482898d9e2
Keeping bitcasts in the common_bitcast() test, otherwise sinking no longer occurs there. GVNSink seems to have a silly cost model where sinking just the stores is considered non-profitable, but sinking the stores and bitcasts (which are free...) is profitable. As this is not a default-enabled pass, and this problem would exist without opaque pointers as well, I'm not trying to do anything about this.