Port irregexp bytecode compiler and interpreter from V8 r24065.

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"
 #include "vm/dart_entry.h"
 #include "vm/flow_graph_compiler.h"
 #include "vm/object.h"
 #include "vm/object_store.h"
 #include "vm/regexp_assembler.h"
 #include "vm/symbols.h"
 
 namespace dart {
 
+DECLARE_FLAG(bool, interpret_irregexp);
+
 // When entering intrinsics code:
 // R5: IC Data
 // R4: Arguments descriptor
 // LR: Return address
 // The R5, R4 registers can be destroyed only if there is no slow-path, i.e.
 // if the intrinsified method always executes a return.
 // The FP register should not be modified, because it is used by the profiler.
 
 #define __ assembler->
 
@@ skipping 2006 matching lines @@
   StringEquality(assembler, kOneByteStringCid);
 }
 
 
 void Intrinsifier::TwoByteString_equality(Assembler* assembler) {
   StringEquality(assembler, kTwoByteStringCid);
 }
 
 
 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 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
@@ skipping 53 matching lines @@
   Isolate* isolate = Isolate::Current();
   __ LoadImmediate(R1, reinterpret_cast<uword>(isolate), kNoPP);
   // Set return value to Isolate::current_tag_.
   __ ldr(R0, Address(R1, Isolate::current_tag_offset()));
   __ ret();
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_ARM64