RtlLocateSupervisorFeature - NtDoc

#ifndef _NTRTL_H
#if (PHNT_VERSION >= PHNT_REDSTONE4)

// msdn
_Ret_maybenull_
_Success_(return != NULL)
NTSYSAPI
PVOID
NTAPI
RtlLocateSupervisorFeature(
    _In_ PXSAVE_AREA_HEADER XStateHeader,
    _In_range_(XSTATE_AVX, MAXIMUM_XSTATE_FEATURES - 1) ULONG FeatureId,
    _Out_opt_ PULONG Length
    );

#endif
#endif
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