llvmpipe: use single swizzled tile

Use a single swizzled tile per colorbuf (and per thread) to avoid
accumulating large amounts of cached swizzled data.

Now that the SSE3 code has been merged to master, the performance delta
of this change is minimal, the main benefit is reduced memory usage
due to no longer keeping swizzled copies of render targets.

It's clear from the performance of the in-place version of this code
that there is still quite a bit of time being spent swizzling &
unswizzling, but it's not clear exactly how to reduce that.

1 files changed, 10 insertions, 14 deletions

diff --git a/src/gallium/drivers/llvmpipe/lp_rast_priv.h b/src/gallium/drivers/llvmpipe/lp_rast_priv.h
index 8044927c8b..b4a48cfd02 100644
--- a/src/gallium/drivers/llvmpipe/lp_rast_priv.h
+++ b/src/gallium/drivers/llvmpipe/lp_rast_priv.h
@@ -148,7 +148,7 @@ lp_rast_get_depth_block_pointer(struct lp_rasterizer_task *task,
        * the oom warning as this most likely because there is no
        * zsbuf.
        */
-      return lp_get_dummy_tile_silent();
+      return lp_dummy_tile;
    }
 
    depth = (rast->zsbuf.map +
@@ -178,15 +178,14 @@ lp_rast_get_color_tile_pointer(struct lp_rasterizer_task *task,
       struct llvmpipe_resource *lpt;
       assert(cbuf);
       lpt = llvmpipe_resource(cbuf->texture);
-      task->color_tiles[buf] = llvmpipe_get_texture_tile(lpt,
-                                                         cbuf->face + cbuf->zslice,
-                                                         cbuf->level,
-                                                         usage,
-                                                         task->x,
-                                                         task->y);
-      if (!task->color_tiles[buf]) {
-         /* out of memory - use dummy tile memory */
-         return lp_get_dummy_tile();
+      task->color_tiles[buf] = lp_swizzled_cbuf[task->thread_index][buf];
+
+      if (usage != LP_TEX_USAGE_WRITE_ALL) {
+         llvmpipe_swizzle_cbuf_tile(lpt,
+                                    cbuf->face + cbuf->zslice,
+                                    cbuf->level,
+                                    task->x, task->y,
+                                    task->color_tiles[buf]);
       }
    }
 
@@ -212,10 +211,7 @@ lp_rast_get_color_block_pointer(struct lp_rasterizer_task *task,
    assert((y % TILE_VECTOR_HEIGHT) == 0);
 
    color = lp_rast_get_color_tile_pointer(task, buf, LP_TEX_USAGE_READ_WRITE);
-   if (!color) {
-      /* out of memory - use dummy tile memory */
-      return lp_get_dummy_tile();
-   }
+   assert(color);
 
    px = x % TILE_SIZE;
    py = y % TILE_SIZE;