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Merged
StephanTLavavej merged 6 commits into from
Dec 5, 2019
Merged

Implement is_constant_evaluated(), more feature-test macros, and LWG issues #353

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70e27df
Fix #332: LWG-3266 to_chars(bool) should be deleted
StephanTLavavej Dec 5, 2019
369ee8f
Fix #70: LWG-3199 istream >> bitset<0> fails
StephanTLavavej Dec 5, 2019
f0d55cf
Fix #335: LWG-3257 Missing feature testing macro update from WG21-P0858
StephanTLavavej Dec 5, 2019
a0af0e5
Fix #339: WG21-P1902 Missing Feature-Test Macros 2017-2019
StephanTLavavej Dec 5, 2019
058172a
Fix #156: WG21-P0595 is_constant_evaluated()
StephanTLavavej Dec 5, 2019
68850f6
Reorder and rewrap yvals_core.h comments.
StephanTLavavej Dec 5, 2019
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11 changes: 8 additions & 3 deletions stl/inc/bitset
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Original file line number Diff line number Diff line change
Expand Up @@ -532,9 +532,14 @@ basic_istream<_Elem, _Tr>& operator>>(basic_istream<_Elem, _Tr>& _Istr, bitset<_
_CATCH_IO_(_Istr_t, _Istr)
}

if (!_Changed) {
_State |= _Istr_t::failbit;
}
constexpr bool _Has_bits = _Bits > 0;

if
_CONSTEXPR_IF(_Has_bits) {
if (!_Changed) {
_State |= _Istr_t::failbit;
}
}

_Istr.setstate(_State);
_Right = bitset<_Bits>(_Str); // convert string and store
Expand Down
2 changes: 2 additions & 0 deletions stl/inc/charconv
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Original file line number Diff line number Diff line change
Expand Up @@ -190,6 +190,8 @@ inline to_chars_result to_chars(char* const _First, char* const _Last, const uns
return _Integer_to_chars(_First, _Last, _Value, _Base);
}

to_chars_result to_chars(char* _First, char* _Last, bool _Value, int _Base = 10) = delete;


// FUNCTION TEMPLATE _Bit_cast
template <class _To, class _From,
Expand Down
8 changes: 8 additions & 0 deletions stl/inc/type_traits
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Original file line number Diff line number Diff line change
Expand Up @@ -1775,6 +1775,14 @@ inline constexpr bool is_nothrow_invocable_r_v =
_Invoke_traits<void, _Callable, _Args...>::template _Is_nothrow_invocable_r<_Rx>::value;
#endif // _HAS_CXX17

#if _HAS_CXX20
#ifdef __cpp_lib_is_constant_evaluated // TRANSITION, VS 2019 16.5 Preview 2
// FUNCTION is_constant_evaluated
_NODISCARD constexpr bool is_constant_evaluated() noexcept {
return __builtin_is_constant_evaluated();
}
#endif // __cpp_lib_is_constant_evaluated
#endif // _HAS_CXX20

// STRUCT TEMPLATE _Weak_types
template <class _Ty, class = void>
Expand Down
219 changes: 118 additions & 101 deletions stl/inc/yvals_core.h
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Original file line number Diff line number Diff line change
Expand Up @@ -18,48 +18,46 @@
#endif // _STL_COMPILER_PREPROCESSOR

