re PR tree-optimization/88739 (Big-endian union bug)

2019-01-28  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/88739
	* tree-cfg.c (verify_types_in_gimple_reference): Verify
	BIT_FIELD_REFs only are applied to mode-precision operands
	when they are integral.
	(verify_gimple_assign_ternary): Likewise for BIT_INSERT_EXPR.
	* tree-ssa-sccvn.c (vn_reference_lookup_3): Avoid generating
	BIT_FIELD_REFs of non-mode-precision integral operands.

From-SVN: r268332

gcc/ChangeLog

+2019-01-28  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/88739
+	* tree-cfg.c (verify_types_in_gimple_reference): Verify
+	BIT_FIELD_REFs only are applied to mode-precision operands
+	when they are integral.
+	(verify_gimple_assign_ternary): Likewise for BIT_INSERT_EXPR.
+	* tree-ssa-sccvn.c (vn_reference_lookup_3): Avoid generating
+	BIT_FIELD_REFs of non-mode-precision integral operands.
+
 2019-01-27  Jakub Jelinek  <jakub@redhat.com>
 
 	PR target/87214

gcc/tree-cfg.c

@@ -3118,6 +3118,12 @@ verify_types_in_gimple_reference (tree expr, bool require_lvalue)
 		     "match field size of BIT_FIELD_REF");
 	      return true;
 	    }
+	  if (INTEGRAL_TYPE_P (TREE_TYPE (op))
+	      && !type_has_mode_precision_p (TREE_TYPE (op)))
+	    {
+	      error ("BIT_FIELD_REF of non-mode-precision operand");
+	      return true;
+	    }
 	  if (!AGGREGATE_TYPE_P (TREE_TYPE (op))
 	      && maybe_gt (size + bitpos,
 			   tree_to_poly_uint64 (TYPE_SIZE (TREE_TYPE (op)))))
@@ -4319,6 +4325,12 @@ verify_gimple_assign_ternary (gassign *stmt)
 	  error ("invalid position or size in BIT_INSERT_EXPR");
 	  return true;
 	}
+      if (INTEGRAL_TYPE_P (rhs1_type)
+	  && !type_has_mode_precision_p (rhs1_type))
+	{
+	  error ("BIT_INSERT_EXPR into non-mode-precision operand");
+	  return true;
+	}
       if (INTEGRAL_TYPE_P (rhs1_type))
 	{
 	  unsigned HOST_WIDE_INT bitpos = tree_to_uhwi (rhs3);

gcc/tree-ssa-sccvn.c

@@ -2298,6 +2298,7 @@ vn_reference_lookup_3 (ao_ref *ref, tree vuse, void *vr_,
       base2 = get_ref_base_and_extent (gimple_assign_lhs (def_stmt),
 				       &offset2, &size2, &maxsize2,
 				       &reverse);
+      tree def_rhs = gimple_assign_rhs1 (def_stmt);
       if (!reverse
 	  && known_size_p (maxsize2)
 	  && known_eq (maxsize2, size2)
@@ -2309,11 +2310,13 @@ vn_reference_lookup_3 (ao_ref *ref, tree vuse, void *vr_,
 	     according to endianness.  */
 	  && (! INTEGRAL_TYPE_P (vr->type)
 	      || known_eq (ref->size, TYPE_PRECISION (vr->type)))
-	  && multiple_p (ref->size, BITS_PER_UNIT))
+	  && multiple_p (ref->size, BITS_PER_UNIT)
+	  && (! INTEGRAL_TYPE_P (TREE_TYPE (def_rhs))
+	      || type_has_mode_precision_p (TREE_TYPE (def_rhs))))
 	{
 	  gimple_match_op op (gimple_match_cond::UNCOND,
 			      BIT_FIELD_REF, vr->type,
-			      vn_valueize (gimple_assign_rhs1 (def_stmt)),
+			      vn_valueize (def_rhs),
 			      bitsize_int (ref->size),
 			      bitsize_int (offset - offset2));
 	  tree val = vn_nary_build_or_lookup (&op);