tree-parloops.c (loop_parallel_p): Call vect_is_simple_reduction with additional argument.

	* tree-parloops.c (loop_parallel_p): Call vect_is_simple_reduction
	with additional argument.
	* tree-vectorizer.h (enum vect_def_type): Add 
	vect_double_reduction_def.
	(vect_is_simple_reduction): Add argument.
	* tree-vect-loop.c (vect_determine_vectorization_factor): Fix 
	indentation.
	(vect_analyze_scalar_cycles_1): Detect double reduction. Call
	vect_is_simple_reduction with additional argument.
	(vect_analyze_loop_operations): Handle exit phi nodes in case of
	double reduction.
	(reduction_code_for_scalar_code): Handle additional codes by
	returning ERROR_MARK for them. Fix comment and indentation.
	(vect_is_simple_reduction): Fix comment, add argument to specify
	double reduction. Detect double reduction.
	(get_initial_def_for_induction): Fix indentation.
	(get_initial_def_for_reduction): Fix comment and indentation.
	Handle double reduction. Create initial definitions that do not
	require adjustment if ADJUSTMENT_DEF is NULL. Handle additional cases.
	(vect_create_epilog_for_reduction): Fix comment, add argument to
	handle double reduction. Use PLUS_EXPR in case of MINUS_EXPR in
	epilogue result extraction. Create double reduction phi node and
	replace relevant uses.
	(vectorizable_reduction): Call vect_is_simple_reduction with
	additional argument. Fix indentation. Update epilogue code treatment
	according to the changes in reduction_code_for_scalar_code. Check 
	for double reduction. Call vect_create_epilog_for_reduction with
	additional argument.
	* tree-vect-stmts.c (process_use): Handle double reduction, update
	documentation.
	(vect_mark_stmts_to_be_vectorized): Handle double reduction.
	(vect_get_vec_def_for_operand): Likewise.

From-SVN: r149526

gcc/ChangeLog

+2009-07-12  Ira Rosen  <irar@il.ibm.com>
+
+	* tree-parloops.c (loop_parallel_p): Call vect_is_simple_reduction
+	with additional argument.
+	* tree-vectorizer.h (enum vect_def_type): Add 
+	vect_double_reduction_def.
+	(vect_is_simple_reduction): Add argument.
+	* tree-vect-loop.c (vect_determine_vectorization_factor): Fix 
+	indentation.
+	(vect_analyze_scalar_cycles_1): Detect double reduction. Call
+	vect_is_simple_reduction with additional argument.
+	(vect_analyze_loop_operations): Handle exit phi nodes in case of
+	double reduction.
+	(reduction_code_for_scalar_code): Handle additional codes by
+	returning ERROR_MARK for them. Fix comment and indentation.
+	(vect_is_simple_reduction): Fix comment, add argument to specify
+	double reduction. Detect double reduction.
+	(get_initial_def_for_induction): Fix indentation.
+	(get_initial_def_for_reduction): Fix comment and indentation.
+	Handle double reduction. Create initial definitions that do not
+	require adjustment if ADJUSTMENT_DEF is NULL. Handle additional cases.
+	(vect_create_epilog_for_reduction): Fix comment, add argument to
+	handle double reduction. Use PLUS_EXPR in case of MINUS_EXPR in
+	epilogue result extraction. Create double reduction phi node and
+	replace relevant uses.
+	(vectorizable_reduction): Call vect_is_simple_reduction with
+	additional argument. Fix indentation. Update epilogue code treatment
+	according to the changes in reduction_code_for_scalar_code. Check 
+	for double reduction. Call vect_create_epilog_for_reduction with
+	additional argument.
+	* tree-vect-stmts.c (process_use): Handle double reduction, update
+	documentation.
+	(vect_mark_stmts_to_be_vectorized): Handle double reduction.
+	(vect_get_vec_def_for_operand): Likewise.
+
 2009-07-12  Danny Smith  <dansmister@gmail.com>
 
