PR rtl-optimization/48235

	* sel-sched.c (code_motion_process_successors): Recompute the last
	insn in basic block if control flow changed.
	(code_motion_path_driver): Ditto.  Recompute the first insn as well.
	Update condition for ilist_remove.

testsuite:
	* gcc.dg/pr48235.c: New.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@172177 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 22 insertions, 3 deletions

diff --git a/gcc/sel-sched.c b/gcc/sel-sched.c
index 48fb2e0134d..f409c4fa2cc 100644
--- a/gcc/sel-sched.c
+++ b/gcc/sel-sched.c
@@ -6369,7 +6369,10 @@ code_motion_process_successors (insn_t insn, av_set_t orig_ops,
          the iterator becomes invalid.  We need to try again.  */
       if (BLOCK_FOR_INSN (insn)->index != old_index
           || EDGE_COUNT (bb->succs) != old_succs)
-        goto rescan;
+        {
+          insn = sel_bb_end (BLOCK_FOR_INSN (insn));
+          goto rescan;
+        }
     }
 
 #ifdef ENABLE_CHECKING
@@ -6587,21 +6590,37 @@ code_motion_path_driver (insn_t insn, av_set_t orig_ops, ilist_t path,
   if (!expr)
     {
       int res;
+      rtx last_insn = PREV_INSN (insn);
+      bool added_to_path;
 
       gcc_assert (insn == sel_bb_end (bb));
 
       /* Add bb tail to PATH (but it doesn't make any sense if it's a bb_head -
 	 it's already in PATH then).  */
       if (insn != first_insn)
-	ilist_add (&path, insn);
+	{
+	  ilist_add (&path, insn);
+	  added_to_path = true;
+	}
+      else
+        added_to_path = false;
 
       /* Process_successors should be able to find at least one
 	 successor for which code_motion_path_driver returns TRUE.  */
       res = code_motion_process_successors (insn, orig_ops,
                                             path, static_params);
 
+      /* Jump in the end of basic block could have been removed or replaced
+         during code_motion_process_successors, so recompute insn as the
+         last insn in bb.  */
+      if (NEXT_INSN (last_insn) != insn)
+        {
+          insn = sel_bb_end (bb);
+          first_insn = sel_bb_head (bb);
+        }
+
       /* Remove bb tail from path.  */
-      if (insn != first_insn)
+      if (added_to_path)
 	ilist_remove (&path);
 
       if (res != 1)