From 7a15a8370c44fceab5d9a33435f0df0bc5b910fe Mon Sep 17 00:00:00 2001
From: xaedes <xaedes@gmail.com>
Date: Sat, 6 May 2023 17:37:51 +0200
Subject: [PATCH] implement backward pass for ggml_sum_rows, necessary for
 cross entropy loss

---
 ggml.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/ggml.c b/ggml.c
index c802be1f2..95c273be3 100644
--- a/ggml.c
+++ b/ggml.c
@@ -13280,7 +13280,15 @@ static void ggml_compute_backward(struct ggml_context * ctx, struct ggml_tensor
             } break;
         case GGML_OP_SUM_ROWS:
             {
-                GGML_ASSERT(false); // TODO: implement
+                if (src0->grad) {
+                    src0->grad =
+                        ggml_add_impl(ctx,
+                                src0->grad,
+                                ggml_repeat(ctx,
+                                    tensor->grad,
+                                    src0->grad),
+                                inplace);
+                }
             } break;
         case GGML_OP_MEAN:
             {