Check for empty repetitions.

src/regexp-macro-assembler-ia32.cc

Index: src/regexp-macro-assembler-ia32.cc
diff --git a/src/regexp-macro-assembler-ia32.cc b/src/regexp-macro-assembler-ia32.cc
index 89b416ce51e9baf3d60217438e5df9c25c81f899..d743268b99a57e92d57aec9f1a19c80582ed1b81 100644
--- a/src/regexp-macro-assembler-ia32.cc
+++ b/src/regexp-macro-assembler-ia32.cc
@@ -744,6 +744,13 @@ void RegExpMacroAssemblerIA32::IfRegisterLT(int reg,
 }
 
 
+void RegExpMacroAssemblerIA32::IfRegisterEqPos(int reg,
+                                               Label* if_eq) {
+  __ cmp(edi, register_location(reg));
+  BranchOrBacktrack(equal, if_eq);
+}
+
+
 RegExpMacroAssembler::IrregexpImplementation
     RegExpMacroAssemblerIA32::Implementation() {
   return kIA32Implementation;