OSDN Git Service

2007-07-09 Thomas Koenig <tkoenig@gcc.gnu.org>
[pf3gnuchains/gcc-fork.git] / gcc / tree-vect-analyze.c
index c53c34e..2b8f318 100644 (file)
@@ -1,5 +1,5 @@
 /* Analysis Utilities for Loop Vectorization.
-   Copyright (C) 2003,2004,2005,2006 Free Software Foundation, Inc.
+   Copyright (C) 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
    Contributed by Dorit Naishlos <dorit@il.ibm.com>
 
 This file is part of GCC.
@@ -97,8 +97,12 @@ vect_determine_vectorization_factor (loop_vec_info loop_vinfo)
   int nbbs = loop->num_nodes;
   block_stmt_iterator si;
   unsigned int vectorization_factor = 0;
-  int i;
   tree scalar_type;
+  tree phi;
+  tree vectype;
+  unsigned int nunits;
+  stmt_vec_info stmt_info;
+  int i;
 
   if (vect_print_dump_info (REPORT_DETAILS))
     fprintf (vect_dump, "=== vect_determine_vectorization_factor ===");
@@ -107,12 +111,61 @@ vect_determine_vectorization_factor (loop_vec_info loop_vinfo)
     {
       basic_block bb = bbs[i];
 
+      for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
+       {
+         stmt_info = vinfo_for_stmt (phi);
+         if (vect_print_dump_info (REPORT_DETAILS))
+           {
+             fprintf (vect_dump, "==> examining phi: ");
+             print_generic_expr (vect_dump, phi, TDF_SLIM);
+           }
+
+         gcc_assert (stmt_info);
+
+         if (STMT_VINFO_RELEVANT_P (stmt_info))
+            {
+             gcc_assert (!STMT_VINFO_VECTYPE (stmt_info));
+              scalar_type = TREE_TYPE (PHI_RESULT (phi));
+
+             if (vect_print_dump_info (REPORT_DETAILS))
+               {
+                 fprintf (vect_dump, "get vectype for scalar type:  ");
+                 print_generic_expr (vect_dump, scalar_type, TDF_SLIM);
+               }
+
+             vectype = get_vectype_for_scalar_type (scalar_type);
+             if (!vectype)
+               {
+                 if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
+                   {
+                     fprintf (vect_dump,
+                              "not vectorized: unsupported data-type ");
+                     print_generic_expr (vect_dump, scalar_type, TDF_SLIM);
+                   }
+                 return false;
+               }
+             STMT_VINFO_VECTYPE (stmt_info) = vectype;
+
+             if (vect_print_dump_info (REPORT_DETAILS))
+               {
+                 fprintf (vect_dump, "vectype: ");
+                 print_generic_expr (vect_dump, vectype, TDF_SLIM);
+               }
+
+             nunits = TYPE_VECTOR_SUBPARTS (vectype);
+             if (vect_print_dump_info (REPORT_DETAILS))
+               fprintf (vect_dump, "nunits = %d", nunits);
+
+             if (!vectorization_factor
+                 || (nunits > vectorization_factor))
+               vectorization_factor = nunits;
+           }
+       }
+
       for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
         {
          tree stmt = bsi_stmt (si);
-         unsigned int nunits;
-         stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
-         tree vectype;
+         stmt_info = vinfo_for_stmt (stmt);
 
          if (vect_print_dump_info (REPORT_DETAILS))
            {
@@ -120,9 +173,6 @@ vect_determine_vectorization_factor (loop_vec_info loop_vinfo)
              print_generic_expr (vect_dump, stmt, TDF_SLIM);
            }
 
-         if (TREE_CODE (stmt) != GIMPLE_MODIFY_STMT)
-           continue;
-
          gcc_assert (stmt_info);
 
          /* skip stmts which do not need to be vectorized.  */
@@ -134,6 +184,16 @@ vect_determine_vectorization_factor (loop_vec_info loop_vinfo)
              continue;
            }
 
+         if (TREE_CODE (stmt) != GIMPLE_MODIFY_STMT)
+           {
+             if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
+               {
+                 fprintf (vect_dump, "not vectorized: irregular stmt.");
+                 print_generic_expr (vect_dump, stmt, TDF_SLIM);
+               }
+             return false;
+           }
+
          if (!GIMPLE_STMT_P (stmt)
              && VECTOR_MODE_P (TYPE_MODE (TREE_TYPE (stmt))))
            {
@@ -164,7 +224,7 @@ vect_determine_vectorization_factor (loop_vec_info loop_vinfo)
                 arguments (e.g. demotion, promotion), vectype will be reset 
                 appropriately (later).  Note that we have to visit the smallest 
                 datatype in this function, because that determines the VF.  
-                If the samallest datatype in the loop is present only as the 
+                If the smallest datatype in the loop is present only as the 
                 rhs of a promotion operation - we'd miss it here.
                 However, in such a case, that a variable of this datatype
                 does not appear in the lhs anywhere in the loop, it shouldn't
@@ -209,7 +269,8 @@ vect_determine_vectorization_factor (loop_vec_info loop_vinfo)
     }
 
