port of cpu_features

cpu_features.c

#include "cpu_features.h"

#if defined(__x86_64__) || defined(_WIN64)
#ifndef _WIN64
#include <cpuid.h>

unsigned int get_cpuid_max (unsigned int ext, unsigned int *sig) {
    return __get_cpuid_max(ext, sig);
}

int get_cpuid_count (unsigned int leaf, unsigned int subleaf, unsigned int *eax, unsigned int *ebx, unsigned int *ecx, unsigned int *edx) {
    int cpuInfo[4];

    __cpuid_count (leaf, subleaf, *eax, *ebx, *ecx, *edx);
    return 1;
}

int get_cpuid (unsigned int leaf, unsigned int *eax, unsigned int *ebx, unsigned int *ecx, unsigned int *edx) {
    return (get_cpuid_count(leaf, 0, eax, ebx, ecx, edx));
}

#else
#include <intrin.h>

unsigned int get_cpuid_max (unsigned int ext, unsigned int *sig) {
    int cpuInfo[4];

    cpuInfo[0] = 0;
    __cpuidex(cpuInfo, ext, 0);
    *sig = cpuInfo[1];
    return cpuInfo[0];
}

int get_cpuid_count (unsigned int leaf, unsigned int subleaf, unsigned int *eax, unsigned int *ebx, unsigned int *ecx, unsigned int *edx) {
    int cpuInfo[4];

    __cpuidex(cpuInfo, leaf, subleaf);
    *eax = cpuInfo[0];
    *ebx = cpuInfo[1];
    *ecx = cpuInfo[2];
    *edx = cpuInfo[3];
    return 1;
}

int get_cpuid (unsigned int leaf, unsigned int *eax, unsigned int *ebx, unsigned int *ecx, unsigned int *edx) {
    return (get_cpuid_count(leaf, 0, eax, ebx, ecx, edx));
}

#endif



#define bit_CX8_compat           0x00000100
#define bit_SSE41_compat         0x00080000
#define bit_SSE42_compat         0x00100000
#define bit_AES_compat           0x02000000
#define bit_PCLMUL_compat        0x00000002
#define bit_TSC_compat           0x00000010
#define bit_ERMS_compat          0x00000200
#define bit_AVX2_compat          0x00000020
#define bit_PREFETCHW_compat     0x00000100
#define bit_BMI1_compat          0x00000008
#define bit_BMI2_compat          0x00000100
#define bit_AVX512F_compat       0x00010000
#define bit_AVX512DQ_compat      0x00020000
#define bit_AVX512PF_compat      0x04000000
#define bit_AVX512ER_compat      0x08000000
#define bit_AVX512CD_compat      0x10000000
#define bit_AVX512BW_compat      0x40000000
#define bit_RTM_compat           0x00000800
#define bit_ADX_compat           0x00080000
#define bit_SSE4a_compat         0x00000040
#define bit_LZCNT_compat         0x00000020
#define bit_HTT_compat           0x10000000
#define bit_CMOV_compat          0x00008000
#define bit_FXSAVE_compat        0x01000000
#define bit_MMX_compat           0x00800000
#define bit_SSE_compat           0x02000000
#define bit_SSE2_compat          0x04000000
#define bit_SSE3_compat          0x00000001
#define bit_SSSE3_compat         0x00000200
#define bit_POPCNT_compat        0x00800000
#define bit_AVX_compat           0x10000000

/*
 * Extracts the CPU features by using cpuid.h.
 * Note: This function is implemented in C as cpuid.h
 * uses assembly and pollutes registers; it would be
 * difficult to keep track of this in Java.
 */
void determineCPUFeatures(CPUFeatures* features) {
  unsigned int eax, ebx, ecx, edx;
  unsigned int max_level, ext_level;
  unsigned int vendor;

  max_level = get_cpuid_max (0, &vendor);
  if (max_level < 1) {
    return;
  }

  get_cpuid (1, &eax, &ebx, &ecx, &edx);

  features->fCX8  = !!(edx & bit_CX8_compat);
  features->fCMOV = !!(edx & bit_CMOV_compat);
  features->fFXSR = !!(edx & bit_FXSAVE_compat);
  features->fHT   = !!(edx & bit_HTT_compat);
  features->fMMX  = !!(edx & bit_MMX_compat);
  features->fSSE  = !!(edx & bit_SSE_compat);
  features->fSSE2 = !!(edx & bit_SSE2_compat);
  features->fTSC  = !!(edx & bit_TSC_compat);

  features->fSSE3   = !!(ecx & bit_SSE3_compat);
  features->fSSSE3  = !!(ecx & bit_SSSE3_compat);
  features->fSSE41  = !!(ecx & bit_SSE41_compat);
  features->fSSE42  = !!(ecx & bit_SSE42_compat);
  features->fPOPCNT = !!(ecx & bit_POPCNT_compat);
  features->fAVX    = !!(ecx & bit_AVX_compat);
  features->fAES    = !!(ecx & bit_AES_compat);
  features->fCLMUL  = !!(ecx & bit_PCLMUL_compat);

  if (max_level >= 7) {
    get_cpuid_count (7, 0, &eax, &ebx, &ecx, &edx);

    features->fERMS     = !!(ebx & bit_ERMS_compat);
    features->fAVX2     = !!(ebx & bit_AVX2_compat);
    features->fBMI1     = !!(ebx & bit_BMI1_compat);
    features->fBMI2     = !!(ebx & bit_BMI2_compat);
    features->fRTM      = !!(ebx & bit_RTM_compat);
    features->fADX      = !!(ebx & bit_ADX_compat);
    features->fAVX512F  = !!(ebx & bit_AVX512F_compat);
    features->fAVX512DQ = !!(ebx & bit_AVX512DQ_compat);
    features->fAVX512PF = !!(ebx & bit_AVX512PF_compat);
    features->fAVX512ER = !!(ebx & bit_AVX512ER_compat);
    features->fAVX512CD = !!(ebx & bit_AVX512CD_compat);
    features->fAVX512BW = !!(ebx & bit_AVX512BW_compat);
  }

  // figuring out extended features
  /*get_cpuid (0x80000000, &ext_level, &ebx, &ecx, &edx);

  if (ext_level > 0x80000000) {
    get_cpuid (0x80000001, &eax, &ebx, &ecx, &edx);

    features->fSSE4A = !!(ecx & bit_SSE4a_compat);
    features->fLZCNT = !!(ecx & bit_LZCNT_compat);
    features->fAMD3DNOWPREFETCH = !!(ecx & bit_PREFETCHW_compat);
  }*/
}

#else
/*
 * Dummy for non AMD64
 */
void determineCPUFeatures(CPUFeatures* features) {
}
#endif