/* SDL - Simple DirectMedia Layer Copyright (C) 1997-2006 Sam Lantinga This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA Sam Lantinga slouken@libsdl.org */ #include "SDL_config.h" #include "SDL_mixer_MMX_VC.h" #if ((defined(_MSC_VER) && defined(_M_IX86)) || defined(__WATCOMC__)) && defined(SDL_ASSEMBLY_ROUTINES) // MMX assembler version of SDL_MixAudio for signed little endian 16 bit samples and signed 8 bit samples // Copyright 2002 Stephane Marchesin (stephane.marchesin@wanadoo.fr) // Converted to Intel ASM notation by Cth // This code is licensed under the LGPL (see COPYING for details) // // Assumes buffer size in bytes is a multiple of 16 // Assumes SDL_MIX_MAXVOLUME = 128 //////////////////////////////////////////////// // Mixing for 16 bit signed buffers //////////////////////////////////////////////// void SDL_MixAudio_MMX_S16_VC(char* dst,char* src,unsigned int nSize,int volume) { __asm { push edi push esi push ebx mov edi, dst // edi = dst mov esi, src // esi = src mov eax, volume // eax = volume mov ebx, nSize // ebx = size shr ebx, 4 // process 16 bytes per iteration = 8 samples jz endS16 pxor mm0, mm0 movd mm0, eax //%%eax,%%mm0 movq mm1, mm0 //%%mm0,%%mm1 psllq mm0, 16 //$16,%%mm0 por mm0, mm1 //%%mm1,%%mm0 psllq mm0, 16 //$16,%%mm0 por mm0, mm1 //%%mm1,%%mm0 psllq mm0, 16 //$16,%%mm0 por mm0, mm1 //%%mm1,%%mm0 // mm0 = vol|vol|vol|vol #ifndef __WATCOMC__ align 16 #endif mixloopS16: movq mm1, [esi] //(%%esi),%%mm1\n" // mm1 = a|b|c|d movq mm2, mm1 //%%mm1,%%mm2\n" // mm2 = a|b|c|d movq mm4, [esi + 8] //8(%%esi),%%mm4\n" // mm4 = e|f|g|h // pre charger le buffer dst dans mm7 movq mm7, [edi] //(%%edi),%%mm7\n" // mm7 = dst[0]" // multiplier par le volume pmullw mm1, mm0 //%%mm0,%%mm1\n" // mm1 = l(a*v)|l(b*v)|l(c*v)|l(d*v) pmulhw mm2, mm0 //%%mm0,%%mm2\n" // mm2 = h(a*v)|h(b*v)|h(c*v)|h(d*v) movq mm5, mm4 //%%mm4,%%mm5\n" // mm5 = e|f|g|h pmullw mm4, mm0 //%%mm0,%%mm4\n" // mm4 = l(e*v)|l(f*v)|l(g*v)|l(h*v) pmulhw mm5, mm0 //%%mm0,%%mm5\n" // mm5 = h(e*v)|h(f*v)|h(g*v)|h(h*v) movq mm3, mm1 //%%mm1,%%mm3\n" // mm3 = l(a*v)|l(b*v)|l(c*v)|l(d*v) punpckhwd mm1, mm2 //%%mm2,%%mm1\n" // mm1 = a*v|b*v movq mm6, mm4 //%%mm4,%%mm6\n" // mm6 = l(e*v)|l(f*v)|l(g*v)|l(h*v) punpcklwd mm3, mm2 //%%mm2,%%mm3\n" // mm3 = c*v|d*v punpckhwd mm4, mm5 //%%mm5,%%mm4\n" // mm4 = e*f|f*v punpcklwd mm6, mm5 //%%mm5,%%mm6\n" // mm6 = g*v|h*v // pre charger le buffer dst dans mm5 movq mm5, [edi + 8] //8(%%edi),%%mm5\n" // mm5 = dst[1] // diviser par 128 psrad mm1, 7 //$7,%%mm1\n" // mm1 = a*v/128|b*v/128 , 128 = SDL_MIX_MAXVOLUME add esi, 16 //$16,%%esi\n" psrad mm3, 7 //$7,%%mm3\n" // mm3 = c*v/128|d*v/128 psrad mm4, 7 //$7,%%mm4\n" // mm4 = e*v/128|f*v/128 // mm1 = le sample avec le volume modifie packssdw mm3, mm1 //%%mm1,%%mm3\n" // mm3 = s(a*v|b*v|c*v|d*v) psrad mm6, 7 //$7,%%mm6\n" // mm6= g*v/128|h*v/128 paddsw mm3, mm7 //%%mm7,%%mm3\n" // mm3 = adjust_volume(src)+dst // mm4 = le sample avec le volume modifie packssdw mm6, mm4 //%%mm4,%%mm6\n" // mm6 = s(e*v|f*v|g*v|h*v) movq [edi], mm3 //%%mm3,(%%edi)\n" paddsw mm6, mm5 //%%mm5,%%mm6\n" // mm6 = adjust_volume(src)+dst movq [edi + 8], mm6 //%%mm6,8(%%edi)\n" add edi, 16 //$16,%%edi\n" dec ebx //%%ebx\n" jnz mixloopS16 ends16: emms pop ebx pop esi pop edi } } //////////////////////////////////////////////// // Mixing for 8 bit signed buffers //////////////////////////////////////////////// void SDL_MixAudio_MMX_S8_VC(char* dst,char* src,unsigned int nSize,int volume) { _asm { push edi push esi push ebx mov edi, dst //movl %0,%%edi // edi = dst mov esi, src //%1,%%esi // esi = src mov eax, volume //%3,%%eax // eax = volume movd mm0, eax //%%eax,%%mm0 movq mm1, mm0 //%%mm0,%%mm1 psllq mm0, 16 //$16,%%mm0 por mm0, mm1 //%%mm1,%%mm0 psllq mm0, 16 //$16,%%mm0 por mm0, mm1 //%%mm1,%%mm0 psllq mm0, 16 //$16,%%mm0 por mm0, mm1 //%%mm1,%%mm0 mov ebx, nSize //%2,%%ebx // ebx = size shr ebx, 3 //$3,%%ebx // process 8 bytes per iteration = 8 samples cmp ebx, 0 //$0,%%ebx je endS8 #ifndef __WATCOMC__ align 16 #endif mixloopS8: pxor mm2, mm2 //%%mm2,%%mm2 // mm2 = 0 movq mm1, [esi] //(%%esi),%%mm1 // mm1 = a|b|c|d|e|f|g|h movq mm3, mm1 //%%mm1,%%mm3 // mm3 = a|b|c|d|e|f|g|h // on va faire le "sign extension" en faisant un cmp avec 0 qui retourne 1 si <0, 0 si >0 pcmpgtb mm2, mm1 //%%mm1,%%mm2 // mm2 = 11111111|00000000|00000000.... punpckhbw mm1, mm2 //%%mm2,%%mm1 // mm1 = 0|a|0|b|0|c|0|d punpcklbw mm3, mm2 //%%mm2,%%mm3 // mm3 = 0|e|0|f|0|g|0|h movq mm2, [edi] //(%%edi),%%mm2 // mm2 = destination pmullw mm1, mm0 //%%mm0,%%mm1 // mm1 = v*a|v*b|v*c|v*d add esi, 8 //$8,%%esi pmullw mm3, mm0 //%%mm0,%%mm3 // mm3 = v*e|v*f|v*g|v*h psraw mm1, 7 //$7,%%mm1 // mm1 = v*a/128|v*b/128|v*c/128|v*d/128 psraw mm3, 7 //$7,%%mm3 // mm3 = v*e/128|v*f/128|v*g/128|v*h/128 packsswb mm3, mm1 //%%mm1,%%mm3 // 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 paddsb mm3, mm2 //%%mm2,%%mm3 // add to destination buffer movq [edi], mm3 //%%mm3,(%%edi) // store back to ram add edi, 8 //$8,%%edi dec ebx //%%ebx jnz mixloopS8 endS8: emms pop ebx pop esi pop edi } } #endif /* SDL_ASSEMBLY_ROUTINES */