Mercurial > sdl-ios-xcode
view src/audio/SDL_mixer_MMX_VC.c @ 1199:2d6dc7de1145
From: Mike Frysinger <vapier@gentoo.org>
To: sdl@libsdl.org
Date: Sun, 11 Dec 2005 22:57:37 -0500
Subject: [SDL] exec stack in libsdl update
i posted back in September a patch to remove executable stacks:
http://www.devolution.com/pipermail/sdl/2005-September/070626.html
later in November, a similar patch was merged it seems:
http://www.libsdl.org/cgi/cvsweb.cgi/SDL12/src/hermes/mmx_main.asm
however, this lacks the additional output format checks that i posted in my
patch ... this isnt a problem if the hermes asm code is only ever used to
produce ELF objects, but if this is not true, then the additional checks in
my original patch will need to be merged
-mike
author | Ryan C. Gordon <icculus@icculus.org> |
---|---|
date | Mon, 12 Dec 2005 09:13:12 +0000 |
parents | 173c063d4f55 |
children | 450721ad5436 |
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#if defined(USE_ASM_MIXER_VC) // 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 //////////////////////////////////////////////// #ifndef __WATCOMC__ #include <windows.h> #include <stdio.h> #endif 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 /* USE_ASM_MIXER_VC */