   /* TODO: Analyze cost. Decide if worth while to vectorize.  */
-
+  if (vect_print_dump_info (REPORT_DETAILS))
+    fprintf (vect_dump, "vectorization factor = %d", vectorization_factor);
   if (vectorization_factor <= 1)
     {
       if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
@@ -239,6 +300,9 @@ vect_analyze_operations (loop_vec_info loop_vinfo)
   tree phi;
   stmt_vec_info stmt_info;
   bool need_to_vectorize = false;
+  int min_profitable_iters;
+  int min_scalar_loop_bound;
+  unsigned int th;
 
   if (vect_print_dump_info (REPORT_DETAILS))
     fprintf (vect_dump, "=== vect_analyze_operations ===");
@@ -252,6 +316,8 @@ vect_analyze_operations (loop_vec_info loop_vinfo)
 
       for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
         {
+         ok = true;
+
          stmt_info = vinfo_for_stmt (phi);
          if (vect_print_dump_info (REPORT_DETAILS))
            {
@@ -266,16 +332,34 @@ vect_analyze_operations (loop_vec_info loop_vinfo)
              /* FORNOW: not yet supported.  */
              if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
                fprintf (vect_dump, "not vectorized: value used after loop.");
-           return false;
-         }
+             return false;
+           }
+
+         if (STMT_VINFO_RELEVANT (stmt_info) == vect_used_in_loop
+             && STMT_VINFO_DEF_TYPE (stmt_info) != vect_induction_def)
+           {
+             /* A scalar-dependence cycle that we don't support.  */
+             if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
+               fprintf (vect_dump, "not vectorized: scalar dependence cycle.");
+             return false;
+           }
 
          if (STMT_VINFO_RELEVANT_P (stmt_info))
            {
-             /* Most likely a reduction-like computation that is used
-                in the loop.  */
+             need_to_vectorize = true;
+             if (STMT_VINFO_DEF_TYPE (stmt_info) == vect_induction_def)
+               ok = vectorizable_induction (phi, NULL, NULL);
+           }
+
+         if (!ok)
+           {
              if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
-               fprintf (vect_dump, "not vectorized: unsupported pattern.");
-            return false;
+               {
+                 fprintf (vect_dump,
+                          "not vectorized: relevant phi not supported: ");
+                 print_generic_expr (vect_dump, phi, TDF_SLIM);
+               }
+             return false;
            }
        }
 
@@ -283,6 +367,7 @@ vect_analyze_operations (loop_vec_info loop_vinfo)
        {
          tree stmt = bsi_stmt (si);
          stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
+         enum vect_def_type relevance = STMT_VINFO_RELEVANT (stmt_info);
 
          if (vect_print_dump_info (REPORT_DETAILS))
            {
@@ -307,59 +392,60 @@ vect_analyze_operations (loop_vec_info loop_vinfo)
              continue;
            }
 
-          if (STMT_VINFO_RELEVANT_P (stmt_info))
-            {
-              gcc_assert (GIMPLE_STMT_P (stmt)
-                         || !VECTOR_MODE_P (TYPE_MODE (TREE_TYPE (stmt))));
-              gcc_assert (STMT_VINFO_VECTYPE (stmt_info));
-
-             ok = (vectorizable_type_promotion (stmt, NULL, NULL)
-                   || vectorizable_type_demotion (stmt, NULL, NULL)
-                   || vectorizable_operation (stmt, NULL, NULL)
-                   || vectorizable_assignment (stmt, NULL, NULL)
-                   || vectorizable_load (stmt, NULL, NULL)
-                   || vectorizable_call (stmt, NULL, NULL)
-                   || vectorizable_store (stmt, NULL, NULL)
-                   || vectorizable_condition (stmt, NULL, NULL));
-
-             if (!ok)
-               {
-                 if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
-                   {
-                     fprintf (vect_dump, 
-                              "not vectorized: relevant stmt not supported: ");
-                     print_generic_expr (vect_dump, stmt, TDF_SLIM);
-                   }
-                 return false;
-               }       
-             need_to_vectorize = true;
-            }
-
-         if (STMT_VINFO_LIVE_P (stmt_info))
+         switch (STMT_VINFO_DEF_TYPE (stmt_info))
            {
-             ok = vectorizable_reduction (stmt, NULL, NULL);
+           case vect_loop_def:
+             break;
+       
+           case vect_reduction_def:
+             gcc_assert (relevance == vect_unused_in_loop);
+             break;    
+
+           case vect_induction_def:
+           case vect_constant_def:
+           case vect_invariant_def:
+           case vect_unknown_def_type:
+           default:
+             gcc_unreachable ();       
+           }
 
-             if (ok)
-                need_to_vectorize = true;
-              else
-               ok = vectorizable_live_operation (stmt, NULL, NULL);
+         if (STMT_VINFO_RELEVANT_P (stmt_info))
+           {
+             gcc_assert (GIMPLE_STMT_P (stmt)
+                         || !VECTOR_MODE_P (TYPE_MODE (TREE_TYPE (stmt))));
+             gcc_assert (STMT_VINFO_VECTYPE (stmt_info));
+             need_to_vectorize = true;
+           }
 
-             if (!ok)
+         ok = (vectorizable_type_promotion (stmt, NULL, NULL)
+               || vectorizable_type_demotion (stmt, NULL, NULL)
+               || vectorizable_conversion (stmt, NULL, NULL)
+               || vectorizable_operation (stmt, NULL, NULL)
+               || vectorizable_assignment (stmt, NULL, NULL)
+               || vectorizable_load (stmt, NULL, NULL)
+               || vectorizable_call (stmt, NULL, NULL)
+               || vectorizable_store (stmt, NULL, NULL)
+               || vectorizable_condition (stmt, NULL, NULL)
+               || vectorizable_reduction (stmt, NULL, NULL));
+
+         /* Stmts that are (also) "live" (i.e. - that are used out of the loop)
+            need extra handling, except for vectorizable reductions.  */
+         if (STMT_VINFO_LIVE_P (stmt_info)
+             && STMT_VINFO_TYPE (stmt_info) != reduc_vec_info_type) 
+           ok |= vectorizable_live_operation (stmt, NULL, NULL);
+
+         if (!ok)
+           {
+             if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
                {
-                 if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
-                   {
-                     fprintf (vect_dump, 
-                              "not vectorized: live stmt not supported: ");
-                     print_generic_expr (vect_dump, stmt, TDF_SLIM);
-                   }
-                 return false;
+                 fprintf (vect_dump, "not vectorized: stmt not supported: ");
+                 print_generic_expr (vect_dump, stmt, TDF_SLIM);
                }
-           }
+             return false;
+           }   
        } /* stmts in bb */
     } /* bbs */
 
