Implement the builder error callback in the backends

This makes the Builder base class retain the error status, if any, and
call the callback on GetResult (or ~Builder, whichever comes first).

generator/main.py

@@ -309,15 +309,24 @@ def as_backendType(typ):
     else:
         return as_cType(typ.name)
 
+def cpp_native_methods(types, typ):
+    methods = typ.methods + typ.native_methods
+
+    if typ.is_builder:
+        methods.append(Method(Name('set error callback'), types['void'], [
+            MethodArgument(Name('callback'), types['builder error callback'], 'value'),
+            MethodArgument(Name('userdata1'), types['callback userdata'], 'value'),
+            MethodArgument(Name('userdata2'), types['callback userdata'], 'value'),
+        ]))
+
+    return methods
+
 def c_native_methods(types, typ):
-    return cpp_native_methods(typ) + [
+    return cpp_native_methods(types, typ) + [
         Method(Name('reference'), types['void'], []),
         Method(Name('release'), types['void'], []),
     ]
 
-def cpp_native_methods(typ):
-    return typ.methods + typ.native_methods
-
 def debug(text):
     print(text)
 
@@ -376,7 +385,7 @@ def main():
         renders.append(FileRender('api.c', 'nxt/nxt.c', [base_params, api_params, c_params]))
 
     if 'nxtcpp' in targets:
-        additional_params = {'native_methods': cpp_native_methods}
+        additional_params = {'native_methods': lambda typ: cpp_native_methods(api_params['types'], typ)}
         renders.append(FileRender('apicpp.h', 'nxt/nxtcpp.h', [base_params, api_params, additional_params]))
         renders.append(FileRender('apicpp.cpp', 'nxt/nxtcpp.cpp', [base_params, api_params, additional_params]))
 

generator/templates/BackendProcTable.cpp

@@ -91,7 +91,7 @@ namespace {{namespace}} {
                     {%- endfor -%}
                 ) {
                     {% if type.is_builder and method.name.canonical_case() not in ("release", "reference") %}
-                        if (self->WasConsumed()) return false;
+                        if (!self->CanBeUsed()) return false;
                     {% else %}
                         (void) self;
                     {% endif %}
@@ -121,6 +121,8 @@ namespace {{namespace}} {
                         {%- endfor -%}
                     );
 
+                    //* Some function have very heavy checks in a seperate method, so that they
+                    //* can be skipped in the NonValidatingEntryPoints.
                     {% if suffix in methodsWithExtraValidation %}
                         if (valid) {
                             valid = self->Validate{{method.name.CamelCase()}}(
@@ -130,12 +132,27 @@ namespace {{namespace}} {
                             );
                         }
                     {% endif %}
-                    //* TODO Do the hand-written checks if necessary
-                    //* On success, forward the arguments to the method, else error out without calling it
+
+                    //* If there is an error we forward it appropriately.
                     if (!valid) {
-                        // TODO get the device and give it the error?
-                        std::cout << "Error in {{suffix}}" << std::endl;
+                        //* An error in a builder methods is always handled by the builder
+                        {% if type.is_builder %}
+                            //* HACK(cwallez@chromium.org): special casing GetResult so that the error callback
+                            //* is called if needed. Without this, no call to HandleResult would happen, and the
+                            //* error callback would always get called with an Unknown status
+                            {% if method.name.canonical_case() == "get result" %}
+                                {{as_backendType(method.return_type)}} fakeResult = nullptr;
+                                bool shouldBeFalse = self->HandleResult(fakeResult);
+                                assert(shouldBeFalse == false);
+                            {% else %}
+                                self->HandleError("Error in {{suffix}}");
+                            {% endif %}
+                        {% else %}
+                            // TODO get the device or builder and give it the error?
+                            std::cout << "Error in {{suffix}}" << std::endl;
+                        {% endif %}
                     }
+
                     {% if method.return_type.name.canonical_case() == "void" %}
                         if (!valid) return;
                     {% else %}

generator/templates/api.h

@@ -36,6 +36,7 @@
 // Custom types depending on the target language
 typedef uint64_t nxtCallbackUserdata;
 typedef void (*nxtDeviceErrorCallback)(const char* message, nxtCallbackUserdata userdata);
+typedef void (*nxtBuilderErrorCallback)(nxtBuilderErrorStatus status, const char* message, nxtCallbackUserdata userdata1, nxtCallbackUserdata userdata2);
 
