diff options
Diffstat (limited to 'contrib/llvm/lib/Target/X86/X86Subtarget.cpp')
| -rw-r--r-- | contrib/llvm/lib/Target/X86/X86Subtarget.cpp | 25 |
1 files changed, 24 insertions, 1 deletions
diff --git a/contrib/llvm/lib/Target/X86/X86Subtarget.cpp b/contrib/llvm/lib/Target/X86/X86Subtarget.cpp index 14619b6..74da2a9 100644 --- a/contrib/llvm/lib/Target/X86/X86Subtarget.cpp +++ b/contrib/llvm/lib/Target/X86/X86Subtarget.cpp @@ -170,6 +170,26 @@ bool X86Subtarget::IsLegalToCallImmediateAddr(const TargetMachine &TM) const { return isTargetELF() || TM.getRelocationModel() == Reloc::Static; } +static bool OSHasAVXSupport() { +#if defined(i386) || defined(__i386__) || defined(__x86__) || defined(_M_IX86)\ + || defined(__x86_64__) || defined(_M_AMD64) || defined (_M_X64) +#if defined(__GNUC__) + // Check xgetbv; this uses a .byte sequence instead of the instruction + // directly because older assemblers do not include support for xgetbv and + // there is no easy way to conditionally compile based on the assembler used. + int rEAX, rEDX; + __asm__ (".byte 0x0f, 0x01, 0xd0" : "=a" (rEAX), "=d" (rEDX) : "c" (0)); +#elif defined(_MSC_FULL_VER) && defined(_XCR_XFEATURE_ENABLED_MASK) + unsigned long long rEAX = _xgetbv(_XCR_XFEATURE_ENABLED_MASK); +#else + int rEAX = 0; // Ensures we return false +#endif + return (rEAX & 6) == 6; +#else + return false; +#endif +} + void X86Subtarget::AutoDetectSubtargetFeatures() { unsigned EAX = 0, EBX = 0, ECX = 0, EDX = 0; unsigned MaxLevel; @@ -192,7 +212,9 @@ void X86Subtarget::AutoDetectSubtargetFeatures() { if ((ECX >> 9) & 1) { X86SSELevel = SSSE3; ToggleFeature(X86::FeatureSSSE3);} if ((ECX >> 19) & 1) { X86SSELevel = SSE41; ToggleFeature(X86::FeatureSSE41);} if ((ECX >> 20) & 1) { X86SSELevel = SSE42; ToggleFeature(X86::FeatureSSE42);} - if ((ECX >> 28) & 1) { X86SSELevel = AVX; ToggleFeature(X86::FeatureAVX); } + if (((ECX >> 27) & 1) && ((ECX >> 28) & 1) && OSHasAVXSupport()) { + X86SSELevel = AVX; ToggleFeature(X86::FeatureAVX); + } bool IsIntel = memcmp(text.c, "GenuineIntel", 12) == 0; bool IsAMD = !IsIntel && memcmp(text.c, "AuthenticAMD", 12) == 0; @@ -467,6 +489,7 @@ void X86Subtarget::initializeEnvironment() { PostRAScheduler = false; PadShortFunctions = false; CallRegIndirect = false; + LEAUsesAG = false; stackAlignment = 4; // FIXME: this is a known good value for Yonah. How about others? MaxInlineSizeThreshold = 128; |
