diff mbox series

Add a != MIN/MAX_VALUE_CST ? CST-+1 : a to minmax_from_comparison

Message ID 20230508052625.1185434-1-apinski@marvell.com
State Accepted
Headers
Series Add a != MIN/MAX_VALUE_CST ? CST-+1 : a to minmax_from_comparison |

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Context Check Description
snail/gcc-patch-check success Github commit url

Commit Message

Andrew Pinski May 8, 2023, 5:26 a.m. UTC 
  This patch adds the support for match that was implemented for PR 87913 in phiopt.
It implements it by adding support to minmax_from_comparison for the check.
It uses the range information if available which allows to produce MIN/MAX expression
when comparing against the lower/upper bound of the range instead of lower/upper
of the type.

minmax-20.c is the new testcase which tests the ranges part.

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

gcc/ChangeLog:

	* fold-const.cc (minmax_from_comparison): Add support for NE_EXPR.
	* match.pd ((cond (cmp (convert1? x) c1) (convert2? x) c2) pattern):
	Add ne as a possible cmp.
	((a CMP b) ? minmax<a, c> : minmax<b, c> pattern): Likewise.

gcc/testsuite/ChangeLog:

	* gcc.dg/tree-ssa/minmax-20.c: New test.
---
 gcc/fold-const.cc                         | 26 +++++++++++++++++++++++
 gcc/match.pd                              |  4 ++--
 gcc/testsuite/gcc.dg/tree-ssa/minmax-20.c | 12 +++++++++++
 3 files changed, 40 insertions(+), 2 deletions(-)
 create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/minmax-20.c

Comments

Richard Biener May 30, 2023, 9:32 a.m. UTC | #1 
On Mon, May 8, 2023 at 7:27 AM Andrew Pinski via Gcc-patches
<gcc-patches@gcc.gnu.org> wrote:
>
> This patch adds the support for match that was implemented for PR 87913 in phiopt.
> It implements it by adding support to minmax_from_comparison for the check.
> It uses the range information if available which allows to produce MIN/MAX expression
> when comparing against the lower/upper bound of the range instead of lower/upper
> of the type.
>
> minmax-20.c is the new testcase which tests the ranges part.
>
> OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions.

OK.

> gcc/ChangeLog:
>
>         * fold-const.cc (minmax_from_comparison): Add support for NE_EXPR.
>         * match.pd ((cond (cmp (convert1? x) c1) (convert2? x) c2) pattern):
>         Add ne as a possible cmp.
>         ((a CMP b) ? minmax<a, c> : minmax<b, c> pattern): Likewise.
>
> gcc/testsuite/ChangeLog:
>
>         * gcc.dg/tree-ssa/minmax-20.c: New test.
> ---
>  gcc/fold-const.cc                         | 26 +++++++++++++++++++++++
>  gcc/match.pd                              |  4 ++--
>  gcc/testsuite/gcc.dg/tree-ssa/minmax-20.c | 12 +++++++++++
>  3 files changed, 40 insertions(+), 2 deletions(-)
>  create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/minmax-20.c
>
> diff --git a/gcc/fold-const.cc b/gcc/fold-const.cc
> index db54bfc5662..d90671b9975 100644
> --- a/gcc/fold-const.cc
> +++ b/gcc/fold-const.cc
> @@ -173,6 +173,19 @@ minmax_from_comparison (tree_code cmp, tree exp0, tree exp1, tree exp2, tree exp
>           /* X > Y - 1 equals to X >= Y.  */
>           if (cmp == GT_EXPR)
>             code = GE_EXPR;
> +         /* a != MIN_RANGE<a> ? a : MIN_RANGE<a>+1 -> MAX_EXPR<MIN_RANGE<a>+1, a> */
> +         if (cmp == NE_EXPR && TREE_CODE (exp0) == SSA_NAME)
> +           {
> +             value_range r;
> +             get_range_query (cfun)->range_of_expr (r, exp0);
> +             if (r.undefined_p ())
> +               r.set_varying (TREE_TYPE (exp0));
> +
> +             widest_int min = widest_int::from (r.lower_bound (),
> +                                                TYPE_SIGN (TREE_TYPE (exp0)));
> +             if (min == wi::to_widest (exp1))
> +               code = MAX_EXPR;
> +           }
>         }
>        if (wi::to_widest (exp1) == (wi::to_widest (exp3) + 1))
>         {
> @@ -182,6 +195,19 @@ minmax_from_comparison (tree_code cmp, tree exp0, tree exp1, tree exp2, tree exp
>           /* X >= Y + 1 equals to X > Y.  */
>           if (cmp == GE_EXPR)
>           code = GT_EXPR;
> +         /* a != MAX_RANGE<a> ? a : MAX_RANGE<a>-1 -> MIN_EXPR<MIN_RANGE<a>-1, a> */
> +         if (cmp == NE_EXPR && TREE_CODE (exp0) == SSA_NAME)
> +           {
> +             value_range r;
> +             get_range_query (cfun)->range_of_expr (r, exp0);
> +             if (r.undefined_p ())
> +               r.set_varying (TREE_TYPE (exp0));
> +
> +             widest_int max = widest_int::from (r.upper_bound (),
> +                                                TYPE_SIGN (TREE_TYPE (exp0)));
> +             if (max == wi::to_widest (exp1))
> +               code = MIN_EXPR;
> +           }
>         }
>      }
>    if (code != ERROR_MARK
> diff --git a/gcc/match.pd b/gcc/match.pd
> index a55ede838cd..95f7e9a6abc 100644
> --- a/gcc/match.pd
> +++ b/gcc/match.pd
> @@ -4751,7 +4751,7 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
>
>     Case 2)
>     (cond (eq (convert1? x) c1) (convert2? x) c2) -> (cond (eq x c1) c1 c2).  */
> -(for cmp (lt le gt ge eq)
> +(for cmp (lt le gt ge eq ne)
>   (simplify
>    (cond (cmp (convert1? @1) INTEGER_CST@3) (convert2? @1) INTEGER_CST@2)
>    (with
> @@ -4942,7 +4942,7 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
>  /* Optimize (a CMP b) ? minmax<a, c> : minmax<b, c>
>     to minmax<min/max<a, b>, c> */
>  (for minmax (min max)
> - (for cmp (lt le gt ge)
> + (for cmp (lt le gt ge ne)
>    (simplify
>     (cond (cmp @1 @3) (minmax:c @1 @4) (minmax:c @2 @4))
>     (with
> diff --git a/gcc/testsuite/gcc.dg/tree-ssa/minmax-20.c b/gcc/testsuite/gcc.dg/tree-ssa/minmax-20.c
> new file mode 100644
> index 00000000000..481c375f5f9
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/tree-ssa/minmax-20.c
> @@ -0,0 +1,12 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O2 -fdump-tree-phiopt2" } */
> +
> +int f(int num)
> +{
> +  if (num < 3) __builtin_unreachable();
> +  return num != 3 ?  num : 4;
> +}
> +
> +/* In phiopt2 with the range information, this should be turned into
> +   a MAX_EXPR.  */
> +/* { dg-final { scan-tree-dump-times "MAX_EXPR" 1 "phiopt2" } } */
> --
> 2.31.1
>
diff mbox series

