gallium: add start_slot parameter to set_vertex_buffers

This allows updating only a subrange of buffer bindings.

set_vertex_buffers(pipe, start_slot, count, NULL) unbinds buffers in that
range. Binding NULL resources unbinds buffers too (both buffer and user_buffer
must be NULL).

The meta ops are adapted to only save, change, and restore the single slot
they use. The cso_context can save and restore only one vertex buffer slot.
The clients can query which one it is using cso_get_aux_vertex_buffer_slot.
It's currently set to 0. (the Draw module breaks if it's set to non-zero)

It should decrease the CPU overhead when using a lot of meta ops, but
the drivers must be able to treat each vertex buffer slot as a separate
state (only r600g does so at the moment).

I can imagine this also being useful for optimizing some OpenGL use cases.

Reviewed-by: Brian Paul <[email protected]>

8 files changed, 32 insertions, 15 deletions

diff --git a/src/mesa/state_tracker/st_atom_array.c b/src/mesa/state_tracker/st_atom_array.c
index ab46f11887e..c96f6dc70c3 100644
--- a/src/mesa/state_tracker/st_atom_array.c
+++ b/src/mesa/state_tracker/st_atom_array.c
@@ -574,7 +574,13 @@ static void update_array(struct st_context *st)
       num_velements = vpv->num_inputs;
    }
 
-   cso_set_vertex_buffers(st->cso_context, num_vbuffers, vbuffer);
+   cso_set_vertex_buffers(st->cso_context, 0, num_vbuffers, vbuffer);
+   if (st->last_num_vbuffers > num_vbuffers) {
+      /* Unbind remaining buffers, if any. */
+      cso_set_vertex_buffers(st->cso_context, num_vbuffers,
+                             st->last_num_vbuffers - num_vbuffers, NULL);
+   }
+   st->last_num_vbuffers = num_vbuffers;
    cso_set_vertex_elements(st->cso_context, num_velements, velements);
 }
 
diff --git a/src/mesa/state_tracker/st_cb_bitmap.c b/src/mesa/state_tracker/st_cb_bitmap.c
index b024ef0db32..843dc5be337 100644
--- a/src/mesa/state_tracker/st_cb_bitmap.c
+++ b/src/mesa/state_tracker/st_cb_bitmap.c
@@ -457,7 +457,7 @@ draw_bitmap_quad(struct gl_context *ctx, GLint x, GLint y, GLfloat z,
    cso_save_vertex_shader(cso);
    cso_save_geometry_shader(cso);
    cso_save_vertex_elements(cso);
-   cso_save_vertex_buffers(cso);
+   cso_save_aux_vertex_buffer_slot(cso);
 
    /* rasterizer state: just scissor */
    st->bitmap.rasterizer.scissor = ctx->Scissor.Enabled;
@@ -526,7 +526,9 @@ draw_bitmap_quad(struct gl_context *ctx, GLint x, GLint y, GLfloat z,
 			    x, y, width, height, z, color, &vbuf, &offset);
 
    if (vbuf) {
-      util_draw_vertex_buffer(pipe, st->cso_context, vbuf, offset,
+      util_draw_vertex_buffer(pipe, st->cso_context, vbuf,
+                              cso_get_aux_vertex_buffer_slot(st->cso_context),
+                              offset,
                               PIPE_PRIM_TRIANGLE_FAN,
                               4,  /* verts */
                               3); /* attribs/vert */
@@ -541,7 +543,7 @@ draw_bitmap_quad(struct gl_context *ctx, GLint x, GLint y, GLfloat z,
    cso_restore_vertex_shader(cso);
    cso_restore_geometry_shader(cso);
    cso_restore_vertex_elements(cso);
-   cso_restore_vertex_buffers(cso);
+   cso_restore_aux_vertex_buffer_slot(cso);
    cso_restore_stream_outputs(cso);
 
