[DNM] Experiment: Try introduce a typed ArrayRef bridging wrapper

SwiftCompilerSources/Sources/Basic/Utils.swift

@@ -142,9 +142,9 @@ extension String {
 }
 
 extension Array {
-  public func withBridgedArrayRef<T>(_ c: (BridgedArrayRef) -> T) -> T {
+  public func withBridgedArrayRef<T>(_ c: (BridgedErasedArrayRef) -> T) -> T {
     return withUnsafeBytes { buf in
-      return c(BridgedArrayRef(data: buf.baseAddress!, count: count))
+      return c(BridgedErasedArrayRef(data: buf.baseAddress!, count: count))
     }
   }
 }
@@ -171,7 +171,7 @@ extension Optional where Wrapped == UnsafeMutablePointer<BridgedSwiftObject> {
   }
 }
 
-extension BridgedArrayRef {
+extension BridgedErasedArrayRef {
   public func withElements<T, R>(ofType ty: T.Type, _ c: (UnsafeBufferPointer<T>) -> R) -> R {
     let start = data?.bindMemory(to: ty, capacity: count)
     let buffer = UnsafeBufferPointer(start: start, count: count)

SwiftCompilerSources/Sources/Optimizer/Utilities/BorrowedFromUpdater.swift

@@ -105,7 +105,7 @@ func registerBorrowedFromUpdater() {
       let function = bridgedFunction.function;
       updateBorrowedFrom(in: function, context)
     },
-    { (bridgedCtxt: BridgedPassContext, bridgedPhiArray: BridgedArrayRef) in
+    { (bridgedCtxt: BridgedPassContext, bridgedPhiArray: BridgedErasedArrayRef) in
       let context = FunctionPassContext(_bridged: bridgedCtxt)
       var guaranteedPhis = Stack<Phi>(context)
       defer { guaranteedPhis.deinitialize() }

SwiftCompilerSources/Sources/SIL/Function.swift

@@ -418,7 +418,7 @@ extension Function {
         s._withBridgedStringRef { $0.write(os) }
       },
       // parseFn:
-      { (f: BridgedFunction, str: BridgedStringRef, mode: BridgedFunction.ParseEffectsMode, argumentIndex: Int, paramNames: BridgedArrayRef) -> BridgedFunction.ParsingError in
+      { (f: BridgedFunction, str: BridgedStringRef, mode: BridgedFunction.ParseEffectsMode, argumentIndex: Int, paramNames: BridgedErasedArrayRef) -> BridgedFunction.ParsingError in
         do {
           var parser = StringParser(String(str))
           let function = f.function

include/swift/Basic/BasicBridging.h

@@ -114,23 +114,23 @@ void assertFail(const char * _Nonnull msg, const char * _Nonnull file,
 // MARK: ArrayRef
 //===----------------------------------------------------------------------===//
 
-class BridgedArrayRef {
+class BridgedErasedArrayRef {
 public:
   SWIFT_UNAVAILABLE("Use '.data' instead")
   const void *_Nullable Data;
 
   SWIFT_UNAVAILABLE("Use '.count' instead")
   size_t Length;
 
-  BridgedArrayRef() : Data(nullptr), Length(0) {}
+  BridgedErasedArrayRef() : Data(nullptr), Length(0) {}
 
   SWIFT_NAME("init(data:count:)")
-  BridgedArrayRef(const void *_Nullable data, size_t length)
+  BridgedErasedArrayRef(const void *_Nullable data, size_t length)
       : Data(data), Length(length) {}
 
 #ifdef USED_IN_CPP_SOURCE
   template <typename T>
-  BridgedArrayRef(llvm::ArrayRef<T> arr)
+  BridgedErasedArrayRef(llvm::ArrayRef<T> arr)
       : Data(arr.data()), Length(arr.size()) {}
 
   template <typename T>
@@ -140,12 +140,65 @@ class BridgedArrayRef {
 #endif
 };
 
