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[x86] Embed brand_string and mark FillX86BrandString as deprecated (#214)

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This commit is contained in:
Guillaume Chatelet
2022-01-14 17:20:31 +01:00
committed by GitHub
parent aa642e573e
commit 149916384b
4 changed files with 67 additions and 15 deletions
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45
src/impl_x86__base_implementation.inl
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@ -184,6 +184,7 @@ static int IsVendorByX86Info(const X86Info* info, const char* const name) {
return equals(info->vendor, name, sizeof(info->vendor));
}
// TODO: Remove when deprecation period is over,
void FillX86BrandString(char brand_string[49]) {
const Leaves leaves = ReadLeaves();
const Leaf packed[3] = {
@ -202,31 +203,33 @@ void FillX86BrandString(char brand_string[49]) {
// CpuId
////////////////////////////////////////////////////////////////////////////////
static bool HasSecondFMA(uint32_t model) {
static bool HasSecondFMA(const X86Info* info) {
// Skylake server
if (model == 0x55) {
char proc_name[49] = {0};
FillX86BrandString(proc_name);
if (info->model == 0x55) {
// detect Xeon
if (proc_name[9] == 'X') {
if (info->brand_string[9] == 'X') {
// detect Silver or Bronze
if (proc_name[17] == 'S' || proc_name[17] == 'B') return false;
if (info->brand_string[17] == 'S' || info->brand_string[17] == 'B')
return false;
// detect Gold 5_20 and below, except for Gold 53__
if (proc_name[17] == 'G' && proc_name[22] == '5')
return ((proc_name[23] == '3') ||
(proc_name[24] == '2' && proc_name[25] == '2'));
if (info->brand_string[17] == 'G' && info->brand_string[22] == '5')
return (
(info->brand_string[23] == '3') ||
(info->brand_string[24] == '2' && info->brand_string[25] == '2'));
// detect Xeon W 210x
if (proc_name[17] == 'W' && proc_name[21] == '0') return false;
if (info->brand_string[17] == 'W' && info->brand_string[21] == '0')
return false;
// detect Xeon D 2xxx
if (proc_name[17] == 'D' && proc_name[19] == '2' && proc_name[20] == '1')
if (info->brand_string[17] == 'D' && info->brand_string[19] == '2' &&
info->brand_string[20] == '1')
return false;
}
return true;
}
// Cannon Lake client
if (model == 0x66) return false;
if (info->model == 0x66) return false;
// Ice Lake client
if (model == 0x7d || model == 0x7e) return false;
if (info->model == 0x7d || info->model == 0x7e) return false;
// This is the right default...
return true;
}
@ -263,10 +266,24 @@ static void ParseCpuId(const Leaves* leaves, X86Info* info,
X86Features* const features = &info->features;
// Fill Family, Model and Stepping.
info->family = extended_family + family;
info->model = (extended_model << 4) + model;
info->stepping = ExtractBitRange(leaf_1.eax, 3, 0);
// Fill Brand String.
const Leaf packed[3] = {
leaves->leaf_80000002,
leaves->leaf_80000003,
leaves->leaf_80000004,
};
#if __STDC_VERSION__ >= 201112L
_Static_assert(sizeof(packed) == 48, "Leaves must be packed");
#endif
copy(info->brand_string, (const char*)(packed), 48);
info->brand_string[48] = '\0';
// Fill cpu features.
features->fpu = IsBitSet(leaf_1.edx, 0);
features->tsc = IsBitSet(leaf_1.edx, 4);
features->cx8 = IsBitSet(leaf_1.edx, 8);
@ -341,7 +358,7 @@ static void ParseCpuId(const Leaves* leaves, X86Info* info,
features->avx512vpopcntdq = IsBitSet(leaf_7.ecx, 14);
features->avx512_4vnniw = IsBitSet(leaf_7.edx, 2);
features->avx512_4vbmi2 = IsBitSet(leaf_7.edx, 3);
features->avx512_second_fma = HasSecondFMA(info->model);
features->avx512_second_fma = HasSecondFMA(info);
features->avx512_4fmaps = IsBitSet(leaf_7.edx, 3);
features->avx512_bf16 = IsBitSet(leaf_7_1.eax, 5);
features->avx512_vp2intersect = IsBitSet(leaf_7.edx, 8);