re PR tree-optimization/49518 (ICE in vect_enhance_data_refs_alignment, at tree-vect-data-refs.c:1555)

2011-07-05  Richard Guenther  <rguenther@suse.de>

	PR tree-optimization/49518
	PR tree-optimization/49628
	* tree-vect-data-refs.c (vect_enhance_data_refs_alignment): Skip
	irrelevant and invariant data-references.
	(vect_analyze_data_ref_access): For invariant loads clear the
	group association.

	* g++.dg/torture/pr49628.C: New testcase.
	* gcc.dg/torture/pr49518.c: Likewise.

From-SVN: r175847

5 files changed, 83 insertions, 1 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 2c592b2..154c7ca 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,12 @@
+2011-07-05  Richard Guenther  <rguenther@suse.de>
+
+	PR tree-optimization/49518
+	PR tree-optimization/49628
+	* tree-vect-data-refs.c (vect_enhance_data_refs_alignment): Skip
+	irrelevant and invariant data-references.
+	(vect_analyze_data_ref_access): For invariant loads clear the
+	group association.
+
 2011-07-04  Jakub Jelinek  <jakub@redhat.com>
 
 	PR rtl-optimization/49619
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 7a4b5bb..5839b72 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,10 @@
+2011-07-05  Richard Guenther  <rguenther@suse.de>
+
+	PR tree-optimization/49518
+	PR tree-optimization/49628
+	* g++.dg/torture/pr49628.C: New testcase.
+	* gcc.dg/torture/pr49518.c: Likewise.
+
 2011-07-05  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>
 
 	* ada/acats/run_acats (which): Extract last field from type -p,
diff --git a/gcc/testsuite/g++.dg/torture/pr49628.C b/gcc/testsuite/g++.dg/torture/pr49628.C
new file mode 100644
index 0000000..4bc6543
--- /dev/null
+++ b/gcc/testsuite/g++.dg/torture/pr49628.C
@@ -0,0 +1,37 @@
+/* { dg-do compile } */
+
+#include <vector>
+
+template <int rank, int dim> class Tensor;
+template <int dim> class Tensor<1,dim> {
+public:
+    explicit Tensor (const bool initialize = true);
+    Tensor (const Tensor<1,dim> &);
+    Tensor<1,dim> & operator = (const Tensor<1,dim> &);
+    double values[(dim!=0) ? (dim) : 1];
+};
+template <int dim>
+inline Tensor<1,dim> & Tensor<1,dim>::operator = (const Tensor<1,dim> &p)
+{
+  for (unsigned int i=0; i<dim; ++i)
+    values[i] = p.values[i];
+};
+template <int dim> class Quadrature {
+public:
+    const unsigned int n_quadrature_points;
+};
+class MappingQ1
+{
+  class InternalData  {
+  public:
+      std::vector<Tensor<1,3> > shape_derivatives;
+      unsigned int n_shape_functions;
+  };
+  void compute_data (const Quadrature<3> &quadrature, InternalData &data)
+      const;
+};
+void MappingQ1::compute_data (const Quadrature<3> &q, InternalData &data) const
+{
+  const unsigned int n_q_points = q.n_quadrature_points;
+  data.shape_derivatives.resize(data.n_shape_functions * n_q_points);
+}
diff --git a/gcc/testsuite/gcc.dg/torture/pr49518.c b/gcc/testsuite/gcc.dg/torture/pr49518.c
new file mode 100644
index 0000000..84a10fb
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr49518.c
@@ -0,0 +1,19 @@
+/* { dg-do compile } */
+
+int a, b;
+struct S { unsigned int s, t, u; } c, d = { 0, 1, 0 };
+
+void
+test (unsigned char z)
+{
+  char e[] = {0, 0, 0, 0, 1};
+  for (c.s = 1; c.s; c.s++)
+    {
+      b = e[c.s];
+      if (a)
+	break;
+      b = z >= c.u;
+      if (d.t)
+	break;
+    }
+}
diff --git a/gcc/tree-vect-data-refs.c b/gcc/tree-vect-data-refs.c
index 1a49423..2814738 100644
--- a/gcc/tree-vect-data-refs.c
+++ b/gcc/tree-vect-data-refs.c
@@ -1495,12 +1495,19 @@ vect_enhance_data_refs_alignment (loop_vec_info loop_vinfo)
       stmt = DR_STMT (dr);
       stmt_info = vinfo_for_stmt (stmt);
 
+      if (!STMT_VINFO_RELEVANT (stmt_info))
+	continue;
+
       /* For interleaving, only the alignment of the first access
          matters.  */
       if (STMT_VINFO_STRIDED_ACCESS (stmt_info)
           && GROUP_FIRST_ELEMENT (stmt_info) != stmt)
         continue;
 
+      /* For invariant accesses there is nothing to enhance.  */
+      if (integer_zerop (DR_STEP (dr)))
+	continue;
+
       supportable_dr_alignment = vect_supportable_dr_alignment (dr, true);
       do_peeling = vector_alignment_reachable_p (dr);
       if (do_peeling)
@@ -2304,7 +2311,10 @@ vect_analyze_data_ref_access (struct data_reference *dr)
 
   /* Allow invariant loads in loops.  */
   if (loop_vinfo && dr_step == 0)
-    return DR_IS_READ (dr);
+    {
+      GROUP_FIRST_ELEMENT (vinfo_for_stmt (stmt)) = NULL;
+      return DR_IS_READ (dr);
+    }
 
   if (loop && nested_in_vect_loop_p (loop, stmt))
     {