radv: skip draws with instance_count == 0

Loosely based on RadeonSI.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>

src/amd/vulkan/radv_cmd_buffer.c

@@ -3696,6 +3696,19 @@ radv_draw(struct radv_cmd_buffer *cmd_buffer,
 		radeon_check_space(cmd_buffer->device->ws,
 				   cmd_buffer->cs, 4096);
 
+	if (likely(!info->indirect)) {
+		/* SI-CI treat instance_count==0 as instance_count==1. There is
+		 * no workaround for indirect draws, but we can at least skip
+		 * direct draws.
+		 */
+		if (unlikely(!info->instance_count))
+			return;
+
+		/* Handle count == 0. */
+		if (unlikely(!info->count && !info->strmout_buffer))
+			return;
+	}
+
 	/* Use optimal packet order based on whether we need to sync the
 	 * pipeline.
 	 */