replace customize bf16_to_fp32 with arm neon vcvtah_f32_bf16

kernel/arm64/sbgemv_n_neon.c

@@ -33,16 +33,6 @@ THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #include "common.h"
 #include <arm_neon.h>
 
-#if (defined(__GNUC__) && __GNUC__ >= 13)
-#define BF16_TO_FP32(bf16) ((float)(bf16))
-#else
-static inline float bf16_to_fp32(bfloat16_t bf16) {
-   uint32_t fp32 = (uint32_t)(*((u_int16_t*)(&bf16))) << 16;
-   return *((float*)&fp32);
-}
-#define BF16_TO_FP32(bf16) bf16_to_fp32(bf16)
-#endif
-
 static void beta_op(float *x, BLASLONG n, FLOAT beta) {
   if (beta == 0) {
     memset(x, 0, n * sizeof(float));
@@ -268,24 +258,24 @@ int CNAME(BLASLONG m, BLASLONG n, FLOAT alpha, bfloat16 *a, BLASLONG lda,
       }
 
       if (rest_m) {
-        x0 = alpha * BF16_TO_FP32(x_ptr[0]);
-        x1 = alpha * BF16_TO_FP32(x_ptr[1]);
-        x2 = alpha * BF16_TO_FP32(x_ptr[2]);
-        x3 = alpha * BF16_TO_FP32(x_ptr[3]);
-        x4 = alpha * BF16_TO_FP32(x_ptr[4]);
-        x5 = alpha * BF16_TO_FP32(x_ptr[5]);
-        x6 = alpha * BF16_TO_FP32(x_ptr[6]);
-        x7 = alpha * BF16_TO_FP32(x_ptr[7]);
+        x0 = alpha * vcvtah_f32_bf16(x_ptr[0]);
+        x1 = alpha * vcvtah_f32_bf16(x_ptr[1]);
+        x2 = alpha * vcvtah_f32_bf16(x_ptr[2]);
+        x3 = alpha * vcvtah_f32_bf16(x_ptr[3]);
+        x4 = alpha * vcvtah_f32_bf16(x_ptr[4]);
+        x5 = alpha * vcvtah_f32_bf16(x_ptr[5]);
+        x6 = alpha * vcvtah_f32_bf16(x_ptr[6]);
+        x7 = alpha * vcvtah_f32_bf16(x_ptr[7]);
 
         for (BLASLONG j = 0; j < rest_m; j++) {
-          y_ptr[j] += x0 * BF16_TO_FP32(a_ptr0[j]);
-          y_ptr[j] += x1 * BF16_TO_FP32(a_ptr1[j]);
-          y_ptr[j] += x2 * BF16_TO_FP32(a_ptr2[j]);
-          y_ptr[j] += x3 * BF16_TO_FP32(a_ptr3[j]);
-          y_ptr[j] += x4 * BF16_TO_FP32(a_ptr4[j]);
-          y_ptr[j] += x5 * BF16_TO_FP32(a_ptr5[j]);
-          y_ptr[j] += x6 * BF16_TO_FP32(a_ptr6[j]);
-          y_ptr[j] += x7 * BF16_TO_FP32(a_ptr7[j]);
+          y_ptr[j] += x0 * vcvtah_f32_bf16(a_ptr0[j]);
+          y_ptr[j] += x1 * vcvtah_f32_bf16(a_ptr1[j]);
+          y_ptr[j] += x2 * vcvtah_f32_bf16(a_ptr2[j]);
+          y_ptr[j] += x3 * vcvtah_f32_bf16(a_ptr3[j]);
+          y_ptr[j] += x4 * vcvtah_f32_bf16(a_ptr4[j]);
+          y_ptr[j] += x5 * vcvtah_f32_bf16(a_ptr5[j]);
+          y_ptr[j] += x6 * vcvtah_f32_bf16(a_ptr6[j]);
+          y_ptr[j] += x7 * vcvtah_f32_bf16(a_ptr7[j]);
         }
       }
 
