dolphin/Externals/WIL/include/wil/wistd_functional.h
2020-02-09 19:01:44 +01:00

544 lines
18 KiB
C++

// -*- C++ -*-
//===------------------------ functional ----------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// STL common functionality
//
// Some aspects of STL are core language concepts that should be used from all C++ code, regardless
// of whether exceptions are enabled in the component. Common library code that expects to be used
// from exception-free components want these concepts, but including STL headers directly introduces
// friction as it requires components not using STL to declare their STL version. Doing so creates
// ambiguity around whether STL use is safe in a particular component and implicitly brings in
// a long list of headers (including <new>) which can create further ambiguity around throwing new
// support (some routines pulled in may expect it). Secondarily, pulling in these headers also has
// the potential to create naming conflicts or other implied dependencies.
//
// To promote the use of these core language concepts outside of STL-based binaries, this file is
// selectively pulling those concepts *directly* from corresponding STL headers. The corresponding
// "std::" namespace STL functions and types should be preferred over these in code that is bound to
// STL. The implementation and naming of all functions are taken directly from STL, instead using
// "wistd" (Windows Implementation std) as the namespace.
//
// Routines in this namespace should always be considered a reflection of the *current* STL implementation
// of those routines. Updates from STL should be taken, but no "bugs" should be fixed here.
//
// New, exception-based code should not use this namespace, but instead should prefer the std:: implementation.
// Only code that is not exception-based and libraries that expect to be utilized across both exception
// and non-exception based code should utilize this functionality.
#ifndef _WISTD_FUNCTIONAL_H_
#define _WISTD_FUNCTIONAL_H_
// DO NOT add *any* additional includes to this file -- there should be no dependencies from its usage
#include "wistd_memory.h"
#include <intrin.h> // For __fastfail
#include <new.h> // For placement new
#if !defined(__WI_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
#pragma GCC system_header
#endif
#pragma warning(push)
#pragma warning(disable: 4324)
/// @cond
namespace wistd // ("Windows Implementation" std)
{
// wistd::function
//
// All of the code below is in direct support of wistd::function. This class is identical to std::function
// with the following exceptions:
//
// 1) It never allocates and is safe to use from exception-free code (custom allocators are not supported)
// 2) It's slightly bigger on the stack (64 bytes, rather than 24 for 32bit)
// 3) There is an explicit static-assert if a lambda becomes too large to hold in the internal buffer (rather than an allocation)
template <class _Ret>
struct __invoke_void_return_wrapper
{
#ifndef __WI_LIBCPP_CXX03_LANG
template <class ..._Args>
static _Ret __call(_Args&&... __args) {
return __invoke(wistd::forward<_Args>(__args)...);
}
#else
template <class _Fn>
static _Ret __call(_Fn __f) {
return __invoke(__f);
}
template <class _Fn, class _A0>
static _Ret __call(_Fn __f, _A0& __a0) {
return __invoke(__f, __a0);
}
template <class _Fn, class _A0, class _A1>
static _Ret __call(_Fn __f, _A0& __a0, _A1& __a1) {
return __invoke(__f, __a0, __a1);
}
template <class _Fn, class _A0, class _A1, class _A2>
static _Ret __call(_Fn __f, _A0& __a0, _A1& __a1, _A2& __a2){
return __invoke(__f, __a0, __a1, __a2);
}
#endif
};
template <>
struct __invoke_void_return_wrapper<void>
{
#ifndef __WI_LIBCPP_CXX03_LANG
template <class ..._Args>
static void __call(_Args&&... __args) {
(void)__invoke(wistd::forward<_Args>(__args)...);
}
#else
template <class _Fn>
static void __call(_Fn __f) {
__invoke(__f);
}
template <class _Fn, class _A0>
