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|
/* inffas86.c is a hand tuned assembler version of
*
* inffast.c -- fast decoding
* Copyright (C) 1995-2003 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*
* Copyright (C) 2003 Chris Anderson <christop@charm.net>
* Please use the copyright conditions above.
*
* Mar-13-2003 -- Most of this is derived from inffast.S which is derived from
* the gcc -S output of zlib-1.2.0/inffast.c. Zlib-1.2.0 is in beta release at
* the moment. I have successfully compiled and tested this code with gcc2.96,
* gcc3.2, icc5.0, msvc6.0. It is very close to the speed of inffast.S
* compiled with gcc -DNO_MMX, but inffast.S is still faster on the P3 with MMX
* enabled. I will attempt to merge the MMX code into this version. Newer
* versions of this and inffast.S can be found at
* http://www.eetbeetee.com/zlib/ and http://www.charm.net/~christop/zlib/
*/
#include "zutil.h"
#include "inftrees.h"
#include "inflate.h"
#include "inffast.h"
/* Mark Adler's comments from inffast.c: */
/*
Decode literal, length, and distance codes and write out the resulting
literal and match bytes until either not enough input or output is
available, an end-of-block is encountered, or a data error is encountered.
When large enough input and output buffers are supplied to inflate(), for
example, a 16K input buffer and a 64K output buffer, more than 95% of the
inflate execution time is spent in this routine.
Entry assumptions:
state->mode == LEN
strm->avail_in >= 6
strm->avail_out >= 258
start >= strm->avail_out
state->bits < 8
On return, state->mode is one of:
LEN -- ran out of enough output space or enough available input
TYPE -- reached end of block code, inflate() to interpret next block
BAD -- error in block data
Notes:
- The maximum input bits used by a length/distance pair is 15 bits for the
length code, 5 bits for the length extra, 15 bits for the distance code,
and 13 bits for the distance extra. This totals 48 bits, or six bytes.
Therefore if strm->avail_in >= 6, then there is enough input to avoid
checking for available input while decoding.
- The maximum bytes that a single length/distance pair can output is 258
bytes, which is the maximum length that can be coded. inflate_fast()
requires strm->avail_out >= 258 for each loop to avoid checking for
output space.
*/
void inflate_fast(strm, start)
z_streamp strm;
unsigned start; /* inflate()'s starting value for strm->avail_out */
{
struct inflate_state FAR *state;
struct inffast_ar {
void *esp; /* esp save */
unsigned char FAR *in; /* local strm->next_in */
unsigned char FAR *last; /* while in < last, enough input available */
unsigned char FAR *out; /* local strm->next_out */
unsigned char FAR *beg; /* inflate()'s initial strm->next_out */
unsigned char FAR *end; /* while out < end, enough space available */
unsigned wsize; /* window size or zero if not using window */
