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|
#include "blaswrap.h"
#include "f2c.h"
integer ilaenv_(integer *ispec, char *name__, char *opts, integer *n1,
integer *n2, integer *n3, integer *n4, ftnlen name_len, ftnlen
opts_len)
{
/* -- LAPACK auxiliary routine (version 3.0) --
Univ. of Tennessee, Univ. of California Berkeley, NAG Ltd.,
Courant Institute, Argonne National Lab, and Rice University
June 30, 1999
Purpose
=======
ILAENV is called from the LAPACK routines to choose problem-dependent
parameters for the local environment. See ISPEC for a description of
the parameters.
This version provides a set of parameters which should give good,
but not optimal, performance on many of the currently available
computers. Users are encouraged to modify this subroutine to set
the tuning parameters for their particular machine using the option
and problem size information in the arguments.
This routine will not function correctly if it is converted to all
lower case. Converting it to all upper case is allowed.
Arguments
=========
ISPEC (input) INTEGER
Specifies the parameter to be returned as the value of
ILAENV.
= 1: the optimal blocksize; if this value is 1, an unblocked
algorithm will give the best performance.
= 2: the minimum block size for which the block routine
should be used; if the usable block size is less than
this value, an unblocked routine should be used.
= 3: the crossover point (in a block routine, for N less
than this value, an unblocked routine should be used)
= 4: the number of shifts, used in the nonsymmetric
eigenvalue routines
= 5: the minimum column dimension for blocking to be used;
rectangular blocks must have dimension at least k by m,
where k is given by ILAENV(2,...) and m by ILAENV(5,...)
= 6: the crossover point for the SVD (when reducing an m by n
matrix to bidiagonal form, if max(m,n)/min(m,n) exceeds
this value, a QR factorization is used first to reduce
the matrix to a triangular form.)
= 7: the number of processors
= 8: the crossover point for the multishift QR and QZ methods
for nonsymmetric eigenvalue problems.
= 9: maximum size of the subproblems at the bottom of the
computation tree in the divide-and-conquer algorithm
(used by xGELSD and xGESDD)
=10: ieee NaN arithmetic can be trusted not to trap
=11: infinity arithmetic can be trusted not to trap
NAME (input) CHARACTER*(*)
The name of the calling subroutine, in either upper case or
lower case.
OPTS (input) CHARACTER*(*)
The character options to the subroutine NAME, concatenated
into a single character string. For example, UPLO = 'U',
TRANS = 'T', and DIAG = 'N' for a triangular routine would
be specified as OPTS = 'UTN'.
N1 (input) INTEGER
N2 (input) INTEGER
N3 (input) INTEGER
N4 (input) INTEGER
Problem dimensions for the subroutine NAME; these may not all
be required.
(ILAENV) (output) INTEGER
>= 0: the value of the parameter specified by ISPEC
< 0: if ILAENV = -k, the k-th argument had an illegal value.
Further Details
===============
The following conventions have been used when calling ILAENV from the
LAPACK routines:
1) OPTS is a concatenation of all of the character options to
subroutine NAME, in the same order that they appear in the
argument list for NAME, even if they are not used in determining
the value of the parameter specified by ISPEC.
2) The problem dimensions N1, N2, N3, N4 are specified in the order
that they appear in the argument list for NAME. N1 is used
first, N2 second, and so on, and unused problem dimensions are
passed a value of -1.