-  /* TODO: Analyze cost. Decide if worth while to vectorize.  */
-
   /* All operations in the loop are either irrelevant (deal with loop
      control, or dead), or only used outside the loop and can be moved
      out of the loop (e.g. invariants, inductions).  The loop can be 
@@ -383,16 +469,55 @@ vect_analyze_operations (loop_vec_info loop_vinfo)
         vectorization_factor, LOOP_VINFO_INT_NITERS (loop_vinfo));
 
   if (LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo)
-      && ((LOOP_VINFO_INT_NITERS (loop_vinfo) < vectorization_factor)
-         || (LOOP_VINFO_INT_NITERS (loop_vinfo) <=
-               ((unsigned) (PARAM_VALUE (PARAM_MIN_VECT_LOOP_BOUND)) 
-                                          * vectorization_factor))))
+      && (LOOP_VINFO_INT_NITERS (loop_vinfo) < vectorization_factor))
+    {
+      if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
+        fprintf (vect_dump, "not vectorized: iteration count too small.");
+      if (vect_print_dump_info (REPORT_DETAILS))
+        fprintf (vect_dump,"not vectorized: iteration count smaller than "
+                 "vectorization factor.");
+      return false;
+    }
+
+  /* Analyze cost. Decide if worth while to vectorize.  */
+
+  min_profitable_iters = vect_estimate_min_profitable_iters (loop_vinfo);
+  LOOP_VINFO_COST_MODEL_MIN_ITERS (loop_vinfo) = min_profitable_iters;
+  if (min_profitable_iters < 0)
     {
       if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
-       fprintf (vect_dump, "not vectorized: iteration count too small.");
+        fprintf (vect_dump, "not vectorized: vectorization not profitable.");
+      if (vect_print_dump_info (REPORT_DETAILS))
+        fprintf (vect_dump, "not vectorized: vector version will never be "
+                 "profitable.");
       return false;
     }
 
+  min_scalar_loop_bound = (PARAM_VALUE (PARAM_MIN_VECT_LOOP_BOUND))
+                          * vectorization_factor;
+
+  /* Use the cost model only if it is more conservative than user specified
+     threshold.  */
+
+  th = (unsigned) min_scalar_loop_bound;
+  if (min_profitable_iters 
+      && (!min_scalar_loop_bound
+          || min_profitable_iters > min_scalar_loop_bound))
+    th = (unsigned) min_profitable_iters;
+
+  if (LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo)
+      && LOOP_VINFO_INT_NITERS (loop_vinfo) < th)
+    {
+      if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))          
+        fprintf (vect_dump, "not vectorized: vectorization not "
+                 "profitable.");
+      if (vect_print_dump_info (REPORT_DETAILS))             
+        fprintf (vect_dump, "not vectorized: iteration count smaller than "
+                 "user specified loop bound parameter or minimum "
+                 "profitable iterations (whichever is more conservative).");
+      return false;
+    }  
+
   if (!LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo)
       || LOOP_VINFO_INT_NITERS (loop_vinfo) % vectorization_factor != 0
       || LOOP_PEELING_FOR_ALIGNMENT (loop_vinfo))
@@ -509,58 +634,69 @@ vect_analyze_scalar_cycles (loop_vec_info loop_vinfo)
   tree phi;
   struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
   basic_block bb = loop->header;
-  tree dummy;
+  tree dumy;
+  VEC(tree,heap) *worklist = VEC_alloc (tree, heap, 64);
 
   if (vect_print_dump_info (REPORT_DETAILS))
     fprintf (vect_dump, "=== vect_analyze_scalar_cycles ===");
 
+  /* First - identify all inductions.  */
   for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
     {
       tree access_fn = NULL;
       tree def = PHI_RESULT (phi);
       stmt_vec_info stmt_vinfo = vinfo_for_stmt (phi);
-      tree reduc_stmt;
 
       if (vect_print_dump_info (REPORT_DETAILS))
        {
-          fprintf (vect_dump, "Analyze phi: ");
-          print_generic_expr (vect_dump, phi, TDF_SLIM);
+         fprintf (vect_dump, "Analyze phi: ");
+         print_generic_expr (vect_dump, phi, TDF_SLIM);
        }
 
       /* Skip virtual phi's. The data dependences that are associated with
          virtual defs/uses (i.e., memory accesses) are analyzed elsewhere.  */
-
       if (!is_gimple_reg (SSA_NAME_VAR (def)))
-       {
-         if (vect_print_dump_info (REPORT_DETAILS))
-           fprintf (vect_dump, "virtual phi. skip.");
-         continue;
-       }
+       continue;
 
       STMT_VINFO_DEF_TYPE (stmt_vinfo) = vect_unknown_def_type;
 
       /* Analyze the evolution function.  */
-
       access_fn = analyze_scalar_evolution (loop, def);
+      if (access_fn && vect_print_dump_info (REPORT_DETAILS))
+       {
+         fprintf (vect_dump, "Access function of PHI: ");
+         print_generic_expr (vect_dump, access_fn, TDF_SLIM);
+       }
 
