i965: Introduce a brw_vue_prog_data::include_vue_handles flag.

Tessellation shaders and SIMD8 geometry shaders may need to resort to
the pull model for inputs at times.  When set, the state upload code
will tell the hardware to provide URB handles for input data.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Kristian Høgsberg <krh@bitplanet.net>

src/mesa/drivers/dri/i965/brw_compiler.h

@@ -485,6 +485,9 @@ struct brw_vue_prog_data {
    struct brw_stage_prog_data base;
    struct brw_vue_map vue_map;
 
+   /** Should the hardware deliver input VUE handles for URB pull loads? */
+   bool include_vue_handles;
+
    GLuint urb_read_length;
    GLuint total_grf;
 

src/mesa/drivers/dri/i965/gen8_gs_state.c

@@ -68,6 +68,8 @@ gen8_upload_gs_state(struct brw_context *brw)
                  GEN7_GS_OUTPUT_VERTEX_SIZE_SHIFT) |
                 (brw->gs.prog_data->output_topology <<
                  GEN7_GS_OUTPUT_TOPOLOGY_SHIFT) |
+                (prog_data->include_vue_handles ?
+                 GEN7_GS_INCLUDE_VERTEX_HANDLES : 0) |
                 (prog_data->urb_read_length <<
                  GEN6_GS_URB_READ_LENGTH_SHIFT) |
                 (0 << GEN6_GS_URB_ENTRY_READ_OFFSET_SHIFT) |