OpenBLAS/relapack/src/zsytrf_rec2.c

453 lines
13 KiB
C

/* -- translated by f2c (version 20100827).
You must link the resulting object file with libf2c:
on Microsoft Windows system, link with libf2c.lib;
on Linux or Unix systems, link with .../path/to/libf2c.a -lm
or, if you install libf2c.a in a standard place, with -lf2c -lm
-- in that order, at the end of the command line, as in
cc *.o -lf2c -lm
Source for libf2c is in /netlib/f2c/libf2c.zip, e.g.,
http://www.netlib.org/f2c/libf2c.zip
*/
#include "f2c.h"
/* Table of constant values */
static doublecomplex c_b1 = {1.,0.};
static blasint c__1 = 1;
/** ZSYTRF_REC2 computes a partial factorization of a complex symmetric matrix using the Bunch-Kaufman diagon al pivoting method.
*
* This routine is a minor modification of LAPACK's zlasyf.
* It serves as an unblocked kernel in the recursive algorithms.
* The blocked BLAS Level 3 updates were removed and moved to the
* recursive algorithm.
* */
/* Subroutine */ void RELAPACK_zsytrf_rec2(char *uplo, blasint *n, blasint *
nb, blasint *kb, doublecomplex *a, blasint *lda, blasint *ipiv,
doublecomplex *w, blasint *ldw, blasint *info, ftnlen uplo_len)
{
/* System generated locals */
blasint a_dim1, a_offset, w_dim1, w_offset, i__1, i__2, i__3, i__4;
double d__1, d__2, d__3, d__4;
doublecomplex z__1, z__2, z__3;
/* Builtin functions */
double sqrt(double), d_imag(doublecomplex *);
void z_div(doublecomplex *, doublecomplex *, doublecomplex *);
/* Local variables */
static blasint j, k;
static doublecomplex t, r1, d11, d21, d22;
static blasint jj, kk, jp, kp, kw, kkw, imax, jmax;
static double alpha;
extern logical lsame_(char *, char *, ftnlen, ftnlen);
extern /* Subroutine */ blasint zscal_(int *, doublecomplex *,
doublecomplex *, blasint *);
static blasint kstep;
extern /* Subroutine */ blasint zgemv_(char *, blasint *, blasint *,
doublecomplex *, doublecomplex *, blasint *, doublecomplex *,
blasint *, doublecomplex *, doublecomplex *, blasint *, ftnlen),
zcopy_(int *, doublecomplex *, blasint *, doublecomplex *,
blasint *), zswap_(int *, doublecomplex *, blasint *,
doublecomplex *, blasint *);
static double absakk, colmax;
extern blasint izamax_(int *, doublecomplex *, blasint *);
static double rowmax;
/* Parameter adjustments */
a_dim1 = *lda;
a_offset = 1 + a_dim1;
a -= a_offset;
--ipiv;
w_dim1 = *ldw;
w_offset = 1 + w_dim1;
w -= w_offset;
/* Function Body */
*info = 0;