-      if (!access_fn)
-       continue;
+      if (!access_fn
+         || !vect_is_simple_iv_evolution (loop->num, access_fn, &dumy, &dumy)) 
+       {
+         VEC_safe_push (tree, heap, worklist, phi);      
+         continue;
+       }
 
       if (vect_print_dump_info (REPORT_DETAILS))
-        {
-           fprintf (vect_dump, "Access function of PHI: ");
-           print_generic_expr (vect_dump, access_fn, TDF_SLIM);
-        }
+       fprintf (vect_dump, "Detected induction.");
+      STMT_VINFO_DEF_TYPE (stmt_vinfo) = vect_induction_def;
+    }
 
-      if (vect_is_simple_iv_evolution (loop->num, access_fn, &dummy, &dummy))
-       {
-         if (vect_print_dump_info (REPORT_DETAILS))
-           fprintf (vect_dump, "Detected induction.");
-         STMT_VINFO_DEF_TYPE (stmt_vinfo) = vect_induction_def;
-          continue;
-       }
 
-      /* TODO: handle invariant phis  */
+  /* Second - identify all reductions.  */
+  while (VEC_length (tree, worklist) > 0)
+    {
+      tree phi = VEC_pop (tree, worklist);
+      tree def = PHI_RESULT (phi);
+      stmt_vec_info stmt_vinfo = vinfo_for_stmt (phi);
+      tree reduc_stmt;
+
+      if (vect_print_dump_info (REPORT_DETAILS))
+        { 
+          fprintf (vect_dump, "Analyze phi: ");
+          print_generic_expr (vect_dump, phi, TDF_SLIM);
+        }
+
+      gcc_assert (is_gimple_reg (SSA_NAME_VAR (def)));
+      gcc_assert (STMT_VINFO_DEF_TYPE (stmt_vinfo) == vect_unknown_def_type);
 
       reduc_stmt = vect_is_simple_reduction (loop, phi);
       if (reduc_stmt)
@@ -574,9 +710,9 @@ vect_analyze_scalar_cycles (loop_vec_info loop_vinfo)
       else
         if (vect_print_dump_info (REPORT_DETAILS))
           fprintf (vect_dump, "Unknown def-use cycle pattern.");
-
     }
 
+  VEC_free (tree, heap, worklist);
   return;
 }
 
@@ -1039,17 +1175,16 @@ vect_compute_data_ref_alignment (struct data_reference *dr)
     fprintf (vect_dump, "vect_compute_data_ref_alignment:");
 
   /* Initialize misalignment to unknown.  */
-  DR_MISALIGNMENT (dr) = -1;
+  SET_DR_MISALIGNMENT (dr, -1);
 
-  misalign = DR_OFFSET_MISALIGNMENT (dr);
+  misalign = DR_INIT (dr);
   aligned_to = DR_ALIGNED_TO (dr);
   base_addr = DR_BASE_ADDRESS (dr);
   base = build_fold_indirect_ref (base_addr);
   vectype = STMT_VINFO_VECTYPE (stmt_info);
   alignment = ssize_int (TYPE_ALIGN (vectype)/BITS_PER_UNIT);
 
-  if ((aligned_to && tree_int_cst_compare (aligned_to, alignment) < 0)
-      || !misalign)
+  if (tree_int_cst_compare (aligned_to, alignment) < 0)
     {
       if (vect_print_dump_info (REPORT_DETAILS))
        {
@@ -1110,7 +1245,7 @@ vect_compute_data_ref_alignment (struct data_reference *dr)
       return false;
     }
 
-  DR_MISALIGNMENT (dr) = TREE_INT_CST_LOW (misalign);
+  SET_DR_MISALIGNMENT (dr, TREE_INT_CST_LOW (misalign));
 
   if (vect_print_dump_info (REPORT_DETAILS))
     {
@@ -1169,15 +1304,6 @@ vect_update_misalignment_for_peel (struct data_reference *dr,
   if (DR_GROUP_FIRST_DR (peel_stmt_info))
     dr_peel_size *= DR_GROUP_SIZE (peel_stmt_info);
 
-  if (known_alignment_for_access_p (dr)
-      && known_alignment_for_access_p (dr_peel)
-      && (DR_MISALIGNMENT (dr) / dr_size ==
-          DR_MISALIGNMENT (dr_peel) / dr_peel_size))
-    {
-      DR_MISALIGNMENT (dr) = 0;
-      return;
-    }
-
   /* It can be assumed that the data refs with the same alignment as dr_peel
      are aligned in the vector loop.  */
   same_align_drs
@@ -1188,21 +1314,23 @@ vect_update_misalignment_for_peel (struct data_reference *dr,
         continue;
       gcc_assert (DR_MISALIGNMENT (dr) / dr_size ==
                   DR_MISALIGNMENT (dr_peel) / dr_peel_size);
-      DR_MISALIGNMENT (dr) = 0;
+      SET_DR_MISALIGNMENT (dr, 0);
       return;
     }
 
   if (known_alignment_for_access_p (dr)
       && known_alignment_for_access_p (dr_peel))
     {
-      DR_MISALIGNMENT (dr) += npeel * dr_size;
-      DR_MISALIGNMENT (dr) %= UNITS_PER_SIMD_WORD;
+      int misal = DR_MISALIGNMENT (dr);
+      misal += npeel * dr_size;
+      misal %= UNITS_PER_SIMD_WORD;
+      SET_DR_MISALIGNMENT (dr, misal);
       return;
     }
 
   if (vect_print_dump_info (REPORT_DETAILS))
     fprintf (vect_dump, "Setting misalignment to -1.");
-  DR_MISALIGNMENT (dr) = -1;
+  SET_DR_MISALIGNMENT (dr, -1);
 }
 
 
@@ -1346,6 +1474,7 @@ static bool
 vect_enhance_data_refs_alignment (loop_vec_info loop_vinfo)
 {
   VEC (data_reference_p, heap) *datarefs = LOOP_VINFO_DATAREFS (loop_vinfo);
+  struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
   enum dr_alignment_support supportable_dr_alignment;
   struct data_reference *dr0 = NULL;
   struct data_reference *dr;
@@ -1366,7 +1495,7 @@ vect_enhance_data_refs_alignment (loop_vec_info loop_vinfo)
         can make all data references satisfy vect_supportable_dr_alignment.
         If so, update data structures as needed and return true.  Note that
         at this time vect_supportable_dr_alignment is known to return false
-        for a misaligned write.
+        for a misaligned write.
 
