From: Andreas Zwinkau <zwinkau@kit.edu>
Date: Thu, 5 May 2011 08:15:19 +0000 (+0200)
Subject: fix opt/gcse_no_end
X-Git-Url: http://nsz.repo.hu/git/?a=commitdiff_plain;h=0a0b836f87b882bea34ef0f66ada10765e581837;p=libfirm

fix opt/gcse_no_end

jump threading must also copy Keep edges to keep End reachable.
---

diff --git a/ir/opt/jumpthreading.c b/ir/opt/jumpthreading.c
index 0f519a964..39e07dbe9 100644
--- a/ir/opt/jumpthreading.c
+++ b/ir/opt/jumpthreading.c
@@ -275,6 +275,13 @@ static void copy_and_fix(const jumpthreading_env_t *env, ir_node *block,
 		ir_node *copy;
 		ir_mode *mode;
 
+		if (is_End(node)) {
+			/* edge is a Keep edge. If the end block is unreachable via normal control flow,
+			 * we must maintain end's reachability with Keeps.
+			 */
+			keep_alive(copy_block);
+			continue;
+		}
 		/* ignore control flow */
 		mode = get_irn_mode(node);
 		if (mode == mode_X || is_Cond(node))