blob: aa138354330fa8d6a808bc7daeaa84f5628c7626 [file] [log] [blame]
/* lzo1x_d.ash -- assembler implementation of the LZO1X decompression algorithm
This file is part of the LZO real-time data compression library.
Copyright (C) 2008 Markus Franz Xaver Johannes Oberhumer
Copyright (C) 2007 Markus Franz Xaver Johannes Oberhumer
Copyright (C) 2006 Markus Franz Xaver Johannes Oberhumer
Copyright (C) 2005 Markus Franz Xaver Johannes Oberhumer
Copyright (C) 2004 Markus Franz Xaver Johannes Oberhumer
Copyright (C) 2003 Markus Franz Xaver Johannes Oberhumer
Copyright (C) 2002 Markus Franz Xaver Johannes Oberhumer
Copyright (C) 2001 Markus Franz Xaver Johannes Oberhumer
Copyright (C) 2000 Markus Franz Xaver Johannes Oberhumer
Copyright (C) 1999 Markus Franz Xaver Johannes Oberhumer
Copyright (C) 1998 Markus Franz Xaver Johannes Oberhumer
Copyright (C) 1997 Markus Franz Xaver Johannes Oberhumer
Copyright (C) 1996 Markus Franz Xaver Johannes Oberhumer
All Rights Reserved.
The LZO library is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of
the License, or (at your option) any later version.
The LZO library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with the LZO library; see the file COPYING.
If not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
Markus F.X.J. Oberhumer
<markus@oberhumer.com>
http://www.oberhumer.com/opensource/lzo/
*/
#if !defined(LZO1X) && !defined(LZO1Y)
# define LZO1X
#endif
#if defined(LZO_FAST)
# define NN 3
#else
# define NN 0
#endif
/***********************************************************************
// init
************************************************************************/
xorl %eax,%eax
xorl %ebx,%ebx /* high bits 9-32 stay 0 */
lodsb
cmpb $17,%al
jbe .L01
subb $17-NN,%al
#if defined(LZO_FAST)
jmp .LFLR
#else
cmpb $4,%al
jae .LFLR
#if 1
TEST_OP((%edi,%eax),%edx)
TEST_IP((%esi,%eax),%edx)
movl %eax,%ecx
jmp .LFLR2
#else
jmp .LFLR3
#endif
#endif
/***********************************************************************
// literal run
************************************************************************/
0: addl N_255,%eax
TEST_IP(18(%esi,%eax),%edx) /* minimum */
1: movb (%esi),%bl
incl %esi
orb %bl,%bl
jz 0b
leal 18+NN(%eax,%ebx),%eax
jmp 3f
ALIGN3
.L00:
#ifdef LZO_DEBUG
andl $0xffffff00,%eax ; jnz .L_assert_fail
andl $0xffffff00,%ebx ; jnz .L_assert_fail
xorl %eax,%eax ; xorl %ebx,%ebx
xorl %ecx,%ecx ; xorl %edx,%edx
#endif
TEST_IP_R(%esi)
LODSB
.L01:
cmpb $16,%al
jae .LMATCH
/* a literal run */
orb %al,%al
jz 1b
addl $3+NN,%eax
3:
.LFLR:
TEST_OP(-NN(%edi,%eax),%edx)
TEST_IP(-NN(%esi,%eax),%edx)
#if defined(LZO_FAST)
movl %eax,%ecx
NOTL_3(%eax)
shrl $2,%ecx
andl N_3,%eax
COPYL(%esi,%edi,%edx)
subl %eax,%esi
subl %eax,%edi
#else
movl %eax,%ecx
shrl $2,%eax
andl N_3,%ecx
COPYL_C(%esi,%edi,%edx,%eax)
.LFLR2:
rep
movsb
#endif
#ifdef LZO_DEBUG
andl $0xffffff00,%eax ; jnz .L_assert_fail
andl $0xffffff00,%ebx ; jnz .L_assert_fail
xorl %eax,%eax ; xorl %ebx,%ebx
xorl %ecx,%ecx ; xorl %edx,%edx
#endif
LODSB
cmpb $16,%al
jae .LMATCH
/***********************************************************************
// R1
************************************************************************/
TEST_OP(3(%edi),%edx)
shrl $2,%eax
movb (%esi),%bl
#if defined(LZO1X)
leal -0x801(%edi),%edx
#elif defined(LZO1Y)
leal -0x401(%edi),%edx
#endif
leal (%eax,%ebx,4),%eax
incl %esi
subl %eax,%edx
TEST_LOOKBEHIND(%edx)
#if defined(LZO_FAST)
movl (%edx),%ecx
movl %ecx,(%edi)
#else
movb (%edx),%al
movb %al,(%edi)
movb 1(%edx),%al
movb %al,1(%edi)
movb 2(%edx),%al
movb %al,2(%edi)
#endif
addl N_3,%edi
jmp .LMDONE
/***********************************************************************
// M2
