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enum Atomic::Ordering

Overview

Specifies how memory accesses, including non atomic, are to be reordered around atomics. Follows the C/C++ semantics: https://en.cppreference.com/w/c/atomic/memory_order.

By default atomics use the sequentially consistent ordering, which has the strongest guarantees. If all you need is to increment a counter, a relaxed ordering may be enough. If you need to synchronize access to other memory (e.g. locks) you may try the acquire/release semantics that may be faster on some architectures (e.g. X86) but remember that an acquire must be paired with a release for the ordering to be guaranteed.

The code generation always enforces the selected memory order, even on weak CPU architectures (e.g. ARM32), with the exception of the Relaxed memory order where only the operation itself is atomic.

Defined in:

atomic.cr

Enum Members

Relaxed = 2
Acquire = 4
Release = 5
AcquireRelease = 6
SequentiallyConsistent = 7

Instance Method Summary

Instance methods inherited from struct Enum

&(other : self) : self &, +(other : Int) : self +, -(other : Int) : self -, <=>(other : self) <=>, ==(other : self)
==(other) ==, ^(other : self) : self ^, |(other : self) : self |, ~ : self ~, clone clone, each(& : self -> ) each, hash(hasher) hash, includes?(other : self) : Bool includes?, inspect(io : IO) : Nil inspect, to_f32 : Float32 to_f32, to_f32! : Float32 to_f32!, to_f64 : Float64 to_f64, to_f64! : Float64 to_f64!, to_i : Int32 to_i, to_i128 : Int128 to_i128, to_i128! : Int128 to_i128!, to_i16 : Int16 to_i16, to_i16! : Int16 to_i16!, to_i32 : Int32 to_i32, to_i32! : Int32 to_i32!, to_i64 : Int64 to_i64, to_i64! : Int64 to_i64!, to_i8 : Int8 to_i8, to_i8! : Int8 to_i8!, to_json(json : JSON::Builder) : Nil to_json, to_s(io : IO) : Nil
to_s : String to_s, to_u128 : UInt128 to_u128, to_u128! : UInt128 to_u128!, to_u16 : UInt16 to_u16, to_u16! : UInt16 to_u16!, to_u32 : UInt32 to_u32, to_u32! : UInt32 to_u32!, to_u64 : UInt64 to_u64, to_u64! : UInt64 to_u64!, to_u8 : UInt8 to_u8, to_u8! : UInt8 to_u8!, to_yaml(yaml : YAML::Nodes::Builder) to_yaml, value : Int value

Constructor methods inherited from struct Enum

from_value(value : Int) : self from_value, new(ctx : YAML::ParseContext, node : YAML::Nodes::Node)
new(value : self)
new(pull : JSON::PullParser) : self new, parse(string : String) : self parse

Class methods inherited from struct Enum

each(& : self -> ) each, from_value?(value : Int) : self | Nil from_value?, names : Array(String) names, parse?(string : String) : self | Nil parse?, valid?(value : self) : Bool valid?, values : Array(self) values

Macros inherited from struct Enum

[](*values) [], flags(*values) flags

Instance methods inherited from module Comparable(Enum)

<(other : T) : Bool <, <=(other : T) <=, <=>(other : T) <=>, ==(other : T) ==, >(other : T) : Bool >, >=(other : T) >=, clamp(min, max)
clamp(range : Range) clamp

Instance methods inherited from struct Value

==(other : Log::Metadata::Value)
==(other : JSON::Any)
==(other : YAML::Any)
==(other) ==, dup dup

Instance methods inherited from class Object

! : Bool !, !=(other) !=, !~(other) !~, ==(other) ==, ===(other : JSON::Any)
===(other : YAML::Any)
===(other) ===, =~(other) =~, as(type : Class) as, as?(type : Class) as?, class class, dup dup, hash(hasher)
hash hash, in?(collection : Object) : Bool
in?(*values : Object) : Bool in?, inspect(io : IO) : Nil
inspect : String inspect, is_a?(type : Class) : Bool is_a?, itself itself, nil? : Bool nil?, not_nil!(message)
not_nil! not_nil!, pretty_inspect(width = 79, newline = "\n", indent = 0) : String pretty_inspect, pretty_print(pp : PrettyPrint) : Nil pretty_print, responds_to?(name : Symbol) : Bool responds_to?, tap(&) tap, to_json(io : IO) : Nil
to_json : String to_json, to_pretty_json(indent : String = " ") : String
to_pretty_json(io : IO, indent : String = " ") : Nil to_pretty_json, to_s(io : IO) : Nil
to_s : String to_s, to_yaml(io : IO) : Nil
to_yaml : String to_yaml, try(&) try, unsafe_as(type : T.class) forall T unsafe_as

Class methods inherited from class Object

from_json(string_or_io : String | IO, root : String)
from_json(string_or_io : String | IO) from_json, from_yaml(string_or_io : String | IO) from_yaml

Macros inherited from class Object

class_getter(*names, &block) class_getter, class_getter!(*names) class_getter!, class_getter?(*names, &block) class_getter?, class_property(*names, &block) class_property, class_property!(*names) class_property!, class_property?(*names, &block) class_property?, class_setter(*names) class_setter, def_clone def_clone, def_equals(*fields) def_equals, def_equals_and_hash(*fields) def_equals_and_hash, def_hash(*fields) def_hash, delegate(*methods, to object) delegate, forward_missing_to(delegate) forward_missing_to, getter(*names, &block) getter, getter!(*names) getter!, getter?(*names, &block) getter?, property(*names, &block) property, property!(*names) property!, property?(*names, &block) property?, setter(*names) setter

Instance Method Detail

def acquire?Source

Returns true if this enum value equals Acquire

def acquire_release?Source

Returns true if this enum value equals AcquireRelease

def relaxed?Source

Returns true if this enum value equals Relaxed

def release?Source

Returns true if this enum value equals Release

def sequentially_consistent?Source

Returns true if this enum value equals SequentiallyConsistent

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Licensed under the Apache License, Version 2.0.
https://crystal-lang.org/api/1.19.0/Atomic/Ordering.html