I was worried we might replace a mul with a mul+shift even if there were later
uses. Turns out to be unfounded but I'd just as well add an actual test for it.
llvm-svn: 302051
When we replaced the multiplicand the destination node might already exist.
When that happens the original gets CSEd and deleted. However, it's actually
used as the offset so nonsense is produced.
Should fix PR32726.
llvm-svn: 301983