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 Lesser General Public 7 License as published by the Free Software Foundation; either 8 version 2.1 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 Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public 16 License along with this library; if not, write to the Free Software 17 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 18 19 Sam Lantinga 20 slouken (at) libsdl.org 21 */ 22 #include "SDL_config.h" 23 24 /* 25 MMX assembler version of SDL_MixAudio for signed little endian 16 bit samples and signed 8 bit samples 26 Copyright 2002 Stephane Marchesin (stephane.marchesin (at) wanadoo.fr) 27 This code is licensed under the LGPL (see COPYING for details) 28 29 Assumes buffer size in bytes is a multiple of 16 30 Assumes SDL_MIX_MAXVOLUME = 128 31 */ 32 33 34 /*********************************************** 35 * Mixing for 16 bit signed buffers 36 ***********************************************/ 37 38 #if defined(SDL_BUGGY_MMX_MIXERS) /* buggy, so we're disabling them. --ryan. */ 39 #if defined(__GNUC__) && defined(__i386__) && defined(SDL_ASSEMBLY_ROUTINES) 40 void SDL_MixAudio_MMX_S16(char* dst,char* src,unsigned int size,int volume) 41 { 42 __asm__ __volatile__ ( 43 44 " movl %3,%%eax\n" /* eax = volume */ 45 46 " movl %2,%%edx\n" /* edx = size */ 47 48 " shrl $4,%%edx\n" /* process 16 bytes per iteration = 8 samples */ 49 50 " jz .endS16\n" 51 52 " pxor %%mm0,%%mm0\n" 53 54 " movd %%eax,%%mm0\n" 55 " movq %%mm0,%%mm1\n" 56 " psllq $16,%%mm0\n" 57 " por %%mm1,%%mm0\n" 58 " psllq $16,%%mm0\n" 59 " por %%mm1,%%mm0\n" 60 " psllq $16,%%mm0\n" 61 " por %%mm1,%%mm0\n" /* mm0 = vol|vol|vol|vol */ 62 63 ".align 8\n" 64 " .mixloopS16:\n" 65 66 " movq (%1),%%mm1\n" /* mm1 = a|b|c|d */ 67 68 " movq %%mm1,%%mm2\n" /* mm2 = a|b|c|d */ 69 70 " movq 8(%1),%%mm4\n" /* mm4 = e|f|g|h */ 71 72 /* pr charger le buffer dst dans mm7 */ 73 " movq (%0),%%mm7\n" /* mm7 = dst[0] */ 74 75 /* multiplier par le volume */ 76 " pmullw %%mm0,%%mm1\n" /* mm1 = l(a*v)|l(b*v)|l(c*v)|l(d*v) */ 77 78 " pmulhw %%mm0,%%mm2\n" /* mm2 = h(a*v)|h(b*v)|h(c*v)|h(d*v) */ 79 " movq %%mm4,%%mm5\n" /* mm5 = e|f|g|h */ 80 81 " pmullw %%mm0,%%mm4\n" /* mm4 = l(e*v)|l(f*v)|l(g*v)|l(h*v) */ 82 83 " pmulhw %%mm0,%%mm5\n" /* mm5 = h(e*v)|h(f*v)|h(g*v)|h(h*v) */ 84 " movq %%mm1,%%mm3\n" /* mm3 = l(a*v)|l(b*v)|l(c*v)|l(d*v) */ 85 86 " punpckhwd %%mm2,%%mm1\n" /* mm1 = a*v|b*v */ 87 88 " movq %%mm4,%%mm6\n" /* mm6 = l(e*v)|l(f*v)|l(g*v)|l(h*v) */ 89 " punpcklwd %%mm2,%%mm3\n" /* mm3 = c*v|d*v */ 90 91 " punpckhwd %%mm5,%%mm4\n" /* mm4 = e*f|f*v */ 92 93 " punpcklwd %%mm5,%%mm6\n" /* mm6 = g*v|h*v */ 94 95 /* pr charger le buffer dst dans mm5 */ 96 " movq 8(%0),%%mm5\n" /* mm5 = dst[1] */ 97 98 /* diviser par 128 */ 99 " psrad $7,%%mm1\n" /* mm1 = a*v/128|b*v/128 , 128 = SDL_MIX_MAXVOLUME */ 100 " add $16,%1\n" 101 102 " psrad $7,%%mm3\n" /* mm3 = c*v/128|d*v/128 */ 103 104 " psrad $7,%%mm4\n" /* mm4 = e*v/128|f*v/128 */ 105 106 /* mm1 = le sample avec le volume modifi */ 107 " packssdw %%mm1,%%mm3\n" /* mm3 = s(a*v|b*v|c*v|d*v) */ 108 109 " psrad $7,%%mm6\n" /* mm6= g*v/128|h*v/128 */ 110 " paddsw %%mm7,%%mm3\n" /* mm3 = adjust_volume(src)+dst */ 111 112 /* mm4 = le sample avec le volume modifi */ 113 " packssdw %%mm4,%%mm6\n" /* mm6 = s(e*v|f*v|g*v|h*v) */ 114 " movq %%mm3,(%0)\n" 115 116 " paddsw %%mm5,%%mm6\n" /* mm6 = adjust_volume(src)+dst */ 117 118 " movq %%mm6,8(%0)\n" 119 120 " add $16,%0\n" 121 122 " dec %%edx\n" 123 124 " jnz .mixloopS16\n" 125 126 " emms\n" 127 128 ".endS16:\n" 129 : 130 : "r" (dst), "r"(src),"m"(size), 131 "m"(volume) 132 : "eax","edx","memory" 133 ); 134 } 135 136 137 138 /*////////////////////////////////////////////// */ 139 /* Mixing for 8 bit signed buffers */ 140 /*////////////////////////////////////////////// */ 141 142 void SDL_MixAudio_MMX_S8(char* dst,char* src,unsigned int size,int volume) 143 { 144 __asm__ __volatile__ ( 145 146 " movl %3,%%eax\n" /* eax = volume */ 147 148 " movd %%eax,%%mm0\n" 149 " movq %%mm0,%%mm1\n" 150 " psllq $16,%%mm0\n" 151 " por %%mm1,%%mm0\n" 152 " psllq $16,%%mm0\n" 153 " por %%mm1,%%mm0\n" 154 " psllq $16,%%mm0\n" 155 " por %%mm1,%%mm0\n" 156 157 " movl %2,%%edx\n" /* edx = size */ 158 " shr $3,%%edx\n" /* process 8 bytes per iteration = 8 samples */ 159 160 " cmp $0,%%edx\n" 161 " je .endS8\n" 162 163 ".align 8\n" 164 " .mixloopS8:\n" 165 166 " pxor %%mm2,%%mm2\n" /* mm2 = 0 */ 167 " movq (%1),%%mm1\n" /* mm1 = a|b|c|d|e|f|g|h */ 168 169 " movq %%mm1,%%mm3\n" /* mm3 = a|b|c|d|e|f|g|h */ 170 171 /* on va faire le "sign extension" en faisant un cmp avec 0 qui retourne 1 si <0, 0 si >0 */ 172 " pcmpgtb %%mm1,%%mm2\n" /* mm2 = 11111111|00000000|00000000.... */ 173 174 " punpckhbw %%mm2,%%mm1\n" /* mm1 = 0|a|0|b|0|c|0|d */ 175 176 " punpcklbw %%mm2,%%mm3\n" /* mm3 = 0|e|0|f|0|g|0|h */ 177 " movq (%0),%%mm2\n" /* mm2 = destination */ 178 179 " pmullw %%mm0,%%mm1\n" /* mm1 = v*a|v*b|v*c|v*d */ 180 " add $8,%1\n" 181 182 " pmullw %%mm0,%%mm3\n" /* mm3 = v*e|v*f|v*g|v*h */ 183 " psraw $7,%%mm1\n" /* mm1 = v*a/128|v*b/128|v*c/128|v*d/128 */ 184 185 " psraw $7,%%mm3\n" /* mm3 = v*e/128|v*f/128|v*g/128|v*h/128 */ 186 187 " packsswb %%mm1,%%mm3\n" /* mm1 = v*a/128|v*b/128|v*c/128|v*d/128|v*e/128|v*f/128|v*g/128|v*h/128 */ 188 189 " paddsb %%mm2,%%mm3\n" /* add to destination buffer */ 190 191 " movq %%mm3,(%0)\n" /* store back to ram */ 192 " add $8,%0\n" 193 194 " dec %%edx\n" 195 196 " jnz .mixloopS8\n" 197 198 ".endS8:\n" 199 " emms\n" 200 : 201 : "r" (dst), "r"(src),"m"(size), 202 "m"(volume) 203 : "eax","edx","memory" 204 ); 205 } 206 #endif 207 #endif 208
