jsSubstring() should be lazy
https://bugs.webkit.org/show_bug.cgi?id=132556
Reviewed by Andreas Kling.
Source/JavaScriptCore:
jsSubstring() is now lazy by using a special rope that is a substring instead of a
concatenation. To make this patch super simple, we require that a substring's base is
never a rope. Hence, when resolving a rope, we either go down a non-recursive substring
path, or we go down a concatenation path which may see exactly one level of substrings in
its fibers.
This is up to a 50% speed-up on microbenchmarks and a 10% speed-up on Octane/regexp.
* heap/MarkedBlock.cpp:
(JSC::MarkedBlock::specializedSweep):
* runtime/JSString.cpp:
(JSC::JSRopeString::visitFibers):
(JSC::JSRopeString::resolveRope):
(JSC::JSRopeString::resolveRopeSlowCase8):
(JSC::JSRopeString::resolveRopeSlowCase):
(JSC::JSRopeString::outOfMemory):
* runtime/JSString.h:
(JSC::JSRopeString::finishCreation):
(JSC::JSRopeString::append):
(JSC::JSRopeString::create):
(JSC::JSRopeString::offsetOfFibers):
(JSC::JSRopeString::fiber):
(JSC::JSRopeString::substringBase):
(JSC::JSRopeString::substringOffset):
(JSC::JSRopeString::substringSentinel):
(JSC::JSRopeString::isSubstring):
(JSC::jsSubstring):
* runtime/RegExpMatchesArray.cpp:
(JSC::RegExpMatchesArray::reifyAllProperties):
* runtime/StringPrototype.cpp:
(JSC::stringProtoFuncSubstring):
LayoutTests:
These tests get 35-50% faster.
* js/regress/script-tests/substring-concat-weird.js: Added.
(foo):
* js/regress/script-tests/substring-concat.js: Added.
(foo):
* js/regress/script-tests/substring.js: Added.
(foo):
* js/regress/substring-concat-expected.txt: Added.
* js/regress/substring-concat-weird-expected.txt: Added.
* js/regress/substring-concat-weird.html: Added.
* js/regress/substring-concat.html: Added.
* js/regress/substring-expected.txt: Added.
* js/regress/substring.html: Added.
git-svn-id: http://svn.webkit.org/repository/webkit/trunk@168254 268f45cc-cd09-0410-ab3c-d52691b4dbfc
16 files changed
