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783 lines
25 KiB
783 lines
25 KiB
/* inffas86.c is a hand tuned assembler version of |
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* |
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* inffast.c -- fast decoding |
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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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* 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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#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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/* Mark Adler's comments from inffast.c: */ |
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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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Entry assumptions: |
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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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On return, state->mode is one of: |
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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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Notes: |
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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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- 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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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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struct inffast_ar { |
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void *esp; /* esp save */ |
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unsigned char FAR *in; /* local strm->next_in */ |
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unsigned char FAR *last; /* while in < last, enough input available */ |
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unsigned char FAR *out; /* local strm->next_out */ |
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unsigned char FAR *beg; /* inflate()'s initial strm->next_out */ |
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unsigned char FAR *end; /* while out < end, enough space available */ |
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unsigned wsize; /* window size or zero if not using window */ |
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unsigned write; /* window write index */ |
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unsigned char FAR *window; /* allocated sliding window, if wsize != 0 */ |
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unsigned long hold; /* local strm->hold */ |
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unsigned bits; /* local strm->bits */ |
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code const FAR *lcode; /* local strm->lencode */ |
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code const FAR *dcode; /* local strm->distcode */ |
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unsigned lmask; /* mask for first level of length codes */ |
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unsigned dmask; /* mask for first level of distance codes */ |
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unsigned len; /* match length, unused bytes */ |
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unsigned dist; /* match distance */ |
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unsigned status; /* this is set when state changes */ |
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} ar; |
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/* copy state to local variables */ |
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state = (struct inflate_state FAR *)strm->state; |
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ar.in = strm->next_in; |
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ar.last = ar.in + (strm->avail_in - 5); |
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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 - 257); |
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ar.wsize = state->wsize; |
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ar.write = state->write; |
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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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/* 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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/* align in on 2 byte boundary */ |
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if (((unsigned long)(void *)ar.in & 0x1) != 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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#if defined( __GNUC__ ) || defined( __ICC ) |
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__asm__ __volatile__ ( |
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" leal %0, %%eax\n" |
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" pushf\n" |
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" pushl %%ebp\n" |