 	* config/i386/winnt.c (i386_pe_determine_dllexport_p): Don't

gcc/testsuite/ChangeLog

+2009-07-12  Ira Rosen  <irar@il.ibm.com>
+
+	* gcc.dg/vect/no-scevccp-outer-2.c: Expect to vectorize.
+	* gcc.dg/vect/vect-double-reduc-1.c, gcc.dg/vect/vect-double-reduc-2.c,
+	gcc.dg/vect/vect-double-reduc-3.c, gcc.dg/vect/vect-double-reduc-4.c,
+	gcc.dg/vect/vect-double-reduc-5.c, gcc.dg/vect/vect-double-reduc-6.c,
+	gcc.dg/vect/vect-double-reduc-7.c: New tests.
+
 2009-07-12  Hans-Peter Nilsson  <hp@axis.com>
 
 	* gfortran.dg/f2003_io_4.f03, gfortran.dg/read_size_noadvance.f90,

gcc/testsuite/gcc.dg/vect/no-scevccp-outer-2.c

 /* { dg-do compile } */
+/* { dg-require-effective-target vect_int } */
+
 #define N 40
 
 int
@@ -14,5 +16,5 @@ foo (){
   return diff;
 }
 
-/* { dg-final { scan-tree-dump-times "OUTER LOOP VECTORIZED" 1 "vect" { xfail *-*-* } } } */
+/* { dg-final { scan-tree-dump-times "OUTER LOOP VECTORIZED" 1 "vect"  } } */
 /* { dg-final { cleanup-tree-dump "vect" } } */

gcc/testsuite/gcc.dg/vect/vect-double-reduc-1.c

+/* { dg-require-effective-target vect_int_mult } */
+
+#include <stdarg.h>
+#include <stdio.h>
+#include "tree-vect.h"
+
+#define K 32
+
+int in[2*K][K] __attribute__ ((__aligned__(__BIGGEST_ALIGNMENT__)));
+int coeff[K][K] __attribute__ ((__aligned__(__BIGGEST_ALIGNMENT__)));
+int out[K];
+int check_result[K] = {642816,660736,678656,696576,714496,732416,750336,768256,786176,804096,822016,839936,857856,875776,893696,911616,929536,947456,965376,983296,1001216,1019136,1037056,1054976,1072896,1090816,1108736,1126656,1144576,1162496,1180416,1198336};
+
+__attribute__ ((noinline)) void 
+foo ()
+{
+  int sum = 0, i, j, k;
+
+  for (k = 0; k < K; k++)
+    {
+      sum = 0;
+      for (j = 0; j < K; j++) 
+        for (i = 0; i < K; i++) 
+          sum += in[i+k][j] * coeff[i][j];
+ 
+      out[k] = sum;
+    }
+}
+
+int main ()
+{
+  int i, j, k;
+
+  check_vect ();
+
+  for  (j = 0; j < K; j++)
+    {
+      for (i = 0; i < 2*K; i++)
+        in[i][j] = i+j;
+
+      for (i = 0; i < K; i++)
+        coeff[i][j] = i+2;
+    }
+
+  foo();
+
+  for (k = 0; k < K; k++)
+    if (out[k] != check_result[k])
+      abort ();
+
+  return 0;
+}
+        
+/* { dg-final { scan-tree-dump-times "OUTER LOOP VECTORIZED" 1 "vect" } } */
+/* { dg-final { cleanup-tree-dump "vect" } } */
+      

gcc/testsuite/gcc.dg/vect/vect-double-reduc-2.c

+/* { dg-require-effective-target vect_int_mult } */
+
+#include <stdarg.h>
+#include <stdio.h>
+#include "tree-vect.h"
+
+#define K 32
+
+int in[2*K][K] __attribute__ ((__aligned__(__BIGGEST_ALIGNMENT__)));
+int coeff[K][K] __attribute__ ((__aligned__(__BIGGEST_ALIGNMENT__)));
+int out[K];
+int check_result[K] = {357184,339264,321344,303424,285504,267584,249664,231744,213824,195904,177984,160064,142144,124224,106304,88384,70464,52544,34624,16704,-1216,-19136,-37056,-54976,-72896,-90816,-108736,-126656,-144576,-162496,-180416,-198336};
+
+__attribute__ ((noinline)) void 
+foo ()
+{
+  int res = 0, i, j, k;
+
+  for (k = 0; k < K; k++)
+    {
+      res = 1000000;
+      for (j = 0; j < K; j++) 
+        for (i = 0; i < K; i++) 
+          res -= in[i+k][j] * coeff[i][j];
+ 
+      out[k] = res;
+    }
+}
+
+int main ()
+{
+  int i, j, k;
+
+  check_vect ();
+
+  for  (j = 0; j < K; j++)
+    {
+      for (i = 0; i < 2*K; i++)
+        in[i][j] = i+j;
+
+      for (i = 0; i < K; i++)
+        coeff[i][j] = i+2;
+    }
+
+  foo();
+
+  for (k = 0; k < K; k++)
+    if (out[k] != check_result[k])
+      abort ();
+
+  return 0;
+}
+        
+/* { dg-final { scan-tree-dump-times "OUTER LOOP VECTORIZED" 1 "vect" } } */
+/* { dg-final { cleanup-tree-dump "vect" } } */
+      

