Set nonnull attribute to ptr_info_def based on VRP

[thirdparty/gcc.git] / gcc / tree-ssanames.c

diff --git a/gcc/tree-ssanames.c b/gcc/tree-ssanames.c
index 64ab13a20487e95541dcd8d39b4dea4bdd386c23..913d142f0462e1647401bdefa21c2527b153ed5b 100644 (file)
--- a/gcc/tree-ssanames.c
+++ b/gcc/tree-ssanames.c
@@ -374,6 +374,35 @@ get_range_info (const_tree name, wide_int *min, wide_int *max)
   return SSA_NAME_RANGE_TYPE (name);
 }
 
+/* Set nonnull attribute to pointer NAME.  */
+
+void
+set_ptr_nonnull (tree name)
+{
+  gcc_assert (POINTER_TYPE_P (TREE_TYPE (name)));
+  struct ptr_info_def *pi = get_ptr_info (name);
+  pi->pt.null = 0;
+}
+
+/* Return nonnull attribute of pointer NAME.  */
+bool
+get_ptr_nonnull (const_tree name)
+{
+  gcc_assert (POINTER_TYPE_P (TREE_TYPE (name)));
+  struct ptr_info_def *pi = SSA_NAME_PTR_INFO (name);
+  if (pi == NULL)
+    return false;
+  /* TODO Now pt->null is conservatively set to true in PTA
+     analysis. vrp is the only pass (including ipa-vrp)
+     that clears pt.null via set_ptr_nonull when it knows
+     for sure. PTA will preserves the pt.null value set by VRP.
+
+     When PTA analysis is improved, pt.anything, pt.nonlocal
+     and pt.escaped may also has to be considered before
+     deciding that pointer cannot point to NULL.  */
+  return !pi->pt.null;
+}
+
 /* Change non-zero bits bitmask of NAME.  */
 
 void