[PATCH] glamor: don't do render ops with matching source/dest (v2)

[Dave Airlie]

From: Dave Airlie <airlied at redhat.com>

XRender defines this, GL really doesn't like it.

kwin 4.x and qt 4.x seem to make this happen for the
gradient in the titlebar, and on radeonsi/r600 hw
this draws all kinds of wrong.

v2: bump this up a level, and check it earlier.
(I assume the XXXX was for this case.)

Signed-off-by: Dave Airlie <airlied at redhat.com>
---
 glamor/glamor_render.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/glamor/glamor_render.c b/glamor/glamor_render.c
index efca367..05eee91 100644
--- a/glamor/glamor_render.c
+++ b/glamor/glamor_render.c
@@ -1481,7 +1481,14 @@ glamor_composite_clipped_region(CARD8 op,
         }
     }
 
-    /*XXXXX, self copy? */
+    if (temp_src_pixmap == dest_pixmap) {
+        glamor_fallback("source and dest pixmaps are the same\n");
+        goto out;
+    }
+    if (temp_mask_pixmap == dest_pixmap) {
+        glamor_fallback("mask and dest pixmaps are the same\n");
+        goto out;
+    }
 
     x_dest += dest->pDrawable->x;
     y_dest += dest->pDrawable->y;
-- 
1.8.3.1