vs16(x0) = vec_add(vs16(b00), vs16(b70)); vs16(x7) = vec_sub(vs16(b00), vs16(b70)); vs16(x1) = vec_add(vs16(b10), vs16(b60)); vs16(x6) = vec_sub(vs16(b10), vs16(b60)); vs16(x2) = vec_add(vs16(b20), vs16(b50)); vs16(x5) = vec_sub(vs16(b20), vs16(b50)); vs16(x3) = vec_add(vs16(b30), vs16(b40)); vs16(x4) = vec_sub(vs16(b30), vs16(b40));  vs16(b70) = vec_add(vs16(x0), vs16(x3)); vs16(b10) = vec_add(vs16(x1), vs16(x2));  vs16(b00) = vec_add(vs16(b70), vs16(b10)); vs16(b40) = vec_sub(vs16(b70), vs16(b10));
x0 = ((vector float)vec_add(vs16(b00), vs16(b70))); x7 = ((vector float)vec_sub(vs16(b00), vs16(b70))); x1 = ((vector float)vec_add(vs16(b10), vs16(b60))); x6 = ((vector float)vec_sub(vs16(b10), vs16(b60))); x2 = ((vector float)vec_add(vs16(b20), vs16(b50))); x5 = ((vector float)vec_sub(vs16(b20), vs16(b50))); x3 = ((vector float)vec_add(vs16(b30), vs16(b40))); x4 = ((vector float)vec_sub(vs16(b30), vs16(b40)));  b70 = ((vector float)vec_add(vs16(x0), vs16(x3))); b10 = ((vector float)vec_add(vs16(x1), vs16(x2)));  b00 = ((vector float)vec_add(vs16(b70), vs16(b10))); b40 = ((vector float)vec_sub(vs16(b70), vs16(b10)));
void fdct_altivec(int16_t *block){POWERPC_PERF_DECLARE(altivec_fdct, 1);#ifdef ALTIVEC_USE_REFERENCE_C_CODEPOWERPC_PERF_START_COUNT(altivec_fdct, 1);    void ff_jpeg_fdct_islow(int16_t *block);    ff_jpeg_fdct_islow(block);POWERPC_PERF_STOP_COUNT(altivec_fdct, 1);#else /* ALTIVEC_USE_REFERENCE_C_CODE */    vector signed short *bp;    vector float *cp;    vector float b00, b10, b20, b30, b40, b50, b60, b70;    vector float b01, b11, b21, b31, b41, b51, b61, b71;    vector float mzero, cnst, cnsts0, cnsts1, cnsts2;    vector float x0, x1, x2, x3, x4, x5, x6, x7, x8;    POWERPC_PERF_START_COUNT(altivec_fdct, 1);    /* setup constants {{{ */    /* mzero = -0.0 */    vu32(mzero) = vec_splat_u32(-1);    vu32(mzero) = vec_sl(vu32(mzero), vu32(mzero));    cp = fdctconsts;    cnsts0 = vec_ld(0, cp); cp++;    cnsts1 = vec_ld(0, cp); cp++;    cnsts2 = vec_ld(0, cp);    /* }}} */    /* 8x8 matrix transpose (vector short[8]) {{{ */#define MERGE_S16(hl,a,b) vec_merge##hl(vs16(a), vs16(b))    bp = (vector signed short*)block;    vs16(b00) = vec_ld(0,    bp);    vs16(b40) = vec_ld(16*4, bp);    vs16(b01) = MERGE_S16(h, b00, b40);    vs16(b11) = MERGE_S16(l, b00, b40);    bp++;    vs16(b10) = vec_ld(0,    bp);    vs16(b50) = vec_ld(16*4, bp);    vs16(b21) = MERGE_S16(h, b10, b50);    vs16(b31) = MERGE_S16(l, b10, b50);    bp++;    vs16(b20) = vec_ld(0,    bp);    vs16(b60) = vec_ld(16*4, bp);    vs16(b41) = MERGE_S16(h, b20, b60);    vs16(b51) = MERGE_S16(l, b20, b60);    bp++;    vs16(b30) = vec_ld(0,    bp);    vs16(b70) = vec_ld(16*4, bp);    vs16(b61) = MERGE_S16(h, b30, b70);    vs16(b71) = MERGE_S16(l, b30, b70);    vs16(x0) = MERGE_S16(h, b01, b41);    vs16(x1) = MERGE_S16(l, b01, b41);    vs16(x2) = MERGE_S16(h, b11, b51);    