gallium: call tgsi_set_exec_mask() and use exec mask in SSE ARL code

This prevents vertex shaders from referencing invalid memory locations when
the shader is operating on less than four vertices or fragments.

1 files changed, 6 insertions, 0 deletions

diff --git a/src/gallium/auxiliary/draw/draw_vs_exec.c b/src/gallium/auxiliary/draw/draw_vs_exec.c
index 44563803f9..82d27d4493 100644
--- a/src/gallium/auxiliary/draw/draw_vs_exec.c
+++ b/src/gallium/auxiliary/draw/draw_vs_exec.c
@@ -120,6 +120,12 @@ vs_exec_run_linear( struct draw_vertex_shader *shader,
 	 input = (const float (*)[4])((const char *)input + input_stride);
       } 
 
+      tgsi_set_exec_mask(machine,
+                         1,
+                         max_vertices > 1,
+                         max_vertices > 2,
+                         max_vertices > 3);
+
       /* run interpreter */
       tgsi_exec_machine_run( machine );