intl/uconv/src/nsUTF8ToUnicodeSSE2.cpp@97036ab72558 (annotated)
intl/uconv/src/nsUTF8ToUnicodeSSE2.cpp
Tue, 06 Jan 2015 21:39:09 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Tue, 06 Jan 2015 21:39:09 +0100
- branch
- TOR_BUG_9701
- changeset 8
- 97036ab72558
- permissions
- -rw-r--r--
Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.
| michael@0 | 1 | /* This Source Code Form is subject to the terms of the Mozilla Public |
| michael@0 | 2 | * License, v. 2.0. If a copy of the MPL was not distributed with this |
| michael@0 | 3 | * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ |
| michael@0 | 4 | |
| michael@0 | 5 | // This file should only be compiled if you're on x86 or x86_64. Additionally, |
| michael@0 | 6 | // you'll need to compile this file with -msse2 if you're using gcc. |
| michael@0 | 7 | |
| michael@0 | 8 | #include <emmintrin.h> |
| michael@0 | 9 | #include "nscore.h" |
| michael@0 | 10 | |
| michael@0 | 11 | namespace mozilla { |
| michael@0 | 12 | namespace SSE2 { |
| michael@0 | 13 | |
| michael@0 | 14 | void |
| michael@0 | 15 | Convert_ascii_run(const char *&src, |
| michael@0 | 16 | char16_t *&dst, |
| michael@0 | 17 | int32_t len) |
| michael@0 | 18 | { |
| michael@0 | 19 | if (len > 15) { |
| michael@0 | 20 | __m128i in, out1, out2; |
| michael@0 | 21 | __m128d *outp1, *outp2; |
| michael@0 | 22 | __m128i zeroes; |
| michael@0 | 23 | uint32_t offset; |
| michael@0 | 24 | |
| michael@0 | 25 | // align input to 16 bytes |
| michael@0 | 26 | while ((NS_PTR_TO_UINT32(src) & 15) && len > 0) { |
| michael@0 | 27 | if (*src & 0x80U) |
| michael@0 | 28 | return; |
| michael@0 | 29 | *dst++ = (char16_t) *src++; |
| michael@0 | 30 | len--; |
| michael@0 | 31 | } |
| michael@0 | 32 | |
| michael@0 | 33 | zeroes = _mm_setzero_si128(); |
| michael@0 | 34 | |
| michael@0 | 35 | offset = NS_PTR_TO_UINT32(dst) & 15; |
| michael@0 | 36 | |
| michael@0 | 37 | // Note: all these inner loops have to break, not return; we need |
| michael@0 | 38 | // to let the single-char loop below catch any leftover |
| michael@0 | 39 | // byte-at-a-time ASCII chars, since this function must consume |
| michael@0 | 40 | // all available ASCII chars before it returns |
| michael@0 | 41 | |
| michael@0 | 42 | if (offset == 0) { |
| michael@0 | 43 | while (len > 15) { |
| michael@0 | 44 | in = _mm_load_si128((__m128i *) src); |
| michael@0 | 45 | if (_mm_movemask_epi8(in)) |
| michael@0 | 46 | break; |
| michael@0 | 47 | out1 = _mm_unpacklo_epi8(in, zeroes); |
| michael@0 | 48 | out2 = _mm_unpackhi_epi8(in, zeroes); |
| michael@0 | 49 | _mm_stream_si128((__m128i *) dst, out1); |
| michael@0 | 50 | _mm_stream_si128((__m128i *) (dst + 8), out2); |
| michael@0 | 51 | dst += 16; |
| michael@0 | 52 | src += 16; |
| michael@0 | 53 | len -= 16; |
| michael@0 | 54 | } |
| michael@0 | 55 | } else if (offset == 8) { |
| michael@0 | 56 | outp1 = (__m128d *) &out1; |
| michael@0 | 57 | outp2 = (__m128d *) &out2; |
| michael@0 | 58 | while (len > 15) { |
| michael@0 | 59 | in = _mm_load_si128((__m128i *) src); |
| michael@0 | 60 | if (_mm_movemask_epi8(in)) |
| michael@0 | 61 | break; |
| michael@0 | 62 | out1 = _mm_unpacklo_epi8(in, zeroes); |
| michael@0 | 63 | out2 = _mm_unpackhi_epi8(in, zeroes); |
| michael@0 | 64 | _mm_storel_epi64((__m128i *) dst, out1); |
| michael@0 | 65 | _mm_storel_epi64((__m128i *) (dst + 8), out2); |
| michael@0 | 66 | _mm_storeh_pd((double *) (dst + 4), *outp1); |
| michael@0 | 67 | _mm_storeh_pd((double *) (dst + 12), *outp2); |
| michael@0 | 68 | src += 16; |
| michael@0 | 69 | dst += 16; |
| michael@0 | 70 | len -= 16; |
| michael@0 | 71 | } |
| michael@0 | 72 | } else { |
| michael@0 | 73 | while (len > 15) { |
| michael@0 | 74 | in = _mm_load_si128((__m128i *) src); |
| michael@0 | 75 | if (_mm_movemask_epi8(in)) |
| michael@0 | 76 | break; |
| michael@0 | 77 | out1 = _mm_unpacklo_epi8(in, zeroes); |
| michael@0 | 78 | out2 = _mm_unpackhi_epi8(in, zeroes); |
| michael@0 | 79 | _mm_storeu_si128((__m128i *) dst, out1); |
| michael@0 | 80 | _mm_storeu_si128((__m128i *) (dst + 8), out2); |
| michael@0 | 81 | src += 16; |
| michael@0 | 82 | dst += 16; |
| michael@0 | 83 | len -= 16; |
| michael@0 | 84 | } |
| michael@0 | 85 | } |
| michael@0 | 86 | } |
| michael@0 | 87 | |
| michael@0 | 88 | // finish off a byte at a time |
| michael@0 | 89 | |
| michael@0 | 90 | while (len-- > 0 && (*src & 0x80U) == 0) { |
| michael@0 | 91 | *dst++ = (char16_t) *src++; |
| michael@0 | 92 | } |
| michael@0 | 93 | } |
| michael@0 | 94 | |
| michael@0 | 95 | } // namespace SSE2 |
| michael@0 | 96 | } // namespace mozilla |
