66 lines
2.2 KiB
Groff
66 lines
2.2 KiB
Groff
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.\" $NetBSD: mi_vector_hash.3,v 1.2 2009/07/21 12:40:52 joerg Exp $
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.\"
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.\" Copyright (c) 2009 The NetBSD Foundation, Inc.
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.\" All rights reserved.
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.\"
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.\" This code is derived from software contributed to The NetBSD Foundation
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.\" by Joerg Sonnenberger.
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.\"
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.\" Redistribution and use in source and binary forms, with or without
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.\" modification, are permitted provided that the following conditions
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.\" are met:
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.\" 1. Redistributions of source code must retain the above copyright
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.\" notice, this list of conditions and the following disclaimer.
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.\" 2. Redistributions in binary form must reproduce the above copyright
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.\" notice, this list of conditions and the following disclaimer in the
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.\" documentation and/or other materials provided with the distribution.
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.\"
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.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
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.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
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.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
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.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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.\" POSSIBILITY OF SUCH DAMAGE.
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.\"
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.Dd July 13, 2009
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.Dt MI_VECTOR_HASH 3
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.Os
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.Sh NAME
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.Nm mi_vector_hash
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.Nd fast 32bit hash functions
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.Sh LIBRARY
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.Lb libc
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.Sh SYNOPSIS
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.In stdlib.h
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.Ft void
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.Fn mi_vector_hash "const void * restrict key" "size_t len" \
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"uint32_t seed" "uint32_t hashes[3]"
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.Sh DESCRIPTION
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The
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.Nm
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function computes three 32-bit hash values of the memory area starting at
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.Fa key
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with length
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.Fa len .
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.Pp
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The output is identical on all architectures and only depends on
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.Fa key
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and
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.Fa seed .
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.Sh IMPLEMENTATION NOTES
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An optimised code path is used if
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.Fa key
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is aligned on a 32-bit boundary.
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.Sh HISTORY
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The
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.Nm
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function appeared in
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.Nx 6.0 .
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.Sh AUTHORS
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The hash function has been created by Bob Jenkins.
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