OpenBLAS/kernel/zarch/idamin.c

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

#define ABS fabs

static BLASLONG idamin_kernel_32(BLASLONG n, FLOAT *x, FLOAT *amin) {
  BLASLONG iamin;

  __asm__("vl     %%v0,0(%[x])\n\t"
    "vflpdb %%v0,%%v0\n\t"
    "vleig  %%v1,0,0\n\t"
    "vleig  %%v1,1,1\n\t"
    "vrepig %%v2,16\n\t"
    "vzero  %%v3\n\t"
    "vleig  %%v24,0,0\n\t"
    "vleig  %%v24,1,1\n\t"
    "vleig  %%v25,2,0\n\t"
    "vleig  %%v25,3,1\n\t"
    "vleig  %%v26,4,0\n\t"
    "vleig  %%v26,5,1\n\t"
    "vleig  %%v27,6,0\n\t"
    "vleig  %%v27,7,1\n\t"
    "vleig  %%v28,8,0\n\t"
    "vleig  %%v28,9,1\n\t"
    "vleig  %%v29,10,0\n\t"
    "vleig  %%v29,11,1\n\t"
    "vleig  %%v30,12,0\n\t"
    "vleig  %%v30,13,1\n\t"
    "vleig  %%v31,14,0\n\t"
    "vleig  %%v31,15,1\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"
    "vflpdb  %%v16, %%v16\n\t"
    "vflpdb  %%v17, %%v17\n\t"
    "vflpdb  %%v18, %%v18\n\t"
    "vflpdb  %%v19, %%v19\n\t"
    "vflpdb  %%v20, %%v20\n\t"
    "vflpdb  %%v21, %%v21\n\t"
    "vflpdb  %%v22, %%v22\n\t"
    "vflpdb  %%v23, %%v23\n\t"
    "vfchedb  %%v4,%%v17,%%v16\n\t"
    "vfchedb  %%v5,%%v19,%%v18\n\t"
    "vfchedb  %%v6,%%v21,%%v20\n\t"
    "vfchedb  %%v7,%%v23,%%v22\n\t"
    "vsel    %%v16,%%v16,%%v17,%%v4\n\t"
    "vsel    %%v4,%%v24,%%v25,%%v4\n\t"
    "vsel    %%v17,%%v18,%%v19,%%v5\n\t"
    "vsel    %%v5,%%v26,%%v27,%%v5\n\t"
    "vsel    %%v18,%%v20,%%v21,%%v6\n\t"
    "vsel    %%v6,%%v28,%%v29,%%v6\n\t"
    "vsel    %%v19,%%v22,%%v23,%%v7\n\t"
    "vsel    %%v7,%%v30,%%v31,%%v7\n\t"
    "vfchedb  %%v20,%%v17,%%v16\n\t"
    "vfchedb  %%v21,%%v19,%%v18\n\t"
    "vsel    %%v16,%%v16,%%v17,%%v20\n\t"
    "vsel    %%v4,%%v4,%%v5,%%v20\n\t"
    "vsel    %%v17,%%v18,%%v19,%%v21\n\t"
    "vsel    %%v5,%%v6,%%v7,%%v21\n\t"
    "vfchedb  %%v18,%%v17,%%v16\n\t"
    "vsel    %%v16,%%v16,%%v17,%%v18\n\t"
    "vsel    %%v4,%%v4,%%v5,%%v18\n\t"
    "vag     %%v4,%%v4,%%v3\n\t"
    "vfchedb  %%v5,%%v16,%%v0\n\t"
    "vsel    %%v0,%%v0,%%v16,%%v5\n\t"
    "vsel    %%v1,%%v1,%%v4,%%v5\n\t"
    "vag     %%v3,%%v3,%%v2\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"
    "vflpdb  %%v16, %%v16\n\t"
    "vflpdb  %%v17, %%v17\n\t"
    "vflpdb  %%v18, %%v18\n\t"
    "vflpdb  %%v19, %%v19\n\t"
    "vflpdb  %%v20, %%v20\n\t"
    "vflpdb  %%v21, %%v21\n\t"
    "vflpdb  %%v22, %%v22\n\t"
    "vflpdb  %%v23, %%v23\n\t"
    "vfchedb  %%v4,%%v17,%%v16\n\t"
    "vfchedb  %%v5,%%v19,%%v18\n\t"
    "vfchedb  %%v6,%%v21,%%v20\n\t"
    "vfchedb  %%v7,%%v23,%%v22\n\t"
    "vsel    %%v16,%%v16,%%v17,%%v4\n\t"
    "vsel    %%v4,%%v24,%%v25,%%v4\n\t"
