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]>

1 files changed, 0 insertions, 28 deletions

diff --git a/src/gallium/auxiliary/util/u_inlines.h b/src/gallium/auxiliary/util/u_inlines.h
index 5c6e7eb3234..3d68cf5400e 100644
--- a/src/gallium/auxiliary/util/u_inlines.h
+++ b/src/gallium/auxiliary/util/u_inlines.h
@@ -449,34 +449,6 @@ static INLINE boolean util_get_offset(
    }
 }
 
-/**
- * This function is used to copy an array of pipe_vertex_buffer structures,
- * while properly referencing the pipe_vertex_buffer::buffer member.
- *
- * \sa util_copy_framebuffer_state
- */
-static INLINE void util_copy_vertex_buffers(struct pipe_vertex_buffer *dst,
-                                            unsigned *dst_count,
-                                            const struct pipe_vertex_buffer *src,
-                                            unsigned src_count)
-{
-   unsigned i;
-
-   /* Reference the buffers of 'src' in 'dst'. */
-   for (i = 0; i < src_count; i++) {
-      pipe_resource_reference(&dst[i].buffer, src[i].buffer);
-   }
-   /* Unreference the rest of the buffers in 'dst'. */
-   for (; i < *dst_count; i++) {
-      pipe_resource_reference(&dst[i].buffer, NULL);
-   }
-
-   /* Update the size of 'dst' and copy over the other members
-    * of pipe_vertex_buffer. */
-   *dst_count = src_count;
-   memcpy(dst, src, src_count * sizeof(struct pipe_vertex_buffer));
-}
-
 static INLINE float
 util_get_min_point_size(const struct pipe_rasterizer_state *state)
 {