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core.atomic
The atomic module provides basic support for lockfree concurrent programming.
 License:
 Boost License 1.0
 Authors:
 Sean Kelly, Alex Rønne Petersen, Manu Evans
 Source
 core/atomic.d
 enum MemoryOrder: int;

Specifies the memory ordering semantics of an atomic operation.
 raw

Not sequenced. Corresponds to LLVM AtomicOrdering.Monotonic and C++11/C11
memory_order_relaxed
.  acq

Hoistload + hoiststore barrier. Corresponds to LLVM AtomicOrdering.Acquire and C++11/C11
memory_order_acquire
.  rel

Sinkload + sinkstore barrier. Corresponds to LLVM AtomicOrdering.Release and C++11/C11
memory_order_release
.  acq_rel

Acquire + release barrier. Corresponds to LLVM AtomicOrdering.AcquireRelease and C++11/C11
memory_order_acq_rel
.  seq

Fully sequenced (acquire + release). Corresponds to LLVM AtomicOrdering.SequentiallyConsistent and C++11/C11
memory_order_seq_cst
.

pure nothrow @nogc @trusted T atomicLoad(MemoryOrder ms = MemoryOrder.seq, T)(ref const T val)
Constraints: if (!is(T == shared(U), U) && !is(T == shared(inout(U)), U) && !is(T == shared(const(U)), U));
pure nothrow @nogc @trusted T atomicLoad(MemoryOrder ms = MemoryOrder.seq, T)(ref const shared T val)
Constraints: if (!hasUnsharedIndirections!T);
pure nothrow @nogc @trusted TailShared!T atomicLoad(MemoryOrder ms = MemoryOrder.seq, T)(ref const shared T val)
Constraints: if (hasUnsharedIndirections!T); 
Loads 'val' from memory and returns it. The memory barrier specified by 'ms' is applied to the operation, which is fully sequenced by default. Valid memory orders are MemoryOrder.raw, MemoryOrder.acq, and MemoryOrder.seq.
 Parameters:

T val
The target variable.
 Returns:
 The value of 'val'.

pure nothrow @nogc @trusted void atomicStore(MemoryOrder ms = MemoryOrder.seq, T, V)(ref T val, V newval)
Constraints: if (!is(T == shared) && !is(V == shared));
pure nothrow @nogc @trusted void atomicStore(MemoryOrder ms = MemoryOrder.seq, T, V)(ref shared T val, V newval)
Constraints: if (!is(T == class));
pure nothrow @nogc @trusted void atomicStore(MemoryOrder ms = MemoryOrder.seq, T, V)(ref shared T val, shared V newval)
Constraints: if (is(T == class)); 
Writes 'newval' into 'val'. The memory barrier specified by 'ms' is applied to the operation, which is fully sequenced by default. Valid memory orders are MemoryOrder.raw, MemoryOrder.rel, and MemoryOrder.seq.
 Parameters:

T val
The target variable. V newval
The value to store.

pure nothrow @nogc @trusted T atomicFetchAdd(MemoryOrder ms = MemoryOrder.seq, T)(ref T val, size_t mod)
Constraints: if ((__traits(isIntegral, T)  is(T == U*, U)) && !is(T == shared));
pure nothrow @nogc @trusted T atomicFetchAdd(MemoryOrder ms = MemoryOrder.seq, T)(ref shared T val, size_t mod)
Constraints: if (__traits(isIntegral, T)  is(T == U*, U)); 
Atomically adds
mod
to the value referenced byval
and returns the valueval
held previously. This operation is both lockfree and atomic. Parameters:

T val
Reference to the value to modify. size_t mod
The value to add.
 Returns:

The value held previously by
val
.

pure nothrow @nogc @trusted T atomicFetchSub(MemoryOrder ms = MemoryOrder.seq, T)(ref T val, size_t mod)
Constraints: if ((__traits(isIntegral, T)  is(T == U*, U)) && !is(T == shared));
pure nothrow @nogc @trusted T atomicFetchSub(MemoryOrder ms = MemoryOrder.seq, T)(ref shared T val, size_t mod)
Constraints: if (__traits(isIntegral, T)  is(T == U*, U)); 
Atomically subtracts
mod
from the value referenced byval
and returns the valueval
held previously. This operation is both lockfree and atomic. Parameters:

T val
Reference to the value to modify. size_t mod
The value to subtract.
 Returns:

The value held previously by
val
.

pure nothrow @nogc @trusted T atomicExchange(MemoryOrder ms = MemoryOrder.seq, T, V)(T* here, V exchangeWith)
Constraints: if (!is(T == shared) && !is(V == shared));
pure nothrow @nogc @trusted TailShared!T atomicExchange(MemoryOrder ms = MemoryOrder.seq, T, V)(shared(T)* here, V exchangeWith)
Constraints: if (!is(T == class) && !is(T == interface));
pure nothrow @nogc @trusted shared(T) atomicExchange(MemoryOrder ms = MemoryOrder.seq, T, V)(shared(T)* here, shared(V) exchangeWith)
Constraints: if (is(T == class)  is(T == interface)); 
Exchange
exchangeWith
with the memory referenced byhere
. This operation is both lockfree and atomic. Parameters:

T* here
The address of the destination variable. V exchangeWith
The value to exchange.
 Returns:

The value held previously by
here
.
 template cas(MemoryOrder succ = MemoryOrder.seq, MemoryOrder fail = MemoryOrder.seq)

