Maintain the invariant that the pattern string in an atom regexp is always ...

src/jsregexp.cc

 // Copyright 2006-2009 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 15 matching lines @@
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #include "v8.h"
 
 #include "ast.h"
 #include "compiler.h"
 #include "execution.h"
 #include "factory.h"
 #include "jsregexp.h"
 #include "platform.h"
+#include "string-search.h"
 #include "runtime.h"
 #include "top.h"
 #include "compilation-cache.h"
 #include "string-stream.h"
 #include "parser.h"
 #include "regexp-macro-assembler.h"
 #include "regexp-macro-assembler-tracer.h"
 #include "regexp-macro-assembler-irregexp.h"
 #include "regexp-stack.h"
 
@@ skipping 67 matching lines @@
   JSRegExp::Flags flags = RegExpFlagsFromString(flag_str);
   Handle<FixedArray> cached = CompilationCache::LookupRegExp(pattern, flags);
   bool in_cache = !cached.is_null();
   LOG(RegExpCompileEvent(re, in_cache));
 
   Handle<Object> result;
   if (in_cache) {
     re->set_data(*cached);
     return re;
   }
-  FlattenString(pattern);
+  pattern = FlattenGetString(pattern);
   CompilationZoneScope zone_scope(DELETE_ON_EXIT);
   PostponeInterruptsScope postpone;
   RegExpCompileData parse_result;
   FlatStringReader reader(pattern);
   if (!RegExpParser::ParseRegExp(&reader, flags.is_multiline(),
                                  &parse_result)) {
     // Throw an exception if we fail to parse the pattern.
     ThrowRegExpException(re,
                          pattern,
                          parse_result.error,
@@ skipping 64 matching lines @@
                                int from,
                                int to) {
   NoHandleAllocation no_handles;
   RegExpImpl::SetLastCaptureCount(array, 2);
   RegExpImpl::SetLastSubject(array, subject);
   RegExpImpl::SetLastInput(array, subject);
   RegExpImpl::SetCapture(array, 0, from);
   RegExpImpl::SetCapture(array, 1, to);
 }
 
+  /* template <typename SubjectChar>, typename PatternChar>
+static int ReStringMatch(Vector<const SubjectChar> sub_vector,
+                         Vector<const PatternChar> pat_vector,
+                         int start_index) {
 
+  int pattern_length = pat_vector.length();
+  if (pattern_length == 0) return start_index;
+
+  int subject_length = sub_vector.length();
+  if (start_index + pattern_length > subject_length) return -1;
+  return SearchString(sub_vector, pat_vector, start_index);
+}
+  */
 Handle<Object> RegExpImpl::AtomExec(Handle<JSRegExp> re,
                                     Handle<String> subject,
                                     int index,
                                     Handle<JSArray> last_match_info) {
-  Handle<String> needle(String::cast(re->DataAt(JSRegExp::kAtomPatternIndex)));
+  ASSERT(0 <= index);
+  ASSERT(index <= subject->length());
 
-  uint32_t start_index = index;
+  if (!subject->IsFlat()) FlattenString(subject);
+  AssertNoAllocation no_heap_allocation;  // ensure vectors stay valid
+  // Extract flattened substrings of cons strings before determining asciiness.
+  String* seq_sub = *subject;
+  if (seq_sub->IsConsString()) seq_sub = ConsString::cast(seq_sub)->first();
 
-  int value = Runtime::StringMatch(subject, needle, start_index);
-  if (value == -1) return Factory::null_value();
+  String* needle = String::cast(re->DataAt(JSRegExp::kAtomPatternIndex));
+  int needle_len = needle->length();
+
+  if (needle_len != 0) {
+    if (index + needle_len > subject->length()) return Factory::null_value();
+    // dispatch on type of strings
+    index = (needle->IsAsciiRepresentation()
+             ? (seq_sub->IsAsciiRepresentation()
+                ? SearchString(seq_sub->ToAsciiVector(),
+                               needle->ToAsciiVector(),
+                               index)
+                : SearchString(seq_sub->ToUC16Vector(),
+                               needle->ToAsciiVector(),
+                               index))
+             : (seq_sub->IsAsciiRepresentation()
+                ? SearchString(seq_sub->ToAsciiVector(),
+                               needle->ToUC16Vector(),
+                               index)
+                : SearchString(seq_sub->ToUC16Vector(),
+                               needle->ToUC16Vector(),
+                               index)));
+    if (index == -1) return Factory::null_value();
+  }
   ASSERT(last_match_info->HasFastElements());
 
   {
     NoHandleAllocation no_handles;
     FixedArray* array = FixedArray::cast(last_match_info->elements());
-    SetAtomLastCapture(array, *subject, value, value + needle->length());
+    SetAtomLastCapture(array, *subject, index, index + needle_len);
   }
   return last_match_info;
 }
 
 
 // Irregexp implementation.
 
 // Ensures that the regexp object contains a compiled version of the
 // source for either ASCII or non-ASCII strings.
 // If the compiled version doesn't already exist, it is compiled
@@ skipping 122 matching lines @@
                                 Handle<String> subject) {
   if (!subject->IsFlat()) {
     FlattenString(subject);
   }
   // Check the asciiness of the underlying storage.
   bool is_ascii;
   {
     AssertNoAllocation no_gc;
     String* sequential_string = *subject;
     if (subject->IsConsString()) {
-      sequential_string =  ConsString::cast(*subject)->first();
+      sequential_string = ConsString::cast(*subject)->first();
     }
     is_ascii = sequential_string->IsAsciiRepresentation();
   }
   if (!EnsureCompiledIrregexp(regexp, is_ascii)) {
     return -1;
   }
 #ifdef V8_INTERPRETED_REGEXP
   // Byte-code regexp needs space allocated for all its registers.
   return IrregexpNumberOfRegisters(FixedArray::cast(regexp->data()));
 #else  // V8_INTERPRETED_REGEXP
@@ skipping 4876 matching lines @@
                            node,
                            data->capture_count,
                            pattern);
 }
 
 
 int OffsetsVector::static_offsets_vector_[
     OffsetsVector::kStaticOffsetsVectorSize];
 
 }}  // namespace v8::internal