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" movl %%esp, (%%eax)\n" |
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" movl %%eax, %%esp\n" |
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" movl 4(%%esp), %%esi\n" /* esi = in */ |
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" movl 12(%%esp), %%edi\n" /* edi = out */ |
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" movl 36(%%esp), %%edx\n" /* edx = hold */ |
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" movl 40(%%esp), %%ebx\n" /* ebx = bits */ |
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" movl 44(%%esp), %%ebp\n" /* ebp = lcode */ |
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|
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" cld\n" |
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" jmp .L_do_loop\n" |
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".L_while_test:\n" |
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" cmpl %%edi, 20(%%esp)\n" |
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" jbe .L_break_loop\n" |
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" cmpl %%esi, 8(%%esp)\n" |
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" jbe .L_break_loop\n" |
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".L_do_loop:\n" |
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" cmpb $15, %%bl\n" |
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" ja .L_get_length_code\n" /* if (15 < bits) */ |
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|
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" xorl %%eax, %%eax\n" |
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" lodsw\n" /* al = *(ushort *)in++ */ |
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" movb %%bl, %%cl\n" /* cl = bits, needs it for shifting */ |
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" addb $16, %%bl\n" /* bits += 16 */ |
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" shll %%cl, %%eax\n" |
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" orl %%eax, %%edx\n" /* hold |= *((ushort *)in)++ << bits */ |
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".L_get_length_code:\n" |
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" movl 52(%%esp), %%eax\n" /* eax = lmask */ |
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" andl %%edx, %%eax\n" /* eax &= hold */ |
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" movl (%%ebp,%%eax,4), %%eax\n" /* eax = lcode[hold & lmask] */ |
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".L_dolen:\n" |
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" movb %%ah, %%cl\n" /* cl = this.bits */ |
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" subb %%ah, %%bl\n" /* bits -= this.bits */ |
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" shrl %%cl, %%edx\n" /* hold >>= this.bits */ |
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|
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" testb %%al, %%al\n" |
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" jnz .L_test_for_length_base\n" /* if (op != 0) 45.7% */ |
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|
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" shrl $16, %%eax\n" /* output this.val char */ |
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" stosb\n" |
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" jmp .L_while_test\n" |
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".L_test_for_length_base:\n" |
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" movl %%eax, %%ecx\n" /* len = this */ |
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" shrl $16, %%ecx\n" /* len = this.val */ |
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" movl %%ecx, 60(%%esp)\n" /* len = this */ |
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" movb %%al, %%cl\n" |
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|
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" testb $16, %%al\n" |
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" jz .L_test_for_second_level_length\n" /* if ((op & 16) == 0) 8% */ |
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" andb $15, %%cl\n" /* op &= 15 */ |
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" jz .L_decode_distance\n" /* if (!op) */ |
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" cmpb %%cl, %%bl\n" |
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" jae .L_add_bits_to_len\n" /* if (op <= bits) */ |
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|
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" movb %%cl, %%ch\n" /* stash op in ch, freeing cl */ |
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" xorl %%eax, %%eax\n" |
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" lodsw\n" /* al = *(ushort *)in++ */ |
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" movb %%bl, %%cl\n" /* cl = bits, needs it for shifting */ |
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" addb $16, %%bl\n" /* bits += 16 */ |
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" shll %%cl, %%eax\n" |