    pipe_resource_reference(&vbuf, NULL);
diff --git a/src/mesa/state_tracker/st_cb_clear.c b/src/mesa/state_tracker/st_cb_clear.c
index 90eb0af4fe0..4aa0bc18ff5 100644
--- a/src/mesa/state_tracker/st_cb_clear.c
+++ b/src/mesa/state_tracker/st_cb_clear.c
@@ -176,7 +176,9 @@ draw_quad(struct st_context *st,
    /* draw */
    util_draw_vertex_buffer(pipe,
                            st->cso_context,
-                           vbuf, offset,
+                           vbuf,
+                           cso_get_aux_vertex_buffer_slot(st->cso_context),
+                           offset,
                            PIPE_PRIM_TRIANGLE_FAN,
                            4,  /* verts */
                            2); /* attribs/vert */
@@ -225,7 +227,7 @@ clear_with_quad(struct gl_context *ctx,
    cso_save_vertex_shader(st->cso_context);
    cso_save_geometry_shader(st->cso_context);
    cso_save_vertex_elements(st->cso_context);
-   cso_save_vertex_buffers(st->cso_context);
+   cso_save_aux_vertex_buffer_slot(st->cso_context);
 
    /* blend state: RGBA masking */
    {
@@ -325,7 +327,7 @@ clear_with_quad(struct gl_context *ctx,
    cso_restore_vertex_shader(st->cso_context);
    cso_restore_geometry_shader(st->cso_context);
    cso_restore_vertex_elements(st->cso_context);
-   cso_restore_vertex_buffers(st->cso_context);
+   cso_restore_aux_vertex_buffer_slot(st->cso_context);
    cso_restore_stream_outputs(st->cso_context);
 }
 
diff --git a/src/mesa/state_tracker/st_cb_drawpixels.c b/src/mesa/state_tracker/st_cb_drawpixels.c
index 642011488cd..ff8a9dc4364 100644
--- a/src/mesa/state_tracker/st_cb_drawpixels.c
+++ b/src/mesa/state_tracker/st_cb_drawpixels.c
@@ -637,7 +637,9 @@ draw_quad(struct gl_context *ctx, GLfloat x0, GLfloat y0, GLfloat z,
    }
 
    u_upload_unmap(st->uploader);
-   util_draw_vertex_buffer(pipe, st->cso_context, buf, offset,
+   util_draw_vertex_buffer(pipe, st->cso_context, buf,
+                           cso_get_aux_vertex_buffer_slot(st->cso_context),
+                           offset,
 			   PIPE_PRIM_QUADS,
 			   4,  /* verts */
 			   3); /* attribs/vert */
@@ -683,7 +685,7 @@ draw_textured_quad(struct gl_context *ctx, GLint x, GLint y, GLfloat z,
    cso_save_vertex_shader(cso);
    cso_save_geometry_shader(cso);
    cso_save_vertex_elements(cso);
-   cso_save_vertex_buffers(cso);
+   cso_save_aux_vertex_buffer_slot(cso);
    if (write_stencil) {
       cso_save_depth_stencil_alpha(cso);
       cso_save_blend(cso);
@@ -808,7 +810,7 @@ draw_textured_quad(struct gl_context *ctx, GLint x, GLint y, GLfloat z,
    cso_restore_vertex_shader(cso);
    cso_restore_geometry_shader(cso);
    cso_restore_vertex_elements(cso);
-   cso_restore_vertex_buffers(cso);
+   cso_restore_aux_vertex_buffer_slot(cso);
    cso_restore_stream_outputs(cso);
    if (write_stencil) {
       cso_restore_depth_stencil_alpha(cso);
diff --git a/src/mesa/state_tracker/st_cb_drawtex.c b/src/mesa/state_tracker/st_cb_drawtex.c
index e87de44063e..269068da2b0 100644
--- a/src/mesa/state_tracker/st_cb_drawtex.c
+++ b/src/mesa/state_tracker/st_cb_drawtex.c
@@ -228,7 +228,7 @@ st_DrawTex(struct gl_context *ctx, GLfloat x, GLfloat y, GLfloat z,
    cso_save_vertex_shader(cso);
    cso_save_geometry_shader(cso);
    cso_save_vertex_elements(cso);
-   cso_save_vertex_buffers(cso);
+   cso_save_aux_vertex_buffer_slot(cso);
 