#if _STL_COMPILER_PREPROCESSOR
// _HAS_CXX20 directly controls:
// P0020R6 atomic<float>, atomic<double>, atomic<long double>
// P0318R1 unwrap_reference, unwrap_ref_decay
// P0325R4 to_array()
// P0356R5 bind_front()
// P0439R0 enum class memory_order
// P0457R2 starts_with()/ends_with() For basic_string/basic_string_view
// P0458R2 contains() For Ordered And Unordered Associative Containers
// P0463R1 endian
// P0482R6 Library Support For char8_t
// (mbrtoc8 and c8rtomb not yet implemented)
// P0487R1 Fixing operator>>(basic_istream&, CharT*)
// P0550R2 remove_cvref
// P0553R4 <bit> Rotating And Counting Functions
// P0556R3 <bit> ispow2(), ceil2(), floor2(), log2p1()
// (log2p1() is called bit_length() as of D1956)
// P0616R0 Using move() In <numeric>
// P0631R8 <numbers> Math Constants
// P0646R1 list/forward_list remove()/remove_if()/unique() Return size_type
// P0653R2 to_address()
// P0655R1 visit<R>()
// P0758R1 is_nothrow_convertible
// P0768R1 Library Support For The Spaceship Comparison Operator <=>
// (partially implemented)
// P0769R2 shift_left(), shift_right()
// P0811R3 midpoint(), lerp()
// (partially implemented, lerp() not yet constexpr)
// P0887R1 type_identity
// P0896R4 Ranges
// (partially implemented)
// P0898R3 Standard Library Concepts
// P0919R3 Heterogeneous Lookup For Unordered Containers
// P0966R1 string::reserve() Should Not Shrink
// P1209R0 erase_if(), erase()
// P1227R2 Signed std::ssize(), Unsigned span::size()
// (partially implemented)
// P1357R1 is_bounded_array, is_unbounded_array
// P1612R1 Relocating endian To <bit>
// P1651R0 bind_front() Should Not Unwrap reference_wrapper
// P1690R1 Refining Heterogeneous Lookup For Unordered Containers
// P1754R1 Rename Concepts To standard_case
// P????R? directory_entry::clear_cache()
// Implemented unconditionally:
// N3911 void_t
// N4089 Safe Conversions In unique_ptr<T[]>
// N4169 invoke()
// N4258 noexcept Cleanups
// N4259 uncaught_exceptions()
// N4277 Trivially Copyable reference_wrapper
// N4279 insert_or_assign()/try_emplace() For map/unordered_map
// N4280 size(), empty(), data()
// N4366 Precisely Constraining unique_ptr Assignment
// N4387 Improving pair And tuple
// N4389 bool_constant
// N4508 shared_mutex (Untimed)
// N4510 Supporting Incomplete Types In vector/list/forward_list
// P0006R0 Variable Templates For Type Traits (is_same_v, etc.)
// P0007R1 as_const()
// P0013R1 Logical Operator Type Traits (conjunction, etc.)
// P0033R1 Rewording enable_shared_from_this
// P0063R3 C11 Standard Library
// P0074R0 owner_less<>
// P0092R1 <chrono> floor(), ceil(), round(), abs()
// P0340R3 SFINAE-Friendly underlying_type
// P0414R2 shared_ptr<T[]>, shared_ptr<T[N]>
// P0418R2 atomic compare_exchange memory_order Requirements
// P0435R1 Overhauling common_type
// P0497R0 Fixing shared_ptr For Arrays
// P0513R0 Poisoning hash
// P0516R0 Marking shared_future Copying As noexcept
// P0517R0 Constructing future_error From future_errc
// P0548R1 Tweaking common_type And duration
// P0558R1 Resolving atomic<T> Named Base Class Inconsistencies
// P0599R1 noexcept hash
// P0738R2 istream_iterator Cleanup
// P0771R1 noexcept For std::function's Move Constructor
// P0777R1 Avoiding Unnecessary decay
// P0809R0 Comparing Unordered Containers
// P0941R2 Feature-Test Macros
// P0972R0 noexcept For <chrono> zero(), min(), max()
// P1164R1 Making create_directory() Intuitive
// P1902R1 Missing Feature-Test Macros 2017-2019

// _HAS_CXX17 directly controls:
// P0005R4 not_fn()
Expand Down Expand Up @@ -121,63 +119,63 @@
// The non-Standard std::tr1 namespace and TR1-only machinery
// Enforcement of matching allocator value_types

// _HAS_NODISCARD (in vcruntime.h) controls:
// [[nodiscard]] attributes on STL functions

// _HAS_CXX17 and _SILENCE_ALL_CXX17_DEPRECATION_WARNINGS control:
// P0174R2 Deprecating Vestigial Library Parts
// P0521R0 Deprecating shared_ptr::unique()
// P0618R0 Deprecating <codecvt>
// Other C++17 deprecation warnings

