AMDGPU: Treat more custom operations as canonicalizing

Everything should quiet, and I think everything should
flush.

I assume the min3/med3/max3 follow the same rules
as regular min/max for flushing, which should at
least be conservatively correct.

There are still more operations that need to
be handled.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@339065 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed