mozglue/misc/SSE.h

   1 /* vim: set shiftwidth=2 tabstop=8 autoindent cindent expandtab: */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 /* compile-time and runtime tests for whether to use SSE instructions */
   7
   8 #ifndef mozilla_SSE_h_
   9 #define mozilla_SSE_h_
  10
  11 // for definition of MFBT_DATA
  12 #include "mozilla/Types.h"
  13
  14 /**
  15  * The public interface of this header consists of a set of macros and
  16  * functions for Intel CPU features.
  17  *
  18  * DETECTING ISA EXTENSIONS
  19  * ========================
  20  *
  21  * This header provides the following functions for determining whether the
  22  * current CPU supports a particular instruction set extension:
  23  *
  24  *    mozilla::supports_mmx
  25  *    mozilla::supports_sse
  26  *    mozilla::supports_sse2
  27  *    mozilla::supports_sse3
  28  *    mozilla::supports_ssse3
  29  *    mozilla::supports_sse4a
  30  *    mozilla::supports_sse4_1
  31  *    mozilla::supports_sse4_2
  32  *    mozilla::supports_avx
  33  *    mozilla::supports_avx2
  34  *    mozilla::supports_aes
  35  *    mozilla::has_constant_tsc
  36  *
  37  * If you're writing code using inline assembly, you should guard it with a
  38  * call to one of these functions.  For instance:
  39  *
  40  *   if (mozilla::supports_sse2()) {
  41  *     asm(" ... ");
  42  *   }
  43  *   else {
  44  *     ...
  45  *   }
  46  *
  47  * Note that these functions depend on cpuid intrinsics only available in gcc
  48  * 4.3 or later and MSVC 8.0 (Visual C++ 2005) or later, so they return false
  49  * in older compilers.  (This could be fixed by replacing the code with inline
  50  * assembly.)
  51  *
  52  *
  53  * USING INTRINSICS
  54  * ================
  55  *
  56  * This header also provides support for coding using CPU intrinsics.
  57  *
  58  * For each mozilla::supports_abc function, we define a MOZILLA_MAY_SUPPORT_ABC
  59  * macro which indicates that the target/compiler combination we're using is
  60  * compatible with the ABC extension.  For instance, x86_64 with MSVC 2003 is
  61  * compatible with SSE2 but not SSE3, since although there exist x86_64 CPUs
  62  * with SSE3 support, MSVC 2003 only supports through SSE2.
  63  *
  64  * Until gcc fixes #pragma target [1] [2] or our x86 builds require SSE2,
  65  * you'll need to separate code using intrinsics into a file separate from your
  66  * regular code.  Here's the recommended pattern:
  67  *
  68  *  #ifdef MOZILLA_MAY_SUPPORT_ABC
  69  *    namespace mozilla {
  70  *      namespace ABC {
  71  *        void foo();
  72  *      }
  73  *    }
  74  *  #endif
  75  *
  76  *  void foo() {
  77  *    #ifdef MOZILLA_MAY_SUPPORT_ABC
  78  *      if (mozilla::supports_abc()) {
  79  *        mozilla::ABC::foo(); // in a separate file
  80  *        return;
  81  *      }
  82  *    #endif
  83  *
  84  *    foo_unvectorized();
  85  *  }
  86  *
  87  * You'll need to define mozilla::ABC::foo() in a separate file and add the
  88  * -mabc flag when using gcc.
  89  *
  90  * [1] http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39787 and
  91  * [2] http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41201 being fixed.
  92  *
  93  */
  94
  95 #if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
  96
  97 #  ifdef __MMX__
  98 // It's ok to use MMX instructions based on the -march option (or
  99 // the default for x86_64 or for Intel Mac).
 100 #    define MOZILLA_PRESUME_MMX 1
 101 #  endif
 102 #  ifdef __SSE__
 103 // It's ok to use SSE instructions based on the -march option (or
 104 // the default for x86_64 or for Intel Mac).
