FFmpeg/libavcodec/alpha/dsputil_alpha.c

/*
 * Alpha optimized DSP utils
 * Copyright (c) 2002 Falk Hueffner <falk@debian.org>
 *
 * 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 "asm.h"
#include "../dsputil.h"

void simple_idct_axp(DCTELEM *block);

void put_pixels_axp_asm(uint8_t *block, const uint8_t *pixels,
			int line_size, int h);
void put_pixels_clamped_mvi_asm(const DCTELEM *block, uint8_t *pixels,
				int line_size);
void add_pixels_clamped_mvi_asm(const DCTELEM *block, uint8_t *pixels, 
				int line_size);

#if 0
/* These functions were the base for the optimized assembler routines,
   and remain here for documentation purposes.  */
static void put_pixels_clamped_mvi(const DCTELEM *block, uint8_t *pixels, 
                                   int line_size)
{
    int i = 8;
    uint64_t clampmask = zap(-1, 0xaa); /* 0x00ff00ff00ff00ff */

    ASM_ACCEPT_MVI;

    do {
        uint64_t shorts0, shorts1;

        shorts0 = ldq(block);
        shorts0 = maxsw4(shorts0, 0);
        shorts0 = minsw4(shorts0, clampmask);
        stl(pkwb(shorts0), pixels);

        shorts1 = ldq(block + 4);
        shorts1 = maxsw4(shorts1, 0);
        shorts1 = minsw4(shorts1, clampmask);
        stl(pkwb(shorts1), pixels + 4);

        pixels += line_size;
        block += 8;
    } while (--i);
}

void add_pixels_clamped_mvi(const DCTELEM *block, uint8_t *pixels, 
                            int line_size)
{
    int h = 8;
    /* Keep this function a leaf function by generating the constants
       manually (mainly for the hack value ;-).  */
    uint64_t clampmask = zap(-1, 0xaa); /* 0x00ff00ff00ff00ff */
    uint64_t signmask  = zap(-1, 0x33);
    signmask ^= signmask >> 1;  /* 0x8000800080008000 */

    ASM_ACCEPT_MVI;

    do {
        uint64_t shorts0, pix0, signs0;
        uint64_t shorts1, pix1, signs1;

        shorts0 = ldq(block);
        shorts1 = ldq(block + 4);

        pix0    = unpkbw(ldl(pixels));
        /* Signed subword add (MMX paddw).  */
        signs0  = shorts0 & signmask;
        shorts0 &= ~signmask;
        shorts0 += pix0;
        shorts0 ^= signs0;
        /* Clamp. */
        shorts0 = maxsw4(shorts0, 0);
        shorts0 = minsw4(shorts0, clampmask);   

        /* Next 4.  */
        pix1    = unpkbw(ldl(pixels + 4));
        signs1  = shorts1 & signmask;
        shorts1 &= ~signmask;
        shorts1 += pix1;
        shorts1 ^= signs1;
        shorts1 = maxsw4(shorts1, 0);
        shorts1 = minsw4(shorts1, clampmask);

        stl(pkwb(shorts0), pixels);
        stl(pkwb(shorts1), pixels + 4);

        pixels += line_size;
        block += 8;
    } while (--h);
}
#endif

static void clear_blocks_axp(DCTELEM *blocks) {
    uint64_t *p = (uint64_t *) blocks;
    int n = sizeof(DCTELEM) * 6 * 64;

    do {
        p[0] = 0;
        p[1] = 0;
        p[2] = 0;
        p[3] = 0;
        p[4] = 0;
        p[5] = 0;
        p[6] = 0;
        p[7] = 0;
        p += 8;
        n -= 8 * 8;
    } while (n);
}

static inline uint64_t avg2_no_rnd(uint64_t a, uint64_t b)
{
    return (a & b) + (((a ^ b) & BYTE_VEC(0xfe)) >> 1);
}

static inline uint64_t avg2(uint64_t a, uint64_t b)
{
    return (a | b) - (((a ^ b) & BYTE_VEC(0xfe)) >> 1);    
}

static inline uint64_t avg4(uint64_t l1, uint64_t l2, uint64_t l3, uint64_t l4)
{
    uint64_t r1 = ((l1 & ~BYTE_VEC(0x03)) >> 2)
		+ ((l2 & ~BYTE_VEC(0x03)) >> 2)
		+ ((l3 & ~BYTE_VEC(0x03)) >> 2)
		+ ((l4 & ~BYTE_VEC(0x03)) >> 2);
    uint64_t r2 = ((  (l1 & BYTE_VEC(0x03))
		    + (l2 & BYTE_VEC(0x03))
		    + (l3 & BYTE_VEC(0x03))
		    + (l4 & BYTE_VEC(0x03))
		    + BYTE_VEC(0x02)) >> 2) & BYTE_VEC(0x03);
    return r1 + r2;
}

static inline uint64_t avg4_no_rnd(uint64_t l1, uint64_t l2,
				   uint64_t l3, uint64_t l4)
{
    uint64_t r1 = ((l1 & ~BYTE_VEC(0x03)) >> 2)
		+ ((l2 & ~BYTE_VEC(0x03)) >> 2)
		+ ((l3 & ~BYTE_VEC(0x03)) >> 2)
		+ ((l4 & ~BYTE_VEC(0x03)) >> 2);
    uint64_t r2 = ((  (l1 & BYTE_VEC(0x03))
		    + (l2 & BYTE_VEC(0x03))
		    + (l3 & BYTE_VEC(0x03))
		    + (l4 & BYTE_VEC(0x03))
		    + BYTE_VEC(0x01)) >> 2) & BYTE_VEC(0x03);
    return r1 + r2;
}

