Here is the patch that I pushed. Thanks for the feedback.

Thanks
-Sam

On Thu, Jul 28, 2022 at 3:03 AM Richard Biener <richard.guenther@gmail.com>
wrote:

> On Wed, Jul 27, 2022 at 9:57 PM Sam Feifer <sfeifer@redhat.com> wrote:
> >
> >
> >> _Complex int are strange beasts, I'd simply avoid the transform for
> them.
> >>
> >
> > I added to the match.pd rule to not simplify if the operands are
> complex. There is now a test case for complex types to make sure they do
> not simplify. I had to move the "dg-do run" test to g++.dg to accommodate
> the complex type function that is included (even though there isn't a
> runtime test for complex types).
> >
> >> Can you please move the pattern next to the existing div/mod patterns,
> >> like after the related
> >>
> >
> > done :)
> >
> >> /* Simplify (A / B) * B + (A % B) -> A.  */
> >> (for div (trunc_div ceil_div floor_div round_div)
> >>      mod (trunc_mod ceil_mod floor_mod round_mod)
> >>   (simplify
> >>    (plus:c (mult:c (div @0 @1) @1) (mod @0 @1))
> >>    @0))
> >>
> >> pattern?
> >>
> >> +/* x / y * y == x -> x % y == 0.  */
> >> +(simplify
> >> +  (eq (mult (trunc_div @0 @1) @1) @0)
> >> +  (eq (trunc_mod @0 @1) { build_zero_cst TREE_TYPE(@0); }))
> >>
> >> there are parens missing around the TREE_TYPE (@0), how did you test
> >> the patch?  You probably want :s on the trunc_div and as Andrew said
> >> :c on the eq and the mult.
> >
> >
> > I made those changes to the rule. The rule worked without the
> parentheses, which is probably why I didn't notice they were missing.
> Attached is an updated patch file.
>
> +/* x / y * y == x -> x % y == 0.  */
> +(simplify
> +  (eq:c (mult:c (trunc_div:s @0 @1) @1) @0)
> +  (if (TREE_CODE (TREE_TYPE (@0)) != COMPLEX_TYPE
> +       && TREE_CODE (TREE_TYPE (@1)) != COMPLEX_TYPE)
>
> Testing this only for @0 is enough, we don't allow mixed types for
> trunc_div or mult.
>
> +    (eq (trunc_mod @0 @1) { build_zero_cst (TREE_TYPE(@0)); })))
>
> space before (@0) in 'TREE_TYPE(@0)'
>
> OK with those changes.
>
> Thanks,
> Richard.
>
>
>
> > Thanks
> > -Sam
> >
> >>
> >> Richard.
> >>
> >> > Thanks
> >> > -Sam
> >> >
> >> >
> >> > > For vector try (which works for both the C and C++ front-end):
> >> > > #define vector __attribute__((vector_size(4*sizeof(int)) ))
> >> > > vector int f(vector int x, vector int y)
> >> > > {
> >> > >   return x == x / y * y;
> >> > > }
> >> > >
> >> > > That is for the vector case, == still returns a vector type.
> >> > >
> >> > > Thanks,
> >> > > Andrew Pinski
> >> > >
> >> > > >
> >> > > > Thanks
> >> > > > -Sam
> >> > > >
> >> > > >> Thanks,
> >> > > >> Andrew Pinski
> >> > > >>
> >> > > >> > diff --git a/gcc/testsuite/gcc.dg/pr104992-1.c
> >> > > b/gcc/testsuite/gcc.dg/pr104992-1.c
> >> > > >> > new file mode 100644
> >> > > >> > index 00000000000..a80e5e180ce
> >> > > >> > --- /dev/null
> >> > > >> > +++ b/gcc/testsuite/gcc.dg/pr104992-1.c
