xref: /netbsd-src/lib/libc/stdlib/mi_vector_hash.3 (revision ed9dacacc0b0e89c95dd4a827d0c7d8edbc4c7ff)
1.\"	$NetBSD: mi_vector_hash.3,v 1.2 2009/07/21 12:40:52 joerg Exp $
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30.Dd July 13, 2009
31.Dt MI_VECTOR_HASH 3
32.Os
33.Sh NAME
34.Nm mi_vector_hash
35.Nd fast 32bit hash functions
36.Sh LIBRARY
37.Lb libc
38.Sh SYNOPSIS
39.In stdlib.h
40.Ft void
41.Fn mi_vector_hash "const void * restrict key" "size_t len" \
42    "uint32_t seed" "uint32_t hashes[3]"
43.Sh DESCRIPTION
44The
45.Nm
46function computes three 32-bit hash values of the memory area starting at
47.Fa key
48with length
49.Fa len .
50.Pp
51The output is identical on all architectures and only depends on
52.Fa key
53and
54.Fa seed .
55.Sh IMPLEMENTATION NOTES
56An optimised code path is used if
57.Fa key
58is aligned on a 32-bit boundary.
59.Sh HISTORY
60The
61.Nm
62function appeared in
63.Nx 6.0 .
64.Sh AUTHORS
65The hash function has been created by Bob Jenkins.
66