re PR ipa/88936 (-fipa-pta breaks bash (incorrect optimisation of recursive static function))

2019-04-15  Richard Biener  <rguenther@suse.de>

	PR ipa/88936
	* tree.h (auto_var_p): Declare.
	* tree.c (auto_var_p): New function, split out from ...
	(auto_var_in_fn_p): ... here.
	* tree-ssa-structalias.c (struct variable_info): Add shadow_var_uid
	member.
	(new_var_info): Initialize it.
	(set_uids_in_ptset): Also set the shadow variable uid if required.
	(ipa_pta_execute): Postprocess points-to solutions assigning
	shadow variable uids for locals that may reach their containing
	function recursively.
	* tree-ssa-ccp.c (fold_builtin_alloca_with_align): Do not
	assert but instead check whether the points-to solution is
	a singleton.

	* gcc.dg/torture/pr88936-1.c: New testcase.
	* gcc.dg/torture/pr88936-2.c: Likewise.
	* gcc.dg/torture/pr88936-3.c: Likewise.

From-SVN: r270366

1 files changed, 13 insertions, 5 deletions

diff --git a/gcc/tree.c b/gcc/tree.c
index 65f8cd3..a483cc1 100644
--- a/gcc/tree.c
+++ b/gcc/tree.c
@@ -9268,17 +9268,25 @@ get_type_static_bounds (const_tree type, mpz_t min, mpz_t max)
     }
 }
 
+/* Return true if VAR is an automatic variable.  */
+
+bool
+auto_var_p (const_tree var)
+{
+  return ((((VAR_P (var) && ! DECL_EXTERNAL (var))
+	    || TREE_CODE (var) == PARM_DECL)
+	   && ! TREE_STATIC (var))
+	  || TREE_CODE (var) == RESULT_DECL);
+}
+
 /* Return true if VAR is an automatic variable defined in function FN.  */
 
 bool
 auto_var_in_fn_p (const_tree var, const_tree fn)
 {
   return (DECL_P (var) && DECL_CONTEXT (var) == fn
-	  && ((((VAR_P (var) && ! DECL_EXTERNAL (var))
-		|| TREE_CODE (var) == PARM_DECL)
-	       && ! TREE_STATIC (var))
-	      || TREE_CODE (var) == LABEL_DECL
-	      || TREE_CODE (var) == RESULT_DECL));
+	  && (auto_var_p (var)
+	      || TREE_CODE (var) == LABEL_DECL));
 }
 
 /* Subprogram of following function.  Called by walk_tree.