3) The parameter value returned by ILAENV is checked for validity in
the calling subroutine. For example, ILAENV is used to retrieve
the optimal blocksize for STRTRI as follows:
NB = ILAENV( 1, 'STRTRI', UPLO // DIAG, N, -1, -1, -1 )
IF( NB.LE.1 ) NB = MAX( 1, N )
===================================================================== */
/* Table of constant values */
static integer c__0 = 0;
static real c_b162 = 0.f;
static real c_b163 = 1.f;
static integer c__1 = 1;
/* System generated locals */
integer ret_val;
/* Builtin functions
Subroutine */ int s_copy(char *, char *, ftnlen, ftnlen);
integer s_cmp(char *, char *, ftnlen, ftnlen);
/* Local variables */
static integer i__;
static logical cname, sname;
static integer nbmin;
static char c1[1], c2[2], c3[3], c4[2];
static integer ic, nb;
extern integer ieeeck_(integer *, real *, real *);
static integer iz, nx;
static char subnam[6];
switch (*ispec) {
case 1: goto L100;
case 2: goto L100;
case 3: goto L100;
case 4: goto L400;
case 5: goto L500;
case 6: goto L600;
case 7: goto L700;
case 8: goto L800;
case 9: goto L900;
case 10: goto L1000;
case 11: goto L1100;
}
/* Invalid value for ISPEC */
ret_val = -1;
return ret_val;
L100:
/* Convert NAME to upper case if the first character is lower case. */
ret_val = 1;
s_copy(subnam, name__, (ftnlen)6, name_len);
ic = *(unsigned char *)subnam;
iz = 'Z';
if (iz == 90 || iz == 122) {
/* ASCII character set */
if (ic >= 97 && ic <= 122) {
*(unsigned char *)subnam = (char) (ic - 32);
for (i__ = 2; i__ <= 6; ++i__) {
ic = *(unsigned char *)&subnam[i__ - 1];
if (ic >= 97 && ic <= 122) {
*(unsigned char *)&subnam[i__ - 1] = (char) (ic - 32);
}
/* L10: */
}
}
} else if (iz == 233 || iz == 169) {
/* EBCDIC character set */
if (ic >= 129 && ic <= 137 || ic >= 145 && ic <= 153 || ic >= 162 &&
ic <= 169) {
*(unsigned char *)subnam = (char) (ic + 64);
for (i__ = 2; i__ <= 6; ++i__) {
ic = *(unsigned char *)&subnam[i__ - 1];
if (ic >= 129 && ic <= 137 || ic >= 145 && ic <= 153 || ic >=
162 && ic <= 169) {
*(unsigned char *)&subnam[i__ - 1] = (char) (ic + 64);
}
/* L20: */
}
}
} else if (iz == 218 || iz == 250) {
/* Prime machines: ASCII+128 */
if (ic >= 225 && ic <= 250) {
*(unsigned char *)subnam = (char) (ic - 32);
for (i__ = 2; i__ <= 6; ++i__) {
ic = *(unsigned char *)&subnam[i__ - 1];
if (ic >= 225 && ic <= 250) {
*(unsigned char *)&subnam[i__ - 1] = (char) (ic - 32);
}
/* L30: */
}
}
}
*(unsigned char *)c1 = *(unsigned char *)subnam;
sname = *(unsigned char *)c1 == 'S' || *(unsigned char *)c1 == 'D';
cname = *(unsigned char *)c1 == 'C' || *(unsigned char *)c1 == 'Z';
if (! (cname || sname)) {
return ret_val;
}
s_copy(c2, subnam + 1, (ftnlen)2, (ftnlen)2);
s_copy(c3, subnam + 3, (ftnlen)3, (ftnlen)3);
s_copy(c4, c3 + 1, (ftnlen)2, (ftnlen)2);
switch (*ispec) {
case 1: goto L110;
case 2: goto L200;
case 3: goto L300;
}
L110:
/* ISPEC = 1: block size
In these examples, separate code is provided for setting NB for
real and complex. We assume that NB will take the same value in
single or double precision. */
nb = 1;
if (s_cmp(c2, "GE", (ftnlen)2, (ftnlen)2) == 0) {
if (s_cmp(c3, "TRF", (ftnlen)3, (ftnlen)3) == 0) {
if (sname) {
nb = 64;
} else {
nb = 64;
}
} else if (s_cmp(c3, "QRF", (ftnlen)3, (ftnlen)3) == 0 || s_cmp(c3,
