From: Jeff Law <law@redhat.com>
Date: Fri, 21 Jun 2019 16:36:00 +0000 (-0600)
Subject: re PR tree-optimization/90949 (null pointer check removed)
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=84338a14985c5f7b064a181180d221be16019978;p=gcc.git

re PR tree-optimization/90949 (null pointer check removed)

	PR tree-optimization/90949
	* tree-ssa-copy.c (fini_copy_prop): Use reset_flow_sensitive_info.
	* tree-ssanames.c (reset_flow_sensitive_info): Reset non-null state.

	* gcc.c-torture/execute/pr90949.c: New test.

From-SVN: r272555
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 73375ce9791..fa45d9d2185 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2019-06-21  Jeff Law  <law@redhat.com>
+
+	PR tree-optimization/90949
+	* tree-ssa-copy.c (fini_copy_prop): Use reset_flow_sensitive_info.
+	* tree-ssanames.c (reset_flow_sensitive_info): Reset non-null state.
+
 2019-06-21  Richard Biener  <rguenther@suse.de>
 
 	PR debug/90914
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 55ca5abef42..3f99b80dc3a 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2019-06-21  Jeff Law  <law@redhat.com>
+
+        PR tree-optimization/90949
+	* gcc.c-torture/execute/pr90949.c: New test.
+
 2019-06-21  Marek Polacek  <polacek@redhat.com>
 
 	PR c++/90953 - ICE with -Wmissing-format-attribute.
diff --git a/gcc/testsuite/gcc.c-torture/execute/pr90949.c b/gcc/testsuite/gcc.c-torture/execute/pr90949.c
new file mode 100644
index 00000000000..8c2ae3972d4
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/pr90949.c
@@ -0,0 +1,42 @@
+void __attribute__ ((noipa, noinline)) my_puts (const char *str) { }
+
+void __attribute__ ((noipa, noinline)) my_free (void *p) { }
+
+
+struct Node
+{
+  struct Node *child;
+};
+
+struct Node space[2] = { };
+
+struct Node * __attribute__ ((noipa, noinline)) my_malloc (int bytes)
+{
+  return &space[0];
+}
+
+void
+walk (struct Node *module, int cleanup)
+{
+  if (module == 0)
+    {
+      return;
+    }
+  if (!cleanup)
+    {
+      my_puts ("No cleanup");
+    }
+  walk (module->child, cleanup);
+  if (cleanup)
+    {
+      my_free (module);
+    }
+}
+
+int
+main ()
+{
+  struct Node *node = my_malloc (sizeof (struct Node));
+  node->child = 0;
+  walk (node, 1);
+}
diff --git a/gcc/tree-ssa-copy.c b/gcc/tree-ssa-copy.c
index 89532633e42..28ff8d3fbe2 100644
--- a/gcc/tree-ssa-copy.c
+++ b/gcc/tree-ssa-copy.c
@@ -545,13 +545,12 @@ fini_copy_prop (void)
 	      duplicate_ssa_name_ptr_info (copy_of[i].value,
 					   SSA_NAME_PTR_INFO (var));
 	      /* Points-to information is cfg insensitive,
-		 but alignment info might be cfg sensitive, if it
-		 e.g. is derived from VRP derived non-zero bits.
-		 So, do not copy alignment info if the two SSA_NAMEs
-		 aren't defined in the same basic block.  */
+		 but [E]VRP might record context sensitive alignment
+		 info, non-nullness, etc.  So reset context sensitive
+		 info if the two SSA_NAMEs aren't defined in the same
+		 basic block.  */
 	      if (var_bb != copy_of_bb)
-		mark_ptr_info_alignment_unknown
-				(SSA_NAME_PTR_INFO (copy_of[i].value));
+		reset_flow_sensitive_info (copy_of[i].value);
 	    }
 	  else if (!POINTER_TYPE_P (TREE_TYPE (var))
 		   && SSA_NAME_RANGE_INFO (var)
diff --git a/gcc/tree-ssanames.c b/gcc/tree-ssanames.c
index 5bac799e9a3..8b80bce8945 100644
--- a/gcc/tree-ssanames.c
+++ b/gcc/tree-ssanames.c
@@ -820,7 +820,12 @@ reset_flow_sensitive_info (tree name)
     {
       /* points-to info is not flow-sensitive.  */
       if (SSA_NAME_PTR_INFO (name))
-	mark_ptr_info_alignment_unknown (SSA_NAME_PTR_INFO (name));
+	{
+	  /* [E]VRP can derive context sensitive alignment info and
+	     non-nullness properties.  We must reset both.  */
+	  mark_ptr_info_alignment_unknown (SSA_NAME_PTR_INFO (name));
+	  SSA_NAME_PTR_INFO (name)->pt.null = 1;
+	}
     }
   else
     SSA_NAME_RANGE_INFO (name) = NULL;