[gcc(refs/users/kubaneko/heads/histogram)] hubicka bug fix

[gcc(refs/users/kubaneko/heads/histogram)] hubicka bug fix

[Ondrej Kubanek]

https://gcc.gnu.org/g:1525af68c65e3f184397d9943ca3dce60ad5e18e

commit 1525af68c65e3f184397d9943ca3dce60ad5e18e
Author: kubaneko <kubanek0ondrej@gmail.com>
Date:   Fri Apr 21 15:34:54 2023 +0000

    hubicka bug fix

Diff:
---
 gcc/tree-ssa-loop-ch.cc | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/gcc/tree-ssa-loop-ch.cc b/gcc/tree-ssa-loop-ch.cc
index 6b332719411..e621011fe44 100644
--- a/gcc/tree-ssa-loop-ch.cc
+++ b/gcc/tree-ssa-loop-ch.cc
@@ -557,6 +557,17 @@ ch_base::copy_headers (function *fun)
 	    }
 	}
 
+      /* Update header of the loop.  */
+      loop->header = header;
+      /* Find correct latch.  We only duplicate chain of conditionals so
+         there should be precisely two edges to the new header.  One entry
+         edge and one to latch.  */
+      FOR_EACH_EDGE (e, ei, loop->header->preds)
+       if (header != e->src)
+         {
+           loop->latch = e->src;
+           break;
+         }
       /* Ensure that the latch and the preheader is simple (we know that they
 	 are not now, since there was the loop exit condition.  */
       split_edge (loop_preheader_edge (loop));
@@ -583,6 +594,8 @@ ch_base::copy_headers (function *fun)
 
   if (changed)
     {
+      if (flag_checking)
+       verify_loop_structure ();
       update_ssa (TODO_update_ssa);
       /* After updating SSA form perform CSE on the loop header
 	 copies.  This is esp. required for the pass before