unsigned write; /* window write index */
unsigned char FAR *window; /* allocated sliding window, if wsize != 0 */
unsigned long hold; /* local strm->hold */
unsigned bits; /* local strm->bits */
code const FAR *lcode; /* local strm->lencode */
code const FAR *dcode; /* local strm->distcode */
unsigned lmask; /* mask for first level of length codes */
unsigned dmask; /* mask for first level of distance codes */
unsigned len; /* match length, unused bytes */
unsigned dist; /* match distance */
unsigned status; /* this is set when state changes */
} ar;
/* copy state to local variables */
state = (struct inflate_state FAR *)strm->state;
ar.in = strm->next_in;
ar.last = ar.in + (strm->avail_in - 5);
ar.out = strm->next_out;
ar.beg = ar.out - (start - strm->avail_out);
ar.end = ar.out + (strm->avail_out - 257);
ar.wsize = state->wsize;
ar.write = state->write;
ar.window = state->window;
ar.hold = state->hold;
ar.bits = state->bits;
ar.lcode = state->lencode;
ar.dcode = state->distcode;
ar.lmask = (1U << state->lenbits) - 1;
ar.dmask = (1U << state->distbits) - 1;
/* decode literals and length/distances until end-of-block or not enough
input data or output space */
/* align in on 2 byte boundary */
if (((unsigned long)(void *)ar.in & 0x1) != 0) {
ar.hold += (unsigned long)*ar.in++ << ar.bits;
ar.bits += 8;
}
#if defined( __GNUC__ ) || defined( __ICC )
__asm__ __volatile__ (
" leal %0, %%eax\n"
" pushf\n"
" pushl %%ebp\n"
" movl %%esp, (%%eax)\n"
" movl %%eax, %%esp\n"
" movl 4(%%esp), %%esi\n" /* esi = in */
" movl 12(%%esp), %%edi\n" /* edi = out */
" movl 36(%%esp), %%edx\n" /* edx = hold */
" movl 40(%%esp), %%ebx\n" /* ebx = bits */
" movl 44(%%esp), %%ebp\n" /* ebp = lcode */
" cld\n"
" jmp .L_do_loop\n"
".L_while_test:\n"
" cmpl %%edi, 20(%%esp)\n"
" jbe .L_break_loop\n"
" cmpl %%esi, 8(%%esp)\n"
" jbe .L_break_loop\n"
".L_do_loop:\n"
" cmpb $15, %%bl\n"
" ja .L_get_length_code\n" /* if (15 < bits) */
" xorl %%eax, %%eax\n"
" lodsw\n" /* al = *(ushort *)in++ */
" movb %%bl, %%cl\n" /* cl = bits, needs it for shifting */
" addb $16, %%bl\n" /* bits += 16 */
" shll %%cl, %%eax\n"
" orl %%eax, %%edx\n" /* hold |= *((ushort *)in)++ << bits */
".L_get_length_code:\n"
" movl 52(%%esp), %%eax\n" /* eax = lmask */
" andl %%edx, %%eax\n" /* eax &= hold */
" movl (%%ebp,%%eax,4), %%eax\n" /* eax = lcode[hold & lmask] */
".L_dolen:\n"
" movb %%ah, %%cl\n" /* cl = this.bits */
" subb %%ah, %%bl\n" /* bits -= this.bits */
" shrl %%cl, %%edx\n" /* hold >>= this.bits */
" testb %%al, %%al\n"
" jnz .L_test_for_length_base\n" /* if (op != 0) 45.7% */
" shrl $16, %%eax\n" /* output this.val char */
" stosb\n"
" jmp .L_while_test\n"
".L_test_for_length_base:\n"
" movl %%eax, %%ecx\n" /* len = this */
" shrl $16, %%ecx\n" /* len = this.val */
" movl %%ecx, 60(%%esp)\n" /* len = this */
" movb %%al, %%cl\n"
" testb $16, %%al\n"
