Improve regexp split, replace and test.

src/regexp.js

 // 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 14 matching lines @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 // Expect $Object = global.Object;
 // Expect $Array = global.Array;
 
 const $RegExp = global.RegExp;
 
 // A recursive descent parser for Patterns according to the grammar of
 // ECMA-262 15.10.1, with deviations noted below.
-function DoConstructRegExp(object, pattern, flags, isConstructorCall) {
+function DoConstructRegExp(object, pattern, flags) {
   // RegExp : Called as constructor; see ECMA-262, section 15.10.4.
   if (IS_REGEXP(pattern)) {
     if (!IS_UNDEFINED(flags)) {
       throw MakeTypeError('regexp_flags', []);
     }
     flags = (pattern.global ? 'g' : '')
         + (pattern.ignoreCase ? 'i' : '')
         + (pattern.multiline ? 'm' : '');
     pattern = pattern.source;
   }
@@ skipping 27 matching lines @@
 
   %RegExpInitializeObject(object, pattern, global, ignoreCase, multiline);
 
   // Call internal function to compile the pattern.
   %RegExpCompile(object, pattern, flags);
 }
 
 
 function RegExpConstructor(pattern, flags) {
   if (%_IsConstructCall()) {
-    DoConstructRegExp(this, pattern, flags, true);
+    DoConstructRegExp(this, pattern, flags);
   } else {
     // RegExp : Called as function; see ECMA-262, section 15.10.3.1.
     if (IS_REGEXP(pattern) && IS_UNDEFINED(flags)) {
       return pattern;
     }
     return new $RegExp(pattern, flags);
   }
 }
 
 
 // Deprecated RegExp.prototype.compile method.  We behave like the constructor
 // were called again.  In SpiderMonkey, this method returns the regexp object.
 // In JSC, it returns undefined.  For compatibility with JSC, we match their
 // behavior.
 function CompileRegExp(pattern, flags) {
   // Both JSC and SpiderMonkey treat a missing pattern argument as the
   // empty subject string, and an actual undefined value passed as the
   // pattern as the string 'undefined'.  Note that JSC is inconsistent
   // here, treating undefined values differently in
   // RegExp.prototype.compile and in the constructor, where they are
   // the empty string.  For compatibility with JSC, we match their
   // behavior.
   if (IS_UNDEFINED(pattern) && %_ArgumentsLength() != 0) {
-    DoConstructRegExp(this, 'undefined', flags, false);
+    DoConstructRegExp(this, 'undefined', flags);
   } else {
-    DoConstructRegExp(this, pattern, flags, false);
+    DoConstructRegExp(this, pattern, flags);
   }
 }
 
 
 function DoRegExpExec(regexp, string, index) {
   var result = %_RegExpExec(regexp, string, index, lastMatchInfo);
   if (result !== null) lastMatchInfoOverride = null;
   return result;
 }
 
@@ skipping 23 matching lines @@
       // property from the global object since this may change.
       result[i] = void 0;
     }
   }
   return result;
 }
 
 
 function RegExpExecNoTests(regexp, string, start) {
   // Must be called with RegExp, string and positive integer as arguments.
-  var matchInfo = DoRegExpExec(regexp, string, start);
-  var result = null;
+  var matchInfo = %_RegExpExec(regexp, string, start, lastMatchInfo);
   if (matchInfo !== null) {
-    result = BuildResultFromMatchInfo(matchInfo, string);
+    lastMatchInfoOverride = null;
+    return BuildResultFromMatchInfo(matchInfo, string);
   }
-  return result;
+  return null;
 }
 
 
 function RegExpExec(string) {
   if (!IS_REGEXP(this)) {
     throw MakeTypeError('incompatible_method_receiver',
                         ['RegExp.prototype.exec', this]);
   }
 
   if (%_ArgumentsLength() === 0) {
@@ skipping 85 matching lines @@
   } else {
     // Non-global regexp.
     // Remove irrelevant preceeding '.*' in a non-global test regexp. 
     // The expression checks whether this.source starts with '.*' and 
     // that the third char is not a '?'.
     if (%_StringCharCodeAt(this.source, 0) == 46 &&  // '.'
         %_StringCharCodeAt(this.source, 1) == 42 &&  // '*'
         %_StringCharCodeAt(this.source, 2) != 63) {  // '?'
       if (!%_ObjectEquals(regexp_key, this)) {
         regexp_key = this;
-        regexp_val = new $RegExp(this.source.substring(2, this.source.length),
+        regexp_val = new $RegExp(SubString(this.source, 2, this.source.length),
                                  (this.ignoreCase ? 'i' : '')

[Lasse Reichstein, 2010/12/17 10:38:30]

How about:
  (this.ignoreCase ? this.multiline ? "im" : "i" : this.multiline ? "m" : "")
to avoid the string-concatenation?

[sandholm, 2010/12/17 11:50:24]

Done.

                                  + (this.multiline ? 'm' : ''));
       }
-      if (!regexp_val.test(string)) return false;
+      if (%_RegExpExec(regexp_val, string, 0, lastMatchInfo) === null) {

[Lasse Reichstein, 2010/12/17 10:38:30]

Use DoRegExpExec, or remember to clear lastMatchIndoOverride.

[sandholm, 2010/12/17 11:50:24]

The result is only used if there was no match. Otherwise, the "actual" exec call
is made below in which case the lastMatchInfoOverride gets overridden.

+        return false;
+      }
     }    
     %_Log('regexp', 'regexp-exec,%0r,%1S,%2i', [this, string, lastIndex]);
     // matchIndices is either null or the lastMatchInfo array.
     var matchIndices = %_RegExpExec(this, string, 0, lastMatchInfo);
     if (matchIndices === null) return false;
     lastMatchInfoOverride = null;
     return true;
   }
 }
 
@@ skipping 192 matching lines @@
   %DefineAccessor($RegExp, "$'", SETTER, NoOpSetter, DONT_ENUM | DONT_DELETE);
 
   for (var i = 1; i < 10; ++i) {
     %DefineAccessor($RegExp, '$' + i, GETTER, RegExpMakeCaptureGetter(i), DONT_DELETE);
     %DefineAccessor($RegExp, '$' + i, SETTER, NoOpSetter, DONT_DELETE);
   }
 }
 
 
 SetupRegExp();