[PATCH][1/n] Reduction vectorization improvements

[Richard Biener <rguenther at suse dot de>]

I'm at the moment tearing apart a large patch that adds support for
vectorizing reductions in basic-blocks as well as making loop
vectorizing reduction chains with patterns work.

This is a first piece - allow the reduction patterns be detected
when reduction detection didn't run and remove an assert in favor
of a check.

Bootstrap and regtest running on x86_64-unknown-linux-gnu.

Richard.

2015-05-21  Richard Biener  <rguenther@suse.de>

	* tree-vect-patterns.c (vect_recog_dot_prod_pattern): Replace
	assert with guard, remove check on detected reduction.
	(vect_recog_sad_pattern): Likewise.
	(vect_recog_widen_sum_pattern): Likewise.

Index: gcc/tree-vect-patterns.c
===================================================================
--- gcc/tree-vect-patterns.c	(revision 223470)
+++ gcc/tree-vect-patterns.c	(working copy)
@@ -318,6 +318,11 @@ vect_recog_dot_prod_pattern (vec<gimple>
 
   loop = LOOP_VINFO_LOOP (loop_info);
 
+  /* We don't allow changing the order of the computation in the inner-loop
+     when doing outer-loop vectorization.  */
+  if (loop && nested_in_vect_loop_p (loop, last_stmt))
+    return NULL;
+
   if (!is_gimple_assign (last_stmt))
     return NULL;
 
@@ -366,8 +371,6 @@ vect_recog_dot_prod_pattern (vec<gimple>
     {
       gimple def_stmt;
 
-      if (STMT_VINFO_DEF_TYPE (stmt_vinfo) != vect_reduction_def)
-        return NULL;
       oprnd0 = gimple_assign_rhs1 (last_stmt);
       oprnd1 = gimple_assign_rhs2 (last_stmt);
       if (!types_compatible_p (TREE_TYPE (oprnd0), type)
@@ -469,10 +472,6 @@ vect_recog_dot_prod_pattern (vec<gimple>
       dump_printf (MSG_NOTE, "\n");
     }
 
-  /* We don't allow changing the order of the computation in the inner-loop
-     when doing outer-loop vectorization.  */
-  gcc_assert (!nested_in_vect_loop_p (loop, last_stmt));
-
   return pattern_stmt;
 }
 
@@ -533,6 +532,11 @@ vect_recog_sad_pattern (vec<gimple> *stm
 
   loop = LOOP_VINFO_LOOP (loop_info);
 
+  /* We don't allow changing the order of the computation in the inner-loop
+     when doing outer-loop vectorization.  */
+  if (loop && nested_in_vect_loop_p (loop, last_stmt))
+    return NULL;
+
   if (!is_gimple_assign (last_stmt))
     return NULL;
 
@@ -586,8 +590,6 @@ vect_recog_sad_pattern (vec<gimple> *stm
     {
       gimple def_stmt;
 
-      if (STMT_VINFO_DEF_TYPE (stmt_vinfo) != vect_reduction_def)
-        return NULL;
       plus_oprnd0 = gimple_assign_rhs1 (last_stmt);
       plus_oprnd1 = gimple_assign_rhs2 (last_stmt);
       if (!types_compatible_p (TREE_TYPE (plus_oprnd0), sum_type)
@@ -703,10 +705,6 @@ vect_recog_sad_pattern (vec<gimple> *stm
       dump_printf (MSG_NOTE, "\n");
     }
 
-  /* We don't allow changing the order of the computation in the inner-loop
-     when doing outer-loop vectorization.  */
-  gcc_assert (!nested_in_vect_loop_p (loop, last_stmt));
-
   return pattern_stmt;
 }
 
@@ -1201,6 +1199,11 @@ vect_recog_widen_sum_pattern (vec<gimple
 
   loop = LOOP_VINFO_LOOP (loop_info);
 
+  /* We don't allow changing the order of the computation in the inner-loop
+     when doing outer-loop vectorization.  */
+  if (loop && nested_in_vect_loop_p (loop, last_stmt))
+    return NULL;
+
   if (!is_gimple_assign (last_stmt))
     return NULL;
 
@@ -1219,9 +1222,6 @@ vect_recog_widen_sum_pattern (vec<gimple
   if (gimple_assign_rhs_code (last_stmt) != PLUS_EXPR)
     return NULL;
 
-  if (STMT_VINFO_DEF_TYPE (stmt_vinfo) != vect_reduction_def)
-    return NULL;
-
   oprnd0 = gimple_assign_rhs1 (last_stmt);
   oprnd1 = gimple_assign_rhs2 (last_stmt);
   if (!types_compatible_p (TREE_TYPE (oprnd0), type)
@@ -1255,10 +1255,6 @@ vect_recog_widen_sum_pattern (vec<gimple
       dump_printf (MSG_NOTE, "\n");
     }
 
-  /* We don't allow changing the order of the computation in the inner-loop
-     when doing outer-loop vectorization.  */
-  gcc_assert (!nested_in_vect_loop_p (loop, last_stmt));
-
   return pattern_stmt;
 }