 #ifdef __cplusplus
 extern "C" {

generator/templates/wire/WireClient.cpp

@@ -172,6 +172,14 @@ namespace wire {
                 }
             {% endfor %}
 
+            {% if type.is_builder %}
+                void Client{{as_MethodSuffix(type.name, Name("set error callback"))}}(nxtBuilderErrorCallback callback,
+                                                                                      nxtCallbackUserdata userdata1,
+                                                                                      nxtCallbackUserdata userdata2) {
+                    //TODO(cwallez@chromium.org): will be implemented in a follow-up commit.
+                }
+            {% endif %}
+
             {% if not type.name.canonical_case() == "device" %}
                 //* When an object's refcount reaches 0, notify the server side of it and delete it.
                 void Client{{as_MethodSuffix(type.name, Name("release"))}}({{Type}}* obj) {

next.json

@@ -102,6 +102,18 @@
             {"value": 3, "name": "storage buffer"}
         ]
     },
+    "builder error status": {
+        "category": "enum",
+        "values": [
+            {"value": 0, "name": "success"},
+            {"value": 1, "name": "error", "TODO": "cwallez@chromium.org: recoverable errors like GPU OOM"},
+            {"value": 2, "name": "unknown"},
+            {"value": 3, "name": "context lost"}
+        ]
+    },
+    "builder error callback": {
+        "category": "natively defined"
+    },
     "buffer": {
         "category": "object",
         "methods": [

src/backend/common/BindGroup.cpp

@@ -64,11 +64,10 @@ namespace backend {
         BINDGROUP_PROPERTY_LAYOUT = 0x2,
     };
 
-    BindGroupBuilder::BindGroupBuilder(DeviceBase* device)
-        : Builder(device) {
+    BindGroupBuilder::BindGroupBuilder(DeviceBase* device) : Builder(device) {
     }
 
-    BindGroupBase* BindGroupBuilder::GetResult() {
+    BindGroupBase* BindGroupBuilder::GetResultImpl() {
         constexpr int allProperties = BINDGROUP_PROPERTY_USAGE | BINDGROUP_PROPERTY_LAYOUT;
         if ((propertiesSet & allProperties) != allProperties) {
             HandleError("Bindgroup missing properties");
@@ -80,7 +79,6 @@ namespace backend {
             return nullptr;
         }
 
-        MarkConsumed();
         return device->CreateBindGroup(this);
     }
 

src/backend/common/BindGroup.h

@@ -43,12 +43,11 @@ namespace backend {
             std::array<Ref<RefCounted>, kMaxBindingsPerGroup> bindings;
     };
 
-    class BindGroupBuilder : public Builder {
+    class BindGroupBuilder : public Builder<BindGroupBase> {
         public:
             BindGroupBuilder(DeviceBase* device);
 
             // NXT API
-            BindGroupBase* GetResult();
             void SetLayout(BindGroupLayoutBase* layout);
             void SetUsage(nxt::BindGroupUsage usage);
 
@@ -76,6 +75,7 @@ namespace backend {
         private:
             friend class BindGroupBase;
 
+            BindGroupBase* GetResultImpl() override;
             void SetBindingsBase(uint32_t start, uint32_t count, RefCounted* const * objects);
             bool SetBindingsValidationBase(uint32_t start, uint32_t count);
 

src/backend/common/BindGroupLayout.cpp

@@ -101,8 +101,7 @@ namespace backend {
         return bindingInfo;
     }
 
-    BindGroupLayoutBase* BindGroupLayoutBuilder::GetResult() {
-        MarkConsumed();
+    BindGroupLayoutBase* BindGroupLayoutBuilder::GetResultImpl() {
         BindGroupLayoutBase blueprint(this, true);
 
         auto* result = device->GetOrCreateBindGroupLayout(&blueprint, this);

src/backend/common/BindGroupLayout.h

@@ -44,19 +44,20 @@ namespace backend {
             bool blueprint = false;
     };
 
