SuperFastHash

This string hash function is dependent on StringLength

#define Get16Bits(d) ((((UINT32)(((CONST UINT8*)(d))[1])) << 8) +(UINT32)(((CONST UINT8*)(d))[0]))

UINT32 HashStringSuperFastHashA(_In_ LPCSTR String)
{
	INT Length = (INT)StringLengthA(String);
	UINT32 Hash = Length;
	INT Tmp = 0;

	INT Rem = Length & 3;
	Length >>= 2;

	for (; Length > 0; Length--)
	{
		Hash += Get16Bits(String);
		Tmp = (Get16Bits(String + 2) << 11) ^ Hash;
		Hash = (Hash << 16) ^ Tmp;
#pragma warning( push )
#pragma warning( disable : 6305)
		String += 2 * sizeof(UINT16);
#pragma warning( pop ) 
		Hash += Hash >> 11;
	}

	switch (Rem)
	{
	case 3:
	{
		Hash += Get16Bits(String);
		Hash ^= Hash << 16;
		Hash ^= ((UCHAR)String[sizeof(UINT16)]) << 18;
		Hash += Hash >> 11;
		break;
	}
	case 2:
	{
		Hash += Get16Bits(String);
		Hash ^= Hash << 11;
		Hash ^= Hash >> 17;
		break;
	}
	case 1:
	{
		Hash += (UCHAR)*String;
		Hash ^= Hash << 10;
		Hash += Hash >> 1;
	}
	}

	Hash ^= Hash << 3;
	Hash += Hash >> 5;
	Hash ^= Hash << 4;
	Hash += Hash >> 17;
	Hash ^= Hash << 25;
	Hash += Hash >> 6;

	return Hash;
}

UINT32 HashStringSuperFastHashW(_In_ LPCWSTR String)
{
	INT Length = (INT)StringLengthW(String);
	UINT32 Hash = Length;
	INT Tmp = 0;

	INT Rem = Length & 3;
	Length >>= 2;

	for (; Length > 0; Length--)
	{
		Hash += Get16Bits(String);
		Tmp = (Get16Bits(String + 2) << 11) ^ Hash;
		Hash = (Hash << 16) ^ Tmp;
#pragma warning( push )
#pragma warning( disable : 6305)
		String += 2 * sizeof(UINT16);
#pragma warning( pop ) 
		Hash += Hash >> 11;
	}

	switch (Rem)
	{
	case 3:
	{
		Hash += Get16Bits(String);
		Hash ^= Hash << 16;
		Hash ^= ((UCHAR)String[sizeof(UINT16)]) << 18;
		Hash += Hash >> 11;
		break;
	}
	case 2:
	{
		Hash += Get16Bits(String);
		Hash ^= Hash << 11;
		Hash ^= Hash >> 17;
		break;
	}
	case 1:
	{
		Hash += (UCHAR)*String;
		Hash ^= Hash << 10;
		Hash += Hash >> 1;
	}
	}

	Hash ^= Hash << 3;
	Hash += Hash >> 5;
	Hash ^= Hash << 4;
	Hash += Hash >> 17;
	Hash ^= Hash << 25;
	Hash += Hash >> 6;

	return Hash;
}

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