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authorAndrew MacLeod <amacleod@redhat.com>2023-03-23 10:28:34 -0400
committerAndrew MacLeod <amacleod@redhat.com>2023-03-24 09:11:09 -0400
commit0409aa5a2de9ce3164933814a4a7adc91f6acb96 (patch)
tree0cd410bc9183c6ceaaccf083f61c04d7b60fd52f /gcc/gimple-range-cache.cc
parented626f18b189920aeed9974aded3f9cb6f25b543 (diff)
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Ranger cache dominator queries should ignore backedges.
When querying dominators for cache values, ignore back edges in read-only mode. PR tree-optimization/109238 gcc/ * gimple-range-cache.cc (ranger_cache::resolve_dom): Ignore predecessors which this block dominates. gcc/testsuite/ * gcc.dg/pr109238.c: New.
Diffstat (limited to 'gcc/gimple-range-cache.cc')
-rw-r--r--gcc/gimple-range-cache.cc5
1 files changed, 5 insertions, 0 deletions
diff --git a/gcc/gimple-range-cache.cc b/gcc/gimple-range-cache.cc
index cc56fd4..6a098d8 100644
--- a/gcc/gimple-range-cache.cc
+++ b/gcc/gimple-range-cache.cc
@@ -1404,6 +1404,11 @@ ranger_cache::resolve_dom (vrange &r, tree name, basic_block bb)
Value_Range er (TREE_TYPE (name));
FOR_EACH_EDGE (e, ei, bb->preds)
{
+ // If the predecessor is dominated by this block, then there is a back
+ // edge, and won't provide anything useful. We'll actually end up with
+ // VARYING as we will not resolve this node.
+ if (dominated_by_p (CDI_DOMINATORS, e->src, bb))
+ continue;
edge_range (er, e, name, RFD_READ_ONLY);
r.union_ (er);
}