/*
 * AltiVec-enhanced yuv2yuvX
 *
 * Copyright (C) 2004 Romain Dolbeau <romain@dolbeau.org>
 * based on the equivalent C code in swscale.c
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg 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.
 *
 * FFmpeg 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 FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <inttypes.h>

#include "config.h"
#include "libswscale/swscale.h"
#include "libswscale/swscale_internal.h"
#include "libavutil/attributes.h"
#include "libavutil/cpu.h"
#include "yuv2rgb_altivec.h"
#include "libavutil/ppc/util_altivec.h"

#if HAVE_ALTIVEC && HAVE_BIGENDIAN
#define vzero vec_splat_s32(0)

#define  GET_LS(a,b,c,s) {\
        vector signed short l2  = vec_ld(((b) << 1) + 16, s);\
        ls  = vec_perm(a, l2, c);\
        a = l2;\
    }

#define yuv2planeX_8(d1, d2, l1, src, x, perm, filter) do {\
        vector signed short ls;\
        GET_LS(l1, x, perm, src);\
        vector signed int   i1  = vec_mule(filter, ls);\
        vector signed int   i2  = vec_mulo(filter, ls);\
        vector signed int   vf1, vf2;\
        vf1 = vec_mergeh(i1, i2);\
        vf2 = vec_mergel(i1, i2);\
        d1 = vec_add(d1, vf1);\
        d2 = vec_add(d2, vf2);\
    } while (0)

#define LOAD_FILTER(vf,f) {\
        vector unsigned char perm0 = vec_lvsl(joffset, f);\
        vf = vec_ld(joffset, f);\
        vf = vec_perm(vf, vf, perm0);\
}
#define LOAD_L1(ll1,s,p){\
        p = vec_lvsl(xoffset, s);\
        ll1   = vec_ld(xoffset, s);\
}

// The 3 above is 2 (filterSize == 4) + 1 (sizeof(short) == 2).

// The neat trick: We only care for half the elements,
// high or low depending on (i<<3)%16 (it's 0 or 8 here),
// and we're going to use vec_mule, so we choose
// carefully how to "unpack" the elements into the even slots.
#define GET_VF4(a, vf, f) {\
    vf = vec_ld(a<< 3, f);\
    if ((a << 3) % 16)\
        vf = vec_mergel(vf, (vector signed short)vzero);\
    else\
        vf = vec_mergeh(vf, (vector signed short)vzero);\
}
#define FIRST_LOAD(sv, pos, s, per) {\
    sv = vec_ld(pos, s);\
    per = vec_lvsl(pos, s);\
}
#define UPDATE_PTR(s0, d0, s1, d1) {\
    d0 = s0;\
    d1 = s1;\
}
#define LOAD_SRCV(pos, a, s, per, v0, v1, vf) {\
    v1 = vec_ld(pos + a + 16, s);\
    vf = vec_perm(v0, v1, per);\
}
#define LOAD_SRCV8(pos, a, s, per, v0, v1, vf) {\
    if ((((uintptr_t)s + pos) % 16) > 8) {\
        v1 = vec_ld(pos + a + 16, s);\
    }\
    vf = vec_perm(v0, src_v1, per);\
}
#define GET_VFD(a, b, f, vf0, vf1, per, vf, off) {\
    vf1 = vec_ld((a * 2 * filterSize) + (b * 2) + 16 + off, f);\
    vf  = vec_perm(vf0, vf1, per);\
}

#define FUNC(name) name ## _altivec
#include "swscale_ppc_template.c"
#undef FUNC

#endif /* HAVE_ALTIVEC && HAVE_BIGENDIAN */

av_cold void ff_sws_init_swscale_ppc(SwsContext *c)
{
#if HAVE_ALTIVEC
    enum AVPixelFormat dstFormat = c->dstFormat;

    if (!(av_get_cpu_flags() & AV_CPU_FLAG_ALTIVEC))
        return;

#if HAVE_BIGENDIAN
    if (c->srcBpc == 8 && c->dstBpc <= 14) {
        c->hyScale = c->hcScale = hScale_real_altivec;
    }
    if (!is16BPS(dstFormat) && !isNBPS(dstFormat) &&
        dstFormat != AV_PIX_FMT_NV12 && dstFormat != AV_PIX_FMT_NV21 &&
        dstFormat != AV_PIX_FMT_GRAYF32BE && dstFormat != AV_PIX_FMT_GRAYF32LE &&
        !c->needAlpha) {
        c->yuv2planeX = yuv2planeX_altivec;
    }
#endif

    /* The following list of supported dstFormat values should
     * match what's found in the body of ff_yuv2packedX_altivec() */
    if (!(c->flags & (SWS_BITEXACT | SWS_FULL_CHR_H_INT)) && !c->needAlpha) {
        switch (c->dstFormat) {
        case AV_PIX_FMT_ABGR:
            c->yuv2packedX = ff_yuv2abgr_X_altivec;
            break;
        case AV_PIX_FMT_BGRA:
            c->yuv2packedX = ff_yuv2bgra_X_altivec;
            break;
        case AV_PIX_FMT_ARGB:
            c->yuv2packedX = ff_yuv2argb_X_altivec;
            break;
        case AV_PIX_FMT_RGBA:
            c->yuv2packedX = ff_yuv2rgba_X_altivec;
            break;
        case AV_PIX_FMT_BGR24:
            c->yuv2packedX = ff_yuv2bgr24_X_altivec;
            break;
        case AV_PIX_FMT_RGB24:
            c->yuv2packedX = ff_yuv2rgb24_X_altivec;
            break;
        }
    }
#endif /* HAVE_ALTIVEC */

    ff_sws_init_swscale_vsx(c);
}