Implement wgsl_language_features in wgpu

Signed-off-by: sagudev <16504129+sagudev@users.noreply.github.com>

wgpu/Cargo.toml

@@ -187,6 +187,7 @@ optional = true
 
 [dependencies]
 arrayvec.workspace = true
+bitflags.workspace = true
 document-features.workspace = true
 log.workspace = true
 parking_lot.workspace = true

wgpu/src/api/instance.rs

@@ -2,6 +2,23 @@ use parking_lot::Mutex;
 
 use crate::{dispatch::InstanceInterface, *};
 
+bitflags::bitflags! {
+    /// WGSL language extensions.
+    ///
+    /// WGSL spec.: <https://www.w3.org/TR/WGSL/#language-extensions-sec>
+    #[derive(Debug, Clone, PartialEq, PartialOrd, Ord, Eq, Hash)]
+    pub struct WGSLLanguageFeatures: u32 {
+        /// <https://www.w3.org/TR/WGSL/#language_extension-readonly_and_readwrite_storage_textures>
+        const ReadOnlyAndReadWriteStorageTextures = 1 << 0;
+        /// <https://www.w3.org/TR/WGSL/#language_extension-packed_4x8_integer_dot_product>
+        const Packed4x8IntegerDotProduct = 1 << 1;
+        /// <https://www.w3.org/TR/WGSL/#language_extension-unrestricted_pointer_parameters>
+        const UnrestrictedPointerParameters = 1 << 2;
+        /// <https://www.w3.org/TR/WGSL/#language_extension-pointer_composite_access>
+        const PointerCompositeAccess = 1 << 3;
+    }
+}
+
 use std::future::Future;
 
 /// Context for all other wgpu objects. Instance of wgpu.
@@ -385,4 +402,12 @@ impl Instance {
     pub fn generate_report(&self) -> Option<wgc::global::GlobalReport> {
         self.inner.as_core_opt().map(|ctx| ctx.generate_report())
     }
+
+    /// Returns set of supported WGSL language extensions supported by this instance
+    ///
+    /// <https://www.w3.org/TR/webgpu/#gpuwgsllanguagefeatures>
+    #[cfg(feature = "wgsl")]
+    pub fn wgsl_language_features(&self) -> WGSLLanguageFeatures {
+        self.inner.wgsl_language_features()
+    }
 }

wgpu/src/backend/webgpu.rs

@@ -1562,6 +1562,40 @@ impl dispatch::InstanceInterface for ContextWebGpu {
         // Devices are automatically polled.
         true
     }
+
+    #[cfg(feature = "wgsl")]
+    fn wgsl_language_features(&self) -> crate::WGSLLanguageFeatures {
+        let mut wgsl_language_features = crate::WGSLLanguageFeatures::empty();
+        if let Some(gpu) = &self.gpu {
+            gpu.wgsl_language_features()
+                .keys()
+                .into_iter()
+                .map(|wlf| wlf.expect("WGSLLanguageFeatures elements should be valid"))
+                .map(|wlf| {
+                    wlf.as_string()
+                        .expect("WGSLLanguageFeatures should be string set")
+                })
+                .filter_map(|wlf| match wlf.as_str() {
+                    "readonly_and_readwrite_storage_textures" => {
+                        Some(crate::WGSLLanguageFeatures::ReadOnlyAndReadWriteStorageTextures)
+                    }
+                    "packed_4x8_integer_dot_product" => {
+                        Some(crate::WGSLLanguageFeatures::Packed4x8IntegerDotProduct)
+                    }
+                    "unrestricted_pointer_parameters" => {
+                        Some(crate::WGSLLanguageFeatures::UnrestrictedPointerParameters)
+                    }
+                    "pointer_composite_access" => {
+                        Some(crate::WGSLLanguageFeatures::PointerCompositeAccess)
+                    }
+                    _ => None,
+                })
+                .for_each(|wlf| {
+                    wgsl_language_features |= wlf;
+                })
+        }
+        wgsl_language_features
+    }
 }
 
 impl Drop for ContextWebGpu {

wgpu/src/backend/wgpu_core.rs

@@ -850,6 +850,16 @@ impl dispatch::InstanceInterface for ContextWgpuCore {
             Err(err) => self.handle_error_fatal(err, "Instance::poll_all_devices"),
         }
     }
+
+    #[cfg(feature = "wgsl")]
+    fn wgsl_language_features(&self) -> crate::WGSLLanguageFeatures {
+        use wgc::naga::front::wgsl::WGSLLanguageExtension;
+        let wgsl_language_features = crate::WGSLLanguageFeatures::empty();
+        WGSLLanguageExtension::all()
+            .iter()
+            .for_each(|wle| match *wle {});
+        wgsl_language_features
+    }
 }
 
 impl dispatch::AdapterInterface for CoreAdapter {

wgpu/src/dispatch.rs

@@ -100,6 +100,9 @@ pub trait InstanceInterface: CommonTraits {
     ) -> Pin<Box<dyn RequestAdapterFuture>>;
 
     fn poll_all_devices(&self, force_wait: bool) -> bool;
+
+    #[cfg(feature = "wgsl")]
+    fn wgsl_language_features(&self) -> crate::WGSLLanguageFeatures;
 }
 
 pub trait AdapterInterface: CommonTraits {