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" orl %%eax, %%edx\n" /* hold |= *((ushort *)in)++ << bits */ |
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" movb %%ch, %%cl\n" /* move op back to ecx */ |
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".L_add_bits_to_len:\n" |
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" movl $1, %%eax\n" |
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" shll %%cl, %%eax\n" |
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" decl %%eax\n" |
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" subb %%cl, %%bl\n" |
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" andl %%edx, %%eax\n" /* eax &= hold */ |
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" shrl %%cl, %%edx\n" |
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" addl %%eax, 60(%%esp)\n" /* len += hold & mask[op] */ |
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".L_decode_distance:\n" |
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" cmpb $15, %%bl\n" |
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" ja .L_get_distance_code\n" /* if (15 < bits) */ |
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|
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" xorl %%eax, %%eax\n" |
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" lodsw\n" /* al = *(ushort *)in++ */ |
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" movb %%bl, %%cl\n" /* cl = bits, needs it for shifting */ |
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" addb $16, %%bl\n" /* bits += 16 */ |
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" shll %%cl, %%eax\n" |
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" orl %%eax, %%edx\n" /* hold |= *((ushort *)in)++ << bits */ |
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".L_get_distance_code:\n" |
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" movl 56(%%esp), %%eax\n" /* eax = dmask */ |
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" movl 48(%%esp), %%ecx\n" /* ecx = dcode */ |
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" andl %%edx, %%eax\n" /* eax &= hold */ |
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" movl (%%ecx,%%eax,4), %%eax\n"/* eax = dcode[hold & dmask] */ |
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".L_dodist:\n" |
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" movl %%eax, %%ebp\n" /* dist = this */ |
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" shrl $16, %%ebp\n" /* dist = this.val */ |
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" movb %%ah, %%cl\n" |
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" subb %%ah, %%bl\n" /* bits -= this.bits */ |
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" shrl %%cl, %%edx\n" /* hold >>= this.bits */ |
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" movb %%al, %%cl\n" /* cl = this.op */ |
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|
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" testb $16, %%al\n" /* if ((op & 16) == 0) */ |
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" jz .L_test_for_second_level_dist\n" |
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" andb $15, %%cl\n" /* op &= 15 */ |
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" jz .L_check_dist_one\n" |
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" cmpb %%cl, %%bl\n" |
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" jae .L_add_bits_to_dist\n" /* if (op <= bits) 97.6% */ |
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|
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" movb %%cl, %%ch\n" /* stash op in ch, freeing cl */ |
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" xorl %%eax, %%eax\n" |
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" lodsw\n" /* al = *(ushort *)in++ */ |
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" movb %%bl, %%cl\n" /* cl = bits, needs it for shifting */ |
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" addb $16, %%bl\n" /* bits += 16 */ |
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" shll %%cl, %%eax\n" |
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" orl %%eax, %%edx\n" /* hold |= *((ushort *)in)++ << bits */ |
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" movb %%ch, %%cl\n" /* move op back to ecx */ |
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".L_add_bits_to_dist:\n" |
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" movl $1, %%eax\n" |
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" shll %%cl, %%eax\n" |
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" decl %%eax\n" /* (1 << op) - 1 */ |
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" subb %%cl, %%bl\n" |
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" andl %%edx, %%eax\n" /* eax &= hold */ |
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" shrl %%cl, %%edx\n" |
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" addl %%eax, %%ebp\n" /* dist += hold & ((1 << op) - 1) */ |
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".L_check_window:\n" |
