[Bug c/39500] autopar fails to parallel

[nemokingdom at gmail dot com]

------- Comment #4 from nemokingdom at gmail dot com  2009-03-19 02:46 -------
(In reply to comment #3)
> I will take care of this one.
> 
I add test case for this situation.

Index: testsuite/gcc.dg/autopar/pr39500-1.c
===================================================================
--- testsuite/gcc.dg/autopar/pr39500-1.c        (revision 0)
+++ testsuite/gcc.dg/autopar/pr39500-1.c        (revision 0)
@@ -0,0 +1,29 @@
+/* pr39500: autopar fails to parallel */
+/* origin: nemokingdom@gmail.com(LiFeng)*/
+/* { dg-do compile } */
+/* { dg-options "-O2 -ftree-parallelize-loops=4 -fdump-tree-parloops-details
-fdump-tree-final_cleanup" } */
+
+void abort (void);
+
+int main(void)
+{
+  int i;
+  int x[100];
+
+  for (i = 0; i < 100; i++)
+      x[i] = x[i+100];
+
+  for (i = 0; i < 100; i++)
+    {
+      if (x[i] != x[i+100])
+       abort ();
+    }
+
+  return 0;
+}
+
+/* Check that the first loop in parloop got parallelized.  */
+
+/* { dg-final { scan-tree-dump-times "SUCCESS: may be parallelized" 1
"parloops" } } */
+/* { dg-final { cleanup-tree-dump "parloops" } } */
+/* { dg-final { cleanup-tree-dump "final_cleanup" } } */
Index: testsuite/gcc.dg/autopar/pr39500-2.c
===================================================================
--- testsuite/gcc.dg/autopar/pr39500-2.c        (revision 0)
+++ testsuite/gcc.dg/autopar/pr39500-2.c        (revision 0)
@@ -0,0 +1,21 @@
+/* pr39500: autopar fails to parallel */
+/* origin: nemokingdom@gmail.com(LiFeng)*/
+/* { dg-do compile } */
+/* { dg-options "-O2 -ftree-parallelize-loops=4 -fdump-tree-parloops-details
-fdump-tree-final_cleanup" } */
+
+int main(void)
+{
+  int i;
+  int x[100];
+
+  for (i = 0; i < 101; i++)
+      x[i] = x[i+100];
+
+  return 0;
+}
+
+/* Check that the first loop in parloop got parallelized.  */
+
+/* { dg-final { scan-tree-dump-times "SUCCESS: may be parallelized" 0
"parloops" } } */
+/* { dg-final { cleanup-tree-dump "parloops" } } */
+/* { dg-final { cleanup-tree-dump "final_cleanup" } } */
Index: tree-data-ref.c
===================================================================
--- tree-data-ref.c     (revision 144648)
+++ tree-data-ref.c     (working copy)
@@ -2302,7 +2302,7 @@

                  /* If the overlap occurs outside of the bounds of the
                     loop, there is no dependence.  */
-                 if (x1 > niter || y1 > niter)
+                 if (x1 >= niter || y1 >= niter)
                    {
                      *overlaps_a = conflict_fn_no_dependence ();
                      *overlaps_b = conflict_fn_no_dependence ();


-- 

nemokingdom at gmail dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|middle-end                  |c


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39500