Optimize the following IR:
%1 = tail call noalias i8* @calloc(i64 1, i64 4) %2 = bitcast i8* %1 to i32* ; This store is dead and should be removed store i32 0, i32* %2, align 4
Memory returned by calloc is guaranteed to be zero initialized. If the value being stored is the constant zero (and the store is not otherwise observable across threads), we can delete the store.
Note: I do not have commit rights and will need someone to commit this change after review.