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" movl %%esi, 4(%%esp)\n" /* save in so from can use it's reg */ |
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" movl %%edi, %%eax\n" |
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" subl 16(%%esp), %%eax\n" /* nbytes = out - beg */ |
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|
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" cmpl %%ebp, %%eax\n" |
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" jb .L_clip_window\n" /* if (dist > nbytes) 4.2% */ |
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|
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" movl 60(%%esp), %%ecx\n" |
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" movl %%edi, %%esi\n" |
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" subl %%ebp, %%esi\n" /* from = out - dist */ |
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|
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" subl $3, %%ecx\n" /* copy from to out */ |
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" movb (%%esi), %%al\n" |
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" movb %%al, (%%edi)\n" |
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" movb 1(%%esi), %%al\n" |
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" movb 2(%%esi), %%ah\n" |
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" addl $3, %%esi\n" |
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" movb %%al, 1(%%edi)\n" |
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" movb %%ah, 2(%%edi)\n" |
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" addl $3, %%edi\n" |
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" rep movsb\n" |
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|
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" movl 4(%%esp), %%esi\n" /* move in back to %esi, toss from */ |
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" movl 44(%%esp), %%ebp\n" /* ebp = lcode */ |
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" jmp .L_while_test\n" |
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".L_check_dist_one:\n" |
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" cmpl $1, %%ebp\n" /* if dist 1, is a memset */ |
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" jne .L_check_window\n" |
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" cmpl %%edi, 16(%%esp)\n" |
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" je .L_check_window\n" |
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|
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" decl %%edi\n" |
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" movl 60(%%esp), %%ecx\n" |
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" movb (%%edi), %%al\n" |
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" subl $3, %%ecx\n" |
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|
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" movb %%al, 1(%%edi)\n" /* memset out with from[-1] */ |
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" movb %%al, 2(%%edi)\n" |
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" movb %%al, 3(%%edi)\n" |
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" addl $4, %%edi\n" |
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" rep stosb\n" |
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" movl 44(%%esp), %%ebp\n" /* ebp = lcode */ |
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" jmp .L_while_test\n" |
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".L_test_for_second_level_length:\n" |
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" testb $64, %%al\n" |
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" jnz .L_test_for_end_of_block\n" /* if ((op & 64) != 0) */ |
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|
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" movl $1, %%eax\n" |
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" shll %%cl, %%eax\n" |
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" decl %%eax\n" |
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" andl %%edx, %%eax\n" /* eax &= hold */ |
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" addl 60(%%esp), %%eax\n" /* eax += this.val */ |
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" movl (%%ebp,%%eax,4), %%eax\n" /* eax = lcode[val+(hold&mask[op])]*/ |
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" jmp .L_dolen\n" |
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".L_test_for_second_level_dist:\n" |
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" testb $64, %%al\n" |
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" jnz .L_invalid_distance_code\n" /* if ((op & 64) != 0) */ |
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|
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" movl $1, %%eax\n" |
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" shll %%cl, %%eax\n" |
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" decl %%eax\n" |
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" andl %%edx, %%eax\n" /* eax &= hold */ |
