https://gcc.gnu.org/g:f3dde39e597f48832208f423fb20f29674ce49ae
commit r16-1409-gf3dde39e597f48832208f423fb20f29674ce49ae
Author: Jakub Jelinek <ja...@redhat.com>
Date: Wed Jun 11 07:03:04 2025 +0200
ranger: Handle the theoretical case of GIMPLE_COND with one succ edge
during expansion [PR120434]
On Tue, Jun 10, 2025 at 10:51:25AM -0400, Andrew MacLeod wrote:
> Edge range should be fine, and really that assert doesnt really need to be
> there.
>
> Where the issue could arise is in gimple-range-fold.cc in
> fold_using_range::range_of_range_op() where we see something like:
>
> else if (is_a<gcond *> (s) && gimple_bb (s))
> {
> basic_block bb = gimple_bb (s);
> edge e0 = EDGE_SUCC (bb, 0);
> edge e1 = EDGE_SUCC (bb, 1);
>
> if (!single_pred_p (e0->dest))
> e0 = NULL;
> if (!single_pred_p (e1->dest))
> e1 = NULL;
> src.register_outgoing_edges (as_a<gcond *> (s),
> as_a <irange> (r), e0, e1);
>
> Althogh, now that I look at it, it doesn't need much adjustment, just the
> expectation that there are 2 edges. I suppose EDGE_SUCC (bb, 1) cpould
> potentially trap if there is only one edge. we'd just have to guard it
and
> alloow for that case
This patch implements that.
2025-06-11 Jakub Jelinek <ja...@redhat.com>
PR middle-end/120434
* gimple-range-fold.cc: Include rtl.h.
(fold_using_range::range_of_range_op): Handle bb ending with
GIMPLE_COND during RTL expansion where there is only one succ
edge instead of two.
Diff:
---
gcc/gimple-range-fold.cc | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/gcc/gimple-range-fold.cc b/gcc/gimple-range-fold.cc
index aed5c7dc21eb..d18b37b33800 100644
--- a/gcc/gimple-range-fold.cc
+++ b/gcc/gimple-range-fold.cc
@@ -51,6 +51,7 @@ along with GCC; see the file COPYING3. If not see
#include "sreal.h"
#include "ipa-cp.h"
#include "ipa-prop.h"
+#include "rtl.h"
// Construct a fur_source, and set the m_query field.
fur_source::fur_source (range_query *q)
@@ -778,11 +779,14 @@ fold_using_range::range_of_range_op (vrange &r,
{
basic_block bb = gimple_bb (s);
edge e0 = EDGE_SUCC (bb, 0);
- edge e1 = EDGE_SUCC (bb, 1);
+ /* During RTL expansion one of the edges can be removed
+ if expansion proves the jump is unconditional. */
+ edge e1 = single_succ_p (bb) ? NULL : EDGE_SUCC (bb, 1);
+ gcc_checking_assert (e1 || currently_expanding_to_rtl);
if (!single_pred_p (e0->dest))
e0 = NULL;
- if (!single_pred_p (e1->dest))
+ if (e1 && !single_pred_p (e1->dest))
e1 = NULL;
src.register_outgoing_edges (as_a<gcond *> (s),
as_a <irange> (r), e0, e1);
