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Add OsSupport structure

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This commit is contained in:
Corentin Le Molgat 2020-03-12 10:56:06 +01:00 committed by Mizux
parent bee48b4a19
commit 339bfd32be
1 changed files with 22 additions and 19 deletions
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41
src/cpuinfo_x86.c
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@ -1039,17 +1039,25 @@ static void ParseLeaf4(const int max_cpuid_leaf, CacheInfo* info) {
}
}
// Internal structure to hold the OS support for vector operations.
// Avoid to recompute them since each call to cpuid is ~100 cycles.
typedef struct {
bool have_sse;
bool have_avx;
bool have_avx512;
} OsSupport;
// Reference https://en.wikipedia.org/wiki/CPUID.
static void ParseCpuId(const uint32_t max_cpuid_leaf, X86Info* info) {
static void ParseCpuId(const uint32_t max_cpuid_leaf, X86Info* info, OsSupport* os_support) {
const Leaf leaf_1 = SafeCpuId(max_cpuid_leaf, 1);
const Leaf leaf_7 = SafeCpuId(max_cpuid_leaf, 7);
const bool have_xsave = IsBitSet(leaf_1.ecx, 26);
const bool have_osxsave = IsBitSet(leaf_1.ecx, 27);
const uint32_t xcr0_eax = (have_xsave && have_osxsave) ? GetXCR0Eax() : 0;
const bool have_sse_os_support = HasXmmOsXSave(xcr0_eax);
const bool have_avx_os_support = HasYmmOsXSave(xcr0_eax);
const bool have_avx512_os_support = HasZmmOsXSave(xcr0_eax);
os_support->have_sse = HasXmmOsXSave(xcr0_eax);
os_support->have_avx = HasYmmOsXSave(xcr0_eax);
os_support->have_avx512 = HasZmmOsXSave(xcr0_eax);
const uint32_t family = ExtractBitRange(leaf_1.eax, 11, 8);
const uint32_t extended_family = ExtractBitRange(leaf_1.eax, 27, 20);
@ -1090,7 +1098,7 @@ static void ParseCpuId(const uint32_t max_cpuid_leaf, X86Info* info) {
features->vaes = IsBitSet(leaf_7.ecx, 9);
features->vpclmulqdq = IsBitSet(leaf_7.ecx, 10);
if (have_sse_os_support) {
if (os_support->have_sse) {
features->sse = IsBitSet(leaf_1.edx, 25);
features->sse2 = IsBitSet(leaf_1.edx, 26);
features->sse3 = IsBitSet(leaf_1.ecx, 0);
@ -1099,13 +1107,13 @@ static void ParseCpuId(const uint32_t max_cpuid_leaf, X86Info* info) {
features->sse4_2 = IsBitSet(leaf_1.ecx, 20);
}
if (have_avx_os_support) {
if (os_support->have_avx) {
features->fma3 = IsBitSet(leaf_1.ecx, 12);
features->avx = IsBitSet(leaf_1.ecx, 28);
features->avx2 = IsBitSet(leaf_7.ebx, 5);
}
if (have_avx512_os_support) {
if (os_support->have_avx512) {
features->avx512f = IsBitSet(leaf_7.ebx, 16);
features->avx512cd = IsBitSet(leaf_7.ebx, 28);
features->avx512er = IsBitSet(leaf_7.ebx, 27);
@ -1125,41 +1133,36 @@ static void ParseCpuId(const uint32_t max_cpuid_leaf, X86Info* info) {
}
// Reference https://en.wikipedia.org/wiki/CPUID#EAX=80000000h:_Get_Highest_Extended_Function_Implemented.
static void ParseExtraAMDCpuId(const uint32_t max_cpuid_leaf, X86Info* info) {
const Leaf leaf_1 = SafeCpuId(max_cpuid_leaf, 1);
static void ParseExtraAMDCpuId(const uint32_t max_cpuid_leaf, X86Info* info, OsSupport os_support) {
const Leaf leaf_80000000 = CpuId(0x80000000);
const Leaf leaf_80000001 = SafeCpuId(leaf_80000000.eax, 0x80000001);
const bool have_xsave = IsBitSet(leaf_1.ecx, 26);
const bool have_osxsave = IsBitSet(leaf_1.ecx, 27);
const uint32_t xcr0_eax = (have_xsave && have_osxsave) ? GetXCR0Eax() : 0;
const bool have_sse_os_support = HasXmmOsXSave(xcr0_eax);
const bool have_avx_os_support = HasYmmOsXSave(xcr0_eax);
X86Features* const features = &info->features;
if (have_sse_os_support) {
if (os_support.have_sse) {
features->sse4a = IsBitSet(leaf_80000001.ecx, 6);
}
if (have_avx_os_support) {
if (os_support.have_avx) {
features->fma4 = IsBitSet(leaf_80000001.ecx, 16);
}
}
static const X86Info kEmptyX86Info;
static const OsSupport kEmptyOsSupport;
static const CacheInfo kEmptyCacheInfo;
X86Info GetX86Info(void) {
X86Info info = kEmptyX86Info;
OsSupport os_support = kEmptyOsSupport;
const Leaf leaf_0 = CpuId(0);
const uint32_t max_cpuid_leaf = leaf_0.eax;
SetVendor(leaf_0, info.vendor);
if (IsVendor(leaf_0, "GenuineIntel") || IsVendor(leaf_0, "AuthenticAMD")) {
ParseCpuId(max_cpuid_leaf, &info);
ParseCpuId(max_cpuid_leaf, &info, &os_support);
}
if (IsVendor(leaf_0, "AuthenticAMD")) {
ParseExtraAMDCpuId(max_cpuid_leaf, &info);
ParseExtraAMDCpuId(max_cpuid_leaf, &info, os_support);
}
return info;
}