      B) If peeling wasn't possible and there is a data reference with an
         unknown misalignment that does not satisfy vect_supportable_dr_alignment
@@ -1417,7 +1546,8 @@ vect_enhance_data_refs_alignment (loop_vec_info loop_vinfo)
                 the prolog loop ({VF - misalignment}), is a multiple of the
                 number of the interleaved accesses.  */
              int elem_size, mis_in_elements;
-             int vf = LOOP_VINFO_VECT_FACTOR (loop_vinfo);
+             tree vectype = STMT_VINFO_VECTYPE (stmt_info);
+             int nelements = TYPE_VECTOR_SUBPARTS (vectype);
 
              /* FORNOW: handle only known alignment.  */
              if (!known_alignment_for_access_p (dr))
@@ -1426,10 +1556,10 @@ vect_enhance_data_refs_alignment (loop_vec_info loop_vinfo)
                  break;
                }
 
-             elem_size = UNITS_PER_SIMD_WORD / vf;
+             elem_size = UNITS_PER_SIMD_WORD / nelements;
              mis_in_elements = DR_MISALIGNMENT (dr) / elem_size;
 
-             if ((vf - mis_in_elements) % DR_GROUP_SIZE (stmt_info))
+             if ((nelements - mis_in_elements) % DR_GROUP_SIZE (stmt_info))
                {
                  do_peeling = false;
                  break;
@@ -1443,13 +1573,18 @@ vect_enhance_data_refs_alignment (loop_vec_info loop_vinfo)
 
   /* Often peeling for alignment will require peeling for loop-bound, which in 
      turn requires that we know how to adjust the loop ivs after the loop.  */
-  if (!vect_can_advance_ivs_p (loop_vinfo))
+  if (!vect_can_advance_ivs_p (loop_vinfo)
+      || !slpeel_can_duplicate_loop_p (loop, single_exit (loop)))
     do_peeling = false;
 
   if (do_peeling)
     {
       int mis;
       int npeel = 0;
+      tree stmt = DR_STMT (dr0);
+      stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
+      tree vectype = STMT_VINFO_VECTYPE (stmt_info);
+      int nelements = TYPE_VECTOR_SUBPARTS (vectype);
 
       if (known_alignment_for_access_p (dr0))
         {
@@ -1459,7 +1594,7 @@ vect_enhance_data_refs_alignment (loop_vec_info loop_vinfo)
              factor minus the misalignment as an element count.  */
           mis = DR_MISALIGNMENT (dr0);
           mis /= GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (DR_REF (dr0))));
-          npeel = LOOP_VINFO_VECT_FACTOR (loop_vinfo) - mis;
+          npeel = nelements - mis;
 
          /* For interleaved data access every iteration accesses all the 
             members of the group, therefore we divide the number of iterations
@@ -1491,7 +1626,7 @@ vect_enhance_data_refs_alignment (loop_vec_info loop_vinfo)
          save_misalignment = DR_MISALIGNMENT (dr);
          vect_update_misalignment_for_peel (dr, dr0, npeel);
          supportable_dr_alignment = vect_supportable_dr_alignment (dr);
-         DR_MISALIGNMENT (dr) = save_misalignment;
+         SET_DR_MISALIGNMENT (dr, save_misalignment);
          
          if (!supportable_dr_alignment)
            {
@@ -1515,7 +1650,7 @@ vect_enhance_data_refs_alignment (loop_vec_info loop_vinfo)
 
           LOOP_VINFO_UNALIGNED_DR (loop_vinfo) = dr0;
           LOOP_PEELING_FOR_ALIGNMENT (loop_vinfo) = DR_MISALIGNMENT (dr0);
-          DR_MISALIGNMENT (dr0) = 0;
+         SET_DR_MISALIGNMENT (dr0, 0);
          if (vect_print_dump_info (REPORT_ALIGNMENT))
             fprintf (vect_dump, "Alignment of access forced using peeling.");
 
@@ -1616,7 +1751,7 @@ vect_enhance_data_refs_alignment (loop_vec_info loop_vinfo)
         {
           stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
           dr = STMT_VINFO_DATA_REF (stmt_info);
-          DR_MISALIGNMENT (dr) = 0;
+         SET_DR_MISALIGNMENT (dr, 0);
          if (vect_print_dump_info (REPORT_ALIGNMENT))
             fprintf (vect_dump, "Alignment of access forced using versioning.");
         }
@@ -1740,7 +1875,7 @@ vect_analyze_data_ref_access (struct data_reference *dr)
        {
          /* Skip same data-refs. In case that two or more stmts share data-ref
             (supported only for loads), we vectorize only the first stmt, and
-            the rest get their vectorized loads from the the first one.  */
+            the rest get their vectorized loads from the first one.  */
          if (!tree_int_cst_compare (DR_INIT (data_ref),
                                     DR_INIT (STMT_VINFO_DATA_REF (
                                                      vinfo_for_stmt (next)))))
@@ -1752,7 +1887,7 @@ vect_analyze_data_ref_access (struct data_reference *dr)
                   return false; 
                 }
 
