1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/content/base/src/nsTextFragmentSSE2.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,72 @@
1.4 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.5 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.6 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.7 +
1.8 +// This file should only be compiled if you're on x86 or x86_64. Additionally,
1.9 +// you'll need to compile this file with -msse2 if you're using gcc.
1.10 +
1.11 +#include <emmintrin.h>
1.12 +#include "nscore.h"
1.13 +#include "nsAlgorithm.h"
1.14 +#include "nsTextFragmentImpl.h"
1.15 +#include <algorithm>
1.16 +
1.17 +namespace mozilla {
1.18 +namespace SSE2 {
1.19 +
1.20 +static inline bool
1.21 +is_zero (__m128i x)
1.22 +{
1.23 + return
1.24 + _mm_movemask_epi8(_mm_cmpeq_epi8(x, _mm_setzero_si128())) == 0xffff;
1.25 +}
1.26 +
1.27 +int32_t
1.28 +FirstNon8Bit(const char16_t *str, const char16_t *end)
1.29 +{
1.30 + const uint32_t numUnicharsPerVector = 8;
1.31 + typedef Non8BitParameters<sizeof(size_t)> p;
1.32 + const size_t mask = p::mask();
1.33 + const uint32_t numUnicharsPerWord = p::numUnicharsPerWord();
1.34 + const int32_t len = end - str;
1.35 + int32_t i = 0;
1.36 +
1.37 + // Align ourselves to a 16-byte boundary, as required by _mm_load_si128
1.38 + // (i.e. MOVDQA).
1.39 + int32_t alignLen =
1.40 + std::min(len, int32_t(((-NS_PTR_TO_INT32(str)) & 0xf) / sizeof(char16_t)));
1.41 + for (; i < alignLen; i++) {
1.42 + if (str[i] > 255)
1.43 + return i;
1.44 + }
1.45 +
1.46 + // Check one XMM register (16 bytes) at a time.
1.47 + const int32_t vectWalkEnd = ((len - i) / numUnicharsPerVector) * numUnicharsPerVector;
1.48 + const uint16_t shortMask = 0xff00;
1.49 + __m128i vectmask = _mm_set1_epi16(static_cast<int16_t>(shortMask));
1.50 + for(; i < vectWalkEnd; i += numUnicharsPerVector) {
1.51 + const __m128i vect = *reinterpret_cast<const __m128i*>(str + i);
1.52 + if (!is_zero(_mm_and_si128(vect, vectmask)))
1.53 + return i;
1.54 + }
1.55 +
1.56 + // Check one word at a time.
1.57 + const int32_t wordWalkEnd = ((len - i) / numUnicharsPerWord) * numUnicharsPerWord;
1.58 + for(; i < wordWalkEnd; i += numUnicharsPerWord) {
1.59 + const size_t word = *reinterpret_cast<const size_t*>(str + i);
1.60 + if (word & mask)
1.61 + return i;
1.62 + }
1.63 +
1.64 + // Take care of the remainder one character at a time.
1.65 + for (; i < len; i++) {
1.66 + if (str[i] > 255) {
1.67 + return i;
1.68 + }
1.69 + }
1.70 +
1.71 + return -1;
1.72 +}
1.73 +
1.74 +} // namespace SSE2
1.75 +} // namespace mozilla
