[PULL 4/9] hw/display/artist: Avoid drawing line when nothing to display

[Richard Henderson]

From: Philippe Mathieu-Daudé <address@hidden>

Signed-off-by: Philippe Mathieu-Daudé <address@hidden>
Message-Id: <address@hidden>
Signed-off-by: Richard Henderson <address@hidden>
---
 hw/display/artist.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/hw/display/artist.c b/hw/display/artist.c
index 97c811b35e..5492079116 100644
--- a/hw/display/artist.c
+++ b/hw/display/artist.c
@@ -579,6 +579,9 @@ static void draw_line(ARTISTState *s, int x1, int y1, int 
x2, int y2,
     } else {
         dy = y1 - y2;
     }
+    if (!dx || !dy) {
+        return;
+    }
 
     c1 = false;
     if (dy > dx) {
-- 
2.20.1