static void __call(_Fn __f, _A0& __a0) {
__invoke(__f, __a0);
}
template <class _Fn, class _A0, class _A1>
static void __call(_Fn __f, _A0& __a0, _A1& __a1) {
__invoke(__f, __a0, __a1);
}
template <class _Fn, class _A0, class _A1, class _A2>
static void __call(_Fn __f, _A0& __a0, _A1& __a1, _A2& __a2) {
__invoke(__f, __a0, __a1, __a2);
}
#endif
};
////////////////////////////////////////////////////////////////////////////////
// FUNCTION
//==============================================================================
// bad_function_call
__WI_LIBCPP_NORETURN inline __WI_LIBCPP_INLINE_VISIBILITY
void __throw_bad_function_call()
{
__fastfail(7); // FAST_FAIL_FATAL_APP_EXIT
}
template<class _Fp> class __WI_LIBCPP_TEMPLATE_VIS function; // undefined
namespace __function
{
template<class _Rp>
struct __maybe_derive_from_unary_function
{
};
template<class _Rp, class _A1>
struct __maybe_derive_from_unary_function<_Rp(_A1)>
: public unary_function<_A1, _Rp>
{
};
template<class _Rp>
struct __maybe_derive_from_binary_function
{
};
template<class _Rp, class _A1, class _A2>
struct __maybe_derive_from_binary_function<_Rp(_A1, _A2)>
: public binary_function<_A1, _A2, _Rp>
{
};
template <class _Fp>
__WI_LIBCPP_INLINE_VISIBILITY
bool __not_null(_Fp const&) { return true; }
template <class _Fp>
__WI_LIBCPP_INLINE_VISIBILITY
bool __not_null(_Fp* __ptr) { return __ptr; }
template <class _Ret, class _Class>
__WI_LIBCPP_INLINE_VISIBILITY
bool __not_null(_Ret _Class::*__ptr) { return __ptr; }
template <class _Fp>
__WI_LIBCPP_INLINE_VISIBILITY
bool __not_null(function<_Fp> const& __f) { return !!__f; }
} // namespace __function
#ifndef __WI_LIBCPP_CXX03_LANG
namespace __function {
template<class _Fp> class __base;
template<class _Rp, class ..._ArgTypes>
class __base<_Rp(_ArgTypes...)>
{
__base(const __base&);
__base& operator=(const __base&);
public:
__WI_LIBCPP_INLINE_VISIBILITY __base() {}
__WI_LIBCPP_INLINE_VISIBILITY virtual ~__base() {}
virtual void __clone(__base*) const = 0;
virtual void __move(__base*) = 0;
virtual void destroy() WI_NOEXCEPT = 0;
virtual _Rp operator()(_ArgTypes&& ...) = 0;
};
template<class _FD, class _FB> class __func;
template<class _Fp, class _Rp, class ..._ArgTypes>
class __func<_Fp, _Rp(_ArgTypes...)>
: public __base<_Rp(_ArgTypes...)>
{
_Fp __f_;
public:
__WI_LIBCPP_INLINE_VISIBILITY
explicit __func(_Fp&& __f)
: __f_(wistd::move(__f)) {}
__WI_LIBCPP_INLINE_VISIBILITY
explicit __func(const _Fp& __f)
: __f_(__f) {}
virtual void __clone(__base<_Rp(_ArgTypes...)>*) const;
virtual void __move(__base<_Rp(_ArgTypes...)>*);
virtual void destroy() WI_NOEXCEPT;
virtual _Rp operator()(_ArgTypes&& ... __arg);
};
template<class _Fp, class _Rp, class ..._ArgTypes>
void
__func<_Fp, _Rp(_ArgTypes...)>::__clone(__base<_Rp(_ArgTypes...)>* __p) const
{
::new (__p) __func(__f_);
}
template<class _Fp, class _Rp, class ..._ArgTypes>
void
__func<_Fp, _Rp(_ArgTypes...)>::__move(__base<_Rp(_ArgTypes...)>* __p)
{
::new (__p) __func(wistd::move(__f_));
}
template<class _Fp, class _Rp, class ..._ArgTypes>
void
__func<_Fp, _Rp(_ArgTypes...)>::destroy() WI_NOEXCEPT
{
__f_.~_Fp();
}
template<class _Fp, class _Rp, class ..._ArgTypes>
_Rp
__func<_Fp, _Rp(_ArgTypes...)>::operator()(_ArgTypes&& ... __arg)
{
typedef __invoke_void_return_wrapper<_Rp> _Invoker;
return _Invoker::__call(__f_, wistd::forward<_ArgTypes>(__arg)...);
}
} // __function
template<class _Rp, class ..._ArgTypes>
class __WI_LIBCPP_TEMPLATE_VIS function<_Rp(_ArgTypes...)>
: public __function::__maybe_derive_from_unary_function<_Rp(_ArgTypes...)>,
public __function::__maybe_derive_from_binary_function<_Rp(_ArgTypes...)>
{
// 'wistd::function' is most similar to 'inplace_function' in that it _only_ permits holding function objects
// that can fit within its internal buffer. Therefore, we expand this size to accommodate space for at least 12
// pointers (__base vtable takes an additional one).
