/usr/include/crcutil/uint128_sse2.h is in libcrcutil-dev 1.0-4.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 | // Copyright 2010 Google Inc. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// Implements a limited set of 128-bit arithmetic operations
// (the ones that are used by CRC) using SSE2 intrinsics.
#ifndef CRCUTIL_UINT128_SSE2_H_
#define CRCUTIL_UINT128_SSE2_H_
#include "base_types.h"
#include "crc_casts.h" // Downcast, CrcFromUint64, Uint64FromCrc
#include "platform.h"
#if HAVE_SSE2
namespace crcutil {
// Specialized functions handling __m128i.
template<> __forceinline uint64 Downcast(const __m128i &value) {
#if HAVE_AMD64 && defined(__GNUC__)
// GCC 4.4.x is too smart and, instead of MOVQ, generates SSE4 PEXTRQ
// instruction when the code is compiled with -mmsse4.
// Fixed in 4.5 which generates conversion through memory (why?).
// And -- yes, it makes quite measurable difference.
uint64 temp;
asm(SSE2_MOVQ " %[i128], %[u64]\n" : [u64] "=r" (temp) : [i128] "x" (value));
return temp;
#elif HAVE_AMD64 && (!defined(_MSC_FULL_VER) || _MSC_FULL_VER > 150030729)
return static_cast<uint64>(_mm_cvtsi128_si64(value));
#else
// 64-bit CL 15.00.30729.1 -O2 generates incorrect code (tests fail).
// _mm_cvtsi128_si64() is not available on i386.
uint64 temp;
_mm_storel_epi64(reinterpret_cast<__m128i *>(&temp), value);
return temp;
#endif
}
class uint128_sse2 {
public:
uint128_sse2() {}
~uint128_sse2() {}
// Default casts to uint128_sse2 and assignment operator.
__forceinline void operator =(uint64 value) {
#if HAVE_AMD64 && defined(__GNUC__) && !GCC_VERSION_AVAILABLE(4, 5)
// Prevent generation of SSE4 pinsrq insruction when
// compiling with GCC 4.4.x with -msse4 flag.
asm(SSE2_MOVQ " %[u64], %[i128]\n" : [i128] "=x" (x_) : [u64] "r" (value));
#elif HAVE_AMD64
x_ = _mm_cvtsi64_si128(static_cast<int64>(value));
#else
x_ = _mm_loadl_epi64(reinterpret_cast<const __m128i *>(&value));
#endif
}
__forceinline uint128_sse2(uint64 x) {
*this = x;
}
__forceinline uint128_sse2(const __m128i x) : x_(x) {
}
__forceinline operator __m128i() const {
return x_;
}
__forceinline void operator =(const uint128_sse2 &x) {
x_ = x.x_;
}
// Extracts 64 less significant bits.
__forceinline uint64 to_uint64() const {
return Downcast<__m128i, uint64>(x_);
}
// Comparisons.
__forceinline bool operator ==(const uint128_sse2 &y) const {
union {
__m128i i128;
uint64 u64[2];
} t;
t.i128 = _mm_xor_si128(x_, y.x_);
return (t.u64[0] | t.u64[1]) == 0;
}
__forceinline bool operator ==(uint64 value) const {
union {
__m128i i128;
uint64 u64[2];
} t;
t.i128 = x_;
return (t.u64[0] == value && t.u64[1] == 0);
}
__forceinline bool operator !=(const uint128_sse2 &y) const {
union {
__m128i i128;
uint64 u64[2];
} t;
t.i128 = _mm_xor_si128(x_, y.x_);
return (t.u64[0] | t.u64[1]) != 0;
}
__forceinline bool operator !=(uint64 value) const {
union {
__m128i i128;
uint64 u64[2];
} t;
t.i128 = x_;
return (t.u64[0] != value || t.u64[1] != 0);
}
__forceinline bool operator <(const uint128_sse2 &y) const {
union {
__m128i i128;
uint64 u64[2];
} xx, yy;
xx.i128 = x_;
yy.i128 = y.x_;
return (xx.u64[0] < yy.u64[0] ||
(xx.u64[0] == yy.u64[0] && xx.u64[1] < yy.u64[1]));
}
// Bitwise logic operators.
__forceinline uint128_sse2 operator ^(const uint128_sse2 &y) const {
return _mm_xor_si128(x_, y.x_);
}
__forceinline uint128_sse2 operator &(const uint128_sse2 &y) const {
return _mm_and_si128(x_, y.x_);
}
__forceinline uint128_sse2 operator |(const uint128_sse2 &y) const {
return _mm_or_si128(x_, y.x_);
}
__forceinline void operator ^=(const uint128_sse2 &y) {
*this = *this ^ y.x_;
}
__forceinline void operator &=(const uint128_sse2 &y) {
*this = *this & y.x_;
}
__forceinline void operator |=(const uint128_sse2 &y) {
*this = *this | y.x_;
}
// Arithmetic operators.
