OpenBLAS/kernel/arm64/sgemv_n_neon.c

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

int CNAME(BLASLONG m, BLASLONG n, BLASLONG dummy1, FLOAT alpha, FLOAT *a, BLASLONG lda, FLOAT *x, BLASLONG inc_x, FLOAT *y, BLASLONG inc_y, FLOAT *buffer)
{
  BLASLONG i;
  BLASLONG ix,iy;
  BLASLONG j;
  FLOAT *a_ptr;
  FLOAT temp;

  ix = 0;
  a_ptr = a;

  if (inc_x == 1 && inc_y == 1) {
    FLOAT *a0_ptr = a + lda * 0;
    FLOAT *a1_ptr = a + lda * 1;
    FLOAT *a2_ptr = a + lda * 2;
    FLOAT *a3_ptr = a + lda * 3;
    FLOAT *a4_ptr = a + lda * 4;
    FLOAT *a5_ptr = a + lda * 5;
    FLOAT *a6_ptr = a + lda * 6;
    FLOAT *a7_ptr = a + lda * 7;

    j = 0;
    while (j + 3 < n) {
      float32x4_t x0_vec = vld1q_f32(x + j);
      x0_vec = vmulq_n_f32(x0_vec, alpha);
      i = 0;
      while (i + 7 < m) {
        float32x4_t a00_vec = vld1q_f32(a0_ptr + i);
        float32x4_t a01_vec = vld1q_f32(a0_ptr + i + 4);
        float32x4_t a10_vec = vld1q_f32(a1_ptr + i);
        float32x4_t a11_vec = vld1q_f32(a1_ptr + i + 4);
        float32x4_t a20_vec = vld1q_f32(a2_ptr + i);
        float32x4_t a21_vec = vld1q_f32(a2_ptr + i + 4);
        float32x4_t a30_vec = vld1q_f32(a3_ptr + i);
        float32x4_t a31_vec = vld1q_f32(a3_ptr + i + 4);

        float32x4_t y0_vec = vld1q_f32(y + i);
        float32x4_t y1_vec = vld1q_f32(y + i + 4);
        y0_vec = vmlaq_laneq_f32(y0_vec, a00_vec, x0_vec, 0);
        y0_vec = vmlaq_laneq_f32(y0_vec, a10_vec, x0_vec, 1);
        y0_vec = vmlaq_laneq_f32(y0_vec, a20_vec, x0_vec, 2);
        y0_vec = vmlaq_laneq_f32(y0_vec, a30_vec, x0_vec, 3);
        y1_vec = vmlaq_laneq_f32(y1_vec, a01_vec, x0_vec, 0);
        y1_vec = vmlaq_laneq_f32(y1_vec, a11_vec, x0_vec, 1);
        y1_vec = vmlaq_laneq_f32(y1_vec, a21_vec, x0_vec, 2);
        y1_vec = vmlaq_laneq_f32(y1_vec, a31_vec, x0_vec, 3);

        vst1q_f32(y + i, y0_vec);
        vst1q_f32(y + i + 4, y1_vec);

        i += 8;
      }
      while (i + 3 < m) {
        float32x4_t a0_vec = vld1q_f32(a0_ptr + i);
        float32x4_t a1_vec = vld1q_f32(a1_ptr + i);
        float32x4_t a2_vec = vld1q_f32(a2_ptr + i);
        float32x4_t a3_vec = vld1q_f32(a3_ptr + i);

        float32x4_t y_vec = vld1q_f32(y + i);
        y_vec = vmlaq_laneq_f32(y_vec, a0_vec, x0_vec, 0);
        y_vec = vmlaq_laneq_f32(y_vec, a1_vec, x0_vec, 1);
        y_vec = vmlaq_laneq_f32(y_vec, a2_vec, x0_vec, 2);
        y_vec = vmlaq_laneq_f32(y_vec, a3_vec, x0_vec, 3);

        vst1q_f32(y + i, y_vec);

        i += 4;
      }
      while (i + 1 < m) {
        float32x2_t a0_vec = vld1_f32(a0_ptr + i);
        float32x2_t a1_vec = vld1_f32(a1_ptr + i);
        float32x2_t a2_vec = vld1_f32(a2_ptr + i);
        float32x2_t a3_vec = vld1_f32(a3_ptr + i);