-    class BindGroupLayoutBuilder : public Builder {
+    class BindGroupLayoutBuilder : public Builder<BindGroupLayoutBase> {
         public:
             BindGroupLayoutBuilder(DeviceBase* device);
 
             const BindGroupLayoutBase::LayoutBindingInfo& GetBindingInfo() const;
 
             // NXT API
-            BindGroupLayoutBase* GetResult();
             void SetBindingsType(nxt::ShaderStageBit visibility, nxt::BindingType bindingType, uint32_t start, uint32_t count);
 
         private:
             friend class BindGroupLayoutBase;
 
+            BindGroupLayoutBase* GetResultImpl() override;
+
             BindGroupLayoutBase::LayoutBindingInfo bindingInfo;
     };
 

src/backend/common/Buffer.cpp

@@ -121,7 +121,7 @@ namespace backend {
     BufferBuilder::BufferBuilder(DeviceBase* device) : Builder(device) {
     }
 
-    BufferBase* BufferBuilder::GetResult() {
+    BufferBase* BufferBuilder::GetResultImpl() {
         constexpr int allProperties = BUFFER_PROPERTY_ALLOWED_USAGE | BUFFER_PROPERTY_SIZE;
         if ((propertiesSet & allProperties) != allProperties) {
             HandleError("Buffer missing properties");
@@ -133,7 +133,6 @@ namespace backend {
             return nullptr;
         }
 
-        MarkConsumed();
         return device->CreateBuffer(this);
     }
 
@@ -195,14 +194,13 @@ namespace backend {
         : Builder(device), buffer(buffer) {
     }
 
-    BufferViewBase* BufferViewBuilder::GetResult() {
+    BufferViewBase* BufferViewBuilder::GetResultImpl() {
         constexpr int allProperties = BUFFER_VIEW_PROPERTY_EXTENT;
         if ((propertiesSet & allProperties) != allProperties) {
             HandleError("Buffer view missing properties");
             return nullptr;
         }
 
-        MarkConsumed();
         return device->CreateBufferView(this);
     }
 

src/backend/common/Buffer.h

@@ -52,12 +52,11 @@ namespace backend {
             bool frozen = false;
     };
 
-    class BufferBuilder : public Builder {
+    class BufferBuilder : public Builder<BufferBase> {
         public:
             BufferBuilder(DeviceBase* device);
 
             // NXT API
-            BufferBase* GetResult();
             void SetAllowedUsage(nxt::BufferUsageBit usage);
             void SetInitialUsage(nxt::BufferUsageBit usage);
             void SetSize(uint32_t size);
@@ -65,6 +64,8 @@ namespace backend {
         private:
             friend class BufferBase;
 
+            BufferBase* GetResultImpl() override;
+
             uint32_t size;
             nxt::BufferUsageBit allowedUsage = nxt::BufferUsageBit::None;
             nxt::BufferUsageBit currentUsage = nxt::BufferUsageBit::None;
@@ -85,17 +86,18 @@ namespace backend {
             uint32_t offset;
     };
 
-    class BufferViewBuilder : public Builder {
+    class BufferViewBuilder : public Builder<BufferViewBase> {
         public:
             BufferViewBuilder(DeviceBase* device, BufferBase* buffer);
 
             // NXT API
-            BufferViewBase* GetResult();
             void SetExtent(uint32_t offset, uint32_t size);
 
         private:
             friend class BufferViewBase;
 
+            BufferViewBase* GetResultImpl() override;
+
             Ref<BufferBase> buffer;
             uint32_t offset = 0;
             uint32_t size = 0;

src/backend/common/Builder.cpp

@@ -18,20 +18,69 @@
 
 namespace backend {
 
-    bool Builder::WasConsumed() const {
-        return consumed;
+    bool BuilderBase::CanBeUsed() const {
+        return !consumed && !gotStatus;
     }
 