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" addl %%ebp, %%eax\n" /* eax += this.val */ |
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" movl 48(%%esp), %%ecx\n" /* ecx = dcode */ |
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" movl (%%ecx,%%eax,4), %%eax\n" /* eax = dcode[val+(hold&mask[op])]*/ |
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" jmp .L_dodist\n" |
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".L_clip_window:\n" |
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" movl %%eax, %%ecx\n" |
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" movl 24(%%esp), %%eax\n" /* prepare for dist compare */ |
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" negl %%ecx\n" /* nbytes = -nbytes */ |
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" movl 32(%%esp), %%esi\n" /* from = window */ |
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|
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" cmpl %%ebp, %%eax\n" |
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" jb .L_invalid_distance_too_far\n" /* if (dist > wsize) */ |
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|
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" addl %%ebp, %%ecx\n" /* nbytes = dist - nbytes */ |
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" cmpl $0, 28(%%esp)\n" |
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" jne .L_wrap_around_window\n" /* if (write != 0) */ |
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|
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" subl %%ecx, %%eax\n" |
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" addl %%eax, %%esi\n" /* from += wsize - nbytes */ |
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" movl 60(%%esp), %%eax\n" |
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" cmpl %%ecx, %%eax\n" |
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" jbe .L_do_copy1\n" /* if (nbytes >= len) */ |
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|
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" subl %%ecx, %%eax\n" /* len -= nbytes */ |
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" rep movsb\n" |
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" movl %%edi, %%esi\n" |
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" subl %%ebp, %%esi\n" /* from = out - dist */ |
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" jmp .L_do_copy1\n" |
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|
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" cmpl %%ecx, %%eax\n" |
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" jbe .L_do_copy1\n" /* if (nbytes >= len) */ |
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|
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" subl %%ecx, %%eax\n" /* len -= nbytes */ |
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" rep movsb\n" |
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" movl %%edi, %%esi\n" |
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" subl %%ebp, %%esi\n" /* from = out - dist */ |
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" jmp .L_do_copy1\n" |
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".L_wrap_around_window:\n" |
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" movl 28(%%esp), %%eax\n" |
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" cmpl %%eax, %%ecx\n" |
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" jbe .L_contiguous_in_window\n" /* if (write >= nbytes) */ |
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|
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" addl 24(%%esp), %%esi\n" |
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" addl %%eax, %%esi\n" |
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" subl %%ecx, %%esi\n" /* from += wsize + write - nbytes */ |
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" subl %%eax, %%ecx\n" /* nbytes -= write */ |
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|
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" movl 60(%%esp), %%eax\n" |
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" cmpl %%ecx, %%eax\n" |
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" jbe .L_do_copy1\n" /* if (nbytes >= len) */ |
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|
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" subl %%ecx, %%eax\n" /* len -= nbytes */ |
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" rep movsb\n" |
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" movl 32(%%esp), %%esi\n" /* from = window */ |
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" movl 28(%%esp), %%ecx\n" /* nbytes = write */ |
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" cmpl %%ecx, %%eax\n" |
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" jbe .L_do_copy1\n" /* if (nbytes >= len) */ |
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|
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" subl %%ecx, %%eax\n" /* len -= nbytes */ |
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" rep movsb\n" |
