Use Copy-on-write arrays for cached regexp results.

src/ia32/full-codegen-ia32.cc

Index: src/ia32/full-codegen-ia32.cc
diff --git a/src/ia32/full-codegen-ia32.cc b/src/ia32/full-codegen-ia32.cc
index 68a0a960f9e92266a1b1f3512805bfb682fd7901..684ee14dd1a45d94574fd7633aa8bc458175380f 100644
--- a/src/ia32/full-codegen-ia32.cc
+++ b/src/ia32/full-codegen-ia32.cc
@@ -2640,6 +2640,14 @@ void FullCodeGenerator::EmitRegExpConstructResult(ZoneList<Expression*>* args) {
 }
 
 
+void FullCodeGenerator::EmitRegExpCloneResult(ZoneList<Expression*>* args) {
+  ASSERT(args->length() == 1);
+  VisitForValue(args->at(0), kStack);
+  __ CallRuntime(Runtime::kRegExpCloneResult, 1);
+  Apply(context_, eax);
+}
+
+
 void FullCodeGenerator::EmitSwapElements(ZoneList<Expression*>* args) {
   ASSERT(args->length() == 3);
   VisitForValue(args->at(0), kStack);