    {
       void *vs = lookup_shader(pipe, numAttribs,
@@ -266,6 +266,7 @@ st_DrawTex(struct gl_context *ctx, GLfloat x, GLfloat y, GLfloat z,
 
 
    util_draw_vertex_buffer(pipe, cso, vbuffer,
+			   cso_get_aux_vertex_buffer_slot(cso),
                            offset,  /* offset */
                            PIPE_PRIM_TRIANGLE_FAN,
                            4,  /* verts */
@@ -279,7 +280,7 @@ st_DrawTex(struct gl_context *ctx, GLfloat x, GLfloat y, GLfloat z,
    cso_restore_vertex_shader(cso);
    cso_restore_geometry_shader(cso);
    cso_restore_vertex_elements(cso);
-   cso_restore_vertex_buffers(cso);
+   cso_restore_aux_vertex_buffer_slot(cso);
    cso_restore_stream_outputs(cso);
 }
 
diff --git a/src/mesa/state_tracker/st_context.c b/src/mesa/state_tracker/st_context.c
index da361d88795..69bd50336ec 100644
--- a/src/mesa/state_tracker/st_context.c
+++ b/src/mesa/state_tracker/st_context.c
@@ -173,7 +173,8 @@ st_create_context_priv( struct gl_context *ctx, struct pipe_context *pipe,
       memset(&st->velems_util_draw[i], 0, sizeof(struct pipe_vertex_element));
       st->velems_util_draw[i].src_offset = i * 4 * sizeof(float);
       st->velems_util_draw[i].instance_divisor = 0;
-      st->velems_util_draw[i].vertex_buffer_index = 0;
+      st->velems_util_draw[i].vertex_buffer_index =
+            cso_get_aux_vertex_buffer_slot(st->cso_context);
       st->velems_util_draw[i].src_format = PIPE_FORMAT_R32G32B32A32_FLOAT;
    }
 
diff --git a/src/mesa/state_tracker/st_context.h b/src/mesa/state_tracker/st_context.h
index c85d09cb5cd..2cc52773efb 100644
--- a/src/mesa/state_tracker/st_context.h
+++ b/src/mesa/state_tracker/st_context.h
@@ -188,6 +188,9 @@ struct st_context
    int force_msaa;
    void *winsys_drawable_handle;
 
+   /* The number of vertex buffers from the last call of validate_arrays. */
+   unsigned last_num_vbuffers;
+
    /* Active render condition. */
    struct pipe_query *render_condition;
    unsigned condition_mode;
diff --git a/src/mesa/state_tracker/st_draw_feedback.c b/src/mesa/state_tracker/st_draw_feedback.c
index a6c7d0eec85..ae87fb28dbf 100644
--- a/src/mesa/state_tracker/st_draw_feedback.c
+++ b/src/mesa/state_tracker/st_draw_feedback.c
@@ -205,7 +205,7 @@ st_feedback_draw_vbo(struct gl_context *ctx,
 #endif
    }
 
-   draw_set_vertex_buffers(draw, vp->num_inputs, vbuffers);
+   draw_set_vertex_buffers(draw, 0, vp->num_inputs, vbuffers);
    draw_set_vertex_elements(draw, vp->num_inputs, velements);
 
    memset(&ibuffer, 0, sizeof(ibuffer));
@@ -264,5 +264,5 @@ st_feedback_draw_vbo(struct gl_context *ctx,
       draw_set_mapped_vertex_buffer(draw, attr, NULL);
       pipe_resource_reference(&vbuffers[attr].buffer, NULL);
    }
-   draw_set_vertex_buffers(draw, 0, NULL);
+   draw_set_vertex_buffers(draw, 0, vp->num_inputs, NULL);
 }