" jz .L_test_for_second_level_length\n" /* if ((op & 16) == 0) 8% */
" andb $15, %%cl\n" /* op &= 15 */
" jz .L_decode_distance\n" /* if (!op) */
" cmpb %%cl, %%bl\n"
" jae .L_add_bits_to_len\n" /* if (op <= bits) */
" movb %%cl, %%ch\n" /* stash op in ch, freeing cl */
" xorl %%eax, %%eax\n"
" lodsw\n" /* al = *(ushort *)in++ */
" movb %%bl, %%cl\n" /* cl = bits, needs it for shifting */
" addb $16, %%bl\n" /* bits += 16 */
" shll %%cl, %%eax\n"
" orl %%eax, %%edx\n" /* hold |= *((ushort *)in)++ << bits */
" movb %%ch, %%cl\n" /* move op back to ecx */
".L_add_bits_to_len:\n"
" movl $1, %%eax\n"
" shll %%cl, %%eax\n"
" decl %%eax\n"
" subb %%cl, %%bl\n"
" andl %%edx, %%eax\n" /* eax &= hold */
" shrl %%cl, %%edx\n"
" addl %%eax, 60(%%esp)\n" /* len += hold & mask[op] */
".L_decode_distance:\n"
" cmpb $15, %%bl\n"
" ja .L_get_distance_code\n" /* if (15 < bits) */
" xorl %%eax, %%eax\n"
" lodsw\n" /* al = *(ushort *)in++ */
" movb %%bl, %%cl\n" /* cl = bits, needs it for shifting */
" addb $16, %%bl\n" /* bits += 16 */
" shll %%cl, %%eax\n"
" orl %%eax, %%edx\n" /* hold |= *((ushort *)in)++ << bits */
".L_get_distance_code:\n"
" movl 56(%%esp), %%eax\n" /* eax = dmask */
" movl 48(%%esp), %%ecx\n" /* ecx = dcode */
" andl %%edx, %%eax\n" /* eax &= hold */
" movl (%%ecx,%%eax,4), %%eax\n"/* eax = dcode[hold & dmask] */
".L_dodist:\n"
" movl %%eax, %%ebp\n" /* dist = this */
" shrl $16, %%ebp\n" /* dist = this.val */
" movb %%ah, %%cl\n"
" subb %%ah, %%bl\n" /* bits -= this.bits */
" shrl %%cl, %%edx\n" /* hold >>= this.bits */
" movb %%al, %%cl\n" /* cl = this.op */
" testb $16, %%al\n" /* if ((op & 16) == 0) */
" jz .L_test_for_second_level_dist\n"
" andb $15, %%cl\n" /* op &= 15 */
" jz .L_check_dist_one\n"
" cmpb %%cl, %%bl\n"
" jae .L_add_bits_to_dist\n" /* if (op <= bits) 97.6% */
" movb %%cl, %%ch\n" /* stash op in ch, freeing cl */
" xorl %%eax, %%eax\n"
" lodsw\n" /* al = *(ushort *)in++ */
" movb %%bl, %%cl\n" /* cl = bits, needs it for shifting */
" addb $16, %%bl\n" /* bits += 16 */
" shll %%cl, %%eax\n"
" orl %%eax, %%edx\n" /* hold |= *((ushort *)in)++ << bits */
" movb %%ch, %%cl\n" /* move op back to ecx */
".L_add_bits_to_dist:\n"
" movl $1, %%eax\n"
" shll %%cl, %%eax\n"
" decl %%eax\n" /* (1 << op) - 1 */
" subb %%cl, %%bl\n"
" andl %%edx, %%eax\n" /* eax &= hold */
" shrl %%cl, %%edx\n"
" addl %%eax, %%ebp\n" /* dist += hold & ((1 << op) - 1) */
".L_check_window:\n"
" movl %%esi, 4(%%esp)\n" /* save in so from can use it's reg */
" movl %%edi, %%eax\n"
" subl 16(%%esp), %%eax\n" /* nbytes = out - beg */
" cmpl %%ebp, %%eax\n"
" jb .L_clip_window\n" /* if (dist > nbytes) 4.2% */
" movl 60(%%esp), %%ecx\n"
" movl %%edi, %%esi\n"
" subl %%ebp, %%esi\n" /* from = out - dist */
" subl $3, %%ecx\n" /* copy from to out */
" movb (%%esi), %%al\n"
" movb %%al, (%%edi)\n"
" movb 1(%%esi), %%al\n"
" movb 2(%%esi), %%ah\n"
