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/* inffas8664.c is a hand tuned assembler version of inffast.c - fast decoding |
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* version for AMD64 on Windows using Microsoft C compiler |
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* |
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* Copyright (C) 1995-2003 Mark Adler |
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* For conditions of distribution and use, see copyright notice in zlib.h |
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* |
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* Copyright (C) 2003 Chris Anderson <christop@charm.net> |
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* Please use the copyright conditions above. |
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* |
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* 2005 - Adaptation to Microsoft C Compiler for AMD64 by Gilles Vollant |
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* |
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* inffas8664.c call function inffas8664fnc in inffasx64.asm |
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* inffasx64.asm is automatically convert from AMD64 portion of inffas86.c |
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* |
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* Dec-29-2003 -- I added AMD64 inflate asm support. This version is also |
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* slightly quicker on x86 systems because, instead of using rep movsb to copy |
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* data, it uses rep movsw, which moves data in 2-byte chunks instead of single |
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* bytes. I've tested the AMD64 code on a Fedora Core 1 + the x86_64 updates |
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* from http://fedora.linux.duke.edu/fc1_x86_64 |
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* which is running on an Athlon 64 3000+ / Gigabyte GA-K8VT800M system with |
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* 1GB ram. The 64-bit version is about 4% faster than the 32-bit version, |
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* when decompressing mozilla-source-1.3.tar.gz. |
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* |
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* Mar-13-2003 -- Most of this is derived from inffast.S which is derived from |
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* the gcc -S output of zlib-1.2.0/inffast.c. Zlib-1.2.0 is in beta release at |
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* the moment. I have successfully compiled and tested this code with gcc2.96, |
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* gcc3.2, icc5.0, msvc6.0. It is very close to the speed of inffast.S |
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* compiled with gcc -DNO_MMX, but inffast.S is still faster on the P3 with MMX |
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* enabled. I will attempt to merge the MMX code into this version. Newer |
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* versions of this and inffast.S can be found at |
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* http://www.eetbeetee.com/zlib/ and http://www.charm.net/~christop/zlib/ |
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* |
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*/ |
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|
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#include <stdio.h> |
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#include "zutil.h" |
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#include "inftrees.h" |
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#include "inflate.h" |
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#include "inffast.h" |
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|
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/* Mark Adler's comments from inffast.c: */ |
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|
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/* |
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Decode literal, length, and distance codes and write out the resulting |
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literal and match bytes until either not enough input or output is |
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available, an end-of-block is encountered, or a data error is encountered. |
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When large enough input and output buffers are supplied to inflate(), for |
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example, a 16K input buffer and a 64K output buffer, more than 95% of the |
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inflate execution time is spent in this routine. |
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|
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Entry assumptions: |
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|
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state->mode == LEN |
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strm->avail_in >= 6 |
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strm->avail_out >= 258 |
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start >= strm->avail_out |
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state->bits < 8 |
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|
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On return, state->mode is one of: |
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|
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LEN -- ran out of enough output space or enough available input |
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TYPE -- reached end of block code, inflate() to interpret next block |
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BAD -- error in block data |
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|
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Notes: |
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|
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- The maximum input bits used by a length/distance pair is 15 bits for the |
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length code, 5 bits for the length extra, 15 bits for the distance code, |
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and 13 bits for the distance extra. This totals 48 bits, or six bytes. |
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Therefore if strm->avail_in >= 6, then there is enough input to avoid |
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checking for available input while decoding. |
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|
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- The maximum bytes that a single length/distance pair can output is 258 |
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bytes, which is the maximum length that can be coded. inflate_fast() |
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requires strm->avail_out >= 258 for each loop to avoid checking for |
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output space. |
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*/ |
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|
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|
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|
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typedef struct inffast_ar { |
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/* 64 32 x86 x86_64 */ |
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/* ar offset register */ |
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/* 0 0 */ void *esp; /* esp save */ |
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/* 8 4 */ void *ebp; /* ebp save */ |
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/* 16 8 */ unsigned char FAR *in; /* esi rsi local strm->next_in */ |
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/* 24 12 */ unsigned char FAR *last; /* r9 while in < last */ |
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/* 32 16 */ unsigned char FAR *out; /* edi rdi local strm->next_out */ |
