OpenBLAS/kernel/zarch/dmax_z13.c

/***************************************************************************
Copyright (c) 2013-2019, The OpenBLAS Project
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#include "common.h"

static FLOAT dmax_kernel_32(BLASLONG n, FLOAT *x) {
  FLOAT max;

  __asm__("vl    %%v0,0(%[x])\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"
    "vfchdb  %%v24,%%v16,%%v17\n\t"
    "vfchdb  %%v25,%%v18,%%v19\n\t"
    "vfchdb  %%v26,%%v20,%%v21\n\t"
    "vfchdb  %%v27,%%v22,%%v23\n\t"
    "vsel    %%v24,%%v16,%%v17,%%v24\n\t"
    "vsel    %%v25,%%v18,%%v19,%%v25\n\t"
    "vsel    %%v26,%%v20,%%v21,%%v26\n\t"
    "vsel    %%v27,%%v22,%%v23,%%v27\n\t"
    "vfchdb  %%v28,%%v24,%%v25\n\t"
    "vfchdb  %%v29,%%v26,%%v27\n\t"
    "vsel    %%v28,%%v24,%%v25,%%v28\n\t"
    "vsel    %%v29,%%v26,%%v27,%%v29\n\t"
    "vfchdb  %%v30,%%v28,%%v29\n\t"
    "vsel    %%v30,%%v28,%%v29,%%v30\n\t"
    "vfchdb  %%v31,%%v30,%%v0\n\t"
    "vsel    %%v0,%%v30,%%v0,%%v31\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"
    "vfchdb  %%v24,%%v16,%%v17\n\t"
    "vfchdb  %%v25,%%v18,%%v19\n\t"
    "vfchdb  %%v26,%%v20,%%v21\n\t"
    "vfchdb  %%v27,%%v22,%%v23\n\t"
    "vsel    %%v24,%%v16,%%v17,%%v24\n\t"
    "vsel    %%v25,%%v18,%%v19,%%v25\n\t"
    "vsel    %%v26,%%v20,%%v21,%%v26\n\t"
    "vsel    %%v27,%%v22,%%v23,%%v27\n\t"
    "vfchdb  %%v28,%%v24,%%v25\n\t"
    "vfchdb  %%v29,%%v26,%%v27\n\t"
    "vsel    %%v28,%%v24,%%v25,%%v28\n\t"
    "vsel    %%v29,%%v26,%%v27,%%v29\n\t"
    "vfchdb  %%v30,%%v28,%%v29\n\t"
    "vsel    %%v30,%%v28,%%v29,%%v30\n\t"
    "vfchdb  %%v31,%%v30,%%v0\n\t"
    "vsel    %%v0,%%v30,%%v0,%%v31\n\t"
    "agfi    %%r1, 256\n\t"
    "brctg   %[n], 0b\n\t"
    "vrepg  %%v16,%%v0,1\n\t"
    "wfchdb %%v17,%%v0,%%v16\n\t"
    "vsel   %%v0,%%v0,%%v16,%%v17\n\t"
    "ldr    %[max],%%f0"
    : [max] "=f"(max),[n] "+&r"(n)
    : "m"(*(const FLOAT (*)[n]) x),[x] "a"(x)
    : "cc", "r1", "v0", "v16", "v17", "v18", "v19", "v20", "v21", "v22",
       "v23", "v24", "v25", "v26", "v27", "v28", "v29", "v30", "v31");

  return max;
}

FLOAT CNAME(BLASLONG n, FLOAT *x, BLASLONG inc_x) {
  BLASLONG i = 0;
  BLASLONG j = 0;
  FLOAT maxf = 0.0;

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

  if (inc_x == 1) {

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

      maxf = dmax_kernel_32(n1, x);

      i = n1;
    } else {
      maxf = x[0];
      i++;
    }

    while (i < n) {
      if (x[i] > maxf) {
        maxf = x[i];
      }
      i++;
    }
    return (maxf);

  } else {

    maxf = x[0];

    BLASLONG n1 = n & -4;
    while (j < n1) {

      if (x[i] > maxf) {
        maxf = x[i];
      }
      if (x[i + inc_x] > maxf) {
        maxf = x[i + inc_x];
      }
      if (x[i + 2 * inc_x] > maxf) {
        maxf = x[i + 2 * inc_x];
      }
      if (x[i + 3 * inc_x] > maxf) {
        maxf = x[i + 3 * inc_x];
      }

      i += inc_x * 4;

      j += 4;

    }

    while (j < n) {
      if (x[i] > maxf) {
        maxf = x[i];
      }
      i += inc_x;
      j++;
    }
    return (maxf);
  }
}