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" movl %%edi, %%esi\n" |
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" subl %%ebp, %%esi\n" /* from = out - dist */ |
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" jmp .L_do_copy1\n" |
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".L_contiguous_in_window:\n" |
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" addl %%eax, %%esi\n" |
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" subl %%ecx, %%esi\n" /* from += write - nbytes */ |
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|
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" movl 60(%%esp), %%eax\n" |
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" cmpl %%ecx, %%eax\n" |
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" jbe .L_do_copy1\n" /* if (nbytes >= len) */ |
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|
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" subl %%ecx, %%eax\n" /* len -= nbytes */ |
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" rep movsb\n" |
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" movl %%edi, %%esi\n" |
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" subl %%ebp, %%esi\n" /* from = out - dist */ |
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".L_do_copy1:\n" |
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" movl %%eax, %%ecx\n" |
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" rep movsb\n" |
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|
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" movl 4(%%esp), %%esi\n" /* move in back to %esi, toss from */ |
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" movl 44(%%esp), %%ebp\n" /* ebp = lcode */ |
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" jmp .L_while_test\n" |
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".L_test_for_end_of_block:\n" |
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" testb $32, %%al\n" |
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" jz .L_invalid_literal_length_code\n" |
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" movl $1, 68(%%esp)\n" |
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" jmp .L_break_loop_with_status\n" |
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".L_invalid_literal_length_code:\n" |
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" movl $2, 68(%%esp)\n" |
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" jmp .L_break_loop_with_status\n" |
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".L_invalid_distance_code:\n" |
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" movl $3, 68(%%esp)\n" |
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" jmp .L_break_loop_with_status\n" |
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".L_invalid_distance_too_far:\n" |
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" movl 4(%%esp), %%esi\n" |
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" movl $4, 68(%%esp)\n" |
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" jmp .L_break_loop_with_status\n" |
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".L_break_loop:\n" |
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" movl $0, 68(%%esp)\n" |
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".L_break_loop_with_status:\n" |
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/* put in, out, bits, and hold back into ar and pop esp */ |
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" movl %%esi, 4(%%esp)\n" |
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" movl %%edi, 12(%%esp)\n" |
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" movl %%ebx, 40(%%esp)\n" |
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" movl %%edx, 36(%%esp)\n" |
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" movl (%%esp), %%esp\n" |
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" popl %%ebp\n" |
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" popf\n" |
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: |
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: "m" (ar) |
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: "memory", "%eax", "%ebx", "%ecx", "%edx", "%esi", "%edi" |
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); |
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#elif defined( _MSC_VER ) |
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__asm { |
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lea eax, ar |
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pushfd |
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push ebp |
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mov [eax], esp |
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mov esp, eax |
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mov esi, [esp+4] /* esi = in */ |
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mov edi, [esp+12] /* edi = out */ |
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mov edx, [esp+36] /* edx = hold */ |
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mov ebx, [esp+40] /* ebx = bits */ |
