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

runtime/vm/intrinsifier_arm64.cc

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"  // Needed here to get TARGET_ARCH_ARM64.
 #if defined(TARGET_ARCH_ARM64)
 
 #include "vm/intrinsifier.h"
 
 #include "vm/assembler.h"
@@ skipping 2266 matching lines @@
 void Intrinsifier::OneByteString_equality(Assembler* assembler) {
   StringEquality(assembler, kOneByteStringCid);
 }
 
 
 void Intrinsifier::TwoByteString_equality(Assembler* assembler) {
   StringEquality(assembler, kTwoByteStringCid);
 }
 
 
-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;
   static const intptr_t kStringParamOffset = 1 * kWordSize;
   // start_index smi is located at offset 0.
 
   // Incoming registers:
   // R0: Function. (Will be reloaded with the specialized matcher function.)
   // R4: Arguments descriptor. (Will be preserved.)
   // R5: Unknown. (Must be GC safe on tail call.)
 
   // Load the specialized function pointer into R0. Leverage the fact the
   // string CIDs as well as stored function pointers are in sequence.
   __ ldr(R2, Address(SP, kRegExpParamOffset));
   __ ldr(R1, Address(SP, kStringParamOffset));
   __ 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 R5.
   __ eor(R5, R5, Operand(R5));
 
   // Tail-call the function.
   __ ldr(CODE_REG, FieldAddress(R0, Function::code_offset()));
   __ ldr(R1, FieldAddress(R0, Function::entry_point_offset()));
   __ br(R1);
 }
@@ skipping 44 matching lines @@
   __ cmp(R0, Operand(0));
   __ LoadObject(R0, Bool::False());
   __ LoadObject(TMP, Bool::True());
   __ csel(R0, TMP, R0, NE);
   __ ret();
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_ARM64