gcc/testsuite/gcc.dg/vect/vect-double-reduc-3.c

+/* { dg-require-effective-target vect_int } */
+
+#include <stdarg.h>
+#include <stdio.h>
+#include "tree-vect.h"
+
+#define K 32
+
+int in[2*K][K] __attribute__ ((__aligned__(__BIGGEST_ALIGNMENT__)));
+int coeff[K][K] __attribute__ ((__aligned__(__BIGGEST_ALIGNMENT__)));
+int out_max[K], out_min[K];
+int check_max[K] = {62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93};
+int check_min[K] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31};
+
+__attribute__ ((noinline)) void 
+foo (int x, int y)
+{
+  int max, min, i, j, k;
+
+  for (k = 0; k < K; k++)
+    {
+      max = x;
+      min = y;
+      for (j = 0; j < K; j++) 
+        for (i = 0; i < K; i++)
+          {
+            max = max < in[i+k][j] ? in[i+k][j] : max; 
+            min = min > in[i+k][j] ? in[i+k][j] : min; 
+          }
+      out_max[k] = max;
+      out_min[k] = min;
+    }
+}
+
+int main ()
+{
+  int i, j, k;
+
+  check_vect ();
+
+  for  (j = 0; j < K; j++)
+    {
+      for (i = 0; i < 2*K; i++)
+        in[i][j] = i+j;
+
+      for (i = 0; i < K; i++)
+        coeff[i][j] = i+2;
+    }
+
+  foo(0, 0);
+
+  for (k = 0; k < K; k++)
+    if (out_max[k] != check_max[k] || out_min[k] != 0)
+      abort ();
+
+  foo(100, 45);
+
+  for (k = 0; k < K; k++)
+    if (out_min[k] != check_min[k] || out_max[k] != 100)
+      abort ();
+
+  return 0;
+}
+        
+/* { dg-final { scan-tree-dump-times "OUTER LOOP VECTORIZED" 1 "vect" { xfail vect_no_int_max } } } */
+/* { dg-final { cleanup-tree-dump "vect" } } */
+      

gcc/testsuite/gcc.dg/vect/vect-double-reduc-4.c

+/* { dg-require-effective-target vect_int_mult } */
+
+#include <stdarg.h>
+#include <stdio.h>
+#include "tree-vect.h"
+
+#define K 32
+
+int in[2*K][K] __attribute__ ((__aligned__(__BIGGEST_ALIGNMENT__)));
+int coeff[K][K] __attribute__ ((__aligned__(__BIGGEST_ALIGNMENT__)));
+int out[K];
+int check_result[K] = {652816,670736,688656,706576,724496,742416,760336,778256,796176,814096,832016,849936,867856,885776,903696,921616,939536,957456,975376,993296,1011216,1029136,1047056,1064976,1082896,1100816,1118736,1136656,1154576,1172496,1190416,1208336};
+
+__attribute__ ((noinline)) void 
+foo ()
+{
+  int sum = 0, i, j, k;
+
+  for (k = 0; k < K; k++)
+    {
+      sum = 10000;
+      for (j = 0; j < K; j++) 
+        for (i = 0; i < K; i++) 
+          sum += in[i+k][j] * coeff[i][j];
+ 
+      out[k] = sum;
+    }
+}
+
+int main ()
+{
+  int i, j, k;
+
+  check_vect ();
+
+  for  (j = 0; j < K; j++)
+    {
+      for (i = 0; i < 2*K; i++)
+        in[i][j] = i+j;
+
+      for (i = 0; i < K; i++)
+        coeff[i][j] = i+2;
+    }
+
+  foo();
+
+  for (k = 0; k < K; k++)
+    if (out[k] != check_result[k])
+      abort ();
+
+  return 0;
+}
+        
+/* { dg-final { scan-tree-dump-times "OUTER LOOP VECTORIZED" 1 "vect" } } */
+/* { dg-final { cleanup-tree-dump "vect" } } */
+      

