[mirror_edk2.git] / BaseTools / Source / C / BrotliCompress / enc / context.h

/* Copyright 2013 Google Inc. All Rights Reserved.\r
\r
   Distributed under MIT license.\r
   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT\r
*/\r
\r
/* Functions to map previous bytes into a context id. */\r
\r
#ifndef BROTLI_ENC_CONTEXT_H_\r
#define BROTLI_ENC_CONTEXT_H_\r
\r
#include "../common/types.h"\r
#include "../common/port.h"\r
\r
#if defined(__cplusplus) || defined(c_plusplus)\r
extern "C" {\r
#endif\r
\r
/* Second-order context lookup table for UTF8 byte streams.\r
\r
   If p1 and p2 are the previous two bytes, we calculate the context as\r
\r
     context = kUTF8ContextLookup[p1] | kUTF8ContextLookup[p2 + 256].\r
\r
   If the previous two bytes are ASCII characters (i.e. < 128), this will be\r
   equivalent to\r
\r
     context = 4 * context1(p1) + context2(p2),\r
\r
   where context1 is based on the previous byte in the following way:\r
\r
     0  : non-ASCII control\r
     1  : \t, \n, \r\r
     2  : space\r
     3  : other punctuation\r
     4  : " '\r
     5  : %\r
     6  : ( < [ {\r
     7  : ) > ] }\r
     8  : , ; :\r
     9  : .\r
     10 : =\r
     11 : number\r
     12 : upper-case vowel\r
     13 : upper-case consonant\r
     14 : lower-case vowel\r
     15 : lower-case consonant\r
\r
   and context2 is based on the second last byte:\r
\r
     0 : control, space\r
     1 : punctuation\r
     2 : upper-case letter, number\r
     3 : lower-case letter\r
\r
   If the last byte is ASCII, and the second last byte is not (in a valid UTF8\r
   stream it will be a continuation byte, value between 128 and 191), the\r
   context is the same as if the second last byte was an ASCII control or space.\r
\r
   If the last byte is a UTF8 lead byte (value >= 192), then the next byte will\r
   be a continuation byte and the context id is 2 or 3 depending on the LSB of\r
   the last byte and to a lesser extent on the second last byte if it is ASCII.\r
\r
   If the last byte is a UTF8 continuation byte, the second last byte can be:\r
     - continuation byte: the next byte is probably ASCII or lead byte (assuming\r
       4-byte UTF8 characters are rare) and the context id is 0 or 1.\r
     - lead byte (192 - 207): next byte is ASCII or lead byte, context is 0 or 1\r
     - lead byte (208 - 255): next byte is continuation byte, context is 2 or 3\r
\r
   The possible value combinations of the previous two bytes, the range of\r
   context ids and the type of the next byte is summarized in the table below:\r
\r
   |--------\-----------------------------------------------------------------|\r
   |         \                         Last byte                              |\r
   | Second   \---------------------------------------------------------------|\r
   | last byte \    ASCII            |   cont. byte        |   lead byte      |\r
   |            \   (0-127)          |   (128-191)         |   (192-)         |\r
   |=============|===================|=====================|==================|\r
   |  ASCII      | next: ASCII/lead  |  not valid          |  next: cont.     |\r
   |  (0-127)    | context: 4 - 63   |                     |  context: 2 - 3  |\r
   |-------------|-------------------|---------------------|------------------|\r
   |  cont. byte | next: ASCII/lead  |  next: ASCII/lead   |  next: cont.     |\r
   |  (128-191)  | context: 4 - 63   |  context: 0 - 1     |  context: 2 - 3  |\r
   |-------------|-------------------|---------------------|------------------|\r
   |  lead byte  | not valid         |  next: ASCII/lead   |  not valid       |\r
   |  (192-207)  |                   |  context: 0 - 1     |                  |\r
   |-------------|-------------------|---------------------|------------------|\r
   |  lead byte  | not valid         |  next: cont.        |  not valid       |\r
   |  (208-)     |                   |  context: 2 - 3     |                  |\r
   |-------------|-------------------|---------------------|------------------|\r
*/\r
static const uint8_t kUTF8ContextLookup[512] = {\r
  /* Last byte. */\r