-              /* Check that there is no load-store dependecies for this loads 
+              /* Check that there is no load-store dependencies for this loads 
                  to prevent a case of load-store-load to the same location.  */
               if (DR_GROUP_READ_WRITE_DEPENDENCE (vinfo_for_stmt (next))
                   || DR_GROUP_READ_WRITE_DEPENDENCE (vinfo_for_stmt (prev)))
@@ -1908,7 +2043,7 @@ vect_analyze_data_refs (loop_vec_info loop_vinfo)
   tree scalar_type;
 
   if (vect_print_dump_info (REPORT_DETAILS))
-    fprintf (vect_dump, "=== vect_analyze_data_refs ===");
+    fprintf (vect_dump, "=== vect_analyze_data_refs ===\n");
 
   compute_data_dependences_for_loop (loop, true,
                                      &LOOP_VINFO_DATAREFS (loop_vinfo),
@@ -1933,7 +2068,7 @@ vect_analyze_data_refs (loop_vec_info loop_vinfo)
       /* Update DR field in stmt_vec_info struct.  */
       stmt = DR_STMT (dr);
       stmt_info = vinfo_for_stmt (stmt);
-  
+
       if (STMT_VINFO_DATA_REF (stmt_info))
         {
           if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
@@ -1957,7 +2092,16 @@ vect_analyze_data_refs (loop_vec_info loop_vinfo)
             }
           return false;
         }
-      if (!DR_MEMTAG (dr))
+
+      if (TREE_CODE (DR_BASE_ADDRESS (dr)) == INTEGER_CST)
+        {
+          if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
+            fprintf (vect_dump, "not vectorized: base addr of dr is a "
+                     "constant");
+          return false;
+        }
+
+      if (!DR_SYMBOL_TAG (dr))
         {
           if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
             {
@@ -2028,11 +2172,6 @@ vect_mark_relevant (VEC(tree,heap) **worklist, tree stmt,
   if (relevant > STMT_VINFO_RELEVANT (stmt_info))
     STMT_VINFO_RELEVANT (stmt_info) = relevant;
 
-  if (TREE_CODE (stmt) == PHI_NODE)
-    /* Don't put phi-nodes in the worklist. Phis that are marked relevant
-       or live will fail vectorization later on.  */
-    return;
-
   if (STMT_VINFO_RELEVANT (stmt_info) == save_relevant
       && STMT_VINFO_LIVE_P (stmt_info) == save_live_p)
     {
@@ -2108,6 +2247,81 @@ vect_stmt_relevant_p (tree stmt, loop_vec_info loop_vinfo,
 }
 
 
+/* 
+   Function process_use.
+
+   Inputs:
+   - a USE in STMT in a loop represented by LOOP_VINFO
+   - LIVE_P, RELEVANT - enum values to be set in the STMT_VINFO of the stmt 
+     that defined USE. This is dont by calling mark_relevant and passing it
+     the WORKLIST (to add DEF_STMT to the WORKlist in case itis relevant). 
+
+   Outputs:
+   Generally, LIVE_P and RELEVANT are used to define the liveness and
+   relevance info of the DEF_STMT of this USE:
+       STMT_VINFO_LIVE_P (DEF_STMT_info) <-- live_p
+       STMT_VINFO_RELEVANT (DEF_STMT_info) <-- relevant
+   Exceptions:
+   - case 1: If USE is used only for address computations (e.g. array indexing),
+   which does not need to be directly vectorized, then the liveness/relevance 
+   of the respective DEF_STMT is left unchanged.
+   - case 2: If STMT is a reduction phi and DEF_STMT is a reduction stmt, we 
+   skip DEF_STMT cause it had already been processed.  
+
+   Return true if everything is as expected. Return false otherwise.  */
+
+static bool
+process_use (tree stmt, tree use, loop_vec_info loop_vinfo, bool live_p, 
+            enum vect_relevant relevant, VEC(tree,heap) **worklist)
+{
+  struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
+  stmt_vec_info stmt_vinfo = vinfo_for_stmt (stmt);
+  stmt_vec_info dstmt_vinfo;
+  basic_block def_bb;
+  tree def, def_stmt;
+  enum vect_def_type dt;
+
+  /* case 1: we are only interested in uses that need to be vectorized.  Uses 
+     that are used for address computation are not considered relevant.  */
+  if (!exist_non_indexing_operands_for_use_p (use, stmt))
+     return true;
+
+  if (!vect_is_simple_use (use, loop_vinfo, &def_stmt, &def, &dt))
+    { 
+      if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
+        fprintf (vect_dump, "not vectorized: unsupported use in stmt.");
+      return false;
+    }
+
+  if (!def_stmt || IS_EMPTY_STMT (def_stmt))
+    return true;
+
+  def_bb = bb_for_stmt (def_stmt);
+  if (!flow_bb_inside_loop_p (loop, def_bb))
+    return true;
+
+  /* case 2: A reduction phi defining a reduction stmt (DEF_STMT). DEF_STMT 
+     must have already been processed, so we just check that everything is as 
+     expected, and we are done.  */
+  dstmt_vinfo = vinfo_for_stmt (def_stmt);
+  if (TREE_CODE (stmt) == PHI_NODE
+      && STMT_VINFO_DEF_TYPE (stmt_vinfo) == vect_reduction_def
+      && TREE_CODE (def_stmt) != PHI_NODE
+      && STMT_VINFO_DEF_TYPE (dstmt_vinfo) == vect_reduction_def)
+    {
+      if (STMT_VINFO_IN_PATTERN_P (dstmt_vinfo))
+       dstmt_vinfo = vinfo_for_stmt (STMT_VINFO_RELATED_STMT (dstmt_vinfo));
+      gcc_assert (STMT_VINFO_RELEVANT (dstmt_vinfo) < vect_used_by_reduction);
+      gcc_assert (STMT_VINFO_LIVE_P (dstmt_vinfo) 
+                 || STMT_VINFO_RELEVANT (dstmt_vinfo) > vect_unused_in_loop);
+      return true;
+    }
+
+  vect_mark_relevant (worklist, def_stmt, relevant, live_p);
+  return true;
+}
+
+
 /* Function vect_mark_stmts_to_be_vectorized.
 
