/*

decode_i586_dither: asm synth with dither noise

copyright ?-2007 by the mpg123 project - free software under the terms of the LGPL 2.1

see COPYING and AUTHORS files in distribution or http://mpg123.org

initially written by Stefan Bieschewski as decode_i586.s without dither

This version uses "circular" 64k dither noise.

(Patch by Adrian <adrian.bacon@xs4all.nl>)

Thomas learned something about assembler and the stack while making this one thread safe (removing static data).

*/

#include "mangle.h"

#if !defined(__APPLE__) && !defined(__EMX__)

.section .rodata

#else

.data

#endif

ALIGN8

.LC0:

.long 0x0,0x40dfffc0

ALIGN8

.LC1:

.long 0x0,0xc0e00000

ALIGN8

.text

/* int synth_1to1_i586_asm_dither(real *bandPtr, int channel, unsigned char *out, unsigned char *buffs, int bo_and_ditherindex[2], real *decwin, real* dithernoise); */

.globl ASM_NAME(synth_1to1_i586_asm_dither)

ASM_NAME(synth_1to1_i586_asm_dither):

subl $16,%esp

pushl %ebp

pushl %edi

pushl %esi

pushl %ebx

/* stack: 0(%esp)=%ebx 4=esi 8=edi 12=ebp 16,20,24,28=local 32=back 36=bandptr 40=channel 44=out 48=buffs 52=bo 56=decwin 60=dithernoise */

#define BANDPTR 36(%esp)

#define CHANNEL 40(%esp)

#define OUT 44(%esp)

#define BUFFS 48(%esp)

#define BO 52(%esp)

#define DECWIN 56(%esp)

#define DITHERNOISE 60(%esp)

/*#define DITHERNOISE $(ASM_NAME(dithernoise))*/

#define LOC0 16(%esp)

#define LOC1 20(%esp)

#define LOC2 24(%esp)

#define DITHERINDEX 28(%esp)

/* During application of the dithering, we need the shifted locations because there's an additional value on the stack. */

#define DITHERNOISE2 64(%esp)

#define DITHERINDEX2 32(%esp)

movl BANDPTR,%eax

movl OUT,%esi

movl BO, %ebx

movl (%ebx),%ebp /* get bo value */

movl 4(%ebx),%edi; /* get the ditherindex behind bo */

movl %edi,DITHERINDEX

xorl %edi,%edi

cmpl %edi,CHANNEL

jne .L48

decl %ebp

andl $15,%ebp

movl %ebp,(%ebx) /* save bo back */

movl BUFFS,%ecx

jmp .L49

.L48:

/* In stereo mode , "rewind" dither pointer 32 samples , so 2nd channel */

/* has same dither values. Tested OK for mono and stereo MP2 and MP3 */

subl $128,DITHERINDEX /* better move to %edi for the two calculations? */

andl $0x0003fffc,DITHERINDEX

addl $2,%esi

movl BUFFS,%ecx

addl $2176,%ecx

.L49:

/* now the call of dct64 is prepared, stuff pushed to the stack, but soon after it's removed again */

testl $1,%ebp

je .L50

movl %ecx,%ebx

movl %ebp,LOC0

pushl %eax

movl LOC1,%edx

leal (%ebx,%edx,4),%eax

pushl %eax

movl LOC2,%eax

incl %eax

andl $15,%eax

leal 1088(,%eax,4),%eax

addl %ebx,%eax

jmp .L74

.L50:

leal 1088(%ecx),%ebx

leal 1(%ebp),%edx

movl %edx,LOC0

pushl %eax

leal 1092(%ecx,%ebp,4),%eax

pushl %eax

leal (%ecx,%ebp,4),%eax

.L74:

pushl %eax

call FUNC(dct64_i386)

addl $12,%esp

/* Now removed the parameters.

