idct_sh4.c

Trolltech公司发布的图形界面操作系统。可在qt-embedded-2.3.10平台上编译为嵌入式图形界面操作系统。

/*
 * idct for sh4
 *
 * Copyright (c) 2001-2003 BERO <[e-mail]>
 *
 * 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 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include "../dsputil.h"
#define c1	1.38703984532214752434	/* sqrt(2)*cos(1*pi/16) */
#define c2	1.30656296487637657577	/* sqrt(2)*cos(2*pi/16) */
#define c3	1.17587560241935884520	/* sqrt(2)*cos(3*pi/16) */
#define c4	1.00000000000000000000	/* sqrt(2)*cos(4*pi/16) */
#define c5	0.78569495838710234903	/* sqrt(2)*cos(5*pi/16) */
#define c6	0.54119610014619712324	/* sqrt(2)*cos(6*pi/16) */
#define c7	0.27589937928294311353	/* sqrt(2)*cos(7*pi/16) */

const	static float even_table[] __attribute__ ((aligned(8))) = {
	 c4, c4, c4, c4,
	 c2, c6,-c6,-c2,
	 c4,-c4,-c4, c4,
	 c6,-c2, c2,-c6
};

const	static float odd_table[] __attribute__ ((aligned(8))) = {
	 c1, c3, c5, c7,
	 c3,-c7,-c1,-c5,
	 c5,-c1, c7, c3,
	 c7,-c5, c3,-c1
};

#undef	c1
#undef	c2
#undef	c3
#undef	c4
#undef	c5
#undef	c6
#undef	c7

#if defined(__SH4_SINGLE__) || defined(__SH4_SINGLE_ONLY__)

#define	load_matrix(table) \
	__asm__ volatile( \
	"	fschg\n" \
	"	fmov	@%0+,xd0\n" \
	"	fmov	@%0+,xd2\n" \
	"	fmov	@%0+,xd4\n" \
	"	fmov	@%0+,xd6\n" \
	"	fmov	@%0+,xd8\n" \
	"	fmov	@%0+,xd10\n" \
	"	fmov	@%0+,xd12\n" \
	"	fmov	@%0+,xd14\n" \
	"	fschg\n" \
	:\
	: "r"(table)\
	: "0" \
	)

#define	ftrv() \
		__asm__ volatile("ftrv xmtrx,fv0" \
		: "=f"(fr0),"=f"(fr1),"=f"(fr2),"=f"(fr3) \
		:  "0"(fr0), "1"(fr1), "2"(fr2), "3"(fr3) );

#define	DEFREG	\
	register float fr0 __asm__("fr0"); \
	register float fr1 __asm__("fr1"); \
	register float fr2 __asm__("fr2"); \
	register float fr3 __asm__("fr3")

#else

/* generic C code for check */

static void ftrv_(const float xf[],float fv[])
{
	float f0,f1,f2,f3;
	f0 = fv[0];
	f1 = fv[1];
	f2 = fv[2];
	f3 = fv[3];
	fv[0] = xf[0]*f0 + xf[4]*f1 + xf[ 8]*f2 + xf[12]*f3;
	fv[1] = xf[1]*f0 + xf[5]*f1 + xf[ 9]*f2 + xf[13]*f3;
	fv[2] = xf[2]*f0 + xf[6]*f1 + xf[10]*f2 + xf[14]*f3;
	fv[3] = xf[3]*f0 + xf[7]*f1 + xf[11]*f2 + xf[15]*f3;
}

static void load_matrix_(float xf[],const float table[])
{
	int i;
	for(i=0;i<16;i++) xf[i]=table[i];
}

#define	ftrv()	ftrv_(xf,fv)
#define	load_matrix(table)	load_matrix_(xf,table)

#define	DEFREG \
	float fv[4],xf[16]

#define	fr0	fv[0]
#define	fr1	fv[1]
#define	fr2	fv[2]
#define	fr3	fv[3]

#endif

#if 1
#define	DESCALE(x,n)	(x)*(1.0f/(1<<(n)))
#else
#define	DESCALE(x,n)	(((int)(x)+(1<<(n-1)))>>(n))
#endif

/* this code work worse on gcc cvs. 3.2.3 work fine */


#if 1
//optimized 

void idct_sh4(DCTELEM *block)
{
	DEFREG;

	int i;
	float	tblock[8*8],*fblock;
	int ofs1,ofs2,ofs3;

#if defined(__SH4__)
#error	"FIXME!! change to single float"
#endif

	/* row */

	/* even part */
	load_matrix(even_table);

	fblock = tblock+4;
	i = 8;
	do {
		fr0 = block[0];
		fr1 = block[2];
		fr2 = block[4];
		fr3 = block[6];
		block+=8;
		ftrv();
		*--fblock = fr3;
		*--fblock = fr2;
		*--fblock = fr1;
		*--fblock = fr0;
		fblock+=8+4;
	} while(--i);
	block-=8*8;
	fblock-=8*8+4;

	load_matrix(odd_table);

	i = 8;

