Makefile.in (tree-data-ref.o): Add tree-affine.h dependency.

2011-08-23  Richard Guenther  <rguenther@suse.de>

	* Makefile.in (tree-data-ref.o): Add tree-affine.h dependency.
	* tree-affine.h (aff_comb_cannot_overlap_p): Declare.
	* tree-affine.c (aff_comb_cannot_overlap_p): New function, moved
	from ...
	* tree-ssa-loop-im.c (cannot_overlap_p): ... here.
	(mem_refs_may_alias_p): Adjust.
	* tree-data-ref.h (dr_may_alias_p): Adjust.
	* tree-data-ref.c: Include tree-affine.h.
	(dr_analyze_indices): Do nothing for the non-loop case.
	(dr_may_alias_p): Distinguish loop and non-loop case.  Disambiguate
	more cases in the non-loop case.
	* graphite-sese-to-poly.c (write_alias_graph_to_ascii_dimacs): Adjust
	calls to dr_may_alias_p.
	(write_alias_graph_to_ascii_ecc): Likewise.
	(write_alias_graph_to_ascii_dot): Likewise.
	(build_alias_set_optimal_p): Likewise.

From-SVN: r177986

1 files changed, 27 insertions, 0 deletions

diff --git a/gcc/tree-affine.c b/gcc/tree-affine.c
index 06b7f26..69cce2e 100644
--- a/gcc/tree-affine.c
+++ b/gcc/tree-affine.c
@@ -887,3 +887,30 @@ get_inner_reference_aff (tree ref, aff_tree *addr, double_int *size)
   *size = shwi_to_double_int ((bitsize + BITS_PER_UNIT - 1) / BITS_PER_UNIT);
 }
 
+/* Returns true if a region of size SIZE1 at position 0 and a region of
+   size SIZE2 at position DIFF cannot overlap.  */
+
+bool
+aff_comb_cannot_overlap_p (aff_tree *diff, double_int size1, double_int size2)
+{
+  double_int d, bound;
+
+  /* Unless the difference is a constant, we fail.  */
+  if (diff->n != 0)
+    return false;
+
+  d = diff->offset;
+  if (double_int_negative_p (d))
+    {
+      /* The second object is before the first one, we succeed if the last
+	 element of the second object is before the start of the first one.  */
+      bound = double_int_add (d, double_int_add (size2, double_int_minus_one));
+      return double_int_negative_p (bound);
+    }
+  else
+    {
+      /* We succeed if the second object starts after the first one ends.  */
+      return double_int_scmp (size1, d) <= 0;
+    }
+}
+