Crypt-Komihash

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lib/Crypt/komihash.h  view on Meta::CPAN

		#warning KOMIHASH: cannot determine endianness, assuming little-endian.

		#define KOMIHASH_LITTLE_ENDIAN 1

	#endif // defined( __BIG_ENDIAN__ )
#endif // !defined( KOMIHASH_LITTLE_ENDIAN )

/**
 * @def KOMIHASH_GCC_BUILTINS
 * @brief Macro that denotes availability of GCC-style built-in functions.
 */

#if defined( __GNUC__ ) || defined( __clang__ ) || \
	defined( __IBMC__ ) || defined( __IBMCPP__ ) || defined( __COMPCERT__ )

	#define KOMIHASH_GCC_BUILTINS

#endif // GCC built-ins check

/**
 * @def KOMIHASH_EC32( v )
 * @brief Macro that appies 32-bit byte-swapping, for endianness-correction.
 * @param v Value to byte-swap.
 */

/**
 * @def KOMIHASH_EC64( v )
 * @brief Macro that appies 64-bit byte-swapping, for endianness-correction.
 * @param v Value to byte-swap.
 */

#if KOMIHASH_LITTLE_ENDIAN

	#define KOMIHASH_EC32( v ) ( v )
	#define KOMIHASH_EC64( v ) ( v )

#else // KOMIHASH_LITTLE_ENDIAN

lib/Crypt/komihash.h  view on Meta::CPAN

#if defined( __clang__ )
	#define KOMIHASH_PREFETCH_1( a ) KOMIHASH_PREFETCH( a )
	#define KOMIHASH_PREFETCH_2( a )
#else // defined( __clang__ )
	#define KOMIHASH_PREFETCH_1( a )
	#define KOMIHASH_PREFETCH_2( a ) KOMIHASH_PREFETCH( a )
#endif // defined( __clang__ )

/**
 * @def KOMIHASH_INLINE
 * @brief Macro to force code inlining.
 */

#if defined( KOMIHASH_GCC_BUILTINS )

	#define KOMIHASH_INLINE inline __attribute__((always_inline))

#elif defined( _MSC_VER )

	#define KOMIHASH_INLINE inline __forceinline

lib/Crypt/komihash.h  view on Meta::CPAN

 *
 * @param u Multiplier 1.
 * @param v Multiplier 2.
 * @param[out] rl The lower half of the 128-bit result.
 * @param[in,out] rha The accumulator to receive the higher half of the
 * 128-bit result.
 */

/**
 * @def KOMIHASH_EMULU( u, v )
 * @brief Macro for 32-bit by 32-bit unsigned multiplication with 64-bit
 * result.
 * @param u Multiplier 1.
 * @param v Multiplier 2.
 */

#if defined( _MSC_VER ) && ( defined( _M_ARM64 ) || \
	( defined( _M_X64 ) && defined( __INTEL_COMPILER )))

	#include <intrin.h>

lib/Crypt/komihash.h  view on Meta::CPAN

		const uint64_t w1 = KOMIHASH_EMULU( u0, v1 ) + (uint32_t) t;

		*rha += KOMIHASH_EMULU( u1, v1 ) + (uint32_t) ( w1 >> 32 ) +
			(uint32_t) ( t >> 32 );
	}

#endif // defined( __IBMC__ )

/**
 * @def KOMIHASH_HASHROUND()
 * @brief Macro for a common hashing round without input.
 *
 * The three instructions in this macro (multiply, add, and XOR) represent the
 * simplest constantless PRNG, scalable to any even-sized state variables,
 * with the `Seed1` being the PRNG output (2^64 PRNG period). It passes
 * `PractRand` tests with rare non-systematic "unusual" evaluations.
 *
 * To make this PRNG reliable, self-starting, and eliminate a risk of
 * stopping, the following variant can be used, which adds a "register
 * checker-board", a source of raw entropy. The PRNG is available as the
 * komirand() function. Not required for hashing (but works for it) since the

lib/Crypt/komihash.h  view on Meta::CPAN

 * (the `0xAAAA...` constant should match register's size; essentially, it is
 * a replication of the `10` bit-pair; it is not an arbitrary constant).
 */

#define KOMIHASH_HASHROUND() \
	kh_m128( Seed1, Seed5, &Seed1, &Seed5 ); \
	Seed1 ^= Seed5;

/**
 * @def KOMIHASH_HASH16( m )
 * @brief Macro for a common hashing round with 16-byte input.
 * @param m Message pointer, alignment is unimportant.
 */

#define KOMIHASH_HASH16( m ) \
	kh_m128( Seed1 ^ kh_lu64ec( m ), \
		Seed5 ^ kh_lu64ec( m + 8 ), &Seed1, &Seed5 ); \
	Seed1 ^= Seed5;

/**
 * @def KOMIHASH_HASHFIN()
 * @brief Macro for common hashing finalization round.
 *
 * The final hashing input is expected in the `r1h` and `r2h` temporary
 * variables. The macro inserts the function return instruction.
 */

#define KOMIHASH_HASHFIN() \
	kh_m128( r1h, r2h, &Seed1, &Seed5 ); \
	Seed1 ^= Seed5; \
	KOMIHASH_HASHROUND(); \
	return( Seed1 );

/**
 * @def KOMIHASH_HASHLOOP64()
 * @brief Macro for a common 64-byte full-performance hashing loop.
 *
 * Expects `Msg` and `MsgLen` values (greater than 63), requires initialized
 * `Seed1-8` values.
 *
 * The "shifting" arrangement of `Seed1-4` XORs (below) does not increase
 * individual `SeedN` PRNG period beyond 2^64, but reduces a chance of any
 * occassional synchronization between PRNG lanes happening. Practically,
 * `Seed1-4` together become a single "fused" 256-bit PRNG value, having 2^66
 * summary PRNG period.
 */