# interlocked\_exchange\_add

### Function

> interlocked\_exchange\_add

### Syntax

> interlocked\_exchange\_add( \*Variable, Expression );

### Parameters

**\[\*Variable (Addend)]**

A reference to a variable (most of the time a global variable) to add the value of the resulting instruction to it.

**\[Expression (Value)]**

The value which is added to the global variable.

### Description

Performs an atomic addition of two values.

### Return value

The function returns the initial value of the `Variable(Addend)` parameter.

### Examples

`Result = interlocked_exchange_add(.my_gloabl_counter, 0x55);`

Adds the value (`0x55`) to the global variable and saves the initial value of the `.my_gloabl_counter` into a local variable named `Result`.

### Remarks

You can also perform the subtraction by addition (using the 2's-complement system).

### Related

[interlocked\_compare\_exchange](https://docs.hyperdbg.org/commands/scripting-language/functions/interlocked/interlocked_compare_exchange)

[interlocked\_increment](https://docs.hyperdbg.org/commands/scripting-language/functions/interlocked/interlocked_increment)

[interlocked\_exchange](https://docs.hyperdbg.org/commands/scripting-language/functions/interlocked/interlocked_exchange)

[interlocked\_decrement](https://docs.hyperdbg.org/commands/scripting-language/functions/interlocked/interlocked_decrement)