WIP: Bug 1622846 - Support WebGPU adapter isFallbackAdapter r=emilio

Differential Revision: https://phabricator.services.mozilla.com/D133208

dom/webgpu/Adapter.cpp

@@ -26,7 +26,7 @@ Adapter::Adapter(Instance* const aParent,
       mId(aInfo.id),
       mFeatures(new AdapterFeatures(this)),
       mLimits(new SupportedLimits(this, aInfo.limits)),
-      mIsSoftware(aInfo.ty == ffi::WGPUDeviceType_Cpu) {}
+      mIsFallbackAdapter(aInfo.ty == ffi::WGPUDeviceType_Cpu) {}
 
 Adapter::~Adapter() { Cleanup(); }
 
@@ -39,7 +39,6 @@ void Adapter::Cleanup() {
 
 const RefPtr<AdapterFeatures>& Adapter::Features() const { return mFeatures; }
 const RefPtr<SupportedLimits>& Adapter::Limits() const { return mLimits; }
-bool Adapter::IsSoftware() const { return mIsSoftware; }
 
 already_AddRefed<dom::Promise> Adapter::RequestDevice(
     const dom::GPUDeviceDescriptor& aDesc, ErrorResult& aRv) {

dom/webgpu/Adapter.h

@@ -47,14 +47,14 @@ class Adapter final : public ObjectBase, public ChildOf<Instance> {
   // to unlink them in CC unlink.
   RefPtr<AdapterFeatures> mFeatures;
   RefPtr<SupportedLimits> mLimits;
-  const bool mIsSoftware = false;
+  const bool mIsFallbackAdapter = false;
 
  public:
   Adapter(Instance* const aParent, const ffi::WGPUAdapterInformation& aInfo);
   void GetName(nsString& out) const { out = mName; }
   const RefPtr<AdapterFeatures>& Features() const;
   const RefPtr<SupportedLimits>& Limits() const;
-  bool IsSoftware() const;
+  bool IsFallbackAdapter() const { return mIsFallbackAdapter; }
 
   already_AddRefed<dom::Promise> RequestDevice(
       const dom::GPUDeviceDescriptor& aDesc, ErrorResult& aRv);

dom/webgpu/ipc/WebGPUParent.cpp

@@ -235,6 +235,7 @@ ipc::IPCResult WebGPUParent::RecvInstanceRequestAdapter(
     options.power_preference = static_cast<ffi::WGPUPowerPreference>(
         aOptions.mPowerPreference.Value());
   }
+  options.force_fallback_adapter = aOptions.mForceFallbackAdapter;
   // TODO: make available backends configurable by prefs
 
   ErrorBuffer error;

dom/webgpu/ipc/WebGPUSerialize.h

@@ -31,7 +31,7 @@ DEFINE_IPC_SERIALIZER_FFI_ENUM(mozilla::webgpu::ffi::WGPUHostMap);
 DEFINE_IPC_SERIALIZER_WITHOUT_FIELDS(mozilla::dom::GPUCommandBufferDescriptor);
 
 DEFINE_IPC_SERIALIZER_WITH_FIELDS(mozilla::dom::GPURequestAdapterOptions,
-                                  mPowerPreference);
+                                  mPowerPreference, mForceFallbackAdapter);
 
 DEFINE_IPC_SERIALIZER_WITH_FIELDS(mozilla::webgpu::ScopedError, operationError,
                                   validationMessage);

dom/webidl/WebGPU.webidl

@@ -82,6 +82,7 @@ enum GPUPowerPreference {
 
 dictionary GPURequestAdapterOptions {
     GPUPowerPreference powerPreference;
+    boolean forceFallbackAdapter = false;
 };
 
 [Pref="dom.webgpu.enabled",
@@ -132,7 +133,7 @@ interface GPUAdapter {
     readonly attribute DOMString name;
     [SameObject] readonly attribute GPUAdapterFeatures features;
     [SameObject] readonly attribute GPUSupportedLimits limits;
-    readonly attribute boolean isSoftware;
+    readonly attribute boolean isFallbackAdapter;
 
     [NewObject]
     Promise<GPUDevice> requestDevice(optional GPUDeviceDescriptor descriptor = {});