  /* */\r
  /* ASCII range. */\r
   0,  0,  0,  0,  0,  0,  0,  0,  0,  4,  4,  0,  0,  4,  0,  0,\r
   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,\r
   8, 12, 16, 12, 12, 20, 12, 16, 24, 28, 12, 12, 32, 12, 36, 12,\r
  44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 32, 32, 24, 40, 28, 12,\r
  12, 48, 52, 52, 52, 48, 52, 52, 52, 48, 52, 52, 52, 52, 52, 48,\r
  52, 52, 52, 52, 52, 48, 52, 52, 52, 52, 52, 24, 12, 28, 12, 12,\r
  12, 56, 60, 60, 60, 56, 60, 60, 60, 56, 60, 60, 60, 60, 60, 56,\r
  60, 60, 60, 60, 60, 56, 60, 60, 60, 60, 60, 24, 12, 28, 12,  0,\r
  /* UTF8 continuation byte range. */\r
  0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,\r
  0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,\r
  0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,\r
  0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,\r
  /* UTF8 lead byte range. */\r
  2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3,\r
  2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3,\r
  2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3,\r
  2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3,\r
  /* Second last byte. */\r
  /* */\r
  /* ASCII range. */\r
  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,\r
  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,\r
  0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,\r
  2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1,\r
  1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,\r
  2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1,\r
  1, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,\r
  3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 1, 1, 1, 1, 0,\r
  /* UTF8 continuation byte range. */\r
  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,\r
  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,\r
  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,\r
  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,\r
  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,\r
  /* UTF8 lead byte range. */\r
  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,\r
  2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,\r
  2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,\r
};\r
\r
/* Context lookup table for small signed integers. */\r
static const uint8_t kSigned3BitContextLookup[] = {\r
  0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,\r
  2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,\r
  2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,\r
  2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,\r
  3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,\r
  3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,\r
  3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,\r
  3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,\r
  4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,\r
  4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,\r
  4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,\r
  4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,\r
  5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,\r
  5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,\r
  5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,\r
  6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 7,\r
};\r
\r
typedef enum ContextType {\r
  CONTEXT_LSB6         = 0,\r
  CONTEXT_MSB6         = 1,\r
  CONTEXT_UTF8         = 2,\r
  CONTEXT_SIGNED       = 3\r
} ContextType;\r
\r
static BROTLI_INLINE uint8_t Context(uint8_t p1, uint8_t p2, ContextType mode) {\r
  switch (mode) {\r
    case CONTEXT_LSB6:\r
      return p1 & 0x3f;\r
    case CONTEXT_MSB6:\r
      return (uint8_t)(p1 >> 2);\r
    case CONTEXT_UTF8:\r
      return kUTF8ContextLookup[p1] | kUTF8ContextLookup[p2 + 256];\r
    case CONTEXT_SIGNED:\r
      return (uint8_t)((kSigned3BitContextLookup[p1] << 3) +\r
                       kSigned3BitContextLookup[p2]);\r
    default:\r
      return 0;\r
  }\r
}\r
\r
#if defined(__cplusplus) || defined(c_plusplus)\r
}  /* extern "C" */\r
#endif\r
\r