-    Builder::Builder(DeviceBase* device) : device(device) {
+    void BuilderBase::HandleError(const char* message) {
+        SetStatus(nxt::BuilderErrorStatus::Error, message);
     }
 
-    void Builder::MarkConsumed() {
+    void BuilderBase::SetErrorCallback(nxt::BuilderErrorCallback callback,
+                                   nxt::CallbackUserdata userdata1,
+                                   nxt::CallbackUserdata userdata2) {
+        this->callback = callback;
+        this->userdata1 = userdata1;
+        this->userdata2 = userdata2;
+    }
+
+    BuilderBase::BuilderBase(DeviceBase* device) : device(device) {
+    }
+
+    BuilderBase::~BuilderBase() {
+        if (!consumed && callback != nullptr) {
+            callback(NXT_BUILDER_ERROR_STATUS_UNKNOWN, "Builder destroyed before GetResult", userdata1, userdata2);
+        }
+    }
+
+    void BuilderBase::SetStatus(nxt::BuilderErrorStatus status, const char* message) {
+        ASSERT(status != nxt::BuilderErrorStatus::Success);
+        ASSERT(status != nxt::BuilderErrorStatus::Unknown);
+        ASSERT(!gotStatus); // This is not strictly necessary but something to strive for.
+        gotStatus = true;
+
+        storedStatus = status;
+        storedMessage = std::move(message);
+    }
+
+    bool BuilderBase::HandleResult(RefCounted* result) {
+        // GetResult can only be called once.
         ASSERT(!consumed);
         consumed = true;
-    }
 
-    void Builder::HandleError(const char* message) {
-        device->HandleError(message);
+        // result == nullptr implies there was an error which implies we should have a status set.
+        ASSERT(result != nullptr || gotStatus);
+
+        // If we have any error, then we have to return nullptr
+        if (gotStatus) {
+            ASSERT(storedStatus != nxt::BuilderErrorStatus::Success);
+
+            // The application will never see "result" so we need to remove the
+            // external ref here.
+            if (result != nullptr) {
+                result->Release();
+                result = nullptr;
+            }
+        } else {
+            ASSERT(storedStatus == nxt::BuilderErrorStatus::Success);
+            ASSERT(storedMessage.empty());
+        }
+
+        if (callback) {
+            callback(static_cast<nxtBuilderErrorStatus>(storedStatus), storedMessage.c_str(), userdata1, userdata2);
+        }
+
+        return result != nullptr;
     }
 
 }

src/backend/common/Builder.h

@@ -18,24 +18,92 @@
 #include "Forward.h"
 #include "RefCounted.h"
 
+#include "nxt/nxtcpp.h"
+
+#include <string>
+
 namespace backend {
 
-    class Builder : public RefCounted {
+    // This class implements behavior shared by all builders:
+    //  - Tracking whether GetResult has been called already, needed by the
+    //    autogenerated code to prevent operations on "consumed" builders.
+    //  - The error status callback of the API. The callback is guaranteed to be
+    //    called exactly once with an error, a success, or "unknown" if the
+    //    builder is destroyed; also the builder callback cannot be called before
+    //    either the object is destroyed or GetResult is called.
+    //
+    // It is possible for error to be generated before the error callback is
+    // registered when a builder "set" function performance validation inline.
+    // Because of this we have to store the status in the builder and defer
+    // calling the callback to GetResult.
+
+    class BuilderBase : public RefCounted {
         public:
-            bool WasConsumed() const;
+            // Used by the auto-generated validation to prevent usage of the builder
+            // after GetResult or an error.
+            bool CanBeUsed() const;
+
+            // Set the status of the builder to an error.
             void HandleError(const char* message);
 
-        protected:
-            Builder(DeviceBase* device);
+            // Internal API, to be used by builder and BackendProcTable only.
+            // rReturns true for success cases, and calls the callback with appropriate status.
+            bool HandleResult(RefCounted* result);
 
