diff options
| -rw-r--r-- | src/corelib/codecs/qutfcodec.cpp | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/src/corelib/codecs/qutfcodec.cpp b/src/corelib/codecs/qutfcodec.cpp index ce1b092a54..08cc99f4dc 100644 --- a/src/corelib/codecs/qutfcodec.cpp +++ b/src/corelib/codecs/qutfcodec.cpp @@ -155,6 +155,28 @@ static inline bool simdDecodeAscii(ushort *&dst, const uchar *&nextAscii, const static inline const uchar *simdFindNonAscii(const uchar *src, const uchar *end, const uchar *&nextAscii) { +#ifdef __AVX2__ + // do 32 characters at a time + // (this is similar to simdTestMask in qstring.cpp) + const __m256i mask = _mm256_set1_epi8(0x80); + for ( ; end - src >= 32; src += 32) { + __m256i data = _mm256_loadu_si256(reinterpret_cast<const __m256i *>(src)); + if (_mm256_testz_si256(mask, data)) + continue; + + uint n = _mm256_movemask_epi8(data); + Q_ASSUME(n); + + // find the next probable ASCII character + // we don't want to load 32 bytes again in this loop if we know there are non-ASCII + // characters still coming + nextAscii = src + qBitScanReverse(n) + 1; + + // return the non-ASCII character + return src + qCountTrailingZeroBits(n); + } +#endif + // do sixteen characters at a time for ( ; end - src >= 16; src += 16) { __m128i data = _mm_loadu_si128(reinterpret_cast<const __m128i*>(src)); |