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mov ebp, [esp+44] /* ebp = lcode */ |
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cld |
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jmp L_do_loop |
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L_while_test: |
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cmp [esp+20], edi |
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jbe L_break_loop |
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cmp [esp+8], esi |
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jbe L_break_loop |
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L_do_loop: |
|
cmp bl, 15 |
|
ja L_get_length_code /* if (15 < bits) */ |
|
|
|
xor eax, eax |
|
lodsw /* al = *(ushort *)in++ */ |
|
mov cl, bl /* cl = bits, needs it for shifting */ |
|
add bl, 16 /* bits += 16 */ |
|
shl eax, cl |
|
or edx, eax /* hold |= *((ushort *)in)++ << bits */ |
|
|
|
L_get_length_code: |
|
mov eax, [esp+52] /* eax = lmask */ |
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and eax, edx /* eax &= hold */ |
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mov eax, [ebp+eax*4] /* eax = lcode[hold & lmask] */ |
|
|
|
L_dolen: |
|
mov cl, ah /* cl = this.bits */ |
|
sub bl, ah /* bits -= this.bits */ |
|
shr edx, cl /* hold >>= this.bits */ |
|
|
|
test al, al |
|
jnz L_test_for_length_base /* if (op != 0) 45.7% */ |
|
|
|
shr eax, 16 /* output this.val char */ |
|
stosb |
|
jmp L_while_test |
|
|
|
L_test_for_length_base: |
|
mov ecx, eax /* len = this */ |
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shr ecx, 16 /* len = this.val */ |
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mov [esp+60], ecx /* len = this */ |
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mov cl, al |
|
|
|
test al, 16 |
|
jz L_test_for_second_level_length /* if ((op & 16) == 0) 8% */ |
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and cl, 15 /* op &= 15 */ |
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jz L_decode_distance /* if (!op) */ |
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cmp bl, cl |
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jae L_add_bits_to_len /* if (op <= bits) */ |
|
|
|
mov ch, cl /* stash op in ch, freeing cl */ |
|
xor eax, eax |
|
lodsw /* al = *(ushort *)in++ */ |
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mov cl, bl /* cl = bits, needs it for shifting */ |
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add bl, 16 /* bits += 16 */ |
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shl eax, cl |
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or edx, eax /* hold |= *((ushort *)in)++ << bits */ |
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mov cl, ch /* move op back to ecx */ |
|
|
|
L_add_bits_to_len: |
|
mov eax, 1 |
|
shl eax, cl |
|
dec eax |
|
sub bl, cl |
|
and eax, edx /* eax &= hold */ |
|
shr edx, cl |
|
add [esp+60], eax /* len += hold & mask[op] */ |
|
|
|
L_decode_distance: |
|
cmp bl, 15 |
|
ja L_get_distance_code /* if (15 < bits) */ |
|
|
|
xor eax, eax |
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lodsw /* al = *(ushort *)in++ */ |
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mov cl, bl /* cl = bits, needs it for shifting */ |
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add bl, 16 /* bits += 16 */ |
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shl eax, cl |
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or edx, eax /* hold |= *((ushort *)in)++ << bits */ |
|
|
|
L_get_distance_code: |
|
mov eax, [esp+56] /* eax = dmask */ |
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mov ecx, [esp+48] /* ecx = dcode */ |
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and eax, edx /* eax &= hold */ |
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mov eax, [ecx+eax*4]/* eax = dcode[hold & dmask] */ |
|
|
|
L_dodist: |
|
mov ebp, eax /* dist = this */ |
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shr ebp, 16 /* dist = this.val */ |
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mov cl, ah |
|
sub bl, ah /* bits -= this.bits */ |
|
shr edx, cl /* hold >>= this.bits */ |
|
mov cl, al /* cl = this.op */ |
|
|
|
test al, 16 /* if ((op & 16) == 0) */ |
|
jz L_test_for_second_level_dist |
|
and cl, 15 /* op &= 15 */ |
|
jz L_check_dist_one |
|
cmp bl, cl |
|
jae L_add_bits_to_dist /* if (op <= bits) 97.6% */ |
|
|
|
mov ch, cl /* stash op in ch, freeing cl */ |
|
xor eax, eax |
|
lodsw /* al = *(ushort *)in++ */ |
|
mov cl, bl /* cl = bits, needs it for shifting */ |
|
add bl, 16 /* bits += 16 */ |
|
shl eax, cl |
|
or edx, eax /* hold |= *((ushort *)in)++ << bits */ |
|
mov cl, ch /* move op back to ecx */ |
|
|
|
L_add_bits_to_dist: |
|
mov eax, 1 |
|
shl eax, cl |
|
dec eax /* (1 << op) - 1 */ |
|
sub bl, cl |
|
and eax, edx /* eax &= hold */ |
|
shr edx, cl |
|
add ebp, eax /* dist += hold & ((1 << op) - 1) */ |
|
|
|
L_check_window: |
|
mov [esp+4], esi /* save in so from can use it's reg */ |
|
mov eax, edi |
|
sub eax, [esp+16] /* nbytes = out - beg */ |
|
|
|
cmp eax, ebp |
|
jb L_clip_window /* if (dist > nbytes) 4.2% */ |
|
|
|
mov ecx, [esp+60] |
|
