the instruction. This needs to be r4 as
   // its slot of the pushing of safepoint registers is used to communicate the
   // offset to the location of the map check.
   Register temp = ToRegister(instr->temp());
   ASSERT(temp.is(r4));
   __ LoadHeapObject(InstanceofStub::right(), instr->function());
   static const int kAdditionalDelta = 5;
   // Make sure that code size is predicable, since we use specific constants
   // offsets in the code to find embedded values..
-  PredictableCodeSizeScope predictable(masm_);
+  PredictableCodeSizeScope predictable(masm_, 6 * Assembler::kInstrSize);
   int delta = masm_->InstructionsGeneratedSince(map_check) + kAdditionalDelta;
   Label before_push_delta;
   __ bind(&before_push_delta);
   __ BlockConstPoolFor(kAdditionalDelta);
   __ mov(temp, Operand(delta * kPointerSize));
   // The mov above can generate one or two instructions. The delta was computed
   // for two instructions, so we need to pad here in case of one instruction.
   if (masm_->InstructionsGeneratedSince(&before_push_delta) != 2) {
     ASSERT_EQ(1, masm_->InstructionsGeneratedSince(&before_push_delta));
     __ nop();
@@ skipping 3008 matching lines @@
   LEnvironment* env = instr->environment();
   // There is no LLazyBailout instruction for stack-checks. We have to
   // prepare for lazy deoptimization explicitly here.
   if (instr->hydrogen()->is_function_entry()) {
     // Perform stack overflow check.
     Label done;
     __ LoadRoot(ip, Heap::kStackLimitRootIndex);
     __ cmp(sp, Operand(ip));
     __ b(hs, &done);
     StackCheckStub stub;
-    PredictableCodeSizeScope predictable(masm_);
+    PredictableCodeSizeScope predictable(masm_, 2 * Assembler::kInstrSize);
     CallCode(stub.GetCode(), RelocInfo::CODE_TARGET, instr);
     EnsureSpaceForLazyDeopt();
     __ bind(&done);
     RegisterEnvironmentForDeoptimization(env, Safepoint::kLazyDeopt);
     safepoints_.RecordLazyDeoptimizationIndex(env->deoptimization_index());
   } else {
     ASSERT(instr->hydrogen()->is_backwards_branch());
     // Perform stack overflow check if this goto needs it before jumping.
     DeferredStackCheck* deferred_stack_check =
         new(zone()) DeferredStackCheck(this, instr);
@@ skipping 118 matching lines @@
   __ sub(scratch, result, Operand(index, LSL, kPointerSizeLog2 - kSmiTagSize));
   __ ldr(result, FieldMemOperand(scratch,
                                  FixedArray::kHeaderSize - kPointerSize));
   __ bind(&done);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal