//===----------------------------------------------------------*- swift -*-===//
//
// This source file is part of the Swift.org open source project
//
// Copyright (c) 2014 - 2015 Apple Inc. and the Swift project authors
// Licensed under Apache License v2.0 with Runtime Library Exception
//
// See http://swift.org/LICENSE.txt for license information
// See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
//
//===----------------------------------------------------------------------===//
///
/// This file contains Swift wrappers for functions defined in the C++ runtime.
///
//===----------------------------------------------------------------------===//

import SwiftShims

//===----------------------------------------------------------------------===//
// Atomics
//===----------------------------------------------------------------------===//

@asmname("swift_stdlib_atomicCompareExchangeStrongPtr")
func _stdlib_atomicCompareExchangeStrongPtrImpl(
  #object: UnsafeMutablePointer<COpaquePointer>,
  #expected: UnsafeMutablePointer<COpaquePointer>,
  #desired: COpaquePointer) -> Bool

/// Atomic compare and exchange of `UnsafeMutablePointer<T>` with sequentially
/// consistent memory ordering.  Precise semantics are defined in C++11 or C11.
///
/// Warning: this operation is extremely tricky to use correctly because of
/// writeback semantics.
///
/// It is best to use it directly on an
/// `UnsafeMutablePointer<UnsafeMutablePointer<T>>` that is known to point
/// directly to the memory where the value is stored.
///
/// In a call like this:
///
/// ::
///
///   _stdlib_atomicCompareExchangeStrongPtr(&foo.property1.property2, ...)
///
/// you need to manually make sure that:
///
/// - all properties in the chain are physical (to make sure that no writeback
///   happens; the compare-and-exchange instruction should operate on on the
///   shared memory); and
///
/// - the shared memory that you are accessing is located inside a heap
///   allocation (a class instance property, a `_HeapBuffer`, a pointer to
///   an `Array` element etc.)
///
/// If the conditions above are not met, the code will still compile, but the
/// compare-and-exchange instruction will operate on the writeback buffer, and
/// you will get a *race* while doing writeback into shared memory.
@transparent
public // @testable
func _stdlib_atomicCompareExchangeStrongPtr<T>(
  #object: UnsafeMutablePointer<UnsafeMutablePointer<T>>,
  #expected: UnsafeMutablePointer<UnsafeMutablePointer<T>>,
  #desired: UnsafeMutablePointer<T>) -> Bool {
  return _stdlib_atomicCompareExchangeStrongPtrImpl(
    object: UnsafeMutablePointer(object),
    expected: UnsafeMutablePointer(expected),
    desired: COpaquePointer(desired))
}

@transparent
public // @testable
func _stdlib_atomicInitializeARCRef(
  #object: UnsafeMutablePointer<AnyObject?>,
  #desired: AnyObject) -> Bool {
  var expected = COpaquePointer()
  let desiredPtr = Unmanaged.passRetained(desired).toOpaque()
  let wonRace = _stdlib_atomicCompareExchangeStrongPtrImpl(
    object: UnsafeMutablePointer(object),
    expected: &expected,
    desired: desiredPtr)
  if !wonRace {
    // Some other thread initialized the value.  Balance the retain that we
    // performed on 'desired'.
    Unmanaged.passUnretained(desired).release()
  }
  return wonRace
}

% for bits in [ 32, 64 ]:

@asmname("swift_stdlib_atomicCompareExchangeStrongUInt${bits}")
func _stdlib_atomicCompareExchangeStrongUInt${bits}(
  #object: UnsafeMutablePointer<UInt${bits}>,
  #expected: UnsafeMutablePointer<UInt${bits}>,
  #desired: UInt${bits}) -> Bool

func _stdlib_atomicCompareExchangeStrongInt${bits}(
  #object: UnsafeMutablePointer<Int${bits}>,
  #expected: UnsafeMutablePointer<Int${bits}>,
  #desired: Int${bits}) -> Bool {
  return _stdlib_atomicCompareExchangeStrongUInt${bits}(
    object: UnsafeMutablePointer(object),
    expected: UnsafeMutablePointer(expected),
    desired: UInt${bits}(bitPattern: desired))
}

@asmname("swift_stdlib_atomicStoreUInt${bits}")
func _swift_stdlib_atomicStoreUInt${bits}(
  #object: UnsafeMutablePointer<UInt${bits}>,
  #desired: UInt${bits})

func _swift_stdlib_atomicStoreInt${bits}(
  #object: UnsafeMutablePointer<Int${bits}>,
  #desired: Int${bits}) {
  return _swift_stdlib_atomicStoreUInt${bits}(
    object: UnsafeMutablePointer(object),
    desired: UInt${bits}(bitPattern: desired))
}

@asmname("swift_stdlib_atomicLoadUInt${bits}")
func _swift_stdlib_atomicLoadUInt${bits}(
  #object: UnsafeMutablePointer<UInt${bits}>) -> UInt${bits}

func _swift_stdlib_atomicLoadInt${bits}(
  #object: UnsafeMutablePointer<Int${bits}>) -> Int${bits} {
  return Int${bits}(bitPattern:
    _swift_stdlib_atomicLoadUInt${bits}(
      object: UnsafeMutablePointer(object)))
}

// Warning: no overflow checking.
@asmname("swift_stdlib_atomicFetchAddUInt${bits}")
func _swift_stdlib_atomicFetchAddUInt${bits}(
  #object: UnsafeMutablePointer<UInt${bits}>,
  #operand: UInt${bits}) -> UInt${bits}

// Warning: no overflow checking.
func _swift_stdlib_atomicFetchAddInt${bits}(
  #object: UnsafeMutablePointer<Int${bits}>,
  #operand: Int${bits}) -> Int${bits} {
  return Int${bits}(bitPattern:
    _swift_stdlib_atomicFetchAddUInt${bits}(
      object: UnsafeMutablePointer(object),
      operand: UInt${bits}(bitPattern: operand)))
}

% end

func _stdlib_atomicCompareExchangeStrongInt(
  #object: UnsafeMutablePointer<Int>,
  #expected: UnsafeMutablePointer<Int>,
  #desired: Int) -> Bool {
#if arch(i386) || arch(arm)
  return _stdlib_atomicCompareExchangeStrongUInt32(
    object: UnsafeMutablePointer(object),
    expected: UnsafeMutablePointer(expected),
    desired: UInt32(bitPattern: Int32(desired)))
#elseif arch(x86_64) || arch(arm64)
  return _stdlib_atomicCompareExchangeStrongUInt64(
    object: UnsafeMutablePointer(object),
    expected: UnsafeMutablePointer(expected),
    desired: UInt64(bitPattern: Int64(desired)))
#endif
}

func _swift_stdlib_atomicStoreInt(
  #object: UnsafeMutablePointer<Int>,
  #desired: Int) {
#if arch(i386) || arch(arm)
  return _swift_stdlib_atomicStoreUInt32(
    object: UnsafeMutablePointer(object),
    desired: UInt32(bitPattern: Int32(desired)))
#elseif arch(x86_64) || arch(arm64)
  return _swift_stdlib_atomicStoreUInt64(
    object: UnsafeMutablePointer(object),
    desired: UInt64(bitPattern: Int64(desired)))
#endif
}

@transparent
public func _swift_stdlib_atomicLoadInt(
  #object: UnsafeMutablePointer<Int>) -> Int {
#if arch(i386) || arch(arm)
  return Int(Int32(bitPattern:
    _swift_stdlib_atomicLoadUInt32(
      object: UnsafeMutablePointer(object))))
#elseif arch(x86_64) || arch(arm64)
  return Int(Int64(bitPattern:
    _swift_stdlib_atomicLoadUInt64(
      object: UnsafeMutablePointer(object))))
#endif
}

@asmname("swift_stdlib_atomicLoadPtr")
func _swift_stdlib_atomicLoadPtrImpl(
  #object: UnsafeMutablePointer<COpaquePointer>
) -> COpaquePointer

@transparent
public // @testable
func _stdlib_atomicLoadARCRef(
  #object: UnsafeMutablePointer<AnyObject?>
) -> AnyObject? {
  let result = _swift_stdlib_atomicLoadPtrImpl(
    object: UnsafeMutablePointer(object))
  if result != nil {
    return Unmanaged<AnyObject>.fromOpaque(result).takeUnretainedValue()
  }
  return nil
}

