On Fri, Aug 25, 2023 at 11:11 AM Andrew Pinski <pins...@gmail.com> wrote:
>
> On Thu, Aug 24, 2023 at 11:39 PM Richard Biener via Gcc-patches
> <gcc-patches@gcc.gnu.org> wrote:
> >
> > On Thu, Aug 24, 2023 at 9:16 PM Andrew Pinski via Gcc-patches
> > <gcc-patches@gcc.gnu.org> wrote:
> > >
> > > In PR 106677, I noticed that on the trunk we were producing:
> > > ```
> > > _25 = SR.116_117 == 0;
> > > _27 = (unsigned char) _25;
> > > _32 = _27 | SR.116_117;
> > > ```
> > > From `SR.115_117 != 0 ? SR.115_117 : 1`
> > > Rather than:
> > > ```
> > > _119 = MAX_EXPR <1, SR.115_117>;
> > > ```
> > > Or (rather)
> > > ```
> > > _119 = SR.115_117 | 1;
> > > ```
> > > Due to the order of the patterns.
> >
> > Hmm, that means the former when present in source isn't optimized?
>
> That it is correct; they are not optimized at the gimple level down to
> 1. it is sometimes (but not on all targets) optimized at the RTL level
> though.
I forgot to mention that this is recorded as PR 110637 already.
Thanks,
Andrew
>
> >
> > > OK? Bootstrapped and tested on x86_64-linux-gnu with no
> > > regressions.
> >
> > OK, but please add a comment indicating the ordering requirement.
> >
> > Can you also add a testcase?
>
> Yes and yes. Will send out a new patch in a few minutes with the added
> comment and testcase.
>
> Thanks,
> Andrew
>
> >
> > Richard.
> >
> > > gcc/ChangeLog:
> > >
> > > * match.pd (`a ? one_zero : one_zero`): Move
> > > below detection of minmax.
> > > ---
> > > gcc/match.pd | 38 ++++++++++++++++++++------------------
> > > 1 file changed, 20 insertions(+), 18 deletions(-)
> > >
> > > diff --git a/gcc/match.pd b/gcc/match.pd
> > > index 890f050cbad..c87a0795667 100644
> > > --- a/gcc/match.pd
> > > +++ b/gcc/match.pd
> > > @@ -4950,24 +4950,6 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
> > > )
> > > )
> > >
> > > -(simplify
> > > - (cond @0 zero_one_valued_p@1 zero_one_valued_p@2)
> > > - (switch
> > > - /* bool0 ? bool1 : 0 -> bool0 & bool1 */
> > > - (if (integer_zerop (@2))
> > > - (bit_and (convert @0) @1))
> > > - /* bool0 ? 0 : bool2 -> (bool0^1) & bool2 */
> > > - (if (integer_zerop (@1))
> > > - (bit_and (bit_xor (convert @0) { build_one_cst (type); } ) @2))
> > > - /* bool0 ? 1 : bool2 -> bool0 | bool2 */
> > > - (if (integer_onep (@1))
> > > - (bit_ior (convert @0) @2))
> > > - /* bool0 ? bool1 : 1 -> (bool0^1) | bool1 */
> > > - (if (integer_onep (@2))
> > > - (bit_ior (bit_xor (convert @0) @2) @1))
> > > - )
> > > -)
> > > -
> > > /* Optimize
> > > # x_5 in range [cst1, cst2] where cst2 = cst1 + 1
> > > x_5 ? cstN ? cst4 : cst3
> > > @@ -5298,6 +5280,26 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
> > > && integer_nonzerop (fold_build2 (GE_EXPR, boolean_type_node,
> > > @3, @1)))
> > > (max @2 @4))))))
> > >
> > > +#if GIMPLE
> > > +(simplify
> > > + (cond @0 zero_one_valued_p@1 zero_one_valued_p@2)
> > > + (switch
> > > + /* bool0 ? bool1 : 0 -> bool0 & bool1 */
> > > + (if (integer_zerop (@2))
> > > + (bit_and (convert @0) @1))
> > > + /* bool0 ? 0 : bool2 -> (bool0^1) & bool2 */
> > > + (if (integer_zerop (@1))
> > > + (bit_and (bit_xor (convert @0) { build_one_cst (type); } ) @2))
> > > + /* bool0 ? 1 : bool2 -> bool0 | bool2 */
> > > + (if (integer_onep (@1))
> > > + (bit_ior (convert @0) @2))
> > > + /* bool0 ? bool1 : 1 -> (bool0^1) | bool1 */
> > > + (if (integer_onep (@2))
> > > + (bit_ior (bit_xor (convert @0) @2) @1))
> > > + )
> > > +)
> > > +#endif
> > > +
> > > /* X != C1 ? -X : C2 simplifies to -X when -C1 == C2. */
> > > (simplify
> > > (cond (ne @0 INTEGER_CST@1) (negate@3 @0) INTEGER_CST@2)
> > > --
> > > 2.31.1
> > >
