Merge pull request #84513 from aidan-hall/pack-opt

Optimize Specializations of Variadic Generics by Eliminating Parameter Packs

Author: aidan-hall

SwiftCompilerSources/Sources/AST/Type.swift

@@ -146,6 +146,8 @@ extension TypeProperties {
   public var isExistentialMetatype: Bool { rawType.bridged.isExistentialMetatypeType() }
   public var isDynamicSelf: Bool { rawType.bridged.isDynamicSelf()}
   public var isBox: Bool { rawType.bridged.isBox() }
+  public var isPack: Bool { rawType.bridged.isPack() }
+  public var isSILPack: Bool { rawType.bridged.isSILPack() }
 
   public var canBeClass: Type.TraitResult { rawType.bridged.canBeClass().result }
 
@@ -263,6 +265,14 @@ extension TypeProperties {
   public func checkConformance(to protocol: ProtocolDecl) -> Conformance {
     return Conformance(bridged: rawType.bridged.checkConformance(`protocol`.bridged))
   }
+
+  public var containsSILPackExpansionType: Bool {
+    return rawType.bridged.containsSILPackExpansionType()
+  }
+
+  public var isSILPackElementAddress: Bool {
+    return rawType.bridged.isSILPackElementAddress()
+  }
 }
 
 public struct TypeArray : RandomAccessCollection, CustomReflectable {

SwiftCompilerSources/Sources/Optimizer/FunctionPasses/CMakeLists.txt

@@ -38,4 +38,5 @@ swift_compiler_sources(Optimizer
   StripObjectHeaders.swift
   TempLValueElimination.swift
   TempRValueElimination.swift
+  PackSpecialization.swift
 )

SwiftCompilerSources/Sources/Optimizer/FunctionPasses/ConstantCapturePropagation.swift

@@ -152,8 +152,8 @@ private func specializeClosure(specializedName: String,
   newParams.append(contentsOf: nonConstantArguments.map { partialApply.parameter(for: $0)! })
 
   let isGeneric = newParams.contains { $0.type.hasTypeParameter } ||
-                  callee.convention.results.contains { $0.type.hasTypeParameter() } ||
-                  callee.convention.errorResult?.type.hasTypeParameter() ?? false
+                  callee.convention.results.contains { $0.type.hasTypeParameter } ||
+                  callee.convention.errorResult?.type.hasTypeParameter ?? false
 
   let specializedClosure = context.createSpecializedFunctionDeclaration(from: callee,
                                                                         withName: specializedName,