# Ada Programming/Libraries/System.Atomic Operations.Integer Arithmetic

< Ada Programming | Libraries

*This language feature has been introduced in Ada 2022.*

System.Atomic Operations.Integer_Arithmetic is a unit of the Predefined Language Environment since Ada 2022.

```
generic
type Atomic_Type is range <> with Atomic;
package System.Atomic_Operations.Integer_Arithmetic
with Pure, Nonblocking is
procedure Atomic_Add (Item : aliased in out Atomic_Type;
Value : Atomic_Type)
with Convention => Intrinsic;
procedure Atomic_Subtract (Item : aliased in out Atomic_Type;
Value : Atomic_Type)
with Convention => Intrinsic;
function Atomic_Fetch_And_Add
(Item : aliased in out Atomic_Type;
Value : Atomic_Type) return Atomic_Type
with Convention => Intrinsic;
function Atomic_Fetch_And_Subtract
(Item : aliased in out Atomic_Type;
Value : Atomic_Type) return Atomic_Type
with Convention => Intrinsic;
function Is_Lock_Free (Item : aliased Atomic_Type) return Boolean
with Convention => Intrinsic;
end System.Atomic_Operations.Integer_Arithmetic;
```

The operations of this package are defined as follows:

```
procedure Atomic_Add (Item : aliased in out Atomic_Type;
Value : Atomic_Type)
with Convention => Intrinsic;
Atomically performs: Item := Item + Value;
procedure Atomic_Subtract (Item : aliased in out Atomic_Type;
Value : Atomic_Type)
with Convention => Intrinsic;
Atomically performs: Item := Item - Value;
function Atomic_Fetch_And_Add
(Item : aliased in out Atomic_Type;
Value : Atomic_Type) return Atomic_Type
with Convention => Intrinsic;
Atomically performs: Tmp := Item; Item := Item + Value; return Tmp;
function Atomic_Fetch_And_Subtract
(Item : aliased in out Atomic_Type;
Value : Atomic_Type) return Atomic_Type
with Convention => Intrinsic;
Atomically performs: Tmp := Item; Item := Item - Value; return Tmp;
```