diff options
| author | michael.bruning@digia.com <michael.bruning@digia.com@268f45cc-cd09-0410-ab3c-d52691b4dbfc> | 2013-07-10 08:36:13 +0000 |
|---|---|---|
| committer | The Qt Project <gerrit-noreply@qt-project.org> | 2013-07-10 11:05:12 +0200 |
| commit | 42a16bccb1750f0e4094d9d6366200a5deae9184 (patch) | |
| tree | 8723c361f7a3ebb43730aeb077c5c7a896df103c | |
| parent | e547fc9a9d1d6826cc9bb39c20331c4eff444d42 (diff) | |
| download | qtwebkit-42a16bccb1750f0e4094d9d6366200a5deae9184.tar.gz | |
Workaround for x86 optimizer bug in MSVC 2012.
https://bugs.webkit.org/show_bug.cgi?id=118478
Reviewed by Benjamin Poulain.
This is a workaround for a bug in the x86 MSVC 2012 optimizer.
The problem is that the range comparison gets optimized out when
the templated inline function toASCIIUpper. Copying the methods
content fixes the problem.
This is unfortunately not the nicest fix, but the alternative would
be to turn off optimization for StringImpl::upper on the x86 MSVC 2012
build, which might impact overall performance negatively.
* wtf/text/StringImpl.cpp:
(WTF::StringImpl::upper):
git-svn-id: http://svn.webkit.org/repository/webkit/trunk@152529 268f45cc-cd09-0410-ab3c-d52691b4dbfc
Change-Id: Ia08780b3b2216a10fb7a7beb8b7298b84726417a
Task-number: QTBUG-32159
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
| -rw-r--r-- | Source/WTF/wtf/text/StringImpl.cpp | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/Source/WTF/wtf/text/StringImpl.cpp b/Source/WTF/wtf/text/StringImpl.cpp index f995c6414..0c8da50ff 100644 --- a/Source/WTF/wtf/text/StringImpl.cpp +++ b/Source/WTF/wtf/text/StringImpl.cpp @@ -480,7 +480,14 @@ PassRefPtr<StringImpl> StringImpl::upper() for (int i = 0; i < length; ++i) { LChar c = m_data8[i]; ored |= c; +#if CPU(X86) && defined(_MSC_VER) && _MSC_VER >=1700 + // Workaround for an MSVC 2012 x86 optimizer bug. Remove once the bug is fixed. + // See https://connect.microsoft.com/VisualStudio/feedback/details/780362/optimization-bug-of-range-comparison + // for more details. + data8[i] = c >= 'a' && c <= 'z' ? c & ~0x20 : c; +#else data8[i] = toASCIIUpper(c); +#endif } if (!(ored & ~0x7F)) return newImpl.release(); |