Port irregexp bytecode compiler and interpreter from V8 r24065.

runtime/vm/intrinsifier_mips.cc

Index: runtime/vm/intrinsifier_mips.cc
diff --git a/runtime/vm/intrinsifier_mips.cc b/runtime/vm/intrinsifier_mips.cc
index ecf07e6b536ec97f1de3fdaab08c6f67f5b25985..09bc9777713225fdaffbb2c9ec414657c67fb267 100644
--- a/runtime/vm/intrinsifier_mips.cc
+++ b/runtime/vm/intrinsifier_mips.cc
@@ -17,6 +17,8 @@
 
 namespace dart {
 
+DECLARE_FLAG(bool, interpret_irregexp);
+
 // When entering intrinsics code:
 // S5: IC Data
 // S4: Arguments descriptor
@@ -2075,6 +2077,8 @@ void Intrinsifier::TwoByteString_equality(Assembler* assembler) {
 
 
 void Intrinsifier::JSRegExp_ExecuteMatch(Assembler* assembler) {
+  if (FLAG_interpret_irregexp) return;
+
   static const intptr_t kRegExpParamOffset = 2 * kWordSize;
   static const intptr_t kStringParamOffset = 1 * kWordSize;
   // start_index smi is located at 0.