MATCH: [PR111346] `X CMP MINMAX` pattern missing :c on CMP
Checks
Commit Message
I noticed this while working on other MINMAX optimizations. It was
hard to find a simplified testcase though because it was dependent on
the ssa name versions. Adding the `:c` to cmp allows the pattern to
be match for the case where minmax as the first operand of the comparison
rather than the second.
Committed as obvious after a bootstrap/test on x86_64-linux-gnu.
PR tree-optimization/111346
gcc/ChangeLog:
* match.pd (`X CMP MINMAX`): Add `:c` on the cmp part
of the pattern
gcc/testsuite/ChangeLog:
* gcc.dg/tree-ssa/minmaxcmp-1.c: New test.
---
gcc/match.pd | 2 +-
gcc/testsuite/gcc.dg/tree-ssa/minmaxcmp-1.c | 39 +++++++++++++++++++++
2 files changed, 40 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/minmaxcmp-1.c
Comments
On 9/10/23 20:18, Andrew Pinski via Gcc-patches wrote:
> I noticed this while working on other MINMAX optimizations. It was
> hard to find a simplified testcase though because it was dependent on
> the ssa name versions. Adding the `:c` to cmp allows the pattern to
> be match for the case where minmax as the first operand of the comparison
> rather than the second.
>
> Committed as obvious after a bootstrap/test on x86_64-linux-gnu.
>
> PR tree-optimization/111346
>
> gcc/ChangeLog:
>
> * match.pd (`X CMP MINMAX`): Add `:c` on the cmp part
> of the pattern
>
> gcc/testsuite/ChangeLog:
>
> * gcc.dg/tree-ssa/minmaxcmp-1.c: New test.
OK
jeff
@@ -3942,7 +3942,7 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
(for minmax (min min max max )
cmp (ge lt le gt )
(simplify
- (cmp @0 (minmax:c @0 @1))
+ (cmp:c @0 (minmax:c @0 @1))
{ constant_boolean_node (cmp == GE_EXPR || cmp == LE_EXPR, type); } ))
/* Undo fancy ways of writing max/min or other ?: expressions, like
new file mode 100644
@@ -0,0 +1,39 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized -fdump-tree-original" } */
+/* PR tree-optimization/111346 */
+
+int f();
+int g();
+
+_Bool test1(int a, int b)
+{
+ return ((a > b) ? a : b) >= a; // return 1;
+}
+_Bool test1_(int a, int b)
+{
+ return a <= ((a > b) ? a : b); // return 1;
+}
+/* test1 and test1_ should be able to optimize to `return 1;` during fold. */
+/* { dg-final { scan-tree-dump-times "return 1;" 2 "original" } } */
+/* { dg-final { scan-tree-dump-not " MAX_EXPR " "original" } } */
+
+_Bool test2(int a, int b)
+{
+ a = f();
+ a = g();
+ int t = a;
+ if (t < b) t = b;
+ return t >= a; // return 1;
+}
+
+_Bool test2_(int a, int b)
+{
+ a = g();
+ int t = a;
+ if (t < b) t = b;
+ return t >= a; // return 1;
+}
+
+/* All of these should be optimized to just be the function calls and `return 1;` */
+/* { dg-final { scan-tree-dump-times "return 1;" 4 "optimized" } } */
+/* { dg-final { scan-tree-dump-not " MAX_EXPR " "optimized" } } */