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| author | Thiago Macieira <thiago.macieira@nokia.com> | 2009-05-19 12:38:49 (GMT) |
|---|---|---|
| committer | Thiago Macieira <thiago.macieira@nokia.com> | 2009-05-22 12:17:57 (GMT) |
| commit | 1ff30b2b88af31cf18d2a1e6961c3ed7bd9b0240 (patch) | |
| tree | 8572f5ba08537661a62bfb36cff8c8e9fe27381e /tests/benchmarks | |
| parent | 2387c77787ec279981d58c46cfb5bde3e1530790 (diff) | |
| download | Qt-1ff30b2b88af31cf18d2a1e6961c3ed7bd9b0240.zip Qt-1ff30b2b88af31cf18d2a1e6961c3ed7bd9b0240.tar.gz Qt-1ff30b2b88af31cf18d2a1e6961c3ed7bd9b0240.tar.bz2 | |
Reintroduce the unaligned-unaligned 32-bit code that I had removed out of ignorance.
If both pointers are out of 4-byte alignment, doing the first load
will align them so we can do 32-bit comparisons. Lars's code had this
before, but I misunderstood it and removed, thinking it was doing
misaligned accesses.
I experimented with moving the tail comparison above the 32-bit
comparison to save a register, but it made things worse.
Reviewed-By: Bradley T. Hughes
Diffstat (limited to 'tests/benchmarks')
| -rw-r--r-- | tests/benchmarks/qstring/main.cpp | 41 |
1 files changed, 30 insertions, 11 deletions
diff --git a/tests/benchmarks/qstring/main.cpp b/tests/benchmarks/qstring/main.cpp index c7962bd..cbbf0a1 100644 --- a/tests/benchmarks/qstring/main.cpp +++ b/tests/benchmarks/qstring/main.cpp @@ -74,8 +74,8 @@ void tst_QString::equals_data() const 64, 64, 64, 64, 64, 64, 64, 64, // 48 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, // 64 - 64, 64, 64, 64, 64, 64, 64, 64, - 96, 96, 96, 96, 96, 96, 96, 96 // 80 + 64, 64, 64, 64, 96, 96, 96, 96, + 64, 64, 96, 96, 96, 96, 96, 96 // 80 }, 0 }; const QChar *ptr = reinterpret_cast<const QChar *>(data.data); @@ -88,15 +88,34 @@ void tst_QString::equals_data() const QTest::newRow("same-string") << base << base; QTest::newRow("same-data") << base << QString::fromRawData(ptr, 64); - // don't use length > 64, since that crosses a cache line - QTest::newRow("aligned-odd") - << QString::fromRawData(ptr, 63) << QString::fromRawData(ptr + 2, 63); - QTest::newRow("aligned-even") - << QString::fromRawData(ptr, 64) << QString::fromRawData(ptr + 2, 64); - QTest::newRow("unaligned-even") - << QString::fromRawData(ptr, 63) << QString::fromRawData(ptr + 1, 63); - QTest::newRow("unaligned-odd") - << QString::fromRawData(ptr, 64) << QString::fromRawData(ptr + 1, 64); + // try to avoid crossing a cache line (that is, at ptr[64]) + QTest::newRow("aligned-aligned-4n") + << QString::fromRawData(ptr, 60) << QString::fromRawData(ptr + 2, 60); + QTest::newRow("aligned-unaligned-4n") + << QString::fromRawData(ptr, 60) << QString::fromRawData(ptr + 1, 60); + QTest::newRow("unaligned-unaligned-4n") + << QString::fromRawData(ptr + 1, 60) << QString::fromRawData(ptr + 3, 60); + + QTest::newRow("aligned-aligned-4n+1") + << QString::fromRawData(ptr, 61) << QString::fromRawData(ptr + 2, 61); + QTest::newRow("aligned-unaligned-4n+1") + << QString::fromRawData(ptr, 61) << QString::fromRawData(ptr + 1, 61); + QTest::newRow("unaligned-unaligned-4n+1") + << QString::fromRawData(ptr + 1, 61) << QString::fromRawData(ptr + 3, 61); + + QTest::newRow("aligned-aligned-4n-1") + << QString::fromRawData(ptr, 59) << QString::fromRawData(ptr + 2, 59); + QTest::newRow("aligned-unaligned-4n-1") + << QString::fromRawData(ptr, 59) << QString::fromRawData(ptr + 1, 59); + QTest::newRow("unaligned-unaligned-4n-1") + << QString::fromRawData(ptr + 1, 59) << QString::fromRawData(ptr + 3, 59); + + QTest::newRow("aligned-aligned-2n") + << QString::fromRawData(ptr, 58) << QString::fromRawData(ptr + 2, 58); + QTest::newRow("aligned-unaligned-2n") + << QString::fromRawData(ptr, 58) << QString::fromRawData(ptr + 1, 58); + QTest::newRow("unaligned-unaligned-2n") + << QString::fromRawData(ptr + 1, 58) << QString::fromRawData(ptr + 3, 58); } QTEST_MAIN(tst_QString) |