VM: Optimize RegExp.matchAsPrefix(...) by generating a sticky RegExp specialization.

runtime/vm/intrinsifier_arm.cc

Index: runtime/vm/intrinsifier_arm.cc
diff --git a/runtime/vm/intrinsifier_arm.cc b/runtime/vm/intrinsifier_arm.cc
index d79a9dada627d9c872d2c879797f246ce21bcc5c..99205a75eaa1c5a0a009c1da69194ccb725a5dc7 100644
--- a/runtime/vm/intrinsifier_arm.cc
+++ b/runtime/vm/intrinsifier_arm.cc
@@ -2218,7 +2218,8 @@ void Intrinsifier::TwoByteString_equality(Assembler* assembler) {
 }
 
 
-void Intrinsifier::RegExp_ExecuteMatch(Assembler* assembler) {
+void Intrinsifier::IntrinsifyRegExpExecuteMatch(Assembler* assembler,
+                                                bool sticky) {
   if (FLAG_interpret_irregexp) return;
 
   static const intptr_t kRegExpParamOffset = 2 * kWordSize;
@@ -2237,7 +2238,8 @@ void Intrinsifier::RegExp_ExecuteMatch(Assembler* assembler) {
   __ LoadClassId(R1, R1);
   __ AddImmediate(R1, R1, -kOneByteStringCid);
   __ add(R1, R2, Operand(R1, LSL, kWordSizeLog2));
-  __ ldr(R0, FieldAddress(R1, RegExp::function_offset(kOneByteStringCid)));
+  __ ldr(R0,
+         FieldAddress(R1, RegExp::function_offset(kOneByteStringCid, sticky)));
 
   // Registers are now set up for the lazy compile stub. It expects the function
   // in R0, the argument descriptor in R4, and IC-Data in R9.