diff options
Diffstat (limited to 'get_flags_from_cpuid.c')
-rw-r--r-- | get_flags_from_cpuid.c | 101 |
1 files changed, 101 insertions, 0 deletions
diff --git a/get_flags_from_cpuid.c b/get_flags_from_cpuid.c new file mode 100644 index 0000000..37bd943 --- /dev/null +++ b/get_flags_from_cpuid.c @@ -0,0 +1,101 @@ +#include <stdio.h> +#include <stdint.h> +#include <stdlib.h> +#include <string.h> + +#define EDX_MMX_BIT 23 +#define EDX_SSE_BIT 25 +#define EDX_SSE2_BIT 26 +#define ECX_SSE3_BIT 0 +#define ECX_SSSE3_BIT 9 +#define ECX_SSE41_BIT 19 +#define ECX_SSE42_BIT 20 +#define ECX_AVXOS_BIT 27 +#define ECX_AVX_BIT 28 + + +uint64_t get_supported_flags() +{ + uint64_t supp_comp_flgs = 0; + char *comp_flag = NULL; + char SUPPORTED_COMP_FLAGS[] ="FLAGSFROMAUTOCONF\0"; + + for (comp_flag = strtok(SUPPORTED_COMP_FLAGS, " "); comp_flag != NULL; comp_flag = strtok(NULL, " ")) { + if (strncmp(comp_flag, "-m", 2) != 0) { + fprintf(stderr, "Invalid comp_flag: %s\n", comp_flag); + exit(2); + } + if (strcmp(comp_flag, "-mmmx\0") == 0) { + supp_comp_flgs |= (1 << EDX_MMX_BIT); + } + if (strcmp(comp_flag, "-msse\0") == 0) { + supp_comp_flgs |= (1 << EDX_SSE_BIT); + } + if (strcmp(comp_flag, "-msse2\0") == 0) { + supp_comp_flgs |= (1 << EDX_SSE2_BIT); + } + if (strcmp(comp_flag, "-msse3\0") == 0) { + supp_comp_flgs |= (1 << ECX_SSE3_BIT); + } + if (strcmp(comp_flag, "-mssse3\0") == 0) { + supp_comp_flgs |= (1 << ECX_SSSE3_BIT); + } + if (strcmp(comp_flag, "-msse4.1\0") == 0) { + supp_comp_flgs |= (1 << ECX_SSE41_BIT); + } + if (strcmp(comp_flag, "-msse4.2\0") == 0) { + supp_comp_flgs |= (1 << ECX_SSE42_BIT); + } + if (strcmp(comp_flag, "-mavx\0") == 0) { + supp_comp_flgs |= (1 << ECX_AVX_BIT); + } + } + + return supp_comp_flgs; +} + +int is_supported(int cpuid_reg, uint64_t comp_flags, int feature_bit) +{ + return ((cpuid_reg >> feature_bit) & 0x1) && ((comp_flags >> feature_bit) & 0x1); +} + +int main(int argc, char** argv) +{ + int feature_eax, feature_ebx, feature_ecx, feature_edx; + uint64_t supp_comp_flgs = get_supported_flags(argc, argv); + FILE *f = fopen("compiler_flags", "w"); + + __asm__("cpuid" + : "=a" (feature_eax), "=b" (feature_ebx), "=c" (feature_ecx), "=d" (feature_edx) + : "a" (0x00000001)); + + if (is_supported(feature_edx, supp_comp_flgs, EDX_MMX_BIT)) { + fprintf(f, "-mmmx -DINTEL_MMX "); + } + if (is_supported(feature_edx, supp_comp_flgs, EDX_SSE_BIT)) { + fprintf(f, "-msse -DINTEL_SSE "); + } + if (is_supported(feature_edx, supp_comp_flgs, EDX_SSE2_BIT)) { + fprintf(f, "-msse2 -DINTEL_SSE2 "); + } + if (is_supported(feature_ecx, supp_comp_flgs, ECX_SSE3_BIT)) { + fprintf(f, "-msse3 -DINTEL_SSE3 "); + } + if (is_supported(feature_ecx, supp_comp_flgs, ECX_SSSE3_BIT)) { + fprintf(f, "-mssse3 -DINTEL_SSSE3 "); + } + if (is_supported(feature_ecx, supp_comp_flgs, ECX_SSE41_BIT)) { + fprintf(f, "-msse4.1 -DINTEL_SSE41 "); + } + if (is_supported(feature_ecx, supp_comp_flgs, ECX_SSE42_BIT)) { + fprintf(f, "-msse4.2 -DINTEL_SSE42 "); + } + if (is_supported(feature_ecx, supp_comp_flgs, ECX_AVX_BIT)) { + if ((feature_ecx >> ECX_AVXOS_BIT) & 0x1) { + fprintf(f, "-mavx -DINTEL_AVX "); + } + } + fclose(f); + return 0; +} + |