-            void MarkConsumed();
+            // NXT API
+            void SetErrorCallback(nxt::BuilderErrorCallback callback,
+                                  nxt::CallbackUserdata userdata1,
+                                  nxt::CallbackUserdata userdata2);
+
+        protected:
+            BuilderBase(DeviceBase* device);
+            ~BuilderBase();
 
             DeviceBase* const device;
+            bool gotStatus = false;
 
         private:
+            void SetStatus(nxt::BuilderErrorStatus status, const char* message);
+
+            nxt::BuilderErrorCallback callback = nullptr;
+            nxt::CallbackUserdata userdata1 = 0;
+            nxt::CallbackUserdata userdata2 = 0;
+
+            nxt::BuilderErrorStatus storedStatus = nxt::BuilderErrorStatus::Success;
+            std::string storedMessage;
+
             bool consumed = false;
     };
 
+    // This builder base class is used to capture the calls to GetResult and make sure
+    // that either:
+    //  - There was an error, callback is called with an error and nullptr is returned.
+    //  - There was no error, callback is called with success and a non-null T* is returned.
+    template<typename T>
+    class Builder : public BuilderBase {
+        public:
+            // NXT API
+            T* GetResult();
+
+        protected:
+            using BuilderBase::BuilderBase;
+
+        private:
+            virtual T* GetResultImpl() = 0;
+    };
+
+    template<typename T>
+    T* Builder<T>::GetResult() {
+        T* result = GetResultImpl();
+        // An object can have been returned but failed its initialization, so if an error
+        // happened, return nullptr instead of result.
+        if (HandleResult(result)) {
+            return result;
+        } else {
+            return nullptr;
+        }
+    }
+
 }
 
 #endif // BACKEND_COMMON_BUILDER_H_

src/backend/common/CommandBuffer.cpp

@@ -136,7 +136,7 @@ namespace backend {
     }
 
     CommandBufferBuilder::~CommandBufferBuilder() {
-        if (!WasConsumed()) {
+        if (!commandsAcquired) {
             MoveToIterator();
             FreeCommands(&iterator);
         }
@@ -484,12 +484,13 @@ namespace backend {
     }
 
     CommandIterator CommandBufferBuilder::AcquireCommands() {
+        ASSERT(!commandsAcquired);
+        commandsAcquired = true;
         return std::move(iterator);
     }
 
-    CommandBufferBase* CommandBufferBuilder::GetResult() {
+    CommandBufferBase* CommandBufferBuilder::GetResultImpl() {
         MoveToIterator();
-        MarkConsumed();
         return device->CreateCommandBuffer(this);
     }
 

src/backend/common/CommandBuffer.h

@@ -45,7 +45,7 @@ namespace backend {
             std::set<TextureBase*> texturesTransitioned;
     };
 
-    class CommandBufferBuilder : public Builder {
+    class CommandBufferBuilder : public Builder<CommandBufferBase> {
         public:
             CommandBufferBuilder(DeviceBase* device);
             ~CommandBufferBuilder();
@@ -55,8 +55,6 @@ namespace backend {
             CommandIterator AcquireCommands();
 
             // NXT API
-            CommandBufferBase* GetResult();
-
             void CopyBufferToTexture(BufferBase* buffer, uint32_t bufferOffset,
                                      TextureBase* texture, uint32_t x, uint32_t y, uint32_t z,
                                      uint32_t width, uint32_t height, uint32_t depth, uint32_t level);
@@ -81,11 +79,13 @@ namespace backend {
         private:
             friend class CommandBufferBase;
 
+            CommandBufferBase* GetResultImpl() override;
             void MoveToIterator();
 
