diff options
| -rw-r--r-- | Changes | 5 | ||||
| -rw-r--r-- | Makefile.in | 2 | ||||
| -rw-r--r-- | bench.c | 2 | ||||
| -rw-r--r-- | lzf.h | 13 | ||||
| -rw-r--r-- | lzfP.h | 37 | ||||
| -rw-r--r-- | lzf_c.c | 22 |
6 files changed, 58 insertions, 23 deletions
@@ -1,3 +1,8 @@ +1.5 Tue Mar 8 20:23:23 CET 2005 + - incorporated improvements by Adam D. Moss, + which includes a new VERY_FAST mode which is + a bit slower than ULTRA_FAST but much better, + and enabled it as default. 1.401 Thu Mar 3 18:00:52 CET 2005 - use cstring in c++, not string.h. diff --git a/Makefile.in b/Makefile.in index f94e0cc..cec120a 100644 --- a/Makefile.in +++ b/Makefile.in @@ -1,4 +1,4 @@ -VERSION = 1.401 +VERSION = 1.5 prefix = @prefix@ exec_prefix = @exec_prefix@ @@ -40,7 +40,7 @@ int main(void) fread (data, DSIZE, 1, f); fclose (f); - for (lp = 0; lp < 100; lp++) { + for (lp = 0; lp < 1000; lp++) { s=stamp(); l = lzf_compress (data, DSIZE, data2, DSIZE*2); j = lzf_decompress (data2, l, data3, DSIZE*2); @@ -48,6 +48,8 @@ ** ***********************************************************************/ +#define LZF_VERSION 0x0105 /* 1.5 */ + /* * Compress in_len bytes stored at the memory block starting at * in_data and write the result to out_data, up to a maximum length @@ -60,15 +62,16 @@ * the data uncompressed otherwise. * * lzf_compress might use different algorithms on different systems and - * thus might result in different compressed strings depending on the - * phase of the moon or similar factors. However, all these strings are - * architecture-independent and will result in the original data when - * decompressed using lzf_decompress. + * even diferent runs, thus might result in different compressed strings + * depending on the phase of the moon or similar factors. However, all + * these strings are architecture-independent and will result in the + * original data when decompressed using lzf_decompress. * * The buffers must not be overlapping. * * If the option LZF_STATE_ARG is enabled, an extra argument must be - * supplied which is not reflected in this header file. Refer to lzf_c.c. + * supplied which is not reflected in this header file. Refer to lzfP.h + * and lzf_c.c. * */ unsigned int @@ -39,7 +39,7 @@ #ifndef LZFP_h #define LZFP_h -#define STANDALONE /* at the moment, this is ok. */ +#define STANDALONE 1 /* at the moment, this is ok. */ #ifndef STANDALONE # include "lzf.h" @@ -49,29 +49,40 @@ * size of hashtable is (1 << HLOG) * sizeof (char *) * decompression is independent of the hash table size * the difference between 15 and 14 is very small - * for small blocks (and 14 is also faster). - * For a low-memory configuration, use HLOG == 13; - * For best compression, use 15 or 16. + * for small blocks (and 14 is usually a but faster). + * For a low-memory/faster configuration, use HLOG == 13; + * For best compression, use 15 or 16 (or more). */ #ifndef HLOG # define HLOG 14 #endif /* - * sacrifice some compression quality in favour of compression speed. + * sacrifice very little compression quality in favour of compression speed. + * This gives almost the same compression as the default code, and is + * (very roughly) 15% faster. This is the preferable mode of operation. + */ + +#ifndef VERY_FAST +# define VERY_FAST 1 +#endif + +/* + * sacrifice some more compression quality in favour of compression speed. * (roughly 1-2% worse compression for large blocks and * 9-10% for small, redundant, blocks and >>20% better speed in both cases) - * In short: enable this for binary data, disable this for text data. + * In short: when in need for speed, enable this for binary data, + * possibly disable this for text data. */ #ifndef ULTRA_FAST -# define ULTRA_FAST 1 +# define ULTRA_FAST 0 #endif /* * unconditionally aligning does not cost very much, so do it if unsure */ #ifndef STRICT_ALIGN -# define STRICT_ALIGN !defined(__i386) +# define STRICT_ALIGN !(defined(__i386) || defined (__amd64)) #endif /* @@ -83,8 +94,8 @@ #endif /* - * you may choose to pre-set the hash table (might be faster on modern cpus - * and large (>>64k) blocks) + * you may choose to pre-set the hash table (might be faster on some + * modern cpus and large (>>64k) blocks) */ #ifndef INIT_HTAB # define INIT_HTAB 0 @@ -128,6 +139,12 @@ typedef const u8 *LZF_STATE[1 << (HLOG)]; # endif #endif +#if ULTRA_FAST +# if defined(VERY_FAST) +# undef VERY_FAST +# endif +#endif + #if USE_MEMCPY || INIT_HTAB # ifdef __cplusplus # include <cstring> @@ -46,8 +46,8 @@ * the hashing function might seem strange, just believe me * it works ;) */ -#define FRST(p) (((p[0]) << 8) + p[1]) -#define NEXT(v,p) (((v) << 8) + p[2]) +#define FRST(p) (((p[0]) << 8) | p[1]) +#define NEXT(v,p) (((v) << 8) | p[2]) #define IDX(h) ((((h ^ (h << 5)) >> (3*8 - HLOG)) - h*5) & (HSIZE - 1)) /* * IDX works because it is very similar to a multiplicative hash, e.g. @@ -139,13 +139,13 @@ lzf_compress (const void *const in_data, unsigned int in_len, unsigned int maxlen = in_end - ip - len; maxlen = maxlen > MAX_REF ? MAX_REF : maxlen; + if (op + lit + 1 + 3 >= out_end) + return 0; + do len++; while (len < maxlen && ref[len] == ip[len]); - if (op + lit + 1 + 3 >= out_end) - return 0; - if (lit) { *op++ = lit - 1; @@ -170,12 +170,22 @@ lzf_compress (const void *const in_data, unsigned int in_len, *op++ = off; -#if ULTRA_FAST +#if ULTRA_FAST || VERY_FAST ip += len; +#if VERY_FAST && !ULTRA_FAST + --ip; +#endif hval = FRST (ip); + + hval = NEXT (hval, ip); + htab[IDX (hval)] = ip; + ip++; + +#if VERY_FAST && !ULTRA_FAST hval = NEXT (hval, ip); htab[IDX (hval)] = ip; ip++; +#endif #else do { |