OpenBLAS/test/compare_sgemm_bgemm.c

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#include "../common.h"
#include <stdint.h>
#include <stdio.h>

#include <arm_neon.h>

#define SGEMM BLASFUNC(sgemm)
#define BGEMM BLASFUNC(bgemm)
#define BGEMM_LARGEST 256

typedef union
{
  unsigned short v;
#if defined(_AIX)
  struct __attribute__((packed))
#else
  struct
#endif
  {
#if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
    unsigned short s:1;
    unsigned short e:8;
    unsigned short m:7;
#else
    unsigned short m:7;
    unsigned short e:8;
    unsigned short s:1;
#endif
  } bits;
} bfloat16_bits;

typedef union
{
  float v;
#if defined(_AIX)
  struct __attribute__((packed))
#else
  struct
#endif
  {
#if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
    uint32_t s:1;
    uint32_t e:8;
    uint32_t m:23;
#else
    uint32_t m:23;
    uint32_t e:8;
    uint32_t s:1;
#endif
  } bits;
} float32_bits;

float
float16to32 (bfloat16_bits f16)
{
  float32_bits f32;
  f32.bits.s = f16.bits.s;
  f32.bits.e = f16.bits.e;
  f32.bits.m = (uint32_t) f16.bits.m << 16;
  return f32.v;
}

bfloat16
float32to16 (float32_bits f32)
{
  bfloat16_bits f16;
  f16.bits.s = f32.bits.s;
  f16.bits.e = f32.bits.e;
  f16.bits.m = (f32.bits.m >> 16) & 0x7f;
  return f16.v;
}

static float truncate_float(float value) {
  bfloat16_bits f16 = (bfloat16_bits)float32to16((float32_bits)value);
  return float16to32(f16);
}

void *malloc_safe(size_t size) {
  if (size == 0)
    return malloc(1);
  else
    return malloc(size);
}

int
main (int argc, char *argv[])
{
  blasint m, n, k;
  int i, j, l;
  blasint x, y;
  int ret = 0;
  int loop = BGEMM_LARGEST;
  char transA = 'N', transB = 'N';
  float alpha = 1.0, beta = 0.0;
  bfloat16 alpha_bf16 = float32to16((float32_bits)alpha);
  bfloat16 beta_bf16 = float32to16((float32_bits)beta);

  for (x = 0; x <= loop; x++)
  {
    if ((x > 100) && (x != BGEMM_LARGEST)) continue;
    m = k = n = x;
    float *A = (float *)malloc_safe(m * k * sizeof(FLOAT));
    float *B = (float *)malloc_safe(k * n * sizeof(FLOAT));
    float *C = (float *)malloc_safe(m * n * sizeof(FLOAT));
    bfloat16_bits *AA = (bfloat16_bits *)malloc_safe(m * k * sizeof(bfloat16_bits));
    bfloat16_bits *BB = (bfloat16_bits *)malloc_safe(k * n * sizeof(bfloat16_bits));
    bfloat16_bits *CC = (bfloat16_bits *)malloc_safe(k * n * sizeof(bfloat16_bits));
    FLOAT *DD = (FLOAT *)malloc_safe(m * n * sizeof(FLOAT));
    if ((A == NULL) || (B == NULL) || (C == NULL) || (AA == NULL) || (BB == NULL) ||
        (DD == NULL) || (CC == NULL))
      return 1;
    bfloat16 atmp,btmp;
    blasint one=1;

    for (j = 0; j < m; j++)
    {
      for (i = 0; i < k; i++)
      {
        A[j * k + i] = ((FLOAT) rand () / (FLOAT) RAND_MAX) + 0.5;
        sbstobf16_(&one, &A[j*k+i], &one, &atmp, &one);
        AA[j * k + i].v = atmp;
      }
    }
    for (j = 0; j < n; j++)
    {
      for (i = 0; i < k; i++)
      {
        B[j * k + i] = ((FLOAT) rand () / (FLOAT) RAND_MAX) + 0.5;
        sbstobf16_(&one, &B[j*k+i], &one, &btmp, &one);
        BB[j * k + i].v = btmp;
      }
    }
    for (y = 0; y < 4; y++)
    {
      if ((y == 0) || (y == 2)) {
        transA = 'N';
      } else {
        transA = 'T';
      }
      if ((y == 0) || (y == 1)) {
        transB = 'N';
      } else {
        transB = 'T';
      }

      memset(CC, 0, m * n * sizeof(bfloat16_bits));
      memset(DD, 0, m * n * sizeof(FLOAT));
      memset(C, 0, m * n * sizeof(FLOAT));

      SGEMM (&transA, &transB, &m, &n, &k, &alpha, A,
        &m, B, &k, &beta, C, &m);
      BGEMM (&transA, &transB, &m, &n, &k, &alpha_bf16, (bfloat16*) AA,
        &m, (bfloat16*)BB, &k, &beta_bf16, (bfloat16*)CC, &m);

      for (i = 0; i < n; i++)
        for (j = 0; j < m; j++)
        {
          for (l = 0; l < k; l++)
            if (transA == 'N' && transB == 'N')
            {
              DD[i * m + j] +=
                float16to32 (AA[l * m + j]) * float16to32 (BB[l + k * i]);
            } else if (transA == 'T' && transB == 'N')
            {
              DD[i * m + j] +=
                float16to32 (AA[k * j + l]) * float16to32 (BB[l + k * i]);
            } else if (transA == 'N' && transB == 'T')
            {
              DD[i * m + j] +=
                float16to32 (AA[l * m + j]) * float16to32 (BB[i + l * n]);
            } else if (transA == 'T' && transB == 'T')
            {
              DD[i * m + j] +=
                float16to32 (AA[k * j + l]) * float16to32 (BB[i + l * n]);
            }
          if (fabs(float16to32(CC[i * m + j]) - truncate_float(C[i * m + j])) > 2.0) {
            ret++;
          }
          if (fabs(float16to32(CC[i * m + j]) - truncate_float(DD[i * m + j])) > 1.0) {
            ret++;
          }
            
        }
    }
    free(A);
    free(B);
    free(C);
    free(AA);
    free(BB);
    free(CC);
    free(DD);
  }

  if (ret != 0) {
    fprintf (stderr, "FATAL ERROR BGEMM - Return code: %d\n", ret);
    return ret;
  }
}