draw: don't try to precalculate the pipeline output primitive

We were previously calculating a value which was either the geometry
shader output primitive or the application's input primitive, and
passing that to the various front/middle/back components for use as
the ultimate rendering primtive.

Unfortunately, this was not correct -- if the vcache decomposition
path is active and geometry shaders are *not* active, we can end up
with a third primitive -- specifically the decomposed version of the
input primitive.

Rather than trying to precalculate this, just let the individual
components inform their successors about which primitive type they are
recieving.

8 files changed, 46 insertions, 34 deletions

diff --git a/src/gallium/auxiliary/draw/draw_pt.c b/src/gallium/auxiliary/draw/draw_pt.c
index 02c97fec817..6234272d6ce 100644
--- a/src/gallium/auxiliary/draw/draw_pt.c
+++ b/src/gallium/auxiliary/draw/draw_pt.c
@@ -69,7 +69,6 @@ draw_pt_arrays(struct draw_context *draw,
    struct draw_pt_front_end *frontend = NULL;
    struct draw_pt_middle_end *middle = NULL;
    unsigned opt = 0;
-   unsigned out_prim = prim;
 
    /* Sanitize primitive length:
     */
@@ -80,18 +79,19 @@ draw_pt_arrays(struct draw_context *draw,
       if (count < first)
          return TRUE;
    }
-   if (draw->gs.geometry_shader) {
-      out_prim = draw->gs.geometry_shader->output_primitive;
-   }
 
    if (!draw->force_passthrough) {
+      unsigned gs_out_prim = (draw->gs.geometry_shader ? 
+                              draw->gs.geometry_shader->output_primitive :
+                              prim);
+
       if (!draw->render) {
          opt |= PT_PIPELINE;
       }
 
       if (draw_need_pipeline(draw,
                              draw->rasterizer,
-                             out_prim)) {
+                             gs_out_prim)) {
          opt |= PT_PIPELINE;
       }
 
@@ -122,7 +122,7 @@ draw_pt_arrays(struct draw_context *draw,
       frontend = draw->pt.front.varray;
    }
 
-   frontend->prepare( frontend, prim, out_prim, middle, opt );
+   frontend->prepare( frontend, prim, middle, opt );
 
    frontend->run(frontend,
                  draw_pt_elt_func(draw),
diff --git a/src/gallium/auxiliary/draw/draw_pt.h b/src/gallium/auxiliary/draw/draw_pt.h
index b6741ca83ce..44356fba4c5 100644
--- a/src/gallium/auxiliary/draw/draw_pt.h
+++ b/src/gallium/auxiliary/draw/draw_pt.h
@@ -62,8 +62,7 @@ struct draw_vertex_info;
  */
 struct draw_pt_front_end {
    void (*prepare)( struct draw_pt_front_end *,
-                    unsigned input_prim,
-                    unsigned output_prim,
+                    unsigned prim,
                     struct draw_pt_middle_end *,
 		    unsigned opt );
 
@@ -87,8 +86,7 @@ struct draw_pt_front_end {
  */
 struct draw_pt_middle_end {
    void (*prepare)( struct draw_pt_middle_end *,
-                    unsigned input_prim,
-                    unsigned output_prim,
+                    unsigned prim,
 		    unsigned opt,
                     unsigned *max_vertices );
 
diff --git a/src/gallium/auxiliary/draw/draw_pt_fetch_emit.c b/src/gallium/auxiliary/draw/draw_pt_fetch_emit.c
index c629d555636..5c8af17c8e3 100644
--- a/src/gallium/auxiliary/draw/draw_pt_fetch_emit.c
+++ b/src/gallium/auxiliary/draw/draw_pt_fetch_emit.c
@@ -36,6 +36,7 @@
 #include "draw/draw_vbuf.h"
 #include "draw/draw_vertex.h"
 #include "draw/draw_pt.h"
+#include "draw/draw_gs.h"
 #include "translate/translate.h"
 #include "translate/translate_cache.h"
 
@@ -90,7 +91,6 @@ struct fetch_emit_middle_end {
 
 static void fetch_emit_prepare( struct draw_pt_middle_end *middle,
                                 unsigned prim,
-                                unsigned out_prim,
 				unsigned opt,
                                 unsigned *max_vertices )
 {
@@ -101,9 +101,14 @@ static void fetch_emit_prepare( struct draw_pt_middle_end *middle,
    boolean ok;
    struct translate_key key;
 
