jump.c (reset_insn_reg_label_operand_notes): New function, split out from ...

	* jump.c (reset_insn_reg_label_operand_notes): New function,
	split out from ...
	(init_label_info): ... here.  Reset LABEL_NUSES in cfglayout mode.
	* cfgcleanup.c (delete_dead_jump_tables_between): New function,
	split out from ...
	(delete_dead_jumptables): ... here.  Handle cfglayout mode.
	(cleanup_cfg): Delete dead jump tables in cfglayout mode if an
	expensive CFG cleanup is called for.
	* cfgrtl.c (fixup_reorder_chain): Remove BARRIERs from fallthru paths.
	(cfg_layout_finalize): Delete dead jump tables before re-building
	the insns chain.
	* ira.c (ira): Rebuild jump labels *after* deleting unreachable
	basic blocks, not before.
	* loop-init.c (rtl_loop_done): Call for an expensive CFG cleanup.

	* modulo-sched.c (sms_schedule): Do not look for BARRIERs in the
	insns chain of a scheduling extended basic block, they cannot appear
	there in cfglayout mode.

From-SVN: r205337

1 files changed, 21 insertions, 10 deletions

diff --git a/gcc/cfgrtl.c b/gcc/cfgrtl.c
index 63f44af..4ce7273 100644
--- a/gcc/cfgrtl.c
+++ b/gcc/cfgrtl.c
@@ -3696,10 +3696,10 @@ fixup_reorder_chain (void)
 #endif
 
   /* Now add jumps and labels as needed to match the blocks new
-     outgoing edges.  */
+     outgoing edges.  Fixup missing or redundant BARRIERs.  */
 
-  for (bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb; bb ; bb = (basic_block)
-       bb->aux)
+  for (bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb; bb ;
+       bb = (basic_block) bb->aux)
     {
       edge e_fall, e_taken, e;
       rtx bb_end_insn;
@@ -3853,13 +3853,26 @@ fixup_reorder_chain (void)
 
   relink_block_chain (/*stay_in_cfglayout_mode=*/false);
 
-  /* Annoying special case - jump around dead jumptables left in the code.  */
+  /* Annoying special case - stray barriers left in the code.  This happens
+     if a tablejump is transformed to a simpe or confitional jump, or if a
+     basic block ending in a tablejump is removed but the jump table itself
+     is not.  */
   FOR_EACH_BB (bb)
     {
       edge e = find_fallthru_edge (bb->succs);
 
-      if (e && !can_fallthru (e->src, e->dest))
-	force_nonfallthru (e);
+      if (e && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun))
+	{
+	  rtx insn, next;
+	  for (insn = NEXT_INSN (BB_END (e->src));
+	       insn != BB_HEAD (e->dest);
+	       insn = next)
+	    {
+	      next = NEXT_INSN (insn);
+	      if (BARRIER_P (insn))
+		remove_insn (insn);
+	    }
+	}
     }
 
   /* Ensure goto_locus from edges has some instructions with that locus
@@ -4273,7 +4286,7 @@ break_superblocks (void)
 }
 
 /* Finalize the changes: reorder insn list according to the sequence specified
-   by aux pointers, enter compensation code, rebuild scope forest.  */
+   by aux pointers, enter compensation code.  */
 
 void
 cfg_layout_finalize (void)
@@ -4281,6 +4294,7 @@ cfg_layout_finalize (void)
 #ifdef ENABLE_CHECKING
   verify_flow_info ();
 #endif
+  delete_dead_jumptables ();
   force_one_exit_fallthru ();
   rtl_register_cfg_hooks ();
   if (reload_completed
@@ -4291,9 +4305,6 @@ cfg_layout_finalize (void)
     fixup_fallthru_exit_predecessor ();
   fixup_reorder_chain ();
 
-  rebuild_jump_labels (get_insns ());
-  delete_dead_jumptables ();
-
 #ifdef ENABLE_CHECKING
   verify_insn_chain ();
   verify_flow_info ();