* cfgloopmanip.c (loop_delete_branch_edge): Removed.

	(remove_path): Use can_remove_branch_p and remove_branch instead
	of loop_delete_branch_edge.
	* tree-ssa-loop-manip.c (scale_dominated_blocks_in_loop): New function.
	(tree_transform_and_unroll_loop): Remove dead branches immediately.
	Update profile using scale_dominated_blocks_in_loop.
	* cfghooks.c (can_remove_branch_p, remove_branch): New functions.
	* cfghooks.h (struct cfg_hooks): Add can_remove_branch_p.
	(can_remove_branch_p, remove_branch): Declare.
	* tree-cfg.c (tree_can_remove_branch_p): New function.
	(tree_cfg_hooks): Add tree_can_remove_branch_p.
	* cfgrtl.c (rtl_can_remove_branch_p): New function.
	(rtl_cfg_hooks, cfg_layout_rtl_cfg_hook): Add rtl_can_remove_branch_p.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@121583 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 42 insertions, 0 deletions

diff --git a/gcc/cfghooks.c b/gcc/cfghooks.c
index d6a981d1db8..d65cce98fa9 100644
--- a/gcc/cfghooks.c
+++ b/gcc/cfghooks.c
@@ -318,6 +318,48 @@ redirect_edge_and_branch (edge e, basic_block dest)
   return ret;
 }
 
+/* Returns true if it is possible to remove the edge E by redirecting it
+   to the destination of the other edge going from its source.  */
+
+bool
+can_remove_branch_p (edge e)
+{
+  if (!cfg_hooks->can_remove_branch_p)
+    internal_error ("%s does not support can_remove_branch_p",
+		    cfg_hooks->name);
+
+  if (EDGE_COUNT (e->src->succs) != 2)
+    return false;
+
+  return cfg_hooks->can_remove_branch_p (e);
+}
+
+/* Removes E, by redirecting it to the destination of the other edge going
+   from its source.  Can_remove_branch_p must be true for E, hence this
+   operation cannot fail.  */
+
+void
+remove_branch (edge e)
+{
+  edge other;
+  basic_block src = e->src;
+  int irr;
+
+  gcc_assert (EDGE_COUNT (e->src->succs) == 2);
+
+  other = EDGE_SUCC (src, EDGE_SUCC (src, 0) == e);
+  irr = other->flags & EDGE_IRREDUCIBLE_LOOP;
+
+  if (current_loops != NULL)
+    rescan_loop_exit (e, false, true);
+
+  e = redirect_edge_and_branch (e, other->dest);
+  gcc_assert (e != NULL);
+
+  e->flags &= ~EDGE_IRREDUCIBLE_LOOP;
+  e->flags |= irr;
+}
+
 /* Redirect the edge E to basic block DEST even if it requires creating
    of a new basic block; then it returns the newly created basic block.
    Aborts when redirection is impossible.  */