1 /* 2 SDL - Simple DirectMedia Layer 3 Copyright (C) 1997-2012 Sam Lantinga 4 5 This library is free software; you can redistribute it and/or 6 modify it under the terms of the GNU Library General Public 7 License as published by the Free Software Foundation; either 8 version 2 of the License, or (at your option) any later version. 9 10 This library is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 Library General Public License for more details. 14 15 You should have received a copy of the GNU Library General Public 16 License along with this library; if not, write to the Free 17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 18 19 Sam Lantinga 20 slouken (at) libsdl.org 21 */ 22 #include "SDL_config.h" 23 24 /* 25 m68k assembly mix routines 26 27 Patrice Mandin 28 */ 29 30 #if (defined(__m68k__) && !defined(__mcoldfire__)) && defined(__GNUC__) 31 void SDL_MixAudio_m68k_U8(char* dst, char* src, long len, long volume, char* mix8) 32 { 33 __asm__ __volatile__ ( 34 35 "tstl %2\n" 36 " beqs stoploop_u8\n" 37 "mixloop_u8:\n" 38 39 /* Mix a sample */ 40 41 " moveq #0,%%d0\n" 42 " moveq #0,%%d1\n" 43 44 " moveb %1@+,%%d0\n" /* d0 = *src++ */ 45 " sub #128,%%d0\n" /* d0 -= 128 */ 46 " muls %3,%%d0\n" /* d0 *= volume (0<=volume<=128) */ 47 " moveb %0@,%%d1\n" /* d1 = *dst */ 48 " asr #7,%%d0\n" /* d0 /= 128 (SDL_MIX_MAXVOLUME) */ 49 " add #128,%%d0\n" /* d0 += 128 */ 50 51 " add %%d1,%%d0\n" 52 53 " moveb %4@(%%d0:w),%0@+\n" 54 55 /* Loop till done */ 56 57 " subql #1,%2\n" 58 " bhis mixloop_u8\n" 59 "stoploop_u8:\n" 60 61 : /* no return value */ 62 : /* input */ 63 "a"(dst), "a"(src), "d"(len), "d"(volume), "a"(mix8) 64 : /* clobbered registers */ 65 "d0", "d1", "cc", "memory" 66 ); 67 } 68 69 void SDL_MixAudio_m68k_S8(char* dst, char* src, long len, long volume) 70 { 71 __asm__ __volatile__ ( 72 73 "tstl %2\n" 74 " beqs stoploop_s8\n" 75 " moveq #-128,%%d2\n" 76 " moveq #127,%%d3\n" 77 "mixloop_s8:\n" 78 79 /* Mix a sample */ 80 81 " moveq #0,%%d0\n" 82 " moveq #0,%%d1\n" 83 84 " moveb %1@+,%%d0\n" /* d0 = *src++ */ 85 " muls %3,%%d0\n" /* d0 *= volume (0<=volume<=128) */ 86 " moveb %0@,%%d1\n" /* d1 = *dst */ 87 " asr #7,%%d0\n" /* d0 /= 128 (SDL_MIX_MAXVOLUME) */ 88 89 " add %%d1,%%d0\n" 90 91 " cmp %%d2,%%d0\n" 92 " bges lower_limit_s8\n" 93 " move %%d2,%%d0\n" 94 "lower_limit_s8:\n" 95 96 " cmp %%d3,%%d0\n" 97 " bles upper_limit_s8\n" 98 " move %%d3,%%d0\n" 99 "upper_limit_s8:\n" 100 " moveb %%d0,%0@+\n" 101 102 /* Loop till done */ 103 104 " subql #1,%2\n" 105 " bhis mixloop_s8\n" 106 "stoploop_s8:\n" 107 108 : /* no return value */ 109 : /* input */ 110 "a"(dst), "a"(src), "d"(len), "d"(volume) 111 : /* clobbered registers */ 112 "d0", "d1", "d2", "d3", "cc", "memory" 113 ); 114 } 115 116 void SDL_MixAudio_m68k_S16MSB(short* dst, short* src, long len, long volume) 117 { 118 __asm__ __volatile__ ( 119 120 "tstl %2\n" 121 " beqs stoploop_s16msb\n" 122 " movel #-32768,%%d2\n" 123 " movel #32767,%%d3\n" 124 " lsrl #1,%2\n" 125 "mixloop_s16msb:\n" 126 127 /* Mix a sample */ 128 129 " move %1@+,%%d0\n" /* d0 = *src++ */ 130 " muls %3,%%d0\n" /* d0 *= volume (0<=volume<=128) */ 131 " move %0@,%%d1\n" /* d1 = *dst */ 132 " extl %%d1\n" /* extend d1 to 32 bits */ 133 " asrl #7,%%d0\n" /* d0 /= 128 (SDL_MIX_MAXVOLUME) */ 134 135 " addl %%d1,%%d0\n" 136 137 " cmpl %%d2,%%d0\n" 138 " bges lower_limit_s16msb\n" 139 " move %%d2,%%d0\n" 140 "lower_limit_s16msb:\n" 141 142 " cmpl %%d3,%%d0\n" 143 " bles upper_limit_s16msb\n" 144 " move %%d3,%%d0\n" 145 "upper_limit_s16msb:\n" 146 " move %%d0,%0@+\n" 147 148 /* Loop till done */ 149 150 " subql #1,%2\n" 151 " bhis mixloop_s16msb\n" 152 "stoploop_s16msb:\n" 153 154 : /* no return value */ 155 : /* input */ 156 "a"(dst), "a"(src), "d"(len), "d"(volume) 157 : /* clobbered registers */ 158 "d0", "d1", "d2", "d3", "cc", "memory" 159 ); 160 } 161 162 void SDL_MixAudio_m68k_S16LSB(short* dst, short* src, long len, long volume) 163 { 164 __asm__ __volatile__ ( 165 166 "tstl %2\n" 167 " beqs stoploop_s16lsb\n" 168 " movel #-32768,%%d2\n" 169 " movel #32767,%%d3\n" 170 " lsrl #1,%2\n" 171 "mixloop_s16lsb:\n" 172 173 /* Mix a sample */ 174 175 " move %1@+,%%d0\n" /* d0 = *src++ */ 176 " rorw #8,%%d0\n" 177 " muls %3,%%d0\n" /* d0 *= volume (0<=volume<=128) */ 178 " move %0@,%%d1\n" /* d1 = *dst */ 179 " rorw #8,%%d1\n" 180 " extl %%d1\n" /* extend d1 to 32 bits */ 181 " asrl #7,%%d0\n" /* d0 /= 128 (SDL_MIX_MAXVOLUME) */ 182 183 " addl %%d1,%%d0\n" 184 185 " cmpl %%d2,%%d0\n" 186 " bges lower_limit_s16lsb\n" 187 " move %%d2,%%d0\n" 188 "lower_limit_s16lsb:\n" 189 190 " cmpl %%d3,%%d0\n" 191 " bles upper_limit_s16lsb\n" 192 " move %%d3,%%d0\n" 193 "upper_limit_s16lsb:\n" 194 " rorw #8,%%d0\n" 195 " move %%d0,%0@+\n" 196 197 /* Loop till done */ 198 199 " subql #1,%2\n" 200 " bhis mixloop_s16lsb\n" 201 "stoploop_s16lsb:\n" 202 203 : /* no return value */ 204 : /* input */ 205 "a"(dst), "a"(src), "d"(len), "d"(volume) 206 : /* clobbered registers */ 207 "d0", "d1", "d2", "d3", "cc", "memory" 208 ); 209 } 210 #endif 211
