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| author | Jan Hubicka <hubicka@gcc.gnu.org> | 2019-05-07 09:36:05 +0000 |
|---|---|---|
| committer | Jan Hubicka <hubicka@gcc.gnu.org> | 2019-05-07 09:36:05 +0000 |
| commit | 9edfa4c015a3ae0451a30259ef654c632f9f4ca5 (patch) | |
| tree | 85cfd477da08953247df27f386a476e664dd4d88 /gcc/tree-ssa-alias.c | |
| parent | fe26771191ab959eab1b92ac8a574a900a2a3f4c (diff) | |
| download | gcc-9edfa4c015a3ae0451a30259ef654c632f9f4ca5.zip gcc-9edfa4c015a3ae0451a30259ef654c632f9f4ca5.tar.gz gcc-9edfa4c015a3ae0451a30259ef654c632f9f4ca5.tar.bz2 | |
tree-ssa-alias.c (aliasing_component_refs_p): Continue looking for comparaible types in the second direction even if...
* tree-ssa-alias.c (aliasing_component_refs_p): Continue looking
for comparaible types in the second direction even if first one
hits incomparable type.
From-SVN: r270938
Diffstat (limited to 'gcc/tree-ssa-alias.c')
| -rw-r--r-- | gcc/tree-ssa-alias.c | 24 |
1 files changed, 13 insertions, 11 deletions
diff --git a/gcc/tree-ssa-alias.c b/gcc/tree-ssa-alias.c index 4d00d38..1947710 100644 --- a/gcc/tree-ssa-alias.c +++ b/gcc/tree-ssa-alias.c @@ -795,7 +795,7 @@ aliasing_component_refs_p (tree ref1, tree base1, base2; tree type1, type2; tree *refp; - int same_p; + int same_p, same_p2; /* Choose bases and base types to search for. */ base1 = ref1; @@ -814,10 +814,7 @@ aliasing_component_refs_p (tree ref1, && same_type_for_tbaa (TREE_TYPE (*refp), type1) == 0) refp = &TREE_OPERAND (*refp, 0); same_p = same_type_for_tbaa (TREE_TYPE (*refp), type1); - /* If we couldn't compare types we have to bail out. */ - if (same_p == -1) - return true; - else if (same_p == 1) + if (same_p == 1) { poly_int64 offadj, sztmp, msztmp; bool reverse; @@ -827,26 +824,31 @@ aliasing_component_refs_p (tree ref1, offset1 -= offadj; return ranges_maybe_overlap_p (offset1, max_size1, offset2, max_size2); } + /* If we didn't find a common base, try the other way around. */ refp = &ref1; while (handled_component_p (*refp) && same_type_for_tbaa (TREE_TYPE (*refp), type2) == 0) refp = &TREE_OPERAND (*refp, 0); - same_p = same_type_for_tbaa (TREE_TYPE (*refp), type2); - /* If we couldn't compare types we have to bail out. */ - if (same_p == -1) - return true; - else if (same_p == 1) + same_p2 = same_type_for_tbaa (TREE_TYPE (*refp), type2); + if (same_p2 == 1) { poly_int64 offadj, sztmp, msztmp; bool reverse; + get_ref_base_and_extent (*refp, &offadj, &sztmp, &msztmp, &reverse); offset1 -= offadj; get_ref_base_and_extent (base2, &offadj, &sztmp, &msztmp, &reverse); offset2 -= offadj; - return ranges_maybe_overlap_p (offset1, max_size1, offset2, max_size2); + return ranges_maybe_overlap_p (offset1, max_size1, + offset2, max_size2); } + /* In the remaining test we assume that there is no overlapping type + at all. So if we are unsure, we need to give up. */ + if (same_p == -1 || same_p2 == -1) + return true; + /* If we have two type access paths B1.path1 and B2.path2 they may only alias if either B1 is in B2.path2 or B2 is in B1.path1. But we can still have a path that goes B1.path1...B2.path2 with |