re PR tree-optimization/68502 ([i686] spec2000/179.art runfails after r222914)

2015-11-25  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/68502
	* tree-vect-data-refs.c (vect_analyze_group_access_1): Restore
	check that the step is a multiple of the type size.

	* gcc.dg/vect/pr68502-1.c: New testcase.
	* gcc.dg/vect/pr68502-2.c: Likewise.

From-SVN: r230854

gcc/ChangeLog

+2015-11-25  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/68502
+	* tree-vect-data-refs.c (vect_analyze_group_access_1): Restore
+	check that the step is a multiple of the type size.
+
 2015-11-24  Michael Collison  <michael.collison@linaro.org>
 
 	* config/aarch64/aarch64-simd.md (widen_ssum, widen_usum)

gcc/testsuite/ChangeLog

+2015-11-25  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/68502
+	* gcc.dg/vect/pr68502-1.c: New testcase.
+	* gcc.dg/vect/pr68502-2.c: Likewise.
+
 2015-11-24  Michael Collison  <michael.collison@linaro.org>
 
 	* gcc.target/aarch64/saddw-1.c: New test.

gcc/testsuite/gcc.dg/vect/pr68502-1.c

+#include <stdlib.h>
+#include "tree-vect.h"
+
+typedef struct {
+    double *I;
+    double W;
+    double X;
+    double V;
+    double U;
+    double P;
+    double Q;
+    double R;
+} f1_neuron;
+
+f1_neuron *f1_layer;
+
+int numf1s = 1000;
+
+void __attribute__((noinline,noclone))
+reset_nodes() 
+{
+  int i;
+
+  for (i=0;i<numf1s;i++)
+    {
+      f1_layer[i].W = 0.0;
+      f1_layer[i].X = 0.0;
+      f1_layer[i].V = 0.0;
+      f1_layer[i].U = 0.0;
+      f1_layer[i].P = 0.0;
+      f1_layer[i].Q = 0.0;
+      f1_layer[i].R = 0.0;
+    }
+}
+
+int main ()
+{
+  int i;
+  check_vect ();
+  f1_layer = (f1_neuron *)malloc (numf1s * sizeof (f1_neuron));
+  for (i = 0; i < numf1s; i++)
+    f1_layer[i].I = (double *)-1;
+  reset_nodes ();
+  for (i = 0; i < numf1s; i++)
+    if (f1_layer[i].I != (double *)-1)
+      abort ();
+  return 0; 
+}

gcc/testsuite/gcc.dg/vect/pr68502-2.c

+#include <stdlib.h>
+#include "tree-vect.h"
+
+typedef struct {
+    short I;
+    int W;
+    int X;
+    int V;
+    int U;
+    int P;
+    int Q;
+    int R;
+} __attribute__((packed)) f1_neuron;
+
+f1_neuron *f1_layer;
+
+int numf1s = 1000;
+
+void __attribute__((noinline,noclone))
+reset_nodes() 
+{
+  int i;
+
+  for (i=0;i<numf1s;i++)
+    {
+      f1_layer[i].W = 0;
+      f1_layer[i].X = 0;
+      f1_layer[i].V = 0;
+      f1_layer[i].U = 0;
+      f1_layer[i].P = 0;
+      f1_layer[i].Q = 0;
+      f1_layer[i].R = 0;
+    }
+}
+
+int main ()
+{
+  int i;
+  check_vect ();
+  f1_layer = (f1_neuron *)malloc (numf1s * sizeof (f1_neuron));
+  for (i = 0; i < numf1s; i++)
+    f1_layer[i].I = -1;
+  reset_nodes ();
+  for (i = 0; i < numf1s; i++)
+    if (f1_layer[i].I != -1)
+      abort ();
+  return 0; 
+}

gcc/tree-vect-data-refs.c

@@ -2176,6 +2176,27 @@ vect_analyze_group_access_1 (struct data_reference *dr)
   if (tree_fits_shwi_p (step))
     {
       dr_step = tree_to_shwi (step);
+      /* Check that STEP is a multiple of type size.  Otherwise there is
+         a non-element-sized gap at the end of the group which we
+	 cannot represent in GROUP_GAP or GROUP_SIZE.
+	 ???  As we can handle non-constant step fine here we should
+	 simply remove uses of GROUP_GAP between the last and first
+	 element and instead rely on DR_STEP.  GROUP_SIZE then would
+	 simply not include that gap.  */
+      if ((dr_step % type_size) != 0)
+	{
+	  if (dump_enabled_p ())
+	    {
+	      dump_printf_loc (MSG_NOTE, vect_location,
+	                       "Step ");
+	      dump_generic_expr (MSG_NOTE, TDF_SLIM, step);
+	      dump_printf (MSG_NOTE,
+			   " is not a multiple of the element size for ");
+	      dump_generic_expr (MSG_NOTE, TDF_SLIM, DR_REF (dr));
+	      dump_printf (MSG_NOTE, "\n");
+	    }
+	  return false;
+	}
       groupsize = absu_hwi (dr_step) / type_size;
     }
   else