Patch

diff --git a/gcc/fold-const.cc b/gcc/fold-const.cc
index db54bfc5662..d90671b9975 100644
--- a/gcc/fold-const.cc
+++ b/gcc/fold-const.cc
@@ -173,6 +173,19 @@  minmax_from_comparison (tree_code cmp, tree exp0, tree exp1, tree exp2, tree exp
 	  /* X > Y - 1 equals to X >= Y.  */
 	  if (cmp == GT_EXPR)
 	    code = GE_EXPR;
+	  /* a != MIN_RANGE<a> ? a : MIN_RANGE<a>+1 -> MAX_EXPR<MIN_RANGE<a>+1, a> */
+	  if (cmp == NE_EXPR && TREE_CODE (exp0) == SSA_NAME)
+	    {
+	      value_range r;
+	      get_range_query (cfun)->range_of_expr (r, exp0);
+	      if (r.undefined_p ())
+		r.set_varying (TREE_TYPE (exp0));
+
+	      widest_int min = widest_int::from (r.lower_bound (),
+						 TYPE_SIGN (TREE_TYPE (exp0)));
+	      if (min == wi::to_widest (exp1))
+		code = MAX_EXPR;
+	    }
 	}
       if (wi::to_widest (exp1) == (wi::to_widest (exp3) + 1))
 	{
@@ -182,6 +195,19 @@  minmax_from_comparison (tree_code cmp, tree exp0, tree exp1, tree exp2, tree exp
 	  /* X >= Y + 1 equals to X > Y.  */
 	  if (cmp == GE_EXPR)
 	  code = GT_EXPR;
+	  /* a != MAX_RANGE<a> ? a : MAX_RANGE<a>-1 -> MIN_EXPR<MIN_RANGE<a>-1, a> */
+	  if (cmp == NE_EXPR && TREE_CODE (exp0) == SSA_NAME)
+	    {
+	      value_range r;
+	      get_range_query (cfun)->range_of_expr (r, exp0);
+	      if (r.undefined_p ())
+		r.set_varying (TREE_TYPE (exp0));
+
+	      widest_int max = widest_int::from (r.upper_bound (),
+						 TYPE_SIGN (TREE_TYPE (exp0)));
+	      if (max == wi::to_widest (exp1))
+		code = MIN_EXPR;
+	    }
 	}
     }
   if (code != ERROR_MARK
diff --git a/gcc/match.pd b/gcc/match.pd
index a55ede838cd..95f7e9a6abc 100644
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -4751,7 +4751,7 @@  DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
 
    Case 2)
    (cond (eq (convert1? x) c1) (convert2? x) c2) -> (cond (eq x c1) c1 c2).  */
-(for cmp (lt le gt ge eq)
+(for cmp (lt le gt ge eq ne)
  (simplify
   (cond (cmp (convert1? @1) INTEGER_CST@3) (convert2? @1) INTEGER_CST@2)
   (with
@@ -4942,7 +4942,7 @@  DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
 /* Optimize (a CMP b) ? minmax<a, c> : minmax<b, c>
    to minmax<min/max<a, b>, c> */
 (for minmax (min max)
- (for cmp (lt le gt ge)
+ (for cmp (lt le gt ge ne)
   (simplify
    (cond (cmp @1 @3) (minmax:c @1 @4) (minmax:c @2 @4))
    (with
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/minmax-20.c b/gcc/testsuite/gcc.dg/tree-ssa/minmax-20.c
new file mode 100644
index 00000000000..481c375f5f9
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/minmax-20.c
@@ -0,0 +1,12 @@ 
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-phiopt2" } */
+
+int f(int num)
+{
+  if (num < 3) __builtin_unreachable();
+  return num != 3 ?  num : 4;
+}
+
+/* In phiopt2 with the range information, this should be turned into
+   a MAX_EXPR.  */
+/* { dg-final { scan-tree-dump-times "MAX_EXPR" 1 "phiopt2" } } */