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gzip: code shrink

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huft_build() still has way too many params

function                                             old     new   delta
lit                                                    -      94     +94
dist                                                   -      94     +94
huft_build                                          1058    1054      -4
inflate_block                                       1281    1254     -27
cpdext                                                30       -     -30
cplext                                                31       -     -31
cpdist                                                60       -     -60
cplens                                                62       -     -62
------------------------------------------------------------------------------
(add/remove: 2/4 grow/shrink: 0/2 up/down: 188/-214)          Total: -26 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2019-10-19 18:52:41 +02:00
parent c763392458
commit 6572ef6e1e
1 changed files with 26 additions and 29 deletions
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55
archival/libarchive/decompress_gunzip.c
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@ -184,29 +184,26 @@ static const uint16_t mask_bits[] ALIGN2 = {
0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
}; };
/* Copy lengths for literal codes 257..285 */ /* Put lengths/offsets and extra bits in a struct of arrays
static const uint16_t cplens[] ALIGN2 = { * to make calls to huft_build() have one fewer parameter.
3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31, 35, 43, 51, 59, */
67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0 struct cp_ext {
uint16_t cp[31];
uint8_t ext[31];
}; };
/* Copy lengths and extra bits for literal codes 257..285 */
/* note: see note #13 above about the 258 in this list. */ /* note: see note #13 above about the 258 in this list. */
/* Extra bits for literal codes 257..285 */ static const struct cp_ext lit = {
static const uint8_t cplext[] ALIGN1 = { /*257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 */
0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 5, /*0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 */
5, 5, 5, 0, 99, 99 { 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31, 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0 },
}; /* 99 == invalid */ { 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 99, 99 } /* 99 == invalid */
/* Copy offsets for distance codes 0..29 */
static const uint16_t cpdist[] ALIGN2 = {
1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193, 257, 385, 513,
769, 1025, 1537, 2049, 3073, 4097, 6145, 8193, 12289, 16385, 24577
}; };
/* Copy offsets and extra bits for distance codes 0..29 */
/* Extra bits for distance codes */ static const struct cp_ext dist = {
static const uint8_t cpdext[] ALIGN1 = { /*0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 */
0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10, { 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193, 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145, 8193, 12289, 16385, 24577 },
11, 11, 12, 12, 13, 13 { 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13 }
}; };
/* Tables for deflate from PKZIP's appnote.txt. */ /* Tables for deflate from PKZIP's appnote.txt. */
@ -288,8 +285,8 @@ static unsigned fill_bitbuffer(STATE_PARAM unsigned bitbuffer, unsigned *current
* result: starting table * result: starting table
*/ */
static huft_t* huft_build(const unsigned *b, const unsigned n, static huft_t* huft_build(const unsigned *b, const unsigned n,
const unsigned s, const uint16_t *d, const unsigned s, const struct cp_ext *cp_ext,
const uint8_t *e, unsigned *m) unsigned *m)
{ {
unsigned a; /* counter for codes of length k */ unsigned a; /* counter for codes of length k */
unsigned c[BMAX + 1]; /* bit length count table */ unsigned c[BMAX + 1]; /* bit length count table */
@ -447,8 +444,8 @@ static huft_t* huft_build(const unsigned *b, const unsigned n,
r.e = (unsigned char) (*p < 256 ? 16 : 15); /* 256 is EOB code */ r.e = (unsigned char) (*p < 256 ? 16 : 15); /* 256 is EOB code */
r.v.n = (unsigned short) (*p++); /* simple code is just the value */ r.v.n = (unsigned short) (*p++); /* simple code is just the value */
} else { } else {
r.e = (unsigned char) e[*p - s]; /* non-simple--look up in lists */ r.e = (unsigned char) cp_ext->ext[*p - s]; /* non-simple--look up in lists */
r.v.n = d[*p++ - s]; r.v.n = cp_ext->cp[*p++ - s];
} }
/* fill code-like entries with r */ /* fill code-like entries with r */
@ -777,14 +774,14 @@ static int inflate_block(STATE_PARAM smallint *e)
for (; i < 288; i++) /* make a complete, but wrong code set */ for (; i < 288; i++) /* make a complete, but wrong code set */
ll[i] = 8; ll[i] = 8;
bl = 7; bl = 7;
inflate_codes_tl = huft_build(ll, 288, 257, cplens, cplext, &bl); inflate_codes_tl = huft_build(ll, 288, 257, &lit, &bl);
/* huft_build() never returns error here - we use known data */ /* huft_build() never returns error here - we use known data */
/* set up distance table */ /* set up distance table */
for (i = 0; i < 30; i++) /* make an incomplete code set */ for (i = 0; i < 30; i++) /* make an incomplete code set */
ll[i] = 5; ll[i] = 5;
bd = 5; bd = 5;
inflate_codes_td = huft_build(ll, 30, 0, cpdist, cpdext, &bd); inflate_codes_td = huft_build(ll, 30, 0, &dist, &bd);
/* set up data for inflate_codes() */ /* set up data for inflate_codes() */
inflate_codes_setup(PASS_STATE bl, bd); inflate_codes_setup(PASS_STATE bl, bd);
@ -850,7 +847,7 @@ static int inflate_block(STATE_PARAM smallint *e)
/* build decoding table for trees - single level, 7 bit lookup */ /* build decoding table for trees - single level, 7 bit lookup */
bl = 7; bl = 7;
inflate_codes_tl = huft_build(ll, 19, 19, NULL, NULL, &bl); inflate_codes_tl = huft_build(ll, 19, 19, NULL, &bl);
if (!inflate_codes_tl) { if (!inflate_codes_tl) {
abort_unzip(PASS_STATE_ONLY); /* incomplete code set */ abort_unzip(PASS_STATE_ONLY); /* incomplete code set */
} }
@ -915,12 +912,12 @@ static int inflate_block(STATE_PARAM smallint *e)
/* build the decoding tables for literal/length and distance codes */ /* build the decoding tables for literal/length and distance codes */
bl = lbits; bl = lbits;
inflate_codes_tl = huft_build(ll, nl, 257, cplens, cplext, &bl); inflate_codes_tl = huft_build(ll, nl, 257, &lit, &bl);
if (!inflate_codes_tl) { if (!inflate_codes_tl) {
abort_unzip(PASS_STATE_ONLY); abort_unzip(PASS_STATE_ONLY);
} }
bd = dbits; bd = dbits;
inflate_codes_td = huft_build(ll + nl, nd, 0, cpdist, cpdext, &bd); inflate_codes_td = huft_build(ll + nl, nd, 0, &dist, &bd);
if (!inflate_codes_td) { if (!inflate_codes_td) {
abort_unzip(PASS_STATE_ONLY); abort_unzip(PASS_STATE_ONLY);
} }