VarArg code is all conforming to a C ABI so unlikely to ever change

Author: airspeedswift

stdlib/public/core/VarArgs.swift

@@ -124,7 +124,7 @@ internal typealias _VAInt  = Int32
 ///     The pointer argument is valid only for the duration of the function's
 ///     execution.
 /// - Returns: The return value, if any, of the `body` closure parameter.
-@inlinable // FIXME(sil-serialize-all)
+@inlinable // c-abi
 public func withVaList<R>(_ args: [CVarArg],
   _ body: (CVaListPointer) -> R) -> R {
   let builder = _VaListBuilder()
@@ -135,7 +135,7 @@ public func withVaList<R>(_ args: [CVarArg],
 }
 
 /// Invoke `body` with a C `va_list` argument derived from `builder`.
-@inlinable // FIXME(sil-serialize-all)
+@inlinable // c-abi
 internal func _withVaList<R>(
   _ builder: _VaListBuilder,
   _ body: (CVaListPointer) -> R
@@ -166,7 +166,7 @@ internal func _withVaList<R>(
 ///   pointer.
 /// - Returns: A pointer that can be used with C functions that take a
 ///   `va_list` argument.
-@inlinable // FIXME(sil-serialize-all)
+@inlinable // c-abi
 public func getVaList(_ args: [CVarArg]) -> CVaListPointer {
   let builder = _VaListBuilder()
   for a in args {
@@ -179,7 +179,7 @@ public func getVaList(_ args: [CVarArg]) -> CVaListPointer {
 }
 #endif
 
-@inlinable // FIXME(sil-serialize-all)
+@inlinable // c-abi
 public func _encodeBitsAsWords<T>(_ x: T) -> [Int] {
   let result = [Int](
     repeating: 0,
@@ -201,7 +201,7 @@ public func _encodeBitsAsWords<T>(_ x: T) -> [Int] {
 extension Int : CVarArg {
   /// Transform `self` into a series of machine words that can be
   /// appropriately interpreted by C varargs.
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   public var _cVarArgEncoding: [Int] {
     return _encodeBitsAsWords(self)
   }
@@ -216,14 +216,14 @@ extension Bool : CVarArg {
 extension Int64 : CVarArg, _CVarArgAligned {
   /// Transform `self` into a series of machine words that can be
   /// appropriately interpreted by C varargs.
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   public var _cVarArgEncoding: [Int] {
     return _encodeBitsAsWords(self)
   }
 
   /// Returns the required alignment in bytes of
   /// the value returned by `_cVarArgEncoding`.
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   public var _cVarArgAlignment: Int {
     // FIXME: alignof differs from the ABI alignment on some architectures
     return MemoryLayout.alignment(ofValue: self)
@@ -233,7 +233,7 @@ extension Int64 : CVarArg, _CVarArgAligned {
 extension Int32 : CVarArg {
   /// Transform `self` into a series of machine words that can be
   /// appropriately interpreted by C varargs.
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   public var _cVarArgEncoding: [Int] {
     return _encodeBitsAsWords(_VAInt(self))
   }
@@ -242,7 +242,7 @@ extension Int32 : CVarArg {
 extension Int16 : CVarArg {
   /// Transform `self` into a series of machine words that can be
   /// appropriately interpreted by C varargs.
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   public var _cVarArgEncoding: [Int] {
     return _encodeBitsAsWords(_VAInt(self))
   }
@@ -251,7 +251,7 @@ extension Int16 : CVarArg {
 extension Int8 : CVarArg {
   /// Transform `self` into a series of machine words that can be
   /// appropriately interpreted by C varargs.
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   public var _cVarArgEncoding: [Int] {
     return _encodeBitsAsWords(_VAInt(self))
   }
@@ -261,7 +261,7 @@ extension Int8 : CVarArg {
 extension UInt : CVarArg {
   /// Transform `self` into a series of machine words that can be
   /// appropriately interpreted by C varargs.
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   public var _cVarArgEncoding: [Int] {
     return _encodeBitsAsWords(self)
   }
@@ -270,14 +270,14 @@ extension UInt : CVarArg {
 extension UInt64 : CVarArg, _CVarArgAligned {
   /// Transform `self` into a series of machine words that can be
   /// appropriately interpreted by C varargs.
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   public var _cVarArgEncoding: [Int] {
     return _encodeBitsAsWords(self)
   }
 
