re PR middle-end/89765 (Multiple problems with vec-insert implementation on PowerPC)

	PR middle-end/89765
	* gimplify.c (gimplify_expr): Avoid turning a lvalue
	VIEW_CONVERT_EXPR into one operating on an rvalue.

From-SVN: r270579

gcc/ChangeLog

+2019-04-25  Richard Biener  <rguenther@suse.de>
+
+	PR middle-end/89765
+	* gimplify.c (gimplify_expr): Avoid turning a lvalue
+	VIEW_CONVERT_EXPR into one operating on an rvalue.
+
 2019-04-25  H.J. Lu  <hongjiu.lu@intel.com>
 
 	PR target/89929

gcc/gimplify.c

@@ -12397,7 +12397,8 @@ gimplify_expr (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p,
 	  break;
 
 	case VIEW_CONVERT_EXPR:
-	  if (is_gimple_reg_type (TREE_TYPE (*expr_p))
+	  if ((fallback & fb_rvalue)
+	      && is_gimple_reg_type (TREE_TYPE (*expr_p))
 	      && is_gimple_reg_type (TREE_TYPE (TREE_OPERAND (*expr_p, 0))))
 	    {
 	      ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p,