__forceinline uint128_sse2 operator +(uint64 y) const {
union {
__m128i i128;
uint64 u64[2];
} temp;
temp.i128 = x_;
// a + b >= 2**64 iff
// a + b > (2**64 - 1) iff
// a > (2**64 - 1) - b iff
// a > ~b
if (temp.u64[0] > ~y) {
temp.u64[1] += 1;
}
temp.u64[0] += y;
return temp.i128;
}
__forceinline void operator +=(uint64 x) {
*this = *this + x;
}
__forceinline uint128_sse2 operator -(uint64 y) const {
union {
__m128i i128;
uint64 u64[2];
} temp;
temp.i128 = x_;
if (temp.u64[0] < y) {
temp.u64[1] -= 1;
}
temp.u64[0] -= y;
return temp.i128;
}
__forceinline void operator -=(uint64 x) {
*this = *this - x;
}
// Bitwise logical shifts.
__forceinline uint128_sse2 operator >>(const int bits) const {
if (bits == 8) {
return _mm_srli_si128(x_, 1);
} else if (bits == 16) {
return _mm_srli_si128(x_, 2);
} else if (bits == 32) {
return _mm_srli_si128(x_, 4);
} else if (bits == 64) {
return _mm_srli_si128(x_, 8);
} else {
return long_shift_right(bits);
}
}
__forceinline uint128_sse2 operator >>(const size_t bits) const {
return *this >> static_cast<int>(bits);
}
__forceinline void operator >>=(const int bits) {
*this = *this >> bits;
}
__forceinline void operator >>=(const size_t bits) {
*this = *this >> static_cast<int>(bits);
}
__forceinline uint128_sse2 operator <<(int bits) const {
if (bits == 8) {
return _mm_slli_si128(x_, 1);
} else if (bits == 16) {
return _mm_slli_si128(x_, 2);
} else if (bits == 32) {
return _mm_slli_si128(x_, 4);
} else if (bits == 64) {
return _mm_slli_si128(x_, 8);
} else {
return long_shift_left(bits);
}
}
__forceinline uint128_sse2 operator <<(size_t bits) const {
return *this << static_cast<int>(bits);
}
__forceinline void operator <<=(int bits) {
*this = *this << bits;
}
__forceinline void operator <<=(size_t bits) {
*this = *this << static_cast<int>(bits);
}
protected:
__forceinline uint128_sse2 long_shift_right(int bits) const {
union {
__m128i i128;
uint64 u64[2];
} x;
x.i128 = x_;
for (; bits > 0; --bits) {
x.u64[0] >>= 1;
if (x.u64[1] & 1) {
x.u64[0] |= static_cast<uint64>(1) << 63;
}
x.u64[1] >>= 1;
}
return x.i128;
}
__forceinline uint128_sse2 long_shift_left(int bits) const {
union {
__m128i i128;
int64 i64[2];
} x;
x.i128 = x_;
for (; bits > 0; --bits) {
x.i64[1] <<= 1;
if (x.i64[0] < 0) {
x.i64[1] |= 1;
}
x.i64[0] <<= 1;
}
return x.i128;
}
__m128i x_;
} GCC_ALIGN_ATTRIBUTE(16);
// Specialized versions.
template<> __forceinline uint64 Downcast(const uint128_sse2 &x) {
return x.to_uint64();
}
template<> __forceinline uint32 Downcast(const uint128_sse2 &x) {
return static_cast<uint32>(x.to_uint64());
}
template<> __forceinline uint16 Downcast(const uint128_sse2 &x) {
return static_cast<uint16>(x.to_uint64());
}
template<> __forceinline uint8 Downcast(const uint128_sse2 &x) {
return static_cast<uint8>(x.to_uint64());
}
template<> __forceinline uint128_sse2 CrcFromUint64(uint64 lo, uint64 hi) {
union {
__m128i i128;
uint64 u64[2];
} temp;
temp.u64[0] = lo;
temp.u64[1] = hi;
return temp.i128;
}
template<> __forceinline void Uint64FromCrc(const uint128_sse2 &crc,
uint64 *lo, uint64 *hi) {
union {
__m128i i128;
uint64 u64[2];
} temp;
temp.i128 = crc;
*lo = temp.u64[0];
*hi = temp.u64[1];
}
} // namespace crcutil
#endif // HAVE_SSE2
#endif // CRCUTIL_UINT128_SSE2_H_
|