1 /* ---------------------------------------------------------------------
2 *
3 * -- PBLAS routine (version 2.0) --
4 * University of Tennessee, Knoxville, Oak Ridge National Laboratory,
5 * and University of California, Berkeley.
6 * April 1, 1998
7 *
8 * ---------------------------------------------------------------------
9 */
10 /*
11 * Include files
12 */
13 #include "pblas.h"
14 #include "PBpblas.h"
15 #include "PBtools.h"
16 #include "PBblacs.h"
17 #include "PBblas.h"
18
19 #ifdef __STDC__
pcgeadd_(F_CHAR_T TRANS,int * M,int * N,float * ALPHA,float * A,int * IA,int * JA,int * DESCA,float * BETA,float * C,int * IC,int * JC,int * DESCC)20 void pcgeadd_( F_CHAR_T TRANS, int * M, int * N,
21 float * ALPHA,
22 float * A, int * IA, int * JA, int * DESCA,
23 float * BETA,
24 float * C, int * IC, int * JC, int * DESCC )
25 #else
26 void pcgeadd_( TRANS, M, N, ALPHA, A, IA, JA, DESCA, BETA, C, IC, JC, DESCC )
27 /*
28 * .. Scalar Arguments ..
29 */
30 F_CHAR_T TRANS;
31 int * IA, * IC, * JA, * JC, * M, * N;
32 float * ALPHA, * BETA;
33 /*
34 * .. Array Arguments ..
35 */
36 int * DESCA, * DESCC;
37 float * A, * C;
38 #endif
39 {
40 /*
41 * Purpose
42 * =======
43 *
44 * PCGEADD adds a matrix to another
45 *
46 * sub( C ) := beta*sub( C ) + alpha*op( sub( A ) )
47 *
48 * where
49 *
50 * sub( C ) denotes C(IC:IC+M-1,JC:JC+N-1), and, op( X ) is one of
51 *
52 * op( X ) = X or op( X ) = X' or op( X ) = conjg( X' ).
53 *
54 * Thus, op( sub( A ) ) denotes A(IA:IA+M-1,JA:JA+N-1) if TRANS = 'N',
55 * A(IA:IA+N-1,JA:JA+M-1)' if TRANS = 'T',
56 * conjg(A(IA:IA+N-1,JA:JA+M-1)') if TRANS = 'C'.
57 *
58 * Alpha and beta are scalars, sub( C ) and op( sub( A ) ) are m by n
59 * submatrices.
60 *
61 * Notes
62 * =====
63 *
64 * A description vector is associated with each 2D block-cyclicly dis-
65 * tributed matrix. This vector stores the information required to
66 * establish the mapping between a matrix entry and its corresponding
67 * process and memory location.
68 *
69 * In the following comments, the character _ should be read as
70 * "of the distributed matrix". Let A be a generic term for any 2D
71 * block cyclicly distributed matrix. Its description vector is DESC_A:
72 *
73 * NOTATION STORED IN EXPLANATION
74 * ---------------- --------------- ------------------------------------
75 * DTYPE_A (global) DESCA[ DTYPE_ ] The descriptor type.
76 * CTXT_A (global) DESCA[ CTXT_ ] The BLACS context handle, indicating
77 * the NPROW x NPCOL BLACS process grid
78 * A is distributed over. The context
79 * itself is global, but the handle
80 * (the integer value) may vary.
81 * M_A (global) DESCA[ M_ ] The number of rows in the distribu-
82 * ted matrix A, M_A >= 0.
83 * N_A (global) DESCA[ N_ ] The number of columns in the distri-
84 * buted matrix A, N_A >= 0.
85 * IMB_A (global) DESCA[ IMB_ ] The number of rows of the upper left
86 * block of the matrix A, IMB_A > 0.
87 * INB_A (global) DESCA[ INB_ ] The number of columns of the upper
88 * left block of the matrix A,
89 * INB_A > 0.
90 * MB_A (global) DESCA[ MB_ ] The blocking factor used to distri-
91 * bute the last M_A-IMB_A rows of A,
92 * MB_A > 0.
93 * NB_A (global) DESCA[ NB_ ] The blocking factor used to distri-
94 * bute the last N_A-INB_A columns of
95 * A, NB_A > 0.
96 * RSRC_A (global) DESCA[ RSRC_ ] The process row over which the first
97 * row of the matrix A is distributed,
98 * NPROW > RSRC_A >= 0.
99 * CSRC_A (global) DESCA[ CSRC_ ] The process column over which the
100 * first column of A is distributed.
101 * NPCOL > CSRC_A >= 0.
102 * LLD_A (local) DESCA[ LLD_ ] The leading dimension of the local
103 * array storing the local blocks of
104 * the distributed matrix A,
105 * IF( Lc( 1, N_A ) > 0 )
106 * LLD_A >= MAX( 1, Lr( 1, M_A ) )
107 * ELSE
108 * LLD_A >= 1.
