OpenBLAS/kernel/arm64/sbgemv_t_bfdot.c

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#include <arm_neon.h>
#include "common.h"

int CNAME(BLASLONG m, BLASLONG n, float alpha, bfloat16 *a, BLASLONG lda, bfloat16 *x, BLASLONG incx, float beta, float *y, BLASLONG incy)
{
  if (m < 1 || n < 1) return(0);
  BLASLONG i;
  BLASLONG ix,iy;
  BLASLONG j;
  bfloat16_t *a_ptr;
  bfloat16_t *x_ptr;
  float *y_ptr;
  float temp;

  iy = 0;
  a_ptr = (bfloat16_t*)(a);
  x_ptr = (bfloat16_t*)(x);

  if (incx == 1) {
    BLASLONG width = n / 4;

    bfloat16_t *a0_ptr = a_ptr + lda * width * 0;
    bfloat16_t *a1_ptr = a_ptr + lda * width * 1;
    bfloat16_t *a2_ptr = a_ptr + lda * width * 2;
    bfloat16_t *a3_ptr = a_ptr + lda * width * 3;

    float *y0_ptr = y + incy * width * 0;
    float *y1_ptr = y + incy * width * 1;
    float *y2_ptr = y + incy * width * 2;
    float *y3_ptr = y + incy * width * 3;

    for (j = 0; j < width; j++) {
      float32x4_t temp0_vec = vdupq_n_f32(0.0f);
      float32x4_t temp1_vec = vdupq_n_f32(0.0f);
      float32x4_t temp2_vec = vdupq_n_f32(0.0f);
      float32x4_t temp3_vec = vdupq_n_f32(0.0f);

      i = 0;
      while (i + 7 < m) {
        bfloat16x8_t x_vec = vld1q_bf16(x_ptr + i);

        bfloat16x8_t a0_vec = vld1q_bf16(a0_ptr + i);
        bfloat16x8_t a1_vec = vld1q_bf16(a1_ptr + i);
        bfloat16x8_t a2_vec = vld1q_bf16(a2_ptr + i);
        bfloat16x8_t a3_vec = vld1q_bf16(a3_ptr + i);

        temp0_vec = vbfdotq_f32(temp0_vec, a0_vec, x_vec);
        temp1_vec = vbfdotq_f32(temp1_vec, a1_vec, x_vec);
        temp2_vec = vbfdotq_f32(temp2_vec, a2_vec, x_vec);
        temp3_vec = vbfdotq_f32(temp3_vec, a3_vec, x_vec);

        i += 8;
      }
      if (i + 3 < m) {
        float32x2_t t0 = vdup_n_f32(0.0f);
        float32x2_t t1 = vdup_n_f32(0.0f);
        float32x2_t t2 = vdup_n_f32(0.0f);
        float32x2_t t3 = vdup_n_f32(0.0f);

        bfloat16x4_t x_vec = vld1_bf16(x_ptr + i);

        bfloat16x4_t a0_vec = vld1_bf16(a0_ptr + i);
        bfloat16x4_t a1_vec = vld1_bf16(a1_ptr + i);
        bfloat16x4_t a2_vec = vld1_bf16(a2_ptr + i);
        bfloat16x4_t a3_vec = vld1_bf16(a3_ptr + i);

        t0 = vbfdot_f32(t0, a0_vec, x_vec);
        t1 = vbfdot_f32(t1, a1_vec, x_vec);
        t2 = vbfdot_f32(t2, a2_vec, x_vec);
        t3 = vbfdot_f32(t3, a3_vec, x_vec);

        float32x2_t temp0_vec_low = vget_low_f32(temp0_vec);
        float32x2_t temp1_vec_low = vget_low_f32(temp1_vec);
        float32x2_t temp2_vec_low = vget_low_f32(temp2_vec);
        float32x2_t temp3_vec_low = vget_low_f32(temp3_vec);