#endif  /* BROTLI_ENC_CONTEXT_H_ */\r
Commit	Line	Data
11b7501a SB	1	/* Copyright 2013 Google Inc. All Rights Reserved.\r
	2	\r
	3	Distributed under MIT license.\r
	4	See file LICENSE for detail or copy at https://opensource.org/licenses/MIT\r
	5	*/\r
	6	\r
	7	/* Functions to map previous bytes into a context id. */\r
	8	\r
	9	#ifndef BROTLI_ENC_CONTEXT_H_\r
	10	#define BROTLI_ENC_CONTEXT_H_\r
	11	\r
	12	#include "../common/types.h"\r
	13	#include "../common/port.h"\r
	14	\r
	15	#if defined(__cplusplus) \|\| defined(c_plusplus)\r
	16	extern "C" {\r
	17	#endif\r
	18	\r
	19	/* Second-order context lookup table for UTF8 byte streams.\r
	20	\r
	21	If p1 and p2 are the previous two bytes, we calculate the context as\r
	22	\r
	23	context = kUTF8ContextLookup[p1] \| kUTF8ContextLookup[p2 + 256].\r
	24	\r
	25	If the previous two bytes are ASCII characters (i.e. < 128), this will be\r
	26	equivalent to\r
	27	\r
	28	context = 4 * context1(p1) + context2(p2),\r
	29	\r
	30	where context1 is based on the previous byte in the following way:\r
	31	\r
	32	0 : non-ASCII control\r
	33	1 : \t, \n, \r\r
	34	2 : space\r
	35	3 : other punctuation\r
	36	4 : " '\r
	37	5 : %\r
	38	6 : ( < [ {\r
	39	7 : ) > ] }\r
	40	8 : , ; :\r
	41	9 : .\r
	42	10 : =\r
	43	11 : number\r
	44	12 : upper-case vowel\r
	45	13 : upper-case consonant\r
	46	14 : lower-case vowel\r
	47	15 : lower-case consonant\r
	48	\r
	49	and context2 is based on the second last byte:\r
	50	\r
	51	0 : control, space\r
	52	1 : punctuation\r
	53	2 : upper-case letter, number\r
	54	3 : lower-case letter\r
	55	\r
	56	If the last byte is ASCII, and the second last byte is not (in a valid UTF8\r
	57	stream it will be a continuation byte, value between 128 and 191), the\r
	58	context is the same as if the second last byte was an ASCII control or space.\r
	59	\r
	60	If the last byte is a UTF8 lead byte (value >= 192), then the next byte will\r
	61	be a continuation byte and the context id is 2 or 3 depending on the LSB of\r
	62	the last byte and to a lesser extent on the second last byte if it is ASCII.\r
	63	\r
	64	If the last byte is a UTF8 continuation byte, the second last byte can be:\r
65	- continuation byte: the next byte is probably ASCII or lead byte (assuming\r
66	4-byte UTF8 characters are rare) and the context id is 0 or 1.\r
67	- lead byte (192 - 207): next byte is ASCII or lead byte, context is 0 or 1\r
68	- lead byte (208 - 255): next byte is continuation byte, context is 2 or 3\r
69	\r
70	The possible value combinations of the previous two bytes, the range of\r
71	context ids and the type of the next byte is summarized in the table below:\r
72	\r
73	\|--------\-----------------------------------------------------------------\|\r
74	\| \ Last byte \|\r
75	\| Second \---------------------------------------------------------------\|\r
76	\| last byte \ ASCII \| cont. byte \| lead byte \|\r
77	\| \ (0-127) \| (128-191) \| (192-) \|\r
78	\|=============\|===================\|=====================\|==================\|\r
79	\| ASCII \| next: ASCII/lead \| not valid \| next: cont. \|\r
80	\| (0-127) \| context: 4 - 63 \| \| context: 2 - 3 \|\r
81	\|-------------\|-------------------\|---------------------\|------------------\|\r
82	\| cont. byte \| next: ASCII/lead \| next: ASCII/lead \| next: cont. \|\r
83	\| (128-191) \| context: 4 - 63 \| context: 0 - 1 \| context: 2 - 3 \|\r
84	\|-------------\|-------------------\|---------------------\|------------------\|\r
85	\| lead byte \| not valid \| next: ASCII/lead \| not valid \|\r
86	\| (192-207) \| \| context: 0 - 1 \| \|\r
87	\|-------------\|-------------------\|---------------------\|------------------\|\r
88	\| lead byte \| not valid \| next: cont. \| not valid \|\r
89	\| (208-) \| \| context: 2 - 3 \| \|\r
90	\|-------------\|-------------------\|---------------------\|------------------\|\r
91	*/\r
92	static const uint8_t kUTF8ContextLookup[512] = {\r
93	/* Last byte. */\r
94	/* */\r
95	/* ASCII range. */\r
96	0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 4, 0, 0, 4, 0, 0,\r
97	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,\r