109 *
110 * Let K be the number of rows of a matrix A starting at the global in-
111 * dex IA,i.e, A( IA:IA+K-1, : ). Lr( IA, K ) denotes the number of rows
112 * that the process of row coordinate MYROW ( 0 <= MYROW < NPROW ) would
113 * receive if these K rows were distributed over NPROW processes. If K
114 * is the number of columns of a matrix A starting at the global index
115 * JA, i.e, A( :, JA:JA+K-1, : ), Lc( JA, K ) denotes the number of co-
116 * lumns that the process MYCOL ( 0 <= MYCOL < NPCOL ) would receive if
117 * these K columns were distributed over NPCOL processes.
118 *
119 * The values of Lr() and Lc() may be determined via a call to the func-
120 * tion PB_Cnumroc:
121 * Lr( IA, K ) = PB_Cnumroc( K, IA, IMB_A, MB_A, MYROW, RSRC_A, NPROW )
122 * Lc( JA, K ) = PB_Cnumroc( K, JA, INB_A, NB_A, MYCOL, CSRC_A, NPCOL )
123 *
124 * Arguments
125 * =========
126 *
127 * TRANS (global input) CHARACTER*1
128 * On entry, TRANS specifies the form of op( sub( A ) ) to be
129 * used in the matrix addition as follows:
130 *
131 * TRANS = 'N' or 'n' op( sub( A ) ) = sub( A ),
132 *
133 * TRANS = 'T' or 't' op( sub( A ) ) = sub( A )',
134 *
135 * TRANS = 'C' or 'c' op( sub( A ) ) = conjg( sub( A )' ).
136 *
137 * M (global input) INTEGER
138 * On entry, M specifies the number of rows of the submatrix
139 * sub( C ) and the number of columns of the submatrix sub( A ).
140 * M must be at least zero.
141 *
142 * N (global input) INTEGER
143 * On entry, N specifies the number of columns of the submatrix
144 * sub( C ) and the number of rows of the submatrix sub( A ). N
145 * must be at least zero.
146 *
147 * ALPHA (global input) COMPLEX
148 * On entry, ALPHA specifies the scalar alpha. When ALPHA is
149 * supplied as zero then the local entries of the array A
150 * corresponding to the entries of the submatrix sub( A ) need
151 * not be set on input.
152 *
153 * A (local input) COMPLEX array
154 * On entry, A is an array of dimension (LLD_A, Ka), where Ka is
155 * at least Lc( 1, JA+M-1 ). Before entry, this array contains
156 * the local entries of the matrix A.
157 *
158 * IA (global input) INTEGER
159 * On entry, IA specifies A's global row index, which points to
160 * the beginning of the submatrix sub( A ).
161 *
162 * JA (global input) INTEGER
163 * On entry, JA specifies A's global column index, which points
164 * to the beginning of the submatrix sub( A ).
165 *
166 * DESCA (global and local input) INTEGER array
167 * On entry, DESCA is an integer array of dimension DLEN_. This
168 * is the array descriptor for the matrix A.
169 *
170 * BETA (global input) COMPLEX
171 * On entry, BETA specifies the scalar beta. When BETA is
172 * supplied as zero then the local entries of the array C
173 * corresponding to the entries of the submatrix sub( C ) need
174 * not be set on input.
175 *
176 * C (local input/local output) COMPLEX array
177 * On entry, C is an array of dimension (LLD_C, Kc), where Kc is
178 * at least Lc( 1, JC+N-1 ). Before entry, this array contains
179 * the local entries of the matrix C.
180 * On exit, the entries of this array corresponding to the local
181 * entries of the submatrix sub( C ) are overwritten by the
182 * local entries of the m by n updated submatrix.
183 *
184 * IC (global input) INTEGER
185 * On entry, IC specifies C's global row index, which points to
186 * the beginning of the submatrix sub( C ).
187 *
188 * JC (global input) INTEGER
189 * On entry, JC specifies C's global column index, which points
190 * to the beginning of the submatrix sub( C ).
191 *
192 * DESCC (global and local input) INTEGER array
193 * On entry, DESCC is an integer array of dimension DLEN_. This
194 * is the array descriptor for the matrix C.
195 *
196 * -- Written on April 1, 1998 by
197 * Antoine Petitet, University of Tennessee, Knoxville 37996, USA.
198 *
199 * ---------------------------------------------------------------------
200 */
201 /*
202 * .. Local Scalars ..
203 */
204 char DirA, DirC, ctop, rtop;
205 int Ai, Aj, Ci, Cj, TrA, ctxt, info, mycol, myrow, npcol, nprow,
206 notran;
207 /*
208 * .. Local Arrays ..
