POWERPC_TBL_START_COUNT(altivec_gmc1_num, GMC1_PERF_COND);
POWERPC_PERF_START_COUNT(altivec_gmc1_num, GMC1_PERF_COND);
void gmc1_altivec(uint8_t *dst /* align 8 */, uint8_t *src /* align1 */, int stride, int h, int x16, int y16, int rounder){POWERPC_TBL_DECLARE(altivec_gmc1_num, GMC1_PERF_COND);#ifdef ALTIVEC_USE_REFERENCE_C_CODE    const int A=(16-x16)*(16-y16);    const int B=(   x16)*(16-y16);    const int C=(16-x16)*(   y16);    const int D=(   x16)*(   y16);    int i;POWERPC_TBL_START_COUNT(altivec_gmc1_num, GMC1_PERF_COND);        for(i=0; i<h; i++)    {        dst[0]= (A*src[0] + B*src[1] + C*src[stride+0] + D*src[stride+1] + rounder)>>8;        dst[1]= (A*src[1] + B*src[2] + C*src[stride+1] + D*src[stride+2] + rounder)>>8;        dst[2]= (A*src[2] + B*src[3] + C*src[stride+2] + D*src[stride+3] + rounder)>>8;        dst[3]= (A*src[3] + B*src[4] + C*src[stride+3] + D*src[stride+4] + rounder)>>8;        dst[4]= (A*src[4] + B*src[5] + C*src[stride+4] + D*src[stride+5] + rounder)>>8;        dst[5]= (A*src[5] + B*src[6] + C*src[stride+5] + D*src[stride+6] + rounder)>>8;        dst[6]= (A*src[6] + B*src[7] + C*src[stride+6] + D*src[stride+7] + rounder)>>8;        dst[7]= (A*src[7] + B*src[8] + C*src[stride+7] + D*src[stride+8] + rounder)>>8;        dst+= stride;        src+= stride;    }POWERPC_TBL_STOP_COUNT(altivec_gmc1_num, GMC1_PERF_COND);#else /* ALTIVEC_USE_REFERENCE_C_CODE */    const unsigned short __attribute__ ((aligned(16))) rounder_a[8] =      {rounder, rounder, rounder, rounder,       rounder, rounder, rounder, rounder};    const unsigned short __attribute__ ((aligned(16))) 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_TBL_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_TBL_STOP_COUNT(altivec_gmc1_num, GMC1_PERF_COND);#endif /* ALTIVEC_USE_REFERENCE_C_CODE */}