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| author | Benjamin Poulain <benjamin.poulain@nokia.com> | 2010-02-23 15:05:38 (GMT) |
|---|---|---|
| committer | Benjamin Poulain <benjamin.poulain@nokia.com> | 2010-02-23 16:22:18 (GMT) |
| commit | d7181ae996f9add10bf4e956ddbedff99cb19378 (patch) | |
| tree | 8a0a348b9a504856b153fbbff4a49a702fb82a90 /src/corelib/tools/qsimd.cpp | |
| parent | 69abc957bca39bce4ed954b0469eb6abce8173fa (diff) | |
| download | Qt-d7181ae996f9add10bf4e956ddbedff99cb19378.zip Qt-d7181ae996f9add10bf4e956ddbedff99cb19378.tar.gz Qt-d7181ae996f9add10bf4e956ddbedff99cb19378.tar.bz2 | |
Cache the result of qDetectCPUFeatures()
Move the caching of the result from drawhelper to qsimd.cpp.
Avoid getting the environment variables when not necessary
Reviewed-by: Samuel Rødal
Diffstat (limited to 'src/corelib/tools/qsimd.cpp')
| -rw-r--r-- | src/corelib/tools/qsimd.cpp | 33 |
1 files changed, 26 insertions, 7 deletions
diff --git a/src/corelib/tools/qsimd.cpp b/src/corelib/tools/qsimd.cpp index 331a699..4ba8901 100644 --- a/src/corelib/tools/qsimd.cpp +++ b/src/corelib/tools/qsimd.cpp @@ -46,12 +46,18 @@ QT_BEGIN_NAMESPACE uint qDetectCPUFeatures() { + static uint features = 0xffffffff; + if (features != 0xffffffff) + return features; + #if defined (Q_OS_WINCE) #if defined (ARM) - if (IsProcessorFeaturePresent(PF_ARM_INTEL_WMMX)) - return IWMMXT; + if (IsProcessorFeaturePresent(PF_ARM_INTEL_WMMX)) { + features = IWMMXT; + return features; + } #elif defined(_X86_) - uint features = 0; + features = 0; #if defined QT_HAVE_MMX if (IsProcessorFeaturePresent(PF_MMX_INSTRUCTIONS_AVAILABLE)) features |= MMX; @@ -62,16 +68,19 @@ uint qDetectCPUFeatures() #endif return features; #endif - return 0; + features = 0; + return features; #elif defined(QT_HAVE_IWMMXT) // runtime detection only available when running as a previlegied process static const bool doIWMMXT = !qgetenv("QT_NO_IWMMXT").toInt(); - return doIWMMXT ? IWMMXT : 0; + features = doIWMMXT ? IWMMXT : 0 + return features; #elif defined(QT_HAVE_NEON) static const bool doNEON = !qgetenv("QT_NO_NEON").toInt(); - return doNEON ? NEON : 0; + features = doNEON ? NEON : 0 + return features; #else - uint features = 0; + features = 0; #if defined(__x86_64__) || defined(Q_OS_WIN64) features = MMX|SSE|SSE2|CMOV; #elif defined(__ia64__) @@ -207,18 +216,28 @@ uint qDetectCPUFeatures() features |= SSE2; #endif // i386 +#if defined(QT_HAVE_MMX) if (qgetenv("QT_NO_MMX").toInt()) features ^= MMX; +#endif if (qgetenv("QT_NO_MMXEXT").toInt()) features ^= MMXEXT; + +#if defined(QT_HAVE_3DNOW) if (qgetenv("QT_NO_3DNOW").toInt()) features ^= MMX3DNOW; +#endif if (qgetenv("QT_NO_3DNOWEXT").toInt()) features ^= MMX3DNOWEXT; + +#if defined(QT_HAVE_SSE) if (qgetenv("QT_NO_SSE").toInt()) features ^= SSE; +#endif +#if defined(QT_HAVE_SSE2) if (qgetenv("QT_NO_SSE2").toInt()) features ^= SSE2; +#endif return features; #endif |