The following plugs a hole with computing whether a SLP node has any
pattern stmts which is important to know when we want to replace it
by a CTOR from external defs.
Bootstrapped and tested on x86_64-unknown-linux-gnu, pushed.
PR tree-optimization/114799
* tree-vect-slp.cc (vect_get_and_check_slp_defs): Properly
update ->any_pattern when swapping operands.
* gcc.dg/vect/bb-slp-pr114799.c: New testcase.
---
gcc/testsuite/gcc.dg/vect/bb-slp-pr114799.c | 16 ++++++++++++++++
gcc/tree-vect-slp.cc | 6 ++++++
2 files changed, 22 insertions(+)
create mode 100644 gcc/testsuite/gcc.dg/vect/bb-slp-pr114799.c
diff --git a/gcc/testsuite/gcc.dg/vect/bb-slp-pr114799.c
b/gcc/testsuite/gcc.dg/vect/bb-slp-pr114799.c
new file mode 100644
index 00000000000..70572fe703b
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/vect/bb-slp-pr114799.c
@@ -0,0 +1,16 @@
+/* { dg-do compile } */
+/* { dg-additional-options "-fno-tree-forwprop" } */
+
+unsigned long x;
+unsigned char y;
+
+void
+foo (void)
+{
+ unsigned long tt = y;
+ tt+=255;
+ unsigned short t1 = tt;
+ t1 = 254 - t1;
+ tt += ((unsigned long)t1);
+ x = tt;
+}
diff --git a/gcc/tree-vect-slp.cc b/gcc/tree-vect-slp.cc
index 109f318c7d6..3eb326d20b5 100644
--- a/gcc/tree-vect-slp.cc
+++ b/gcc/tree-vect-slp.cc
@@ -888,6 +888,12 @@ vect_get_and_check_slp_defs (vec_info *vinfo, unsigned
char swap,
(*oprnds_info)[i+1]->def_stmts[stmt_num]);
std::swap ((*oprnds_info)[i]->ops[stmt_num],
(*oprnds_info)[i+1]->ops[stmt_num]);
+ /* After swapping some operands we lost track whether an
+ operand has any pattern defs so be conservative here. */
+ if ((*oprnds_info)[i]->any_pattern
+ || (*oprnds_info)[i+1]->any_pattern)
+ (*oprnds_info)[i]->any_pattern
+ = (*oprnds_info)[i+1]->any_pattern = true;
swapped = true;
continue;
}
--
2.35.3