alpha = (sqrt(17.) + 1.) / 8.;
if (lsame_(uplo, "U", (ftnlen)1, (ftnlen)1)) {
k = *n;
L10:
kw = *nb + k - *n;
if ((k <= *n - *nb + 1 && *nb < *n) || k < 1) {
goto L30;
}
zcopy_(&k, &a[k * a_dim1 + 1], &c__1, &w[kw * w_dim1 + 1], &c__1);
if (k < *n) {
i__1 = *n - k;
z__1.r = -1., z__1.i = -0.;
zgemv_("No transpose", &k, &i__1, &z__1, &a[(k + 1) * a_dim1 + 1],
lda, &w[k + (kw + 1) * w_dim1], ldw, &c_b1, &w[kw *
w_dim1 + 1], &c__1, (ftnlen)12);
}
kstep = 1;
i__1 = k + kw * w_dim1;
absakk = (d__1 = w[i__1].r, abs(d__1)) + (d__2 = d_imag(&w[k + kw *
w_dim1]), abs(d__2));
if (k > 1) {
i__1 = k - 1;
imax = izamax_(&i__1, &w[kw * w_dim1 + 1], &c__1);
i__1 = imax + kw * w_dim1;
colmax = (d__1 = w[i__1].r, abs(d__1)) + (d__2 = d_imag(&w[imax +
kw * w_dim1]), abs(d__2));
} else {
colmax = 0.;
}
if (max(absakk,colmax) == 0.) {
if (*info == 0) {
*info = k;
}
kp = k;
} else {
if (absakk >= alpha * colmax) {
kp = k;
} else {
zcopy_(&imax, &a[imax * a_dim1 + 1], &c__1, &w[(kw - 1) *
w_dim1 + 1], &c__1);
i__1 = k - imax;
zcopy_(&i__1, &a[imax + (imax + 1) * a_dim1], lda, &w[imax +
1 + (kw - 1) * w_dim1], &c__1);
if (k < *n) {
i__1 = *n - k;
z__1.r = -1., z__1.i = -0.;
zgemv_("No transpose", &k, &i__1, &z__1, &a[(k + 1) *
a_dim1 + 1], lda, &w[imax + (kw + 1) * w_dim1],
ldw, &c_b1, &w[(kw - 1) * w_dim1 + 1], &c__1, (
ftnlen)12);
}
i__1 = k - imax;
jmax = imax + izamax_(&i__1, &w[imax + 1 + (kw - 1) * w_dim1],
&c__1);
i__1 = jmax + (kw - 1) * w_dim1;
rowmax = (d__1 = w[i__1].r, abs(d__1)) + (d__2 = d_imag(&w[
jmax + (kw - 1) * w_dim1]), abs(d__2));
if (imax > 1) {
i__1 = imax - 1;
jmax = izamax_(&i__1, &w[(kw - 1) * w_dim1 + 1], &c__1);
/* Computing MAX */
i__1 = jmax + (kw - 1) * w_dim1;
d__3 = rowmax, d__4 = (d__1 = w[i__1].r, abs(d__1)) + (
d__2 = d_imag(&w[jmax + (kw - 1) * w_dim1]), abs(
d__2));
rowmax = max(d__3,d__4);
}
if (absakk >= alpha * colmax * (colmax / rowmax)) {
kp = k;
} else /* if(complicated condition) */ {
i__1 = imax + (kw - 1) * w_dim1;
if ((d__1 = w[i__1].r, abs(d__1)) + (d__2 = d_imag(&w[
imax + (kw - 1) * w_dim1]), abs(d__2)) >= alpha *
rowmax) {
kp = imax;
zcopy_(&k, &w[(kw - 1) * w_dim1 + 1], &c__1, &w[kw *
w_dim1 + 1], &c__1);
} else {
kp = imax;
kstep = 2;
}
}
}
kk = k - kstep + 1;
kkw = *nb + kk - *n;
if (kp != kk) {
i__1 = kp + kp * a_dim1;
i__2 = kk + kk * a_dim1;
a[i__1].r = a[i__2].r, a[i__1].i = a[i__2].i;
i__1 = kk - 1 - kp;
zcopy_(&i__1, &a[kp + 1 + kk * a_dim1], &c__1, &a[kp + (kp +