209 */
210 int Ad[DLEN_], Cd[DLEN_];
211 /* ..
212 * .. Executable Statements ..
213 *
214 */
215 notran = ( ( TrA = Mupcase( F2C_CHAR( TRANS )[0] ) ) == CNOTRAN );
216 PB_CargFtoC( *IA, *JA, DESCA, &Ai, &Aj, Ad );
217 PB_CargFtoC( *IC, *JC, DESCC, &Ci, &Cj, Cd );
218 #ifndef NO_ARGCHK
219 /*
220 * Test the input parameters
221 */
222 Cblacs_gridinfo( ( ctxt = Ad[CTXT_] ), &nprow, &npcol, &myrow, &mycol );
223 if( !( info = ( ( nprow == -1 ) ? -( 801 + CTXT_ ) : 0 ) ) )
224 {
225 if( ( !notran ) && ( TrA != CTRAN ) && ( TrA != CCOTRAN ) )
226 {
227 PB_Cwarn( ctxt, __LINE__, "PCGEADD", "Illegal TRANS = %c\n", TrA );
228 info = -1;
229 }
230 if( notran )
231 PB_Cchkmat( ctxt, "PCGEADD", "A", *M, 2, *N, 3, Ai, Aj, Ad, 8,
232 &info );
233 else
234 PB_Cchkmat( ctxt, "PCGEADD", "A", *N, 3, *M, 2, Ai, Aj, Ad, 8,
235 &info );
236 PB_Cchkmat( ctxt, "PCGEADD", "C", *M, 2, *N, 3, Ci, Cj, Cd, 13, &info );
237 }
238 if( info ) { PB_Cabort( ctxt, "PCGEADD", info ); return; }
239 #endif
240 /*
241 * Quick return if possible
242 */
243 if( ( *M == 0 ) || ( *N == 0 ) ||
244 ( ( ALPHA[REAL_PART] == ZERO && ALPHA[IMAG_PART] == ZERO ) &&
245 ( BETA [REAL_PART] == ONE && BETA [IMAG_PART] == ZERO ) ) )
246 return;
247 /*
248 * And when alpha is zero
249 */
250 if( ( ALPHA[REAL_PART] == ZERO ) && ( ALPHA[IMAG_PART] == ZERO ) )
251 {
252 if( ( BETA[REAL_PART] == ZERO ) && ( BETA[IMAG_PART] == ZERO ) )
253 {
254 PB_Cplapad( PB_Cctypeset(), ALL, NOCONJG, *M, *N, ((char *)BETA),
255 ((char *)BETA), ((char *) C), Ci, Cj, Cd );
256 }
257 else
258 {
259 PB_Cplascal( PB_Cctypeset(), ALL, NOCONJG, *M, *N, ((char *)BETA),
260 ((char * )C), Ci, Cj, Cd );
261 }
262 return;
263 }
264 /*
265 * Start the operations
266 */
267 /*
268 * This operation mainly involves point-to-point send and receive communication.
269 * There is therefore no particular BLACS topology to recommend. Still, one can
270 * choose the main loop direction in which the operands will be added. This
271 * selection is based on the current setting for the BLACS broadcast operations.
272 */
273 if( notran )
274 {
275 rtop = *PB_Ctop( &ctxt, BCAST, ROW, TOP_GET );
276 ctop = *PB_Ctop( &ctxt, BCAST, COLUMN, TOP_GET );
277
278 if( *M <= *N )
279 {
280 DirA = ( rtop == CTOP_DRING ? CBACKWARD : CFORWARD );
281 DirC = ( ctop == CTOP_DRING ? CBACKWARD : CFORWARD );
282 }
283 else
284 {
285 DirA = ( ctop == CTOP_DRING ? CBACKWARD : CFORWARD );
286 DirC = ( rtop == CTOP_DRING ? CBACKWARD : CFORWARD );
287 }
288 PB_Cpgeadd( PB_Cctypeset(), &DirA, &DirC, NOCONJG, *M, *N,
289 ((char *) ALPHA), ((char *) A), Ai, Aj, Ad,
290 ((char *) BETA), ((char *) C), Ci, Cj, Cd );
291 }
292 else if( TrA == CTRAN )
293 {
294 PB_Cptran( PB_Cctypeset(), NOCONJG, *M, *N, ((char *) ALPHA),
295 ((char *) A), Ai, Aj, Ad, ((char *) BETA), ((char *) C),
296 Ci, Cj, Cd );
297 }
298 else
299 {
300 PB_Cptran( PB_Cctypeset(), CONJG, *M, *N, ((char *) ALPHA),
301 ((char *) A), Ai, Aj, Ad, ((char *) BETA), ((char *) C),
302 Ci, Cj, Cd );
303 }
304 /*
305 * End of PCGEADD
306 */
307 }
308