Use scalar implementation instead of neon implementation to avoid out of range...

Use scalar implementation instead of neon implementation to avoid out of range memory access in the tail conv3x3.

paddle/function/neon/NeonDepthwiseConv.h

@@ -18,7 +18,6 @@ limitations under the License. */
 #include "neon_util.h"
 
 namespace paddle {
-
 namespace neon {
 
 #if defined(__ARM_NEON__) || defined(__ARM_NEON)
@@ -26,17 +25,20 @@ namespace neon {
 template <int filterSize, int stride>
 struct DepthwiseConvKernel {};
 
-inline float32_t conv3x3(float32x4_t r0,
-                         float32x4_t r1,
-                         float32x4_t r2,
+inline float32_t conv3x3(const float* r0,
+                         const float* r1,
+                         const float* r2,
                          float32x4_t k0,
                          float32x4_t k1,
                          float32x4_t k2) {
-  float32x4_t tmp;
-  tmp = vmulq_f32(r0, k0);
-  tmp = vmlaq_f32(tmp, r1, k1);
-  tmp = vmlaq_f32(tmp, r2, k2);
-  return vaddvq_f32(tmp);
+  float32_t tmp[12];
+  vst1q_f32(&(tmp[0]), k0);
+  vst1q_f32(&(tmp[4]), k1);
+  vst1q_f32(&(tmp[8]), k2);
+  float32_t sum0 = r0[0] * tmp[0] + r0[1] * tmp[1] + r0[2] * tmp[2];
+  float32_t sum1 = r1[0] * tmp[4] + r1[1] * tmp[5] + r1[2] * tmp[6];
+  float32_t sum2 = r2[0] * tmp[8] + r2[1] * tmp[9] + r2[2] * tmp[10];
+  return sum0 + sum1 + sum2;
 }
 
 inline float32_t conv4x4(float32x4_t r0,
@@ -136,10 +138,7 @@ struct DepthwiseConvKernel<3, 1> {
         }
 
         for (int r = 0; r < remain; r++) {
-          float32x4_t i0 = vld1q_f32(r0);
-          float32x4_t i1 = vld1q_f32(r1);
-          float32x4_t i2 = vld1q_f32(r2);
-          *outputData = conv3x3(i0, i1, i2, k[0], k[1], k[2]);
+          *outputData = conv3x3(r0, r1, r2, k[0], k[1], k[2]);
           r0++;
           r1++;
           r2++;
@@ -243,10 +242,7 @@ struct DepthwiseConvKernel<3, 2> {
         }
 
         for (int r = 0; r < remain; r++) {
-          float32x4_t i0 = vld1q_f32(r0);
-          float32x4_t i1 = vld1q_f32(r1);
-          float32x4_t i2 = vld1q_f32(r2);
-          *outputData = conv3x3(i0, i1, i2, k[0], k[1], k[2]);
+          *outputData = conv3x3(r0, r1, r2, k[0], k[1], k[2]);
           r0 += 2;
           r1 += 2;
           r2 += 2;