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view src/audio/SDL_mixer_MMX.c @ 1057:e9d23bb80140

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Date: Mon, 02 May 2005 04:23:16 -0500 From: Jonathan Atkins Subject: Re: [PATCH] *CRITICAL* 8bit direct RGB palette not being created I think that SDL_AllocFormat should create the palette for all 8bit surfaces. And when the RGBAmasks match the normal 3:3:2:0 we need to apply the old behavior. If the mask doesn't match that, then we need to make the right palette assuming the masks are valid (I don't think we validate any masks for high color surfaces...so we wouldn't here) Then there's always a palette available for the 8bit surfaces. This restores the normal behavior and allows for masks to create palettes automatically for odd masks even, which would be a neato thing to have in there, as SDL never did this before.
author Sam Lantinga <slouken@libsdl.org>
date Mon, 16 May 2005 05:34:58 +0000
parents e3b3130f3af8
children b580f7201543
line wrap: on
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/*
    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)
    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
***********************************************/

#if defined(i386) && defined(__GNUC__) && defined(USE_ASMBLIT)
void SDL_MixAudio_MMX_S16(char* dst,char* src,unsigned int size,int volume)
{
    __asm__ __volatile__ (

"	movl %3,%%eax\n"	// eax = volume

"	movl %2,%%edx\n"	// edx = size

"	shrl $4,%%edx\n"	// process 16 bytes per iteration = 8 samples

"	jz .endS16\n"

"	pxor %%mm0,%%mm0\n"

"	movd %%eax,%%mm0\n"
"	movq %%mm0,%%mm1\n"
"	psllq $16,%%mm0\n"
"	por %%mm1,%%mm0\n"
"	psllq $16,%%mm0\n"
"	por %%mm1,%%mm0\n"
"	psllq $16,%%mm0\n"
"	por %%mm1,%%mm0\n"		// mm0 = vol|vol|vol|vol

".align 16\n"
"	.mixloopS16:\n"

"	movq (%1),%%mm1\n" // mm1 = a|b|c|d

"	movq %%mm1,%%mm2\n" // mm2 = a|b|c|d

"	movq 8(%1),%%mm4\n" // mm4 = e|f|g|h

	// pré charger le buffer dst dans mm7
"	movq (%0),%%mm7\n" // mm7 = dst[0]"

	// multiplier par le volume
"	pmullw %%mm0,%%mm1\n" // mm1 = l(a*v)|l(b*v)|l(c*v)|l(d*v)

"	pmulhw %%mm0,%%mm2\n" // mm2 = h(a*v)|h(b*v)|h(c*v)|h(d*v)
"	movq %%mm4,%%mm5\n" // mm5 = e|f|g|h

"	pmullw %%mm0,%%mm4\n" // mm4 = l(e*v)|l(f*v)|l(g*v)|l(h*v)

"	pmulhw %%mm0,%%mm5\n" // mm5 = h(e*v)|h(f*v)|h(g*v)|h(h*v)
"	movq %%mm1,%%mm3\n" // mm3 = l(a*v)|l(b*v)|l(c*v)|l(d*v)

"	punpckhwd %%mm2,%%mm1\n" // mm1 = a*v|b*v

"	movq %%mm4,%%mm6\n" // mm6 = l(e*v)|l(f*v)|l(g*v)|l(h*v)
"	punpcklwd %%mm2,%%mm3\n" // mm3 = c*v|d*v

"	punpckhwd %%mm5,%%mm4\n" // mm4 = e*f|f*v

"	punpcklwd %%mm5,%%mm6\n" // mm6 = g*v|h*v

	// pré charger le buffer dst dans mm5
"	movq 8(%0),%%mm5\n" // mm5 = dst[1]

	// diviser par 128
"	psrad $7,%%mm1\n" // mm1 = a*v/128|b*v/128 , 128 = SDL_MIX_MAXVOLUME
"	add $16,%1\n"

"	psrad $7,%%mm3\n" // mm3 = c*v/128|d*v/128

"	psrad $7,%%mm4\n" // mm4 = e*v/128|f*v/128

	// mm1 = le sample avec le volume modifié
"	packssdw %%mm1,%%mm3\n" // mm3 = s(a*v|b*v|c*v|d*v)

"	psrad $7,%%mm6\n" // mm6= g*v/128|h*v/128
"	paddsw %%mm7,%%mm3\n" // mm3 = adjust_volume(src)+dst

	// mm4 = le sample avec le volume modifié
"	packssdw %%mm4,%%mm6\n" // mm6 = s(e*v|f*v|g*v|h*v)
"	movq %%mm3,(%0)\n"

"	paddsw %%mm5,%%mm6\n" // mm6 = adjust_volume(src)+dst

"	movq %%mm6,8(%0)\n"

"	add $16,%0\n"

"	dec %%edx\n"

"	jnz .mixloopS16\n"

"	emms\n"

".endS16:\n"
	 :
	 : "r" (dst), "r"(src),"m"(size),
	 "m"(volume)
	 : "eax","edx","memory"
	 );
}



////////////////////////////////////////////////
// Mixing for 8 bit signed buffers
////////////////////////////////////////////////

void SDL_MixAudio_MMX_S8(char* dst,char* src,unsigned int size,int volume)
{
    __asm__ __volatile__ (

"	movl %3,%%eax\n"	// eax = volume

"	movd %%edx,%%mm0\n"
"	movq %%mm0,%%mm1\n"
"	psllq $16,%%mm0\n"
"	por %%mm1,%%mm0\n"
"	psllq $16,%%mm0\n"
"	por %%mm1,%%mm0\n"
"	psllq $16,%%mm0\n"
"	por %%mm1,%%mm0\n"

"	movl %2,%%edx\n"	// edx = size
"	shr $3,%%edx\n"	// process 8 bytes per iteration = 8 samples

"	cmp $0,%%edx\n"
"	je .endS8\n"

".align 16\n"
"	.mixloopS8:\n"

"	pxor %%mm2,%%mm2\n"		// mm2 = 0
"	movq (%1),%%mm1\n"	// mm1 = a|b|c|d|e|f|g|h

"	movq %%mm1,%%mm3\n" 	// 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 %%mm1,%%mm2\n"	// mm2 = 11111111|00000000|00000000....

"	punpckhbw %%mm2,%%mm1\n"	// mm1 = 0|a|0|b|0|c|0|d

"	punpcklbw %%mm2,%%mm3\n"	// mm3 = 0|e|0|f|0|g|0|h
"	movq (%0),%%mm2\n"	// mm2 = destination

"	pmullw %%mm0,%%mm1\n"	// mm1 = v*a|v*b|v*c|v*d
"	add $8,%1\n"

"	pmullw %%mm0,%%mm3\n"	// mm3 = v*e|v*f|v*g|v*h
"	psraw $7,%%mm1\n"		// mm1 = v*a/128|v*b/128|v*c/128|v*d/128 

"	psraw $7,%%mm3\n"		// mm3 = v*e/128|v*f/128|v*g/128|v*h/128

"	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

"	paddsb %%mm2,%%mm3\n"	// add to destination buffer

"	movq %%mm3,(%0)\n"	// store back to ram
"	add $8,%0\n"

"	dec %%edx\n"

"	jnz .mixloopS8\n"

".endS8:\n"
"	emms\n"
	 :
	 : "r" (dst), "r"(src),"m"(size),
	 "m"(volume)
	 : "eax","edx","memory"
	 );
}
#endif