gcc/testsuite/gcc.dg/vect/vect-double-reduc-5.c

+/* { dg-require-effective-target vect_int_mult } */
+
+#include <stdarg.h>
+#include <stdio.h>
+#include "tree-vect.h"
+
+#define K 32
+
+signed short in[2*K][K] __attribute__ ((__aligned__(__BIGGEST_ALIGNMENT__)));
+signed short coeff[K][K] __attribute__ ((__aligned__(__BIGGEST_ALIGNMENT__)));
+int out[K];
+int check_result[K] = {642816,660736,678656,696576,714496,732416,750336,768256,786176,804096,822016,839936,857856,875776,893696,911616,929536,947456,965376,983296,1001216,1019136,1037056,1054976,1072896,1090816,1108736,1126656,1144576,1162496,1180416,1198336};
+
+__attribute__ ((noinline)) void 
+foo ()
+{
+  int sum = 0, i, j, k;
+
+  for (k = 0; k < K; k++)
+    {
+      sum = 0;
+      for (j = 0; j < K; j++) 
+        for (i = 0; i < K; i++) 
+          sum += in[i+k][j] * coeff[i][j];
+ 
+      out[k] = sum;
+    }
+}
+
+int main ()
+{
+  int i, j, k;
+
+  check_vect ();
+
+  for  (j = 0; j < K; j++)
+    {
+      for (i = 0; i < 2*K; i++)
+        in[i][j] = i+j;
+
+      for (i = 0; i < K; i++)
+        coeff[i][j] = i+2;
+    }
+
+  foo();
+
+  for (k = 0; k < K; k++)
+    if (out[k] != check_result[k])
+      abort ();
+
+  return 0;
+}
+
+/* Vectorization of loops with multiple types and double reduction is not 
+   supported yet.  */       
+/* { dg-final { scan-tree-dump-times "OUTER LOOP VECTORIZED" 1 "vect" { xfail *-*-* } } } */
+/* { dg-final { cleanup-tree-dump "vect" } } */
+      

gcc/testsuite/gcc.dg/vect/vect-double-reduc-6.c

+/* { dg-require-effective-target vect_int_mult } */
+
+#include <stdarg.h>
+#include <stdio.h>
+#include "tree-vect.h"
+
+#define K 4 
+
+int in[2*K][K] __attribute__ ((__aligned__(__BIGGEST_ALIGNMENT__)));
+int out[K];
+int check_result[K] = {0,16,256,4096};
+
+__attribute__ ((noinline)) void 
+foo ()
+{
+  int sum;
+  int i, j, k;
+
+  for (k = 0; k < K; k++)
+    {
+      sum = 1;
+      for (j = 0; j < K; j++) 
+        for (i = 0; i < K; i++)
+          sum *= in[i+k][j];
+      out[k] = sum;
+    }
+}
+
+int main ()
+{
+  int i, j, k;
+
+  check_vect ();
+
+  for (i = 0; i < 2*K; i++)
+    for (j = 0; j < K; j++)
+      in[i][j] = (i+2)/3;
+
+  foo();
+
+  for (k = 0; k < K; k++)
+    if (out[k] != check_result[k])
+      abort ();
+
+  return 0;
+}
+        
+/* { dg-final { scan-tree-dump-times "OUTER LOOP VECTORIZED" 1 "vect" } } */
+/* { dg-final { cleanup-tree-dump "vect" } } */
+      

