]>
Commit | Line | Data |
---|---|---|
7c673cae FG |
1 | /* inffas8664.c is a hand tuned assembler version of inffast.c - fast decoding |
2 | * version for AMD64 on Windows using Microsoft C compiler | |
3 | * | |
4 | * Copyright (C) 1995-2003 Mark Adler | |
5 | * For conditions of distribution and use, see copyright notice in zlib.h | |
6 | * | |
7 | * Copyright (C) 2003 Chris Anderson <christop@charm.net> | |
8 | * Please use the copyright conditions above. | |
9 | * | |
10 | * 2005 - Adaptation to Microsoft C Compiler for AMD64 by Gilles Vollant | |
11 | * | |
12 | * inffas8664.c call function inffas8664fnc in inffasx64.asm | |
13 | * inffasx64.asm is automatically convert from AMD64 portion of inffas86.c | |
14 | * | |
15 | * Dec-29-2003 -- I added AMD64 inflate asm support. This version is also | |
16 | * slightly quicker on x86 systems because, instead of using rep movsb to copy | |
17 | * data, it uses rep movsw, which moves data in 2-byte chunks instead of single | |
18 | * bytes. I've tested the AMD64 code on a Fedora Core 1 + the x86_64 updates | |
19 | * from http://fedora.linux.duke.edu/fc1_x86_64 | |
20 | * which is running on an Athlon 64 3000+ / Gigabyte GA-K8VT800M system with | |
21 | * 1GB ram. The 64-bit version is about 4% faster than the 32-bit version, | |
22 | * when decompressing mozilla-source-1.3.tar.gz. | |
23 | * | |
24 | * Mar-13-2003 -- Most of this is derived from inffast.S which is derived from | |
25 | * the gcc -S output of zlib-1.2.0/inffast.c. Zlib-1.2.0 is in beta release at | |
26 | * the moment. I have successfully compiled and tested this code with gcc2.96, | |
27 | * gcc3.2, icc5.0, msvc6.0. It is very close to the speed of inffast.S | |
28 | * compiled with gcc -DNO_MMX, but inffast.S is still faster on the P3 with MMX | |
29 | * enabled. I will attempt to merge the MMX code into this version. Newer | |
30 | * versions of this and inffast.S can be found at | |
31 | * http://www.eetbeetee.com/zlib/ and http://www.charm.net/~christop/zlib/ | |
32 | * | |
33 | */ | |
34 | ||
35 | #include <stdio.h> | |
36 | #include "zutil.h" | |
37 | #include "inftrees.h" | |
38 | #include "inflate.h" | |
39 | #include "inffast.h" | |
40 | ||
41 | /* Mark Adler's comments from inffast.c: */ | |
42 | ||
43 | /* | |
44 | Decode literal, length, and distance codes and write out the resulting | |
45 | literal and match bytes until either not enough input or output is | |
46 | available, an end-of-block is encountered, or a data error is encountered. | |
47 | When large enough input and output buffers are supplied to inflate(), for | |
48 | example, a 16K input buffer and a 64K output buffer, more than 95% of the | |
49 | inflate execution time is spent in this routine. | |
50 | ||
51 | Entry assumptions: | |
52 | ||
53 | state->mode == LEN | |
54 | strm->avail_in >= 6 | |
55 | strm->avail_out >= 258 | |
56 | start >= strm->avail_out | |
57 | state->bits < 8 | |
58 | ||
59 | On return, state->mode is one of: | |
60 | ||
61 | LEN -- ran out of enough output space or enough available input | |
62 | TYPE -- reached end of block code, inflate() to interpret next block | |
63 | BAD -- error in block data | |
64 | ||
65 | Notes: | |
66 | ||
67 | - The maximum input bits used by a length/distance pair is 15 bits for the | |
68 | length code, 5 bits for the length extra, 15 bits for the distance code, | |
69 | and 13 bits for the distance extra. This totals 48 bits, or six bytes. | |
70 | Therefore if strm->avail_in >= 6, then there is enough input to avoid | |
71 | checking for available input while decoding. | |
72 | ||
73 | - The maximum bytes that a single length/distance pair can output is 258 | |
74 | bytes, which is the maximum length that can be coded. inflate_fast() | |
75 | requires strm->avail_out >= 258 for each loop to avoid checking for | |
76 | output space. | |
77 | */ | |
78 | ||
79 | ||
80 | ||
81 | typedef struct inffast_ar { | |
82 | /* 64 32 x86 x86_64 */ | |
83 | /* ar offset register */ | |
84 | /* 0 0 */ void *esp; /* esp save */ | |
85 | /* 8 4 */ void *ebp; /* ebp save */ | |