************************************************************************/
ALIGN3
.LMATCH:
cmpb $64,%al
jb .LM3MATCH
/* a M2 match */
movl %eax,%ecx
shrl $2,%eax
leal -1(%edi),%edx
#if defined(LZO1X)
andl $7,%eax
movb (%esi),%bl
shrl $5,%ecx
leal (%eax,%ebx,8),%eax
#elif defined(LZO1Y)
andl N_3,%eax
movb (%esi),%bl
shrl $4,%ecx
leal (%eax,%ebx,4),%eax
#endif
incl %esi
subl %eax,%edx
#if defined(LZO_FAST)
#if defined(LZO1X)
addl $1+3,%ecx
#elif defined(LZO1Y)
addl $2,%ecx
#endif
#else
#if defined(LZO1X)
incl %ecx
#elif defined(LZO1Y)
decl %ecx
#endif
#endif
cmpl N_3,%eax
jae .LCOPYLONG
jmp .LCOPYBYTE
/***********************************************************************
// M3
************************************************************************/
0: addl N_255,%eax
TEST_IP(3(%esi),%edx) /* minimum */
1: movb (%esi),%bl
incl %esi
orb %bl,%bl
jz 0b
leal 33+NN(%eax,%ebx),%ecx
xorl %eax,%eax
jmp 3f
ALIGN3
.LM3MATCH:
cmpb $32,%al
jb .LM4MATCH
/* a M3 match */
andl $31,%eax
jz 1b
lea 2+NN(%eax),%ecx
3:
#ifdef LZO_DEBUG
andl $0xffff0000,%eax ; jnz .L_assert_fail
#endif
movw (%esi),%ax
leal -1(%edi),%edx
shrl $2,%eax
addl $2,%esi
subl %eax,%edx
cmpl N_3,%eax
jb .LCOPYBYTE
/***********************************************************************
// copy match
************************************************************************/
ALIGN1
.LCOPYLONG: /* copy match using longwords */
TEST_LOOKBEHIND(%edx)
#if defined(LZO_FAST)
leal -3(%edi,%ecx),%eax
shrl $2,%ecx
TEST_OP_R(%eax)
COPYL(%edx,%edi,%ebx)
movl %eax,%edi
xorl %ebx,%ebx
#else
TEST_OP((%edi,%ecx),%eax)
movl %ecx,%ebx
shrl $2,%ebx
jz 2f
COPYL_C(%edx,%edi,%eax,%ebx)
andl N_3,%ecx
jz 1f
2: COPYB_C(%edx,%edi,%al,%ecx)
1:
#endif
.LMDONE:
movb -2(%esi),%al
andl N_3,%eax
jz .L00
.LFLR3:
TEST_OP((%edi,%eax),%edx)
TEST_IP((%esi,%eax),%edx)
#if defined(LZO_FAST)
movl (%esi),%edx
addl %eax,%esi
movl %edx,(%edi)
addl %eax,%edi
#else
COPYB_C(%esi,%edi,%cl,%eax)
#endif
#ifdef LZO_DEBUG
andl $0xffffff00,%eax ; jnz .L_assert_fail
andl $0xffffff00,%ebx ; jnz .L_assert_fail
xorl %eax,%eax ; xorl %ebx,%ebx
xorl %ecx,%ecx ; xorl %edx,%edx
#endif
LODSB
jmp .LMATCH
ALIGN3
.LCOPYBYTE: /* copy match using bytes */
TEST_LOOKBEHIND(%edx)
TEST_OP(-NN(%edi,%ecx),%eax)
xchgl %edx,%esi
#if defined(LZO_FAST)
subl N_3,%ecx
#endif
rep
movsb
movl %edx,%esi
jmp .LMDONE
/***********************************************************************
// M4
************************************************************************/
0: addl N_255,%ecx
TEST_IP(3(%esi),%edx) /* minimum */
1: movb (%esi),%bl
incl %esi
orb %bl,%bl
jz 0b
leal 9+NN(%ebx,%ecx),%ecx
jmp 3f
ALIGN3
.LM4MATCH:
cmpb $16,%al
jb .LM1MATCH
/* a M4 match */
movl %eax,%ecx
andl $8,%eax
shll $13,%eax /* save in bit 16 */
andl $7,%ecx
jz 1b
addl $2+NN,%ecx
3:
#ifdef LZO_DEBUG
movl %eax,%edx ; andl $0xfffe0000,%edx ; jnz .L_assert_fail
#endif
movw (%esi),%ax
addl $2,%esi
leal -0x4000(%edi),%edx
shrl $2,%eax
jz .LEOF
subl %eax,%edx
jmp .LCOPYLONG
/***********************************************************************
// M1
************************************************************************/
ALIGN3
.LM1MATCH:
/* a M1 match */
TEST_OP(2(%edi),%edx)
shrl $2,%eax
movb (%esi),%bl
leal -1(%edi),%edx
leal (%eax,%ebx,4),%eax
incl %esi
subl %eax,%edx
TEST_LOOKBEHIND(%edx)
movb (%edx),%al /* we must use this because edx can be edi-1 */
movb %al,(%edi)
movb 1(%edx),%bl
movb %bl,1(%edi)
addl $2,%edi
jmp .LMDONE
/***********************************************************************
//
************************************************************************/
.LEOF:
/**** xorl %eax,%eax eax=0 from above */
cmpl $3+NN,%ecx /* ecx must be 3/6 */
setnz %al
/*
vi:ts=4
*/