mirror of
https://github.com/mozilla/gecko-dev.git
synced 2024-11-05 00:25:27 +00:00
75 lines
2.2 KiB
C++
75 lines
2.2 KiB
C++
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
|
|
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
|
|
/* This Source Code Form is subject to the terms of the Mozilla Public
|
|
* License, v. 2.0. If a copy of the MPL was not distributed with this
|
|
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
|
|
|
|
// This file should only be compiled if you're on x86 or x86_64. Additionally,
|
|
// you'll need to compile this file with -msse2 if you're using gcc.
|
|
|
|
#include <emmintrin.h>
|
|
#include "nscore.h"
|
|
#include "nsAlgorithm.h"
|
|
#include "nsTextFragmentImpl.h"
|
|
#include <algorithm>
|
|
|
|
namespace mozilla {
|
|
namespace SSE2 {
|
|
|
|
static inline bool
|
|
is_zero (__m128i x)
|
|
{
|
|
return
|
|
_mm_movemask_epi8(_mm_cmpeq_epi8(x, _mm_setzero_si128())) == 0xffff;
|
|
}
|
|
|
|
int32_t
|
|
FirstNon8Bit(const char16_t *str, const char16_t *end)
|
|
{
|
|
const uint32_t numUnicharsPerVector = 8;
|
|
typedef Non8BitParameters<sizeof(size_t)> p;
|
|
const size_t mask = p::mask();
|
|
const uint32_t numUnicharsPerWord = p::numUnicharsPerWord();
|
|
const int32_t len = end - str;
|
|
int32_t i = 0;
|
|
|
|
// Align ourselves to a 16-byte boundary, as required by _mm_load_si128
|
|
// (i.e. MOVDQA).
|
|
int32_t alignLen =
|
|
std::min(len, int32_t(((-NS_PTR_TO_INT32(str)) & 0xf) / sizeof(char16_t)));
|
|
for (; i < alignLen; i++) {
|
|
if (str[i] > 255)
|
|
return i;
|
|
}
|
|
|
|
// Check one XMM register (16 bytes) at a time.
|
|
const int32_t vectWalkEnd = ((len - i) / numUnicharsPerVector) * numUnicharsPerVector;
|
|
const uint16_t shortMask = 0xff00;
|
|
__m128i vectmask = _mm_set1_epi16(static_cast<int16_t>(shortMask));
|
|
for(; i < vectWalkEnd; i += numUnicharsPerVector) {
|
|
const __m128i vect = *reinterpret_cast<const __m128i*>(str + i);
|
|
if (!is_zero(_mm_and_si128(vect, vectmask)))
|
|
return i;
|
|
}
|
|
|
|
// Check one word at a time.
|
|
const int32_t wordWalkEnd = ((len - i) / numUnicharsPerWord) * numUnicharsPerWord;
|
|
for(; i < wordWalkEnd; i += numUnicharsPerWord) {
|
|
const size_t word = *reinterpret_cast<const size_t*>(str + i);
|
|
if (word & mask)
|
|
return i;
|
|
}
|
|
|
|
// Take care of the remainder one character at a time.
|
|
for (; i < len; i++) {
|
|
if (str[i] > 255) {
|
|
return i;
|
|
}
|
|
}
|
|
|
|
return -1;
|
|
}
|
|
|
|
} // namespace SSE2
|
|
} // namespace mozilla
|