re PR tree-optimization/56826 (Run-fail after r197189.)

2013-04-04  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/56826
	* tree-vect-slp.c (vect_build_slp_tree): Compute ncopies
	more accurately.

	* gcc.dg/vect/pr56826.c: New testcase.
	* gcc.dg/vect/O3-pr36098.c: Adjust.

From-SVN: r197486

gcc/ChangeLog

 2013-04-04  Richard Biener  <rguenther@suse.de>
 
+	PR tree-optimization/56826
+	* tree-vect-slp.c (vect_build_slp_tree): Compute ncopies
+	more accurately.
+
+2013-04-04  Richard Biener  <rguenther@suse.de>
+
 	PR tree-optimization/56213
 	* tree-vect-data-refs.c (vect_check_strided_load): Remove.
 	(vect_analyze_data_refs): Allow all non-nested loads as

gcc/testsuite/ChangeLog

+2013-04-04  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/56826
+	* gcc.dg/vect/pr56826.c: New testcase.
+	* gcc.dg/vect/O3-pr36098.c: Adjust.
+
 2013-04-04  Tejas Belagod  <tejas.belagod@arm.com>
 
 	* gcc.target/aarch64/inc/asm-adder-clobber-lr.c: Remove duplication.

gcc/testsuite/gcc.dg/vect/O3-pr36098.c

@@ -17,5 +17,5 @@ void foo (int ncons, t_sortblock *sb, int *iatom)
      iatom[m]=sb[i].iatom[m];
 }
 
-/* { dg-final { scan-tree-dump-times "vectorizing stmts using SLP" 1 "vect" } } */
+/* { dg-final { scan-tree-dump-times "vectorizing stmts using SLP" 0 "vect" } } */
 /* { dg-final { cleanup-tree-dump "vect" } } */

gcc/testsuite/gcc.dg/vect/pr56826.c

+extern void abort (void);
+
+typedef struct {
+    int a[3];
+    int num;
+} t1;
+t1 B[100];
+int A[300];
+
+void __attribute__((noinline,noclone))
+bar (int *A, t1 *B, int n)
+{
+  int i;
+  int *a = A;
+  for (i=0; i<n; i++, a+=3)
+    {
+      a[0] = B[i].a[0];
+      a[1] = B[i].a[1];
+      a[2] = B[i].a[2];
+    }
+}
+
+int main()
+{
+  int i;
+  for (i=0; i<100; i++) 
+    {
+      B[i].num = i;
+      B[i].a[0] = i * 3;
+      B[i].a[1] = i * 3 + 1;
+      B[i].a[2] = i * 3 + 2;
+      __asm__ volatile ("");
+    }
+  bar (&A[0], &B[0], 100);
+  for (i=0; i<300; i++)
+    if (A[i] != i)
+      abort ();
+  return 0;
+} 
+
+/* { dg-final { cleanup-tree-dump "vect" } } */

gcc/tree-vect-slp.c

@@ -470,7 +470,6 @@ vect_build_slp_tree (loop_vec_info loop_vinfo, bb_vec_info bb_vinfo,
   tree lhs;
   bool stop_recursion = false, need_same_oprnds = false;
   tree vectype, scalar_type, first_op1 = NULL_TREE;
-  unsigned int ncopies;
   optab optab;
   int icode;
   enum machine_mode optab_op2_mode;
@@ -577,8 +576,6 @@ vect_build_slp_tree (loop_vec_info loop_vinfo, bb_vec_info bb_vinfo,
             vectorization_factor = *max_nunits;
         }
 
-      ncopies = vectorization_factor / TYPE_VECTOR_SUBPARTS (vectype);
-
       if (is_gimple_call (stmt))
 	{
 	  rhs_code = CALL_EXPR;
@@ -741,12 +738,15 @@ vect_build_slp_tree (loop_vec_info loop_vinfo, bb_vec_info bb_vinfo,
 	  else
 	    {
 	      /* Load.  */
+	      unsigned unrolling_factor
+		= least_common_multiple
+		    (*max_nunits, group_size) / group_size;
               /* FORNOW: Check that there is no gap between the loads
 		 and no gap between the groups when we need to load
 		 multiple groups at once.
 		 ???  We should enhance this to only disallow gaps
 		 inside vectors.  */
-              if ((ncopies > 1
+              if ((unrolling_factor > 1
 		   && GROUP_FIRST_ELEMENT (vinfo_for_stmt (stmt)) == stmt
 		   && GROUP_GAP (vinfo_for_stmt (stmt)) != 0)
 		  || (GROUP_FIRST_ELEMENT (vinfo_for_stmt (stmt)) != stmt
@@ -767,6 +767,8 @@ vect_build_slp_tree (loop_vec_info loop_vinfo, bb_vec_info bb_vinfo,
 
               /* Check that the size of interleaved loads group is not
                  greater than the SLP group size.  */
+	      unsigned ncopies
+		= vectorization_factor / TYPE_VECTOR_SUBPARTS (vectype);
               if (loop_vinfo
 		  && GROUP_FIRST_ELEMENT (vinfo_for_stmt (stmt)) == stmt
                   && ((GROUP_SIZE (vinfo_for_stmt (stmt))