diff options
| -rw-r--r-- | src/corelib/tools/qstring.cpp | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/src/corelib/tools/qstring.cpp b/src/corelib/tools/qstring.cpp index 3689e5aaeb..c6af05c73e 100644 --- a/src/corelib/tools/qstring.cpp +++ b/src/corelib/tools/qstring.cpp @@ -491,6 +491,30 @@ static int ucstrncmp(const QChar *a, const QChar *b, int l) return UnrollTailLoop<7>::exec(l, 0, lambda, lambda); # endif #endif +#if defined(__ARM_NEON__) && defined(Q_PROCESSOR_ARM_64) // vaddv is only available on Aarch64 + if (l >= 8) { + const QChar *end = a + l; + const uint16x8_t mask = { 1, 1 << 1, 1 << 2, 1 << 3, 1 << 4, 1 << 5, 1 << 6, 1 << 7 }; + while (a + 8 < end) { + uint16x8_t da = vld1q_u16(reinterpret_cast<const uint16_t *>(a)); + uint16x8_t db = vld1q_u16(reinterpret_cast<const uint16_t *>(b)); + + uint8_t r = ~(uint8_t)vaddvq_u16(vandq_u16(vceqq_u16(da, db), mask)); + if (r) { + // found a different QChar + uint idx = qCountTrailingZeroBits(r); + return (int)a[idx].unicode() - (int)b[idx].unicode(); + } + a += 8; + b += 8; + } + l &= 7; + } + const auto &lambda = [=](int i) -> int { + return a[i].unicode() - b[i].unicode(); + }; + return UnrollTailLoop<7>::exec(l, 0, lambda, lambda); +#endif // __ARM_NEON__ if (!l) return 0; |