RFC: peephole vs RTX_FRAME_RELATED_P

[Hans-Peter Nilsson]

On Mon, 19 Dec 2005, Richard Henderson wrote:
> I think that this is all complicated enough that we should
> simply deny peepholing insns with RTX_FRAME_RELATED_P set.

I was just bitten by the same behavior for define_split.
Should the same go for define_splits and maybe also as a guard
test for combine?  Maybe a utility function to use by all insn
transformations?

brgds, H-P