xref: /openbmc/linux/lib/lz4/lz4defs.h (revision bc5aa3a0)
1 /*
2  * lz4defs.h -- architecture specific defines
3  *
4  * Copyright (C) 2013, LG Electronics, Kyungsik Lee <kyungsik.lee@lge.com>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  */
10 
11 /*
12  * Detects 64 bits mode
13  */
14 #if defined(CONFIG_64BIT)
15 #define LZ4_ARCH64 1
16 #else
17 #define LZ4_ARCH64 0
18 #endif
19 
20 /*
21  * Architecture-specific macros
22  */
23 #define BYTE	u8
24 typedef struct _U16_S { u16 v; } U16_S;
25 typedef struct _U32_S { u32 v; } U32_S;
26 typedef struct _U64_S { u64 v; } U64_S;
27 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
28 
29 #define A16(x) (((U16_S *)(x))->v)
30 #define A32(x) (((U32_S *)(x))->v)
31 #define A64(x) (((U64_S *)(x))->v)
32 
33 #define PUT4(s, d) (A32(d) = A32(s))
34 #define PUT8(s, d) (A64(d) = A64(s))
35 
36 #define LZ4_READ_LITTLEENDIAN_16(d, s, p)	\
37 	(d = s - A16(p))
38 
39 #define LZ4_WRITE_LITTLEENDIAN_16(p, v)	\
40 	do {	\
41 		A16(p) = v; \
42 		p += 2; \
43 	} while (0)
44 #else /* CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS */
45 
46 #define A64(x) get_unaligned((u64 *)&(((U16_S *)(x))->v))
47 #define A32(x) get_unaligned((u32 *)&(((U16_S *)(x))->v))
48 #define A16(x) get_unaligned((u16 *)&(((U16_S *)(x))->v))
49 
50 #define PUT4(s, d) \
51 	put_unaligned(get_unaligned((const u32 *) s), (u32 *) d)
52 #define PUT8(s, d) \
53 	put_unaligned(get_unaligned((const u64 *) s), (u64 *) d)
54 
55 #define LZ4_READ_LITTLEENDIAN_16(d, s, p)	\
56 	(d = s - get_unaligned_le16(p))
57 
58 #define LZ4_WRITE_LITTLEENDIAN_16(p, v)			\
59 	do {						\
60 		put_unaligned_le16(v, (u16 *)(p));	\
61 		p += 2;					\
62 	} while (0)
63 #endif
64 
65 #define COPYLENGTH 8
66 #define ML_BITS  4
67 #define ML_MASK  ((1U << ML_BITS) - 1)
68 #define RUN_BITS (8 - ML_BITS)
69 #define RUN_MASK ((1U << RUN_BITS) - 1)
70 #define MEMORY_USAGE	14
71 #define MINMATCH	4
72 #define SKIPSTRENGTH	6
73 #define LASTLITERALS	5
74 #define MFLIMIT		(COPYLENGTH + MINMATCH)
75 #define MINLENGTH	(MFLIMIT + 1)
76 #define MAXD_LOG	16
77 #define MAXD		(1 << MAXD_LOG)
78 #define MAXD_MASK	(u32)(MAXD - 1)
79 #define MAX_DISTANCE	(MAXD - 1)
80 #define HASH_LOG	(MAXD_LOG - 1)
81 #define HASHTABLESIZE	(1 << HASH_LOG)
82 #define MAX_NB_ATTEMPTS	256
83 #define OPTIMAL_ML	(int)((ML_MASK-1)+MINMATCH)
84 #define LZ4_64KLIMIT	((1<<16) + (MFLIMIT - 1))
85 #define HASHLOG64K	((MEMORY_USAGE - 2) + 1)
86 #define HASH64KTABLESIZE	(1U << HASHLOG64K)
87 #define LZ4_HASH_VALUE(p)	(((A32(p)) * 2654435761U) >> \
88 				((MINMATCH * 8) - (MEMORY_USAGE-2)))
89 #define LZ4_HASH64K_VALUE(p)	(((A32(p)) * 2654435761U) >> \
90 				((MINMATCH * 8) - HASHLOG64K))
91 #define HASH_VALUE(p)		(((A32(p)) * 2654435761U) >> \
92 				((MINMATCH * 8) - HASH_LOG))
93 
94 #if LZ4_ARCH64/* 64-bit */
95 #define STEPSIZE 8
96 
97 #define LZ4_COPYSTEP(s, d)	\
98 	do {			\
99 		PUT8(s, d);	\
100 		d += 8;		\
101 		s += 8;		\
102 	} while (0)
103 
104 #define LZ4_COPYPACKET(s, d)	LZ4_COPYSTEP(s, d)
105 
106 #define LZ4_SECURECOPY(s, d, e)			\
107 	do {					\
108 		if (d < e) {			\
109 			LZ4_WILDCOPY(s, d, e);	\
110 		}				\
111 	} while (0)
112 #define HTYPE u32
113 
114 #ifdef __BIG_ENDIAN
115 #define LZ4_NBCOMMONBYTES(val) (__builtin_clzll(val) >> 3)
116 #else
117 #define LZ4_NBCOMMONBYTES(val) (__builtin_ctzll(val) >> 3)
118 #endif
119 
120 #else	/* 32-bit */
121 #define STEPSIZE 4
122 
123 #define LZ4_COPYSTEP(s, d)	\
124 	do {			\
125 		PUT4(s, d);	\
126 		d += 4;		\
127 		s += 4;		\
128 	} while (0)
129 
130 #define LZ4_COPYPACKET(s, d)		\
131 	do {				\
132 		LZ4_COPYSTEP(s, d);	\
133 		LZ4_COPYSTEP(s, d);	\
134 	} while (0)
135 
136 #define LZ4_SECURECOPY	LZ4_WILDCOPY
137 #define HTYPE const u8*
138 
139 #ifdef __BIG_ENDIAN
140 #define LZ4_NBCOMMONBYTES(val) (__builtin_clz(val) >> 3)
141 #else
142 #define LZ4_NBCOMMONBYTES(val) (__builtin_ctz(val) >> 3)
143 #endif
144 
145 #endif
146 
147 #define LZ4_WILDCOPY(s, d, e)		\
148 	do {				\
149 		LZ4_COPYPACKET(s, d);	\
150 	} while (d < e)
151 
152 #define LZ4_BLINDCOPY(s, d, l)	\
153 	do {	\
154 		u8 *e = (d) + l;	\
155 		LZ4_WILDCOPY(s, d, e);	\
156 		d = e;	\
157 	} while (0)
158