From: Matthias Braun <matze@braunis.de>
Date: Mon, 3 May 2010 09:10:44 +0000 (+0000)
Subject: use barriers instead of be_Keep to keep unused nodes since we can't guarantee the... 
X-Git-Url: http://nsz.repo.hu/git/?a=commitdiff_plain;h=4ebf91ab4349975628962fcae404cdf0c340f49e;p=libfirm

use barriers instead of be_Keep to keep unused nodes since we can't guarantee the rule that a keep is always right behind the definition of a value

[r27462]
---

diff --git a/ir/be/bepeephole.c b/ir/be/bepeephole.c
index c14faf82a..5d3065b0f 100644
--- a/ir/be/bepeephole.c
+++ b/ir/be/bepeephole.c
@@ -307,7 +307,8 @@ static void skip_barrier(ir_node *block, ir_graph *irg)
 				assert(n < n_in);
 				in[n++] = get_irn_n(irn, i);
 			}
-			keep = be_new_Keep(get_nodes_block(irn), n_in, in);
+			keep = be_new_Barrier(get_nodes_block(irn), n_in, in);
+			keep_alive(keep);
 			sched_add_before(irn, keep);
 		}
 
@@ -322,7 +323,7 @@ static void skip_barrier(ir_node *block, ir_graph *irg)
 static void	kill_barriers(ir_graph *irg)
 {
 	ir_node *end_blk = get_irg_end_block(irg);
-	ir_node *start_blk;
+	ir_node *start_blk = get_irg_start_block(irg);
 	int i;
 
 	/* skip the barrier on all return blocks */
@@ -330,6 +331,9 @@ static void	kill_barriers(ir_graph *irg)
 		ir_node *be_ret = get_Block_cfgpred(end_blk, i);
 		ir_node *ret_blk = get_nodes_block(be_ret);
 
+		if (ret_blk == start_blk)
+			continue;
+
 		skip_barrier(ret_blk, irg);
 	}