1) * a_dim1], lda);
if (kp > 1) {
i__1 = kp - 1;
zcopy_(&i__1, &a[kk * a_dim1 + 1], &c__1, &a[kp * a_dim1
+ 1], &c__1);
}
if (k < *n) {
i__1 = *n - k;
zswap_(&i__1, &a[kk + (k + 1) * a_dim1], lda, &a[kp + (k
+ 1) * a_dim1], lda);
}
i__1 = *n - kk + 1;
zswap_(&i__1, &w[kk + kkw * w_dim1], ldw, &w[kp + kkw *
w_dim1], ldw);
}
if (kstep == 1) {
zcopy_(&k, &w[kw * w_dim1 + 1], &c__1, &a[k * a_dim1 + 1], &
c__1);
z_div(&z__1, &c_b1, &a[k + k * a_dim1]);
r1.r = z__1.r, r1.i = z__1.i;
i__1 = k - 1;
zscal_(&i__1, &r1, &a[k * a_dim1 + 1], &c__1);
} else {
if (k > 2) {
i__1 = k - 1 + kw * w_dim1;
d21.r = w[i__1].r, d21.i = w[i__1].i;
z_div(&z__1, &w[k + kw * w_dim1], &d21);
d11.r = z__1.r, d11.i = z__1.i;
z_div(&z__1, &w[k - 1 + (kw - 1) * w_dim1], &d21);
d22.r = z__1.r, d22.i = z__1.i;
z__3.r = d11.r * d22.r - d11.i * d22.i, z__3.i = d11.r *
d22.i + d11.i * d22.r;
z__2.r = z__3.r - 1., z__2.i = z__3.i - 0.;
z_div(&z__1, &c_b1, &z__2);
t.r = z__1.r, t.i = z__1.i;
z_div(&z__1, &t, &d21);
d21.r = z__1.r, d21.i = z__1.i;
i__1 = k - 2;
for (j = 1; j <= i__1; ++j) {
i__2 = j + (k - 1) * a_dim1;
i__3 = j + (kw - 1) * w_dim1;
z__3.r = d11.r * w[i__3].r - d11.i * w[i__3].i,
z__3.i = d11.r * w[i__3].i + d11.i * w[i__3]
.r;
i__4 = j + kw * w_dim1;
z__2.r = z__3.r - w[i__4].r, z__2.i = z__3.i - w[i__4]
.i;
z__1.r = d21.r * z__2.r - d21.i * z__2.i, z__1.i =
d21.r * z__2.i + d21.i * z__2.r;
a[i__2].r = z__1.r, a[i__2].i = z__1.i;
i__2 = j + k * a_dim1;
i__3 = j + kw * w_dim1;
z__3.r = d22.r * w[i__3].r - d22.i * w[i__3].i,
z__3.i = d22.r * w[i__3].i + d22.i * w[i__3]
.r;
i__4 = j + (kw - 1) * w_dim1;
z__2.r = z__3.r - w[i__4].r, z__2.i = z__3.i - w[i__4]
.i;
z__1.r = d21.r * z__2.r - d21.i * z__2.i, z__1.i =
d21.r * z__2.i + d21.i * z__2.r;
a[i__2].r = z__1.r, a[i__2].i = z__1.i;
/* L20: */
}
}
i__1 = k - 1 + (k - 1) * a_dim1;
i__2 = k - 1 + (kw - 1) * w_dim1;
a[i__1].r = w[i__2].r, a[i__1].i = w[i__2].i;
i__1 = k - 1 + k * a_dim1;
i__2 = k - 1 + kw * w_dim1;
a[i__1].r = w[i__2].r, a[i__1].i = w[i__2].i;
i__1 = k + k * a_dim1;
i__2 = k + kw * w_dim1;
a[i__1].r = w[i__2].r, a[i__1].i = w[i__2].i;
}
}
if (kstep == 1) {
ipiv[k] = kp;
} else {
ipiv[k] = -kp;
ipiv[k - 1] = -kp;
}
k -= kstep;
goto L10;
L30:
j = k + 1;
L60:
jj = j;
jp = ipiv[j];
if (jp < 0) {
jp = -jp;
++j;
}
++j;
if (jp != jj && j <= *n) {
i__1 = *n - j + 1;
zswap_(&i__1, &a[jp + j * a_dim1], lda, &a[jj + j * a_dim1], lda);