 105 #    define MOZILLA_PRESUME_SSE 1
 106 #  endif
 107 #  ifdef __SSE2__
 108 // It's ok to use SSE2 instructions based on the -march option (or
 109 // the default for x86_64 or for Intel Mac).
 110 #    define MOZILLA_PRESUME_SSE2 1
 111 #  endif
 112 #  ifdef __SSE3__
 113 // It's ok to use SSE3 instructions based on the -march option (or the
 114 // default for Intel Mac).
 115 #    define MOZILLA_PRESUME_SSE3 1
 116 #  endif
 117 #  ifdef __SSSE3__
 118 // It's ok to use SSSE3 instructions based on the -march option.
 119 #    define MOZILLA_PRESUME_SSSE3 1
 120 #  endif
 121 #  ifdef __SSE4A__
 122 // It's ok to use SSE4A instructions based on the -march option.
 123 #    define MOZILLA_PRESUME_SSE4A 1
 124 #  endif
 125 #  ifdef __SSE4_1__
 126 // It's ok to use SSE4.1 instructions based on the -march option.
 127 #    define MOZILLA_PRESUME_SSE4_1 1
 128 #  endif
 129 #  ifdef __SSE4_2__
 130 // It's ok to use SSE4.2 instructions based on the -march option.
 131 #    define MOZILLA_PRESUME_SSE4_2 1
 132 #  endif
 133 #  ifdef __AVX__
 134 // It's ok to use AVX instructions based on the -march option.
 135 #    define MOZILLA_PRESUME_AVX 1
 136 #  endif
 137 #  ifdef __AVX2__
 138 // It's ok to use AVX instructions based on the -march option.
 139 #    define MOZILLA_PRESUME_AVX2 1
 140 #  endif
 141 #  ifdef __AES__
 142 // It's ok to use AES instructions based on the -march option.
 143 #    define MOZILLA_PRESUME_AES 1
 144 #  endif
 145
 146 #  ifdef HAVE_CPUID_H
 147 #    define MOZILLA_SSE_HAVE_CPUID_DETECTION
 148 #  endif
 149
 150 #elif defined(_MSC_VER) && (defined(_M_IX86) || defined(_M_AMD64))
 151
 152 #  define MOZILLA_SSE_HAVE_CPUID_DETECTION
 153
 154 #  if defined(_M_IX86_FP)
 155
 156 #    if _M_IX86_FP >= 1
 157 // It's ok to use SSE instructions based on the /arch option
 158 #      define MOZILLA_PRESUME_SSE
 159 #    endif
 160 #    if _M_IX86_FP >= 2
 161 // It's ok to use SSE2 instructions based on the /arch option
 162 #      define MOZILLA_PRESUME_SSE2
 163 #    endif
 164
 165 #  elif defined(_M_AMD64)
 166 // MSVC for AMD64 doesn't support MMX, so don't presume it here.
 167
 168 // SSE is always available on AMD64.
 169 #    define MOZILLA_PRESUME_SSE
 170 // SSE2 is always available on AMD64.
 171 #    define MOZILLA_PRESUME_SSE2
 172 #  endif
 173
 174 #elif defined(__SUNPRO_CC) && (defined(__i386) || defined(__x86_64__))
 175 // Sun Studio on x86 or amd64
 176
 177 #  define MOZILLA_SSE_HAVE_CPUID_DETECTION
 178
 179 #  if defined(__x86_64__)
 180 // MMX is always available on AMD64.
 181 #    define MOZILLA_PRESUME_MMX
 182 // SSE is always available on AMD64.
 183 #    define MOZILLA_PRESUME_SSE
 184 // SSE2 is always available on AMD64.
