diff options
author | Andrew MacLeod <amacleod@redhat.com> | 2023-03-23 10:28:34 -0400 |
---|---|---|
committer | Andrew MacLeod <amacleod@redhat.com> | 2023-03-24 09:11:09 -0400 |
commit | 0409aa5a2de9ce3164933814a4a7adc91f6acb96 (patch) | |
tree | 0cd410bc9183c6ceaaccf083f61c04d7b60fd52f /gcc/gimple-range-cache.cc | |
parent | ed626f18b189920aeed9974aded3f9cb6f25b543 (diff) | |
download | gcc-0409aa5a2de9ce3164933814a4a7adc91f6acb96.zip gcc-0409aa5a2de9ce3164933814a4a7adc91f6acb96.tar.gz gcc-0409aa5a2de9ce3164933814a4a7adc91f6acb96.tar.bz2 |
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.cc | 5 |
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); } |