On Thu, 19 May 2022, Jakub Jelinek wrote:
> On Fri, May 13, 2022 at 12:23:01PM +0200, Richard Biener wrote:
> > 2022-05-13 Richard Biener <rguent...@suse.de>
> >
> > * omp-expand.cc (expand_omp_atomic_cas): Do not short-cut
> > computation of the new value.
>
> Ok, thanks.
>
> Though, depending on what exactly you allow or disallow, maybe even
> the im != 0 might not be acceptable.
> Oh, and if COND_EXPRs can only use some limited set of comparisons, we might
> need to adjust e.g. arith_overflow_check_p and various other spots in
> tree-ssa-math-opts.cc and other passes.
With the changes I have in the queue the !cond_stmt path should be
effectively dead code (though I don't remove such immediately).
Not sure what you think the issue with arith_overflow_check_p would be?
Note this is only about COND_EXPRs in gimple assignments.
I'm going to push this OMP patch later but will delay pushing the
COND_EXPR patches until next week so I'm around more reliably to
deal with fallout.
Richard.
> > diff --git a/gcc/omp-expand.cc b/gcc/omp-expand.cc
> > index ee708314793..9fcc67a3448 100644
> > --- a/gcc/omp-expand.cc
> > +++ b/gcc/omp-expand.cc
> > @@ -9092,16 +9092,17 @@ expand_omp_atomic_cas (basic_block load_bb, tree
> > addr,
> >
> > if (cond_stmt)
> > {
> > - g = gimple_build_assign (gimple_assign_lhs (cond_stmt),
> > - NOP_EXPR, im);
> > + g = gimple_build_assign (cond, NOP_EXPR, im);
> > gimple_set_location (g, loc);
> > gsi_insert_before (&gsi, g, GSI_SAME_STMT);
> > }
> > - else if (need_new)
> > +
> > + if (need_new)
> > {
> > g = gimple_build_assign (create_tmp_reg (itype), COND_EXPR,
> > - build2 (NE_EXPR, boolean_type_node,
> > - im, build_zero_cst (itype)),
> > + cond_stmt
> > + ? cond : build2 (NE_EXPR, boolean_type_node,
> > + im, build_zero_cst (itype)),
> > d, re);
> > gimple_set_location (g, loc);
> > gsi_insert_before (&gsi, g, GSI_SAME_STMT);
> > --
> > 2.35.3
>
> Jakub
>
>
--
Richard Biener <rguent...@suse.de>
SUSE Software Solutions Germany GmbH, Maxfeldstrasse 5, 90409 Nuernberg,
Germany; GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman;
HRB 36809 (AG Nuernberg)
