diff options
| -rw-r--r-- | src/corelib/tools/qhash.cpp | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/src/corelib/tools/qhash.cpp b/src/corelib/tools/qhash.cpp index 7520158293..ec7ce94ed0 100644 --- a/src/corelib/tools/qhash.cpp +++ b/src/corelib/tools/qhash.cpp @@ -130,6 +130,55 @@ static uint crc32(const Char *ptr, size_t len, uint h) h = _mm_crc32_u8(h, *p); return h; } +#elif defined(Q_PROCESSOR_ARM_V8) +static inline bool hasFastCrc32() +{ + return qCpuHasFeature(CRC32); +} + +template <typename Char> +QT_FUNCTION_TARGET(CRC32) +static uint crc32(const Char *ptr, size_t len, uint h) +{ + // The crc32[whbd] instructions on Aarch64/Aarch32 calculate a 32-bit CRC32 checksum + const uchar *p = reinterpret_cast<const uchar *>(ptr); + const uchar *const e = p + (len * sizeof(Char)); + +#ifndef __ARM_FEATURE_UNALIGNED + if (Q_UNLIKELY(reinterpret_cast<quintptr>(p) & 7)) { + if ((sizeof(Char) == 1) && (reinterpret_cast<quintptr>(p) & 1) && (e - p > 0)) { + h = __crc32b(h, *p); + ++p; + } + if ((reinterpret_cast<quintptr>(p) & 2) && (e >= p + 2)) { + h = __crc32h(h, *reinterpret_cast<const uint16_t *>(p)); + p += 2; + } + if ((reinterpret_cast<quintptr>(p) & 4) && (e >= p + 4)) { + h = __crc32w(h, *reinterpret_cast<const uint32_t *>(p)); + p += 4; + } + } +#endif + + for ( ; p + 8 <= e; p += 8) + h = __crc32d(h, *reinterpret_cast<const uint64_t *>(p)); + + len = e - p; + if (len == 0) + return h; + if (len & 4) { + h = __crc32w(h, *reinterpret_cast<const uint32_t *>(p)); + p += 4; + } + if (len & 2) { + h = __crc32h(h, *reinterpret_cast<const uint16_t *>(p)); + p += 2; + } + if (sizeof(Char) == 1 && len & 1) + h = __crc32b(h, *p); + return h; +} #else static inline bool hasFastCrc32() { |