Bug 1298756 - Use uint8_t/uint16_t as underlying type for enums from webidl. r=bz

MozReview-Commit-ID: 3uS9s5ZrPFd

--HG--
extra : rebase_source : ff64b4468ee99ba08fd8638298a27711b7fb6393

dom/animation/KeyframeEffectReadOnly.h

@@ -48,8 +48,8 @@ class GlobalObject;
 class OwningElementOrCSSPseudoElement;
 class UnrestrictedDoubleOrKeyframeAnimationOptions;
 class UnrestrictedDoubleOrKeyframeEffectOptions;
-enum class IterationCompositeOperation : uint32_t;
-enum class CompositeOperation : uint32_t;
+enum class IterationCompositeOperation : uint8_t;
+enum class CompositeOperation : uint8_t;
 struct AnimationPropertyDetails;
 }
 

dom/base/nsGlobalWindow.h

@@ -115,7 +115,7 @@ class DocGroup;
 class External;
 class Function;
 class Gamepad;
-enum class ImageBitmapFormat : uint32_t;
+enum class ImageBitmapFormat : uint8_t;
 class IdleRequest;
 class IdleRequestCallback;
 class Location;

dom/base/nsIDocument.h

@@ -149,7 +149,7 @@ class MediaQueryList;
 class GlobalObject;
 class NodeFilter;
 class NodeIterator;
-enum class OrientationType : uint32_t;
+enum class OrientationType : uint8_t;
 class ProcessingInstruction;
 class Promise;
 class StyleSheetList;
@@ -3037,9 +3037,10 @@ protected:
 #ifdef MOZILLA_INTERNAL_API
   // Our visibility state
   mozilla::dom::VisibilityState mVisibilityState;
-  static_assert(sizeof(mozilla::dom::VisibilityState) == sizeof(uint32_t), "Error size of mVisibilityState and mDummy");
+  static_assert(sizeof(mozilla::dom::VisibilityState) == sizeof(uint8_t),
+                "Error size of mVisibilityState and mDummy");
 #else
-  uint32_t mDummy;
+  uint8_t mDummy;
 #endif
 
   // True if BIDI is enabled.

dom/bindings/Codegen.py

@@ -9625,15 +9625,25 @@ class CGEnum(CGThing):
     def nEnumStrings(self):
         return len(self.enum.values()) + 1
 
+    def underlyingType(self):
+        count = self.nEnumStrings()
+        if count <= 256:
+            return "uint8_t"
+        if count <= 65536:
+            return "uint16_t"
+        raise ValueError("Enum " + self.enum.identifier.name +
+                         " has more than 65536 values")
+
     def declare(self):
         decl = fill(
             """
-            enum class ${name} : uint32_t {
+            enum class ${name} : ${ty} {
               $*{enums}
               EndGuard_
             };
             """,
             name=self.enum.identifier.name,
+            ty=self.underlyingType(),
             enums=",\n".join(map(getEnumValueName, self.enum.values())) + ",\n")
         strings = CGNamespace(self.stringsNamespace(),
                               CGGeneric(declare="extern const EnumEntry %s[%d];\n"

dom/cache/CacheStorage.h

@@ -28,7 +28,7 @@ namespace ipc {
 
 namespace dom {
 
-enum class CacheStorageNamespace : uint32_t;
+enum class CacheStorageNamespace : uint8_t;
 class Promise;
 
 namespace workers {

dom/canvas/CanvasPath.h

@@ -15,7 +15,7 @@
 namespace mozilla {
 namespace dom {
 
-enum class CanvasWindingRule : uint32_t;
+enum class CanvasWindingRule : uint8_t;
 class SVGMatrix;
 
 class CanvasPath final :

dom/canvas/ImageBitmap.h

@@ -52,7 +52,7 @@ class File;
 class HTMLCanvasElement;
 class HTMLImageElement;
 class HTMLVideoElement;
-enum class ImageBitmapFormat : uint32_t;
+enum class ImageBitmapFormat : uint8_t;
 class ImageData;
 class ImageUtils;
 template<typename T> class MapDataIntoBufferSource;

dom/canvas/ImageUtils.h

@@ -21,7 +21,7 @@ class ErrorResult;
 namespace dom {
 
 struct ChannelPixelLayout;
-enum class ImageBitmapFormat : uint32_t;
+enum class ImageBitmapFormat : uint8_t;
 
 typedef nsTArray<ChannelPixelLayout> ImagePixelLayout;
 

dom/html/nsBrowserElement.h

@@ -22,8 +22,8 @@ struct BrowserElementDownloadOptions;
 struct BrowserElementExecuteScriptOptions;
 class BrowserElementNextPaintEventCallback;
 class DOMRequest;
-enum class BrowserFindCaseSensitivity: uint32_t;
-enum class BrowserFindDirection: uint32_t;
+enum class BrowserFindCaseSensitivity: uint8_t;
+enum class BrowserFindDirection: uint8_t;
 } // namespace dom
 
 class ErrorResult;

dom/media/webaudio/AudioContext.h

@@ -42,7 +42,7 @@ class AudioNodeStream;
 
 namespace dom {
 
-enum class AudioContextState : uint32_t;
+enum class AudioContextState : uint8_t;
 class AnalyserNode;
 class AudioBuffer;
 class AudioBufferSourceNode;
@@ -71,7 +71,7 @@ class WaveShaperNode;
 class PeriodicWave;
 struct PeriodicWaveConstraints;
 class Promise;
-enum class OscillatorType : uint32_t;
+enum class OscillatorType : uint8_t;
 
 // This is addrefed by the OscillatorNodeEngine on the main thread
 // and then used from the MSG thread.

dom/media/webaudio/AudioNodeStream.cpp

@@ -350,11 +350,6 @@ AudioNodeStream::SetChannelMixingParametersImpl(uint32_t aNumberOfChannels,
                                                 ChannelCountMode aChannelCountMode,
                                                 ChannelInterpretation aChannelInterpretation)
 {
-  // Make sure that we're not clobbering any significant bits by fitting these
-  // values in 16 bits.
-  MOZ_ASSERT(int(aChannelCountMode) < INT16_MAX);
-  MOZ_ASSERT(int(aChannelInterpretation) < INT16_MAX);
-
   mNumberOfInputChannels = aNumberOfChannels;
   mChannelCountMode = aChannelCountMode;
   mChannelInterpretation = aChannelInterpretation;

dom/workers/WorkerScope.h

@@ -23,7 +23,7 @@ class Console;
 class Crypto;
 class Function;
 class IDBFactory;
-enum class ImageBitmapFormat : uint32_t;
+enum class ImageBitmapFormat : uint8_t;
 class Performance;
 class Promise;
 class RequestOrUSVString;

gfx/vr/gfxVR.h

@@ -21,8 +21,8 @@ namespace layers {
 class PTextureParent;
 }
 namespace dom {
-enum class GamepadMappingType : uint32_t;
-enum class GamepadHand : uint32_t;
+enum class GamepadMappingType : uint8_t;
+enum class GamepadHand : uint8_t;
 struct GamepadPoseState;
 }
 namespace gfx {

layout/style/nsStyleConsts.h

@@ -314,8 +314,8 @@ enum class StyleOrient : uint8_t {
 // See AnimationEffectReadOnly.webidl
 // and mozilla/dom/AnimationEffectReadOnlyBinding.h
 namespace dom {
-enum class PlaybackDirection : uint32_t;
-enum class FillMode : uint32_t;
+enum class PlaybackDirection : uint8_t;
+enum class FillMode : uint8_t;
 }
 
 // See nsStyleDisplay