 185 #    define MOZILLA_PRESUME_SSE2
 186 #  endif
 187
 188 #endif
 189
 190 namespace mozilla {
 191
 192 namespace sse_private {
 193 #if defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
 194 #  if !defined(MOZILLA_PRESUME_MMX)
 195 extern bool MFBT_DATA mmx_enabled;
 196 #  endif
 197 #  if !defined(MOZILLA_PRESUME_SSE)
 198 extern bool MFBT_DATA sse_enabled;
 199 #  endif
 200 #  if !defined(MOZILLA_PRESUME_SSE2)
 201 extern bool MFBT_DATA sse2_enabled;
 202 #  endif
 203 #  if !defined(MOZILLA_PRESUME_SSE3)
 204 extern bool MFBT_DATA sse3_enabled;
 205 #  endif
 206 #  if !defined(MOZILLA_PRESUME_SSSE3)
 207 extern bool MFBT_DATA ssse3_enabled;
 208 #  endif
 209 #  if !defined(MOZILLA_PRESUME_SSE4A)
 210 extern bool MFBT_DATA sse4a_enabled;
 211 #  endif
 212 #  if !defined(MOZILLA_PRESUME_SSE4_1)
 213 extern bool MFBT_DATA sse4_1_enabled;
 214 #  endif
 215 #  if !defined(MOZILLA_PRESUME_SSE4_2)
 216 extern bool MFBT_DATA sse4_2_enabled;
 217 #  endif
 218 #  if !defined(MOZILLA_PRESUME_FMA3)
 219 extern bool MFBT_DATA fma3_enabled;
 220 #  endif
 221 #  if !defined(MOZILLA_PRESUME_AVX)
 222 extern bool MFBT_DATA avx_enabled;
 223 #  endif
 224 #  if !defined(MOZILLA_PRESUME_AVX2)
 225 extern bool MFBT_DATA avx2_enabled;
 226 #  endif
 227 #  if !defined(MOZILLA_PRESUME_AES)
 228 extern bool MFBT_DATA aes_enabled;
 229 #  endif
 230 extern bool MFBT_DATA has_constant_tsc;
 231
 232 #endif
 233 }  // namespace sse_private
 234
 235 #ifdef HAVE_CPUID_H
 236 MOZ_EXPORT uint64_t xgetbv(uint32_t xcr);
 237 #endif
 238
 239 #if defined(MOZILLA_PRESUME_MMX)
 240 #  define MOZILLA_MAY_SUPPORT_MMX 1
 241 inline bool supports_mmx() { return true; }
 242 #elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
 243 #  if !(defined(_MSC_VER) && defined(_M_AMD64))
 244 // Define MOZILLA_MAY_SUPPORT_MMX only if we're not on MSVC for
 245 // AMD64, since that compiler doesn't support MMX.
 246 #    define MOZILLA_MAY_SUPPORT_MMX 1
 247 #  endif
 248 inline bool supports_mmx() { return sse_private::mmx_enabled; }
 249 #else
 250 inline bool supports_mmx() { return false; }
 251 #endif
 252
 253 #if defined(MOZILLA_PRESUME_SSE)
 254 #  define MOZILLA_MAY_SUPPORT_SSE 1
 255 inline bool supports_sse() { return true; }
 256 #elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
 257 #  define MOZILLA_MAY_SUPPORT_SSE 1
 258 inline bool supports_sse() { return sse_private::sse_enabled; }
 259 #else
 260 inline bool supports_sse() { return false; }
 261 #endif
 262
 263 #if defined(MOZILLA_PRESUME_SSE2)
 264 #  define MOZILLA_MAY_SUPPORT_SSE2 1
 265 inline bool supports_sse2() { return true; }
 266 #elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
 267 #  define MOZILLA_MAY_SUPPORT_SSE2 1
 268 inline bool supports_sse2() { return sse_private::sse2_enabled; }
 269 #else
 270 inline bool supports_sse2() { return false; }
 271 #endif
 272
 273 #if defined(MOZILLA_PRESUME_SSE3)
 274 #  define MOZILLA_MAY_SUPPORT_SSE3 1
 275 inline bool supports_sse3() { return true; }
 276 #elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
 277 #  define MOZILLA_MAY_SUPPORT_SSE3 1
 278 inline bool supports_sse3() { return sse_private::sse3_enabled; }
 279 #else
 280 inline bool supports_sse3() { return false; }
 281 #endif
 282
 283 #if defined(MOZILLA_PRESUME_SSSE3)
