i965/gs: Move generation check for bailing earlier.

On Sandybridge, we don't need to break down primitives.  There's no need
to bother setting up brw_compile and such if it's not going to be used;
bail as early as possible.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Eric Anholt <eric@anholt.net>

src/mesa/drivers/dri/i965/brw_gs.c

@@ -52,6 +52,12 @@ static void compile_gs_prog( struct brw_context *brw,
    const GLuint *program;
    GLuint program_size;
 
+   /* Gen6: VF has already converted into polygon, and LINELOOP is
+    * converted to LINESTRIP at the beginning of the 3D pipeline.
+    */
+   if (intel->gen == 6)
+      return;
+
    memset(&c, 0, sizeof(c));
    
    c.key = *key;
@@ -84,12 +90,6 @@ static void compile_gs_prog( struct brw_context *brw,
     * already been weeded out by this stage:
     */
 
-   /* Gen6: VF has already converted into polygon, and LINELOOP is
-    * converted to LINESTRIP at the beginning of the 3D pipeline.
-    */
-   if (intel->gen == 6)
-      return;
-
    switch (key->primitive) {
    case GL_QUADS:
       brw_gs_quads( &c, key );