    "vsel    %%v17,%%v18,%%v19,%%v5\n\t"
    "vsel    %%v5,%%v26,%%v27,%%v5\n\t"
    "vsel    %%v18,%%v20,%%v21,%%v6\n\t"
    "vsel    %%v6,%%v28,%%v29,%%v6\n\t"
    "vsel    %%v19,%%v22,%%v23,%%v7\n\t"
    "vsel    %%v7,%%v30,%%v31,%%v7\n\t"
    "vfchedb  %%v20,%%v17,%%v16\n\t"
    "vfchedb  %%v21,%%v19,%%v18\n\t"
    "vsel    %%v16,%%v16,%%v17,%%v20\n\t"
    "vsel    %%v4,%%v4,%%v5,%%v20\n\t"
    "vsel    %%v17,%%v18,%%v19,%%v21\n\t"
    "vsel    %%v5,%%v6,%%v7,%%v21\n\t"
    "vfchedb  %%v18,%%v17,%%v16\n\t"
    "vsel    %%v16,%%v16,%%v17,%%v18\n\t"
    "vsel    %%v4,%%v4,%%v5,%%v18\n\t"
    "vag     %%v4,%%v4,%%v3\n\t"
    "vfchedb  %%v5,%%v16,%%v0\n\t"
    "vsel    %%v0,%%v0,%%v16,%%v5\n\t"
    "vsel    %%v1,%%v1,%%v4,%%v5\n\t"
    "vag     %%v3,%%v3,%%v2\n\t"
    "agfi    %%r1, 256\n\t"
    "brctg   %[n], 0b\n\t"
    "vrepg  %%v2,%%v0,1\n\t"
    "vrepg  %%v3,%%v1,1\n\t"
    "wfcdb  %%v2,%%v0\n\t"
    "jne 1f\n\t"
    "vsteg  %%v0,%[amin],0\n\t"
    "vmnlg  %%v0,%%v1,%%v3\n\t"
    "vlgvg  %[iamin],%%v0,0\n\t"
    "j 2f\n\t"
    "1:\n\t"
    "wfchdb %%v4,%%v0,%%v2\n\t"
    "vsel   %%v1,%%v3,%%v1,%%v4\n\t"
    "vsel   %%v0,%%v2,%%v0,%%v4\n\t"
    "std    %%f0,%[amin]\n\t"
    "vlgvg  %[iamin],%%v1,0\n\t"
    "2:\n\t"
    "nop 0"
    : [iamin] "=r"(iamin),[amin] "=Q"(*amin),[n] "+&r"(n)
    : "m"(*(const FLOAT (*)[n]) x),[x] "a"(x)
    : "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 iamin;
}

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

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

  if (inc_x == 1) {

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

      min = idamin_kernel_32(n1, x, &minf);

      i = n1;
    } else {
      minf = ABS(x[0]);
      i++;
    }

    while (i < n) {
      if (ABS(x[i]) < minf) {
        min = i;
        minf = ABS(x[i]);
      }
      i++;
    }
    return (min + 1);

  } else {

    min = 0;
    minf = ABS(x[0]);

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

      if (ABS(x[i]) < minf) {
        min = j;
        minf = ABS(x[i]);
      }
      if (ABS(x[i + inc_x]) < minf) {
        min = j + 1;
        minf = ABS(x[i + inc_x]);
      }
      if (ABS(x[i + 2 * inc_x]) < minf) {
        min = j + 2;
        minf = ABS(x[i + 2 * inc_x]);
      }
      if (ABS(x[i + 3 * inc_x]) < minf) {
        min = j + 3;
        minf = ABS(x[i + 3 * inc_x]);
      }

      i += inc_x * 4;

      j += 4;

    }

    while (j < n) {
      if (ABS(x[i]) < minf) {
        min = j;
        minf = ABS(x[i]);
      }
      i += inc_x;
      j++;
    }
    return (min + 1);
  }
}