venus: Erase pViewports and pScissors in fewer cases

We should avoid erasing VkGraphicsPipelineCreateInfo when possible
because the erasure add cpu overhead. Do not erase pViewports if
viewportCount is 0. Do not erase pScissors if scissorCount is 0.

Signed-off-by: Lina Versace <linyaa@google.com>
Reviewed-by: Yiwei Zhang <zzyiwei@chromium.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/22419>

diff --git a/src/virtio/vulkan/vn_pipeline.c b/src/virtio/vulkan/vn_pipeline.c
index 7ac9404..2da42c8 100644 (file)
--- a/src/virtio/vulkan/vn_pipeline.c
+++ b/src/virtio/vulkan/vn_pipeline.c
@@ -557,11 +557,12 @@ vn_fix_graphics_pipeline_create_info(
       /* Ignore pViewports?
        *    VUID-VkGraphicsPipelineCreateInfo-pDynamicStates-04130
        *
-       * Even if pViewportState is non-null, we must not dereference it if it
-       * is ignored.
+       * If viewportCount is 0, then venus encoder will ignore pViewports and
+       * we do not need to erase it.
        */
       if (!fix.ignore_viewport_state && info->pViewportState &&
-          info->pViewportState->pViewports) {
+          info->pViewportState->pViewports &&
+          info->pViewportState->viewportCount) {
          const bool has_dynamic_viewport =
             has_pre_raster_state && (has_dynamic_state.viewport ||
                                      has_dynamic_state.viewport_with_count);
@@ -575,11 +576,12 @@ vn_fix_graphics_pipeline_create_info(
       /* Ignore pScissors?
        *    VUID-VkGraphicsPipelineCreateInfo-pDynamicStates-04131
        *
-       * Even if pViewportState is non-null, we must not dereference it if it
-       * is ignored.
+       * If scissorCount is 0, then venus encoder will ignore pScissors and we
+       * do not need to erase it.
        */
       if (!fix.ignore_viewport_state && info->pViewportState &&
-          info->pViewportState->pScissors) {
+          info->pViewportState->pScissors &&
+          info->pViewportState->scissorCount) {
          const bool has_dynamic_scissor =
             has_pre_raster_state && (has_dynamic_state.scissor ||
                                      has_dynamic_state.scissor_with_count);