Add FromAPI / ToAPI helpers for dawn_native

Helps to avoid explicitly using reinterpret_cast

Change-Id: I4df0e7094c7d8460385c6f23dac529ace9df9bdc
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/67605
Auto-Submit: Austin Eng <enga@chromium.org>
Reviewed-by: Loko Kung <lokokung@google.com>
Commit-Queue: Austin Eng <enga@chromium.org>

generator/dawn_json_generator.py

@@ -818,6 +818,10 @@ class MultiGeneratorFromDawnJSON(Generator):
                 FileRender('dawn_native/ValidationUtils.cpp',
                            'src/dawn_native/ValidationUtils_autogen.cpp',
                            frontend_params))
+            renders.append(
+                FileRender('dawn_native/dawn_platform.h',
+                           'src/dawn_native/dawn_platform_autogen.h',
+                           frontend_params))
             renders.append(
                 FileRender('dawn_native/wgpu_structs.h',
                            'src/dawn_native/wgpu_structs_autogen.h',

generator/templates/dawn_native/dawn_platform.h

@@ -0,0 +1,64 @@
+//* Copyright 2021 The Dawn Authors
+//*
+//* Licensed under the Apache License, Version 2.0 (the "License");
+//* you may not use this file except in compliance with the License.
+//* You may obtain a copy of the License at
+//*
+//*     http://www.apache.org/licenses/LICENSE-2.0
+//*
+//* Unless required by applicable law or agreed to in writing, software
+//* distributed under the License is distributed on an "AS IS" BASIS,
+//* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+//* See the License for the specific language governing permissions and
+//* limitations under the License.
+
+#ifndef DAWNNATIVE_DAWN_PLATFORM_AUTOGEN_H_
+#define DAWNNATIVE_DAWN_PLATFORM_AUTOGEN_H_
+
+#include "dawn/webgpu_cpp.h"
+#include "dawn_native/Forward.h"
+
+// Use our autogenerated version of the wgpu structures that point to dawn_native object types
+// (wgpu::Buffer is dawn_native::BufferBase*)
+#include <dawn_native/wgpu_structs_autogen.h>
+
+namespace dawn_native {
+
+    {% for type in by_category["structure"] %}
+        inline const {{as_cType(type.name)}}* ToAPI(const {{as_cppType(type.name)}}* rhs) {
+            return reinterpret_cast<const {{as_cType(type.name)}}*>(rhs);
+        }
+
+        inline {{as_cType(type.name)}}* ToAPI({{as_cppType(type.name)}}* rhs) {
+            return reinterpret_cast<{{as_cType(type.name)}}*>(rhs);
+        }
+
+        inline const {{as_cppType(type.name)}}* FromAPI(const {{as_cType(type.name)}}* rhs) {
+            return reinterpret_cast<const {{as_cppType(type.name)}}*>(rhs);
+        }
+
+        inline {{as_cppType(type.name)}}* FromAPI({{as_cType(type.name)}}* rhs) {
+            return reinterpret_cast<{{as_cppType(type.name)}}*>(rhs);
+        }
+    {% endfor %}
+
+    {% for type in by_category["object"] %}
+        inline const {{as_cType(type.name)}}Impl* ToAPI(const {{as_cppType(type.name)}}Base* rhs) {
+            return reinterpret_cast<const {{as_cType(type.name)}}Impl*>(rhs);
+        }
+
+        inline {{as_cType(type.name)}}Impl* ToAPI({{as_cppType(type.name)}}Base* rhs) {
+            return reinterpret_cast<{{as_cType(type.name)}}Impl*>(rhs);
+        }
+
+        inline const {{as_cppType(type.name)}}Base* FromAPI(const {{as_cType(type.name)}}Impl* rhs) {
+            return reinterpret_cast<const {{as_cppType(type.name)}}Base*>(rhs);
+        }
+
+        inline {{as_cppType(type.name)}}Base* FromAPI({{as_cType(type.name)}}Impl* rhs) {
+            return reinterpret_cast<{{as_cppType(type.name)}}Base*>(rhs);
+        }
+    {% endfor %}
+}
+
+#endif  // DAWNNATIVE_DAWN_PLATFORM_AUTOGEN_H_

