Regexp: Optimize better in presence of lookaround.

src/regexp/jsregexp.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/regexp/jsregexp.h"
 
 #include <memory>
 
 #include "src/base/platform/platform.h"
 #include "src/compilation-cache.h"
@@ skipping 2284 matching lines @@
   if (budget <= 0) return 0;
   if (action_type_ == POSITIVE_SUBMATCH_SUCCESS) return 0;  // Rewinds input!
   return on_success()->EatsAtLeast(still_to_find,
                                    budget - 1,
                                    not_at_start);
 }
 
 
 void ActionNode::FillInBMInfo(Isolate* isolate, int offset, int budget,
                               BoyerMooreLookahead* bm, bool not_at_start) {
-  if (action_type_ == BEGIN_SUBMATCH) {
-    bm->SetRest(offset);
-  } else if (action_type_ != POSITIVE_SUBMATCH_SUCCESS) {
+  if (action_type_ != POSITIVE_SUBMATCH_SUCCESS) {
     on_success()->FillInBMInfo(isolate, offset, budget - 1, bm, not_at_start);
   }
   SaveBMInfo(bm, not_at_start, offset);
 }
 
 
 int AssertionNode::EatsAtLeast(int still_to_find,
                                int budget,
                                bool not_at_start) {
   if (budget <= 0) return 0;
@@ skipping 4606 matching lines @@
 
 
 void RegExpResultsCache::Clear(FixedArray* cache) {
   for (int i = 0; i < kRegExpResultsCacheSize; i++) {
     cache->set(i, Smi::kZero);
   }
 }
 
 }  // namespace internal
 }  // namespace v8