-SWIFT_NAME("getter:BridgedArrayRef.data(self:)")
+SWIFT_NAME("getter:BridgedErasedArrayRef.data(self:)")
 BRIDGED_INLINE
-const void *_Nullable BridgedArrayRef_data(BridgedArrayRef arr);
+const void *_Nullable BridgedErasedArrayRef_data(BridgedErasedArrayRef arr);
+
+SWIFT_NAME("getter:BridgedErasedArrayRef.count(self:)")
+BRIDGED_INLINE SwiftInt BridgedErasedArrayRef_count(BridgedErasedArrayRef arr);
+
+
+/// Bridgable wrapper for 'llvm::ArrayRef<Element>'.
+template <typename _Element>
+class BridgedArrayRef {
+public:
+  // Seemingly needed for Swift-side conformance.
+  using Element = _Element;
+
+  SWIFT_UNAVAILABLE("Use '.data' instead")
+  const void *_Nullable Data;
+
+  SWIFT_UNAVAILABLE("Use '.count' instead")
+  size_t Length;
+
+  SWIFT_NAME("init(data:count:)")
+  BridgedArrayRef(const Element *_Nullable data, SwiftInt length)
+      : Data(data), Length(length) {}
 
+#ifdef USED_IN_CPP_SOURCE
+  using ArrRefTy = llvm::ArrayRef<Element>;
+
+  BridgedArrayRef(ArrRefTy arrRef)
+    : Data(arrRef.data()), Length(arrRef.size()) {}
+
+  using iterator = typename ArrRefTy::iterator;
+  iterator begin() const { return unbridged().begin(); }
+  iterator end() const { return unbridged().end(); }
+
+  ArrRefTy unbridged() const {
+    return ArrRefTy(static_cast<const Element *>(Data), Length);
+  }
+#endif
+
+  bool empty() const { return Length == 0; }
+
+}
+#ifdef IMPORTING_INTO_ASTGEN
+__attribute__((swift_attr("conforms_to:swiftASTGen.BridgedArrayRefProtocol")))
+#endif
+;
+
+template<typename T>
+SWIFT_NAME("getter:BridgedArrayRef.data(self:)")
+inline const void *_Nullable BridgedArrayRef_data(BridgedArrayRef<T> arr) {
+  return arr.Data;
+}
+
+template<typename T>
 SWIFT_NAME("getter:BridgedArrayRef.count(self:)")
-BRIDGED_INLINE SwiftInt BridgedArrayRef_count(BridgedArrayRef arr);
+inline SwiftInt BridgedArrayRef_count(BridgedArrayRef<T> arr) {
+  return arr.Length;
+}
 
 //===----------------------------------------------------------------------===//
 // MARK: Data

include/swift/Basic/BasicBridgingImpl.h

@@ -16,14 +16,14 @@
 SWIFT_BEGIN_NULLABILITY_ANNOTATIONS
 
 //===----------------------------------------------------------------------===//
-// MARK: BridgedArrayRef
+// MARK: BridgedErasedArrayRef
 //===----------------------------------------------------------------------===//
 
-const void *_Nullable BridgedArrayRef_data(BridgedArrayRef arr) {
+const void *_Nullable BridgedErasedArrayRef_data(BridgedErasedArrayRef arr) {
   return arr.Data;
 }
 
-SwiftInt BridgedArrayRef_count(BridgedArrayRef arr) {
+SwiftInt BridgedErasedArrayRef_count(BridgedErasedArrayRef arr) {
   return static_cast<SwiftInt>(arr.Length);
 }
 

include/swift/SIL/SILBridging.h

@@ -112,7 +112,7 @@ struct OptionalBridgedResultInfo {
 };
 
 struct BridgedResultInfoArray {
-  BridgedArrayRef resultInfoArray;
+  BridgedErasedArrayRef resultInfoArray;
 
 #ifdef USED_IN_CPP_SOURCE
   BridgedResultInfoArray(llvm::ArrayRef<swift::SILResultInfo> results)
@@ -215,7 +215,7 @@ struct BridgedParameterInfo {
 };
 
 struct BridgedParameterInfoArray {
-  BridgedArrayRef parameterInfoArray;
+  BridgedErasedArrayRef parameterInfoArray;
 
 #ifdef USED_IN_CPP_SOURCE
   BridgedParameterInfoArray(llvm::ArrayRef<swift::SILParameterInfo> parameters)
@@ -233,7 +233,7 @@ struct BridgedParameterInfoArray {
 };
 
 struct BridgedYieldInfoArray {
-  BridgedArrayRef yieldInfoArray;
+  BridgedErasedArrayRef yieldInfoArray;
 
