Digest-FNV-XS/XS.xs

#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"

#define INIT32 2166136261U
#define MULT32 16777619U
#define INIT64 14695981039346656037U
#define MULT64 1099511628211U

static UV
fnv1_32 (SV *data, U32 h)
{
  STRLEN l;
  U8 *p = (U8 *)SvPVbyte (data, l);

  while (l--)
    {
      h *= MULT32;
      h ^= *p++;
    }

  return h;
}

static UV
fnv1a_32 (SV *data, U32 h)
{
  STRLEN l;
  U8 *p = (U8 *)SvPVbyte (data, l);

  while (l--)
    {
      h ^= *p++;
      h *= MULT32;
    }

  return h;
}

#if UVSIZE >= 8

static UV
fnv1_64 (SV *data, UV h)
{
  STRLEN l;
  U8 *p = (U8 *)SvPVbyte (data, l);

  while (l--)
    {
      h *= MULT64;
      h ^= *p++;
    }

  return h;
}

static UV
fnv1a_64 (SV *data, UV h)
{
  STRLEN l;
  U8 *p = (U8 *)SvPVbyte (data, l);

  while (l--)
    {
      h ^= *p++;
      h *= MULT64;
    }

  return h;
}

#endif

#define fnv0_32 fnv1_32
#define fnv0_64 fnv1_64

static UV
xorfold (UV hash, int bits, int max)
{
  if (bits < max)
    hash = ((hash >> (max - bits)) ^ hash) & ((1 << bits) - 1);

  return hash;
}

#define xorfold_32(hash,bits) xorfold (hash, bits, 32)
#define xorfold_64(hash,bits) xorfold (hash, bits, 64)

static UV
reduce_32 (U32 hash, U32 range)
{
  U32 retry =         0xffffffffU / range * range;

  while (hash >= retry)
    hash = hash * MULT32 + INIT32;

  return hash % range;
}

static UV
reduce_64 (UV hash, UV range)
{
  U32 retry = 0xffffffffffffffffU / range * range;

  while (hash >= retry)
    hash = hash * MULT64 + INIT64;

  return hash % range;
}

MODULE = Digest::FNV::XS                PACKAGE = Digest::FNV::XS

PROTOTYPES: ENABLE

UV fnv0_32  (SV *data, SV *init = &PL_sv_undef)
        C_ARGS: data, SvUV (init)

UV fnv1_32  (SV *data, SV *init = &PL_sv_undef)
        C_ARGS: data, SvOK (init) ? SvUV (init) : INIT32

UV fnv1a_32 (SV *data, SV *init = &PL_sv_undef)
        C_ARGS: data, SvOK (init) ? SvUV (init) : INIT32

#if UVSIZE >= 8

UV fnv0_64  (SV *data, SV *init = &PL_sv_undef)
        C_ARGS: data, SvUV (init)

UV fnv1_64  (SV *data, SV *init = &PL_sv_undef)
        C_ARGS: data, SvOK (init) ? SvUV (init) : INIT64

UV fnv1a_64 (SV *data, SV *init = &PL_sv_undef)
        C_ARGS: data, SvOK (init) ? SvUV (init) : INIT64

#endif

UV xorfold_32 (UV hash, int bits)

UV xorfold_64 (UV hash, int bits)

UV reduce_32 (UV hash, UV range)

UV reduce_64 (UV hash, UV range)

Revision:	1.1
Committed:	Thu Oct 29 10:56:00 2015 UTC (8 years, 6 months ago) by root
Branch:	MAIN
CVS Tags:	rel-0_02, HEAD
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.1	#include "EXTERN.h"
2			#include "perl.h"
3			#include "XSUB.h"
4
5			#define INIT32 2166136261U
6			#define MULT32 16777619U
7			#define INIT64 14695981039346656037U
8			#define MULT64 1099511628211U
9
10			static UV
11			fnv1_32 (SV *data, U32 h)
12			{
13			STRLEN l;
14			U8 p = (U8 )SvPVbyte (data, l);
15
16			while (l--)
17			{
18			h *= MULT32;
19			h ^= *p++;
20			}
21
22			return h;
23			}
24
25			static UV
26			fnv1a_32 (SV *data, U32 h)
27			{
28			STRLEN l;
29			U8 p = (U8 )SvPVbyte (data, l);
30
31			while (l--)
32			{
33			h ^= *p++;
34			h *= MULT32;
35			}
36
37			return h;
38			}
39
40			#if UVSIZE >= 8
41
42			static UV
43			fnv1_64 (SV *data, UV h)
44			{
45			STRLEN l;
46			U8 p = (U8 )SvPVbyte (data, l);
47
48			while (l--)
49			{
50			h *= MULT64;
51			h ^= *p++;
52			}
53
54			return h;
55			}
56
57			static UV
58			fnv1a_64 (SV *data, UV h)
59			{
60			STRLEN l;
61			U8 p = (U8 )SvPVbyte (data, l);
62
63			while (l--)
64			{
65			h ^= *p++;
66			h *= MULT64;
67			}
68
69			return h;
70			}
71
72			#endif
73
74			#define fnv0_32 fnv1_32
75			#define fnv0_64 fnv1_64
76
77			static UV
78			xorfold (UV hash, int bits, int max)
79			{
80			if (bits < max)
81			hash = ((hash >> (max - bits)) ^ hash) & ((1 << bits) - 1);
82
83			return hash;
84			}
85
86			#define xorfold_32(hash,bits) xorfold (hash, bits, 32)
87			#define xorfold_64(hash,bits) xorfold (hash, bits, 64)
88
89			static UV
90			reduce_32 (U32 hash, U32 range)
91			{
92			U32 retry = 0xffffffffU / range * range;
93
94			while (hash >= retry)
95			hash = hash * MULT32 + INIT32;
96
97			return hash % range;
98			}
99
100			static UV
101			reduce_64 (UV hash, UV range)
102			{
103			U32 retry = 0xffffffffffffffffU / range * range;
104
105			while (hash >= retry)
106			hash = hash * MULT64 + INIT64;
107
108			return hash % range;
109			}
110
111			MODULE = Digest::FNV::XS PACKAGE = Digest::FNV::XS
112
113			PROTOTYPES: ENABLE
114
115			UV fnv0_32 (SV data, SV init = &PL_sv_undef)
116			C_ARGS: data, SvUV (init)
117
118			UV fnv1_32 (SV data, SV init = &PL_sv_undef)
119			C_ARGS: data, SvOK (init) ? SvUV (init) : INIT32
120
121			UV fnv1a_32 (SV data, SV init = &PL_sv_undef)
122			C_ARGS: data, SvOK (init) ? SvUV (init) : INIT32
123
124			#if UVSIZE >= 8
125
126			UV fnv0_64 (SV data, SV init = &PL_sv_undef)
127			C_ARGS: data, SvUV (init)
128
129			UV fnv1_64 (SV data, SV init = &PL_sv_undef)
130			C_ARGS: data, SvOK (init) ? SvUV (init) : INIT64
131
132			UV fnv1a_64 (SV data, SV init = &PL_sv_undef)
133			C_ARGS: data, SvOK (init) ? SvUV (init) : INIT64
134
135			#endif
136
137			UV xorfold_32 (UV hash, int bits)
138
139			UV xorfold_64 (UV hash, int bits)
140
141			UV reduce_32 (UV hash, UV range)
142
143			UV reduce_64 (UV hash, UV range)
144