Enable Partial Binding on DX12 (#6734)

CHANGELOG.md

@@ -53,6 +53,12 @@ By @cwfitzgerald in [#6619](https://github.com/gfx-rs/wgpu/pull/6619).
 A regression introduced in 23.0.0 caused lifetimes of render and compute passes to be incorrectly enforced. While this is not
 a soundness issue, the intent is to move an error from runtime to compile time. This issue has been fixed and restored to the 22.0.0 behavior.
 
+### Bindless (`binding_array`) Grew More Capabilities
+
+- DX12 now supports `PARTIALLY_BOUND_BINDING_ARRAY` on Resource Binding Tier 3 Hardware. This is most D3D12 hardware [D3D12 Feature Table] for more information on what hardware supports this feature. By @cwfitzgerald in [#6734](https://github.com/gfx-rs/wgpu/pull/6734).
+
+[D3D12 Feature Table]: https://d3d12infodb.boolka.dev/FeatureTable.html
+
 ### `Device::create_shader_module_unchecked` Renamed and Now Has Configuration Options
 
 `create_shader_module_unchecked` became `create_shader_module_trusted`.

wgpu-hal/src/dx12/adapter.rs

@@ -344,6 +344,12 @@ impl super::Adapter {
             shader_model >= naga::back::hlsl::ShaderModel::V5_1,
         );
 
+        // See note below the table https://learn.microsoft.com/en-us/windows/win32/direct3d12/hardware-support
+        features.set(
+            wgt::Features::PARTIALLY_BOUND_BINDING_ARRAY,
+            options.ResourceBindingTier.0 >= Direct3D12::D3D12_RESOURCE_BINDING_TIER_3.0,
+        );
+
         let bgra8unorm_storage_supported = {
             let mut bgra8unorm_info = Direct3D12::D3D12_FEATURE_DATA_FORMAT_SUPPORT {
                 Format: Dxgi::Common::DXGI_FORMAT_B8G8R8A8_UNORM,

wgpu-types/src/lib.rs

@@ -628,6 +628,10 @@ bitflags::bitflags! {
         const UNIFORM_BUFFER_AND_STORAGE_TEXTURE_ARRAY_NON_UNIFORM_INDEXING = 1 << 31;
         /// Allows the user to create bind groups containing arrays with less bindings than the BindGroupLayout.
         ///
+        /// Supported platforms:
+        /// - Vulkan
+        /// - DX12
+        ///
         /// This is a native only feature.
         const PARTIALLY_BOUND_BINDING_ARRAY = 1 << 32;
         /// Allows the user to call [`RenderPass::multi_draw_indirect`] and [`RenderPass::multi_draw_indexed_indirect`].