https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67842
Bug ID: 67842
Summary: Incorrect check in sese.h:bb_in_region
Product: gcc
Version: 6.0
Status: UNCONFIRMED
Keywords: ice-checking
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: miyuki at gcc dot gnu.org
Target Milestone: ---
>From discussion on the mailing list:
https://gcc.gnu.org/ml/gcc-patches/2015-09/msg00615.html
The function bb_in_region contains the following check guarded by
ENABLE_CHECKING:
edge e;
edge_iterator ei;
/* Check that there are no edges coming in the region: all the
predecessors of EXIT are dominated by ENTRY. */
FOR_EACH_EDGE (e, ei, exit->preds)
dominated_by_p (CDI_DOMINATORS, e->src, entry);
dominated_by_p is a pure function, so the check has no effect. If it is changed
to
gcc_assert (dominated_by_p (CDI_DOMINATORS, e->src, entry));
It starts to ICE on several testcases, for example gcc.dg/graphite/block-1.c.