vs16(x3) = MERGE_S16(l, b11, b51);    vs16(x4) = MERGE_S16(h, b21, b61);    vs16(x5) = MERGE_S16(l, b21, b61);    vs16(x6) = MERGE_S16(h, b31, b71);    vs16(x7) = MERGE_S16(l, b31, b71);    vs16(b00) = MERGE_S16(h, x0, x4);    vs16(b10) = MERGE_S16(l, x0, x4);    vs16(b20) = MERGE_S16(h, x1, x5);    vs16(b30) = MERGE_S16(l, x1, x5);    vs16(b40) = MERGE_S16(h, x2, x6);    vs16(b50) = MERGE_S16(l, x2, x6);    vs16(b60) = MERGE_S16(h, x3, x7);    vs16(b70) = MERGE_S16(l, x3, x7);#undef MERGE_S16    /* }}} *//* Some of the initial calculations can be done as vector short before * conversion to vector float.  The following code section takes advantage * of this. */#if 1    /* fdct rows {{{ */    vs16(x0) = vec_add(vs16(b00), vs16(b70));    vs16(x7) = vec_sub(vs16(b00), vs16(b70));    vs16(x1) = vec_add(vs16(b10), vs16(b60));    vs16(x6) = vec_sub(vs16(b10), vs16(b60));    vs16(x2) = vec_add(vs16(b20), vs16(b50));    vs16(x5) = vec_sub(vs16(b20), vs16(b50));    vs16(x3) = vec_add(vs16(b30), vs16(b40));    vs16(x4) = vec_sub(vs16(b30), vs16(b40));    vs16(b70) = vec_add(vs16(x0), vs16(x3));    vs16(b10) = vec_add(vs16(x1), vs16(x2));    vs16(b00) = vec_add(vs16(b70), vs16(b10));    vs16(b40) = vec_sub(vs16(b70), vs16(b10));#define CTF0(n) \    vs32(b##n##1) = vec_unpackl(vs16(b##n##0)); \    vs32(b##n##0) = vec_unpackh(vs16(b##n##0)); \    b##n##1 = vec_ctf(vs32(b##n##1), 0); \    b##n##0 = vec_ctf(vs32(b##n##0), 0);    CTF0(0);    CTF0(4);    vs16(b20) = vec_sub(vs16(x0), vs16(x3));    vs16(b60) = vec_sub(vs16(x1), vs16(x2));    CTF0(2);    CTF0(6);#undef CTF0    x0 = vec_add(b60, b20);    x1 = vec_add(b61, b21);    cnst = LD_W2;    x0 = vec_madd(cnst, x0, mzero);    x1 = vec_madd(cnst, x1, mzero);    cnst = LD_W1;    b20 = vec_madd(cnst, b20, x0);    b21 = vec_madd(cnst, b21, x1);    cnst = LD_W0;    b60 = vec_madd(cnst, b60, x0);    b61 = vec_madd(cnst, b61, x1);#define CTFX(x,b) \    vs32(b##0) = vec_unpackh(vs16(x)); \    vs32(b##1) = vec_unpackl(vs16(x)); \    b##0 = vec_ctf(vs32(b##0), 0); \    b##1 = vec_ctf(vs32(b##1), 0); \    CTFX(x4, b7);    CTFX(x5, b5);    CTFX(x6, b3);    CTFX(x7, b1);#undef CTFX    x0 = vec_add(b70, b10);    x1 = vec_add(b50, b30);    x2 = vec_add(b70, b30);    x3 = vec_add(b50, b10);    x8 = vec_add(x2, x3);    cnst = LD_W3;    x8 = vec_madd(cnst, x8, mzero);    cnst = LD_W8;    x0 = vec_madd(cnst, x0, mzero);    cnst = LD_W9;    x1 = vec_madd(cnst, x1, mzero);    cnst = LD_WA;    x2 = vec_madd(cnst, x2, x8);    cnst = LD_WB;    x3 = vec_madd(cnst, x3, x8);    cnst = LD_W4;    b70 = vec_madd(cnst, b70, x0);    cnst = LD_W5;    b50 = vec_madd(cnst, b50, x1);    cnst = LD_W6;    b30 = vec_madd(cnst, b30, x1);    cnst = LD_W7;    b10 = vec_madd(cnst, b10, x0);    b70 = vec_add(b70, x2);    b50 = vec_add(b50, x3);    b30 = vec_add(b30, x2);    b10 = vec_add(b10, x3);    