        float32x2_t y_vec = vld1_f32(y + i);
        y_vec = vmla_laneq_f32(y_vec, a0_vec, x0_vec, 0);
        y_vec = vmla_laneq_f32(y_vec, a1_vec, x0_vec, 1);
        y_vec = vmla_laneq_f32(y_vec, a2_vec, x0_vec, 2);
        y_vec = vmla_laneq_f32(y_vec, a3_vec, x0_vec, 3);

        vst1_f32(y + i, y_vec);

        i += 2;
      }
      while (i < m) {
        y[i] += a0_ptr[i] * x0_vec[0];
        y[i] += a1_ptr[i] * x0_vec[1];
        y[i] += a2_ptr[i] * x0_vec[2];
        y[i] += a3_ptr[i] * x0_vec[3];

        i++;
      }

      a0_ptr += lda * 4;
      a1_ptr += lda * 4;
      a2_ptr += lda * 4;
      a3_ptr += lda * 4;

      j += 4;
    }
    while (j + 1 < n) {
      float32x2_t x0_vec = vld1_f32(x + j);
      x0_vec = vmul_n_f32(x0_vec, alpha);
      i = 0;
      while (i + 7 < m) {
        float32x4_t a00_vec = vld1q_f32(a0_ptr + i);
        float32x4_t a01_vec = vld1q_f32(a0_ptr + i + 4);
        float32x4_t a10_vec = vld1q_f32(a1_ptr + i);
        float32x4_t a11_vec = vld1q_f32(a1_ptr + i + 4);

        float32x4_t y0_vec = vld1q_f32(y + i);
        float32x4_t y1_vec = vld1q_f32(y + i + 4);
        y0_vec = vmlaq_lane_f32(y0_vec, a00_vec, x0_vec, 0);
        y0_vec = vmlaq_lane_f32(y0_vec, a10_vec, x0_vec, 1);
        y1_vec = vmlaq_lane_f32(y1_vec, a01_vec, x0_vec, 0);
        y1_vec = vmlaq_lane_f32(y1_vec, a11_vec, x0_vec, 1);

        vst1q_f32(y + i, y0_vec);
        vst1q_f32(y + i + 4, y1_vec);

        i += 8;
      }
      while (i + 3 < m) {
        float32x4_t a0_vec = vld1q_f32(a0_ptr + i);
        float32x4_t a1_vec = vld1q_f32(a1_ptr + i);

        float32x4_t y_vec = vld1q_f32(y + i);
        y_vec = vmlaq_lane_f32(y_vec, a0_vec, x0_vec, 0);
        y_vec = vmlaq_lane_f32(y_vec, a1_vec, x0_vec, 1);

        vst1q_f32(y + i, y_vec);

        i += 4;
      }
      while (i + 1 < m) {
        float32x2_t a0_vec = vld1_f32(a0_ptr + i);
        float32x2_t a1_vec = vld1_f32(a1_ptr + i);

        float32x2_t y_vec = vld1_f32(y + i);
        y_vec = vmla_lane_f32(y_vec, a0_vec, x0_vec, 0);
        y_vec = vmla_lane_f32(y_vec, a1_vec, x0_vec, 1);

        vst1_f32(y + i, y_vec);

        i += 2;
      }
      while (i < m) {
        y[i] += a0_ptr[i] * x0_vec[0];
        y[i] += a1_ptr[i] * x0_vec[1];

        i++;
      }

      a0_ptr += lda * 2;
      a1_ptr += lda * 2;

      j += 2;
    }
    while (j < n) {
      i = 0;
      temp = alpha * x[j];
      while (i < m) {
        y[i] += a0_ptr[i] * temp;
        i++;
      }

      a0_ptr += lda;
      j++;
    }
    return (0);
  }

  for (j = 0; j < n; j++) {
    temp = alpha * x[ix];
    iy = 0;
    for (i = 0; i < m; i++) {
      y[iy] += temp * a_ptr[i];
      iy += inc_y;
    }
    a_ptr += lda;
    ix += inc_x;
  }
  return (0);
}