static constexpr size_t __buffer_size = 13 * sizeof(void*);
typedef __function::__base<_Rp(_ArgTypes...)> __base;
__WI_LIBCPP_SUPPRESS_NONINIT_ANALYSIS
typename aligned_storage<__buffer_size>::type __buf_;
__base* __f_;
__WI_LIBCPP_NO_CFI static __base *__as_base(void *p) {
return reinterpret_cast<__base*>(p);
}
template <class _Fp, bool>
struct __callable_imp
{
static const bool value = is_same<void, _Rp>::value ||
is_convertible<typename __invoke_of<_Fp&, _ArgTypes...>::type,
_Rp>::value;
};
template <class _Fp>
struct __callable_imp<_Fp, false>
{
static const bool value = false;
};
template <class _Fp>
struct __callable
{
static const bool value = __callable_imp<_Fp, __lazy_and<
integral_constant<bool, !is_same<__uncvref_t<_Fp>, function>::value>,
__invokable<_Fp&, _ArgTypes...>
>::value>::value;
};
template <class _Fp>
using _EnableIfCallable = typename enable_if<__callable<_Fp>::value>::type;
public:
typedef _Rp result_type;
// construct/copy/destroy:
__WI_LIBCPP_INLINE_VISIBILITY __WI_LIBCPP_SUPPRESS_NONINIT_ANALYSIS
function() WI_NOEXCEPT : __f_(0) {}
__WI_LIBCPP_INLINE_VISIBILITY
function(nullptr_t) WI_NOEXCEPT : __f_(0) {}
function(const function&);
function(function&&);
template<class _Fp, class = _EnableIfCallable<_Fp>>
function(_Fp);
function& operator=(const function&);
function& operator=(function&&);
function& operator=(nullptr_t) WI_NOEXCEPT;
template<class _Fp, class = _EnableIfCallable<_Fp>>
function& operator=(_Fp&&);
~function();
// function modifiers:
void swap(function&);
// function capacity:
__WI_LIBCPP_INLINE_VISIBILITY
__WI_LIBCPP_EXPLICIT operator bool() const WI_NOEXCEPT {return __f_;}
// deleted overloads close possible hole in the type system
template<class _R2, class... _ArgTypes2>
bool operator==(const function<_R2(_ArgTypes2...)>&) const = delete;
template<class _R2, class... _ArgTypes2>
bool operator!=(const function<_R2(_ArgTypes2...)>&) const = delete;
public:
// function invocation:
_Rp operator()(_ArgTypes...) const;
// NOTE: type_info is very compiler specific, and on top of that, we're operating in a namespace other than
// 'std' so all functions requiring RTTI have been removed
};
template<class _Rp, class ..._ArgTypes>
__WI_LIBCPP_SUPPRESS_NONINIT_ANALYSIS
function<_Rp(_ArgTypes...)>::function(const function& __f)
{
if (__f.__f_ == 0)
__f_ = 0;
else
{
__f_ = __as_base(&__buf_);
__f.__f_->__clone(__f_);
}
}
template<class _Rp, class ..._ArgTypes>
__WI_LIBCPP_SUPPRESS_NONINIT_ANALYSIS __WI_LIBCPP_SUPPRESS_NOEXCEPT_ANALYSIS
function<_Rp(_ArgTypes...)>::function(function&& __f)
{
if (__f.__f_ == 0)
__f_ = 0;
else
{
__f_ = __as_base(&__buf_);
__f.__f_->__move(__f_);
__f.__f_->destroy();
__f.__f_ = 0;
}
}
template<class _Rp, class ..._ArgTypes>
template <class _Fp, class>
__WI_LIBCPP_SUPPRESS_NONINIT_ANALYSIS
function<_Rp(_ArgTypes...)>::function(_Fp __f)
: __f_(0)
{
if (__function::__not_null(__f))
{
typedef __function::__func<_Fp, _Rp(_ArgTypes...)> _FF;
static_assert(sizeof(_FF) <= sizeof(__buf_),
"The sizeof(wistd::function) has grown too large for the reserved buffer (12 pointers). Refactor to reduce size of the capture.");
__f_ = ::new((void*)&__buf_) _FF(wistd::move(__f));
}
}
template<class _Rp, class ..._ArgTypes>
function<_Rp(_ArgTypes...)>&
function<_Rp(_ArgTypes...)>::operator=(const function& __f)
{
*this = nullptr;
if (__f.__f_)
{
__f_ = __as_base(&__buf_);
__f.__f_->__clone(__f_);
}
return *this;
}
template<class _Rp, class ..._ArgTypes>
function<_Rp(_ArgTypes...)>&
function<_Rp(_ArgTypes...)>::operator=(function&& __f)
{
