re PR tree-optimization/55857 (ICE: verify_ssa failed)

2013-01-03  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/55857
	* tree-vect-stmts.c (vectorizable_load): Do not setup
	re-alignment for invariant loads.

	* gcc.dg/vect/pr55857-1.c: New testcase.
	* gcc.dg/vect/pr55857-2.c: Likewise.

From-SVN: r194850

gcc/ChangeLog

 2013-01-03  Richard Biener  <rguenther@suse.de>
 
+	PR tree-optimization/55857
+	* tree-vect-stmts.c (vectorizable_load): Do not setup
+	re-alignment for invariant loads.
+
+2013-01-03  Richard Biener  <rguenther@suse.de>
+
 	PR lto/55848
 	* lto-symtab.c (lto_symtab_merge_decls_1): As last resort, always
 	prefer a built-in decl.

gcc/testsuite/ChangeLog

+2013-01-03  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/55857
+	* gcc.dg/vect/pr55857-1.c: New testcase.
+	* gcc.dg/vect/pr55857-2.c: Likewise.
+
 2013-01-03  Jakub Jelinek  <jakub@redhat.com>
 
 	PR rtl-optimization/55838

gcc/testsuite/gcc.dg/vect/pr55857-1.c

+/* { dg-do compile } */
+
+void 
+foo (int *data, unsigned len, const int qlp_coeff[], int lp, int residual[])
+{
+  int i;
+  int sum;
+  for(i = 0; i < (int)len; i++)
+    {     
+      sum = 0;   
+      sum += qlp_coeff[1] * data[i-2];   
+      sum += qlp_coeff[0] * data[i-1];   
+      residual[i] = data[i] - (sum >> lp);
+    }    
+}
+
+/* { dg-final { cleanup-tree-dump "vect" } } */

gcc/testsuite/gcc.dg/vect/pr55857-2.c

+/* { dg-do compile } */
+
+void foo (int *data, unsigned len, const int qlp_coeff[],
+	  unsigned order, int lp, int residual[])
+{
+  int i;
+  int sum;
+  if(order == 2)
+    for(i = 0; i < (int)len; i++)
+      {
+	sum = 0;
+	sum += qlp_coeff[1] * data[i-2]; 
+	sum += qlp_coeff[0] * data[i-1];
+	residual[i] = data[i] - (sum >> lp);
+      }
+  else
+    for(i = 0; i < (int)len; i++)  
+      residual[i] = data[i] - ((qlp_coeff[0] * data[i-1]) >> lp);
+}
+
+/* { dg-final { cleanup-tree-dump "vect" } } */

gcc/tree-vect-stmts.c

@@ -4927,7 +4927,8 @@ vectorizable_load (gimple stmt, gimple_stmt_iterator *gsi, gimple *vec_stmt,
 
   if ((alignment_support_scheme == dr_explicit_realign_optimized
        || alignment_support_scheme == dr_explicit_realign)
-      && !compute_in_loop)
+      && !compute_in_loop
+      && !integer_zerop (DR_STEP (dr)))
     {
       msq = vect_setup_realignment (first_stmt, gsi, &realignment_token,
 				    alignment_support_scheme, NULL_TREE,