// _HAS_CXX20 directly controls:
// P0020R6 atomic<float>, atomic<double>, atomic<long double>
// P0318R1 unwrap_reference, unwrap_ref_decay
// P0325R4 to_array()
// P0356R5 bind_front()
// P0439R0 enum class memory_order
// P0457R2 starts_with()/ends_with() For basic_string/basic_string_view
// P0458R2 contains() For Ordered And Unordered Associative Containers
// P0463R1 endian
// P0482R6 Library Support For char8_t
// (mbrtoc8 and c8rtomb not yet implemented)
// P0487R1 Fixing operator>>(basic_istream&, CharT*)
// P0550R2 remove_cvref
// P0553R4 <bit> Rotating And Counting Functions
// P0556R3 <bit> ispow2(), ceil2(), floor2(), log2p1()
// (log2p1() is called bit_length() as of D1956)
// P0595R2 is_constant_evaluated()
// P0616R0 Using move() In <numeric>
// P0631R8 <numbers> Math Constants
// P0646R1 list/forward_list remove()/remove_if()/unique() Return size_type
// P0653R2 to_address()
// P0655R1 visit<R>()
// P0758R1 is_nothrow_convertible
// P0768R1 Library Support For The Spaceship Comparison Operator <=>
// (partially implemented)
// P0769R2 shift_left(), shift_right()
// P0811R3 midpoint(), lerp()
// (partially implemented, lerp() not yet constexpr)
// P0887R1 type_identity
// P0896R4 Ranges
// (partially implemented)
// P0898R3 Standard Library Concepts
// P0919R3 Heterogeneous Lookup For Unordered Containers
// P0966R1 string::reserve() Should Not Shrink
// P1209R0 erase_if(), erase()
// P1227R2 Signed std::ssize(), Unsigned span::size()
// (partially implemented)
// P1357R1 is_bounded_array, is_unbounded_array
// P1612R1 Relocating endian To <bit>
// P1651R0 bind_front() Should Not Unwrap reference_wrapper
// P1690R1 Refining Heterogeneous Lookup For Unordered Containers
// P1754R1 Rename Concepts To standard_case
// P????R? directory_entry::clear_cache()

// _HAS_CXX20 and _SILENCE_ALL_CXX20_DEPRECATION_WARNINGS control:
// P0767R1 Deprecating is_pod
// Other C++20 deprecation warnings

// Implemented unconditionally:
// N3911 void_t
// N4089 Safe Conversions In unique_ptr<T[]>
// N4169 invoke()
// N4258 noexcept Cleanups
// N4259 uncaught_exceptions()
// N4277 Trivially Copyable reference_wrapper
// N4279 insert_or_assign()/try_emplace() For map/unordered_map
// N4280 size(), empty(), data()
// N4366 Precisely Constraining unique_ptr Assignment
// N4387 Improving pair And tuple
// N4389 bool_constant
// N4508 shared_mutex (Untimed)
// N4510 Supporting Incomplete Types In vector/list/forward_list
// P0006R0 Variable Templates For Type Traits (is_same_v, etc.)
// P0007R1 as_const()
// P0013R1 Logical Operator Type Traits (conjunction, etc.)
// P0033R1 Rewording enable_shared_from_this
// P0063R3 C11 Standard Library
// P0074R0 owner_less<>
// P0092R1 <chrono> floor(), ceil(), round(), abs()
// P0340R3 SFINAE-Friendly underlying_type
// P0414R2 shared_ptr<T[]>, shared_ptr<T[N]>
// P0418R2 atomic compare_exchange memory_order Requirements
// P0435R1 Overhauling common_type
// P0497R0 Fixing shared_ptr For Arrays
// P0513R0 Poisoning hash
// P0516R0 Marking shared_future Copying As noexcept
// P0517R0 Constructing future_error From future_errc
// P0548R1 Tweaking common_type And duration
// P0558R1 Resolving atomic<T> Named Base Class Inconsistencies
// P0599R1 noexcept hash
// P0738R2 istream_iterator Cleanup
// P0771R1 noexcept For std::function's Move Constructor
// P0777R1 Avoiding Unnecessary decay
// P0809R0 Comparing Unordered Containers
// P0941R2 Feature-Test Macros
// P0972R0 noexcept For <chrono> zero(), min(), max()
// P1164R1 Making create_directory() Intuitive

