re PR tree-optimization/58626 (possible array wrong code bug)

2013-10-25  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/58626
	* tree-loop-distribution.c (enum rdg_dep_type): Remove
	anti_dd, output_dd and input_dd.
	(struct rdg_edge): Remove level and relation members.
	(RDGE_LEVEL, RDGE_RELATION): Remove.
	(dot_rdg_1): Adjust.
	(create_rdg_edge_for_ddr): Remove.
	(create_rdg_edges_for_scalar): Adjust.
	(create_edge_for_control_dependence): Likewise.
	(create_rdg_edges): Split into ...
	(create_rdg_flow_edges): ... this
	(create_rdg_cd_edges): ... and this.
	(free_rdg): Adjust.
	(build_rdg): Likewise, do not compute data dependences or
	add edges for them.
	(pg_add_dependence_edges): New function.
	(pgcmp): Likewise.
	(distribute_loop): First apply all non-dependence based
	partition mergings.  Then compute dependences between partitions
	and merge and order partitions according to them.

	* gcc.dg/torture/pr58626.c: New testcase.

From-SVN: r204062

gcc/ChangeLog

+2013-10-25  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/58626
+	* tree-loop-distribution.c (enum rdg_dep_type): Remove
+	anti_dd, output_dd and input_dd.
+	(struct rdg_edge): Remove level and relation members.
+	(RDGE_LEVEL, RDGE_RELATION): Remove.
+	(dot_rdg_1): Adjust.
+	(create_rdg_edge_for_ddr): Remove.
+	(create_rdg_edges_for_scalar): Adjust.
+	(create_edge_for_control_dependence): Likewise.
+	(create_rdg_edges): Split into ...
+	(create_rdg_flow_edges): ... this
+	(create_rdg_cd_edges): ... and this.
+	(free_rdg): Adjust.
+	(build_rdg): Likewise, do not compute data dependences or
+	add edges for them.
+	(pg_add_dependence_edges): New function.
+	(pgcmp): Likewise.
+	(distribute_loop): First apply all non-dependence based
+	partition mergings.  Then compute dependences between partitions
+	and merge and order partitions according to them.
+
 2013-10-25  Eric Botcazou  <ebotcazou@adacore.com>
 
 	PR rtl-optimization/58831

gcc/testsuite/ChangeLog

+2013-10-25  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/58626
+	* gcc.dg/torture/pr58626.c: New testcase.
+
 2013-10-25  Paolo Carlini  <paolo.carlini@oracle.com>
 
 	PR c++/54812

gcc/testsuite/gcc.dg/torture/pr58626.c

+/* { dg-do run } */
+
+extern void abort (void);
+
+int a[8][6] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 };
+int b;
+
+int main(void)
+{
+  for (b = 0; b <= 1; b++) {
+      a[1][3] = 0;
+      int c;
+      for (c = 0; c <= 1; c++) {
+	  a[c + 1][b] = a[c + 2][b];
+      }
+  }
+  if (a[1][1] != 1)
+    abort ();
+  return 0;
+}