This picks the ptr_derefs_may_alias_p fix from the PR99954 fix
which said: This makes us run into a latent issue in
ptr_deref_may_alias_decl_p when the pointer is something like &MEM[0].a
in which case we fail to handle non-SSA name pointers. Add code
similar to what we have in ptr_derefs_may_alias_p.
Bootstrap/regtest running on x86_64-unknown-linux-gnu.
PR tree-optimization/120156
* tree-ssa-alias.cc (ptr_deref_may_alias_decl_p): Verify
the pointer is an SSA name.
(cherry picked from commit c290e6a0b7a9de5692963affc6627a4af7dc2411)
---
gcc/tree-ssa-alias.cc | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/gcc/tree-ssa-alias.cc b/gcc/tree-ssa-alias.cc
index 790447b3840..0a1f3d257a4 100644
--- a/gcc/tree-ssa-alias.cc
+++ b/gcc/tree-ssa-alias.cc
@@ -295,6 +295,11 @@ ptr_deref_may_alias_decl_p (tree ptr, tree decl)
if (!may_be_aliased (decl))
return false;
+ /* From here we require a SSA name pointer. Anything else aliases. */
+ if (TREE_CODE (ptr) != SSA_NAME
+ || !POINTER_TYPE_P (TREE_TYPE (ptr)))
+ return true;
+
/* If we do not have useful points-to information for this pointer
we cannot disambiguate anything else. */
pi = SSA_NAME_PTR_INFO (ptr);
--
2.43.0
