freedreno: clear vs scissor

The optimization of avoiding restore (mem2gmem) if there was a clear
falls down a bit if you don't have a fullscreen scissor.  We need to
make the decision logic a bit more clever to keep track of *what* was
cleared, so that we can (a) completely skip mem2gmem if entire buffer
was cleared, or (b) skip mem2gmem on a per-tile basis for tiles that
were completely cleared.

Signed-off-by: Rob Clark <robclark@freedesktop.org>

1 files changed, 13 insertions, 1 deletions

diff --git a/src/gallium/drivers/freedreno/freedreno_context.h b/src/gallium/drivers/freedreno/freedreno_context.h
index be2c2638a1..22d950c090 100644
--- a/src/gallium/drivers/freedreno/freedreno_context.h
+++ b/src/gallium/drivers/freedreno/freedreno_context.h
@@ -182,6 +182,10 @@ struct fd_context {
 	 * there was a glClear() that invalidated the entire previous buffer
 	 * contents.  Keep track of which buffer(s) are cleared, or needs
 	 * restore.  Masks of PIPE_CLEAR_*
+	 *
+	 * The 'cleared' bits will be set for buffers which are *entirely*
+	 * cleared, and 'partial_cleared' bits will be set if you must
+	 * check cleared_scissor.
 	 */
 	enum {
 		/* align bitmask values w/ PIPE_CLEAR_*.. since that is convenient.. */
@@ -189,7 +193,7 @@ struct fd_context {
 		FD_BUFFER_DEPTH   = PIPE_CLEAR_DEPTH,
 		FD_BUFFER_STENCIL = PIPE_CLEAR_STENCIL,
 		FD_BUFFER_ALL     = FD_BUFFER_COLOR | FD_BUFFER_DEPTH | FD_BUFFER_STENCIL,
-	} cleared, restore, resolve;
+	} cleared, partial_cleared, restore, resolve;
 
 	bool needs_flush;
 
@@ -276,6 +280,14 @@ struct fd_context {
 	 */
 	struct pipe_scissor_state max_scissor;
 
+	/* Track the cleared scissor for color/depth/stencil, so we know
+	 * which, if any, tiles need to be restored (mem2gmem).  Only valid
+	 * if the corresponding bit in ctx->cleared is set.
+	 */
+	struct {
+		struct pipe_scissor_state color, depth, stencil;
+	} cleared_scissor;
+
 	/* Current gmem/tiling configuration.. gets updated on render_tiles()
 	 * if out of date with current maximal-scissor/cpp:
 	 */