[PATCH]middle-end: remove more usages of single_exit

[Tamar Christina]

Hi All,

This replaces two more usages of single_exit that I had missed before.
They both seem to happen when we re-use the ifcvt scalar loop for versioning.

The condition in versioning is the same as the one for when we don't re-use the
scalar loop.

I hit these during an LTO enabled bootstrap now.

Bootstrapped Regtested on aarch64-none-linux-gnu with lto enabled and no issues.

Ok for master?

Thanks,
Tamar

gcc/ChangeLog:

        * tree-vect-loop-manip.cc (vect_loop_versioning): Replace single_exit.
        * tree-vect-loop.cc (vect_transform_loop): Likewise.

--- inline copy of patch -- 
diff --git a/gcc/tree-vect-loop-manip.cc b/gcc/tree-vect-loop-manip.cc
index 
0931b18404856f6c33dcae1ffa8d5a350dbd0f8f..0d8c90f69e9693d5d25095e799fbc17a9910779b
 100644
--- a/gcc/tree-vect-loop-manip.cc
+++ b/gcc/tree-vect-loop-manip.cc
@@ -4051,7 +4051,16 @@ vect_loop_versioning (loop_vec_info loop_vinfo,
       basic_block preheader = loop_preheader_edge (loop_to_version)->src;
       preheader->count = preheader->count.apply_probability (prob * prob2);
       scale_loop_frequencies (loop_to_version, prob * prob2);
-      single_exit (loop_to_version)->dest->count = preheader->count;
+      /* When the loop has multiple exits then we can only version itself.
+       This is denoted by loop_to_version == loop.  In this case we can
+       do the versioning by selecting the exit edge the vectorizer is
+       currently using.  */
+      edge exit_edge;
+      if (loop_to_version == loop)
+       exit_edge = LOOP_VINFO_IV_EXIT (loop_vinfo);
+      else
+       exit_edge = single_exit (loop_to_version);
+      exit_edge->dest->count = preheader->count;
       LOOP_VINFO_SCALAR_LOOP_SCALING (loop_vinfo) = (prob * prob2).invert ();
 
       nloop = scalar_loop;
diff --git a/gcc/tree-vect-loop.cc b/gcc/tree-vect-loop.cc
index 
da2dfa176ecd457ebc11d1131302ca15d77d779d..eccf0953bbae2a0e95efba0966c85492e5057b14
 100644
--- a/gcc/tree-vect-loop.cc
+++ b/gcc/tree-vect-loop.cc
@@ -11910,8 +11910,7 @@ vect_transform_loop (loop_vec_info loop_vinfo, gimple 
*loop_vectorized_call)
              (LOOP_VINFO_SCALAR_LOOP_SCALING (loop_vinfo));
       scale_loop_frequencies (LOOP_VINFO_SCALAR_LOOP (loop_vinfo),
                              LOOP_VINFO_SCALAR_LOOP_SCALING (loop_vinfo));
-      single_exit (LOOP_VINFO_SCALAR_LOOP (loop_vinfo))->dest->count
-       = preheader->count;
+      LOOP_VINFO_SCALAR_IV_EXIT (loop_vinfo)->dest->count = preheader->count;
     }
 
   if (niters_vector == NULL_TREE)




-- 

diff --git a/gcc/tree-vect-loop-manip.cc b/gcc/tree-vect-loop-manip.cc
index 
0931b18404856f6c33dcae1ffa8d5a350dbd0f8f..0d8c90f69e9693d5d25095e799fbc17a9910779b
 100644
--- a/gcc/tree-vect-loop-manip.cc
+++ b/gcc/tree-vect-loop-manip.cc
@@ -4051,7 +4051,16 @@ vect_loop_versioning (loop_vec_info loop_vinfo,
       basic_block preheader = loop_preheader_edge (loop_to_version)->src;
       preheader->count = preheader->count.apply_probability (prob * prob2);
       scale_loop_frequencies (loop_to_version, prob * prob2);
-      single_exit (loop_to_version)->dest->count = preheader->count;
+      /* When the loop has multiple exits then we can only version itself.
+       This is denoted by loop_to_version == loop.  In this case we can
+       do the versioning by selecting the exit edge the vectorizer is
+       currently using.  */
+      edge exit_edge;
+      if (loop_to_version == loop)
+       exit_edge = LOOP_VINFO_IV_EXIT (loop_vinfo);
+      else
+       exit_edge = single_exit (loop_to_version);
+      exit_edge->dest->count = preheader->count;
       LOOP_VINFO_SCALAR_LOOP_SCALING (loop_vinfo) = (prob * prob2).invert ();
 
       nloop = scalar_loop;
diff --git a/gcc/tree-vect-loop.cc b/gcc/tree-vect-loop.cc
index 
da2dfa176ecd457ebc11d1131302ca15d77d779d..eccf0953bbae2a0e95efba0966c85492e5057b14
 100644
--- a/gcc/tree-vect-loop.cc
+++ b/gcc/tree-vect-loop.cc
@@ -11910,8 +11910,7 @@ vect_transform_loop (loop_vec_info loop_vinfo, gimple 
*loop_vectorized_call)
              (LOOP_VINFO_SCALAR_LOOP_SCALING (loop_vinfo));
       scale_loop_frequencies (LOOP_VINFO_SCALAR_LOOP (loop_vinfo),
                              LOOP_VINFO_SCALAR_LOOP_SCALING (loop_vinfo));
-      single_exit (LOOP_VINFO_SCALAR_LOOP (loop_vinfo))->dest->count
-       = preheader->count;
+      LOOP_VINFO_SCALAR_IV_EXIT (loop_vinfo)->dest->count = preheader->count;
     }
 
   if (niters_vector == NULL_TREE)