[BE] Add actual dtype to RuntimeError in ADDMM_META()

Summary: Include actual dtype in RuntimeError

Test Plan: Please see GitHub Actions

Differential Revision: D47506482

fbshipit-source-id: a82c03e2e6d2491d858f49dff20309aac43fc36f

aten/src/ATen/native/LinearAlgebra.cpp

@@ -155,8 +155,8 @@ namespace detail {
 namespace meta {
 
 #define ADDMM_META() \
-  TORCH_CHECK(self.scalar_type() == mat2.scalar_type(), "self and mat2 must have the same dtype"); \
-  TORCH_CHECK(mat1.scalar_type() == mat2.scalar_type(), "mat1 and mat2 must have the same dtype"); \
+  TORCH_CHECK(self.scalar_type() == mat2.scalar_type(), "self and mat2 must have the same dtype, but got ", self.scalar_type(), " and ", mat2.scalar_type()); \
+  TORCH_CHECK(mat1.scalar_type() == mat2.scalar_type(), "mat1 and mat2 must have the same dtype, but got ", mat1.scalar_type(), " and ", mat2.scalar_type()); \
   TORCH_CHECK(mat1.dim() == 2, "mat1 must be a matrix, got ", mat1.dim(), "-D tensor"); \
   TORCH_CHECK(mat2.dim() == 2, "mat2 must be a matrix, got ", mat2.dim(), "-D tensor"); \
   TORCH_CHECK( \