minix/lib/libc/stdlib/mi_vector_hash.3

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.\" $NetBSD: mi_vector_hash.3,v 1.2 2009/07/21 12:40:52 joerg Exp $
.\"
.\" Copyright (c) 2009 The NetBSD Foundation, Inc.
.\" All rights reserved.
.\"
.\" This code is derived from software contributed to The NetBSD Foundation
.\" by Joerg Sonnenberger.
.\"
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.\" modification, are permitted provided that the following conditions
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.Dd July 13, 2009
.Dt MI_VECTOR_HASH 3
.Os
.Sh NAME
.Nm mi_vector_hash
.Nd fast 32bit hash functions
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In stdlib.h
.Ft void
.Fn mi_vector_hash "const void * restrict key" "size_t len" \
"uint32_t seed" "uint32_t hashes[3]"
.Sh DESCRIPTION
The
.Nm
function computes three 32-bit hash values of the memory area starting at
.Fa key
with length
.Fa len .
.Pp
The output is identical on all architectures and only depends on
.Fa key
and
.Fa seed .
.Sh IMPLEMENTATION NOTES
An optimised code path is used if
.Fa key
is aligned on a 32-bit boundary.
.Sh HISTORY
The
.Nm
function appeared in
.Nx 6.0 .
.Sh AUTHORS
The hash function has been created by Bob Jenkins.