 284 #  define MOZILLA_MAY_SUPPORT_SSSE3 1
 285 inline bool supports_ssse3() { return true; }
 286 #elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
 287 #  define MOZILLA_MAY_SUPPORT_SSSE3 1
 288 inline bool supports_ssse3() { return sse_private::ssse3_enabled; }
 289 #else
 290 inline bool supports_ssse3() { return false; }
 291 #endif
 292
 293 #if defined(MOZILLA_PRESUME_SSE4A)
 294 #  define MOZILLA_MAY_SUPPORT_SSE4A 1
 295 inline bool supports_sse4a() { return true; }
 296 #elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
 297 #  define MOZILLA_MAY_SUPPORT_SSE4A 1
 298 inline bool supports_sse4a() { return sse_private::sse4a_enabled; }
 299 #else
 300 inline bool supports_sse4a() { return false; }
 301 #endif
 302
 303 #if defined(MOZILLA_PRESUME_SSE4_1)
 304 #  define MOZILLA_MAY_SUPPORT_SSE4_1 1
 305 inline bool supports_sse4_1() { return true; }
 306 #elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
 307 #  define MOZILLA_MAY_SUPPORT_SSE4_1 1
 308 inline bool supports_sse4_1() { return sse_private::sse4_1_enabled; }
 309 #else
 310 inline bool supports_sse4_1() { return false; }
 311 #endif
 312
 313 #if defined(MOZILLA_PRESUME_SSE4_2)
 314 #  define MOZILLA_MAY_SUPPORT_SSE4_2 1
 315 inline bool supports_sse4_2() { return true; }
 316 #elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
 317 #  define MOZILLA_MAY_SUPPORT_SSE4_2 1
 318 inline bool supports_sse4_2() { return sse_private::sse4_2_enabled; }
 319 #else
 320 inline bool supports_sse4_2() { return false; }
 321 #endif
 322
 323 #if defined(MOZILLA_PRESUME_FMA3)
 324 #  define MOZILLA_MAY_SUPPORT_FMA3 1
 325 inline bool supports_fma3() { return true; }
 326 #elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
 327 #  define MOZILLA_MAY_SUPPORT_FMA3 1
 328 inline bool supports_fma3() { return sse_private::fma3_enabled; }
 329 #else
 330 inline bool supports_fma3() { return false; }
 331 #endif
 332
 333 #if defined(MOZILLA_PRESUME_AVX)
 334 #  define MOZILLA_MAY_SUPPORT_AVX 1
 335 inline bool supports_avx() { return true; }
 336 #elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
 337 #  define MOZILLA_MAY_SUPPORT_AVX 1
 338 inline bool supports_avx() { return sse_private::avx_enabled; }
 339 #else
 340 inline bool supports_avx() { return false; }
 341 #endif
 342
 343 #if defined(MOZILLA_PRESUME_AVX2)
 344 #  define MOZILLA_MAY_SUPPORT_AVX2 1
 345 inline bool supports_avx2() { return true; }
 346 #elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
 347 #  define MOZILLA_MAY_SUPPORT_AVX2 1
 348 inline bool supports_avx2() { return sse_private::avx2_enabled; }
 349 #else
 350 inline bool supports_avx2() { return false; }
 351 #endif
 352
 353 #if defined(MOZILLA_PRESUME_AES)
 354 #  define MOZILLA_MAY_SUPPORT_AES 1
 355 inline bool supports_aes() { return true; }
 356 #elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
 357 #  define MOZILLA_MAY_SUPPORT_AES 1
 358 inline bool supports_aes() { return sse_private::aes_enabled; }
 359 #else
 360 inline bool supports_aes() { return false; }
 361 #endif
 362
 363 #ifdef MOZILLA_SSE_HAVE_CPUID_DETECTION
 364 inline bool has_constant_tsc() { return sse_private::has_constant_tsc; }
 365 #else
 366 inline bool has_constant_tsc() { return false; }
 367 #endif
 368
 369 }  // namespace mozilla
 370
 371 #endif /* !defined(mozilla_SSE_h_) */