diff options
| author | Thiago Macieira <thiago.macieira@intel.com> | 2018-05-09 19:56:30 -0700 |
|---|---|---|
| committer | Thiago Macieira <thiago.macieira@intel.com> | 2018-05-15 23:04:46 +0000 |
| commit | 9d0907b07606ab4da16ae67aac9523fce7ff9525 (patch) | |
| tree | 9a724ff20c5c76778b12c43aac3ced08653b2c81 /src/corelib/tools/qstring.cpp | |
| parent | 65711d7aeac1b398c4aa45e5e73aeb500d6aab6b (diff) | |
QUrl: use the SIMD ASCII-checking code from the last commit
Improves performance a little. This is just because I can and the
function is right there for the taking, as this qt_urlRecodeByteArray
function is only used in deprecated QUrl code.
Change-Id: I5d0ee9389a794d80983efffd152d290e570af387
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>
Diffstat (limited to 'src/corelib/tools/qstring.cpp')
| -rw-r--r-- | src/corelib/tools/qstring.cpp | 25 |
1 files changed, 19 insertions, 6 deletions
diff --git a/src/corelib/tools/qstring.cpp b/src/corelib/tools/qstring.cpp index 773b15032d4..719c685f697 100644 --- a/src/corelib/tools/qstring.cpp +++ b/src/corelib/tools/qstring.cpp @@ -333,11 +333,10 @@ static bool simdTestMask(const char *&ptr, const char *end, quint32 maskval) } #endif -bool QtPrivate::isAscii(QLatin1String s) Q_DECL_NOTHROW +// Note: ptr on output may be off by one and point to a preceding US-ASCII +// character. Usually harmless. +bool qt_is_ascii(const char *&ptr, const char *end) Q_DECL_NOTHROW { - const char *ptr = s.begin(); - const char *end = s.end(); - #if defined(__AVX2__) if (!simdTestMask(ptr, end, 0x80808080)) return false; @@ -346,16 +345,22 @@ bool QtPrivate::isAscii(QLatin1String s) Q_DECL_NOTHROW while (ptr + 16 < end) { __m128i data = _mm_loadu_si128(reinterpret_cast<const __m128i *>(ptr)); quint32 mask = _mm_movemask_epi8(data); - if (mask) + if (mask) { + uint idx = qCountTrailingZeroBits(mask); + ptr += idx; return false; + } ptr += 16; } #endif while (ptr + 4 <= end) { quint32 data = qFromUnaligned<quint32>(ptr); - if (data & 0x80808080U) + if (data &= 0x80808080U) { + uint idx = qCountTrailingZeroBits(data); + ptr += idx / 8; return false; + } ptr += 4; } @@ -367,6 +372,14 @@ bool QtPrivate::isAscii(QLatin1String s) Q_DECL_NOTHROW return true; } +bool QtPrivate::isAscii(QLatin1String s) Q_DECL_NOTHROW +{ + const char *ptr = s.begin(); + const char *end = s.end(); + + return qt_is_ascii(ptr, end); +} + static bool isAscii(const QChar *&ptr, const QChar *end) { #ifdef __SSE2__ |