        temp0_vec = vcombine_f32(vadd_f32(t0, temp0_vec_low), vget_high_f32(temp0_vec));
        temp1_vec = vcombine_f32(vadd_f32(t1, temp1_vec_low), vget_high_f32(temp1_vec));
        temp2_vec = vcombine_f32(vadd_f32(t2, temp2_vec_low), vget_high_f32(temp2_vec));
        temp3_vec = vcombine_f32(vadd_f32(t3, temp3_vec_low), vget_high_f32(temp3_vec));

        i += 4;
      }
      if (beta == 0.0f) {
        y0_ptr[iy] = alpha * vaddvq_f32(temp0_vec);
        y1_ptr[iy] = alpha * vaddvq_f32(temp1_vec);
        y2_ptr[iy] = alpha * vaddvq_f32(temp2_vec);
        y3_ptr[iy] = alpha * vaddvq_f32(temp3_vec);
      }
      else {
        y0_ptr[iy] = alpha * vaddvq_f32(temp0_vec) + beta * y0_ptr[iy];
        y1_ptr[iy] = alpha * vaddvq_f32(temp1_vec) + beta * y1_ptr[iy];
        y2_ptr[iy] = alpha * vaddvq_f32(temp2_vec) + beta * y2_ptr[iy];
        y3_ptr[iy] = alpha * vaddvq_f32(temp3_vec) + beta * y3_ptr[iy];
      }

      for (; i < m; ++i) {
        y0_ptr[iy] += alpha * vcvtah_f32_bf16(a0_ptr[i]) * vcvtah_f32_bf16(x_ptr[i]);
        y1_ptr[iy] += alpha * vcvtah_f32_bf16(a1_ptr[i]) * vcvtah_f32_bf16(x_ptr[i]);
        y2_ptr[iy] += alpha * vcvtah_f32_bf16(a2_ptr[i]) * vcvtah_f32_bf16(x_ptr[i]);
        y3_ptr[iy] += alpha * vcvtah_f32_bf16(a3_ptr[i]) * vcvtah_f32_bf16(x_ptr[i]);
      }

      iy += incy;

      a0_ptr += lda;
      a1_ptr += lda;
      a2_ptr += lda;
      a3_ptr += lda;
    }

    a_ptr = a3_ptr;
    y_ptr = y3_ptr;
    for (j = width * 4; j < n; j++) {
      float32x4_t temp0_vec = vdupq_n_f32(0.0f);
      i = 0;
      while (i + 7 < m) {
        bfloat16x8_t x_vec = vld1q_bf16(x_ptr + i);
        bfloat16x8_t a0_vec = vld1q_bf16(a_ptr + i);
        temp0_vec = vbfdotq_f32(temp0_vec, a0_vec, x_vec);

        i += 8;
      }
      if (i + 3 < m) {
        float32x2_t t0 = vdup_n_f32(0.0f);
        bfloat16x4_t x_vec = vld1_bf16(x_ptr + i);
        bfloat16x4_t a0_vec = vld1_bf16(a_ptr + i);

        t0 = vbfdot_f32(t0, a0_vec, x_vec);
        float32x2_t temp0_vec_low = vget_low_f32(temp0_vec);
        temp0_vec = vcombine_f32(vadd_f32(t0, temp0_vec_low), vget_high_f32(temp0_vec));

        i += 4;
      }
      if (beta == 0.0f) {
        y_ptr[iy] = alpha * vaddvq_f32(temp0_vec);
      }
      else {
        y_ptr[iy] = alpha * vaddvq_f32(temp0_vec) + beta * y_ptr[iy];
      }

      for (; i < m; ++i) {
        y_ptr[iy] += alpha * vcvtah_f32_bf16(a_ptr[i]) * vcvtah_f32_bf16(x_ptr[i]);
      }

      iy += incy;

      a_ptr += lda;
    }
    return(0);
  }

  for (j = 0; j < n; j++) {
    temp = 0.0;
    ix = 0;
    for (i = 0; i < m; i++) {
      temp += vcvtah_f32_bf16(a_ptr[i]) * vcvtah_f32_bf16(x_ptr[ix]);
      ix += incx;
    }
    if (beta == 0.0f) {
      y[iy] = alpha * temp;
    }
    else {
      y[iy] = alpha * temp + beta * y[iy];
    }
    iy += incy;
    a_ptr += lda;
  }
  return (0);
}