stack: 0(%esp)=%ebx 4=esi 8=edi 12=ebp 16,20,24,28=local 32=back 36=bandptr 40=channel 44=out 48=buffs 52=bo 56=decwin 60=dithernoise */

movl LOC0,%edx

leal 0(,%edx,4),%edx

/* movl ASM_VALUE(decwin)+64,%eax */

movl DECWIN,%eax

addl $64,%eax

movl %eax,%ecx

subl %edx,%ecx

movl $16,%ebp

.L55:

flds (%ecx)

fmuls (%ebx)

flds 4(%ecx)

fmuls 4(%ebx)

fxch %st(1)

flds 8(%ecx)

fmuls 8(%ebx)

fxch %st(2)

fsubrp %st,%st(1)

flds 12(%ecx)

fmuls 12(%ebx)

fxch %st(2)

faddp %st,%st(1)

flds 16(%ecx)

fmuls 16(%ebx)

fxch %st(2)

fsubrp %st,%st(1)

flds 20(%ecx)

fmuls 20(%ebx)

fxch %st(2)

faddp %st,%st(1)

flds 24(%ecx)

fmuls 24(%ebx)

fxch %st(2)

fsubrp %st,%st(1)

flds 28(%ecx)

fmuls 28(%ebx)

fxch %st(2)

faddp %st,%st(1)

flds 32(%ecx)

fmuls 32(%ebx)

fxch %st(2)

fsubrp %st,%st(1)

flds 36(%ecx)

fmuls 36(%ebx)

fxch %st(2)

faddp %st,%st(1)

flds 40(%ecx)

fmuls 40(%ebx)

fxch %st(2)

fsubrp %st,%st(1)

flds 44(%ecx)

fmuls 44(%ebx)

fxch %st(2)

faddp %st,%st(1)

flds 48(%ecx)

fmuls 48(%ebx)

fxch %st(2)

fsubrp %st,%st(1)

flds 52(%ecx)

fmuls 52(%ebx)

fxch %st(2)

faddp %st,%st(1)

flds 56(%ecx)

fmuls 56(%ebx)

fxch %st(2)

fsubrp %st,%st(1)

flds 60(%ecx)

fmuls 60(%ebx)

fxch %st(2)

subl $4,%esp

faddp %st,%st(1)

fxch %st(1)

fsubrp %st,%st(1)

addl $4,DITHERINDEX2

andl $0x0003fffc,DITHERINDEX2

movl DITHERNOISE2,%edi

addl DITHERINDEX2,%edi

fadds (%edi)

/* fistpl and popl as a unit keep the stack unchanged */

fistpl (%esp)

popl %eax

cmpl $32767,%eax

jg 1f

cmpl $-32768,%eax

jl 2f

movw %ax,(%esi)

jmp 4f

1: movw $32767,(%esi)

jmp 3f

2: movw $-32768,(%esi)

3:

/* incl %edi */

4:

.L54:

addl $64,%ebx

subl $-128,%ecx

addl $4,%esi

decl %ebp

jnz .L55

flds (%ecx)

fmuls (%ebx)

flds 8(%ecx)

fmuls 8(%ebx)

flds 16(%ecx)

fmuls 16(%ebx)

fxch %st(2)

faddp %st,%st(1)

flds 24(%ecx)

fmuls 24(%ebx)

fxch %st(2)

faddp %st,%st(1)

flds 32(%ecx)

fmuls 32(%ebx)

fxch %st(2)

faddp %st,%st(1)

flds 40(%ecx)

fmuls 40(%ebx)

fxch %st(2)

faddp %st,%st(1)

flds 48(%ecx)

fmuls 48(%ebx)

fxch %st(2)

faddp %st,%st(1)

flds 56(%ecx)

fmuls 56(%ebx)

fxch %st(2)

subl $4,%esp

faddp %st,%st(1)

fxch %st(1)

faddp %st,%st(1)

addl $4,DITHERINDEX2

andl $0x0003fffc,DITHERINDEX2

movl DITHERNOISE2,%edi

addl DITHERINDEX2,%edi

fadds (%edi)

