Bit manipulation(since C++20)

From cppreference.com

Compiler support
Freestanding and hosted
Language
Standard library
Standard library headers
Named requirements
Feature test macros(C++20)
Language support library
Concepts library(C++20)
Diagnostics library
Memory management library
Metaprogramming library(C++11)
General utilities library
Containers library
Iterators library
Ranges library(C++20)
Algorithms library
Strings library
Text processing library
Numerics library
Date and time library
Input/output library
Filesystem library(C++17)
Concurrency support library(C++11)
Execution control library(C++26)
Technical specifications
Symbols index
External libraries

[edit]

Utilities library

Language support

Type support (basic types, RTTI)

Library feature-test macros(C++20)

Program utilities

Variadic functions

initializer_list

(C++11)

is_constant_evaluated

(C++20)

is_within_lifetime

(C++26)

source_location

(C++20)

Coroutine support(C++20)

Contract support(C++26)

Three-way comparison

three_way_comparablethree_way_comparable_with

(C++20)(C++20)

strong_ordering

(C++20)

weak_ordering

(C++20)

partial_ordering

(C++20)

common_comparison_category

(C++20)

compare_three_way_result

(C++20)

(C++20)

(C++20)

(C++20)

(C++20)

compare_strong_order_fallback

(C++20)

compare_weak_order_fallback

(C++20)

compare_partial_order_fallback

(C++20)

is_eqis_ltis_lteq

(C++20)(C++20)(C++20)

is_neqis_gtis_gteq

(C++20)(C++20)(C++20)

General utilities

Function objects
Bit manipulation(C++20)
C-style bit manipulation(C++26)
bitset
hash (C++11)

Relational operators(deprecated in C++20)

rel_ops::operator!=rel_ops::operator>

rel_ops::operator<=rel_ops::operator>=

Integer comparison functions

cmp_equalcmp_lesscmp_less_than

(C++20)(C++20)(C++20)

cmp_not_equalcmp_greatercmp_greater_than

(C++20)(C++20)(C++20)

in_range

(C++20)

Swap andtype operations

swap
ranges::swap (C++20)
exchange (C++14)
declval (C++11)
to_underlying (C++23)

forward (C++11)
forward_like (C++23)
move (C++11)
move_if_noexcept (C++11)
as_const (C++17)

Common vocabulary types

pair
tuple (C++11)
optional (C++17)
any (C++17)
variant (C++17)

tuple_size (C++11)
tuple_element (C++11)
apply (C++17)
make_from_tuple (C++17)
expected (C++23)

[edit]

Bit manipulation

bit_cast (C++20)
byteswap (C++23)
Integral powers of2
has_single_bit (C++20)
bit_ceil (C++20)
bit_floor (C++20)
bit_width (C++20)
Rotating
rotl (C++20)
rotr (C++20)
Counting
countl_zero (C++20)
countl_one (C++20)
countr_zero (C++20)
countr_one (C++20)
popcount (C++20)
Endian
endian (C++20)

[edit]

Provides several function templates to access, manipulate, and process individual bits and bit sequences.

Defined in header<bit>

Defined in namespacestd

bit_cast

(C++20)

reinterpret the object representation of one type as that of another
(function template)[edit]

byteswap

(C++23)

reverses the bytes in the given integer value
(function template)[edit]

Integral powers of2

has_single_bit

(C++20)

checks if a number is an integral power of2
(function template)[edit]

bit_ceil

(C++20)

finds the smallest integral power of2 not less than the given value
(function template)[edit]

bit_floor

(C++20)

finds the largest integral power of2 not greater than the given value
(function template)[edit]

bit_width

(C++20)

finds the smallest number of bits needed to represent the given value
(function template)[edit]

Rotating

rotl

(C++20)

computes the result of bitwise left-rotation
(function template)[edit]

rotr

(C++20)

computes the result of bitwise right-rotation
(function template)[edit]

Counting

countl_zero

(C++20)

counts the number of consecutive0 bits, starting from the most significant bit
(function template)[edit]

countl_one

(C++20)

counts the number of consecutive1 bits, starting from the most significant bit
(function template)[edit]

countr_zero

(C++20)

counts the number of consecutive0 bits, starting from the least significant bit
(function template)[edit]

countr_one

(C++20)

counts the number of consecutive1 bits, starting from the least significant bit
(function template)[edit]

popcount

(C++20)

counts the number of1 bits in an unsigned integer
(function template)[edit]

Endian

endian

(C++20)

indicates the endianness of scalar types
(enum)[edit]

[edit]Notes

Feature-test macro	Value	Std	Feature
`__cpp_lib_bit_cast`	`201806L`	(C++20)	std::bit_cast
`__cpp_lib_bitops`	`201907L`	(C++20)	Bit operations
`__cpp_lib_int_pow2`	`202002L`	(C++20)	Integral power-of-2 operations
`__cpp_lib_byteswap`	`202110L`	(C++23)	std::byteswap