* loop-iv.c: New file.

	* Makefile.in (loop-iv.o): New.
	* basic_block.h (FOR_BB_INSNS, FOR_BB_INSNS_REVERSE): New macros.
	* cfgloop.c (fill_sons_in_loop, get_loop_body_in_dom_order,
	num_loop_branches): New functions.
	* cfgloop.h (get_loop_body_in_dom_order, num_loop_branches,
	iv_analysis_loop_init, iv_get_reaching_def, iv_analyse, get_iv_value,
	find_simple_exit, iv_number_of_iterations, iv_analysis_done,
	get_simple_loop_desc, free_simple_loop_desc): Declare.
	(simple_loop_desc): New inline function.
	(struct rtx_iv, struct niter_desc): New.
	* cfgloopmanip.c (loopify): Specify semantics more precisely.
	* expr.c (force_operand): Handle subregs of expressions created by
	loop unroller.
	* loop-init.c (loop_optimizer_init, loop_optimizer_finalize): Move
	parts of the initialization to toplev.c
	* loop-unroll.c (loop_exit_at_end_p): New.
	(unroll_and_peel_loops): Call iv_analysis_done.
	(decide_peel_once_rolling, decide_peel_completely,
	decide_unroll_stupid, decide_unroll_constant_iterations,
	decide_unroll_runtime_iterations, decide_peel_simple,
	peel_loop_simple, unroll_loop_stupid, unroll_loop_constant_iterations,
	unroll_loop_runtime_iterations): Use new simple loop analysis.
	* loop-unswitch.c (compare_and_jump_seq): New.
	(may_unswitch_on_p): Renamed to ...
	(may_unswitch_on): Use new iv analysis.
	(reversed_condition): Export.
	(unswitch_single_loop, unswitch_loop): Use new iv analysis.
	* predict.c (estimate_probability): Use new simple loop analysis.
	* rtl.h (get_mode_bounds, reversed_condition,compare_and_jump_seq,
	canon_condition, simplify_using_condition): Declare.
	* stor-layout.c (get_mode_bounds): New.
	* toplev.c (rest_of_handle_loop2): Some parts of
	initialization/finalization moved here from loop-init.c.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@77951 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 9 insertions, 5 deletions

diff --git a/gcc/cfgloopmanip.c b/gcc/cfgloopmanip.c
index 3b8bcec7b22..35444eea1c9 100644
--- a/gcc/cfgloopmanip.c
+++ b/gcc/cfgloopmanip.c
@@ -480,11 +480,13 @@ scale_loop_frequencies (struct loop *loop, int num, int den)
    accordingly. Everything between them plus LATCH_EDGE destination must
    be dominated by HEADER_EDGE destination, and back-reachable from
    LATCH_EDGE source.  HEADER_EDGE is redirected to basic block SWITCH_BB,
-   SWITCH_BB->succ to original destination of LATCH_EDGE and
-   SWITCH_BB->succ->succ_next to original destination of HEADER_EDGE.
+   FALLTHRU_EDGE (SWITCH_BB) to original destination of HEADER_EDGE and
+   BRANCH_EDGE (SWITCH_BB) to original destination of LATCH_EDGE.
    Returns newly created loop.  */
+
 struct loop *
-loopify (struct loops *loops, edge latch_edge, edge header_edge, basic_block switch_bb)
+loopify (struct loops *loops, edge latch_edge, edge header_edge, 
+	 basic_block switch_bb)
 {
   basic_block succ_bb = latch_edge->dest;
   basic_block pred_bb = header_edge->src;
@@ -509,13 +511,15 @@ loopify (struct loops *loops, edge latch_edge, edge header_edge, basic_block swi
 
   /* Redirect edges.  */
   loop_redirect_edge (latch_edge, loop->header);
+  loop_redirect_edge (BRANCH_EDGE (switch_bb), succ_bb);
+
   loop_redirect_edge (header_edge, switch_bb);
-  loop_redirect_edge (switch_bb->succ->succ_next, loop->header);
-  loop_redirect_edge (switch_bb->succ, succ_bb);
+  loop_redirect_edge (FALLTHRU_EDGE (switch_bb), loop->header); 
 
   /* Update dominators.  */
   set_immediate_dominator (CDI_DOMINATORS, switch_bb, pred_bb);
   set_immediate_dominator (CDI_DOMINATORS, loop->header, switch_bb);
+
   set_immediate_dominator (CDI_DOMINATORS, succ_bb, switch_bb);
 
   /* Compute new loop.  */