gcc/testsuite/gcc.dg/vect/vect-double-reduc-7.c

+/* { dg-require-effective-target vect_int } */
+
+#include <stdarg.h>
+#include <stdio.h>
+#include "tree-vect.h"
+
+#define K 32
+
+int in[2*K][K] __attribute__ ((__aligned__(__BIGGEST_ALIGNMENT__)));
+int out[K];
+int check_result[K] = {63,63,191,191,127,127,191,191,127,127,191,191,127,127,191,191,127,127,191,191,127,127,191,191,127,127,191,191,127,127,191,191};
+
+__attribute__ ((noinline)) void 
+foo ()
+{
+  int res_or, res_and, res_xor, i, j, k;
+
+  for (k = 0; k < K; k++)
+    {
+      res_or = 0;
+      for (j = 0; j < K; j++) 
+        for (i = 0; i < K; i++) 
+          res_or = res_or | in[i+k][j];
+ 
+      res_and = 1;
+      for (j = 0; j < K; j++)
+        for (i = 0; i < K; i++)
+          res_and = res_and & in[i+k][j];
+
+      res_xor = 0;
+      for (j = 0; j < K; j++)
+        for (i = 0; i < K; i++)
+          res_xor = res_xor ^ in[i+k][j];
+
+      out[k] = res_or + res_and + res_xor;
+    }
+}
+
+int main ()
+{
+  int i, j, k;
+
+  check_vect ();
+
+  for  (j = 0; j < K; j++)
+    {
+      for (i = 0; i < 2*K; i++)
+        in[i][j] = i+j;
+
+      for (i = 0; i < K; i++)
+        out[i] = i+j;
+    }
+
+  foo();
+
+  for (k = 0; k < K; k++)
+    if (out[k] != check_result[k])
+      abort ();
+
+  return 0;
+}
+        
+/* { dg-final { scan-tree-dump-times "OUTER LOOP VECTORIZED" 3 "vect" } } */
+/* { dg-final { cleanup-tree-dump "vect" } } */
+      

gcc/tree-parloops.c

@@ -284,13 +284,15 @@ loop_parallel_p (struct loop *loop, htab_t reduction_list,
     {
       gimple phi = gsi_stmt (gsi);
       gimple reduc_stmt = NULL;
+      bool dummy;
 
       /* ??? TODO: Change this into a generic function that 
          recognizes reductions.  */
       if (!is_gimple_reg (PHI_RESULT (phi)))
 	continue;
       if (simple_loop_info)
-	reduc_stmt = vect_is_simple_reduction (simple_loop_info, phi, true);
+	reduc_stmt = vect_is_simple_reduction (simple_loop_info, phi, true, 
+                                               &dummy);
 
       /*  Create a reduction_info struct, initialize it and insert it to 
          the reduction list.  */

gcc/tree-vect-stmts.c

@@ -331,7 +331,7 @@ process_use (gimple stmt, tree use, loop_vec_info loop_vinfo, bool live_p,
 		...
 	inner-loop:
 		d = def_stmt
-	outer-loop-tail-bb:
+	outer-loop-tail-bb (or outer-loop-exit-bb in double reduction):
 		stmt # use (d)		*/
   else if (flow_loop_nested_p (bb->loop_father, def_bb->loop_father))
     {
@@ -341,7 +341,8 @@ process_use (gimple stmt, tree use, loop_vec_info loop_vinfo, bool live_p,
       switch (relevant)
         {
         case vect_unused_in_scope:
-          relevant = (STMT_VINFO_DEF_TYPE (stmt_vinfo) == vect_reduction_def) ?
+          relevant = (STMT_VINFO_DEF_TYPE (stmt_vinfo) == vect_reduction_def 
+            || STMT_VINFO_DEF_TYPE (stmt_vinfo) == vect_double_reduction_def) ?
                       vect_used_in_outer_by_reduction : vect_unused_in_scope;
           break;
 
@@ -393,7 +394,8 @@ vect_mark_stmts_to_be_vectorized (loop_vec_info loop_vinfo)
   basic_block bb;
   gimple phi;
   bool live_p;
-  enum vect_relevant relevant;
+  enum vect_relevant relevant, tmp_relevant;
+  enum vect_def_type def_type;
 
   if (vect_print_dump_info (REPORT_DETAILS))
     fprintf (vect_dump, "=== vect_mark_stmts_to_be_vectorized ===");
@@ -465,49 +467,64 @@ vect_mark_stmts_to_be_vectorized (loop_vec_info loop_vinfo)
 	 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.  */
 
