diff options
| author | Frank Barchard <fbarchard@google.com> | 2016-10-18 12:26:02 -0700 |
|---|---|---|
| committer | Frank Barchard <fbarchard@google.com> | 2016-10-18 12:26:02 -0700 |
| commit | e16e3a629f0c1c6ea275fac9798312647056a1ab (patch) | |
| tree | 224dd8050e3b2df2b86764a684b554b0d5478475 /source/cpu_id.cc | |
| parent | 93f47948b13136e449e9feea6c421651aa4f8f5a (diff) | |
| download | libyuv-e16e3a629f0c1c6ea275fac9798312647056a1ab.tar.gz | |
cpu_id cleanup. no functional change.
remove old comment about initialize to zero.
remove ifdef and replace with macro defined to zero.
BUG=None
TEST=try bots
R=kjellander@chromium.org
Review URL: https://codereview.chromium.org/2425623004 .
Diffstat (limited to 'source/cpu_id.cc')
| -rw-r--r-- | source/cpu_id.cc | 11 |
1 files changed, 5 insertions, 6 deletions
diff --git a/source/cpu_id.cc b/source/cpu_id.cc index 4fb168d7..0e541196 100644 --- a/source/cpu_id.cc +++ b/source/cpu_id.cc @@ -68,7 +68,7 @@ void CpuId(uint32 info_eax, uint32 info_ecx, uint32* cpu_info) { if (info_ecx == 0) { __cpuid((int*)(cpu_info), info_eax); } else { - cpu_info[3] = cpu_info[2] = cpu_info[1] = cpu_info[0] = 0; + cpu_info[3] = cpu_info[2] = cpu_info[1] = cpu_info[0] = 0u; } #endif // GCC version uses inline x86 assembly. @@ -114,7 +114,6 @@ void CpuId(uint32 eax, uint32 ecx, uint32* cpu_info) { #if (defined(_M_IX86) || defined(_M_X64) || \ defined(__i386__) || defined(__x86_64__)) && \ !defined(__pnacl__) && !defined(__CLR_VER) && !defined(__native_client__) -#define HAS_XGETBV // X86 CPUs have xgetbv to detect OS saves high parts of ymm registers. int GetXCR0() { uint32 xcr0 = 0u; @@ -125,6 +124,9 @@ int GetXCR0() { #endif // defined(__i386__) || defined(__x86_64__) return xcr0; } +#else +// xgetbv unavailable to query for OSSave support. Return 0. +#define GetXCR0() 0 #endif // defined(_M_IX86) || defined(_M_X64) .. // Return optimization to previous setting. #if defined(_M_IX86) && (_MSC_VER < 1900) @@ -218,7 +220,6 @@ static LIBYUV_BOOL TestEnv(const char*) { LIBYUV_API SAFEBUFFERS int InitCpuFlags(void) { - // TODO(fbarchard): swap kCpuInit logic so 0 means uninitialized. int cpu_info = 0; #if !defined(__pnacl__) && !defined(__CLR_VER) && defined(CPU_X86) uint32 cpu_info0[4] = { 0, 0, 0, 0 }; @@ -236,8 +237,7 @@ int InitCpuFlags(void) { ((cpu_info1[2] & 0x00100000) ? kCpuHasSSE42 : 0) | ((cpu_info7[1] & 0x00000200) ? kCpuHasERMS : 0); -#ifdef HAS_XGETBV - // AVX requires CPU has AVX, XSAVE and OSXSave for xgetbv + // AVX requires OS saves YMM registers. if (((cpu_info1[2] & 0x1c000000) == 0x1c000000) && // AVX and OSXSave ((GetXCR0() & 6) == 6)) { // Test OS saves YMM registers cpu_info |= kCpuHasAVX | @@ -250,7 +250,6 @@ int InitCpuFlags(void) { cpu_info |= (cpu_info7[1] & 0x40000000) ? kCpuHasAVX3 : 0; } } -#endif // Environment variable overrides for testing. if (TestEnv("LIBYUV_DISABLE_X86")) { |