src/dawn_native/BUILD.gn

@@ -105,6 +105,7 @@ dawn_json_generator("dawn_native_utils_gen") {
     "src/dawn_native/ChainUtils_autogen.h",
     "src/dawn_native/ChainUtils_autogen.cpp",
     "src/dawn_native/ProcTable.cpp",
+    "src/dawn_native/dawn_platform_autogen.h",
     "src/dawn_native/wgpu_structs_autogen.h",
     "src/dawn_native/wgpu_structs_autogen.cpp",
     "src/dawn_native/ValidationUtils_autogen.h",

src/dawn_native/CommandEncoder.h

@@ -103,9 +103,6 @@ namespace dawn_native {
         uint64_t mDebugGroupStackSize = 0;
     };
 
-    // For the benefit of template generation.
-    using CommandEncoderBase = CommandEncoder;
-
 }  // namespace dawn_native
 
 #endif  // DAWNNATIVE_COMMANDENCODER_H_

src/dawn_native/ComputePassEncoder.h

@@ -69,9 +69,6 @@ namespace dawn_native {
         Ref<CommandEncoder> mCommandEncoder;
     };
 
-    // For the benefit of template generation.
-    using ComputePassEncoderBase = ComputePassEncoder;
-
 }  // namespace dawn_native
 
 #endif  // DAWNNATIVE_COMPUTEPASSENCODER_H_

src/dawn_native/Forward.h

@@ -59,6 +59,13 @@ namespace dawn_native {
 
     struct Format;
 
+    // Aliases for frontend-only types.
+    using CommandEncoderBase = CommandEncoder;
+    using ComputePassEncoderBase = ComputePassEncoder;
+    using RenderBundleEncoderBase = RenderBundleEncoder;
+    using RenderPassEncoderBase = RenderPassEncoder;
+    using SurfaceBase = Surface;
+
 }  // namespace dawn_native
 
 #endif  // DAWNNATIVE_FORWARD_H_

src/dawn_native/RenderBundleEncoder.h

@@ -49,9 +49,6 @@ namespace dawn_native {
         EncodingContext mBundleEncodingContext;
     };
 
-    // For the benefit of template generation.
-    using RenderBundleEncoderBase = RenderBundleEncoder;
-
 }  // namespace dawn_native
 
 #endif  // DAWNNATIVE_RENDERBUNDLEENCODER_H_

src/dawn_native/RenderPassEncoder.h

@@ -82,9 +82,6 @@ namespace dawn_native {
         bool mOcclusionQueryActive = false;
     };
 
-    // For the benefit of template generation.
-    using RenderPassEncoderBase = RenderPassEncoder;
-
 }  // namespace dawn_native
 
 #endif  // DAWNNATIVE_RENDERPASSENCODER_H_

src/dawn_native/Surface.h

@@ -105,9 +105,6 @@ namespace dawn_native {
         const absl::FormatConversionSpec& spec,
         absl::FormatSink* s);
 
-    // For the benefit of template generation.
-    using SurfaceBase = Surface;
-
 }  // namespace dawn_native
 
 #endif  // DAWNNATIVE_SURFACE_H_

src/dawn_native/dawn_platform.h

@@ -18,9 +18,7 @@
 // Use webgpu_cpp to have the enum and bitfield definitions
 #include <dawn/webgpu_cpp.h>
 
-// Use our autogenerated version of the wgpu structures that point to dawn_native object types
-// (wgpu::Buffer is dawn_native::BufferBase*)
-#include <dawn_native/wgpu_structs_autogen.h>
+#include <dawn_native/dawn_platform_autogen.h>
 
 namespace dawn_native {
     // Extra buffer usages