Developer Guide and Reference

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_xsetbv()

Writes the given value to a specified extended control register.

Syntax

extern void _xsetbv(unsigned int xcr, unsigned __int64 val);
Arguments
xcr
An extended control register to be written. Currently, only the value '
0
' is allowed.
val
Value to be written to the specified extended control register.
Description
This intrinsic writes the given value to the specified extended control register. Currently, the only control register allowed/defined is
(XCR0) XFEATURE_ENABLED_MASK
register. The corresponding constant is defined in the
immintrin.h
file to refer to this register:
#define _XCR_XFEATURE_ENABLED_MASK 0
This intrinsic maps to
XSETBV
instruction.