ScaLAPACK 2.1  2.1 ScaLAPACK: Scalable Linear Algebra PACKage
BI_MringComb.c
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1 #include "Bdef.h"
2 void BI_MringComb(BLACSCONTEXT *ctxt, BLACBUFF *bp, BLACBUFF *bp2,
3  int N, VVFUNPTR Xvvop, int dest, int nrings)
4 {
5  void BI_Ssend(BLACSCONTEXT *, int, int, BLACBUFF *);
6  void BI_Srecv(BLACSCONTEXT *, int, int, BLACBUFF *);
7  void BI_MpathBS(BLACSCONTEXT *, BLACBUFF *, SDRVPTR, int);
8  void BI_MpathBR(BLACSCONTEXT *, BLACBUFF *, SDRVPTR, int, int);
9
10  int Np, Iam, msgid, i, inc, mysrc, mydest, Np_1;
11  int mydist, ringlen, myring;
12  int nearedge, faredge; /* edge closest and farthest from dest */
13  int REBS; /* Is result leave-on-all? */
14
15  Np = ctxt->scp->Np;
16  if (Np < 2) return;
17  Iam = ctxt->scp->Iam;
18  msgid = Mscopeid(ctxt);
19  if (REBS = (dest == -1)) dest = 0;
20
21  if (nrings > 0)
22  {
23  mydist = (Np + dest - Iam) % Np;
24  inc = 1;
25  }
26  else
27  {
28  mydist = (Np + Iam - dest) % Np;
29  inc = -1;
30  nrings = -nrings;
31  }
32  Np_1 = Np - 1;
33  if (nrings > Np_1) nrings = Np_1;
34
35 /*
36  * If I'm not the destination
37  */
38  if (Iam != dest)
39  {
40  ringlen = Np_1 / nrings;
41  myring = (mydist-1) / ringlen;
42  if (myring >= nrings) myring = nrings - 1;
43  nearedge = (myring*ringlen) + 1;
44  faredge = nearedge + ringlen - 1;
45  if (myring == nrings-1) faredge += Np_1 % nrings;
46  if (mydist == nearedge) mydest = dest;
47  else mydest = (Np + Iam + inc) % Np;
48  if (mydist != faredge)
49  {
50  BI_Srecv(ctxt, (Np + Iam - inc) % Np, msgid, bp2);
51  Xvvop(N, bp->Buff, bp2->Buff);
52  }
53  BI_Ssend(ctxt, mydest, msgid, bp);
54  if (REBS) BI_MpathBR(ctxt, bp, BI_Ssend, dest, nrings);
55  }
56 /*
57  * If I'm the destination process
58  */
59  else
60  {
61  if (!ctxt->TopsRepeat)
62  {
63  for(i=nrings; i; i--)
64  {
65  BI_Srecv(ctxt, BANYNODE, msgid, bp2);
66  Xvvop(N, bp->Buff, bp2->Buff);
67  }
68  }
69  else
70  {
71  ringlen = Np_1 / nrings;
72  if (inc == 1) mysrc = (Np + Iam - 1) % Np;
73  else mysrc = (Iam + 1) % Np;
74  for(i=nrings; i; i--)
75  {
76  BI_Srecv(ctxt, mysrc, msgid, bp2);
77  Xvvop(N, bp->Buff, bp2->Buff);
78  if (inc == 1) mysrc = (Np + mysrc - ringlen) % Np;
79  else mysrc = (mysrc + ringlen) % Np;
80  }
81  }
82  if (REBS) BI_MpathBS(ctxt, bp, BI_Ssend, nrings);
83  }
84 } /* end BI_MringComb */
bLaCsCoNtExT::TopsRepeat
int TopsRepeat
Definition: Bdef.h:27
BI_MpathBS
void BI_MpathBS(BLACSCONTEXT *ctxt, BLACBUFF *bp, SDRVPTR send, int npaths)
Definition: BI_MpathBS.c:3
bLaCbUfF::Buff
char * Buff
Definition: Bdef.h:56
BI_Ssend
void BI_Ssend(BLACSCONTEXT *ctxt, int dest, int msgid, BLACBUFF *bp)
Definition: BI_Ssend.c:3
BI_MpathBR
void BI_MpathBR(BLACSCONTEXT *ctxt, BLACBUFF *bp, SDRVPTR send, int src, int npaths)
Definition: BI_MpathBR.c:3
bLaCbUfF
Definition: Bdef.h:54
VVFUNPTR
void(* VVFUNPTR)(int, char *, char *)
Definition: Bdef.h:68
bLaCsScOpE::Iam
int Iam
Definition: Bdef.h:17
BI_MringComb
void BI_MringComb(BLACSCONTEXT *ctxt, BLACBUFF *bp, BLACBUFF *bp2, int N, VVFUNPTR Xvvop, int dest, int nrings)
Definition: BI_MringComb.c:2
Mscopeid
#define Mscopeid(ctxt)
Definition: Bdef.h:179
bLaCsCoNtExT
Definition: Bdef.h:23
SDRVPTR
void(* SDRVPTR)(BLACSCONTEXT *, int, int, BLACBUFF *)
Definition: Bdef.h:69
bLaCsCoNtExT::scp
BLACSSCOPE * scp
Definition: Bdef.h:26
Bdef.h
BI_Srecv
void BI_Srecv(BLACSCONTEXT *ctxt, int src, int msgid, BLACBUFF *bp)
Definition: BI_Srecv.c:3
bLaCsScOpE::Np
int Np
Definition: Bdef.h:17
BANYNODE
#define BANYNODE
Definition: Bdef.h:76