The following testcase ICEs since r10-3199.
There is a switch with default label, where the controlling expression has
range just 0..7 and there are case labels for all those 8 values, but
nothing has yet optimized away the default.
Since r10-3199, set_switch_stmt_execution_predicate sets the switch to
default label's edge's predicate to a false predicate and then
compute_bb_predicates propagates the predicates through the cfg, but false
predicates aren't really added. The caller of compute_bb_predicates
in one place handles NULL bb->aux as false predicate:
if (fbi.info)
{
if (bb->aux)
bb_predicate = *(predicate *) bb->aux;
else
bb_predicate = false;
}
else
bb_predicate = true;
but then in two further spots that the patch below is changing
it assumes bb->aux must be non-NULL. Those two spots are guarded by a
condition that is only true if fbi.info is non-NULL, so I think the right
fix is to treat NULL aux as false predicate in those spots too.
2020-07-13 Jakub Jelinek <jakub@redhat.com>
PR ipa/96130
* ipa-fnsummary.c (analyze_function_body): Treat NULL bb->aux
as false predicate.
* gcc.dg/torture/pr96130.c: New test.
(cherry picked from commit 776e48e0931db69f158f40e5cb8e15463d879a42)
