public inbox for gcc-patches@gcc.gnu.org
 help / color / mirror / Atom feed
* [PATCH] Fix overflow in fold_const_aggregate_ref_1, PR90213
@ 2019-04-24 13:05 Richard Biener
  0 siblings, 0 replies; only message in thread
From: Richard Biener @ 2019-04-24 13:05 UTC (permalink / raw)
  To: gcc-patches


Bootstrap and regtest running on x86_64-unknown-linux-gnu.

Richard.

2019-04-24  Richard Biener  <rguenther@suse.de>

	PR middle-end/90213
	* gimple-fold.c (fold_const_aggregate_ref_1): Do multiplication
	by size and BITS_PER_UNIT on poly-wide-ints.

Index: gcc/gimple-fold.c
===================================================================
--- gcc/gimple-fold.c	(revision 270537)
+++ gcc/gimple-fold.c	(working copy)
@@ -6983,14 +6983,10 @@ fold_const_aggregate_ref_1 (tree t, tree
 		= wi::sext (wi::to_poly_offset (idx)
 			    - wi::to_poly_offset (low_bound),
 			    TYPE_PRECISION (TREE_TYPE (idx)));
-
+	      woffset *= tree_to_uhwi (unit_size);
+	      woffset *= BITS_PER_UNIT;
 	      if (woffset.to_shwi (&offset))
 		{
-		  /* TODO: This code seems wrong, multiply then check
-		     to see if it fits.  */
-		  offset *= tree_to_uhwi (unit_size);
-		  offset *= BITS_PER_UNIT;
-
 		  base = TREE_OPERAND (t, 0);
 		  ctor = get_base_constructor (base, &offset, valueize);
 		  /* Empty constructor.  Always fold to 0.  */

^ permalink raw reply	[flat|nested] only message in thread

only message in thread, other threads:[~2019-04-24 12:49 UTC | newest]

Thread overview: (only message) (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-04-24 13:05 [PATCH] Fix overflow in fold_const_aggregate_ref_1, PR90213 Richard Biener

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).