98	8, 12, 16, 12, 12, 20, 12, 16, 24, 28, 12, 12, 32, 12, 36, 12,\r
99	44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 32, 32, 24, 40, 28, 12,\r
100	12, 48, 52, 52, 52, 48, 52, 52, 52, 48, 52, 52, 52, 52, 52, 48,\r
101	52, 52, 52, 52, 52, 48, 52, 52, 52, 52, 52, 24, 12, 28, 12, 12,\r
102	12, 56, 60, 60, 60, 56, 60, 60, 60, 56, 60, 60, 60, 60, 60, 56,\r
103	60, 60, 60, 60, 60, 56, 60, 60, 60, 60, 60, 24, 12, 28, 12, 0,\r
104	/* UTF8 continuation byte range. */\r
105	0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,\r
106	0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,\r
107	0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,\r
108	0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,\r
109	/* UTF8 lead byte range. */\r
110	2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3,\r
111	2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3,\r
112	2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3,\r
113	2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3,\r
114	/* Second last byte. */\r
115	/* */\r
116	/* ASCII range. */\r
117	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,\r
118	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,\r
119	0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,\r
120	2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1,\r
121	1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,\r
122	2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1,\r
123	1, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,\r
124	3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 1, 1, 1, 1, 0,\r
125	/* UTF8 continuation byte range. */\r
126	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,\r
127	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,\r
128	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,\r
129	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,\r
130	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,\r
131	/* UTF8 lead byte range. */\r
132	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,\r
133	2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,\r
134	2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,\r
135	};\r
136	\r
137	/* Context lookup table for small signed integers. */\r
138	static const uint8_t kSigned3BitContextLookup[] = {\r
139	0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,\r
140	2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,\r
141	2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,\r
142	2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,\r
143	3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,\r
144	3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,\r
145	3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,\r
146	3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,\r
147	4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,\r
148	4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,\r
149	4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,\r
150	4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,\r
151	5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,\r
152	5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,\r
153	5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,\r
154	6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 7,\r
155	};\r
156	\r
157	typedef enum ContextType {\r
158	CONTEXT_LSB6 = 0,\r
159	CONTEXT_MSB6 = 1,\r
160	CONTEXT_UTF8 = 2,\r
161	CONTEXT_SIGNED = 3\r
162	} ContextType;\r
163	\r
164	static BROTLI_INLINE uint8_t Context(uint8_t p1, uint8_t p2, ContextType mode) {\r
165	switch (mode) {\r
166	case CONTEXT_LSB6:\r
167	return p1 & 0x3f;\r
168	case CONTEXT_MSB6:\r
169	return (uint8_t)(p1 >> 2);\r
170	case CONTEXT_UTF8:\r
171	return kUTF8ContextLookup[p1] \| kUTF8ContextLookup[p2 + 256];\r
172	case CONTEXT_SIGNED:\r
173	return (uint8_t)((kSigned3BitContextLookup[p1] << 3) +\r
174	kSigned3BitContextLookup[p2]);\r
175	default:\r
176	return 0;\r
177	}\r
178	}\r
179	\r
180	#if defined(__cplusplus) \|\| defined(c_plusplus)\r
181	} /* extern "C" */\r
182	#endif\r
183	\r
184	#endif /* BROTLI_ENC_CONTEXT_H_ */\r