OpenBLAS/interface/lapack/laed3.c

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

#if defined(DOUBLE)
#define ERROR_NAME "DLAED3"
#else
#define ERROR_NAME "SLAED3"
#endif

/* ===================================================================== */
int NAME(blasint *k, blasint *n, blasint *n1, FLOAT *d, 
        FLOAT *q, blasint *ldq, FLOAT *rho, FLOAT *dlamda,
        FLOAT *q2, blasint *indx, blasint *ctot, FLOAT *w, 
        FLOAT *s, blasint *Info)
{
  blasint kval, nval, qdim, info;

  qdim = *ldq;
  kval = *k;
  nval = *n;

/*   Test the input parameters. */
  info = 0;
  if (kval < 0) {
    info = 1;
  } else if (nval < kval) {
    info = 2;
  } else if (qdim < nval || qdim < 1) {
    info = 6;
  }
  if (info) {
    BLASFUNC(xerbla)(ERROR_NAME, &info, sizeof(ERROR_NAME) - 1);
    *Info = - info;
    return 0;
  }

/*   Quick return if possible */

  *Info = 0;
  if (kval == 0) return 0;

#ifdef SMP
  int nthreads = num_cpu_avail(4);

  if (nthreads == 1) {
#endif
    LAED3_SINGLE(k, n, n1, d, q, ldq, rho, dlamda, q2, indx, ctot, w, s, Info);
#ifdef SMP
  } else {
    LAED3_PARALLEL(k, n, n1, d, q, ldq, rho, dlamda, q2, indx, ctot, w, s, Info);
  }
#endif

  return 0;
}