             CommandAllocator allocator;
             CommandIterator iterator;
             bool movedToIterator = false;
+            bool commandsAcquired = false;
             // These pointers will remain valid since they are referenced by
             // the bind groups which are referenced by this command buffer.
             std::set<BufferBase*> buffersTransitioned;

src/backend/common/Device.h

@@ -30,7 +30,7 @@ namespace backend {
             ~DeviceBase();
 
             void HandleError(const char* message);
-            void SetErrorCallback(nxt::DeviceErrorCallback, nxt::CallbackUserdata userdata);
+            void SetErrorCallback(nxt::DeviceErrorCallback callback, nxt::CallbackUserdata userdata);
 
             virtual BindGroupBase* CreateBindGroup(BindGroupBuilder* builder) = 0;
             virtual BindGroupLayoutBase* CreateBindGroupLayout(BindGroupLayoutBuilder* builder) = 0;
@@ -86,7 +86,7 @@ namespace backend {
             Caches* caches = nullptr;
 
             nxt::DeviceErrorCallback errorCallback = nullptr;
-            nxt::CallbackUserdata errorUserdata;
+            nxt::CallbackUserdata errorUserdata = 0;
     };
 
 }

src/backend/common/InputState.cpp

@@ -81,7 +81,7 @@ namespace backend {
     InputStateBuilder::InputStateBuilder(DeviceBase* device) : Builder(device) {
     }
 
-    InputStateBase* InputStateBuilder::GetResult() {
+    InputStateBase* InputStateBuilder::GetResultImpl() {
         for (uint32_t location = 0; location < kMaxVertexAttributes; ++location) {
             if (attributesSetMask[location] &&
                     !inputsSetMask[attributeInfos[location].bindingSlot]) {
@@ -90,7 +90,6 @@ namespace backend {
             }
         }
 
-        MarkConsumed();
         return device->CreateInputState(this);
     }
 

src/backend/common/InputState.h

@@ -57,12 +57,11 @@ namespace backend {
             std::array<InputInfo, kMaxVertexInputs> inputInfos;
     };
 
-    class InputStateBuilder : public Builder {
+    class InputStateBuilder : public Builder<InputStateBase> {
         public:
             InputStateBuilder(DeviceBase* device);
 
             // NXT API
-            InputStateBase* GetResult();
             void SetAttribute(uint32_t shaderLocation, uint32_t bindingSlot,
                     nxt::VertexFormat format, uint32_t offset);
             void SetInput(uint32_t bindingSlot, uint32_t stride,
@@ -71,6 +70,8 @@ namespace backend {
         private:
             friend class InputStateBase;
 
+            InputStateBase* GetResultImpl() override;
+
             std::bitset<kMaxVertexAttributes> attributesSetMask;
             std::array<InputStateBase::AttributeInfo, kMaxVertexAttributes> attributeInfos;
             std::bitset<kMaxVertexInputs> inputsSetMask;

src/backend/common/Pipeline.cpp

@@ -98,7 +98,7 @@ namespace backend {
         return stages[stage];
     }
 
-    PipelineBase* PipelineBuilder::GetResult() {
+    PipelineBase* PipelineBuilder::GetResultImpl() {
         // TODO(cwallez@chromium.org): the layout should be required, and put the default objects in the device
         if (!layout) {
             layout = device->CreatePipelineLayoutBuilder()->GetResult();
@@ -107,7 +107,6 @@ namespace backend {
             inputState = device->CreateInputStateBuilder()->GetResult();
         }
 
-        MarkConsumed();
         return device->CreatePipeline(this);
     }
 

src/backend/common/Pipeline.h

@@ -59,7 +59,7 @@ namespace backend {
             Ref<InputStateBase> inputState;
     };
 
-    class PipelineBuilder : public Builder {
+    class PipelineBuilder : public Builder<PipelineBase> {
         public:
             PipelineBuilder(DeviceBase* device);
 
@@ -70,7 +70,6 @@ namespace backend {
             const StageInfo& GetStageInfo(nxt::ShaderStage stage) const;
 
             // NXT API
-            PipelineBase* GetResult();
             void SetLayout(PipelineLayoutBase* layout);
             void SetStage(nxt::ShaderStage stage, ShaderModuleBase* module, const char* entryPoint);
             void SetInputState(InputStateBase* inputState);
@@ -78,6 +77,8 @@ namespace backend {
         private:
             friend class PipelineBase;
 
