[Bug middle-end/103439] genemit emits dead code

[rguenther at suse dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103439

--- Comment #2 from rguenther at suse dot de <rguenther at suse dot de> ---
On Fri, 26 Nov 2021, ubizjak at gmail dot com wrote:

> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103439
> 
> --- Comment #1 from Uroš Bizjak <ubizjak at gmail dot com> ---
> (In reply to Richard Biener from comment #0)
> > I'm not sure if there are valid cases where we have a mix of a direct
> > RTL pattern and manual expansion, so where the { } part falls thru.
> 
> Yes, we have quite some of them in e.g. i386.md, movstrict<mode>, extv<mode>,
> extzv<mode>, insv<mode> and zero_extend expanders are some of them.

OK, so that's conditional FAILs.  I've not yet found a conditional
DONE that eventually falls through to a "DONE via the pattern".