   /// Returns the required alignment in bytes of
   /// the value returned by `_cVarArgEncoding`.
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   public var _cVarArgAlignment: Int {
     // FIXME: alignof differs from the ABI alignment on some architectures
     return MemoryLayout.alignment(ofValue: self)
@@ -287,7 +287,7 @@ extension UInt64 : CVarArg, _CVarArgAligned {
 extension UInt32 : CVarArg {
   /// Transform `self` into a series of machine words that can be
   /// appropriately interpreted by C varargs.
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   public var _cVarArgEncoding: [Int] {
     return _encodeBitsAsWords(_VAUInt(self))
   }
@@ -296,7 +296,7 @@ extension UInt32 : CVarArg {
 extension UInt16 : CVarArg {
   /// Transform `self` into a series of machine words that can be
   /// appropriately interpreted by C varargs.
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   public var _cVarArgEncoding: [Int] {
     return _encodeBitsAsWords(_VAUInt(self))
   }
@@ -305,7 +305,7 @@ extension UInt16 : CVarArg {
 extension UInt8 : CVarArg {
   /// Transform `self` into a series of machine words that can be
   /// appropriately interpreted by C varargs.
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   public var _cVarArgEncoding: [Int] {
     return _encodeBitsAsWords(_VAUInt(self))
   }
@@ -314,7 +314,7 @@ extension UInt8 : CVarArg {
 extension OpaquePointer : CVarArg {
   /// Transform `self` into a series of machine words that can be
   /// appropriately interpreted by C varargs.
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   public var _cVarArgEncoding: [Int] {
     return _encodeBitsAsWords(self)
   }
@@ -323,7 +323,7 @@ extension OpaquePointer : CVarArg {
 extension UnsafePointer : CVarArg {
   /// Transform `self` into a series of machine words that can be
   /// appropriately interpreted by C varargs.
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   public var _cVarArgEncoding: [Int] {
     return _encodeBitsAsWords(self)
   }
@@ -332,7 +332,7 @@ extension UnsafePointer : CVarArg {
 extension UnsafeMutablePointer : CVarArg {
   /// Transform `self` into a series of machine words that can be
   /// appropriately interpreted by C varargs.
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   public var _cVarArgEncoding: [Int] {
     return _encodeBitsAsWords(self)
   }
@@ -352,14 +352,14 @@ extension AutoreleasingUnsafeMutablePointer : CVarArg {
 extension Float : _CVarArgPassedAsDouble, _CVarArgAligned {
   /// Transform `self` into a series of machine words that can be
   /// appropriately interpreted by C varargs.
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   public var _cVarArgEncoding: [Int] {
     return _encodeBitsAsWords(Double(self))
   }
 
   /// Returns the required alignment in bytes of
   /// the value returned by `_cVarArgEncoding`.
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   public var _cVarArgAlignment: Int {
     // FIXME: alignof differs from the ABI alignment on some architectures
     return MemoryLayout.alignment(ofValue: Double(self))
@@ -369,14 +369,14 @@ extension Float : _CVarArgPassedAsDouble, _CVarArgAligned {
 extension Double : _CVarArgPassedAsDouble, _CVarArgAligned {
   /// Transform `self` into a series of machine words that can be
   /// appropriately interpreted by C varargs.
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   public var _cVarArgEncoding: [Int] {
     return _encodeBitsAsWords(self)
   }
 
   /// Returns the required alignment in bytes of
   /// the value returned by `_cVarArgEncoding`.
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   public var _cVarArgAlignment: Int {
     // FIXME: alignof differs from the ABI alignment on some architectures
     return MemoryLayout.alignment(ofValue: self)
@@ -388,36 +388,37 @@ extension Double : _CVarArgPassedAsDouble, _CVarArgAligned {
 /// An object that can manage the lifetime of storage backing a
 /// `CVaListPointer`.
 @_fixed_layout // FIXME(sil-serialize-all)
-@usableFromInline // FIXME(sil-serialize-all)
+@_fixed_layout // c-abi
+@usableFromInline // c-abi
 final internal class _VaListBuilder {
 
-  @_fixed_layout // FIXME(sil-serialize-all)
+  @_fixed_layout // c-abi
   @usableFromInline
   internal struct Header {
-    @inlinable // FIXME(sil-serialize-all)
+    @inlinable // c-abi
     internal init() {}
 
-    @usableFromInline // FIXME(sil-serialize-all)
+    @usableFromInline // c-abi
     internal var gp_offset = CUnsignedInt(0)
-    @usableFromInline // FIXME(sil-serialize-all)
+    @usableFromInline // c-abi
     internal var fp_offset =
       CUnsignedInt(_countGPRegisters * MemoryLayout<Int>.stride)
-    @usableFromInline // FIXME(sil-serialize-all)
+    @usableFromInline // c-abi
     internal var overflow_arg_area: UnsafeMutablePointer<Int>?
-    @usableFromInline // FIXME(sil-serialize-all)
+    @usableFromInline // c-abi
     internal var reg_save_area: UnsafeMutablePointer<Int>?
   }
 