+            PipelineBase* GetResultImpl() override;
+
             Ref<PipelineLayoutBase> layout;
             nxt::ShaderStageBit stageMask;
             PerStage<StageInfo> stages;

src/backend/common/PipelineLayout.cpp

@@ -39,7 +39,7 @@ namespace backend {
     PipelineLayoutBuilder::PipelineLayoutBuilder(DeviceBase* device) : Builder(device) {
     }
 
-    PipelineLayoutBase* PipelineLayoutBuilder::GetResult() {
+    PipelineLayoutBase* PipelineLayoutBuilder::GetResultImpl() {
         // TODO(cwallez@chromium.org): this is a hack, have the null bind group layout somewhere in the device
         // once we have a cache of BGL
         for (size_t group = 0; group < kMaxBindGroups; ++group) {
@@ -48,7 +48,6 @@ namespace backend {
             }
         }
 
-        MarkConsumed();
         return device->CreatePipelineLayout(this);
     }
 

src/backend/common/PipelineLayout.h

@@ -40,17 +40,18 @@ namespace backend {
             std::bitset<kMaxBindGroups> mask;
     };
 
-    class PipelineLayoutBuilder : public Builder {
+    class PipelineLayoutBuilder : public Builder<PipelineLayoutBase> {
         public:
             PipelineLayoutBuilder(DeviceBase* device);
 
             // NXT API
-            PipelineLayoutBase* GetResult();
             void SetBindGroupLayout(uint32_t groupIndex, BindGroupLayoutBase* layout);
 
         private:
             friend class PipelineLayoutBase;
 
+            PipelineLayoutBase* GetResultImpl() override;
+
             BindGroupLayoutArray bindGroupLayouts;
             std::bitset<kMaxBindGroups> mask;
     };

src/backend/common/Queue.cpp

@@ -30,8 +30,7 @@ namespace backend {
     QueueBuilder::QueueBuilder(DeviceBase* device) : Builder(device) {
     }
 
-    QueueBase* QueueBuilder::GetResult() {
-        MarkConsumed();
+    QueueBase* QueueBuilder::GetResultImpl() {
         return device->CreateQueue(this);
     }
 

src/backend/common/Queue.h

@@ -41,12 +41,12 @@ namespace backend {
             }
     };
 
-    class QueueBuilder : public Builder {
+    class QueueBuilder : public Builder<QueueBase> {
         public:
             QueueBuilder(DeviceBase* device);
 
-            // NXT API
-            QueueBase* GetResult();
+        private:
+            QueueBase* GetResultImpl() override;
     };
 
 }

src/backend/common/Sampler.cpp

@@ -43,11 +43,6 @@ namespace backend {
         return mipMapFilter;
     }
 
-    SamplerBase* SamplerBuilder::GetResult() {
-        MarkConsumed();
-        return device->CreateSampler(this);
-    }
-
     void SamplerBuilder::SetFilterMode(nxt::FilterMode magFilter, nxt::FilterMode minFilter, nxt::FilterMode mipMapFilter) {
         if ((propertiesSet & SAMPLER_PROPERTY_FILTER) != 0) {
             HandleError("Sampler filter property set multiple times");
@@ -59,4 +54,9 @@ namespace backend {
         this->mipMapFilter = mipMapFilter;
         propertiesSet |= SAMPLER_PROPERTY_FILTER;
     }
+
+    SamplerBase* SamplerBuilder::GetResultImpl() {
+        return device->CreateSampler(this);
+    }
+
 }

src/backend/common/Sampler.h

@@ -28,7 +28,7 @@ namespace backend {
             SamplerBase(SamplerBuilder* builder);
     };
 
-    class SamplerBuilder : public Builder {
+    class SamplerBuilder : public Builder<SamplerBase> {
         public:
             SamplerBuilder(DeviceBase* device);
 
@@ -37,12 +37,13 @@ namespace backend {
             nxt::FilterMode GetMipMapFilter() const;
 