// Parallel Algorithms Notes
// C++ allows an implementation to implement parallel algorithms as calls to the
// serial algorithms. This implementation parallelizes several common algorithm
// calls, but not all.
// C++ allows an implementation to implement parallel algorithms as calls to the serial algorithms.
// This implementation parallelizes several common algorithm calls, but not all.
//
// The following algorithms are parallelized.
// * adjacent_difference
Expand Down Expand Up @@ -222,9 +220,8 @@
//
// The following are not presently parallelized:
//
// No apparent parallelism performance improvement on target hardware; all
// algorithms which merely copy or permute elements with no branches are
// typically memory bandwidth limited.
// No apparent parallelism performance improvement on target hardware; all algorithms which
// merely copy or permute elements with no branches are typically memory bandwidth limited.
// * copy
// * copy_n
// * fill
Expand All @@ -238,17 +235,15 @@
// * shift_right
// * swap_ranges
//
// Confusion over user parallelism requirements exists; likely in the above
// category anyway.
// Confusion over user parallelism requirements exists; likely in the above category anyway.
// * generate
// * generate_n
//
// Effective parallelism suspected to be infeasible.
// * partial_sort
// * partial_sort_copy
//
// Not yet evaluated; parallelism may be implemented in a future release and is
// suspected to be beneficial.
// Not yet evaluated; parallelism may be implemented in a future release and is suspected to be beneficial.
// * copy_if
// * includes
// * inplace_merge
Expand Down Expand Up @@ -288,6 +283,9 @@
#error _STL_WARNING_LEVEL cannot be greater than 4.
#endif // _STL_WARNING_LEVEL > 4

// _HAS_NODISCARD (in vcruntime.h) controls:
// [[nodiscard]] attributes on STL functions

// Controls whether the STL uses "if constexpr" internally
#ifndef _HAS_IF_CONSTEXPR
#ifdef __CUDACC__
Expand Down Expand Up @@ -907,7 +905,7 @@
#if _HAS_CXX17
#define __cpp_lib_any 201606L
#define __cpp_lib_apply 201603L
#define __cpp_lib_array_constexpr 201603L
#define __cpp_lib_array_constexpr 201803L
#define __cpp_lib_atomic_is_always_lock_free 201603L
#define __cpp_lib_boyer_moore_searcher 201603L
#if _HAS_STD_BYTE
Expand Down Expand Up @@ -940,7 +938,7 @@
#define __cpp_lib_sample 201603L
#define __cpp_lib_scoped_lock 201703L
#define __cpp_lib_shared_ptr_weak_type 201606L
#define __cpp_lib_string_view 201606L
#define __cpp_lib_string_view 201803L
#define __cpp_lib_to_chars 201611L
#define __cpp_lib_variant 201606L
#else // _HAS_CXX17
Expand All @@ -949,14 +947,18 @@

// C++20
#if _HAS_CXX20
#define __cpp_lib_bind_front 201907L
#define __cpp_lib_atomic_float 201711L
#define __cpp_lib_bind_front 201907L

#if defined(__clang__) || defined(__EDG__)
#define __cpp_lib_bitops 201907L
#else // ^^^ Clang and EDG / MSVC vvv
// a future MSVC update will embed CPU feature detection into <bit> intrinsics
// TRANSITION, VSO-1020212
#endif // defined(__clang__) || defined(__EDG__)

#define __cpp_lib_bounded_array_traits 201902L

#ifdef __cpp_char8_t
#define __cpp_lib_char8_t 201811L
#endif // __cpp_char8_t
Expand All @@ -973,9 +975,24 @@
#define __cpp_lib_endian 201907L
#define __cpp_lib_erase_if 201811L
#define __cpp_lib_generic_unordered_lookup 201811L
#define __cpp_lib_list_remove_return_type 201806L
#define __cpp_lib_math_constants 201907L
#define __cpp_lib_to_array 201907L
#define __cpp_lib_int_pow2 201806L

#if defined(__clang__) || defined(__EDG__) \
|| (defined(_MSC_VER) && _MSC_VER >= 1925 && !(_MSC_FULL_VER == 192528318 && _MSC_BUILD == 97))
#define __cpp_lib_is_constant_evaluated 201811L
#endif // TRANSITION, VS 2019 16.5 Preview 2 and toolset update

#define __cpp_lib_list_remove_return_type 201806L
#define __cpp_lib_math_constants 201907L
#define __cpp_lib_nothrow_convertible 201806L
#define __cpp_lib_remove_cvref 201711L
#define __cpp_lib_shift 201806L
#define __cpp_lib_ssize 201902L
#define __cpp_lib_starts_ends_with 201711L
#define __cpp_lib_to_address 201711L
#define __cpp_lib_to_array 201907L
#define __cpp_lib_type_identity 201806L
#define __cpp_lib_unwrap_ref 201811L
#endif // _HAS_CXX20

// EXPERIMENTAL
Expand Down