[InlineFunction] Preserve calling convention when forwarding VarArgs.

Reviewers: efriedma, rnk, davide

Reviewed By: rnk, davide

Differential Revision: https://reviews.llvm.org/D41556

llvm-svn: 321943
diff --git a/llvm/lib/Transforms/Utils/InlineFunction.cpp b/llvm/lib/Transforms/Utils/InlineFunction.cpp
index 5574a3d..a96f78e 100644
--- a/llvm/lib/Transforms/Utils/InlineFunction.cpp
+++ b/llvm/lib/Transforms/Utils/InlineFunction.cpp
@@ -1860,6 +1860,7 @@
                                Params, "", CI);
           NewCI->setDebugLoc(CI->getDebugLoc());
           NewCI->setAttributes(Attrs);
+          NewCI->setCallingConv(CI->getCallingConv());
           CI->replaceAllUsesWith(NewCI);
           CI->eraseFromParent();
           CI = NewCI;