radeonsi: add compute_last_block to configure the partial block fields

1 files changed, 22 insertions, 0 deletions

diff --git a/src/gallium/drivers/radeonsi/si_pipe.h b/src/gallium/drivers/radeonsi/si_pipe.h
index 89a93182ed3..37eb15f539e 100644
--- a/src/gallium/drivers/radeonsi/si_pipe.h
+++ b/src/gallium/drivers/radeonsi/si_pipe.h
@@ -896,6 +896,28 @@ struct si_context {
 	uint32_t			vs_blit_sh_data[SI_VS_BLIT_SGPRS_POS_TEXCOORD];
 	uint32_t			cs_user_data[4];
 
+        /**
+         * last_block allows disabling threads at the farthermost grid boundary.
+         * Full blocks as specified by "block" are launched, but the threads
+         * outside of "last_block" dimensions are disabled.
+         *
+         * If a block touches the grid boundary in the i-th axis, threads with
+         * THREAD_ID[i] >= last_block[i] are disabled.
+         *
+         * If last_block[i] is 0, it has the same behavior as last_block[i] = block[i],
+         * meaning no effect.
+         *
+         * It's equivalent to doing this at the beginning of the compute shader:
+         *
+         *   for (i = 0; i < 3; i++) {
+         *      if (block_id[i] == grid[i] - 1 &&
+         *          last_block[i] && last_block[i] >= thread_id[i])
+         *         return;
+         *   }
+         * (this could be moved into pipe_grid_info)
+         */
+        uint compute_last_block[3];
+
 	/* Vertex and index buffers. */
 	bool				vertex_buffers_dirty;
 	bool				vertex_buffer_pointer_dirty;