| /* |
| SDL - Simple DirectMedia Layer |
| Copyright (C) 1997-2012 Sam Lantinga |
| |
| This library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Library General Public |
| License as published by the Free Software Foundation; either |
| version 2 of the License, or (at your option) any later version. |
| |
| This 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 |
| Library General Public License for more details. |
| |
| You should have received a copy of the GNU Library General Public |
| License along with this library; if not, write to the Free |
| Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| |
| Sam Lantinga |
| slouken@libsdl.org |
| */ |
| #include "SDL_config.h" |
| |
| /* |
| m68k assembly mix routines |
| |
| Patrice Mandin |
| */ |
| |
| #if (defined(__m68k__) && !defined(__mcoldfire__)) && defined(__GNUC__) |
| void SDL_MixAudio_m68k_U8(char* dst, char* src, long len, long volume, char* mix8) |
| { |
| __asm__ __volatile__ ( |
| |
| "tstl %2\n" |
| " beqs stoploop_u8\n" |
| "mixloop_u8:\n" |
| |
| /* Mix a sample */ |
| |
| " moveq #0,%%d0\n" |
| " moveq #0,%%d1\n" |
| |
| " moveb %1@+,%%d0\n" /* d0 = *src++ */ |
| " sub #128,%%d0\n" /* d0 -= 128 */ |
| " muls %3,%%d0\n" /* d0 *= volume (0<=volume<=128) */ |
| " moveb %0@,%%d1\n" /* d1 = *dst */ |
| " asr #7,%%d0\n" /* d0 /= 128 (SDL_MIX_MAXVOLUME) */ |
| " add #128,%%d0\n" /* d0 += 128 */ |
| |
| " add %%d1,%%d0\n" |
| |
| " moveb %4@(%%d0:w),%0@+\n" |
| |
| /* Loop till done */ |
| |
| " subql #1,%2\n" |
| " bhis mixloop_u8\n" |
| "stoploop_u8:\n" |
| |
| : /* no return value */ |
| : /* input */ |
| "a"(dst), "a"(src), "d"(len), "d"(volume), "a"(mix8) |
| : /* clobbered registers */ |
| "d0", "d1", "cc", "memory" |
| ); |
| } |
| |
| void SDL_MixAudio_m68k_S8(char* dst, char* src, long len, long volume) |
| { |
| __asm__ __volatile__ ( |
| |
| "tstl %2\n" |
| " beqs stoploop_s8\n" |
| " moveq #-128,%%d2\n" |
| " moveq #127,%%d3\n" |
| "mixloop_s8:\n" |
| |
| /* Mix a sample */ |
| |
| " moveq #0,%%d0\n" |
| " moveq #0,%%d1\n" |
| |
| " moveb %1@+,%%d0\n" /* d0 = *src++ */ |
| " muls %3,%%d0\n" /* d0 *= volume (0<=volume<=128) */ |
| " moveb %0@,%%d1\n" /* d1 = *dst */ |
| " asr #7,%%d0\n" /* d0 /= 128 (SDL_MIX_MAXVOLUME) */ |
| |
| " add %%d1,%%d0\n" |
| |
| " cmp %%d2,%%d0\n" |
| " bges lower_limit_s8\n" |
| " move %%d2,%%d0\n" |
| "lower_limit_s8:\n" |
| |
| " cmp %%d3,%%d0\n" |
| " bles upper_limit_s8\n" |
| " move %%d3,%%d0\n" |
| "upper_limit_s8:\n" |
| " moveb %%d0,%0@+\n" |
| |
| /* Loop till done */ |
| |
| " subql #1,%2\n" |
| " bhis mixloop_s8\n" |
| "stoploop_s8:\n" |
| |
| : /* no return value */ |
| : /* input */ |
| "a"(dst), "a"(src), "d"(len), "d"(volume) |
| : /* clobbered registers */ |
| "d0", "d1", "d2", "d3", "cc", "memory" |
| ); |
| } |
| |
| void SDL_MixAudio_m68k_S16MSB(short* dst, short* src, long len, long volume) |
| { |
| __asm__ __volatile__ ( |
| |
| "tstl %2\n" |
| " beqs stoploop_s16msb\n" |
| " movel #-32768,%%d2\n" |
| " movel #32767,%%d3\n" |
| " lsrl #1,%2\n" |
| "mixloop_s16msb:\n" |
| |
| /* Mix a sample */ |
| |
| " move %1@+,%%d0\n" /* d0 = *src++ */ |
| " muls %3,%%d0\n" /* d0 *= volume (0<=volume<=128) */ |
| " move %0@,%%d1\n" /* d1 = *dst */ |
| " extl %%d1\n" /* extend d1 to 32 bits */ |
| " asrl #7,%%d0\n" /* d0 /= 128 (SDL_MIX_MAXVOLUME) */ |
| |
| " addl %%d1,%%d0\n" |
| |
| " cmpl %%d2,%%d0\n" |
| " bges lower_limit_s16msb\n" |
| " move %%d2,%%d0\n" |
| "lower_limit_s16msb:\n" |
| |
| " cmpl %%d3,%%d0\n" |
| " bles upper_limit_s16msb\n" |
| " move %%d3,%%d0\n" |
| "upper_limit_s16msb:\n" |
| " move %%d0,%0@+\n" |
| |
| /* Loop till done */ |
| |
| " subql #1,%2\n" |
| " bhis mixloop_s16msb\n" |
| "stoploop_s16msb:\n" |
| |
| : /* no return value */ |
| : /* input */ |
| "a"(dst), "a"(src), "d"(len), "d"(volume) |
| : /* clobbered registers */ |
| "d0", "d1", "d2", "d3", "cc", "memory" |
| ); |
| } |
| |
| void SDL_MixAudio_m68k_S16LSB(short* dst, short* src, long len, long volume) |
| { |
| __asm__ __volatile__ ( |
| |
| "tstl %2\n" |
| " beqs stoploop_s16lsb\n" |
| " movel #-32768,%%d2\n" |
| " movel #32767,%%d3\n" |
| " lsrl #1,%2\n" |
| "mixloop_s16lsb:\n" |
| |
| /* Mix a sample */ |
| |
| " move %1@+,%%d0\n" /* d0 = *src++ */ |
| " rorw #8,%%d0\n" |
| " muls %3,%%d0\n" /* d0 *= volume (0<=volume<=128) */ |
| " move %0@,%%d1\n" /* d1 = *dst */ |
| " rorw #8,%%d1\n" |
| " extl %%d1\n" /* extend d1 to 32 bits */ |
| " asrl #7,%%d0\n" /* d0 /= 128 (SDL_MIX_MAXVOLUME) */ |
| |
| " addl %%d1,%%d0\n" |
| |
| " cmpl %%d2,%%d0\n" |
| " bges lower_limit_s16lsb\n" |
| " move %%d2,%%d0\n" |
| "lower_limit_s16lsb:\n" |
| |
| " cmpl %%d3,%%d0\n" |
| " bles upper_limit_s16lsb\n" |
| " move %%d3,%%d0\n" |
| "upper_limit_s16lsb:\n" |
| " rorw #8,%%d0\n" |
| " move %%d0,%0@+\n" |
| |
| /* Loop till done */ |
| |
| " subql #1,%2\n" |
| " bhis mixloop_s16lsb\n" |
| "stoploop_s16lsb:\n" |
| |
| : /* no return value */ |
| : /* input */ |
| "a"(dst), "a"(src), "d"(len), "d"(volume) |
| : /* clobbered registers */ |
| "d0", "d1", "d2", "d3", "cc", "memory" |
| ); |
| } |
| #endif |