" addl $3, %%esi\n"
" movb %%al, 1(%%edi)\n"
" movb %%ah, 2(%%edi)\n"
" addl $3, %%edi\n"
" rep movsb\n"
" movl 4(%%esp), %%esi\n" /* move in back to %esi, toss from */
" movl 44(%%esp), %%ebp\n" /* ebp = lcode */
" jmp .L_while_test\n"
".L_check_dist_one:\n"
" cmpl $1, %%ebp\n" /* if dist 1, is a memset */
" jne .L_check_window\n"
" cmpl %%edi, 16(%%esp)\n"
" je .L_check_window\n"
" decl %%edi\n"
" movl 60(%%esp), %%ecx\n"
" movb (%%edi), %%al\n"
" subl $3, %%ecx\n"
" movb %%al, 1(%%edi)\n" /* memset out with from[-1] */
" movb %%al, 2(%%edi)\n"
" movb %%al, 3(%%edi)\n"
" addl $4, %%edi\n"
" rep stosb\n"
" movl 44(%%esp), %%ebp\n" /* ebp = lcode */
" jmp .L_while_test\n"
".L_test_for_second_level_length:\n"
" testb $64, %%al\n"
" jnz .L_test_for_end_of_block\n" /* if ((op & 64) != 0) */
" movl $1, %%eax\n"
" shll %%cl, %%eax\n"
" decl %%eax\n"
" andl %%edx, %%eax\n" /* eax &= hold */
" addl 60(%%esp), %%eax\n" /* eax += this.val */
" movl (%%ebp,%%eax,4), %%eax\n" /* eax = lcode[val+(hold&mask[op])]*/
" jmp .L_dolen\n"
".L_test_for_second_level_dist:\n"
" testb $64, %%al\n"
" jnz .L_invalid_distance_code\n" /* if ((op & 64) != 0) */
" movl $1, %%eax\n"
" shll %%cl, %%eax\n"
" decl %%eax\n"
" andl %%edx, %%eax\n" /* eax &= hold */
" addl %%ebp, %%eax\n" /* eax += this.val */
" movl 48(%%esp), %%ecx\n" /* ecx = dcode */
" movl (%%ecx,%%eax,4), %%eax\n" /* eax = dcode[val+(hold&mask[op])]*/
" jmp .L_dodist\n"
".L_clip_window:\n"
" movl %%eax, %%ecx\n"
" movl 24(%%esp), %%eax\n" /* prepare for dist compare */
" negl %%ecx\n" /* nbytes = -nbytes */
" movl 32(%%esp), %%esi\n" /* from = window */
" cmpl %%ebp, %%eax\n"
" jb .L_invalid_distance_too_far\n" /* if (dist > wsize) */
" addl %%ebp, %%ecx\n" /* nbytes = dist - nbytes */
" cmpl $0, 28(%%esp)\n"
" jne .L_wrap_around_window\n" /* if (write != 0) */
" subl %%ecx, %%eax\n"
" addl %%eax, %%esi\n" /* from += wsize - nbytes */
" movl 60(%%esp), %%eax\n"
" cmpl %%ecx, %%eax\n"
" jbe .L_do_copy1\n" /* if (nbytes >= len) */
" subl %%ecx, %%eax\n" /* len -= nbytes */
" rep movsb\n"
" movl %%edi, %%esi\n"
" subl %%ebp, %%esi\n" /* from = out - dist */
" jmp .L_do_copy1\n"
" cmpl %%ecx, %%eax\n"
" jbe .L_do_copy1\n" /* if (nbytes >= len) */
" subl %%ecx, %%eax\n" /* len -= nbytes */
" rep movsb\n"
" movl %%edi, %%esi\n"
" subl %%ebp, %%esi\n" /* from = out - dist */
" jmp .L_do_copy1\n"
".L_wrap_around_window:\n"
" movl 28(%%esp), %%eax\n"
" cmpl %%eax, %%ecx\n"
" jbe .L_contiguous_in_window\n" /* if (write >= nbytes) */
" addl 24(%%esp), %%esi\n"
" addl %%eax, %%esi\n"
" subl %%ecx, %%esi\n" /* from += wsize + write - nbytes */
" subl %%eax, %%ecx\n" /* nbytes -= write */
" movl 60(%%esp), %%eax\n"
" cmpl %%ecx, %%eax\n"
" jbe .L_do_copy1\n" /* if (nbytes >= len) */
" subl %%ecx, %%eax\n" /* len -= nbytes */
" rep movsb\n"
" movl 32(%%esp), %%esi\n" /* from = window */
" movl 28(%%esp), %%ecx\n" /* nbytes = write */