#define OP(LOAD, STORE, INCR)			\
    do {					\
	STORE(LOAD(pixels), block);		\
	pixels += line_size;			\
	block += INCR;				\
    } while (--h)

#define OP_X2(LOAD, STORE, INCR)				\
    do {							\
	uint64_t pix1, pix2;					\
								\
	pix1 = LOAD(pixels);					\
	pix2 = pix1 >> 8 | ((uint64_t) pixels[8] << 56);	\
	STORE(AVG2(pix1, pix2), block);				\
	pixels += line_size;					\
	block += INCR;						\
    } while (--h)

#define OP_Y2(LOAD, STORE, INCR)		\
    do {					\
	uint64_t pix = LOAD(pixels);		\
	do {					\
	    uint64_t next_pix;			\
						\
	    pixels += line_size;		\
	    next_pix = LOAD(pixels);		\
	    STORE(AVG2(pix, next_pix), block);	\
	    block += INCR;			\
	    pix = next_pix;			\
	} while (--h);				\
    } while (0)

#define OP_XY2(LOAD, STORE, INCR)					\
    do {								\
	uint64_t pix1 = LOAD(pixels);					\
	uint64_t pix2 = pix1 >> 8 | ((uint64_t) pixels[8] << 56);	\
									\
	do {								\
	    uint64_t next_pix1, next_pix2;				\
									\
	    pixels += line_size;					\
	    next_pix1 = LOAD(pixels);					\
	    next_pix2 = next_pix1 >> 8 | ((uint64_t) pixels[8] << 56);	\
									\
	    STORE(AVG4(pix1, pix2, next_pix1, next_pix2), block);	\
									\
	    block += INCR;						\
	    pix1 = next_pix1;						\
	    pix2 = next_pix2;						\
	} while (--h);							\
    } while (0)

#define MAKE_OP(BTYPE, OPNAME, SUFF, OPKIND, STORE, INCR)		\
static void OPNAME ## _pixels ## SUFF ## _axp(BTYPE *block,		\
					      const uint8_t *pixels,	\
					      int line_size, int h)	\
{									\
    if ((size_t) pixels & 0x7) {					\
	OPKIND(uldq, STORE, INCR);					\
    } else {								\
	OPKIND(ldq, STORE, INCR);					\
    }									\
}

#define PIXOP(BTYPE, OPNAME, STORE, INCR)		\
    MAKE_OP(BTYPE, OPNAME, ,	 OP,	 STORE, INCR);	\
    MAKE_OP(BTYPE, OPNAME, _x2,	 OP_X2,	 STORE, INCR);	\
    MAKE_OP(BTYPE, OPNAME, _y2,	 OP_Y2,	 STORE, INCR);	\
    MAKE_OP(BTYPE, OPNAME, _xy2, OP_XY2, STORE, INCR);

/* Rounding primitives.  */
#define AVG2 avg2
#define AVG4 avg4
#define STORE(l, b) stq(l, b)
PIXOP(uint8_t, put, STORE, line_size);

#undef STORE
#define STORE(l, b) stq(AVG2(l, ldq(b)), b);
PIXOP(uint8_t, avg, STORE, line_size);

/* Not rounding primitives.  */
#undef AVG2
#undef AVG4
#undef STORE
#define AVG2 avg2_no_rnd
#define AVG4 avg4_no_rnd
#define STORE(l, b) stq(l, b)
PIXOP(uint8_t, put_no_rnd, STORE, line_size);

#undef STORE
#define STORE(l, b) stq(AVG2(l, ldq(b)), b);
PIXOP(uint8_t, avg_no_rnd, STORE, line_size);

void dsputil_init_alpha(void)
{
    put_pixels_tab[0] = put_pixels_axp_asm;
    put_pixels_tab[1] = put_pixels_x2_axp;
    put_pixels_tab[2] = put_pixels_y2_axp;
    put_pixels_tab[3] = put_pixels_xy2_axp;

    put_no_rnd_pixels_tab[0] = put_pixels_axp_asm;
    put_no_rnd_pixels_tab[1] = put_no_rnd_pixels_x2_axp;
    put_no_rnd_pixels_tab[2] = put_no_rnd_pixels_y2_axp;
    put_no_rnd_pixels_tab[3] = put_no_rnd_pixels_xy2_axp;

    avg_pixels_tab[0] = avg_pixels_axp;
    avg_pixels_tab[1] = avg_pixels_x2_axp;
    avg_pixels_tab[2] = avg_pixels_y2_axp;
    avg_pixels_tab[3] = avg_pixels_xy2_axp;

    avg_no_rnd_pixels_tab[0] = avg_no_rnd_pixels_axp;
    avg_no_rnd_pixels_tab[1] = avg_no_rnd_pixels_x2_axp;
    avg_no_rnd_pixels_tab[2] = avg_no_rnd_pixels_y2_axp;
    avg_no_rnd_pixels_tab[3] = avg_no_rnd_pixels_xy2_axp;

    clear_blocks = clear_blocks_axp;

    /* amask clears all bits that correspond to present features.  */
    if (amask(AMASK_MVI) == 0) {
        put_pixels_clamped = put_pixels_clamped_mvi_asm;
        add_pixels_clamped = add_pixels_clamped_mvi_asm;
    }
}