> >> > > >> > @@ -0,0 +1,30 @@
> >> > > >> > +/* PR tree-optimization/104992 */
> >> > > >> > +/* { dg-do run } */
> >> > > >> > +/* { dg-options "-O2"} */
> >> > > >> > +
> >> > > >> > +#include "pr104992.c"
> >> > > >> > +
> >> > > >> > +int main () {
> >> > > >> > +
> >> > > >> > +    /* Should be true.  */
> >> > > >> > +    if (!foo(6, 3)
> >> > > >> > +        || !bar(12, 2)
> >> > > >> > +        || !baz(34, 17)
> >> > > >> > +        || !qux(50, 10)
> >> > > >> > +        || !fred(16, 8)
> >> > > >> > +        || !baz(-9, 3)
> >> > > >> > +        || !baz(9, -3)
> >> > > >> > +        || !baz(-9, -3)
> >> > > >> > +        ) {
> >> > > >> > +            __builtin_abort();
> >> > > >> > +         }
> >> > > >> > +
> >> > > >> > +    /* Should be false.  */
> >> > > >> > +    if (foo(5, 30)
> >> > > >> > +        || bar(72, 27)
> >> > > >> > +        || baz(42, 15)) {
> >> > > >> > +            __builtin_abort();
> >> > > >> > +        }
> >> > > >> > +
> >> > > >> > +    return 0;
> >> > > >> > +}
> >> > > >> > diff --git a/gcc/testsuite/gcc.dg/pr104992.c
> >> > > b/gcc/testsuite/gcc.dg/pr104992.c
> >> > > >> > new file mode 100644
> >> > > >> > index 00000000000..b4b0ca53118
> >> > > >> > --- /dev/null
> >> > > >> > +++ b/gcc/testsuite/gcc.dg/pr104992.c
> >> > > >> > @@ -0,0 +1,35 @@
> >> > > >> > +/* PR tree-optimization/104992 */
> >> > > >> > +/* { dg-do compile } */
> >> > > >> > +/* { dg-options "-O2 -fdump-tree-optimized" } */
> >> > > >> > +
> >> > > >> > +/* Form from PR.  */
> >> > > >> > +__attribute__((noipa)) unsigned foo(unsigned x, unsigned y)
> >> > > >> > +{
> >> > > >> > +    return x / y * y == x;
> >> > > >> > +}
> >> > > >> > +
> >> > > >> > +__attribute__((noipa)) unsigned bar(unsigned x, unsigned y) {
> >> > > >> > +    return x == x / y * y;
> >> > > >> > +}
> >> > > >> > +
> >> > > >> > +/* Signed test case.  */
> >> > > >> > +__attribute__((noipa)) unsigned baz (int x, int y) {
> >> > > >> > +    return x / y * y == x;
> >> > > >> > +}
> >> > > >> > +
> >> > > >> > +/* Changed order.  */
> >> > > >> > +__attribute__((noipa)) unsigned qux (unsigned x, unsigned y) {
> >> > > >> > +    return y * (x / y) == x;
> >> > > >> > +}
> >> > > >> > +
> >> > > >> > +/* Wrong order.  */
> >> > > >> > +__attribute__((noipa)) unsigned fred (unsigned x, unsigned y)
> {
> >> > > >> > +    return y * x / y == x;
> >> > > >> > +}
> >> > > >> > +
> >> > > >> > +/* Wrong pattern.  */
> >> > > >> > +__attribute__((noipa)) unsigned waldo (unsigned x, unsigned y,
> >> > > unsigned z) {
> >> > > >> > +    return x / y * z == x;
> >> > > >> > +}
> >> > > >> > +
> >> > > >> > +/* { dg-final {scan-tree-dump-times " % " 4 "optimized" } } */
> >> > > >> >
> >> > > >> > base-commit: 633e9920589ddfaf2d6da1c24ce99b18a2638db4
> >> > > >> > --
> >> > > >> > 2.31.1
> >> > > >> >
> >> > > >>
> >> > >
> >> > >
> >>
>
>