/* * GMC (Global Motion Compensation) * AltiVec-enabled * Copyright (c) 2003 Romain Dolbeau <romain@dolbeau.org> * * 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 "libavcodec/dsputil.h"#include "gcc_fixes.h"#include "dsputil_ppc.h"#include "util_altivec.h"/*  altivec-enhanced gmc1. ATM this code assume stride is a multiple of 8,  to preserve proper dst alignment.*/#define GMC1_PERF_COND (h==8)void gmc1_altivec(uint8_t *dst /* align 8 */, uint8_t *src /* align1 */, int stride, int h, int x16, int y16, int rounder){POWERPC_PERF_DECLARE(altivec_gmc1_num, GMC1_PERF_COND);    const DECLARE_ALIGNED_16(unsigned short, rounder_a[8]) =      {rounder, rounder, rounder, rounder,       rounder, rounder, rounder, rounder};    const DECLARE_ALIGNED_16(unsigned short, ABCD[8]) =      {        (16-x16)*(16-y16), /* A */        (   x16)*(16-y16), /* B */        (16-x16)*(   y16), /* C */        (   x16)*(   y16), /* D */        0, 0, 0, 0         /* padding */      };    register const vector unsigned char vczero = (const vector unsigned char)vec_splat_u8(0);    register const vector unsigned short vcsr8 = (const vector unsigned short)vec_splat_u16(8);    register vector unsigned char dstv, dstv2, src_0, src_1, srcvA, srcvB, srcvC, srcvD;    register vector unsigned short Av, Bv, Cv, Dv, rounderV, tempA, tempB, tempC, tempD;    int i;    unsigned long dst_odd = (unsigned long)dst & 0x0000000F;    unsigned long src_really_odd = (unsigned long)src & 0x0000000F;POWERPC_PERF_START_COUNT(altivec_gmc1_num, GMC1_PERF_COND);    tempA = vec_ld(0, (unsigned short*)ABCD);    Av = vec_splat(tempA, 0);    Bv = vec_splat(tempA, 1);    Cv = vec_splat(tempA, 2);    Dv = vec_splat(tempA, 3);    rounderV = vec_ld(0, (unsigned short*)rounder_a);    // we'll be able to pick-up our 9 char elements    // at src from those 32 bytes    // we load the first batch here, as inside the loop    // we can re-use 'src+stride' from one iteration    // as the 'src' of the next.    src_0 = vec_ld(0, src);    src_1 = vec_ld(16, src);    srcvA = vec_perm(src_0, src_1, vec_lvsl(0, src));    if (src_really_odd != 0x0000000F)    { // if src & 0xF == 0xF, then (src+1) is properly aligned on the second vector.      srcvB = vec_perm(src_0, src_1, vec_lvsl(1, src));    }    else    {      srcvB = src_1;    }    srcvA = vec_mergeh(vczero, srcvA);    srcvB = vec_mergeh(vczero, srcvB);    for(i=0; i<h; i++)    {      dst_odd = (unsigned long)dst & 0x0000000F;      src_really_odd = (((unsigned long)src) + stride) & 0x0000000F;      dstv = vec_ld(0, dst);      // we we'll be able to pick-up our 9 char elements      // at src + stride from those 32 bytes      // then reuse the resulting 2 vectors srvcC and srcvD      // as the next srcvA and srcvB      src_0 = vec_ld(stride + 0, src);      src_1 = vec_ld(stride + 16, src);      srcvC = vec_perm(src_0, src_1, vec_lvsl(stride + 0, src));      if (src_really_odd != 0x0000000F)      { // if src & 0xF == 0xF, then (src+1) is properly aligned on the second vector.        srcvD = vec_perm(src_0, src_1, vec_lvsl(stride + 1, src));      }      else      {        srcvD = src_1;      }      srcvC = vec_mergeh(vczero, srcvC);      srcvD = vec_mergeh(vczero, srcvD);      // OK, now we (finally) do the math :-)      // those four instructions replaces 32 int muls & 32 int adds.      // isn't AltiVec nice ?      tempA = vec_mladd((vector unsigned short)srcvA, Av, rounderV);      tempB = vec_mladd((vector unsigned short)srcvB, Bv, tempA);      tempC = vec_mladd((vector unsigned short)srcvC, Cv, tempB);      tempD = vec_mladd((vector unsigned short)srcvD, Dv, tempC);      srcvA = srcvC;      srcvB = srcvD;      tempD = vec_sr(tempD, vcsr8);      dstv2 = vec_pack(tempD, (vector unsigned short)vczero);      if (dst_odd)      {        dstv2 = vec_perm(dstv, dstv2, vcprm(0,1,s0,s1));      }      else      {        dstv2 = vec_perm(dstv, dstv2, vcprm(s0,s1,2,3));      }      vec_st(dstv2, 0, dst);      dst += stride;      src += stride;    }POWERPC_PERF_STOP_COUNT(altivec_gmc1_num, GMC1_PERF_COND);}