search for: getx86cpuidandinfo

...b/Support/Host.cpp @@ -138,6 +138,8 @@ std::string sys::getHostCPUName() { // switch, then we have full AVX support. const unsigned AVXBits = (1 << 27) | (1 << 28); bool HasAVX = ((ECX & AVXBits) == AVXBits) && OSHasAVXSupport(); + bool HasAVX2 = HasAVX && !GetX86CpuIDAndInfo(0x7, &EAX, &EBX, &ECX, &EDX) && + (EBX & 0x20); GetX86CpuIDAndInfo(0x80000001, &EAX, &EBX, &ECX, &EDX); bool Em64T = (EDX >> 29) & 0x1; @@ -258,6 +260,12 @@ std::string sys::getHostCPUName() { // versions instead...

...ds give identical assembly for Host.cpp. OK. I know the reason you cannot reproduce it, before posting the patch I've decided to check for AVX before checking AVX2, just not to cpuid AVX2 when we don't have AVX1 anyway. So the problem exists with following predicate: (1) bool HasAVX2 = !GetX86CpuIDAndInfo(0x7, &EAX, &EBX, &ECX, &EDX) && (EBX & 0x20); However it is working absolutely fine if I add "volatile": (2) volatile bool HasAVX2 = !GetX86CpuIDAndInfo(0x7, &EAX, &EBX, &ECX, &EDX) && (EBX &...

...o be not only 60, but also 63, 69 & 70 model, following changes in Linux kernel & Xen. Also set 62 as Ivy Bridge EP aka E5 v3 (which I has in my workstation). Cheers, -- Adam Detects x86 family 6 model 60, 63, 69, 70 CPU that has AVX2 CPUID leaf 7 subleaf 0 AVX2 flag as core-avx2. Port GetX86CpuIDAndInfoEx from X86MCTargetDesc to support x86 CPUID subleafs. Also detect family 6 model 62 (0x3E) Ivy Bridge EP as core-avx-i. --- lib/Support/Host.cpp | 96 ++++++++++++++++++++++++++++++++++++++--- lib/Target/X86/X86Subtarget.cpp | 7 ++- 2 files changed, 96 insertions(+), 7 deletions(-)...

Hi Adam, > * I have marked HasAVX2 as "volatile", since otherwise it gets > magically zeroed (by optimizer?) when compiling clang with latest > clang build from trunk That's far more worrying to me than not being able to detect Haswell. I can't reproduce the problem here at the moment: both debug and release builds give identical assembly for Host.cpp. I don't

I agree with Tim, you need to implement a GetCpuIDAndInfoEx function in Host.cpp and pass the correct value to ecx. Also you need to verify that 7 is a valid leaf because an invalid leaf is defined to return the highest supported leaf on that processor. So if a processor supports say leaf 6 and not leaf 7, then an access leaf 7 will return the data from leaf 6 causing unrelated bits to be

Hello, This is my first patch on this list, however I've already submitted several trough bug tracking system. Since it probably needs some review and it's not a bug I am submitting it here. The main intent of this patch is to detect "core-avx2" platform on Haswell i7 CPUs when running -march=native. Currently it detects it as generic x86_64. lib/Support/Host.cpp: * Haswell is

Hi Adam, > + bool HasAVX2 = HasAVX && !GetX86CpuIDAndInfo(0x7, &EAX, &EBX, &ECX, &EDX) && > + (EBX & 0x20); I don't think this guarantees %ecx is 0, does it? Wasn't that the entire reason the original code went wrong? Cheers. Tim.

Hi Adam, > OK. I know the reason you cannot reproduce it, before posting > the patch I've decided to check for AVX before checking AVX2, > just not to cpuid AVX2 when we don't have AVX1 anyway. I suspect it was also incompetence on my part. Given the differences I'm seeing now I can't believe there'd be *no* difference in my tests if I'd done them properly.

>> + bool HasAVX2 = HasAVX && !GetX86CpuIDAndInfo(0x7, &EAX, &EBX, &ECX, &EDX) && >> + (EBX & 0x20); > > I don't think this guarantees %ecx is 0, does it? Wasn't that the > entire reason the original code went wrong? I don’t remember really, but presuming the conclusions of the d...