}
if (j < *n) {
goto L60;
}
*kb = *n - k;
} else {
k = 1;
L70:
if ((k >= *nb && *nb < *n) || k > *n) {
goto L90;
}
i__1 = *n - k + 1;
zcopy_(&i__1, &a[k + k * a_dim1], &c__1, &w[k + k * w_dim1], &c__1);
i__1 = *n - k + 1;
i__2 = k - 1;
z__1.r = -1., z__1.i = -0.;
zgemv_("No transpose", &i__1, &i__2, &z__1, &a[k + a_dim1], lda, &w[k
+ w_dim1], ldw, &c_b1, &w[k + k * w_dim1], &c__1, (ftnlen)12);
kstep = 1;
i__1 = k + k * w_dim1;
absakk = (d__1 = w[i__1].r, abs(d__1)) + (d__2 = d_imag(&w[k + k *
w_dim1]), abs(d__2));
if (k < *n) {
i__1 = *n - k;
imax = k + izamax_(&i__1, &w[k + 1 + k * w_dim1], &c__1);
i__1 = imax + k * w_dim1;
colmax = (d__1 = w[i__1].r, abs(d__1)) + (d__2 = d_imag(&w[imax +
k * w_dim1]), abs(d__2));
} else {
colmax = 0.;
}
if (max(absakk,colmax) == 0.) {
if (*info == 0) {
*info = k;
}
kp = k;
} else {
if (absakk >= alpha * colmax) {
kp = k;
} else {
i__1 = imax - k;
zcopy_(&i__1, &a[imax + k * a_dim1], lda, &w[k + (k + 1) *
w_dim1], &c__1);
i__1 = *n - imax + 1;
zcopy_(&i__1, &a[imax + imax * a_dim1], &c__1, &w[imax + (k +
1) * w_dim1], &c__1);
i__1 = *n - k + 1;
i__2 = k - 1;
z__1.r = -1., z__1.i = -0.;
zgemv_("No transpose", &i__1, &i__2, &z__1, &a[k + a_dim1],
lda, &w[imax + w_dim1], ldw, &c_b1, &w[k + (k + 1) *
w_dim1], &c__1, (ftnlen)12);
i__1 = imax - k;
jmax = k - 1 + izamax_(&i__1, &w[k + (k + 1) * w_dim1], &c__1)
;
i__1 = jmax + (k + 1) * w_dim1;
rowmax = (d__1 = w[i__1].r, abs(d__1)) + (d__2 = d_imag(&w[
jmax + (k + 1) * w_dim1]), abs(d__2));
if (imax < *n) {
i__1 = *n - imax;
jmax = imax + izamax_(&i__1, &w[imax + 1 + (k + 1) *
w_dim1], &c__1);
/* Computing MAX */
i__1 = jmax + (k + 1) * w_dim1;
d__3 = rowmax, d__4 = (d__1 = w[i__1].r, abs(d__1)) + (
d__2 = d_imag(&w[jmax + (k + 1) * w_dim1]), abs(
d__2));
rowmax = max(d__3,d__4);
}
if (absakk >= alpha * colmax * (colmax / rowmax)) {
kp = k;
} else /* if(complicated condition) */ {
i__1 = imax + (k + 1) * w_dim1;
if ((d__1 = w[i__1].r, abs(d__1)) + (d__2 = d_imag(&w[
imax + (k + 1) * w_dim1]), abs(d__2)) >= alpha *
rowmax) {
kp = imax;
i__1 = *n - k + 1;
zcopy_(&i__1, &w[k + (k + 1) * w_dim1], &c__1, &w[k +
k * w_dim1], &c__1);
} else {
kp = imax;
kstep = 2;
}
}
}
kk = k + kstep - 1;
if (kp != kk) {
i__1 = kp + kp * a_dim1;
i__2 = kk + kk * a_dim1;
a[i__1].r = a[i__2].r, a[i__1].i = a[i__2].i;
i__1 = kp - kk - 1;
zcopy_(&i__1, &a[kk + 1 + kk * a_dim1], &c__1, &a[kp + (kk +