*this = nullptr;
if (__f.__f_)
{
__f_ = __as_base(&__buf_);
__f.__f_->__move(__f_);
__f.__f_->destroy();
__f.__f_ = 0;
}
return *this;
}
template<class _Rp, class ..._ArgTypes>
function<_Rp(_ArgTypes...)>&
function<_Rp(_ArgTypes...)>::operator=(nullptr_t) WI_NOEXCEPT
{
__base* __t = __f_;
__f_ = 0;
if (__t)
__t->destroy();
return *this;
}
template<class _Rp, class ..._ArgTypes>
template <class _Fp, class>
function<_Rp(_ArgTypes...)>&
function<_Rp(_ArgTypes...)>::operator=(_Fp&& __f)
{
*this = nullptr;
if (__function::__not_null(__f))
{
typedef __function::__func<typename decay<_Fp>::type, _Rp(_ArgTypes...)> _FF;
static_assert(sizeof(_FF) <= sizeof(__buf_),
"The sizeof(wistd::function) has grown too large for the reserved buffer (12 pointers). Refactor to reduce size of the capture.");
__f_ = ::new((void*)&__buf_) _FF(wistd::move(__f));
}
return *this;
}
template<class _Rp, class ..._ArgTypes>
function<_Rp(_ArgTypes...)>::~function()
{
if (__f_)
__f_->destroy();
}
template<class _Rp, class ..._ArgTypes>
void
function<_Rp(_ArgTypes...)>::swap(function& __f)
{
if (wistd::addressof(__f) == this)
return;
if (__f_ && __f.__f_)
{
typename aligned_storage<sizeof(__buf_)>::type __tempbuf;
__base* __t = __as_base(&__tempbuf);
__f_->__move(__t);
__f_->destroy();
__f_ = 0;
__f.__f_->__move(__as_base(&__buf_));
__f.__f_->destroy();
__f.__f_ = 0;
__f_ = __as_base(&__buf_);
__t->__move(__as_base(&__f.__buf_));
__t->destroy();
__f.__f_ = __as_base(&__f.__buf_);
}
else if (__f_)
{
__f_->__move(__as_base(&__f.__buf_));
__f_->destroy();
__f_ = 0;
__f.__f_ = __as_base(&__f.__buf_);
}
else if (__f.__f_)
{
__f.__f_->__move(__as_base(&__buf_));
__f.__f_->destroy();
__f.__f_ = 0;
__f_ = __as_base(&__buf_);
}
}
template<class _Rp, class ..._ArgTypes>
_Rp
function<_Rp(_ArgTypes...)>::operator()(_ArgTypes... __arg) const
{
if (__f_ == 0)
__throw_bad_function_call();
return (*__f_)(wistd::forward<_ArgTypes>(__arg)...);
}
template <class _Rp, class... _ArgTypes>
inline __WI_LIBCPP_INLINE_VISIBILITY
bool
operator==(const function<_Rp(_ArgTypes...)>& __f, nullptr_t) WI_NOEXCEPT {return !__f;}
template <class _Rp, class... _ArgTypes>
inline __WI_LIBCPP_INLINE_VISIBILITY
bool
operator==(nullptr_t, const function<_Rp(_ArgTypes...)>& __f) WI_NOEXCEPT {return !__f;}
template <class _Rp, class... _ArgTypes>
inline __WI_LIBCPP_INLINE_VISIBILITY
bool
operator!=(const function<_Rp(_ArgTypes...)>& __f, nullptr_t) WI_NOEXCEPT {return (bool)__f;}
template <class _Rp, class... _ArgTypes>
inline __WI_LIBCPP_INLINE_VISIBILITY
bool
operator!=(nullptr_t, const function<_Rp(_ArgTypes...)>& __f) WI_NOEXCEPT {return (bool)__f;}
// Provide both 'swap_wil' and 'swap' since we now have two ADL scenarios that we need to work
template <class _Rp, class... _ArgTypes>
inline __WI_LIBCPP_INLINE_VISIBILITY
void
swap(function<_Rp(_ArgTypes...)>& __x, function<_Rp(_ArgTypes...)>& __y)
{return __x.swap(__y);}
template <class _Rp, class... _ArgTypes>
inline __WI_LIBCPP_INLINE_VISIBILITY
void
swap_wil(function<_Rp(_ArgTypes...)>& __x, function<_Rp(_ArgTypes...)>& __y)
{return __x.swap(__y);}
// std::invoke
template <class _Fn, class ..._Args>
typename __invoke_of<_Fn, _Args...>::type
invoke(_Fn&& __f, _Args&&... __args)
__WI_NOEXCEPT_((__nothrow_invokable<_Fn, _Args...>::value))
{
return wistd::__invoke(wistd::forward<_Fn>(__f), wistd::forward<_Args>(__args)...);
}
#else // __WI_LIBCPP_CXX03_LANG
#error wistd::function and wistd::invoke not implemented for pre-C++11
#endif
}
/// @endcond
#pragma warning(pop)
#endif // _WISTD_FUNCTIONAL_H_