Allow null-valued function operands in getCalledFunction()
Summary:
Change the dynamic cast in CallBase::getCalledFunction() to allow
null-valued function operands.
This patch fixes a crash that occurred when a funtion operand of a
call instruction was dropped, and later on a metadata-carrying
instruction was printed out. When allocating the metadata slot numbers,
getCalledFunction() would be invoked on the call with the dropped
operand, resulting in a failed non-null assertion in isa<>.
This fixes PR38924, in which a printout in DBCE crashed due to this.
This aligns getCalledFunction() with getCalledValue(), as the latter
allows the operand to be null.
Reviewers: vsk, dexonsmith, hfinkel
Reviewed By: dexonsmith
Subscribers: hfinkel, llvm-commits
Differential Revision: https://reviews.llvm.org/D52537
llvm-svn: 345966