re PR tree-optimization/87110 ([9 Regresssion] tree check fail in to_wide, at tree.h:5523)

	PR tree-optimization/87110
	* tree-ssa-dse.c (compute_trims): Handle non-constant
	TYPE_SIZE_UNIT.

	PR tree-optimization/87110
	* gcc.c-torture/compile/pr87110.c: New test.

From-SVN: r263906

gcc/ChangeLog

+2018-08-27  Jeff Law  <law@redhat.com>
+
+	PR tree-optimization/87110
+	* tree-ssa-dse.c (compute_trims): Handle non-constant
+	TYPE_SIZE_UNIT.
+
 2018-08-27  Martin Sebor  <msebor@redhat.com>
 
 	PR tree-optimization/86914

gcc/testsuite/ChangeLog

+2018-08-27  Jeff Law  <law@redhat.com>
+
+	PR tree-optimization/87110
+	* gcc.c-torture/compile/pr87110.c: New test.
+
 2018-08-27  Martin Sebor  <msebor@redhat.com>
 
 	PR tree-optimization/86914

gcc/testsuite/gcc.c-torture/compile/pr87110.c

+enum a { b, c };
+struct d {
+  _Bool e;
+  enum a f
+};
+g, h;
+i() {
+  struct d j[h];
+  j[0] = (struct d){.f = c};
+  for (; g;)
+    (struct d){};
+}
+

gcc/tree-ssa-dse.c

@@ -250,9 +250,13 @@ compute_trims (ao_ref *ref, sbitmap live, int *trim_head, int *trim_tail,
       *trim_tail = last_orig - last_live;
 
       /* But don't trim away out of bounds accesses, as this defeats
-	 proper warnings.  */
+	 proper warnings.
+
+	 We could have a type with no TYPE_SIZE_UNIT or we could have a VLA
+	 where TYPE_SIZE_UNIT is not a constant.  */
       if (*trim_tail
 	  && TYPE_SIZE_UNIT (TREE_TYPE (ref->base))
+	  && TREE_CODE (TYPE_SIZE_UNIT (TREE_TYPE (ref->base))) == INTEGER_CST
 	  && compare_tree_int (TYPE_SIZE_UNIT (TREE_TYPE (ref->base)),
 			       last_orig) <= 0)
 	*trim_tail = 0;