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- /*
- Copyright (C) 1996-1997 Id Software, Inc.
-
- This program 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.
-
- This program 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 this program; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
-
- */
- //
- // snd_mixa.s
- // x86 assembly-language sound code
- //
-
- #include "asm_i386.h"
- #include "quakeasm.h"
-
- #if id386
-
- .text
-
- //----------------------------------------------------------------------
- // 8-bit sound-mixing code
- //----------------------------------------------------------------------
-
- #define ch 4+16
- #define sc 8+16
- #define count 12+16
-
- .globl C(SND_PaintChannelFrom8)
- C(SND_PaintChannelFrom8):
- pushl %esi // preserve register variables
- pushl %edi
- pushl %ebx
- pushl %ebp
-
- // int data;
- // short *lscale, *rscale;
- // unsigned char *sfx;
- // int i;
-
- movl ch(%esp),%ebx
- movl sc(%esp),%esi
-
- // if (ch->leftvol > 255)
- // ch->leftvol = 255;
- // if (ch->rightvol > 255)
- // ch->rightvol = 255;
- movl ch_leftvol(%ebx),%eax
- movl ch_rightvol(%ebx),%edx
- cmpl $255,%eax
- jna LLeftSet
- movl $255,%eax
- LLeftSet:
- cmpl $255,%edx
- jna LRightSet
- movl $255,%edx
- LRightSet:
-
- // lscale = snd_scaletable[ch->leftvol >> 3];
- // rscale = snd_scaletable[ch->rightvol >> 3];
- // sfx = (signed char *)sc->data + ch->pos;
- // ch->pos += count;
- andl $0xF8,%eax
- addl $(sfxc_data),%esi
- andl $0xF8,%edx
- movl ch_pos(%ebx),%edi
- movl count(%esp),%ecx
- addl %edi,%esi
- shll $7,%eax
- addl %ecx,%edi
- shll $7,%edx
- movl %edi,ch_pos(%ebx)
- addl $(C(snd_scaletable)),%eax
- addl $(C(snd_scaletable)),%edx
- subl %ebx,%ebx
- movb -1(%esi,%ecx,1),%bl
-
- testl $1,%ecx
- jz LMix8Loop
-
- movl (%eax,%ebx,4),%edi
- movl (%edx,%ebx,4),%ebp
- addl C(paintbuffer)+psp_left-psp_size(,%ecx,psp_size),%edi
- addl C(paintbuffer)+psp_right-psp_size(,%ecx,psp_size),%ebp
- movl %edi,C(paintbuffer)+psp_left-psp_size(,%ecx,psp_size)
- movl %ebp,C(paintbuffer)+psp_right-psp_size(,%ecx,psp_size)
- movb -2(%esi,%ecx,1),%bl
-
- decl %ecx
- jz LDone
-
- // for (i=0 ; i<count ; i++)
- // {
- LMix8Loop:
-
- // data = sfx[i];
- // paintbuffer[i].left += lscale[data];
- // paintbuffer[i].right += rscale[data];
- movl (%eax,%ebx,4),%edi
- movl (%edx,%ebx,4),%ebp
- addl C(paintbuffer)+psp_left-psp_size(,%ecx,psp_size),%edi
- addl C(paintbuffer)+psp_right-psp_size(,%ecx,psp_size),%ebp
- movb -2(%esi,%ecx,1),%bl
- movl %edi,C(paintbuffer)+psp_left-psp_size(,%ecx,psp_size)
- movl %ebp,C(paintbuffer)+psp_right-psp_size(,%ecx,psp_size)
-
- movl (%eax,%ebx,4),%edi
- movl (%edx,%ebx,4),%ebp
- movb -3(%esi,%ecx,1),%bl
- addl C(paintbuffer)+psp_left-psp_size*2(,%ecx,psp_size),%edi
- addl C(paintbuffer)+psp_right-psp_size*2(,%ecx,psp_size),%ebp
- movl %edi,C(paintbuffer)+psp_left-psp_size*2(,%ecx,psp_size)
- movl %ebp,C(paintbuffer)+psp_right-psp_size*2(,%ecx,psp_size)
-
- // }
- subl $2,%ecx
- jnz LMix8Loop
-
- LDone:
- popl %ebp
- popl %ebx
- popl %edi
- popl %esi
-
- ret
-
-
- //----------------------------------------------------------------------
- // Transfer of stereo buffer to 16-bit DMA buffer code
- //----------------------------------------------------------------------
-
- .globl C(Snd_WriteLinearBlastStereo16)
- C(Snd_WriteLinearBlastStereo16):
- pushl %esi // preserve register variables
- pushl %edi
- pushl %ebx
-
- // int i;
- // int val;
- movl C(snd_linear_count),%ecx
- movl C(snd_p),%ebx
- movl C(snd_vol),%esi
- movl C(snd_out),%edi
-
- // for (i=0 ; i<snd_linear_count ; i+=2)
- // {
- LWLBLoopTop:
-
- // val = (snd_p[i]*snd_vol)>>8;
- // if (val > 0x7fff)
- // snd_out[i] = 0x7fff;
- // else if (val < (short)0x8000)
- // snd_out[i] = (short)0x8000;
- // else
- // snd_out[i] = val;
- movl -8(%ebx,%ecx,4),%eax
- imull %esi,%eax
- sarl $8,%eax
- cmpl $0x7FFF,%eax
- jg LClampHigh
- cmpl $0xFFFF8000,%eax
- jnl LClampDone
- movl $0xFFFF8000,%eax
- jmp LClampDone
- LClampHigh:
- movl $0x7FFF,%eax
- LClampDone:
-
- // val = (snd_p[i+1]*snd_vol)>>8;
- // if (val > 0x7fff)
- // snd_out[i+1] = 0x7fff;
- // else if (val < (short)0x8000)
- // snd_out[i+1] = (short)0x8000;
- // else
- // snd_out[i+1] = val;
- movl -4(%ebx,%ecx,4),%edx
- imull %esi,%edx
- sarl $8,%edx
- cmpl $0x7FFF,%edx
- jg LClampHigh2
- cmpl $0xFFFF8000,%edx
- jnl LClampDone2
- movl $0xFFFF8000,%edx
- jmp LClampDone2
- LClampHigh2:
- movl $0x7FFF,%edx
- LClampDone2:
- shll $16,%edx
- andl $0xFFFF,%eax
- orl %eax,%edx
- movl %edx,-4(%edi,%ecx,2)
-
- // }
- subl $2,%ecx
- jnz LWLBLoopTop
-
- // snd_p += snd_linear_count;
-
- popl %ebx
- popl %edi
- popl %esi
-
- ret
-
-
- #endif // id386
-
-