vulkan/runtime: add vk_image_subresource_slice_count

vk_image_subresource_slice_count is useful when implementing image
barriers. When maintenance9 is enabled,
VkImageSubresourceRange::{baseArrayLayer,layerCount} specify the
slices, rather than layers, to transition. This helper returns
the number of slices specified in the subresource range, accounting
for the VK_REMAINING_ARRAY_LAYERS sentinel.

Reviewed-by: Lars-Ivar Hesselberg Simonsen <lars-ivar.simonsen@arm.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/36176>

src/vulkan/runtime/vk_image.c

@@ -284,6 +284,25 @@ vk_image_expand_aspect_mask(const struct vk_image *image,
    }
 }
 
+uint32_t
+vk_image_subresource_slice_count(const struct vk_device *device,
+                                 const struct vk_image *image,
+                                 const VkImageSubresourceLayers *range)
+{
+   assert(image->image_type == VK_IMAGE_TYPE_3D);
+
+   bool layers_are_slices = device->enabled_features.maintenance9 &&
+      (image->create_flags & VK_IMAGE_CREATE_2D_ARRAY_COMPATIBLE_BIT);
+   uint32_t slices = u_minify(image->extent.depth, range->mipLevel);
+
+   if (!layers_are_slices) {
+      assert(range->baseArrayLayer == 0);
+      return slices;
+   }
+   return range->layerCount == VK_REMAINING_ARRAY_LAYERS ?
+          slices - range->baseArrayLayer : range->layerCount;
+}
+
 VkExtent3D
 vk_image_extent_to_elements(const struct vk_image *image, VkExtent3D extent)
 {

src/vulkan/runtime/vk_image.h

@@ -143,6 +143,11 @@ vk_image_mip_level_extent(const struct vk_image *image,
    return extent;
 }
 
+uint32_t
+vk_image_subresource_slice_count(const struct vk_device *device,
+                                 const struct vk_image *image,
+                                 const VkImageSubresourceLayers *range);
+
 /* This is defined as a macro so that it works for both
  * VkImageSubresourceRange and VkImageSubresourceLayers
  */