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| author | Birk Magnussen <birk.magnussen@googlemail.com> | 2019-10-17 00:11:26 +0200 |
|---|---|---|
| committer | Birk Magnussen <birk.magnussen@googlemail.com> | 2019-10-17 13:16:54 +0200 |
| commit | 602d25ec4344f96031ce1043c15490e79438c1bc (patch) | |
| tree | 33ea45e4fcf9f671f7ce86b574a110ed6f394e0d /vpx_ports | |
| parent | 2be0ee5f05b3dc0782626b8b10894d5d920bcb96 (diff) | |
| download | libvpx-602d25ec4344f96031ce1043c15490e79438c1bc.tar libvpx-602d25ec4344f96031ce1043c15490e79438c1bc.tar.gz libvpx-602d25ec4344f96031ce1043c15490e79438c1bc.tar.bz2 libvpx-602d25ec4344f96031ce1043c15490e79438c1bc.zip | |
Fix AVX-512 capability detection
When Checking for AVX Support, only the CPU's Capabilities and YMM
Register support by the OS were queried. In case of AVX-512, that is
insufficient, and ZMM Register support by the OS needs querying,
otherwise the OS will raise an Illegal Operation Exception if the CPU
is capable of AVX-512 but the OS is not.
Change-Id: I3444b19156d5743841de96cecbdaac19cc3f2b3f
Diffstat (limited to 'vpx_ports')
| -rw-r--r-- | vpx_ports/x86.h | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/vpx_ports/x86.h b/vpx_ports/x86.h index 970ac2518..ed26b1671 100644 --- a/vpx_ports/x86.h +++ b/vpx_ports/x86.h @@ -202,6 +202,7 @@ static INLINE int x86_simd_caps(void) { // bits 27 (OSXSAVE) & 28 (256-bit AVX) if ((reg_ecx & (BIT(27) | BIT(28))) == (BIT(27) | BIT(28))) { + // Check for OS-support of YMM state. Necessary for AVX and AVX2. if ((xgetbv() & 0x6) == 0x6) { flags |= HAS_AVX; @@ -214,8 +215,10 @@ static INLINE int x86_simd_caps(void) { // bits 16 (AVX-512F) & 17 (AVX-512DQ) & 28 (AVX-512CD) & // 30 (AVX-512BW) & 32 (AVX-512VL) if ((reg_ebx & (BIT(16) | BIT(17) | BIT(28) | BIT(30) | BIT(31))) == - (BIT(16) | BIT(17) | BIT(28) | BIT(30) | BIT(31))) - flags |= HAS_AVX512; + (BIT(16) | BIT(17) | BIT(28) | BIT(30) | BIT(31))) { + // Check for OS-support of ZMM and YMM state. Necessary for AVX-512. + if ((xgetbv() & 0xe6) == 0xe6) flags |= HAS_AVX512; + } } } } |