Merge pull request swiftlang#36407 from slavapestov/tjw-regression-from-sr11153

Add regression tests for fixed crashers

Author: slavapestov

validation-test/compiler_crashers_2_fixed/Inputs/sr11153_2_other.swift

@@ -0,0 +1,17 @@
+protocol Snapshotting {
+    associatedtype NativeType: NativeInserting where NativeType.SnapshotType == Self
+    associatedtype ChangeType: SnapshotChange where ChangeType.SnapshotType == Self
+}
+
+protocol NativeInserting {
+    associatedtype SnapshotType : Snapshotting where SnapshotType.NativeType == Self
+}
+
+protocol SnapshotProperties : OptionSet where RawValue == Int {
+    static var all: Self { get }
+}
+
+protocol SnapshotChange {
+    associatedtype SnapshotType : Snapshotting where SnapshotType.ChangeType == Self
+    associatedtype PropertiesType : SnapshotProperties
+}

validation-test/compiler_crashers_2_fixed/sr11153_2.swift

@@ -0,0 +1,15 @@
+// RUN: %target-swift-frontend -emit-ir -primary-file %S/Inputs/sr11153_2_other.swift -primary-file %s
+// RUN: %target-swift-frontend -emit-ir %S/Inputs/sr11153_2_other.swift %s
+
+class WatchRegistry {
+    func single<S: Snapshotting>(objectType: S.Type) throws -> Watch<S>
+    {
+        return try Watch<S>.singleObject(objectType: S.self, properties: S.ChangeType.PropertiesType.all)
+    }
+}
+
+class Watch<SnapshotType : Snapshotting> {
+    static func singleObject(objectType: SnapshotType.Type, properties: SnapshotType.ChangeType.PropertiesType) throws -> Watch<SnapshotType> {
+        fatalError()
+    }
+}

validation-test/compiler_crashers_2_fixed/sr4203.swift

@@ -0,0 +1,43 @@
+// RUN: %target-swift-frontend -emit-ir %s
+
+public protocol SomeProto {
+    associatedtype ThingType
+	func getThing() -> ThingType
+}
+
+public protocol SpecialThing: RandomAccessCollection {
+}
+
+public protocol Castable {
+	associatedtype Source
+	static func cast(from: Source) -> Self
+}
+
+public struct ThingGetter<P: SomeProto, T> {
+	public let thing: P
+}
+
+extension ThingGetter where P.ThingType: SpecialThing, T: Castable, P.ThingType.Iterator.Element == T.Source {
+
+	public func getView() -> ThingView {
+		return ThingView(thing: thing.getThing())
+	}
+	
+	public struct ThingView: SpecialThing {
+		let thing: P.ThingType
+
+		public typealias Index = P.ThingType.Index
+		public var startIndex: Index    { return thing.startIndex }
+		public var endIndex:   Index    { return thing.startIndex }
+		public var count: Int           { return thing.count }
+		public func index(after i: Index) -> Index {
+			return thing.index(after: i)
+		}
+		public func index(before i: Index) -> Index {
+			return thing.index(before: i)
+		}
+		public subscript(i: Index) -> T {
+			return T.cast(from: thing[i])
+		}
+	}
+}