interlockedexchangeadd-intrinsic-functions.md

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Learn more about: _InterlockedExchangeAdd intrinsic functions	_InterlockedExchangeAdd intrinsic functions	09/02/2019	_InterlockedExchangeAdd64_nf _InterlockedExchangeAdd64_rel _InterlockedExchangeAdd16_rel _InterlockedExchangeAdd_acq _InterlockedExchangeAdd_nf _InterlockedExchangeAdd_rel _InterlockedExchangeAdd8_acq _InterlockedExchangeAdd16_nf _InterlockedExchangeAdd_acq_cpp _InterlockedExchangeAdd64_acq_cpp _InterlockedExchangeAdd16_acq _InterlockedExchangeAdd_HLERelease _InterlockedExchangeAdd64_cpp _InterlockedExchangeAdd64_HLERelease _InterlockedExchangeAdd64_acq _InterlockedExchangeAdd8 _InterlockedExchangeAdd64 _InterlockedExchangeAdd8_nf _InterlockedExchangeAdd16 _InterlockedExchangeAdd64_rel_cpp _InterlockedExchangeAdd_cpp _InterlockedExchangeAdd8_rel _InterlockedExchangeAdd_HLEAcquire _InterlockedExchangeAdd64_HLEAcquire _InterlockedExchangeAdd	_InterlockedExchangeAdd8_nf intrinsic InterlockedExchangeAdd64_acq intrinsic _InterlockedExchangeAdd8_acq intrinsic _InterlockedExchangeAdd64 intrinsic _InterlockedExchangeAdd intrinsic _InterlockedExchangeAdd8_rel intrinsic _InterlockedExchangeAdd_acq intrinsic _InterlockedExchangeAdd_HLEAcquire intrinsic _InterlockedExchangeAdd8 intrinsic _InterlockedExchangeAdd_rel intrinsic _InterlockedExchangeAdd64_HLERelease intrinsic _InterlockedExchangeAdd64_nf intrinsic InterlockedExchangeAdd_rel intrinsic InterlockedExchangeAdd intrinsic _InterlockedExchangeAdd_nf intrinsic _InterlockedExchangeAdd16_rel intrinsic InterlockedExchangeAdd_acq intrinsic _InterlockedExchangeAdd64_HLEAcquire intrinsic _InterlockedExchangeAdd16 intrinsic _InterlockedExchangeAdd64_acq intrinsic InterlockedExchangeAdd64_rel intrinsic _InterlockedExchangeAdd16_acq intrinsic InterlockedExchangeAdd64 intrinsic _InterlockedExchangeAdd_HLERelease intrinsic _InterlockedExchangeAdd16_nf intrinsic _InterlockedExchangeAdd64_rel intrinsic	25809e1f-9c60-4492-9f7c-0fb59c8d13d2

_InterlockedExchangeAdd intrinsic functions

Microsoft Specific

Provide compiler intrinsic support for the Win32 Windows SDK _InterlockedExchangeAdd intrinsic functions function.

Syntax

long _InterlockedExchangeAdd(
   long volatile * Addend,
   long Value
);
long _InterlockedExchangeAdd_acq(
   long volatile * Addend,
   long Value
);
long _InterlockedExchangeAdd_rel(
   long volatile * Addend,
   long Value
);
long _InterlockedExchangeAdd_nf(
   long volatile * Addend,
   long Value
);
long _InterlockedExchangeAdd_HLEAcquire(
   long volatile * Addend,
   long Value
);
long _InterlockedExchangeAdd_HLERelease(
   long volatile * Addend,
   long Value
);
char _InterlockedExchangeAdd8(
   char volatile * Addend,
   char Value
);
char _InterlockedExchangeAdd8_acq(
   char volatile * Addend,
   char Value
);
char _InterlockedExchangeAdd8_rel(
   char volatile * Addend,
   char Value
);
char _InterlockedExchangeAdd8_nf(
   char volatile * Addend,
   char Value
);
short _InterlockedExchangeAdd16(
   short volatile * Addend,
   short Value
);
short _InterlockedExchangeAdd16_acq(
   short volatile * Addend,
   short Value
);
short _InterlockedExchangeAdd16_rel(
   short volatile * Addend,
   short Value
);
short _InterlockedExchangeAdd16_nf(
   short volatile * Addend,
   short Value
);
__int64 _InterlockedExchangeAdd64(
   __int64 volatile * Addend,
   __int64 Value
);
__int64 _InterlockedExchangeAdd64_acq(
   __int64 volatile * Addend,
   __int64 Value
);
__int64 _InterlockedExchangeAdd64_rel(
   __int64 volatile * Addend,
   __int64 Value
);
__int64 _InterlockedExchangeAdd64_nf(
   __int64 volatile * Addend,
   __int64 Value
);
__int64 _InterlockedExchangeAdd64_HLEAcquire(
   __int64 volatile * Addend,
   __int64 Value
);
__int64 _InterlockedExchangeAdd64_HLERelease(
   __int64 volatile * Addend,
   __int64 Value
);

Parameters

Addend
[in, out] The value to be added to; replaced by the result of the addition.

Value
[in] The value to add.

Return value

The return value is the initial value of the variable pointed to by the Addend parameter.

Requirements

Intrinsic	Architecture	Header
_InterlockedExchangeAdd, _InterlockedExchangeAdd8, _InterlockedExchangeAdd16	x86, ARM, x64, ARM64	<intrin.h>
_InterlockedExchangeAdd64	ARM, x64, ARM64	<intrin.h>
_InterlockedExchangeAdd_acq, _InterlockedExchangeAdd_rel, _InterlockedExchangeAdd_nf, _InterlockedExchangeAdd8_acq, _InterlockedExchangeAdd8_rel, _InterlockedExchangeAdd8_nf,_InterlockedExchangeAdd16_acq, _InterlockedExchangeAdd16_rel, _InterlockedExchangeAdd16_nf, _InterlockedExchangeAdd64_acq, _InterlockedExchangeAdd64_rel, _InterlockedExchangeAdd64_nf	ARM, ARM64	<intrin.h>
_InterlockedExchangeAdd_HLEAcquire, _InterlockedExchangeAdd_HLERelease	x86, x64	<immintrin.h>
_InterlockedExchangeAdd64_HLEAcquire, _InterlockedExchangeAdd64_HLErelease	x64	<immintrin.h>

Remarks

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

While the _InterlockedExchangeAdd function operates on 32-bit integer values, _InterlockedExchangeAdd8 operates on 8-bit integer values, _InterlockedExchangeAdd16 operates on 16-bit integer values, and _InterlockedExchangeAdd64 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 intrinsics with an _nf ("no fence") suffix don't act as a memory barrier.

On Intel platforms that support Hardware Lock Elision (HLE) instructions, the intrinsics with _HLEAcquire and _HLERelease suffixes include a hint to the processor that can accelerate performance by eliminating a lock write step in hardware. If these intrinsics are called on platforms that don't support HLE, the hint is ignored.

These routines are only available as intrinsics. They're intrinsic even when /Oi or #pragma intrinsic is used. It isn't possible to use #pragma function on these intrinsics.

Example

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

END Microsoft Specific

See also

Compiler intrinsics
Keywords
Conflicts with the x86 Compiler