cfglayout.c (fixup_reorder_chain): Postpone deleting dead jump tables...

	* cfglayout.c (fixup_reorder_chain): Postpone deleting dead
	jump tables, move the call to delete_dead_jumptables from here...
	(cfg_layout_finalize): ...to here.  But rebuild jump labels first.
	* cfgrtl.c (cfg_layout_can_merge_blocks_p): When not optimizing,
	don't allow merging of blocks that try_redirect_by_replacing_jump
	also does not handle when not optimizing.

From-SVN: r122957

gcc/ChangeLog

+2007-03-15  Steven Bosscher  <steven@gcc.gnu.org>
+
+	PR middle-end/31159
+	* cfglayout.c (fixup_reorder_chain): Postpone deleting dead
+	jump tables, move the call to delete_dead_jumptables from here...
+	(cfg_layout_finalize): ...to here.  But rebuild jump labels first.
+	* cfgrtl.c (cfg_layout_can_merge_blocks_p): When not optimizing,
+	don't allow merging of blocks that try_redirect_by_replacing_jump
+	also does not handle when not optimizing.
+
 2007-03-15  Uros Bizjak  <ubizjak@gmail.com>
 	    Francois-Xavier Coudert  <coudert@clipper.ens.fr>
 

gcc/cfglayout.c

@@ -697,7 +697,6 @@ fixup_reorder_chain (void)
 #ifdef ENABLE_CHECKING
   verify_insn_chain ();
 #endif
-  delete_dead_jumptables ();
 
   /* Now add jumps and labels as needed to match the blocks new
      outgoing edges.  */
@@ -1193,6 +1192,9 @@ 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 ();
 #endif

gcc/cfgrtl.c

@@ -2519,10 +2519,11 @@ cfg_layout_can_merge_blocks_p (basic_block a, basic_block b)
 	  /* Must be simple edge.  */
 	  && !(single_succ_edge (a)->flags & EDGE_COMPLEX)
 	  && a != ENTRY_BLOCK_PTR && b != EXIT_BLOCK_PTR
-	  /* If the jump insn has side effects,
-	     we can't kill the edge.  */
+	  /* If the jump insn has side effects, we can't kill the edge.
+	     When not optimizing, try_redirect_by_replacing_jump will
+	     not allow us to redirect an edge by replacing a table jump.  */
 	  && (!JUMP_P (BB_END (a))
-	      || (reload_completed
+	      || ((!optimize || reload_completed)
 		  ? simplejump_p (BB_END (a)) : onlyjump_p (BB_END (a)))));
 }