// Warning: no overflow checking.
public func _swift_stdlib_atomicFetchAddInt(
  #object: UnsafeMutablePointer<Int>,
  #operand: Int) -> Int {
#if arch(i386) || arch(arm)
  return Int(Int32(bitPattern:
    _swift_stdlib_atomicFetchAddUInt32(
      object: UnsafeMutablePointer(object),
      operand: UInt32(bitPattern: Int32(operand)))))
#elseif arch(x86_64) || arch(arm64)
  return Int(Int64(bitPattern:
    _swift_stdlib_atomicFetchAddUInt64(
      object: UnsafeMutablePointer(object),
      operand: UInt64(bitPattern: Int64(operand)))))
#endif
}

public final class _stdlib_AtomicInt {
  var _value: Int

  var _valuePtr: UnsafeMutablePointer<Int> {
    return UnsafeMutablePointer(_getUnsafePointerToStoredProperties(self))
  }

  public init(_ value: Int = 0) {
    _value = value
  }

  public func store(desired: Int) {
    return _swift_stdlib_atomicStoreInt(object: _valuePtr, desired: desired)
  }

  public func load() -> Int {
    return _swift_stdlib_atomicLoadInt(object: _valuePtr)
  }

  public func fetchAndAdd(operand: Int) -> Int {
    return _swift_stdlib_atomicFetchAddInt(object: _valuePtr, operand: operand)
  }

  public func addAndFetch(operand: Int) -> Int {
    return fetchAndAdd(operand) + operand
  }
}

//===----------------------------------------------------------------------===//
// Conversion of primitive types to `String`
//===----------------------------------------------------------------------===//

/// A 32 byte buffer.
struct _Buffer32 {
  var x0: UInt64 = 0
  var x1: UInt64 = 0
  var x2: UInt64 = 0
  var x3: UInt64 = 0
}

/// A 72 byte buffer.
struct _Buffer72 {
  var x0: UInt64 = 0
  var x1: UInt64 = 0
  var x2: UInt64 = 0
  var x3: UInt64 = 0
  var x4: UInt64 = 0
  var x5: UInt64 = 0
  var x6: UInt64 = 0
  var x7: UInt64 = 0
  var x8: UInt64 = 0
}

% for bits in [ 32, 64, 80 ]:

% if bits == 80:
#if arch(i386) || arch(x86_64)
% end

@asmname("swift_float${bits}ToString")
func _float${bits}ToStringImpl(
  buffer: UnsafeMutablePointer<UTF8.CodeUnit>,
  bufferLength: UWord, value: Float${bits}
) -> UWord

func _float${bits}ToString(value: Float${bits}) -> String {
  _sanityCheck(sizeof(_Buffer32.self) == 32)
  _sanityCheck(sizeof(_Buffer72.self) == 72)

  var buffer = _Buffer32()
  return withUnsafeMutablePointer(&buffer) {
    (bufferPtr) in
    let bufferUTF8Ptr = UnsafeMutablePointer<UTF8.CodeUnit>(bufferPtr)
    let actualLength = _float${bits}ToStringImpl(bufferUTF8Ptr, 32, value)
    return String._fromWellFormedCodeUnitSequence(
      UTF8.self,
      input: UnsafeBufferPointer(
        start: bufferUTF8Ptr, count: Int(actualLength)))
  }
}

% if bits == 80:
#endif
% end

% end

@asmname("swift_int64ToString")
func _int64ToStringImpl(
  buffer: UnsafeMutablePointer<UTF8.CodeUnit>,
  bufferLength: UWord, value: Int64,
  radix: Int64, uppercase: Bool
) -> UWord

func _int64ToString(
  value: Int64, radix: Int64 = 10, uppercase: Bool = false
) -> String {
  if radix >= 10 {
    var buffer = _Buffer32()
    return withUnsafeMutablePointer(&buffer) {
      (bufferPtr) in
      let bufferUTF8Ptr = UnsafeMutablePointer<UTF8.CodeUnit>(bufferPtr)
      let actualLength =
        _int64ToStringImpl(bufferUTF8Ptr, 32, value, radix, uppercase)
      return String._fromWellFormedCodeUnitSequence(
        UTF8.self,
        input: UnsafeBufferPointer(
          start: bufferUTF8Ptr, count: Int(actualLength)))
    }
  } else {
    var buffer = _Buffer72()
    return withUnsafeMutablePointer(&buffer) {
      (bufferPtr) in
      let bufferUTF8Ptr = UnsafeMutablePointer<UTF8.CodeUnit>(bufferPtr)
      let actualLength =
        _int64ToStringImpl(bufferUTF8Ptr, 72, value, radix, uppercase)
      return String._fromWellFormedCodeUnitSequence(
        UTF8.self,
        input: UnsafeBufferPointer(
          start: bufferUTF8Ptr, count: Int(actualLength)))
    }
  }
}

