From 2deff35ded578b095a945864858ce635d8357ddc Mon Sep 17 00:00:00 2001
From: Quentin Carbonneaux <quentin.carbonneaux@yale.edu>
Date: Tue, 10 Nov 2015 20:26:22 -0500
Subject: add a few safeguards

---
 lisc/ssa.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

(limited to 'lisc')

diff --git a/lisc/ssa.c b/lisc/ssa.c
index 455b687..d58ce85 100644
--- a/lisc/ssa.c
+++ b/lisc/ssa.c
@@ -105,8 +105,10 @@ inter(Blk *b1, Blk *b2)
 			b1 = b2;
 			b2 = bt;
 		}
-		while (b1->id > b2->id)
+		while (b1->id > b2->id) {
 			b1 = b1->idom;
+			assert(b1);
+		}
 	}
 	return b1;
 }
@@ -149,6 +151,7 @@ filldom(Fn *fn)
 static int
 sdom(Blk *b1, Blk *b2)
 {
+	assert(b1 && b2);
 	if (b1 == b2)
 		return 0;
 	while (b2->id > b1->id)
-- 
cgit 1.4.1