Author: [email protected]
Date: Tue Jun 16 06:31:31 2009
New Revision: 2191
Modified:
branches/bleeding_edge/src/objects-inl.h
branches/bleeding_edge/src/string.js
Log:
- Changed fast case for computing object size based on usage histogram.
- Added fast case to String.prototype.split (Mads's idea).
- Made minor other optimizations in String.prototype.split.
Review URL: http://codereview.chromium.org/126201
Modified: branches/bleeding_edge/src/objects-inl.h
==============================================================================
--- branches/bleeding_edge/src/objects-inl.h (original)
+++ branches/bleeding_edge/src/objects-inl.h Tue Jun 16 06:31:31 2009
@@ -1786,10 +1786,16 @@
int HeapObject::SizeFromMap(Map* map) {
InstanceType instance_type = map->instance_type();
- // Only inline the two most frequent cases.
- if (instance_type == JS_OBJECT_TYPE) return map->instance_size();
+ // Only inline the most frequent cases.
+ if (instance_type == JS_OBJECT_TYPE ||
+ (instance_type & (kIsNotStringMask | kStringRepresentationMask)) ==
+ (kStringTag | kConsStringTag) ||
+ instance_type == JS_ARRAY_TYPE) return map->instance_size();
if (instance_type == FIXED_ARRAY_TYPE) {
return reinterpret_cast<FixedArray*>(this)->FixedArraySize();
+ }
+ if (instance_type == BYTE_ARRAY_TYPE) {
+ return reinterpret_cast<ByteArray*>(this)->ByteArraySize();
}
// Otherwise do the general size computation.
return SlowSizeFromMap(map);
Modified: branches/bleeding_edge/src/string.js
==============================================================================
--- branches/bleeding_edge/src/string.js (original)
+++ branches/bleeding_edge/src/string.js Tue Jun 16 06:31:31 2009
@@ -370,10 +370,10 @@
// 'abcd'.replace(/(.)/g, function() { return RegExp.$1; }
// should be 'abcd' and not 'dddd' (or anything else).
function StringReplaceRegExpWithFunction(subject, regexp, replace) {
- var result = new ReplaceResultBuilder(subject);
var lastMatchInfo = DoRegExpExec(regexp, subject, 0);
if (IS_NULL(lastMatchInfo)) return subject;
+ var result = new ReplaceResultBuilder(subject);
// There's at least one match. If the regexp is global, we have to loop
// over all matches. The loop is not in C++ code here like the one in
// RegExp.prototype.exec, because of the interleaved function
application.
@@ -498,10 +498,8 @@
// ECMA-262 section 15.5.4.14
function StringSplit(separator, limit) {
var subject = ToString(this);
- var result = [];
- var lim = (limit === void 0) ? 0xffffffff : ToUint32(limit);
-
- if (lim === 0) return result;
+ limit = (limit === void 0) ? 0xffffffff : ToUint32(limit);
+ if (limit === 0) return [];
// ECMA-262 says that if separator is undefined, the result should
// be an array of size 1 containing the entire string. SpiderMonkey
@@ -509,28 +507,31 @@
// undefined is explicitly given, they convert it to a string and
// use that. We do as SpiderMonkey and KJS.
if (%_ArgumentsLength() === 0) {
- result[result.length] = subject;
- return result;
+ return [subject];
}
var length = subject.length;
- var currentIndex = 0;
- var startIndex = 0;
-
- var sep;
if (IS_REGEXP(separator)) {
- sep = separator;
- %_Log('regexp', 'regexp-split,%0S,%1r', [subject, sep]);
+ %_Log('regexp', 'regexp-split,%0S,%1r', [subject, separator]);
} else {
- sep = ToString(separator);
+ separator = ToString(separator);
+ // If the separator string is empty then return the elements in the
subject.
+ if (separator.length == 0) {
+ var result = $Array(length);
+ for (var i = 0; i < length; i++) result[i] = subject[i];
+ return result;
+ }
}
if (length === 0) {
- if (splitMatch(sep, subject, 0, 0) != null) return result;
- result[result.length] = subject;
- return result;
+ if (splitMatch(separator, subject, 0, 0) != null) return [];
+ return [subject];
}
+ var currentIndex = 0;
+ var startIndex = 0;
+ var result = [];
+
while (true) {
if (startIndex === length) {
@@ -538,7 +539,7 @@
return result;
}
- var lastMatchInfo = splitMatch(sep, subject, currentIndex, startIndex);
+ var lastMatchInfo = splitMatch(separator, subject, currentIndex,
startIndex);
if (IS_NULL(lastMatchInfo)) {
result[result.length] = subject.slice(currentIndex, length);
@@ -553,21 +554,18 @@
continue;
}
- result[result.length] =
- SubString(subject, currentIndex, lastMatchInfo[CAPTURE0]);
- if (result.length === lim) return result;
+ result[result.length] = SubString(subject, currentIndex,
lastMatchInfo[CAPTURE0]);
+ if (result.length === limit) return result;
for (var i = 2; i < NUMBER_OF_CAPTURES(lastMatchInfo); i += 2) {
var start = lastMatchInfo[CAPTURE(i)];
var end = lastMatchInfo[CAPTURE(i + 1)];
if (start != -1 && end != -1) {
- result[result.length] = SubString(subject,
- lastMatchInfo[CAPTURE(i)],
- lastMatchInfo[CAPTURE(i + 1)]);
+ result[result.length] = SubString(subject, start, end);
} else {
result[result.length] = void 0;
}
- if (result.length === lim) return result;
+ if (result.length === limit) return result;
}
startIndex = currentIndex = endIndex;
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