[PATCH] MATCH: Port CLRSB part of builtin_zero_pattern

[PATCH] MATCH: Port CLRSB part of builtin_zero_pattern

[Andrew Pinski]

This ports the clrsb builtin part of builtin_zero_pattern
to match.pd. A simple pattern to port.

OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions.

gcc/ChangeLog:

	* match.pd (a != 0 ? CLRSB(a) : CST -> CLRSB(a)): New
	pattern.
---
 gcc/match.pd | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/gcc/match.pd b/gcc/match.pd
index 0e782cde71d..bf918ba70ce 100644
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -7787,6 +7787,14 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
   (cond (ne @0 integer_zerop@1) (func@4 (convert? @2)) integer_zerop@3)
   @4))
 
+/* a != 0 ? FUN(a) : CST -> Fun(a) for some CLRSB builtins
+   where CST is precision-1. */
+(for func (CLRSB)
+ (simplify
+  (cond (ne @0 integer_zerop@1) (func@5 (convert?@4 @2)) INTEGER_CST@3)
+  (if (wi::to_widest (@3) == TYPE_PRECISION (TREE_TYPE (@4)) - 1)
+   @5)))
+
 #if GIMPLE
 /* a != 0 ? CLZ(a) : CST -> .CLZ(a) where CST is the result of the internal function for 0. */
 (for func (CLZ)
-- 
2.31.1

Re: [PATCH] MATCH: Port CLRSB part of builtin_zero_pattern

[Richard Biener]

On Sun, Apr 30, 2023 at 11:13 PM Andrew Pinski via Gcc-patches
<gcc-patches@gcc.gnu.org> wrote:
>
> This ports the clrsb builtin part of builtin_zero_pattern
> to match.pd. A simple pattern to port.
>
> OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions.
>
> gcc/ChangeLog:
>
>         * match.pd (a != 0 ? CLRSB(a) : CST -> CLRSB(a)): New
>         pattern.
> ---
>  gcc/match.pd | 8 ++++++++
>  1 file changed, 8 insertions(+)
>
> diff --git a/gcc/match.pd b/gcc/match.pd
> index 0e782cde71d..bf918ba70ce 100644
> --- a/gcc/match.pd
> +++ b/gcc/match.pd
> @@ -7787,6 +7787,14 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
>    (cond (ne @0 integer_zerop@1) (func@4 (convert? @2)) integer_zerop@3)
>    @4))
>
> +/* a != 0 ? FUN(a) : CST -> Fun(a) for some CLRSB builtins
> +   where CST is precision-1. */
> +(for func (CLRSB)
> + (simplify
> +  (cond (ne @0 integer_zerop@1) (func@5 (convert?@4 @2)) INTEGER_CST@3)

As you don't seem to use @2 why not match (func@5 @4) only?

Otherwise LGTM.

> +  (if (wi::to_widest (@3) == TYPE_PRECISION (TREE_TYPE (@4)) - 1)
> +   @5)))
> +
>  #if GIMPLE
>  /* a != 0 ? CLZ(a) : CST -> .CLZ(a) where CST is the result of the internal function for 0. */
>  (for func (CLZ)
> --
> 2.31.1
>

Re: [PATCH] MATCH: Port CLRSB part of builtin_zero_pattern

[Andrew Pinski]

On Tue, May 2, 2023 at 5:24 AM Richard Biener via Gcc-patches
<gcc-patches@gcc.gnu.org> wrote:
>
> On Sun, Apr 30, 2023 at 11:13 PM Andrew Pinski via Gcc-patches
> <gcc-patches@gcc.gnu.org> wrote:
> >
> > This ports the clrsb builtin part of builtin_zero_pattern
> > to match.pd. A simple pattern to port.
> >
> > OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions.
> >
> > gcc/ChangeLog:
> >
> >         * match.pd (a != 0 ? CLRSB(a) : CST -> CLRSB(a)): New
> >         pattern.
> > ---
> >  gcc/match.pd | 8 ++++++++
> >  1 file changed, 8 insertions(+)
> >
> > diff --git a/gcc/match.pd b/gcc/match.pd
> > index 0e782cde71d..bf918ba70ce 100644
> > --- a/gcc/match.pd
> > +++ b/gcc/match.pd
> > @@ -7787,6 +7787,14 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
> >    (cond (ne @0 integer_zerop@1) (func@4 (convert? @2)) integer_zerop@3)
> >    @4))
> >
> > +/* a != 0 ? FUN(a) : CST -> Fun(a) for some CLRSB builtins
> > +   where CST is precision-1. */
> > +(for func (CLRSB)
> > + (simplify
> > +  (cond (ne @0 integer_zerop@1) (func@5 (convert?@4 @2)) INTEGER_CST@3)
>
> As you don't seem to use @2 why not match (func@5 @4) only?

Thanks for catching this, @2 should really have been @0, otherwise we
get the wrong answer in general.
I fixed the other patterns I just added for this same issue too.

This is what I committed instead:
/* a != 0 ? FUN(a) : CST -> Fun(a) for some CLRSB builtins
   where CST is precision-1. */
(for func (CLRSB)
 (simplify
  (cond (ne @0 integer_zerop@1) (func@4 (convert?@3 @0)) INTEGER_CST@2)
  (if (wi::to_widest (@2) == TYPE_PRECISION (TREE_TYPE (@3)) - 1)
   @4)))

Thanks,
Andrew

>
> Otherwise LGTM.
>
> > +  (if (wi::to_widest (@3) == TYPE_PRECISION (TREE_TYPE (@4)) - 1)
> > +   @5)))
> > +
> >  #if GIMPLE
> >  /* a != 0 ? CLZ(a) : CST -> .CLZ(a) where CST is the result of the internal function for 0. */
> >  (for func (CLZ)
> > --
> > 2.31.1
> >