span.h File Reference

#include <xgboost/base.h>
#include <xgboost/logging.h>
#include <cinttypes>
#include <limits>
#include <iterator>
#include <type_traits>
#include <cstdio>

Include dependency graph for span.h:

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Go to the source code of this file.

Classes
class	xgboost::common::detail::SpanIterator< SpanType, IsConst >
struct	xgboost::common::detail::ExtentValue< Extent, Offset, Count >
struct	xgboost::common::detail::ExtentAsBytesValue< T, Extent >
struct	xgboost::common::detail::IsAllowedExtentConversion< From, To >
struct	xgboost::common::detail::IsAllowedElementTypeConversion< From, To >
struct	xgboost::common::detail::IsSpanOracle< T >
struct	xgboost::common::detail::IsSpanOracle< Span< T, Extent > >
struct	xgboost::common::detail::IsSpan< T >
struct	xgboost::common::detail::Less< T >
struct	xgboost::common::detail::Greater< T >
class	xgboost::common::Span< T, Extent >
	span class implementation, based on ISO++20 span<T>. The interface should be the same. More...

Namespaces
	xgboost
	namespace of xgboost
	xgboost::common
	xgboost::common::detail

Macros
#define	__span_noexcept   noexcept
	span class based on ISO++20 span More...
#define	KERNEL_CHECK(cond)   (XGBOOST_EXPECT((cond), true) ? static_cast<void>(0) : std::terminate())
#define	SPAN_CHECK(cond)   KERNEL_CHECK(cond)
#define	SPAN_LT(lhs, rhs)   SPAN_CHECK((lhs) < (rhs))

Typedefs
using	xgboost::common::detail::ptrdiff_t = typename std::conditional< std::is_same< std::ptrdiff_t, std::int64_t >::value, std::ptrdiff_t, std::int64_t >::type

Enumerations
enum class	xgboost::common::byte : unsigned char

Functions
template<class InputIt1 , class InputIt2 , class Compare = detail::Less<decltype(std::declval<InputIt1>().operator*())>>
XGBOOST_DEVICE bool	xgboost::common::detail::LexicographicalCompare (InputIt1 first1, InputIt1 last1, InputIt2 first2, InputIt2 last2)
template<class T , std::size_t X, class U , std::size_t Y>
XGBOOST_DEVICE bool	xgboost::common::operator== (Span< T, X > l, Span< U, Y > r)
template<class T , std::size_t X, class U , std::size_t Y>
constexpr XGBOOST_DEVICE bool	xgboost::common::operator!= (Span< T, X > l, Span< U, Y > r)
template<class T , std::size_t X, class U , std::size_t Y>
constexpr XGBOOST_DEVICE bool	xgboost::common::operator< (Span< T, X > l, Span< U, Y > r)
template<class T , std::size_t X, class U , std::size_t Y>
constexpr XGBOOST_DEVICE bool	xgboost::common::operator<= (Span< T, X > l, Span< U, Y > r)
template<class T , std::size_t X, class U , std::size_t Y>
constexpr XGBOOST_DEVICE bool	xgboost::common::operator> (Span< T, X > l, Span< U, Y > r)
template<class T , std::size_t X, class U , std::size_t Y>
constexpr XGBOOST_DEVICE bool	xgboost::common::operator>= (Span< T, X > l, Span< U, Y > r)
template<class T , std::size_t E>
XGBOOST_DEVICE auto	xgboost::common::as_bytes (Span< T, E > s) __span_noexcept -> Span< const byte, detail::ExtentAsBytesValue< T, E >::value >
template<class T , std::size_t E>
XGBOOST_DEVICE auto	xgboost::common::as_writable_bytes (Span< T, E > s) __span_noexcept -> Span< byte, detail::ExtentAsBytesValue< T, E >::value >

Variables
constexpr std::size_t	xgboost::common::dynamic_extent = std::numeric_limits<std::size_t>::max()

Macro Definition Documentation

__span_noexcept

#define __span_noexcept   noexcept

span class based on ISO++20 span

Copyright 2018 XGBoost contributors

About NOLINTs in this file:

If we want Span to work with std interface, like range for loop, the naming must be consistent with std, not XGBoost. Also, the interface also conflicts with XGBoost coding style, specifically, the use of ‘explicit’ keyword.

Some of the code is copied from Guidelines Support Library, here is the license:

Copyright (c) 2015 Microsoft Corporation. All rights reserved.

This code is licensed under the MIT License (MIT).

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

The version number 1910 is picked up from GSL.

We might want to use MOODYCAMEL_NOEXCEPT from dmlc/concurrentqueue.h. But there are a lot more definitions in that file would cause warnings/troubles in MSVC 2013. Currently we try to keep the closure of Span as minimal as possible.

There are other workarounds for MSVC, like _Unwrapped, _Verify_range ... Some of these are hidden magics of MSVC and I tried to avoid them. Should any of them become needed, please consult the source code of GSL, and possibly some explanations from this thread:

https://github.com/Microsoft/GSL/pull/664

TODO(trivialfis): Group these MSVC workarounds into a manageable place.

KERNEL_CHECK

#define KERNEL_CHECK

(

cond

)

(XGBOOST_EXPECT((cond), true) ? static_cast<void>(0) : std::terminate())

SPAN_CHECK

#define SPAN_CHECK

(

cond

)

KERNEL_CHECK(cond)

SPAN_LT

#define SPAN_LT	(		lhs,
			rhs
	)		SPAN_CHECK((lhs) < (rhs))