Change the handling of stack check on backward branches

src/x64/lithium-x64.h

 // Copyright 2011 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 356 matching lines @@
 class LInstructionGap: public LGap {
  public:
   explicit LInstructionGap(HBasicBlock* block) : LGap(block) { }
 
   DECLARE_CONCRETE_INSTRUCTION(InstructionGap, "gap")
 };
 
 
 class LGoto: public LTemplateInstruction<0, 0, 0> {
  public:
-  LGoto(int block_id, bool include_stack_check = false)
-    : block_id_(block_id), include_stack_check_(include_stack_check) { }
+  explicit LGoto(int block_id) : block_id_(block_id) { }
 
   DECLARE_CONCRETE_INSTRUCTION(Goto, "goto")
   virtual void PrintDataTo(StringStream* stream);
   virtual bool IsControl() const { return true; }
 
   int block_id() const { return block_id_; }
-  bool include_stack_check() const { return include_stack_check_; }
 
  private:
   int block_id_;
-  bool include_stack_check_;
 };
 
 
 class LLazyBailout: public LTemplateInstruction<0, 0, 0> {
  public:
   LLazyBailout() : gap_instructions_size_(0) { }
 
   DECLARE_CONCRETE_INSTRUCTION(LazyBailout, "lazy-bailout")
 
   void set_gap_instructions_size(int gap_instructions_size) {
@@ skipping 1680 matching lines @@
   // NULL if the register has no assigned spill slot.  Indexed by allocation
   // index.
   LOperand* register_spills_[Register::kNumAllocatableRegisters];
   LOperand* double_register_spills_[DoubleRegister::kNumAllocatableRegisters];
 };
 
 
 class LStackCheck: public LTemplateInstruction<0, 0, 0> {
  public:
   DECLARE_CONCRETE_INSTRUCTION(StackCheck, "stack-check")
+  DECLARE_HYDROGEN_ACCESSOR(StackCheck)
+
+  Label* done_label() { return &done_label_; }
+
+ private:
+  Label done_label_;
 };
 
 
 class LChunkBuilder;
 class LChunk: public ZoneObject {
  public:
   explicit LChunk(CompilationInfo* info, HGraph* graph)
     : spill_slot_count_(0),
       info_(info),
       graph_(graph),
@@ skipping 211 matching lines @@
 
   DISALLOW_COPY_AND_ASSIGN(LChunkBuilder);
 };
 
 #undef DECLARE_HYDROGEN_ACCESSOR
 #undef DECLARE_CONCRETE_INSTRUCTION
 
 } }  // namespace v8::int
 
 #endif  // V8_X64_LITHIUM_X64_H_