svga: implement an index buffer translation cache

Some OpenGL apps, like Cinebench R15, have many glDrawElements(GL_QUADS)
calls.  Since we don't directly support quads we have to convert these
calls into GL_TRIANGLES which involves generating a new index buffer.

This patch saves the new/translated index buffer in the hope that it
can be reused for a later draw call.

Cinebench R15 increases by about 20% with this change.
The NobelClinician Viewer app also hits this code.
Tested with full piglit run.

Reviewed-by: Charmaine Lee <[email protected]>

1 files changed, 1 insertions, 0 deletions

diff --git a/src/gallium/drivers/svga/svga_screen.h b/src/gallium/drivers/svga/svga_screen.h
index 98b56b2a6d1..6cafeba1480 100644
--- a/src/gallium/drivers/svga/svga_screen.h
+++ b/src/gallium/drivers/svga/svga_screen.h
@@ -62,6 +62,7 @@ struct svga_screen
       boolean no_surface_view;
       boolean force_sampler_view;
       boolean no_sampler_view;
+      boolean no_cache_index_buffers;
    } debug;
 
    unsigned texture_timestamp;