From 2b8aea3adaf3758372c3ec97ee5eda54657df8bb Mon Sep 17 00:00:00 2001
From: Hector Yuen <hyz@fb.com>
Date: Mon, 9 Jul 2018 16:41:45 -0700
Subject: [PATCH] add more logging messages to dimension checks of FCGradient
 (#9203)

Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/9203

Closes https://github.com/pytorch/pytorch/pull/9203

Added extra logging for FCGradient input dimension checks

Reviewed By: yinghai

Differential Revision: D8738549

fbshipit-source-id: d4f26572d86f3d44f40c9dca62d4f241ba15aead
---
 caffe2/operators/fully_connected_op.h | 24 ++++++++++++++++++++++--
 1 file changed, 22 insertions(+), 2 deletions(-)

diff --git a/caffe2/operators/fully_connected_op.h b/caffe2/operators/fully_connected_op.h
index aec48314295..068acfec19c 100644
--- a/caffe2/operators/fully_connected_op.h
+++ b/caffe2/operators/fully_connected_op.h
@@ -184,8 +184,28 @@ class FullyConnectedGradientOp : public Operator<Context> {
     const auto canonical_axis_w = W.canonical_axis_index(axis_w_);
     const int N = TransposeWeight ? W.size_to_dim(canonical_axis_w)
                                   : W.size_from_dim(canonical_axis_w);
-    CAFFE_ENFORCE(M * K == X.size());
-    CAFFE_ENFORCE(K * N == W.size());
+
+    auto dimErrorString = [&]() {
+      return MakeString(
+          "Dimension mismatch: ",
+          "X: ",
+          X.dims(),
+          ", W: ",
+          W.dims(),
+          ", dY: ",
+          dY.dims(),
+          ", axis: ",
+          axis_,
+          ", M: ",
+          M,
+          ", N: ",
+          N,
+          ", K: ",
+          K);
+    };
+
+    CAFFE_ENFORCE(M * K == X.size(), dimErrorString());
+    CAFFE_ENFORCE(K * N == W.size(), dimErrorString());
 
     auto* dW = Output(0);
     auto* db = Output(1);