1) * a_dim1], lda);
if (kp < *n) {
i__1 = *n - kp;
zcopy_(&i__1, &a[kp + 1 + kk * a_dim1], &c__1, &a[kp + 1
+ kp * a_dim1], &c__1);
}
if (k > 1) {
i__1 = k - 1;
zswap_(&i__1, &a[kk + a_dim1], lda, &a[kp + a_dim1], lda);
}
zswap_(&kk, &w[kk + w_dim1], ldw, &w[kp + w_dim1], ldw);
}
if (kstep == 1) {
i__1 = *n - k + 1;
zcopy_(&i__1, &w[k + k * w_dim1], &c__1, &a[k + k * a_dim1], &
c__1);
if (k < *n) {
z_div(&z__1, &c_b1, &a[k + k * a_dim1]);
r1.r = z__1.r, r1.i = z__1.i;
i__1 = *n - k;
zscal_(&i__1, &r1, &a[k + 1 + k * a_dim1], &c__1);
}
} else {
if (k < *n - 1) {
i__1 = k + 1 + k * w_dim1;
d21.r = w[i__1].r, d21.i = w[i__1].i;
z_div(&z__1, &w[k + 1 + (k + 1) * w_dim1], &d21);
d11.r = z__1.r, d11.i = z__1.i;
z_div(&z__1, &w[k + k * w_dim1], &d21);
d22.r = z__1.r, d22.i = z__1.i;
z__3.r = d11.r * d22.r - d11.i * d22.i, z__3.i = d11.r *
d22.i + d11.i * d22.r;
z__2.r = z__3.r - 1., z__2.i = z__3.i - 0.;
z_div(&z__1, &c_b1, &z__2);
t.r = z__1.r, t.i = z__1.i;
z_div(&z__1, &t, &d21);
d21.r = z__1.r, d21.i = z__1.i;
i__1 = *n;
for (j = k + 2; j <= i__1; ++j) {
i__2 = j + k * a_dim1;
i__3 = j + k * w_dim1;
z__3.r = d11.r * w[i__3].r - d11.i * w[i__3].i,
z__3.i = d11.r * w[i__3].i + d11.i * w[i__3]
.r;
i__4 = j + (k + 1) * w_dim1;
z__2.r = z__3.r - w[i__4].r, z__2.i = z__3.i - w[i__4]
.i;
z__1.r = d21.r * z__2.r - d21.i * z__2.i, z__1.i =
d21.r * z__2.i + d21.i * z__2.r;
a[i__2].r = z__1.r, a[i__2].i = z__1.i;
i__2 = j + (k + 1) * a_dim1;
i__3 = j + (k + 1) * w_dim1;
z__3.r = d22.r * w[i__3].r - d22.i * w[i__3].i,
z__3.i = d22.r * w[i__3].i + d22.i * w[i__3]
.r;
i__4 = j + k * w_dim1;
z__2.r = z__3.r - w[i__4].r, z__2.i = z__3.i - w[i__4]
.i;
z__1.r = d21.r * z__2.r - d21.i * z__2.i, z__1.i =
d21.r * z__2.i + d21.i * z__2.r;
a[i__2].r = z__1.r, a[i__2].i = z__1.i;
/* L80: */
}
}
i__1 = k + k * a_dim1;
i__2 = k + k * w_dim1;
a[i__1].r = w[i__2].r, a[i__1].i = w[i__2].i;
i__1 = k + 1 + k * a_dim1;
i__2 = k + 1 + k * w_dim1;
a[i__1].r = w[i__2].r, a[i__1].i = w[i__2].i;
i__1 = k + 1 + (k + 1) * a_dim1;
i__2 = k + 1 + (k + 1) * w_dim1;
a[i__1].r = w[i__2].r, a[i__1].i = w[i__2].i;
}
}
if (kstep == 1) {
ipiv[k] = kp;
} else {
ipiv[k] = -kp;
ipiv[k + 1] = -kp;
}
k += kstep;
goto L70;
L90:
j = k - 1;
L120:
jj = j;
jp = ipiv[j];
if (jp < 0) {
jp = -jp;
--j;
}
--j;
if (jp != jj && j >= 1) {
zswap_(&j, &a[jp + a_dim1], lda, &a[jj + a_dim1], lda);
}
if (j > 1) {
goto L120;
}
*kb = k - 1;
}
return;
}