+   unsigned gs_out_prim = (draw->gs.geometry_shader ? 
+                           draw->gs.geometry_shader->output_primitive :
+                           prim);
+
+
 
    ok = draw->render->set_primitive( draw->render, 
-                                     out_prim );
+                                     gs_out_prim );
    if (!ok) {
       assert(0);
       return;
diff --git a/src/gallium/auxiliary/draw/draw_pt_fetch_shade_emit.c b/src/gallium/auxiliary/draw/draw_pt_fetch_shade_emit.c
index 5483a25f1dc..b8270280b64 100644
--- a/src/gallium/auxiliary/draw/draw_pt_fetch_shade_emit.c
+++ b/src/gallium/auxiliary/draw/draw_pt_fetch_shade_emit.c
@@ -68,8 +68,7 @@ struct fetch_shade_emit {
 
 
 static void fse_prepare( struct draw_pt_middle_end *middle,
-                         unsigned in_prim,
-                         unsigned out_prim,
+                         unsigned prim,
                          unsigned opt,
                          unsigned *max_vertices )
 {
@@ -80,9 +79,12 @@ static void fse_prepare( struct draw_pt_middle_end *middle,
    unsigned i;
    unsigned nr_vbs = 0;
 
+   /* Can't support geometry shader on this path.
+    */
+   assert(!draw->gs.geometry_shader);
 
    if (!draw->render->set_primitive( draw->render,
-                                     out_prim )) {
+                                     prim )) {
       assert(0);
       return;
    }
diff --git a/src/gallium/auxiliary/draw/draw_pt_fetch_shade_pipeline.c b/src/gallium/auxiliary/draw/draw_pt_fetch_shade_pipeline.c
index 43b08a030cf..047e192d4d1 100644
--- a/src/gallium/auxiliary/draw/draw_pt_fetch_shade_pipeline.c
+++ b/src/gallium/auxiliary/draw/draw_pt_fetch_shade_pipeline.c
@@ -48,13 +48,11 @@ struct fetch_pipeline_middle_end {
    unsigned vertex_data_offset;
    unsigned vertex_size;
    unsigned input_prim;
-   unsigned output_prim;
    unsigned opt;
 };
 
 static void fetch_pipeline_prepare( struct draw_pt_middle_end *middle,
-                                    unsigned in_prim,
-                                    unsigned out_prim,
+                                    unsigned prim,
 				    unsigned opt,
                                     unsigned *max_vertices )
 {
@@ -64,6 +62,10 @@ static void fetch_pipeline_prepare( struct draw_pt_middle_end *middle,
    unsigned i;
    unsigned instance_id_index = ~0;
 
+   unsigned gs_out_prim = (draw->gs.geometry_shader ? 
+                           draw->gs.geometry_shader->output_primitive :
+                           prim);
+
    /* Add one to num_outputs because the pipeline occasionally tags on
     * an additional texcoord, eg for AA lines.
     */
@@ -79,8 +81,7 @@ static void fetch_pipeline_prepare( struct draw_pt_middle_end *middle,
       }
    }
 
-   fpme->input_prim = in_prim;
-   fpme->output_prim = out_prim;
+   fpme->input_prim = prim;
    fpme->opt = opt;
 
    /* Always leave room for the vertex header whether we need it or
@@ -108,7 +109,7 @@ static void fetch_pipeline_prepare( struct draw_pt_middle_end *middle,
 
    if (!(opt & PT_PIPELINE)) {
       draw_pt_emit_prepare( fpme->emit,
-			    out_prim,
+			    gs_out_prim,
                             max_vertices );
 
       *max_vertices = MAX2( *max_vertices,
diff --git a/src/gallium/auxiliary/draw/draw_pt_fetch_shade_pipeline_llvm.c b/src/gallium/auxiliary/draw/draw_pt_fetch_shade_pipeline_llvm.c
index 7d2de58e733..774fb7bf7a2 100644
--- a/src/gallium/auxiliary/draw/draw_pt_fetch_shade_pipeline_llvm.c
+++ b/src/gallium/auxiliary/draw/draw_pt_fetch_shade_pipeline_llvm.c
@@ -49,7 +49,6 @@ struct llvm_middle_end {
    unsigned vertex_data_offset;
    unsigned vertex_size;
    unsigned input_prim;
-   unsigned output_prim;
    unsigned opt;
 
    struct draw_llvm *llvm;
@@ -62,7 +61,6 @@ struct llvm_middle_end {
 static void
 llvm_middle_end_prepare( struct draw_pt_middle_end *middle,
                          unsigned in_prim,
-                         unsigned out_prim,
                          unsigned opt,
                          unsigned *max_vertices )
 {
@@ -74,6 +72,11 @@ llvm_middle_end_prepare( struct draw_pt_middle_end *middle,
    unsigned i;
    unsigned instance_id_index = ~0;
 