/* fistpl and popl as a unit keep the stack unchanged */

fistpl (%esp)

popl %eax

cmpl $32767,%eax

jg 1f

cmpl $-32768,%eax

jl 2f

movw %ax,(%esi)

jmp 4f

1: movw $32767,(%esi)

jmp 3f

2: movw $-32768,(%esi)

3:

/* incl %edi */

4:

.L62:

addl $-64,%ebx

addl $4,%esi

movl LOC0,%edx

leal -128(%ecx,%edx,8),%ecx

movl $15,%ebp

.L68:

flds -4(%ecx)

fchs

fmuls (%ebx)

flds -8(%ecx)

fmuls 4(%ebx)

fxch %st(1)

flds -12(%ecx)

fmuls 8(%ebx)

fxch %st(2)

fsubrp %st,%st(1)

flds -16(%ecx)

fmuls 12(%ebx)

fxch %st(2)

fsubrp %st,%st(1)

flds -20(%ecx)

fmuls 16(%ebx)

fxch %st(2)

fsubrp %st,%st(1)

flds -24(%ecx)

fmuls 20(%ebx)

fxch %st(2)

fsubrp %st,%st(1)

flds -28(%ecx)

fmuls 24(%ebx)

fxch %st(2)

fsubrp %st,%st(1)

flds -32(%ecx)

fmuls 28(%ebx)

fxch %st(2)

fsubrp %st,%st(1)

flds -36(%ecx)

fmuls 32(%ebx)

fxch %st(2)

fsubrp %st,%st(1)

flds -40(%ecx)

fmuls 36(%ebx)

fxch %st(2)

fsubrp %st,%st(1)

flds -44(%ecx)

fmuls 40(%ebx)

fxch %st(2)

fsubrp %st,%st(1)

flds -48(%ecx)

fmuls 44(%ebx)

fxch %st(2)

fsubrp %st,%st(1)

flds -52(%ecx)

fmuls 48(%ebx)

fxch %st(2)

fsubrp %st,%st(1)

flds -56(%ecx)

fmuls 52(%ebx)

fxch %st(2)

fsubrp %st,%st(1)

flds -60(%ecx)

fmuls 56(%ebx)

fxch %st(2)

fsubrp %st,%st(1)

flds (%ecx)

fmuls 60(%ebx)

fxch %st(2)

subl $4,%esp

fsubrp %st,%st(1)

fxch %st(1)

fsubrp %st,%st(1)

addl $4,DITHERINDEX2

andl $0x0003fffc,DITHERINDEX2

movl DITHERNOISE2,%edi

addl DITHERINDEX2,%edi

fadds (%edi)

/* fistpl and popl as a unit keep the stack unchanged */

fistpl (%esp)

popl %eax

cmpl $32767,%eax

jg 1f

cmpl $-32768,%eax

jl 2f

movw %ax,(%esi)

jmp 4f

1: movw $32767,(%esi)

jmp 3f

2: movw $-32768,(%esi)

3:

/* incl %edi */

4:

.L67:

addl $-64,%ebx

addl $-128,%ecx

addl $4,%esi

decl %ebp

jnz .L68

/* return ipv edi 0 in eax */

movl $0,%eax

/* save ditherindex */

movl BO,%ebx

movl DITHERINDEX,%esi

movl %esi,4(%ebx);

/* stack: 0=ebx 4=esi 8=edi 12=ebp 16,20,24,28=local 32=back 36=bandptr 40=channel 44=out 48=buffs 52=bo */

popl %ebx

popl %esi

popl %edi

popl %ebp

addl $16,%esp

/* The stack must be now: 0=back 4=bandptr 8=channel 12=out 16=buffs 20=bo */

ret

#if defined(PIC) && defined(__APPLE__)

.section __IMPORT,__jump_table,symbol_stubs,self_modifying_code+pure_instructions,5

L_dct64_i386:

.indirect_symbol ASM_NAME(dct64_i386)

hlt ; hlt ; hlt ; hlt ; hlt

#endif

NONEXEC_STACK