re PR tree-optimization/71893 (gfortran.dg ICEs in gcc/tree-ssa-pre.c; -fcode-hoisting?)

2016-07-18  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/71893
	* tree-ssa-pre.c (create_component_ref_by_pieces_1): Compensate
	for sizetype cast added by array_ref_element_size.
	* tree-ssa-sccvn.c (copy_reference_ops_from_ref): Likewise.

From-SVN: r238426

gcc/ChangeLog

+2016-07-18  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/71893
+	* tree-ssa-pre.c (create_component_ref_by_pieces_1): Compensate
+	for sizetype cast added by array_ref_element_size.
+	* tree-ssa-sccvn.c (copy_reference_ops_from_ref): Likewise.
+
 2016-07-16  John David Anglin  <danglin@gcc.gnu.org>
 
 	* config/pa/pa.c (hppa_profile_hook): Allocate stack space for

gcc/tree-ssa-pre.c

@@ -2576,6 +2576,9 @@ create_component_ref_by_pieces_1 (basic_block block, vn_reference_t ref,
 	      {
 		genop3 = size_binop (EXACT_DIV_EXPR, genop3,
 				     size_int (TYPE_ALIGN_UNIT (elmt_type)));
+		/* We may have a useless conversion added by
+		   array_ref_element_size via copy_reference_opts_from_ref.  */
+		STRIP_USELESS_TYPE_CONVERSION (genop3);
 		genop3 = find_or_generate_expression (block, genop3, stmts);
 		if (!genop3)
 		  return NULL_TREE;

gcc/tree-ssa-sccvn.c

@@ -810,6 +810,9 @@ copy_reference_ops_from_ref (tree ref, vec<vn_reference_op_s> *result)
 	  /* Always record lower bounds and element size.  */
 	  temp.op1 = array_ref_low_bound (ref);
 	  temp.op2 = array_ref_element_size (ref);
+	  /* array_ref_element_size forces the result to sizetype
+	     even if that is the same as bitsizetype.  */
+	  STRIP_USELESS_TYPE_CONVERSION (temp.op2);
 	  if (TREE_CODE (temp.op0) == INTEGER_CST
 	      && TREE_CODE (temp.op1) == INTEGER_CST
 	      && TREE_CODE (temp.op2) == INTEGER_CST)