gimple-match-head.c (do_valueize): Return OP if valueize returns NULL_TREE.

2017-07-26  Richard Biener  <rguenther@suse.de>

	* gimple-match-head.c (do_valueize): Return OP if valueize
	returns NULL_TREE.
	(get_def): New helper to get at the def stmt of a SSA name
	if valueize allows.
	* genmatch.c (dt_node::gen_kids_1): Use get_def instead of
	do_valueize to get at the def stmt.
	(dt_operand::gen_gimple_expr): Simplify do_valueize calls.

	* gcc/testsuite/gcc.dg/pr70920-2.c: Adjust for transform already
	happening in ccp1.
	* gcc/testsuite/gcc.dg/pr70920-4.c: Likewise.

From-SVN: r250565

1 files changed, 16 insertions, 1 deletions

diff --git a/gcc/gimple-match-head.c b/gcc/gimple-match-head.c
index 5f6aa273..8ad1f8c 100644
--- a/gcc/gimple-match-head.c
+++ b/gcc/gimple-match-head.c
@@ -779,10 +779,25 @@ inline tree
 do_valueize (tree (*valueize)(tree), tree op)
 {
   if (valueize && TREE_CODE (op) == SSA_NAME)
-    return valueize (op);
+    {
+      tree tem = valueize (op);
+      if (tem)
+	return tem;
+    }
   return op;
 }
 
+/* Helper for the autogenerated code, get at the definition of NAME when
+   VALUEIZE allows that.  */
+
+inline gimple *
+get_def (tree (*valueize)(tree), tree name)
+{
+  if (valueize && ! valueize (name))
+    return NULL;
+  return SSA_NAME_DEF_STMT (name);
+}
+
 /* Routine to determine if the types T1 and T2 are effectively
    the same for GIMPLE.  If T1 or T2 is not a type, the test
    applies to their TREE_TYPE.  */