Hi,
this patch fixes ICE in estimate_bb_frequencies which triggers because we forget
to compute probability for blocks whose count is earlier statically determined
to be
0.
Bootstrapped/regtested x86_64-linux, will commit it shortly.
Honza
PR middle-end/81462
* predict.c (set_even_probabilities): Cleanup; do not affect
probabilities that are already known.
(combine_predictions_for_bb): Call even when count is set.
* g++.dg/torture/pr81462.C: New testcase.
Index: predict.c
===================================================================
--- predict.c (revision 250295)
+++ predict.c (working copy)
@@ -817,16 +817,25 @@ static void
set_even_probabilities (basic_block bb,
hash_set<edge> *unlikely_edges = NULL)
{
- unsigned nedges = 0;
+ unsigned nedges = 0, unlikely_count = 0;
edge e = NULL;
edge_iterator ei;
+ profile_probability all = profile_probability::always ();
FOR_EACH_EDGE (e, ei, bb->succs)
- if (!unlikely_executed_edge_p (e))
- nedges ++;
+ if (e->probability.initialized_p ())
+ all -= e->probability;
+ else if (!unlikely_executed_edge_p (e))
+ {
+ nedges ++;
+ if (unlikely_edges != NULL && unlikely_edges->contains (e))
+ {
+ all -= profile_probability::very_unlikely ();
+ unlikely_count++;
+ }
+ }
/* Make the distribution even if all edges are unlikely. */
- unsigned unlikely_count = unlikely_edges ? unlikely_edges->elements () : 0;
if (unlikely_count == nedges)
{
unlikely_edges = NULL;
@@ -836,13 +845,14 @@ set_even_probabilities (basic_block bb,
unsigned c = nedges - unlikely_count;
FOR_EACH_EDGE (e, ei, bb->succs)
- if (!unlikely_executed_edge_p (e))
+ if (e->probability.initialized_p ())
+ ;
+ else if (!unlikely_executed_edge_p (e))
{
if (unlikely_edges != NULL && unlikely_edges->contains (e))
e->probability = profile_probability::very_unlikely ();
else
- e->probability = profile_probability::guessed_always ()
- .apply_scale (1, c);
+ e->probability = all.apply_scale (1, c).guessed ();
}
else
e->probability = profile_probability::never ();
@@ -1151,7 +1161,7 @@ combine_predictions_for_bb (basic_block
if (pred->ep_probability <= PROB_VERY_UNLIKELY)
unlikely_edges.add (pred->ep_edge);
- if (!bb->count.initialized_p () && !dry_run)
+ if (!dry_run)
set_even_probabilities (bb, &unlikely_edges);
clear_bb_predictions (bb);
if (dump_file)
Index: testsuite/g++.dg/torture/pr81462.C
===================================================================
--- testsuite/g++.dg/torture/pr81462.C (revision 0)
+++ testsuite/g++.dg/torture/pr81462.C (working copy)
@@ -0,0 +1,17 @@
+// { dg-do compile }
+// { dg-options "-O1 -fno-ipa-pure-const" }
+struct B {
+ B* self;
+ B() : self( this ) { self->f(); }
+ virtual void f() = 0;
+ };
+
+ struct D : B
+ {
+ void f() {}
+ };
+
+ int main()
+ {
+ D d;
+ }
