https://gcc.gnu.org/g:64a6c0d594c05f275de91df35047cffb3ccecf2f
commit r14-10394-g64a6c0d594c05f275de91df35047cffb3ccecf2f
Author: Richard Biener <rguent...@suse.de>
Date: Mon Jul 1 10:06:55 2024 +0200
tree-optimization/115723 - ICE with .COND_ADD reduction
The following fixes an ICE with a .COND_ADD discovered as reduction
even though its else value isn't the reduction chain link but a
constant. This would be wrong-code with --disable-checking I think.
PR tree-optimization/115723
* tree-vect-loop.cc (check_reduction_path): For a .COND_ADD
verify the else value also refers to the reduction chain op.
* gcc.dg/vect/pr115723.c: New testcase.
(cherry picked from commit 286cda3461d6f5ce7d911d3f26bd4975ea7ea11d)
Diff:
---
gcc/testsuite/gcc.dg/vect/pr115723.c | 25 +++++++++++++++++++++++++
gcc/tree-vect-loop.cc | 12 ++++++++----
2 files changed, 33 insertions(+), 4 deletions(-)
diff --git a/gcc/testsuite/gcc.dg/vect/pr115723.c
b/gcc/testsuite/gcc.dg/vect/pr115723.c
new file mode 100644
index 000000000000..b98b29d48702
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/vect/pr115723.c
@@ -0,0 +1,25 @@
+/* { dg-additional-options "-ffast-math -fno-unsafe-math-optimizations" } */
+
+#include "tree-vect.h"
+
+double __attribute__((noipa))
+foo (double *x, double *y, int n)
+{
+ double res = 0.;
+ for (int i = 0; i < n; ++i)
+ if (y[i] > 0.)
+ res += x[i];
+ else
+ res = 64.;
+ return res;
+}
+
+double y[16] = { 1., 1., 1., 1., 0., 1., 1., 1.,
+ 1., 1., 1., 1., 1., 1., 1., 1. };
+int main ()
+{
+ check_vect ();
+ if (foo (y, y, 16) != 64. + 11.)
+ abort ();
+ return 0;
+}
diff --git a/gcc/tree-vect-loop.cc b/gcc/tree-vect-loop.cc
index 29c03c246d45..832399f7e9d7 100644
--- a/gcc/tree-vect-loop.cc
+++ b/gcc/tree-vect-loop.cc
@@ -4161,15 +4161,19 @@ pop:
FOR_EACH_IMM_USE_STMT (op_use_stmt, imm_iter, op.ops[opi])
{
- /* In case of a COND_OP (mask, op1, op2, op1) reduction we might have
- op1 twice (once as definition, once as else) in the same operation.
- Allow this. */
+ /* In case of a COND_OP (mask, op1, op2, op1) reduction we should
+ have op1 twice (once as definition, once as else) in the same
+ operation. Enforce this. */
if (cond_fn_p && op_use_stmt == use_stmt)
{
gcall *call = as_a<gcall *> (use_stmt);
unsigned else_pos
= internal_fn_else_index (internal_fn (op.code));
-
+ if (gimple_call_arg (call, else_pos) != op.ops[opi])
+ {
+ fail = true;
+ break;
+ }
for (unsigned int j = 0; j < gimple_call_num_args (call); ++j)
{
if (j == else_pos)