 #ifdef USED_IN_CPP_SOURCE
   BridgedYieldInfoArray(llvm::ArrayRef<swift::SILYieldInfo> yields)
@@ -271,7 +271,7 @@ struct BridgedLifetimeDependenceInfo {
 };
 
 struct BridgedLifetimeDependenceInfoArray {
-  BridgedArrayRef lifetimeDependenceInfoArray;
+  BridgedErasedArrayRef lifetimeDependenceInfoArray;
 
 #ifdef USED_IN_CPP_SOURCE
   BridgedLifetimeDependenceInfoArray(
@@ -704,10 +704,9 @@ struct BridgedFunction {
 
   typedef void (* _Nonnull RegisterFn)(BridgedFunction f, void * _Nonnull data, SwiftInt size);
   typedef void (* _Nonnull WriteFn)(BridgedFunction, BridgedOStream, SwiftInt);
-  typedef ParsingError (*_Nonnull ParseFn)(BridgedFunction,
-                                           BridgedStringRef,
+  typedef ParsingError (*_Nonnull ParseFn)(BridgedFunction, BridgedStringRef,
                                            ParseEffectsMode, SwiftInt,
-                                           BridgedArrayRef);
+                                           BridgedErasedArrayRef);
   typedef SwiftInt (* _Nonnull CopyEffectsFn)(BridgedFunction, BridgedFunction);
   typedef EffectInfo (* _Nonnull GetEffectInfoFn)(BridgedFunction, SwiftInt);
   typedef BridgedMemoryBehavior (* _Nonnull GetMemBehaviorFn)(BridgedFunction, bool);
@@ -778,7 +777,7 @@ struct BridgedSubstitutionMap {
 };
 
 struct BridgedTypeArray {
-  BridgedArrayRef typeArray;
+  BridgedErasedArrayRef typeArray;
 
   // Ensure that this struct value type will be indirectly returned on
   // Windows ARM64,
@@ -802,7 +801,7 @@ struct BridgedTypeArray {
 };
 
 struct BridgedSILTypeArray {
-  BridgedArrayRef typeArray;
+  BridgedErasedArrayRef typeArray;
 
 #ifdef USED_IN_CPP_SOURCE
   BridgedSILTypeArray(llvm::ArrayRef<swift::SILType> silTypes)

include/swift/SILOptimizer/OptimizerBridging.h

@@ -140,7 +140,8 @@ struct BridgedPostDomTree {
 struct BridgedUtilities {
   typedef void (* _Nonnull VerifyFunctionFn)(BridgedPassContext, BridgedFunction);
   typedef void (* _Nonnull UpdateBorrowedFromFn)(BridgedPassContext, BridgedFunction);
-  typedef void (* _Nonnull UpdateBorrowedFromPhisFn)(BridgedPassContext, BridgedArrayRef);
+  typedef void (*_Nonnull UpdateBorrowedFromPhisFn)(BridgedPassContext,
+                                                    BridgedErasedArrayRef);
 
   static void registerVerifier(VerifyFunctionFn verifyFunctionFn);
   static void registerBorrowedFromUpdater(UpdateBorrowedFromFn updateBorrowedFromFn,
@@ -257,9 +258,10 @@ struct BridgedPassContext {
   BridgedOwnedString mangleWithDeadArgs(const SwiftInt * _Nullable deadArgs,
                                                             SwiftInt numDeadArgs,
                                                             BridgedFunction function) const;
-  BridgedOwnedString mangleWithClosureArgs(BridgedValueArray closureArgs,
-                                                               BridgedArrayRef closureArgIndices,
-                                                               BridgedFunction applySiteCallee) const;
+  BridgedOwnedString
+  mangleWithClosureArgs(BridgedValueArray closureArgs,
+                        BridgedErasedArrayRef closureArgIndices,
+                        BridgedFunction applySiteCallee) const;
 
   SWIFT_IMPORT_UNSAFE BridgedGlobalVar createGlobalVariable(BridgedStringRef name, BridgedType type,
                                                             bool isPrivate) const;