//	ofs1 = sizeof(float)*1;
//	ofs2 = sizeof(float)*2;
//	ofs3 = sizeof(float)*3;

	do {
		float t0,t1,t2,t3;
		fr0 = block[1];
		fr1 = block[3];
		fr2 = block[5];
		fr3 = block[7];
		block+=8;
		ftrv();
		t0 = *fblock++;
		t1 = *fblock++;
		t2 = *fblock++;
		t3 = *fblock++;
		fblock+=4;
		*--fblock = t0 - fr0;
		*--fblock = t1 - fr1;
		*--fblock = t2 - fr2;
		*--fblock = t3 - fr3;
		*--fblock = t3 + fr3;
		*--fblock = t2 + fr2;
		*--fblock = t1 + fr1;
		*--fblock = t0 + fr0;
		fblock+=8;
	} while(--i);
	block-=8*8;
	fblock-=8*8;

	/* col */

	/* even part */
	load_matrix(even_table);

	ofs1 = sizeof(float)*2*8;
	ofs2 = sizeof(float)*4*8;
	ofs3 = sizeof(float)*6*8;

	i = 8;

#define	OA(fblock,ofs)	*(float*)((char*)fblock + ofs)

	do {
		fr0 = OA(fblock,   0);
		fr1 = OA(fblock,ofs1);
		fr2 = OA(fblock,ofs2);
		fr3 = OA(fblock,ofs3);
		ftrv();
		OA(fblock,0   ) = fr0;
		OA(fblock,ofs1) = fr1;
		OA(fblock,ofs2) = fr2;
		OA(fblock,ofs3) = fr3;
		fblock++;
	} while(--i);
	fblock-=8;

	load_matrix(odd_table);

	i=8;
	do {
		float t0,t1,t2,t3;
		t0 = OA(fblock,   0); /* [8*0] */
		t1 = OA(fblock,ofs1); /* [8*2] */
		t2 = OA(fblock,ofs2); /* [8*4] */
		t3 = OA(fblock,ofs3); /* [8*6] */
		fblock+=8;
		fr0 = OA(fblock,   0); /* [8*1] */
		fr1 = OA(fblock,ofs1); /* [8*3] */
		fr2 = OA(fblock,ofs2); /* [8*5] */
		fr3 = OA(fblock,ofs3); /* [8*7] */
		fblock+=-8+1;
		ftrv();
		block[8*0] = DESCALE(t0 + fr0,3);
		block[8*7] = DESCALE(t0 - fr0,3);
		block[8*1] = DESCALE(t1 + fr1,3);
		block[8*6] = DESCALE(t1 - fr1,3);
		block[8*2] = DESCALE(t2 + fr2,3);
		block[8*5] = DESCALE(t2 - fr2,3);
		block[8*3] = DESCALE(t3 + fr3,3);
		block[8*4] = DESCALE(t3 - fr3,3);
		block++;
	} while(--i);

#if defined(__SH4__)
#error	"FIXME!! change to double"
#endif
}
#else
void idct_sh4(DCTELEM *block)
{
	DEFREG;

	int i;
	float	tblock[8*8],*fblock;

	/* row */

	/* even part */
	load_matrix(even_table);

	fblock = tblock;
	i = 8;
	do {
		fr0 = block[0];
		fr1 = block[2];
		fr2 = block[4];
		fr3 = block[6];
		block+=8;
		ftrv();
		fblock[0] = fr0;
		fblock[2] = fr1;
		fblock[4] = fr2;
		fblock[6] = fr3;
		fblock+=8;
	} while(--i);
	block-=8*8;
	fblock-=8*8;

	load_matrix(odd_table);

	i = 8;

	do {
		float t0,t1,t2,t3;
		fr0 = block[1];
		fr1 = block[3];
		fr2 = block[5];
		fr3 = block[7];
		block+=8;
		ftrv();
		t0 = fblock[0];
		t1 = fblock[2];
		t2 = fblock[4];
		t3 = fblock[6];
		fblock[0] = t0 + fr0;
		fblock[7] = t0 - fr0;
		fblock[1] = t1 + fr1;
		fblock[6] = t1 - fr1;
		fblock[2] = t2 + fr2;
		fblock[5] = t2 - fr2;
		fblock[3] = t3 + fr3;
		fblock[4] = t3 - fr3;
		fblock+=8;
	} while(--i);
	block-=8*8;
	fblock-=8*8;

	/* col */

	/* even part */
	load_matrix(even_table);

	i = 8;

	do {
		fr0 = fblock[8*0];
		fr1 = fblock[8*2];
		fr2 = fblock[8*4];
		fr3 = fblock[8*6];
		ftrv();
		fblock[8*0] = fr0;
		fblock[8*2] = fr1;
		fblock[8*4] = fr2;
		fblock[8*6] = fr3;
		fblock++;
	} while(--i);
	fblock-=8;

	load_matrix(odd_table);

	i=8;
	do {
		float t0,t1,t2,t3;
		fr0 = fblock[8*1];
		fr1 = fblock[8*3];
		fr2 = fblock[8*5];
		fr3 = fblock[8*7];
		ftrv();
		t0 = fblock[8*0];
		t1 = fblock[8*2];
		t2 = fblock[8*4];
		t3 = fblock[8*6];
		fblock++;
		block[8*0] = DESCALE(t0 + fr0,3);
		block[8*7] = DESCALE(t0 - fr0,3);
		block[8*1] = DESCALE(t1 + fr1,3);
		block[8*6] = DESCALE(t1 - fr1,3);
		block[8*2] = DESCALE(t2 + fr2,3);
		block[8*5] = DESCALE(t2 - fr2,3);
		block[8*3] = DESCALE(t3 + fr3,3);
		block[8*4] = DESCALE(t3 - fr3,3);
		block++;
	} while(--i);
}
#endif