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| author | Thiago Macieira <thiago.macieira@nokia.com> | 2010-08-12 22:59:27 (GMT) |
|---|---|---|
| committer | Thiago Macieira <thiago.macieira@nokia.com> | 2010-08-24 10:36:33 (GMT) |
| commit | a9dae34157aeef00512bea49f11a8dd1895f676b (patch) | |
| tree | 9ef3d5e6e97fe55a4f73c4e7588f6e25f80ce4cd /tests/benchmarks | |
| parent | 7790cf5b2922a7adf684dc0b7cd0fc1583c0684a (diff) | |
| download | Qt-a9dae34157aeef00512bea49f11a8dd1895f676b.zip Qt-a9dae34157aeef00512bea49f11a8dd1895f676b.tar.gz Qt-a9dae34157aeef00512bea49f11a8dd1895f676b.tar.bz2 | |
Add an SSE4.2 version of the string comparison
It's currently slightly worse than SSE2 with prolog aligning
(i.e., it's no good)
Diffstat (limited to 'tests/benchmarks')
| -rw-r--r-- | tests/benchmarks/corelib/tools/qstring/main.cpp | 41 | ||||
| -rw-r--r-- | tests/benchmarks/corelib/tools/qstring/qstring.pro | 3 |
2 files changed, 43 insertions, 1 deletions
diff --git a/tests/benchmarks/corelib/tools/qstring/main.cpp b/tests/benchmarks/corelib/tools/qstring/main.cpp index e1800c0..1c55f82 100644 --- a/tests/benchmarks/corelib/tools/qstring/main.cpp +++ b/tests/benchmarks/corelib/tools/qstring/main.cpp @@ -378,6 +378,41 @@ static bool equals2_ssse3(ushort *p1, ushort *p2, int len) return equals2_shortwise(p1, p2, len); } //#endif + +//#ifdef __SSE4_1__ +static bool equals2_sse4(ushort *p1, ushort *p2, int len) +{ + // We use the pcmpestrm instruction searching for differences (negative polarity) + // it will reset CF if it's all equal + // it will reset OF if the first char is equal + // it will set ZF & SF if the length is less than 8 (which means we've done the last operation) + // the three possible conditions are: + // difference found: CF = 1 + // all equal, not finished: CF = ZF = SF = 0 + // all equal, finished: CF = 0, ZF = SF = 1 + len += 8; + asm ( + "0:\n\t" + "movdqu (%[p1]), %%xmm0\n\t" // load 8 ushorts + "movdqu (%[p2]), %%xmm1\n\t" + "addl $16, %[p2]\n\t" + "addl $16, %[p1]\n\t" + "subl $8, %[len]\n\t" + "movl %[len], %%edx\n\t" + "pcmpestrm %[mode], %%xmm1, %%xmm0\n\t" + "ja 0b\n\t" + "1:\n\t" + "mov $0, %[len]\n\t" + "setnc %%al\n\t" + : [len] "+a" (len) + : [p1] "r" (p1), + [p2] "r" (p2), + [mode] "K" (_SIDD_UWORD_OPS | _SIDD_CMP_EQUAL_EACH | _SIDD_NEGATIVE_POLARITY | _SIDD_UNIT_MASK) + : "%edx", "%xmm0", "%xmm1" + ); + return len; +} +//#endif #endif void tst_QString::equals2_data() const @@ -393,6 +428,9 @@ void tst_QString::equals2_data() const QTest::newRow("sse2_aligning") << 5; #ifdef __SSSE3__ QTest::newRow("ssse3") << 6; +#ifdef __SSE4_1__ + QTest::newRow("sse4.2") << 7; +#endif #endif #endif } @@ -447,6 +485,9 @@ void tst_QString::equals2() const equals2_sse2_aligning, // 5 #ifdef __SSSE3__ equals2_ssse3, // 6 +#ifdef __SSE4_1__ + equals2_sse4, // 7 +#endif #endif #endif 0 diff --git a/tests/benchmarks/corelib/tools/qstring/qstring.pro b/tests/benchmarks/corelib/tools/qstring/qstring.pro index bc6254c..44fb46b 100644 --- a/tests/benchmarks/corelib/tools/qstring/qstring.pro +++ b/tests/benchmarks/corelib/tools/qstring/qstring.pro @@ -14,5 +14,6 @@ wince*:{ DEFINES += SRCDIR=\\\"$$PWD/\\\" } -ssse3:QMAKE_FLAGS += -mssse3 +sse4:QMAKE_CXXFLAGS += -msse4 +else:ssse3:QMAKE_FLAGS += -mssse3 else:sse2:QMAKE_CXXFLAGS += -msse2 |