86 | /* 16 8 */ unsigned char FAR *in; /* esi rsi local strm->next_in */ | |
87 | /* 24 12 */ unsigned char FAR *last; /* r9 while in < last */ | |
88 | /* 32 16 */ unsigned char FAR *out; /* edi rdi local strm->next_out */ | |
89 | /* 40 20 */ unsigned char FAR *beg; /* inflate()'s init next_out */ | |
90 | /* 48 24 */ unsigned char FAR *end; /* r10 while out < end */ | |
91 | /* 56 28 */ unsigned char FAR *window;/* size of window, wsize!=0 */ | |
92 | /* 64 32 */ code const FAR *lcode; /* ebp rbp local strm->lencode */ | |
93 | /* 72 36 */ code const FAR *dcode; /* r11 local strm->distcode */ | |
94 | /* 80 40 */ size_t /*unsigned long */hold; /* edx rdx local strm->hold */ | |
95 | /* 88 44 */ unsigned bits; /* ebx rbx local strm->bits */ | |
96 | /* 92 48 */ unsigned wsize; /* window size */ | |
97 | /* 96 52 */ unsigned write; /* window write index */ | |
98 | /*100 56 */ unsigned lmask; /* r12 mask for lcode */ | |
99 | /*104 60 */ unsigned dmask; /* r13 mask for dcode */ | |
100 | /*108 64 */ unsigned len; /* r14 match length */ | |
101 | /*112 68 */ unsigned dist; /* r15 match distance */ | |
102 | /*116 72 */ unsigned status; /* set when state chng*/ | |
103 | } type_ar; | |
104 | #ifdef ASMINF | |
105 | ||
106 | void inflate_fast(strm, start) | |
107 | z_streamp strm; | |
108 | unsigned start; /* inflate()'s starting value for strm->avail_out */ | |
109 | { | |
110 | struct inflate_state FAR *state; | |
111 | type_ar ar; | |
112 | void inffas8664fnc(struct inffast_ar * par); | |
113 | ||
114 | ||
115 | ||
116 | #if (defined( __GNUC__ ) && defined( __amd64__ ) && ! defined( __i386 )) || (defined(_MSC_VER) && defined(_M_AMD64)) | |
117 | #define PAD_AVAIL_IN 6 | |
118 | #define PAD_AVAIL_OUT 258 | |
119 | #else | |
120 | #define PAD_AVAIL_IN 5 | |
121 | #define PAD_AVAIL_OUT 257 | |
122 | #endif | |
123 | ||
124 | /* copy state to local variables */ | |
125 | state = (struct inflate_state FAR *)strm->state; | |
126 | ||
127 | ar.in = strm->next_in; | |
128 | ar.last = ar.in + (strm->avail_in - PAD_AVAIL_IN); | |
129 | ar.out = strm->next_out; | |
130 | ar.beg = ar.out - (start - strm->avail_out); | |
131 | ar.end = ar.out + (strm->avail_out - PAD_AVAIL_OUT); | |
132 | ar.wsize = state->wsize; | |
133 | ar.write = state->wnext; | |
134 | ar.window = state->window; | |
135 | ar.hold = state->hold; | |
136 | ar.bits = state->bits; | |
137 | ar.lcode = state->lencode; | |
138 | ar.dcode = state->distcode; | |
139 | ar.lmask = (1U << state->lenbits) - 1; | |
140 | ar.dmask = (1U << state->distbits) - 1; | |
141 | ||
142 | /* decode literals and length/distances until end-of-block or not enough | |
143 | input data or output space */ | |
144 | ||
145 | /* align in on 1/2 hold size boundary */ | |
146 | while (((size_t)(void *)ar.in & (sizeof(ar.hold) / 2 - 1)) != 0) { | |
147 | ar.hold += (unsigned long)*ar.in++ << ar.bits; | |
148 | ar.bits += 8; | |
149 | } | |
150 | ||
151 | inffas8664fnc(&ar); | |
152 | ||
153 | if (ar.status > 1) { | |
154 | if (ar.status == 2) | |
155 | strm->msg = "invalid literal/length code"; | |
156 | else if (ar.status == 3) | |
157 | strm->msg = "invalid distance code"; | |
158 | else | |
159 | strm->msg = "invalid distance too far back"; | |
160 | state->mode = BAD; | |
161 | } | |
162 | else if ( ar.status == 1 ) { | |
163 | state->mode = TYPE; | |
164 | } | |
165 | ||
166 | /* return unused bytes (on entry, bits < 8, so in won't go too far back) */ | |
167 | ar.len = ar.bits >> 3; | |
168 | ar.in -= ar.len; | |
169 | ar.bits -= ar.len << 3; | |
170 | ar.hold &= (1U << ar.bits) - 1; | |
171 | ||
172 | /* update state and return */ | |
173 | strm->next_in = ar.in; | |
174 | strm->next_out = ar.out; | |
175 | strm->avail_in = (unsigned)(ar.in < ar.last ? | |
176 | PAD_AVAIL_IN + (ar.last - ar.in) : | |
177 | PAD_AVAIL_IN - (ar.in - ar.last)); | |
178 | strm->avail_out = (unsigned)(ar.out < ar.end ? | |
179 | PAD_AVAIL_OUT + (ar.end - ar.out) : | |
180 | PAD_AVAIL_OUT - (ar.out - ar.end)); | |
181 | state->hold = (unsigned long)ar.hold; | |
182 | state->bits = ar.bits; | |
183 | return; | |
184 | } | |
185 | ||
186 | #endif |