@@ -384,16 +374,16 @@ int CNAME(BLASLONG m, BLASLONG n, FLOAT alpha, bfloat16 *a, BLASLONG lda,
       }
 
       if (rest_m) {
-        x0 = alpha * BF16_TO_FP32(x_ptr[0]);
-        x1 = alpha * BF16_TO_FP32(x_ptr[1]);
-        x2 = alpha * BF16_TO_FP32(x_ptr[2]);
-        x3 = alpha * BF16_TO_FP32(x_ptr[3]);
+        x0 = alpha * vcvtah_f32_bf16(x_ptr[0]);
+        x1 = alpha * vcvtah_f32_bf16(x_ptr[1]);
+        x2 = alpha * vcvtah_f32_bf16(x_ptr[2]);
+        x3 = alpha * vcvtah_f32_bf16(x_ptr[3]);
 
         for (BLASLONG j = 0; j < rest_m; j++) {
-          y_ptr[j] += x0 * BF16_TO_FP32(a_ptr0[j]);
-          y_ptr[j] += x1 * BF16_TO_FP32(a_ptr1[j]);
-          y_ptr[j] += x2 * BF16_TO_FP32(a_ptr2[j]);
-          y_ptr[j] += x3 * BF16_TO_FP32(a_ptr3[j]);
+          y_ptr[j] += x0 * vcvtah_f32_bf16(a_ptr0[j]);
+          y_ptr[j] += x1 * vcvtah_f32_bf16(a_ptr1[j]);
+          y_ptr[j] += x2 * vcvtah_f32_bf16(a_ptr2[j]);
+          y_ptr[j] += x3 * vcvtah_f32_bf16(a_ptr3[j]);
         }
       }
 
@@ -480,13 +470,13 @@ int CNAME(BLASLONG m, BLASLONG n, FLOAT alpha, bfloat16 *a, BLASLONG lda,
       }
 
       if (m & 2) {
-        x0 = alpha * (BF16_TO_FP32(x_ptr[0]));
-        x1 = alpha * (BF16_TO_FP32(x_ptr[1]));
+        x0 = alpha * (vcvtah_f32_bf16(x_ptr[0]));
+        x1 = alpha * (vcvtah_f32_bf16(x_ptr[1]));
 
-        y_ptr[0] += x0 * BF16_TO_FP32(a_ptr0[0]);
-        y_ptr[0] += x1 * BF16_TO_FP32(a_ptr1[0]);
-        y_ptr[1] += x0 * BF16_TO_FP32(a_ptr0[1]);
-        y_ptr[1] += x1 * BF16_TO_FP32(a_ptr1[1]);
+        y_ptr[0] += x0 * vcvtah_f32_bf16(a_ptr0[0]);
+        y_ptr[0] += x1 * vcvtah_f32_bf16(a_ptr1[0]);
+        y_ptr[1] += x0 * vcvtah_f32_bf16(a_ptr0[1]);
+        y_ptr[1] += x1 * vcvtah_f32_bf16(a_ptr1[1]);
 
         a_ptr0 += 2;
         a_ptr1 += 2;
@@ -495,23 +485,23 @@ int CNAME(BLASLONG m, BLASLONG n, FLOAT alpha, bfloat16 *a, BLASLONG lda,
       }
 
       if (m & 1) {
-        x0 = alpha * BF16_TO_FP32(x_ptr[0]);
-        x1 = alpha * BF16_TO_FP32(x_ptr[1]);
+        x0 = alpha * vcvtah_f32_bf16(x_ptr[0]);
+        x1 = alpha * vcvtah_f32_bf16(x_ptr[1]);
 
-        y_ptr[0] += x0 * BF16_TO_FP32(a_ptr0[0]);
-        y_ptr[0] += x1 * BF16_TO_FP32(a_ptr1[0]);
+        y_ptr[0] += x0 * vcvtah_f32_bf16(a_ptr0[0]);
+        y_ptr[0] += x1 * vcvtah_f32_bf16(a_ptr1[0]);
       }
 
       x_ptr += 2;
     }
 
     if (n & 1) {
-      x0 = BF16_TO_FP32(x_ptr[0]) * alpha;
+      x0 = vcvtah_f32_bf16(x_ptr[0]) * alpha;
       y_ptr = y;
       a_ptr0 = a_ptr;
 
       for (j = 0; j < m; j++) {
-        y_ptr[j] += x0 * BF16_TO_FP32(a_ptr0[j]);
+        y_ptr[j] += x0 * vcvtah_f32_bf16(a_ptr0[j]);
       }
     }
 
@@ -525,10 +515,10 @@ int CNAME(BLASLONG m, BLASLONG n, FLOAT alpha, bfloat16 *a, BLASLONG lda,
    }
 
   for (j = 0; j < n; j++) {
-    x0 = alpha * BF16_TO_FP32(*x_ptr);
+    x0 = alpha * vcvtah_f32_bf16(*x_ptr);
     iy = 0;
     for (i = 0; i < m; i++) {
-      y[iy] += x0 * BF16_TO_FP32(a_ptr[i]);
+      y[iy] += x0 * vcvtah_f32_bf16(a_ptr[i]);
       iy += incy;
     }