optimize composite OP silu_double_grad

PaddlePaddle · Feb 27, 2024 · 3df912d · 3df912d
1 parent 7a97c10
commit 3df912d
Showing 1 changed file with 4 additions and 6 deletions.
diff --git a/paddle/fluid/prim/api/composite_backward/composite_double_backward_api.h b/paddle/fluid/prim/api/composite_backward/composite_double_backward_api.h
@@ -441,15 +441,13 @@ void silu_double_grad(const Tensor& x,
                       Tensor* grad_x,
                       Tensor* grad_out_grad) {
   auto sigmoid = 1 / (1 + exp<T>(-x));
-  auto tmp1 = 1 - sigmoid;
-  auto tmp2 = 1 + tmp1 * x;
+  auto ddx_mul_tt = grad_x_grad * (x - out + 1);
   if (grad_out_grad) {
-    auto ddout = grad_x_grad * sigmoid * tmp2;
-    set_output<T>(ddout, grad_out_grad);
+    set_output<T>(ddx_mul_tt * sigmoid, grad_out_grad);
   }
   if (grad_x) {
-    auto dx = sigmoid * grad_x_grad * out_grad * (1 + (tmp2 - out)) * tmp1;
-    set_output<T>(dx, grad_x);
+    auto sigmoid_g = sigmoid * (1 - sigmoid);
+    set_output<T>(ddx_mul_tt * sigmoid_g, grad_x);
   }
 }