* tree-vrp.c (finalize_jump_threads): Do not care about dominance info.

	(execute_vrp): Preserve loops through jump threading.
	* tree-ssa-threadupdate.c (thread_single_edge,
	dbds_continue_enumeration_p, determine_bb_domination_status,
	thread_through_loop_header): New functions.
	(create_edge_and_update_destination_phis,
	create_edge_and_update_destination_phis): Set loops for the new blocks.
	(prune_undesirable_thread_requests): Removed.
	(redirect_edges): Do not pretend that redirect_edge_and_branch can
	create new blocks.
	(thread_block): Do not call prune_undesirable_thread_requests.
	Update loops.
	(mark_threaded_blocks): Select edges to thread here.
	(thread_through_all_blocks): Take may_peel_loop_headers argument.
	Thread edges through loop headers independently.
	* cfgloopmanip.c (create_preheader, mfb_keep_just): Export.
	* tree-pass.h (TODO_mark_first_instance): New.
	(first_pass_instance): Declare.
	* cfghooks.c (duplicate_block): Put the block to the original loop
	if copy is not specified.
	* tree-ssa-dom.c (tree_ssa_dominator_optimize): Preserve loops through
	jump threading.  Pass may_peel_loop_headers to
	thread_through_all_blocks according to first_pass_instance.
	* cfgloop.h (create_preheader): Declare.
	* tree-flow.h (thread_through_all_blocks): Declaration changed.
	* basic-block.h (mfb_keep_just, mfb_kj_edge): Declare.
	* passes.c (first_pass_instance): New variable.
	(next_pass_1): Set TODO_mark_first_instance.
	(execute_todo): Set first_pass_instance.

	* gcc.dg/tree-ssa/ssa-dom-thread-2.c: New test.
	* gcc.dg/vect/vect-102.c, gcc.dg/vect/vect-103.c,
	gcc.dg/vect/vect-104.c: Use more complex construction to prevent vectorizing.
	* gcc.dg/tree-ssa/pr21559.c: Update outcome.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@124786 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 3 insertions, 4 deletions

diff --git a/gcc/cfgloopmanip.c b/gcc/cfgloopmanip.c
index 4c658df876b..1fadbb4356d 100644
--- a/gcc/cfgloopmanip.c
+++ b/gcc/cfgloopmanip.c
@@ -41,7 +41,6 @@ static int find_path (edge, basic_block **);
 static void fix_loop_placements (struct loop *, bool *);
 static bool fix_bb_placement (basic_block);
 static void fix_bb_placements (basic_block, bool *);
-static basic_block create_preheader (struct loop *, int);
 static void unloop (struct loop *, bool *);
 
 #define RDIV(X,Y) (((X) + (Y) / 2) / (Y))
@@ -1085,8 +1084,8 @@ duplicate_loop_to_header_edge (struct loop *loop, edge e,
    MFB_KJ_EDGE to the entry part.  E is the edge for that we should decide
    whether to redirect it.  */
 
-static edge mfb_kj_edge;
-static bool
+edge mfb_kj_edge;
+bool
 mfb_keep_just (edge e)
 {
   return e != mfb_kj_edge;
@@ -1097,7 +1096,7 @@ mfb_keep_just (edge e)
    entry; otherwise we also force preheader block to have only one successor.
    The function also updates dominators.  */
 
-static basic_block
+basic_block
 create_preheader (struct loop *loop, int flags)
 {
   edge e, fallthru;