When I added this pattern in r14-337-gc43819a9b4cd, I had missed the :c on the
cmp
part of the pattern meaning there might be some missing optimizations happening.
The testcase shows an example of the missed optmization.
Committed as obvious after a bootstrap/test on x86_64-linux-gnu.
PR tree-optimization/111348
gcc/ChangeLog:
* match.pd (`(a CMP b) ? minmax<a, c> : minmax<b, c>`): Add :c on
the cmp part of the pattern.
gcc/testsuite/ChangeLog:
* gcc.dg/tree-ssa/minmax-26.c: New test.
---
gcc/match.pd | 2 +-
gcc/testsuite/gcc.dg/tree-ssa/minmax-26.c | 22 ++++++++++++++++++++++
2 files changed, 23 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/minmax-26.c
diff --git a/gcc/match.pd b/gcc/match.pd
index 209b0599382..e96e385c6fa 100644
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -5417,7 +5417,7 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
(for minmax (min max)
(for cmp (lt le gt ge ne)
(simplify
- (cond (cmp @1 @3) (minmax:c @1 @4) (minmax:c @2 @4))
+ (cond (cmp:c @1 @3) (minmax:c @1 @4) (minmax:c @2 @4))
(with
{
tree_code code = minmax_from_comparison (cmp, @1, @2, @1, @3);
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/minmax-26.c
b/gcc/testsuite/gcc.dg/tree-ssa/minmax-26.c
new file mode 100644
index 00000000000..e4b7412e766
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/minmax-26.c
@@ -0,0 +1,22 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized -fdump-tree-original" } */
+/* PR tree-optimization/111348 */
+
+int test1(int a, int b, int c)
+{
+ return (a > b) ? ((a > c) ? a : c) : ((b > c) ? b : c);
+}
+
+
+int test1_(int a, int b, int c)
+{
+ return (b < a) ? ((a > c) ? a : c) : ((b > c) ? b : c);
+}
+
+/* test1 and test1_ should be able to optimize to `MAX_EXPR <MAX_EXPR <a, b>,
c>;` during fold. */
+/* { dg-final { scan-tree-dump-times "MAX_EXPR <MAX_EXPR <a, b>, c>" 2
"original" } } */
+/* { dg-final { scan-tree-dump-not "b > a" "original" } } */
+/* { dg-final { scan-tree-dump-not "a > b" "original" } } */
+/* { dg-final { scan-tree-dump-times "MAX_EXPR " 4 "optimized" } } */
+/* { dg-final { scan-tree-dump-not "if " "optimized" } } */
+
--
2.31.1
