_InterlockedIncrement Intrinsic Functions

Article
12/18/2017

The latest version of this topic can be found at _InterlockedIncrement Intrinsic Functions.

Microsoft Specific**

Provide compiler intrinsic support for the Win32 Windows SDK InterlockedIncrement function.

Syntax

long _InterlockedIncrement(  
   long * lpAddend  
);  
long _InterlockedIncrement_acq(  
   long * lpAddend  
);  
long _InterlockedIncrement_rel(  
   long * lpAddend  
);  
long _InterlockedIncrement_nf(  
   long * lpAddend  
);  
short _InterlockedIncrement16(  
   short * lpAddend  
);  
short _InterlockedIncrement16_acq(  
   short * lpAddend  
);  
short _InterlockedIncrement16_rel(  
   short * lpAddend  
);  
short _InterlockedIncrement16_nf (  
   short * lpAddend  
);  
__int64 _InterlockedIncrement64(  
   __int64 * lpAddend  
);  
__int64 _InterlockedIncrement64_acq(  
   __int64 * lpAddend  
);  
__int64 _InterlockedIncrement64_rel(  
   __int64 * lpAddend  
);   
__int64 _InterlockedIncrement64_nf(  
   __int64 * lpAddend  
);

Parameters

[in, out] lpAddend
Pointer to the variable to be incremented.

Return Value

The return value is the resulting incremented value.

Requirements

Intrinsic	Architecture	Header
`_InterlockedIncrement`, `_InterlockedIncrement16`, `_InterlockedIncrement64`	x86, ARM, x64	<intrin.h>
`_InterlockedIncrement_acq`, `_InterlockedIncrement_rel`, `_InterlockedIncrement_nf`, `_InterlockedIncrement16_acq`, `_InterlockedIncrement16_rel`, `_InterlockedIncrement16_nf`, `_InterlockedIncrement64_acq`, `_InterlockedIncrement64_rel`, `_InterlockedIncrement64_nf`	ARM	<intrin.h>

Remarks

There are several variations on _InterlockedIncrement that vary based on the data types they involve and whether processor-specific acquire or release semantics is used.

While the _InterlockedIncrement function operates on 32-bit integer values, _InterlockedIncrement16 operates on 16-bit integer values and _InterlockedIncrement64 operates on 64-bit integer values.

On ARM platforms, use the intrinsics with _acq and _rel suffixes if you need acquire and release semantics, such as at the beginning and end of a critical section. The intrinsic with an _nf ("no fence") suffix does not act as a memory barrier.

The variable pointed to by the lpAddend parameter must be aligned on a 32-bit boundary; otherwise, this function fails on multiprocessor x86 systems and any non-x86 systems. For more information, see align.

The Win32 function is declared in Wdm.h or Ntddk.h.

These routines are only available as intrinsics.

Example

For a sample of how to use _InterlockedIncrement, see _InterlockedDecrement.