"RQF", (ftnlen)3, (ftnlen)3) == 0 || s_cmp(c3, "LQF", (ftnlen)
3, (ftnlen)3) == 0 || s_cmp(c3, "QLF", (ftnlen)3, (ftnlen)3)
== 0) {
if (sname) {
nb = 32;
} else {
nb = 32;
}
} else if (s_cmp(c3, "HRD", (ftnlen)3, (ftnlen)3) == 0) {
if (sname) {
nb = 32;
} else {
nb = 32;
}
} else if (s_cmp(c3, "BRD", (ftnlen)3, (ftnlen)3) == 0) {
if (sname) {
nb = 32;
} else {
nb = 32;
}
} else if (s_cmp(c3, "TRI", (ftnlen)3, (ftnlen)3) == 0) {
if (sname) {
nb = 64;
} else {
nb = 64;
}
}
} else if (s_cmp(c2, "PO", (ftnlen)2, (ftnlen)2) == 0) {
if (s_cmp(c3, "TRF", (ftnlen)3, (ftnlen)3) == 0) {
if (sname) {
nb = 64;
} else {
nb = 64;
}
}
} else if (s_cmp(c2, "SY", (ftnlen)2, (ftnlen)2) == 0) {
if (s_cmp(c3, "TRF", (ftnlen)3, (ftnlen)3) == 0) {
if (sname) {
nb = 64;
} else {
nb = 64;
}
} else if (sname && s_cmp(c3, "TRD", (ftnlen)3, (ftnlen)3) == 0) {
nb = 32;
} else if (sname && s_cmp(c3, "GST", (ftnlen)3, (ftnlen)3) == 0) {
nb = 64;
}
} else if (cname && s_cmp(c2, "HE", (ftnlen)2, (ftnlen)2) == 0) {
if (s_cmp(c3, "TRF", (ftnlen)3, (ftnlen)3) == 0) {
nb = 64;
} else if (s_cmp(c3, "TRD", (ftnlen)3, (ftnlen)3) == 0) {
nb = 32;
} else if (s_cmp(c3, "GST", (ftnlen)3, (ftnlen)3) == 0) {
nb = 64;
}
} else if (sname && s_cmp(c2, "OR", (ftnlen)2, (ftnlen)2) == 0) {
if (*(unsigned char *)c3 == 'G') {
if (s_cmp(c4, "QR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "RQ",
(ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "LQ", (ftnlen)2, (
ftnlen)2) == 0 || s_cmp(c4, "QL", (ftnlen)2, (ftnlen)2) ==
0 || s_cmp(c4, "HR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(
c4, "TR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "BR", (
ftnlen)2, (ftnlen)2) == 0) {
nb = 32;
}
} else if (*(unsigned char *)c3 == 'M') {
if (s_cmp(c4, "QR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "RQ",
(ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "LQ", (ftnlen)2, (
ftnlen)2) == 0 || s_cmp(c4, "QL", (ftnlen)2, (ftnlen)2) ==
0 || s_cmp(c4, "HR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(
c4, "TR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "BR", (
ftnlen)2, (ftnlen)2) == 0) {
nb = 32;
}
}
} else if (cname && s_cmp(c2, "UN", (ftnlen)2, (ftnlen)2) == 0) {
if (*(unsigned char *)c3 == 'G') {
if (s_cmp(c4, "QR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "RQ",
(ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "LQ", (ftnlen)2, (
ftnlen)2) == 0 || s_cmp(c4, "QL", (ftnlen)2, (ftnlen)2) ==
0 || s_cmp(c4, "HR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(
c4, "TR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "BR", (
ftnlen)2, (ftnlen)2) == 0) {
nb = 32;
}
} else if (*(unsigned char *)c3 == 'M') {
if (s_cmp(c4, "QR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "RQ",
(ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "LQ", (ftnlen)2, (
ftnlen)2) == 0 || s_cmp(c4, "QL", (ftnlen)2, (ftnlen)2) ==
0 || s_cmp(c4, "HR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(
c4, "TR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "BR", (
ftnlen)2, (ftnlen)2) == 0) {
nb = 32;
}
}
} else if (s_cmp(c2, "GB", (ftnlen)2, (ftnlen)2) == 0) {
if (s_cmp(c3, "TRF", (ftnlen)3, (ftnlen)3) == 0) {
if (sname) {
if (*n4 <= 64) {
nb = 1;
} else {
nb = 32;
}
} else {
if (*n4 <= 64) {
nb = 1;
} else {
nb = 32;
}
}
}
