re PR debug/83621 (ICE: in simplify_subreg, at simplify-rtx.c:6293 with -O -g)

	PR debug/83621
	* cfgexpand.c (expand_debug_expr): Return NULL if mode is
	BLKmode for ternary, binary or unary expressions.

	* gcc.dg/pr83621.c: New test.

From-SVN: r256190

gcc/ChangeLog

 2018-01-03  Jakub Jelinek  <jakub@redhat.com>
 
+	PR debug/83621
+	* cfgexpand.c (expand_debug_expr): Return NULL if mode is
+	BLKmode for ternary, binary or unary expressions.
+
 	PR debug/83645
 	* var-tracking.c (delete_vta_debug_insn): New inline function.
 	(delete_vta_debug_insns): Add USE_CFG argument, if true, walk just

gcc/cfgexpand.c

@@ -4208,6 +4208,8 @@ expand_debug_expr (tree exp)
 
     binary:
     case tcc_binary:
+      if (mode == BLKmode)
+	return NULL_RTX;
       op1 = expand_debug_expr (TREE_OPERAND (exp, 1));
       if (!op1)
 	return NULL_RTX;
@@ -4232,6 +4234,8 @@ expand_debug_expr (tree exp)
 
     unary:
     case tcc_unary:
+      if (mode == BLKmode)
+	return NULL_RTX;
       inner_mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0)));
       op0 = expand_debug_expr (TREE_OPERAND (exp, 0));
       if (!op0)

gcc/testsuite/ChangeLog

 2018-01-03  Jakub Jelinek  <jakub@redhat.com>
 
+	PR debug/83621
+	* gcc.dg/pr83621.c: New test.
+
 	PR debug/83645
 	* gcc.dg/pr83645.c: New test.
 

gcc/testsuite/gcc.dg/pr83621.c

+/* PR debug/83621 */
+/* { dg-do compile } */
+/* { dg-options "-O -g" } */
+
+typedef int __attribute__ ((__vector_size__ (64))) V;
+V v;
+
+void
+foo ()
+{
+  V u = v >> 1;
+}