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   internal init() {
     // prepare the register save area
     storage = ContiguousArray(repeating: 0, count: _registerSaveWords)
   }
 
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   deinit {}
 
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   internal func append(_ arg: CVarArg) {
     var encoded = arg._cVarArgEncoding
 
@@ -459,7 +460,7 @@ final internal class _VaListBuilder {
 
   }
 
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   internal func va_list() -> CVaListPointer {
     header.reg_save_area = storage._baseAddress
     header.overflow_arg_area
@@ -469,15 +470,15 @@ final internal class _VaListBuilder {
                Builtin.addressof(&self.header)))
   }
 
-  @usableFromInline // FIXME(sil-serialize-all)
+  @usableFromInline // c-abi
   internal var gpRegistersUsed = 0
-  @usableFromInline // FIXME(sil-serialize-all)
+  @usableFromInline // c-abi
   internal var fpRegistersUsed = 0
 
-  @usableFromInline // FIXME(sil-serialize-all)
+  @usableFromInline // c-abi
   final  // Property must be final since it is used by Builtin.addressof.
   internal var header = Header()
-  @usableFromInline // FIXME(sil-serialize-all)
+  @usableFromInline // c-abi
   internal var storage: ContiguousArray<Int>
 }
 
@@ -486,13 +487,14 @@ final internal class _VaListBuilder {
 /// An object that can manage the lifetime of storage backing a
 /// `CVaListPointer`.
 @_fixed_layout // FIXME(sil-serialize-all)
-@usableFromInline // FIXME(sil-serialize-all)
+@_fixed_layout // c-abi
+@usableFromInline // c-abi
 final internal class _VaListBuilder {
 
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   internal init() {}
 
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   internal func append(_ arg: CVarArg) {
     // Write alignment padding if necessary.
     // This is needed on architectures where the ABI alignment of some
@@ -519,7 +521,7 @@ final internal class _VaListBuilder {
   // Marking it inlinable will cause it to resiliently use accessors to
   // project `_VaListBuilder.alignedStorageForEmptyVaLists` as a computed
   // property.
-  @usableFromInline // FIXME(sil-serialize-all)
+  @usableFromInline // c-abi
   internal func va_list() -> CVaListPointer {
     // Use Builtin.addressof to emphasize that we are deliberately escaping this
     // pointer and assuming it is safe to do so.
@@ -532,7 +534,7 @@ final internal class _VaListBuilder {
   // but possibly more aligned than that.
   // FIXME: this should be packaged into a better storage type
 
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   internal func appendWords(_ words: [Int]) {
     let newCount = count + words.count
     if newCount > allocated {
@@ -558,22 +560,22 @@ final internal class _VaListBuilder {
     }
   }
 
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   internal func rawSizeAndAlignment(
     _ wordCount: Int
   ) -> (Builtin.Word, Builtin.Word) {
     return ((wordCount * MemoryLayout<Int>.stride)._builtinWordValue,
       requiredAlignmentInBytes._builtinWordValue)
   }
 
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   internal func allocStorage(wordCount: Int) -> UnsafeMutablePointer<Int> {
     let (rawSize, rawAlignment) = rawSizeAndAlignment(wordCount)
     let rawStorage = Builtin.allocRaw(rawSize, rawAlignment)
     return UnsafeMutablePointer<Int>(rawStorage)
   }
 
-  @usableFromInline // FIXME(sil-serialize-all)
+  @usableFromInline // c-abi
   internal func deallocStorage(
     wordCount: Int,
     storage: UnsafeMutablePointer<Int>
@@ -582,21 +584,21 @@ final internal class _VaListBuilder {
     Builtin.deallocRaw(storage._rawValue, rawSize, rawAlignment)
   }
 
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable // c-abi
   deinit {
     if let allocatedStorage = storage {
       deallocStorage(wordCount: allocated, storage: allocatedStorage)
     }
   }
 
   // FIXME: alignof differs from the ABI alignment on some architectures
-  @usableFromInline // FIXME(sil-serialize-all)
+  @usableFromInline // c-abi
   internal let requiredAlignmentInBytes = MemoryLayout<Double>.alignment
-  @usableFromInline // FIXME(sil-serialize-all)
+  @usableFromInline // c-abi
   internal var count = 0
-  @usableFromInline // FIXME(sil-serialize-all)
+  @usableFromInline // c-abi
   internal var allocated = 0
-  @usableFromInline // FIXME(sil-serialize-all)
+  @usableFromInline // c-abi
   internal var storage: UnsafeMutablePointer<Int>?
 
   internal static var alignedStorageForEmptyVaLists: Double = 0