UnsignedMultiply128 - NtDoc

#ifndef _NTINTSAFE_H_INCLUDED_
#if WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_APP | WINAPI_PARTITION_SYSTEM | WINAPI_PARTITION_GAMES)
#if defined(_USE_INTRINSIC_MULTIPLY128)
#if !defined(_ARM64EC_)

#define UnsignedMultiply128 _umul128

#endif
#endif
#endif
#endif
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#ifndef _NTINTSAFE_H_INCLUDED_
#if WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_APP | WINAPI_PARTITION_SYSTEM | WINAPI_PARTITION_GAMES)
#if defined(_USE_INTRINSIC_MULTIPLY128)

ULONG64
UnsignedMultiply128(
    _In_ ULONGLONG ullMultiplicand,
    _In_ ULONGLONG ullMultiplier,
    _Out_ _Deref_out_range_(==, ullMultiplicand * ullMultiplier) ULONGLONG* pullResultHigh);

#endif
#endif
#endif
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