} else if (s_cmp(c2, "PB", (ftnlen)2, (ftnlen)2) == 0) {
if (s_cmp(c3, "TRF", (ftnlen)3, (ftnlen)3) == 0) {
if (sname) {
if (*n2 <= 64) {
nb = 1;
} else {
nb = 32;
}
} else {
if (*n2 <= 64) {
nb = 1;
} else {
nb = 32;
}
}
}
} else if (s_cmp(c2, "TR", (ftnlen)2, (ftnlen)2) == 0) {
if (s_cmp(c3, "TRI", (ftnlen)3, (ftnlen)3) == 0) {
if (sname) {
nb = 64;
} else {
nb = 64;
}
}
} else if (s_cmp(c2, "LA", (ftnlen)2, (ftnlen)2) == 0) {
if (s_cmp(c3, "UUM", (ftnlen)3, (ftnlen)3) == 0) {
if (sname) {
nb = 64;
} else {
nb = 64;
}
}
} else if (sname && s_cmp(c2, "ST", (ftnlen)2, (ftnlen)2) == 0) {
if (s_cmp(c3, "EBZ", (ftnlen)3, (ftnlen)3) == 0) {
nb = 1;
}
}
ret_val = nb;
return ret_val;
L200:
/* ISPEC = 2: minimum block size */
nbmin = 2;
if (s_cmp(c2, "GE", (ftnlen)2, (ftnlen)2) == 0) {
if (s_cmp(c3, "QRF", (ftnlen)3, (ftnlen)3) == 0 || s_cmp(c3, "RQF", (
ftnlen)3, (ftnlen)3) == 0 || s_cmp(c3, "LQF", (ftnlen)3, (
ftnlen)3) == 0 || s_cmp(c3, "QLF", (ftnlen)3, (ftnlen)3) == 0)
{
if (sname) {
nbmin = 2;
} else {
nbmin = 2;
}
} else if (s_cmp(c3, "HRD", (ftnlen)3, (ftnlen)3) == 0) {
if (sname) {
nbmin = 2;
} else {
nbmin = 2;
}
} else if (s_cmp(c3, "BRD", (ftnlen)3, (ftnlen)3) == 0) {
if (sname) {
nbmin = 2;
} else {
nbmin = 2;
}
} else if (s_cmp(c3, "TRI", (ftnlen)3, (ftnlen)3) == 0) {
if (sname) {
nbmin = 2;
} else {
nbmin = 2;
}
}
} else if (s_cmp(c2, "SY", (ftnlen)2, (ftnlen)2) == 0) {
if (s_cmp(c3, "TRF", (ftnlen)3, (ftnlen)3) == 0) {
if (sname) {
nbmin = 8;
} else {
nbmin = 8;
}
} else if (sname && s_cmp(c3, "TRD", (ftnlen)3, (ftnlen)3) == 0) {
nbmin = 2;
}
} else if (cname && s_cmp(c2, "HE", (ftnlen)2, (ftnlen)2) == 0) {
if (s_cmp(c3, "TRD", (ftnlen)3, (ftnlen)3) == 0) {
nbmin = 2;
}
} else if (sname && s_cmp(c2, "OR", (ftnlen)2, (ftnlen)2) == 0) {
if (*(unsigned char *)c3 == 'G') {
if (s_cmp(c4, "QR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "RQ",
(ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "LQ", (ftnlen)2, (
ftnlen)2) == 0 || s_cmp(c4, "QL", (ftnlen)2, (ftnlen)2) ==
0 || s_cmp(c4, "HR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(
c4, "TR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "BR", (
ftnlen)2, (ftnlen)2) == 0) {
nbmin = 2;
}
} else if (*(unsigned char *)c3 == 'M') {
if (s_cmp(c4, "QR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "RQ",
(ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "LQ", (ftnlen)2, (
ftnlen)2) == 0 || s_cmp(c4, "QL", (ftnlen)2, (ftnlen)2) ==
0 || s_cmp(c4, "HR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(
c4, "TR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "BR", (
ftnlen)2, (ftnlen)2) == 0) {
nbmin = 2;
}
}
} else if (cname && s_cmp(c2, "UN", (ftnlen)2, (ftnlen)2) == 0) {
if (*(unsigned char *)c3 == 'G') {
if (s_cmp(c4, "QR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "RQ",
(ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "LQ", (ftnlen)2, (
ftnlen)2) == 0 || s_cmp(c4, "QL", (ftnlen)2, (ftnlen)2) ==
0 || s_cmp(c4, "HR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(
c4, "TR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "BR", (
ftnlen)2, (ftnlen)2) == 0) {
nbmin = 2;
}
} else if (*(unsigned char *)c3 == 'M') {
if (s_cmp(c4, "QR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "RQ",
(ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "LQ", (ftnlen)2, (
ftnlen)2) == 0 || s_cmp(c4, "QL", (ftnlen)2, (ftnlen)2) ==
0 || s_cmp(c4, "HR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(
c4, "TR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "BR", (
ftnlen)2, (ftnlen)2) == 0) {
nbmin = 2;
}
}
}
ret_val = nbmin;
return ret_val;
L300:
/* ISPEC = 3: crossover point */
nx = 0;
if (s_cmp(c2, "GE", (ftnlen)2, (ftnlen)2) == 0) {
if (s_cmp(c3, "QRF", (ftnlen)3, (ftnlen)3) == 0 || s_cmp(c3, "RQF", (
ftnlen)3, (ftnlen)3) == 0 || s_cmp(c3, "LQF", (ftnlen)3, (
ftnlen)3) == 0 || s_cmp(c3, "QLF", (ftnlen)3, (ftnlen)3) == 0)
{
if (sname) {
nx = 128;
} else {
nx = 128;
}
} else if (s_cmp(c3, "HRD", (ftnlen)3, (ftnlen)3) == 0) {
if (sname) {
nx = 128;
} else {
nx = 128;
}
} else if (s_cmp(c3, "BRD", (ftnlen)3, (ftnlen)3) == 0) {
if (sname) {
nx = 128;
} else {
nx = 128;
}
}
} else if (s_cmp(c2, "SY", (ftnlen)2, (ftnlen)2) == 0) {
if (sname && s_cmp(c3, "TRD", (ftnlen)3, (ftnlen)3) == 0) {
nx = 32;
}
} else if (cname && s_cmp(c2, "HE", (ftnlen)2, (ftnlen)2) == 0) {
if (s_cmp(c3, "TRD", (ftnlen)3, (ftnlen)3) == 0) {
nx = 32;
}
} else if (sname && s_cmp(c2, "OR", (ftnlen)2, (ftnlen)2) == 0) {
if (*(unsigned char *)c3 == 'G') {
if (s_cmp(c4, "QR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "RQ",
(ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "LQ", (ftnlen)2, (
ftnlen)2) == 0 || s_cmp(c4, "QL", (ftnlen)2, (ftnlen)2) ==
0 || s_cmp(c4, "HR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(
c4, "TR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "BR", (
ftnlen)2, (ftnlen)2) == 0) {
nx = 128;
}
}
} else if (cname && s_cmp(c2, "UN", (ftnlen)2, (ftnlen)2) == 0) {
if (*(unsigned char *)c3 == 'G') {
if (s_cmp(c4, "QR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "RQ",
(ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "LQ", (ftnlen)2, (
ftnlen)2) == 0 || s_cmp(c4, "QL", (ftnlen)2, (ftnlen)2) ==
0 || s_cmp(c4, "HR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(
c4, "TR", (ftnlen)2, (ftnlen)2) == 0 || s_cmp(c4, "BR", (
ftnlen)2, (ftnlen)2) == 0) {
nx = 128;
}
}
}
ret_val = nx;
return ret_val;
L400:
/* ISPEC = 4: number of shifts (used by xHSEQR) */
ret_val = 6;
return ret_val;
L500:
/* ISPEC = 5: minimum column dimension (not used) */
ret_val = 2;
return ret_val;
L600:
/* ISPEC = 6: crossover point for SVD (used by xGELSS and xGESVD) */
ret_val = (integer) ((real) min(*n1,*n2) * 1.6f);
return ret_val;
L700:
/* ISPEC = 7: number of processors (not used) */
ret_val = 1;
return ret_val;
L800:
/* ISPEC = 8: crossover point for multishift (used by xHSEQR) */
ret_val = 50;
return ret_val;
L900:
/* ISPEC = 9: maximum size of the subproblems at the bottom of the
computation tree in the divide-and-conquer algorithm
(used by xGELSD and xGESDD) */
ret_val = 25;
return ret_val;
L1000:
/* ISPEC = 10: ieee NaN arithmetic can be trusted not to trap
ILAENV = 0 */
ret_val = 1;
if (ret_val == 1) {
ret_val = ieeeck_(&c__0, &c_b162, &c_b163);
}
return ret_val;
L1100:
/* ISPEC = 11: infinity arithmetic can be trusted not to trap
ILAENV = 0 */
ret_val = 1;
if (ret_val == 1) {
ret_val = ieeeck_(&c__1, &c_b162, &c_b163);
}
return ret_val;
/* End of ILAENV */
} /* ilaenv_ */
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