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/* 40 20 */ unsigned char FAR *beg; /* inflate()'s init next_out */ |
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/* 48 24 */ unsigned char FAR *end; /* r10 while out < end */ |
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/* 56 28 */ unsigned char FAR *window;/* size of window, wsize!=0 */ |
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/* 64 32 */ code const FAR *lcode; /* ebp rbp local strm->lencode */ |
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/* 72 36 */ code const FAR *dcode; /* r11 local strm->distcode */ |
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/* 80 40 */ size_t /*unsigned long */hold; /* edx rdx local strm->hold */ |
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/* 88 44 */ unsigned bits; /* ebx rbx local strm->bits */ |
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/* 92 48 */ unsigned wsize; /* window size */ |
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/* 96 52 */ unsigned write; /* window write index */ |
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/*100 56 */ unsigned lmask; /* r12 mask for lcode */ |
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/*104 60 */ unsigned dmask; /* r13 mask for dcode */ |
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/*108 64 */ unsigned len; /* r14 match length */ |
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/*112 68 */ unsigned dist; /* r15 match distance */ |
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/*116 72 */ unsigned status; /* set when state chng*/ |
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} type_ar; |
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#ifdef ASMINF |
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|
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void inflate_fast(strm, start) |
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z_streamp strm; |
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unsigned start; /* inflate()'s starting value for strm->avail_out */ |
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{ |
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struct inflate_state FAR *state; |
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type_ar ar; |
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void inffas8664fnc(struct inffast_ar * par); |
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|
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|
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|
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#if (defined( __GNUC__ ) && defined( __amd64__ ) && ! defined( __i386 )) || (defined(_MSC_VER) && defined(_M_AMD64)) |
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#define PAD_AVAIL_IN 6 |
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#define PAD_AVAIL_OUT 258 |
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#else |
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#define PAD_AVAIL_IN 5 |
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#define PAD_AVAIL_OUT 257 |
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#endif |
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|
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/* copy state to local variables */ |
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state = (struct inflate_state FAR *)strm->state; |
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|
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ar.in = strm->next_in; |
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ar.last = ar.in + (strm->avail_in - PAD_AVAIL_IN); |
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ar.out = strm->next_out; |
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ar.beg = ar.out - (start - strm->avail_out); |
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ar.end = ar.out + (strm->avail_out - PAD_AVAIL_OUT); |
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ar.wsize = state->wsize; |
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ar.write = state->wnext; |
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ar.window = state->window; |
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ar.hold = state->hold; |
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ar.bits = state->bits; |
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ar.lcode = state->lencode; |
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ar.dcode = state->distcode; |
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ar.lmask = (1U << state->lenbits) - 1; |
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ar.dmask = (1U << state->distbits) - 1; |
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|
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/* decode literals and length/distances until end-of-block or not enough |
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input data or output space */ |
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|
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/* align in on 1/2 hold size boundary */ |
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while (((size_t)(void *)ar.in & (sizeof(ar.hold) / 2 - 1)) != 0) { |
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ar.hold += (unsigned long)*ar.in++ << ar.bits; |
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ar.bits += 8; |
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} |
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|
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inffas8664fnc(&ar); |
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|
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if (ar.status > 1) { |
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if (ar.status == 2) |
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strm->msg = "invalid literal/length code"; |
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else if (ar.status == 3) |
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strm->msg = "invalid distance code"; |
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else |
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strm->msg = "invalid distance too far back"; |
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state->mode = BAD; |
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} |
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else if ( ar.status == 1 ) { |
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state->mode = TYPE; |
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} |
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|
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/* return unused bytes (on entry, bits < 8, so in won't go too far back) */ |
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ar.len = ar.bits >> 3; |
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ar.in -= ar.len; |
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ar.bits -= ar.len << 3; |
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ar.hold &= (1U << ar.bits) - 1; |
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|
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/* update state and return */ |
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strm->next_in = ar.in; |
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strm->next_out = ar.out; |
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strm->avail_in = (unsigned)(ar.in < ar.last ? |
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PAD_AVAIL_IN + (ar.last - ar.in) : |
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PAD_AVAIL_IN - (ar.in - ar.last)); |
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strm->avail_out = (unsigned)(ar.out < ar.end ? |
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PAD_AVAIL_OUT + (ar.end - ar.out) : |
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PAD_AVAIL_OUT - (ar.out - ar.end)); |
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state->hold = (unsigned long)ar.hold; |
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state->bits = ar.bits; |
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return; |
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} |
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|
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#endif |