" cmpl %%ecx, %%eax\n"
" jbe .L_do_copy1\n" /* if (nbytes >= len) */
" subl %%ecx, %%eax\n" /* len -= nbytes */
" rep movsb\n"
" movl %%edi, %%esi\n"
" subl %%ebp, %%esi\n" /* from = out - dist */
" jmp .L_do_copy1\n"
".L_contiguous_in_window:\n"
" addl %%eax, %%esi\n"
" subl %%ecx, %%esi\n" /* from += write - nbytes */
" movl 60(%%esp), %%eax\n"
" cmpl %%ecx, %%eax\n"
" jbe .L_do_copy1\n" /* if (nbytes >= len) */
" subl %%ecx, %%eax\n" /* len -= nbytes */
" rep movsb\n"
" movl %%edi, %%esi\n"
" subl %%ebp, %%esi\n" /* from = out - dist */
".L_do_copy1:\n"
" movl %%eax, %%ecx\n"
" rep movsb\n"
" movl 4(%%esp), %%esi\n" /* move in back to %esi, toss from */
" movl 44(%%esp), %%ebp\n" /* ebp = lcode */
" jmp .L_while_test\n"
".L_test_for_end_of_block:\n"
" testb $32, %%al\n"
" jz .L_invalid_literal_length_code\n"
" movl $1, 68(%%esp)\n"
" jmp .L_break_loop_with_status\n"
".L_invalid_literal_length_code:\n"
" movl $2, 68(%%esp)\n"
" jmp .L_break_loop_with_status\n"
".L_invalid_distance_code:\n"
" movl $3, 68(%%esp)\n"
" jmp .L_break_loop_with_status\n"
".L_invalid_distance_too_far:\n"
" movl 4(%%esp), %%esi\n"
" movl $4, 68(%%esp)\n"
" jmp .L_break_loop_with_status\n"
".L_break_loop:\n"
" movl $0, 68(%%esp)\n"
".L_break_loop_with_status:\n"
/* put in, out, bits, and hold back into ar and pop esp */
" movl %%esi, 4(%%esp)\n"
" movl %%edi, 12(%%esp)\n"
" movl %%ebx, 40(%%esp)\n"
" movl %%edx, 36(%%esp)\n"
" movl (%%esp), %%esp\n"
" popl %%ebp\n"
" popf\n"
:
: "m" (ar)
: "memory", "%eax", "%ebx", "%ecx", "%edx", "%esi", "%edi"
);
#elif defined( _MSC_VER )
__asm {
lea eax, ar
pushfd
push ebp
mov [eax], esp
mov esp, eax
mov esi, [esp+4] /* esi = in */
mov edi, [esp+12] /* edi = out */
mov edx, [esp+36] /* edx = hold */
mov ebx, [esp+40] /* ebx = bits */
mov ebp, [esp+44] /* ebp = lcode */
cld
jmp L_do_loop
L_while_test:
cmp [esp+20], edi
jbe L_break_loop
cmp [esp+8], esi
jbe L_break_loop
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 */
and eax, edx /* eax &= hold */
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 */
shr ecx, 16 /* len = this.val */
mov [esp+60], ecx /* len = this */
mov cl, al
test al, 16
jz L_test_for_second_level_length /* if ((op & 16) == 0) 8% */
and cl, 15 /* op &= 15 */
jz L_decode_distance /* if (!op) */
cmp bl, cl
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++ */
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_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
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_distance_code:
mov eax, [esp+56] /* eax = dmask */
mov ecx, [esp+48] /* ecx = dcode */
and eax, edx /* eax &= hold */
mov eax, [ecx+eax*4]/* eax = dcode[hold & dmask] */
L_dodist:
mov ebp, eax /* dist = this */
shr ebp, 16 /* dist = this.val */
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;
}
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