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| author | Carlos O'Donell <carlos_odonell@mentor.com> | 2012-05-16 20:14:24 -0700 |
|---|---|---|
| committer | Carlos O'Donell <carlos_odonell@mentor.com> | 2012-05-17 06:59:28 -0700 |
| commit | 1a0994f5356214e8af8a1c1cc33fbf74a7ac8993 (patch) | |
| tree | 99ce1f919a2509868a71f4262f055b5eec9accb0 /sysdeps/x86_64/multiarch/init-arch.c | |
| parent | 0af797def371ceb4f05586d7bcd25841653d2082 (diff) | |
| download | glibc-1a0994f5356214e8af8a1c1cc33fbf74a7ac8993.tar.gz glibc-1a0994f5356214e8af8a1c1cc33fbf74a7ac8993.tar.xz glibc-1a0994f5356214e8af8a1c1cc33fbf74a7ac8993.zip | |
BZ#14059: Fix AVX and FMA4 detection.
Fix AVX and FMA4 detection by following the guidelines set out by Intel and AMD for detecting these features.
Diffstat (limited to 'sysdeps/x86_64/multiarch/init-arch.c')
| -rw-r--r-- | sysdeps/x86_64/multiarch/init-arch.c | 27 |
1 files changed, 17 insertions, 10 deletions
diff --git a/sysdeps/x86_64/multiarch/init-arch.c b/sysdeps/x86_64/multiarch/init-arch.c index 80527ec59d..fb44dcfcf6 100644 --- a/sysdeps/x86_64/multiarch/init-arch.c +++ b/sysdeps/x86_64/multiarch/init-arch.c @@ -1,6 +1,6 @@ /* Initialize CPU feature data. This file is part of the GNU C Library. - Copyright (C) 2008, 2009, 2010, 2011, 2012 Free Software Foundation, Inc. + Copyright (C) 2008-2012 Free Software Foundation, Inc. Contributed by Ulrich Drepper <drepper@redhat.com>. The GNU C Library is free software; you can redistribute it and/or @@ -143,16 +143,23 @@ __init_cpu_features (void) else kind = arch_kind_other; - if (__cpu_features.cpuid[COMMON_CPUID_INDEX_1].ecx & bit_AVX) + /* Can we call xgetbv? */ + if (CPUID_OSXSAVE) { - /* Reset the AVX bit in case OSXSAVE is disabled. */ - if ((__cpu_features.cpuid[COMMON_CPUID_INDEX_1].ecx & bit_OSXSAVE) != 0 - && ({ unsigned int xcrlow; - unsigned int xcrhigh; - asm ("xgetbv" - : "=a" (xcrlow), "=d" (xcrhigh) : "c" (0)); - (xcrlow & 6) == 6; })) - __cpu_features.feature[index_YMM_Usable] |= bit_YMM_Usable; + unsigned int xcrlow; + unsigned int xcrhigh; + asm ("xgetbv" : "=a" (xcrlow), "=d" (xcrhigh) : "c" (0)); + /* Is YMM and XMM state usable? */ + if ((xcrlow & (bit_YMM_state | bit_XMM_state)) == + (bit_YMM_state | bit_XMM_state)) + { + /* Determine if AVX is usable. */ + if (CPUID_AVX) + __cpu_features.feature[index_AVX_Usable] |= bit_AVX_Usable; + /* Determine if FMA4 is usable. */ + if (CPUID_FMA4) + __cpu_features.feature[index_FMA4_Usable] |= bit_FMA4_Usable; + } } __cpu_features.family = family; |