    Not all stmts in the loop need to be vectorized. For example:
@@ -2132,17 +2346,14 @@ vect_mark_stmts_to_be_vectorized (loop_vec_info loop_vinfo)
   basic_block *bbs = LOOP_VINFO_BBS (loop_vinfo);
   unsigned int nbbs = loop->num_nodes;
   block_stmt_iterator si;
-  tree stmt, use;
+  tree stmt;
   stmt_ann_t ann;
-  ssa_op_iter iter;
   unsigned int i;
   stmt_vec_info stmt_vinfo;
   basic_block bb;
   tree phi;
   bool live_p;
   enum vect_relevant relevant;
-  tree def, def_stmt;
-  enum vect_def_type dt;
 
   if (vect_print_dump_info (REPORT_DETAILS))
     fprintf (vect_dump, "=== vect_mark_stmts_to_be_vectorized ===");
@@ -2150,27 +2361,23 @@ vect_mark_stmts_to_be_vectorized (loop_vec_info loop_vinfo)
   worklist = VEC_alloc (tree, heap, 64);
 
   /* 1. Init worklist.  */
-
-  bb = loop->header;
-  for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
-    {
-      if (vect_print_dump_info (REPORT_DETAILS))
-        {
-          fprintf (vect_dump, "init: phi relevant? ");
-          print_generic_expr (vect_dump, phi, TDF_SLIM);
-        }
-
-      if (vect_stmt_relevant_p (phi, loop_vinfo, &relevant, &live_p))
-       vect_mark_relevant (&worklist, phi, relevant, live_p);
-    }
-
   for (i = 0; i < nbbs; i++)
     {
       bb = bbs[i];
+      for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
+       { 
+         if (vect_print_dump_info (REPORT_DETAILS))
+           {
+             fprintf (vect_dump, "init: phi relevant? ");
+             print_generic_expr (vect_dump, phi, TDF_SLIM);
+           }
+
+         if (vect_stmt_relevant_p (phi, loop_vinfo, &relevant, &live_p))
+           vect_mark_relevant (&worklist, phi, relevant, live_p);
+       }
       for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
        {
          stmt = bsi_stmt (si);
-
          if (vect_print_dump_info (REPORT_DETAILS))
            {
              fprintf (vect_dump, "init: stmt relevant? ");
@@ -2182,118 +2389,82 @@ vect_mark_stmts_to_be_vectorized (loop_vec_info loop_vinfo)
        }
     }
 
-
   /* 2. Process_worklist */
-
   while (VEC_length (tree, worklist) > 0)
     {
-      stmt = VEC_pop (tree, worklist);
+      use_operand_p use_p;
+      ssa_op_iter iter;
 
+      stmt = VEC_pop (tree, worklist);
       if (vect_print_dump_info (REPORT_DETAILS))
        {
           fprintf (vect_dump, "worklist: examine stmt: ");
           print_generic_expr (vect_dump, stmt, TDF_SLIM);
        }
 
-      /* Examine the USEs of STMT. For each ssa-name USE that is defined
-         in the loop, mark the stmt that defines it (DEF_STMT) as
-         relevant/irrelevant and live/dead according to the liveness and
-         relevance properties of STMT.
-       */
-
-      gcc_assert (TREE_CODE (stmt) != PHI_NODE);
-
+      /* Examine the USEs of STMT. For each USE, mark the stmt that defines it 
+        (DEF_STMT) as relevant/irrelevant and live/dead according to the 
+        liveness and relevance properties of STMT.  */
       ann = stmt_ann (stmt);
       stmt_vinfo = vinfo_for_stmt (stmt);
-
       relevant = STMT_VINFO_RELEVANT (stmt_vinfo);
       live_p = STMT_VINFO_LIVE_P (stmt_vinfo);
 
