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 (at) 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 187