@asmname("swift_uint64ToString")
func _uint64ToStringImpl(
  buffer: UnsafeMutablePointer<UTF8.CodeUnit>,
  bufferLength: UWord, value: UInt64, radix: Int64, uppercase: Bool
) -> UWord

public // @testable
func _uint64ToString(
    value: UInt64, radix: Int64 = 10, uppercase: Bool = false
) -> String {
  if radix >= 10 {
    var buffer = _Buffer32()
    return withUnsafeMutablePointer(&buffer) {
      (bufferPtr) in
      let bufferUTF8Ptr = UnsafeMutablePointer<UTF8.CodeUnit>(bufferPtr)
      let actualLength =
        _uint64ToStringImpl(bufferUTF8Ptr, 32, value, radix, uppercase)
      return String._fromWellFormedCodeUnitSequence(
        UTF8.self,
        input: UnsafeBufferPointer(
          start: bufferUTF8Ptr, count: Int(actualLength)))
    }
  } else {
    var buffer = _Buffer72()
    return withUnsafeMutablePointer(&buffer) {
      (bufferPtr) in
      let bufferUTF8Ptr = UnsafeMutablePointer<UTF8.CodeUnit>(bufferPtr)
      let actualLength =
        _uint64ToStringImpl(bufferUTF8Ptr, 72, value, radix, uppercase)
      return String._fromWellFormedCodeUnitSequence(
        UTF8.self,
        input: UnsafeBufferPointer(
          start: bufferUTF8Ptr, count: Int(actualLength)))
    }
  }
}

func _rawPointerToString(value: Builtin.RawPointer) -> String {
  var result = _uint64ToString(
    UInt64(unsafeBitCast(value, UWord.self)), radix: 16, uppercase: false)
  for i in 0..<(2 * sizeof(Builtin.RawPointer) - count(result)) {
    result = "0" + result
  }
  return "0x" + result
}

#if _runtime(_ObjC)
// These classes are derived from `_SwiftNativeNSXXXBase` (through runtime magic),
// which are derived from `NSXXX`.
//
// This allows us to subclass an Objective-C class and use the fast Swift
// memory allocator.
@objc class _SwiftNativeNSArray {}
@objc class _SwiftNativeNSDictionary {}
@objc class _SwiftNativeNSSet {}
@objc class _SwiftNativeNSEnumerator {}

//===----------------------------------------------------------------------===//
// Support for reliable testing of the return-autoreleased optimization
//===----------------------------------------------------------------------===//

@objc internal class _stdlib_ReturnAutoreleasedDummy {
  // Use 'dynamic' to force Objective-C dispatch, which uses the
  // return-autoreleased call sequence.
  @objc dynamic func returnsAutoreleased(x: AnyObject) -> AnyObject {
    return x
  }

  // Use 'dynamic' to prevent this call to be duplicated into other modules.
  @objc dynamic func initializeReturnAutoreleased() {
    // On x86_64 it is sufficient to perform one cycle of return-autorelesed
    // call sequence in order to initialize all required PLT entries.
    self.returnsAutoreleased(self)
  }
}

/// This function ensures that the return-autoreleased optimization works.
///
/// On some platforms (for example, x86_64), the first call to
/// `objc_autoreleaseReturnValue` will always autorelease because it would fail
/// to verify the instruction sequence in the caller.  On x86_64 certain PLT
/// entries would be still pointing to the resolver function, and sniffing
/// the call sequence would fail.
///
/// This code should live in the core stdlib dylib because PLT tables are
/// separate for each dylib.
///
/// Call this function in a fresh autorelease pool.
public func _stdlib_initializeReturnAutoreleased() {
//  _stdlib_initializeReturnAutoreleasedImpl()
#if arch(x86_64)
  _stdlib_ReturnAutoreleasedDummy().initializeReturnAutoreleased()
#endif
}
#endif