Capture register clearing on loop iteration

src/regexp-macro-assembler-irregexp.cc

Index: src/regexp-macro-assembler-irregexp.cc
diff --git a/src/regexp-macro-assembler-irregexp.cc b/src/regexp-macro-assembler-irregexp.cc
index d962a739b268855c631e1c24be9b31d4ffc7ea36..a36f0a766dcfca61a5ffb06e0b4b54c2ed133fe8 100644
--- a/src/regexp-macro-assembler-irregexp.cc
+++ b/src/regexp-macro-assembler-irregexp.cc
@@ -107,6 +107,11 @@ void RegExpMacroAssemblerIrregexp::WriteCurrentPositionToRegister(
 }
 
 
+void RegExpMacroAssemblerIrregexp::ClearRegister(int reg) {
+  SetRegister(reg, -1);
+}
+
+
 void RegExpMacroAssemblerIrregexp::ReadCurrentPositionFromRegister(
     int register_index) {
   ASSERT(register_index >= 0);