       /* Generally, the liveness and relevance properties of STMT are
-         propagated to the DEF_STMTs of its USEs:
-             STMT_VINFO_LIVE_P (DEF_STMT_info) <-- live_p
-             STMT_VINFO_RELEVANT (DEF_STMT_info) <-- relevant
-
-         Exceptions:
-
-        (case 1)
-           If USE is used only for address computations (e.g. array indexing),
-           which does not need to be directly vectorized, then the
-           liveness/relevance of the respective DEF_STMT is left unchanged.
-
-        (case 2)
-           If STMT has been identified as defining a reduction variable, then
-          we have two cases:
-          (case 2.1)
-            The last use of STMT is the reduction-variable, which is defined
-            by a loop-header-phi. We don't want to mark the phi as live or
-            relevant (because it does not need to be vectorized, it is handled
-             as part of the vectorization of the reduction), so in this case we
-            skip the call to vect_mark_relevant.
-          (case 2.2)
-            The rest of the uses of STMT are defined in the loop body. For
-             the def_stmt of these uses we want to set liveness/relevance
-             as follows:
-               STMT_VINFO_LIVE_P (DEF_STMT_info) <-- false
-               STMT_VINFO_RELEVANT (DEF_STMT_info) <-- vect_used_by_reduction
-             because even though STMT is classified as live (since it defines a
-             value that is used across loop iterations) and irrelevant (since it
-             is not used inside the loop), it will be vectorized, and therefore
-             the corresponding DEF_STMTs need to marked as relevant.
-            We distinguish between two kinds of relevant stmts - those that are
-            used by a reduction computation, and those that are (also) used by
-            a regular computation. This allows us later on to identify stmts
-            that are used solely by a reduction, and therefore the order of 
-            the results that they produce does not have to be kept.
-       */
-
-      /* case 2.2:  */
+        propagated as is to the DEF_STMTs of its USEs:
+         live_p <-- STMT_VINFO_LIVE_P (STMT_VINFO)
+         relevant <-- STMT_VINFO_RELEVANT (STMT_VINFO)
+
+        One exception is when STMT has been identified as defining a reduction
+        variable; in this case we set the liveness/relevance as follows:
+          live_p = false
+          relevant = vect_used_by_reduction
+        This is because we distinguish between two kinds of relevant stmts -
+        those that are used by a reduction computation, and those that are 
+        (also) used by a regular computation. This allows us later on to 
+        identify stmts that are used solely by a reduction, and therefore the 
+        order of the results that they produce does not have to be kept.
+
+         Reduction phis are expected to be used by a reduction stmt;  Other 
+        reduction stmts are expected to be unused in the loop.  These are the 
+        expected values of "relevant" for reduction phis/stmts in the loop:
+
+        relevance:                             phi     stmt
+        vect_unused_in_loop                            ok
+        vect_used_by_reduction                 ok
+        vect_used_in_loop                                                */
+
       if (STMT_VINFO_DEF_TYPE (stmt_vinfo) == vect_reduction_def)
         {
-          gcc_assert (relevant == vect_unused_in_loop && live_p);
-          relevant = vect_used_by_reduction;
-          live_p = false;
-        }
+         switch (relevant)
+           {
+           case vect_unused_in_loop:
+             gcc_assert (TREE_CODE (stmt) != PHI_NODE);
+             break;
+           case vect_used_by_reduction:
+             if (TREE_CODE (stmt) == PHI_NODE)
+               break;
+           case vect_used_in_loop:
+           default:
+             if (vect_print_dump_info (REPORT_DETAILS))
+               fprintf (vect_dump, "unsupported use of reduction.");
+             VEC_free (tree, heap, worklist);
+             return false;
+           }
+         relevant = vect_used_by_reduction;
+         live_p = false;       
+       }
 
-      FOR_EACH_SSA_TREE_OPERAND (use, stmt, iter, SSA_OP_USE)
+      FOR_EACH_PHI_OR_STMT_USE (use_p, stmt, iter, SSA_OP_USE)
        {
-         /* case 1: we are only interested in uses that need to be vectorized. 
-            Uses that are used for address computation are not considered 
-            relevant.
-          */
-         if (!exist_non_indexing_operands_for_use_p (use, stmt))
-           continue;
-
-         if (!vect_is_simple_use (use, loop_vinfo, &def_stmt, &def, &dt))
-            {
-              if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
-                fprintf (vect_dump, "not vectorized: unsupported use in stmt.");
+         tree op = USE_FROM_PTR (use_p);
+         if (!process_use (stmt, op, loop_vinfo, live_p, relevant, &worklist))
+           {
              VEC_free (tree, heap, worklist);
-              return false;
-            }
-
-         if (!def_stmt || IS_EMPTY_STMT (def_stmt))
-           continue;
-
-          if (vect_print_dump_info (REPORT_DETAILS))
-            {
-              fprintf (vect_dump, "worklist: examine use %d: ", i);
-              print_generic_expr (vect_dump, use, TDF_SLIM);
-            }
-
-         bb = bb_for_stmt (def_stmt);
-          if (!flow_bb_inside_loop_p (loop, bb))
-            continue;
-
-         /* case 2.1: the reduction-use does not mark the defining-phi
-            as relevant.  */
-         if (STMT_VINFO_DEF_TYPE (stmt_vinfo) == vect_reduction_def
-             && TREE_CODE (def_stmt) == PHI_NODE)
-           continue;
-
-         vect_mark_relevant (&worklist, def_stmt, relevant, live_p);
+             return false;
+           }
        }
-    }                          /* while worklist */
+    } /* while worklist */
 
   VEC_free (tree, heap, worklist);
   return true;
@@ -2526,10 +2697,7 @@ vect_analyze_loop_form (struct loop *loop)
       return false;
     }
 
-  loop_vinfo = new_loop_vec_info (loop);
-  LOOP_VINFO_NITERS (loop_vinfo) = number_of_iterations;
-
-  if (!LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo))
+  if (!NITERS_KNOWN_P (number_of_iterations))
     {
       if (vect_print_dump_info (REPORT_DETAILS))
         {
@@ -2537,16 +2705,19 @@ vect_analyze_loop_form (struct loop *loop)
           print_generic_expr (vect_dump, number_of_iterations, TDF_DETAILS);
         }
     }
-  else
-  if (LOOP_VINFO_INT_NITERS (loop_vinfo) == 0)
+  else if (TREE_INT_CST_LOW (number_of_iterations) == 0)
     {
       if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
         fprintf (vect_dump, "not vectorized: number of iterations = 0.");
       return NULL;
     }
 
+  loop_vinfo = new_loop_vec_info (loop);
+  LOOP_VINFO_NITERS (loop_vinfo) = number_of_iterations;
   LOOP_VINFO_EXIT_COND (loop_vinfo) = loop_cond;
 
+  gcc_assert (!loop->aux);
+  loop->aux = loop_vinfo;
   return loop_vinfo;
 }