As noted in PR 85354, we cannot simply invoke cfg_cleanup after dominators are
computed, because they may become invalid but neither freed nor recomputed, so
this trips checking in flow_loops_find.
We can move cleanup_cfg earlier (and run it for all sel-sched invocations, not
only when pipelining).
Bootstrapped/regtested on x86_64 and ppc64 (my previous testing missed this
issue: the testcase requires graphite, but libisl wasn't present).
PR rtl-optimization/85354
* sel-sched-ir.c (sel_init_pipelining): Move cfg_cleanup call...
* sel-sched.c (sel_global_init): ... here.
diff --git a/gcc/sel-sched-ir.c b/gcc/sel-sched-ir.c
index 50a7daafba6..ee970522890 100644
--- a/gcc/sel-sched-ir.c
+++ b/gcc/sel-sched-ir.c
@@ -30,7 +30,6 @@ along with GCC; see the file COPYING3. If not see
#include "cfgrtl.h"
#include "cfganal.h"
#include "cfgbuild.h"
-#include "cfgcleanup.h"
#include "insn-config.h"
#include "insn-attr.h"
#include "recog.h"
@@ -6122,9 +6121,6 @@ make_regions_from_loop_nest (struct loop *loop)
void
sel_init_pipelining (void)
{
- /* Remove empty blocks: their presence can break assumptions elsewhere,
- e.g. the logic to invoke update_liveness_on_insn in sel_region_init. */
- cleanup_cfg (0);
/* Collect loop information to be used in outer loops pipelining. */
loop_optimizer_init (LOOPS_HAVE_PREHEADERS
| LOOPS_HAVE_FALLTHRU_PREHEADERS
diff --git a/gcc/sel-sched.c b/gcc/sel-sched.c
index cd29df35666..59762964c6e 100644
--- a/gcc/sel-sched.c
+++ b/gcc/sel-sched.c
@@ -28,6 +28,7 @@ along with GCC; see the file COPYING3. If not see
#include "tm_p.h"
#include "regs.h"
#include "cfgbuild.h"
+#include "cfgcleanup.h"
#include "insn-config.h"
#include "insn-attr.h"
#include "params.h"
@@ -7661,6 +7662,10 @@ sel_sched_region (int rgn)
static void
sel_global_init (void)
{
+ /* Remove empty blocks: their presence can break assumptions elsewhere,
+ e.g. the logic to invoke update_liveness_on_insn in sel_region_init. */
+ cleanup_cfg (0);
+
calculate_dominance_info (CDI_DOMINATORS);
alloc_sched_pools ();
