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#include "common.h"
#include <math.h>

static FLOAT csum_kernel_32(BLASLONG n, FLOAT *x) {
  FLOAT sum;

  __asm__("vzero   %%v24\n\t"
    "vzero   %%v25\n\t"
    "vzero   %%v26\n\t"
    "vzero   %%v27\n\t"
    "vzero   %%v28\n\t"
    "vzero   %%v29\n\t"
    "vzero   %%v30\n\t"
    "vzero   %%v31\n\t"
    "srlg  %[n],%[n],5\n\t"
    "xgr %%r1,%%r1\n\t"
    "0:\n\t"
    "pfd  1, 1024(%%r1,%[x])\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"
    "vfasb   %%v24,%%v24,%%v16\n\t"
    "vfasb   %%v25,%%v25,%%v17\n\t"
    "vfasb   %%v26,%%v26,%%v18\n\t"
    "vfasb   %%v27,%%v27,%%v19\n\t"
    "vfasb   %%v28,%%v28,%%v20\n\t"
    "vfasb   %%v29,%%v29,%%v21\n\t"
    "vfasb   %%v30,%%v30,%%v22\n\t"
    "vfasb   %%v31,%%v31,%%v23\n\t"
    "vl  %%v16, 128(%%r1,%[x])\n\t"
    "vl  %%v17, 144(%%r1,%[x])\n\t"
    "vl  %%v18, 160(%%r1,%[x])\n\t"
    "vl  %%v19, 176(%%r1,%[x])\n\t"
    "vl  %%v20, 192(%%r1,%[x])\n\t"
    "vl  %%v21, 208(%%r1,%[x])\n\t"
    "vl  %%v22, 224(%%r1,%[x])\n\t"
    "vl  %%v23, 240(%%r1,%[x])\n\t"
    "vfasb   %%v24,%%v24,%%v16\n\t"
    "vfasb   %%v25,%%v25,%%v17\n\t"
    "vfasb   %%v26,%%v26,%%v18\n\t"
    "vfasb   %%v27,%%v27,%%v19\n\t"
    "vfasb   %%v28,%%v28,%%v20\n\t"
    "vfasb   %%v29,%%v29,%%v21\n\t"
    "vfasb   %%v30,%%v30,%%v22\n\t"
    "vfasb   %%v31,%%v31,%%v23\n\t"
    "agfi  %%r1,256\n\t"
    "brctg %[n],0b\n\t"
    "vfasb   %%v24,%%v24,%%v25\n\t"
    "vfasb   %%v24,%%v24,%%v26\n\t"
    "vfasb   %%v24,%%v24,%%v27\n\t"
    "vfasb   %%v24,%%v24,%%v28\n\t"
    "vfasb   %%v24,%%v24,%%v29\n\t"
    "vfasb   %%v24,%%v24,%%v30\n\t"
    "vfasb   %%v24,%%v24,%%v31\n\t"
    "veslg   %%v25,%%v24,32\n\t"
    "vfasb   %%v24,%%v24,%%v25\n\t"
    "vrepf   %%v25,%%v24,2\n\t"
    "vfasb   %%v24,%%v24,%%v25\n\t"
    "vstef   %%v24,%[sum],0"
    : [sum] "=Q"(sum),[n] "+&r"(n)
    : "m"(*(const struct { FLOAT x[n * 2]; } *) x),[x] "a"(x)
    : "cc", "r1", "v16", "v17", "v18", "v19", "v20", "v21", "v22", "v23",
       "v24", "v25", "v26", "v27", "v28", "v29", "v30", "v31");

  return sum;
}

FLOAT CNAME(BLASLONG n, FLOAT *x, BLASLONG inc_x) {
  BLASLONG i = 0;
  BLASLONG ip = 0;
  FLOAT sumf = 0.0;
  BLASLONG n1;
  BLASLONG inc_x2;

  if (n <= 0 || inc_x <= 0)
    return (sumf);

  if (inc_x == 1) {

    n1 = n & -32;
    if (n1 > 0) {

      sumf = csum_kernel_32(n1, x);
      i = n1;
      ip = 2 * n1;
    }

    while (i < n) {
      sumf += x[ip] + x[ip + 1];
      i++;
      ip += 2;
    }

  } else {
    inc_x2 = 2 * inc_x;

    while (i < n) {
      sumf += x[ip] + x[ip + 1];
      ip += inc_x2;
      i++;
    }

  }
  return (sumf);
}
