[Bug rtl-optimization/91154] [10 Regression] 456.hmmer regression on Haswell caused by r272922

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91154

--- Comment #30 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to Richard Biener from comment #29)
> (In reply to Uroš Bizjak from comment #27)
> > (In reply to rguenther@suse.de from comment #25)
> > > and STV converting single-instruction 'chains':
> > > 
> > > Collected chain #40... 
> > >   insns: 381
> > >   defs to convert: r463, r465
> > > Computing gain for chain #40...
> > >   Instruction gain 8 for   381: {r465:SI=smin(r463:SI,[`numBins']);clobber 
> > > flags:CC;}
> > >       REG_DEAD r463:SI
> > >       REG_UNUSED flags:CC
> > >   Instruction conversion gain: 8 
> > >   Registers conversion cost: 4
> > >   Total gain: 4
> > > Converting chain #40...
> > 
> > Is this in STV1 pass? This (pre-combine) pass should be enabled only for
> > TImode conversion, a semi-hack where 64bit targets convert memory access to
> > TImode. General STV should not be ran before combine.
> 
> Yes, this is STV1.  My patch to enable SImode and DImode chains didn't change
> where the pass runs or enable the 2nd run out of compile-time concerns.
> 
> Indeed changing this fixes the issue.  I'm going to benchmark it on
> 300.twolf.

Hmm, it regresses the gcc.target/i386/minmax-6.c though and thus cactusADM
(IIRC).