Modified: trunk/Source/_javascript_Core/ChangeLog (92539 => 92540)
--- trunk/Source/_javascript_Core/ChangeLog 2011-08-06 02:07:55 UTC (rev 92539)
+++ trunk/Source/_javascript_Core/ChangeLog 2011-08-06 02:17:55 UTC (rev 92540)
@@ -1,3 +1,16 @@
+2011-08-05 Gavin Barraclough <[email protected]>
+
+ String replace with the empty string means string removal
+ https://bugs.webkit.org/show_bug.cgi?id=65799
+
+ Reviewed by Sam Weinig.
+
+ Optimization for String.prototype.replace([RegExp], ""), this improves v8-regexp by ~3%.
+
+ * runtime/StringPrototype.cpp:
+ (JSC::jsSpliceSubstrings):
+ (JSC::stringProtoFuncReplace):
+
2011-08-05 Noel Gordon <[email protected]>
[Chromium] Remove JSZombie references from gyp project files.
Modified: trunk/Source/_javascript_Core/runtime/StringPrototype.cpp (92539 => 92540)
--- trunk/Source/_javascript_Core/runtime/StringPrototype.cpp 2011-08-06 02:07:55 UTC (rev 92539)
+++ trunk/Source/_javascript_Core/runtime/StringPrototype.cpp 2011-08-06 02:17:55 UTC (rev 92540)
@@ -248,6 +248,41 @@
int length;
};
+static ALWAYS_INLINE JSValue jsSpliceSubstrings(ExecState* exec, JSString* sourceVal, const UString& source, const StringRange* substringRanges, int rangeCount)
+{
+ if (rangeCount == 1) {
+ int sourceSize = source.length();
+ int position = substringRanges[0].position;
+ int length = substringRanges[0].length;
+ if (position <= 0 && length >= sourceSize)
+ return sourceVal;
+ // We could call UString::substr, but this would result in redundant checks
+ return jsString(exec, StringImpl::create(source.impl(), max(0, position), min(sourceSize, length)));
+ }
+
+ int totalLength = 0;
+ for (int i = 0; i < rangeCount; i++)
+ totalLength += substringRanges[i].length;
+
+ if (!totalLength)
+ return jsString(exec, "");
+
+ UChar* buffer;
+ RefPtr<StringImpl> impl = StringImpl::tryCreateUninitialized(totalLength, buffer);
+ if (!impl)
+ return throwOutOfMemoryError(exec);
+
+ int bufferPos = 0;
+ for (int i = 0; i < rangeCount; i++) {
+ if (int srcLen = substringRanges[i].length) {
+ StringImpl::copyChars(buffer + bufferPos, source.characters() + substringRanges[i].position, srcLen);
+ bufferPos += srcLen;
+ }
+ }
+
+ return jsString(exec, impl.release());
+}
+
static ALWAYS_INLINE JSValue jsSpliceSubstringsWithSeparators(ExecState* exec, JSString* sourceVal, const UString& source, const StringRange* substringRanges, int rangeCount, const UString* separators, int separatorCount)
{
if (rangeCount == 1 && separatorCount == 0) {
@@ -266,11 +301,11 @@
for (int i = 0; i < separatorCount; i++)
totalLength += separators[i].length();
- if (totalLength == 0)
+ if (!totalLength)
return jsString(exec, "");
UChar* buffer;
- PassRefPtr<StringImpl> impl = StringImpl::tryCreateUninitialized(totalLength, buffer);
+ RefPtr<StringImpl> impl = StringImpl::tryCreateUninitialized(totalLength, buffer);
if (!impl)
return throwOutOfMemoryError(exec);
@@ -291,7 +326,7 @@
}
}
- return jsString(exec, impl);
+ return jsString(exec, impl.release());
}
EncodedJSValue JSC_HOST_CALL stringProtoFuncReplace(ExecState* exec)
@@ -320,6 +355,44 @@
RegExpConstructor* regExpConstructor = exec->lexicalGlobalObject()->regExpConstructor();
+ // Optimization for substring removal (replace with empty).
+ if (global && callType == CallTypeNone && !replacementString.length()) {
+ int lastIndex = 0;
+ unsigned startPosition = 0;
+
+ Vector<StringRange, 16> sourceRanges;
+
+ while (true) {
+ int matchIndex;
+ int matchLen = 0;
+ int* ovector;
+ regExpConstructor->performMatch(*globalData, reg, source, startPosition, matchIndex, matchLen, &ovector);
+ if (matchIndex < 0)
+ break;
+
+ if (lastIndex < matchIndex)
+ sourceRanges.append(StringRange(lastIndex, matchIndex - lastIndex));
+
+ lastIndex = matchIndex + matchLen;
+ startPosition = lastIndex;
+
+ // special case of empty match
+ if (!matchLen) {
+ startPosition++;
+ if (startPosition > sourceLen)
+ break;
+ }
+ }
+
+ if (!lastIndex)
+ return JSValue::encode(sourceVal);
+
+ if (static_cast<unsigned>(lastIndex) < sourceLen)
+ sourceRanges.append(StringRange(lastIndex, sourceLen - lastIndex));
+
+ return JSValue::encode(jsSpliceSubstrings(exec, sourceVal, source, sourceRanges.data(), sourceRanges.size()));
+ }
+
int lastIndex = 0;
unsigned startPosition = 0;
@@ -372,7 +445,7 @@
startPosition = lastIndex;
// special case of empty match
- if (matchLen == 0) {
+ if (!matchLen) {
startPosition++;
if (startPosition > sourceLen)
break;
@@ -425,7 +498,7 @@
startPosition = lastIndex;
// special case of empty match
- if (matchLen == 0) {
+ if (!matchLen) {
startPosition++;
if (startPosition > sourceLen)
break;