             // NXT API
-            SamplerBase* GetResult();
             void SetFilterMode(nxt::FilterMode magFilter, nxt::FilterMode minFilter, nxt::FilterMode mipMapFilter);
 
         private:
             friend class SamplerBase;
 
+            SamplerBase* GetResultImpl() override;
+
             int propertiesSet = 0;
 
             nxt::FilterMode magFilter = nxt::FilterMode::Nearest;

src/backend/common/ShaderModule.cpp

@@ -198,13 +198,12 @@ namespace backend {
         return std::move(spirv);
     }
 
-    ShaderModuleBase* ShaderModuleBuilder::GetResult() {
+    ShaderModuleBase* ShaderModuleBuilder::GetResultImpl() {
         if (spirv.size() == 0) {
             HandleError("Shader module needs to have the source set");
             return nullptr;
         }
 
-        MarkConsumed();
         return device->CreateShaderModule(this);
     }
 

src/backend/common/ShaderModule.h

@@ -71,19 +71,20 @@ namespace backend {
             nxt::ShaderStage executionModel;
     };
 
-    class ShaderModuleBuilder : public Builder {
+    class ShaderModuleBuilder : public Builder<ShaderModuleBase> {
         public:
             ShaderModuleBuilder(DeviceBase* device);
 
             std::vector<uint32_t> AcquireSpirv();
 
             // NXT API
-            ShaderModuleBase* GetResult();
             void SetSource(uint32_t codeSize, const uint32_t* code);
 
         private:
             friend class ShaderModuleBase;
 
+            ShaderModuleBase* GetResultImpl() override;
+
             std::vector<uint32_t> spirv;
     };
 

src/backend/common/Texture.cpp

@@ -121,7 +121,7 @@ namespace backend {
         : Builder(device) {
     }
 
-    TextureBase* TextureBuilder::GetResult() {
+    TextureBase* TextureBuilder::GetResultImpl() {
         constexpr int allProperties = TEXTURE_PROPERTY_DIMENSION | TEXTURE_PROPERTY_EXTENT |
             TEXTURE_PROPERTY_FORMAT | TEXTURE_PROPERTY_MIP_LEVELS | TEXTURE_PROPERTY_ALLOWED_USAGE;
         if ((propertiesSet & allProperties) != allProperties) {
@@ -136,7 +136,6 @@ namespace backend {
 
         // TODO(cwallez@chromium.org): check stuff based on the dimension
 
-        MarkConsumed();
         return device->CreateTexture(this);
     }
 
@@ -223,8 +222,7 @@ namespace backend {
         : Builder(device), texture(texture) {
     }
 
-    TextureViewBase* TextureViewBuilder::GetResult() {
-        MarkConsumed();
+    TextureViewBase* TextureViewBuilder::GetResultImpl() {
         return device->CreateTextureView(this);
     }
 

src/backend/common/Texture.h

@@ -60,12 +60,11 @@ namespace backend {
             bool frozen = false;
     };
 
-    class TextureBuilder : public Builder {
+    class TextureBuilder : public Builder<TextureBase> {
         public:
             TextureBuilder(DeviceBase* device);
 
             // NXT API
-            TextureBase* GetResult();
             void SetDimension(nxt::TextureDimension dimension);
             void SetExtent(uint32_t width, uint32_t height, uint32_t depth);
             void SetFormat(nxt::TextureFormat format);
@@ -76,6 +75,8 @@ namespace backend {
         private:
             friend class TextureBase;
 
+            TextureBase* GetResultImpl() override;
+
             int propertiesSet = 0;
 
             nxt::TextureDimension dimension;
@@ -96,16 +97,15 @@ namespace backend {
             Ref<TextureBase> texture;
     };
 
-    class TextureViewBuilder : public Builder {
+    class TextureViewBuilder : public Builder<TextureViewBase> {
         public:
             TextureViewBuilder(DeviceBase* device, TextureBase* texture);
 
-            // NXT API
-            TextureViewBase* GetResult();
-
         private:
             friend class TextureViewBase;
 
+            TextureViewBase* GetResultImpl() override;
+
             Ref<TextureBase> texture;
     };