* Move irregexp backtrack stack to external memory area, instead of the system stack.

src/regexp-macro-assembler-irregexp.h

Index: src/regexp-macro-assembler-irregexp.h
diff --git a/src/regexp-macro-assembler-irregexp.h b/src/regexp-macro-assembler-irregexp.h
index 1167b1d53162c3feafe3974f55c0ff23a2cf361d..1fde6fda1a872a13dc8ca4d939994bd493f298c1 100644
--- a/src/regexp-macro-assembler-irregexp.h
+++ b/src/regexp-macro-assembler-irregexp.h
@@ -48,18 +48,21 @@ class RegExpMacroAssemblerIrregexp: public RegExpMacroAssembler {
   // upon destruction of the assembler.
   explicit RegExpMacroAssemblerIrregexp(Vector<byte>);
   virtual ~RegExpMacroAssemblerIrregexp();
+  // The byte-code interpreter checks on each push anyway.
+  virtual int stack_limit() { return 1; }
   virtual void Bind(Label* label);
   virtual void EmitOrLink(Label* label);
   virtual void AdvanceCurrentPosition(int by);  // Signed cp change.
   virtual void PopCurrentPosition();
-  virtual void PushCurrentPosition();
+  virtual void PushCurrentPosition(StackCheckFlag check_stack_limit);
   virtual void Backtrack();
   virtual void GoTo(Label* label);
-  virtual void PushBacktrack(Label* label);
+  virtual void PushBacktrack(Label* label, StackCheckFlag check_stack_limit);
   virtual void Succeed();
   virtual void Fail();
   virtual void PopRegister(int register_index);
-  virtual void PushRegister(int register_index);
+  virtual void PushRegister(int register_index,
+                            StackCheckFlag check_stack_limit);
   virtual void AdvanceRegister(int reg, int by);  // r[reg] += by.
   virtual void SetRegister(int register_index, int to);
   virtual void WriteCurrentPositionToRegister(int reg, int cp_offset);