RegExp: remove last match info override.

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 "src/ast.h"
 #include "src/base/platform/platform.h"
 #include "src/compilation-cache.h"
 #include "src/compiler.h"
@@ skipping 6392 matching lines @@
   if (heap->total_regexp_code_generated() > RegExpImpl::kRegExpCompiledLimit &&
       heap->isolate()->memory_allocator()->SizeExecutable() >
           RegExpImpl::kRegExpExecutableMemoryLimit) {
     too_much = true;
   }
   return too_much;
 }
 
 
 Object* RegExpResultsCache::Lookup(Heap* heap, String* key_string,
-                                   Object* key_pattern, ResultsCacheType type) {
+                                   Object* key_pattern,
+                                   FixedArray** last_match_cache,
+                                   ResultsCacheType type) {
   FixedArray* cache;
   if (!key_string->IsInternalizedString()) return Smi::FromInt(0);
   if (type == STRING_SPLIT_SUBSTRINGS) {
     DCHECK(key_pattern->IsString());
     if (!key_pattern->IsInternalizedString()) return Smi::FromInt(0);
     cache = heap->string_split_cache();
   } else {
     DCHECK(type == REGEXP_MULTIPLE_INDICES);
     DCHECK(key_pattern->IsFixedArray());
     cache = heap->regexp_multiple_cache();
   }
 
   uint32_t hash = key_string->Hash();
   uint32_t index = ((hash & (kRegExpResultsCacheSize - 1)) &
                     ~(kArrayEntriesPerCacheEntry - 1));
-  if (cache->get(index + kStringOffset) == key_string &&
-      cache->get(index + kPatternOffset) == key_pattern) {
-    return cache->get(index + kArrayOffset);
+  if (cache->get(index + kStringOffset) != key_string ||
+      cache->get(index + kPatternOffset) != key_pattern) {
+    index =
+        ((index + kArrayEntriesPerCacheEntry) & (kRegExpResultsCacheSize - 1));
+    if (cache->get(index + kStringOffset) != key_string ||
+        cache->get(index + kPatternOffset) != key_pattern) {
+      return Smi::FromInt(0);
+    }
   }
-  index =
-      ((index + kArrayEntriesPerCacheEntry) & (kRegExpResultsCacheSize - 1));
-  if (cache->get(index + kStringOffset) == key_string &&
-      cache->get(index + kPatternOffset) == key_pattern) {
-    return cache->get(index + kArrayOffset);
-  }
-  return Smi::FromInt(0);
+
+  *last_match_cache = FixedArray::cast(cache->get(index + kLastMatchOffset));
+  return cache->get(index + kArrayOffset);
 }
 
 
 void RegExpResultsCache::Enter(Isolate* isolate, Handle<String> key_string,
                                Handle<Object> key_pattern,
                                Handle<FixedArray> value_array,
+                               Handle<FixedArray> last_match_cache,
                                ResultsCacheType type) {
   Factory* factory = isolate->factory();
   Handle<FixedArray> cache;
   if (!key_string->IsInternalizedString()) return;
   if (type == STRING_SPLIT_SUBSTRINGS) {
     DCHECK(key_pattern->IsString());
     if (!key_pattern->IsInternalizedString()) return;
     cache = factory->string_split_cache();
   } else {
     DCHECK(type == REGEXP_MULTIPLE_INDICES);
     DCHECK(key_pattern->IsFixedArray());
     cache = factory->regexp_multiple_cache();
   }
 
   uint32_t hash = key_string->Hash();
   uint32_t index = ((hash & (kRegExpResultsCacheSize - 1)) &
                     ~(kArrayEntriesPerCacheEntry - 1));
   if (cache->get(index + kStringOffset) == Smi::FromInt(0)) {
     cache->set(index + kStringOffset, *key_string);
     cache->set(index + kPatternOffset, *key_pattern);
     cache->set(index + kArrayOffset, *value_array);
+    cache->set(index + kLastMatchOffset, *last_match_cache);
   } else {
     uint32_t index2 =
         ((index + kArrayEntriesPerCacheEntry) & (kRegExpResultsCacheSize - 1));
     if (cache->get(index2 + kStringOffset) == Smi::FromInt(0)) {
       cache->set(index2 + kStringOffset, *key_string);
       cache->set(index2 + kPatternOffset, *key_pattern);
       cache->set(index2 + kArrayOffset, *value_array);
+      cache->set(index2 + kLastMatchOffset, *last_match_cache);
     } else {
       cache->set(index2 + kStringOffset, Smi::FromInt(0));
       cache->set(index2 + kPatternOffset, Smi::FromInt(0));
       cache->set(index2 + kArrayOffset, Smi::FromInt(0));
+      cache->set(index2 + kLastMatchOffset, Smi::FromInt(0));
       cache->set(index + kStringOffset, *key_string);
       cache->set(index + kPatternOffset, *key_pattern);
       cache->set(index + kArrayOffset, *value_array);
+      cache->set(index + kLastMatchOffset, *last_match_cache);
     }
   }
   // If the array is a reasonably short list of substrings, convert it into a
   // list of internalized strings.
   if (type == STRING_SPLIT_SUBSTRINGS && value_array->length() < 100) {
     for (int i = 0; i < value_array->length(); i++) {
       Handle<String> str(String::cast(value_array->get(i)), isolate);
       Handle<String> internalized_str = factory->InternalizeString(str);
       value_array->set(i, *internalized_str);
     }
   }
   // Convert backing store to a copy-on-write array.
   value_array->set_map_no_write_barrier(*factory->fixed_cow_array_map());
 }
 
 
 void RegExpResultsCache::Clear(FixedArray* cache) {
   for (int i = 0; i < kRegExpResultsCacheSize; i++) {
     cache->set(i, Smi::FromInt(0));
   }
 }
 
 }  // namespace internal
 }  // namespace v8