-      if (STMT_VINFO_DEF_TYPE (stmt_vinfo) == vect_reduction_def)
+      def_type = STMT_VINFO_DEF_TYPE (stmt_vinfo);
+      tmp_relevant = relevant;
+      switch (def_type)
         {
-	  enum vect_relevant tmp_relevant = relevant;
-	  switch (tmp_relevant)
-	    {
-	    case vect_unused_in_scope:
-	      gcc_assert (gimple_code (stmt) != GIMPLE_PHI);
-	      relevant = vect_used_by_reduction;
-	      break;
+          case vect_reduction_def:
+	    switch (tmp_relevant)
+	      {
+	        case vect_unused_in_scope:
+	          relevant = vect_used_by_reduction;
+	          break;
 
-	    case vect_used_by_reduction:
-	      if (gimple_code (stmt) == GIMPLE_PHI)
-		break;
-	      /* fall through */
+	        case vect_used_by_reduction:
+	          if (gimple_code (stmt) == GIMPLE_PHI)
+                    break;
+  	          /* fall through */
 
-	    default:
-	      if (vect_print_dump_info (REPORT_DETAILS))
-	        fprintf (vect_dump, "unsupported use of reduction.");
-	      VEC_free (gimple, heap, worklist);
-	      return false;
-	    }
+	        default:
+	          if (vect_print_dump_info (REPORT_DETAILS))
+	            fprintf (vect_dump, "unsupported use of reduction.");
 
-	  live_p = false;	
-	}
-      else if (STMT_VINFO_DEF_TYPE (stmt_vinfo) == vect_nested_cycle)
-        {
-          enum vect_relevant tmp_relevant = relevant;
-          switch (tmp_relevant)
-            {
-              case vect_unused_in_scope:
-              case vect_used_in_outer_by_reduction:
-              case vect_used_in_outer:
-                break;
+  	          VEC_free (gimple, heap, worklist);
+	          return false;
+	      }
 
-              default:
+	    live_p = false;	
+	    break;
+ 
+          case vect_nested_cycle:
+            if (tmp_relevant != vect_unused_in_scope
+                && tmp_relevant != vect_used_in_outer_by_reduction
+                && tmp_relevant != vect_used_in_outer)
+              {
                 if (vect_print_dump_info (REPORT_DETAILS))
                   fprintf (vect_dump, "unsupported use of nested cycle.");
 
                 VEC_free (gimple, heap, worklist);
                 return false;
-            }
+              }
+
+            live_p = false; 
+            break; 
+      
+          case vect_double_reduction_def:
+            if (tmp_relevant != vect_unused_in_scope
+                && tmp_relevant != vect_used_by_reduction)
+              {
+                if (vect_print_dump_info (REPORT_DETAILS))
+                  fprintf (vect_dump, "unsupported use of double reduction.");
+
+                VEC_free (gimple, heap, worklist);
+                return false;
+              }
+
+            live_p = false;
+            break; 
 
-          live_p = false; 
+          default:
+            break;
         }
  
       FOR_EACH_PHI_OR_STMT_USE (use_p, stmt, iter, SSA_OP_USE)
@@ -974,6 +991,7 @@ vect_get_vec_def_for_operand (tree op, gimple stmt, tree *scalar_def)
 
     /* Case 4: operand is defined by a loop header phi - reduction  */
     case vect_reduction_def:
+    case vect_double_reduction_def:
     case vect_nested_cycle:
       {
 	struct loop *loop;

gcc/tree-vectorizer.h

@@ -61,6 +61,7 @@ enum vect_def_type {
   vect_internal_def,
   vect_induction_def,
   vect_reduction_def,
+  vect_double_reduction_def,
   vect_nested_cycle,
   vect_unknown_def_type
 };
@@ -822,7 +823,7 @@ extern tree vect_create_addr_base_for_vector_ref (gimple, gimple_seq *,
 /* In tree-vect-loop.c.  */
 /* FORNOW: Used in tree-parloops.c.  */
 extern void destroy_loop_vec_info (loop_vec_info, bool);
-extern gimple vect_is_simple_reduction (loop_vec_info, gimple, bool);
+extern gimple vect_is_simple_reduction (loop_vec_info, gimple, bool, bool *);
 /* Drive for loop analysis stage.  */
 extern loop_vec_info vect_analyze_loop (struct loop *);
 /* Drive for loop transformation stage.  */