x0 = vec_add(b71, b11);    x1 = vec_add(b51, b31);    x2 = vec_add(b71, b31);    x3 = vec_add(b51, b11);    x8 = vec_add(x2, x3);    cnst = LD_W3;    x8 = vec_madd(cnst, x8, mzero);    cnst = LD_W8;    x0 = vec_madd(cnst, x0, mzero);    cnst = LD_W9;    x1 = vec_madd(cnst, x1, mzero);    cnst = LD_WA;    x2 = vec_madd(cnst, x2, x8);    cnst = LD_WB;    x3 = vec_madd(cnst, x3, x8);    cnst = LD_W4;    b71 = vec_madd(cnst, b71, x0);    cnst = LD_W5;    b51 = vec_madd(cnst, b51, x1);    cnst = LD_W6;    b31 = vec_madd(cnst, b31, x1);    cnst = LD_W7;    b11 = vec_madd(cnst, b11, x0);    b71 = vec_add(b71, x2);    b51 = vec_add(b51, x3);    b31 = vec_add(b31, x2);    b11 = vec_add(b11, x3);    /* }}} */#else    /* convert to float {{{ */#define CTF(n) \    vs32(b##n##1) = vec_unpackl(vs16(b##n##0)); \    vs32(b##n##0) = vec_unpackh(vs16(b##n##0)); \    b##n##1 = vec_ctf(vs32(b##n##1), 0); \    b##n##0 = vec_ctf(vs32(b##n##0), 0); \    CTF(0);    CTF(1);    CTF(2);    CTF(3);    CTF(4);    CTF(5);    CTF(6);    CTF(7);#undef CTF    /* }}} */    FDCTROW(b00, b10, b20, b30, b40, b50, b60, b70);    FDCTROW(b01, b11, b21, b31, b41, b51, b61, b71);#endif    /* 8x8 matrix transpose (vector float[8][2]) {{{ */    x0 = vec_mergel(b00, b20);    x1 = vec_mergeh(b00, b20);    x2 = vec_mergel(b10, b30);    x3 = vec_mergeh(b10, b30);    b00 = vec_mergeh(x1, x3);    b10 = vec_mergel(x1, x3);    b20 = vec_mergeh(x0, x2);    b30 = vec_mergel(x0, x2);    x4 = vec_mergel(b41, b61);    x5 = vec_mergeh(b41, b61);    x6 = vec_mergel(b51, b71);    x7 = vec_mergeh(b51, b71);    b41 = vec_mergeh(x5, x7);    b51 = vec_mergel(x5, x7);    b61 = vec_mergeh(x4, x6);    b71 = vec_mergel(x4, x6);    x0 = vec_mergel(b01, b21);    x1 = vec_mergeh(b01, b21);    x2 = vec_mergel(b11, b31);    x3 = vec_mergeh(b11, b31);    x4 = vec_mergel(b40, b60);    x5 = vec_mergeh(b40, b60);    x6 = vec_mergel(b50, b70);    x7 = vec_mergeh(b50, b70);    b40 = vec_mergeh(x1, x3);    b50 = vec_mergel(x1, x3);    b60 = vec_mergeh(x0, x2);    b70 = vec_mergel(x0, x2);    b01 = vec_mergeh(x5, x7);    b11 = vec_mergel(x5, x7);    b21 = vec_mergeh(x4, x6);    b31 = vec_mergel(x4, x6);    /* }}} */    FDCTCOL(b00, b10, b20, b30, b40, b50, b60, b70);    FDCTCOL(b01, b11, b21, b31, b41, b51, b61, b71);    /* round, convert back to short {{{ */#define CTS(n) \    b##n##0 = vec_round(b##n##0); \    b##n##1 = vec_round(b##n##1); \    vs32(b##n##0) = vec_cts(b##n##0, 0); \    vs32(b##n##1) = vec_cts(b##n##1, 0); \    vs16(b##n##0) = vec_pack(vs32(b##n##0), vs32(b##n##1)); \    vec_st(vs16(b##n##0), 0, bp);    bp = (vector signed short*)block;    CTS(0); bp++;    CTS(1); bp++;    CTS(2); bp++;    CTS(3); bp++;    CTS(4); bp++;    CTS(5); bp++;    CTS(6); bp++;    CTS(7);#undef CTS    /* }}} */POWERPC_PERF_STOP_COUNT(altivec_fdct, 1);#endif /* ALTIVEC_USE_REFERENCE_C_CODE */}