On Wed, 22 Nov 2017, Jakub Jelinek wrote: > On Wed, Nov 22, 2017 at 10:42:13AM +0100, Richard Biener wrote: > > On Wed, 22 Nov 2017, Jakub Jelinek wrote: > > > > > Hi! > > > > > > Seems at least the scheduler treats UNSPEC_VOLATILE and perhaps volatile > > > asm > > > in DEBUG_INSNs as having side-effects and schedules differently depending > > > on > > > that. While we could tweak the scheduler not to do that, these will be > > > actually never useful in DEBUG_INSNs anyway, we don't know what it means > > > so > > > we can't represent it in debug info. > > > > > > So, the following patch just makes sure we don't add them into > > > debug_insns, > > > instead reset those. > > > > > > Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? > > > > Ok. > > > > Do we have some RTL IL verifier where we could verify those don't appear? > > Maybe ICE in dwarf2out.c? > > dwarf2out.c would ICE on UNSPEC_VOLATILE (but not ASM_OPERANDS), no idea why > it didn't make all the way up to there. > In any case, a more useful verifier would be something like we have for > GIMPLE verification, something that walks the whole IL after every pass and > ICEs if something fails verification. We don't have that for RTL and I > think we should, it would e.g. catch the various cases where backends just > use invalid RTL in their patterns on which e.g. simplify-rtx.c could just > ICE if it made it there.
Yes. Too bad we don't have such thing. Richard.