mov esi, edi |
|
sub esi, ebp /* from = out - dist */ |
|
|
|
sub ecx, 3 /* copy from to out */ |
|
mov al, [esi] |
|
mov [edi], al |
|
mov al, [esi+1] |
|
mov ah, [esi+2] |
|
add esi, 3 |
|
mov [edi+1], al |
|
mov [edi+2], ah |
|
add edi, 3 |
|
rep movsb |
|
|
|
mov esi, [esp+4] /* move in back to %esi, toss from */ |
|
mov ebp, [esp+44] /* ebp = lcode */ |
|
jmp L_while_test |
|
|
|
L_check_dist_one: |
|
cmp ebp, 1 /* if dist 1, is a memset */ |
|
jne L_check_window |
|
cmp [esp+16], edi |
|
je L_check_window |
|
|
|
dec edi |
|
mov ecx, [esp+60] |
|
mov al, [edi] |
|
sub ecx, 3 |
|
|
|
mov [edi+1], al /* memset out with from[-1] */ |
|
mov [edi+2], al |
|
mov [edi+3], al |
|
add edi, 4 |
|
rep stosb |
|
mov ebp, [esp+44] /* ebp = lcode */ |
|
jmp L_while_test |
|
|
|
L_test_for_second_level_length: |
|
test al, 64 |
|
jnz L_test_for_end_of_block /* if ((op & 64) != 0) */ |
|
|
|
mov eax, 1 |
|
shl eax, cl |
|
dec eax |
|
and eax, edx /* eax &= hold */ |
|
add eax, [esp+60] /* eax += this.val */ |
|
mov eax, [ebp+eax*4] /* eax = lcode[val+(hold&mask[op])]*/ |
|
jmp L_dolen |
|
|
|
L_test_for_second_level_dist: |
|
test al, 64 |
|
jnz L_invalid_distance_code /* if ((op & 64) != 0) */ |
|
|
|
mov eax, 1 |
|
shl eax, cl |
|
dec eax |
|
and eax, edx /* eax &= hold */ |
|
add eax, ebp /* eax += this.val */ |
|
mov ecx, [esp+48] /* ecx = dcode */ |
|
mov eax, [ecx+eax*4] /* eax = dcode[val+(hold&mask[op])]*/ |
|
jmp L_dodist |
|
|
|
L_clip_window: |
|
mov ecx, eax |
|
mov eax, [esp+24] /* prepare for dist compare */ |
|
neg ecx /* nbytes = -nbytes */ |
|
mov esi, [esp+32] /* from = window */ |
|
|
|
cmp eax, ebp |
|
jb L_invalid_distance_too_far /* if (dist > wsize) */ |
|
|
|
add ecx, ebp /* nbytes = dist - nbytes */ |
|
cmp dword ptr [esp+28], 0 |
|
jne L_wrap_around_window /* if (write != 0) */ |
|
|
|
sub eax, ecx |
|
add esi, eax /* from += wsize - nbytes */ |
|
|
|
mov eax, [esp+60] |
|
cmp eax, ecx |
|
jbe L_do_copy1 /* if (nbytes >= len) */ |
|
|
|
sub eax, ecx /* len -= nbytes */ |
|
rep movsb |
|
mov esi, edi |
|
sub esi, ebp /* from = out - dist */ |
|
jmp L_do_copy1 |
|
|
|
cmp eax, ecx |
|
jbe L_do_copy1 /* if (nbytes >= len) */ |
|
|
|
sub eax, ecx /* len -= nbytes */ |
|
rep movsb |
|
mov esi, edi |
|
sub esi, ebp /* from = out - dist */ |
|
jmp L_do_copy1 |
|
|
|
L_wrap_around_window: |
|
mov eax, [esp+28] |
|
cmp ecx, eax |
|
jbe L_contiguous_in_window /* if (write >= nbytes) */ |
|
|
|
add esi, [esp+24] |
|
add esi, eax |
|
sub esi, ecx /* from += wsize + write - nbytes */ |
|
sub ecx, eax /* nbytes -= write */ |
|
|
|
mov eax, [esp+60] |
|
cmp eax, ecx |
|
jbe L_do_copy1 /* if (nbytes >= len) */ |
|
|
|
sub eax, ecx /* len -= nbytes */ |
|
rep movsb |
|
mov esi, [esp+32] /* from = window */ |
|
mov ecx, [esp+28] /* nbytes = write */ |
|
cmp eax, ecx |
|
jbe L_do_copy1 /* if (nbytes >= len) */ |
|
|
|
sub eax, ecx /* len -= nbytes */ |
|
rep movsb |
|
mov esi, edi |
|
sub esi, ebp /* from = out - dist */ |
|
jmp L_do_copy1 |
|
|
|
L_contiguous_in_window: |
|
add esi, eax |
|
sub esi, ecx /* from += write - nbytes */ |
|
|
|
mov eax, [esp+60] |
|
cmp eax, ecx |
|
jbe L_do_copy1 /* if (nbytes >= len) */ |
|
|
|
sub eax, ecx /* len -= nbytes */ |
|
rep movsb |
|
mov esi, edi |
|
sub esi, ebp /* from = out - dist */ |
|
|
|
L_do_copy1: |
|
mov ecx, eax |
|
rep movsb |
|
|
|
mov esi, [esp+4] /* move in back to %esi, toss from */ |
|
mov ebp, [esp+44] /* ebp = lcode */ |
|
jmp L_while_test |
|
|
|
L_test_for_end_of_block: |
|
test al, 32 |
|
jz L_invalid_literal_length_code |
|
mov dword ptr [esp+68], 1 |
|
jmp L_break_loop_with_status |
|
|
|
L_invalid_literal_length_code: |
|
mov dword ptr [esp+68], 2 |
|
jmp L_break_loop_with_status |
|
|
|
L_invalid_distance_code: |
|
mov dword ptr [esp+68], 3 |
|
jmp L_break_loop_with_status |
|
|
|
L_invalid_distance_too_far: |
|
mov esi, [esp+4] |
|
mov dword ptr [esp+68], 4 |
|
jmp L_break_loop_with_status |
|
|
|
L_break_loop: |
|
mov dword ptr [esp+68], 0 |
|
|
|
L_break_loop_with_status: |
|
/* put in, out, bits, and hold back into ar and pop esp */ |
|
mov [esp+4], esi |
|
mov [esp+12], edi |
|
mov [esp+40], ebx |
|
mov [esp+36], edx |
|
mov esp, [esp] |
|
pop ebp |
|
popfd |
|
} |
|
#endif |
|
|
|
if (ar.status > 1) { |
|
if (ar.status == 2) |
|
strm->msg = "invalid literal/length code"; |
|
else if (ar.status == 3) |
|
strm->msg = "invalid distance code"; |
|
else |
|
strm->msg = "invalid distance too far back"; |
|
state->mode = BAD; |
|
} |
|
else if ( ar.status == 1 ) { |
|
state->mode = TYPE; |
|
} |
|
|
|
/* return unused bytes (on entry, bits < 8, so in won't go too far back) */ |
|
ar.len = ar.bits >> 3; |
|
ar.in -= ar.len; |
|
ar.bits -= ar.len << 3; |
|
ar.hold &= (1U << ar.bits) - 1; |
|
|
|
/* update state and return */ |
|
strm->next_in = ar.in; |
|
strm->next_out = ar.out; |
|
strm->avail_in = (unsigned)(ar.in < ar.last ? 5 + (ar.last - ar.in) : |
|
5 - (ar.in - ar.last)); |
|
strm->avail_out = (unsigned)(ar.out < ar.end ? 257 + (ar.end - ar.out) : |
|
257 - (ar.out - ar.end)); |
|
state->hold = ar.hold; |
|
state->bits = ar.bits; |
|
return; |
|
} |
|
|
|
|