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#include "common.h"

static FLOAT ddot_kernel_16(BLASLONG n, FLOAT *x, FLOAT *y) {
  FLOAT dot;

  __asm__("vzero %%v0\n\t"
    "vzero %%v1\n\t"
    "vzero %%v2\n\t"
    "vzero %%v3\n\t"
    "vzero %%v4\n\t"
    "vzero %%v5\n\t"
    "vzero %%v6\n\t"
    "vzero %%v7\n\t"
    "srlg  %[n],%[n],4\n\t"
    "xgr   %%r1,%%r1\n\t"
    "0:\n\t"
    "pfd 1,1024(%%r1,%[x])\n\t"
    "pfd 1,1024(%%r1,%[y])\n\t"
    "vl  %%v16,0(%%r1,%[x])\n\t"
    "vl  %%v17,16(%%r1,%[x])\n\t"
    "vl  %%v18,32(%%r1,%[x])\n\t"
    "vl  %%v19,48(%%r1,%[x])\n\t"
    "vl  %%v20,64(%%r1,%[x])\n\t"
    "vl  %%v21,80(%%r1,%[x])\n\t"
    "vl  %%v22,96(%%r1,%[x])\n\t"
    "vl  %%v23,112(%%r1,%[x])\n\t"
    "vl  %%v24,0(%%r1,%[y])\n\t"
    "vl  %%v25,16(%%r1,%[y])\n\t"
    "vl  %%v26,32(%%r1,%[y])\n\t"
    "vl  %%v27,48(%%r1,%[y])\n\t"
    "vl  %%v28,64(%%r1,%[y])\n\t"
    "vl  %%v29,80(%%r1,%[y])\n\t"
    "vl  %%v30,96(%%r1,%[y])\n\t"
    "vl  %%v31,112(%%r1,%[y])\n\t"
    "vfmadb   %%v0,%%v16,%%v24,%%v0\n\t"
    "vfmadb   %%v1,%%v17,%%v25,%%v1\n\t"
    "vfmadb   %%v2,%%v18,%%v26,%%v2\n\t"
    "vfmadb   %%v3,%%v19,%%v27,%%v3\n\t"
    "vfmadb   %%v4,%%v20,%%v28,%%v4\n\t"
    "vfmadb   %%v5,%%v21,%%v29,%%v5\n\t"
    "vfmadb   %%v6,%%v22,%%v30,%%v6\n\t"
    "vfmadb   %%v7,%%v23,%%v31,%%v7\n\t"
    "agfi   %%r1,128\n\t"
    "brctg  %[n],0b\n\t"
    "vfadb   %%v0,%%v0,%%v1\n\t"
    "vfadb   %%v0,%%v0,%%v2\n\t"
    "vfadb   %%v0,%%v0,%%v3\n\t"
    "vfadb   %%v0,%%v0,%%v4\n\t"
    "vfadb   %%v0,%%v0,%%v5\n\t"
    "vfadb   %%v0,%%v0,%%v6\n\t"
    "vfadb   %%v0,%%v0,%%v7\n\t"
    "vrepg  %%v1,%%v0,1\n\t"
    "adbr   %%f0,%%f1\n\t"
    "ldr    %[dot],%%f0"
    : [dot] "=f"(dot),[n] "+&r"(n)
    : "m"(*(const struct { FLOAT x[n]; } *) x),[x] "a"(x),
       "m"(*(const struct { FLOAT x[n]; } *) y),[y] "a"(y)
    : "cc", "r1", "v0", "v1", "v2", "v3", "v4", "v5", "v6", "v7", "v16",
       "v17", "v18", "v19", "v20", "v21", "v22", "v23", "v24", "v25", "v26",
       "v27", "v28", "v29", "v30", "v31");

  return dot;
}

FLOAT CNAME(BLASLONG n, FLOAT *x, BLASLONG inc_x, FLOAT *y, BLASLONG inc_y) {
  BLASLONG i = 0;
  BLASLONG ix = 0, iy = 0;

  FLOAT dot = 0.0;

  if (n <= 0)
    return (dot);

  if ((inc_x == 1) && (inc_y == 1)) {

    BLASLONG n1 = n & -16;

    if (n1)
      dot = ddot_kernel_16(n1, x, y);

    i = n1;
    while (i < n) {

      dot += y[i] * x[i];
      i++;

    }
    return (dot);

  }

  FLOAT temp1 = 0.0;
  FLOAT temp2 = 0.0;

  BLASLONG n1 = n & -4;

  while (i < n1) {

    FLOAT m1 = y[iy] * x[ix];
    FLOAT m2 = y[iy + inc_y] * x[ix + inc_x];

    FLOAT m3 = y[iy + 2 * inc_y] * x[ix + 2 * inc_x];
    FLOAT m4 = y[iy + 3 * inc_y] * x[ix + 3 * inc_x];

    ix += inc_x * 4;
    iy += inc_y * 4;

    temp1 += m1 + m3;
    temp2 += m2 + m4;

    i += 4;

  }

  while (i < n) {

    temp1 += y[iy] * x[ix];
    ix += inc_x;
    iy += inc_y;
    i++;

  }
  dot = temp1 + temp2;
  return (dot);

}
