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hub / github.com/ablab/spades / getHostCPUFeatures

Method getHostCPUFeatures

ext/src/llvm/Host.cpp:1363–1515  ·  view source on GitHub ↗

Source from the content-addressed store, hash-verified

1361#if defined(__i386__) || defined(_M_IX86) || \
1362 defined(__x86_64__) || defined(_M_X64)
1363bool sys::getHostCPUFeatures(StringMap<bool> &Features) {
1364 unsigned EAX = 0, EBX = 0, ECX = 0, EDX = 0;
1365 unsigned MaxLevel;
1366 union {
1367 unsigned u[3];
1368 char c[12];
1369 } text;
1370
1371 if (getX86CpuIDAndInfo(0, &MaxLevel, text.u + 0, text.u + 2, text.u + 1) ||
1372 MaxLevel < 1)
1373 return false;
1374
1375 getX86CpuIDAndInfo(1, &EAX, &EBX, &ECX, &EDX);
1376
1377 Features["cx8"] = (EDX >> 8) & 1;
1378 Features["cmov"] = (EDX >> 15) & 1;
1379 Features["mmx"] = (EDX >> 23) & 1;
1380 Features["fxsr"] = (EDX >> 24) & 1;
1381 Features["sse"] = (EDX >> 25) & 1;
1382 Features["sse2"] = (EDX >> 26) & 1;
1383
1384 Features["sse3"] = (ECX >> 0) & 1;
1385 Features["pclmul"] = (ECX >> 1) & 1;
1386 Features["ssse3"] = (ECX >> 9) & 1;
1387 Features["cx16"] = (ECX >> 13) & 1;
1388 Features["sse4.1"] = (ECX >> 19) & 1;
1389 Features["sse4.2"] = (ECX >> 20) & 1;
1390 Features["movbe"] = (ECX >> 22) & 1;
1391 Features["popcnt"] = (ECX >> 23) & 1;
1392 Features["aes"] = (ECX >> 25) & 1;
1393 Features["rdrnd"] = (ECX >> 30) & 1;
1394
1395 // If CPUID indicates support for XSAVE, XRESTORE and AVX, and XGETBV
1396 // indicates that the AVX registers will be saved and restored on context
1397 // switch, then we have full AVX support.
1398 bool HasAVXSave = ((ECX >> 27) & 1) && ((ECX >> 28) & 1) &&
1399 !getX86XCR0(&EAX, &EDX) && ((EAX & 0x6) == 0x6);
1400#if defined(__APPLE__)
1401 // Darwin lazily saves the AVX512 context on first use: trust that the OS will
1402 // save the AVX512 context if we use AVX512 instructions, even the bit is not
1403 // set right now.
1404 bool HasAVX512Save = true;
1405#else
1406 // AVX512 requires additional context to be saved by the OS.
1407 bool HasAVX512Save = HasAVXSave && ((EAX & 0xe0) == 0xe0);
1408#endif
1409
1410 Features["avx"] = HasAVXSave;
1411 Features["fma"] = ((ECX >> 12) & 1) && HasAVXSave;
1412 // Only enable XSAVE if OS has enabled support for saving YMM state.
1413 Features["xsave"] = ((ECX >> 26) & 1) && HasAVXSave;
1414 Features["f16c"] = ((ECX >> 29) & 1) && HasAVXSave;
1415
1416 unsigned MaxExtLevel;
1417 getX86CpuIDAndInfo(0x80000000, &MaxExtLevel, &EBX, &ECX, &EDX);
1418
1419 bool HasExtLeaf1 = MaxExtLevel >= 0x80000001 &&
1420 !getX86CpuIDAndInfo(0x80000001, &EAX, &EBX, &ECX, &EDX);

Callers

nothing calls this directly

Calls 9

getX86CpuIDAndInfoFunction · 0.85
getX86XCR0Function · 0.85
getX86CpuIDAndInfoExFunction · 0.85
CaseClass · 0.85
startswithMethod · 0.80
DefaultMethod · 0.80
splitMethod · 0.45
getBufferMethod · 0.45
sizeMethod · 0.45

Tested by

no test coverage detected