Performs either compareandset or compareandswap (or exchange).
There are two categories of overloads in this template: The first category does a simple compareandset. The comparison value (
ifThis
) is treated as an rvalue.
The second category does a compareandswap (a.k.a. compareandexchange), and expectsifThis
to be a pointer type, where the previous value ofhere
will be written.
This operation is both lockfree and atomic. Parameters:

T* here The address of the destination variable. V2 writeThis The value to store. V1 ifThis The comparison value.
 Returns:
 true if the store occurred, false if not.

pure nothrow @nogc @trusted bool cas(T, V1, V2)(T* here, V1 ifThis, V2 writeThis)
Constraints: if (!is(T == shared) && is(T : V1)); 
Compareandset for nonshared values

pure nothrow @nogc @trusted bool cas(T, V1, V2)(shared(T)* here, V1 ifThis, V2 writeThis)
Constraints: if (!is(T == class) && (is(T : V1)  is(shared(T) : V1))); 
Compareandset for shared value type

pure nothrow @nogc @trusted bool cas(T, V1, V2)(shared(T)* here, shared(V1) ifThis, shared(V2) writeThis)
Constraints: if (is(T == class)); 
Compareandset for
shared
reference type (class
) 
pure nothrow @nogc @trusted bool cas(T, V)(T* here, T* ifThis, V writeThis)
Constraints: if (!is(T == shared) && !is(V == shared)); 
Compareandexchange for non
shared
types 
pure nothrow @nogc @trusted bool cas(T, V1, V2)(shared(T)* here, V1* ifThis, V2 writeThis)
Constraints: if (!is(T == class) && (is(T : V1)  is(shared(T) : V1))); 
Compare and exchange for mixed
shared
ness types 
pure nothrow @nogc @trusted bool cas(T, V)(shared(T)* here, shared(T)* ifThis, shared(V) writeThis)
Constraints: if (is(T == class)); 
Compareandexchange for
class

pure nothrow @nogc @trusted bool casWeak(MemoryOrder succ = MemoryOrder.seq, MemoryOrder fail = MemoryOrder.seq, T, V1, V2)(T* here, V1 ifThis, V2 writeThis)
Constraints: if (!is(T == shared) && is(T : V1));
pure nothrow @nogc @trusted bool casWeak(MemoryOrder succ = MemoryOrder.seq, MemoryOrder fail = MemoryOrder.seq, T, V1, V2)(shared(T)* here, V1 ifThis, V2 writeThis)
Constraints: if (!is(T == class) && (is(T : V1)  is(shared(T) : V1)));
pure nothrow @nogc @trusted bool casWeak(MemoryOrder succ = MemoryOrder.seq, MemoryOrder fail = MemoryOrder.seq, T, V1, V2)(shared(T)* here, shared(V1) ifThis, shared(V2) writeThis)
Constraints: if (is(T == class)); 
Stores 'writeThis' to the memory referenced by 'here' if the value referenced by 'here' is equal to 'ifThis'. The 'weak' version of cas may spuriously fail. It is recommended to use
casWeak
only whencas
would be used in a loop. This operation is both lockfree and atomic. Parameters:

T* here
The address of the destination variable. V2 writeThis
The value to store. V1 ifThis
The comparison value.
 Returns:
 true if the store occurred, false if not.

pure nothrow @nogc @trusted bool casWeak(MemoryOrder succ = MemoryOrder.seq, MemoryOrder fail = MemoryOrder.seq, T, V)(T* here, T* ifThis, V writeThis)
Constraints: if (!is(T == shared(S), S) && !is(V == shared(U), U));
pure nothrow @nogc @trusted bool casWeak(MemoryOrder succ = MemoryOrder.seq, MemoryOrder fail = MemoryOrder.seq, T, V1, V2)(shared(T)* here, V1* ifThis, V2 writeThis)
Constraints: if (!is(T == class) && (is(T : V1)  is(shared(T) : V1)));
pure nothrow @nogc @trusted bool casWeak(MemoryOrder succ = MemoryOrder.seq, MemoryOrder fail = MemoryOrder.seq, T, V)(shared(T)* here, shared(T)* ifThis, shared(V) writeThis)
Constraints: if (is(T == class)); 
Stores 'writeThis' to the memory referenced by 'here' if the value referenced by 'here' is equal to the value referenced by 'ifThis'. The prior value referenced by 'here' is written to
ifThis
and returned to the user. The 'weak' version of cas may spuriously fail. It is recommended to usecasWeak
only whencas
would be used in a loop. This operation is both lockfree and atomic. Parameters:

T* here
The address of the destination variable. V writeThis
The value to store. T* ifThis
The address of the value to compare, and receives the prior value of here
as output.
 Returns:
 true if the store occurred, false if not.
 pure nothrow @nogc @safe void atomicFence(MemoryOrder order = MemoryOrder.seq)();

Inserts a full load/store memory fence (on platforms that need it). This ensures that all loads and stores before a call to this function are executed before any loads and stores after the call.
 pure nothrow @nogc @safe void pause();

Gives a hint to the processor that the calling thread is in a 'spinwait' loop, allowing to more efficiently allocate resources.

pure nothrow @nogc @safe TailShared!T atomicOp(string op, T, V1)(ref shared T val, V1 mod)
Constraints: if (__traits(compiles, mixin("*cast(T*)&val" ~ op ~ "mod"))); 
Performs the binary operation 'op' on val using 'mod' as the modifier.
 Parameters:

T val
The target variable. V1 mod
The modifier to apply.
 Returns:
 The result of the operation.
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Licensed under the Boost License 1.0.
https://dlang.org/phobos/core_atomic.html