+
+   unsigned out_prim = (draw->gs.geometry_shader ? 
+                        draw->gs.geometry_shader->output_primitive :
+                        in_prim);
+
    /* Add one to num_outputs because the pipeline occasionally tags on
     * an additional texcoord, eg for AA lines.
     */
@@ -90,7 +93,6 @@ llvm_middle_end_prepare( struct draw_pt_middle_end *middle,
    }
 
    fpme->input_prim = in_prim;
-   fpme->output_prim = out_prim;
    fpme->opt = opt;
 
    /* Always leave room for the vertex header whether we need it or
diff --git a/src/gallium/auxiliary/draw/draw_pt_varray.c b/src/gallium/auxiliary/draw/draw_pt_varray.c
index 5ea833032f3..d89d5cd20f4 100644
--- a/src/gallium/auxiliary/draw/draw_pt_varray.c
+++ b/src/gallium/auxiliary/draw/draw_pt_varray.c
@@ -137,7 +137,6 @@ static unsigned decompose_prim[PIPE_PRIM_POLYGON + 1] = {
 
 static void varray_prepare(struct draw_pt_front_end *frontend,
                            unsigned in_prim,
-                           unsigned out_prim,
                            struct draw_pt_middle_end *middle,
                            unsigned opt)
 {
@@ -146,11 +145,12 @@ static void varray_prepare(struct draw_pt_front_end *frontend,
    varray->base.run = varray_run;
 
    varray->input_prim = in_prim;
-   varray->output_prim = decompose_prim[out_prim];
+   varray->output_prim = decompose_prim[in_prim];
 
    varray->middle = middle;
-   middle->prepare(middle, varray->input_prim,
-                   varray->output_prim, opt, &varray->driver_fetch_max );
+   middle->prepare(middle,
+                   varray->output_prim,
+                   opt, &varray->driver_fetch_max );
 
    /* check that the max is even */
    assert((varray->driver_fetch_max & 1) == 0);
diff --git a/src/gallium/auxiliary/draw/draw_pt_vcache.c b/src/gallium/auxiliary/draw/draw_pt_vcache.c
index 914c87a9dc4..b7e0da7d44e 100644
--- a/src/gallium/auxiliary/draw/draw_pt_vcache.c
+++ b/src/gallium/auxiliary/draw/draw_pt_vcache.c
@@ -70,7 +70,6 @@ vcache_flush( struct vcache_frontend *vcache )
    if (vcache->middle_prim != vcache->output_prim) {
       vcache->middle_prim = vcache->output_prim;
       vcache->middle->prepare( vcache->middle,
-                               vcache->input_prim,
                                vcache->middle_prim,
                                vcache->opt,
                                &vcache->fetch_max );
@@ -368,7 +367,6 @@ vcache_check_run( struct draw_pt_front_end *frontend,
    if (vcache->middle_prim != vcache->input_prim) {
       vcache->middle_prim = vcache->input_prim;
       vcache->middle->prepare( vcache->middle,
-                               vcache->input_prim,
                                vcache->middle_prim,
                                vcache->opt,
                                &vcache->fetch_max );
@@ -472,7 +470,6 @@ vcache_check_run( struct draw_pt_front_end *frontend,
 static void
 vcache_prepare( struct draw_pt_front_end *frontend,
                 unsigned in_prim,
-                unsigned out_prim,
                 struct draw_pt_middle_end *middle,
                 unsigned opt )
 {
@@ -487,8 +484,14 @@ vcache_prepare( struct draw_pt_front_end *frontend,
       vcache->base.run = vcache_check_run;
    }
 
+   /* VCache will always emit the reduced version of its input
+    * primitive, ie STRIP/FANS become TRIS, etc.
+    *
+    * This is not to be confused with what the GS might be up to,
+    * which is a separate issue.
+    */
    vcache->input_prim = in_prim;
-   vcache->output_prim = u_reduced_prim(out_prim);
+   vcache->output_prim = u_reduced_prim(in_prim);
 
    vcache->middle = middle;
    vcache->opt = opt;
@@ -497,8 +500,9 @@ vcache_prepare( struct draw_pt_front_end *frontend,
     * doing so:
     */
    vcache->middle_prim = (opt & PT_PIPELINE) ? vcache->output_prim : vcache->input_prim;
-   middle->prepare( middle, vcache->input_prim,
-                    vcache->middle_prim, opt, &vcache->fetch_max );
+   middle->prepare( middle,
+                    vcache->middle_prim,
+                    opt, &vcache->fetch_max );
 }