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/* 
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 * -- High Performance Computing Linpack Benchmark (HPL)                
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 *    HPL - 2.0 - September 10, 2008                          
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 *    Antoine P. Petitet                                                
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 *    University of Tennessee, Knoxville                                
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 *    Innovative Computing Laboratory                                 
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 *    (C) Copyright 2000-2008 All Rights Reserved                       
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 *                                                                      
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 * -- Copyright notice and Licensing terms:                             
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 *                                                                      
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 * Redistribution  and  use in  source and binary forms, with or without
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 * modification, are  permitted provided  that the following  conditions
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 * are met:                                                             
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 *                                                                      
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 * 1. Redistributions  of  source  code  must retain the above copyright
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 * notice, this list of conditions and the following disclaimer.        
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 *                                                                      
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 * 2. Redistributions in binary form must reproduce  the above copyright
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 * notice, this list of conditions,  and the following disclaimer in the
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 * documentation and/or other materials provided with the distribution. 
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 *                                                                      
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 * 3. All  advertising  materials  mentioning  features  or  use of this
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 * software must display the following acknowledgement:                 
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 * This  product  includes  software  developed  at  the  University  of
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 * Tennessee, Knoxville, Innovative Computing Laboratory.             
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 *                                                                      
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 * 4. The name of the  University,  the name of the  Laboratory,  or the
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 * names  of  its  contributors  may  not  be used to endorse or promote
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 * products  derived   from   this  software  without  specific  written
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 * permission.                                                          
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 *                                                                      
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 * -- Disclaimer:                                                       
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 *                                                                      
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 * THIS  SOFTWARE  IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,  INCLUDING,  BUT NOT
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 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE UNIVERSITY
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 * OR  CONTRIBUTORS  BE  LIABLE FOR ANY  DIRECT,  INDIRECT,  INCIDENTAL,
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 * SPECIAL,  EXEMPLARY,  OR  CONSEQUENTIAL DAMAGES  (INCLUDING,  BUT NOT
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 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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 * DATA OR PROFITS; OR BUSINESS INTERRUPTION)  HOWEVER CAUSED AND ON ANY
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 * THEORY OF LIABILITY, WHETHER IN CONTRACT,  STRICT LIABILITY,  OR TORT
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 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
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 * ---------------------------------------------------------------------
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 */ 
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/*
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 * Include files
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 */
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#include "hpl.h"
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#ifdef STDC_HEADERS
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int HPL_indxg2p
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(
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   const int                        IG,
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   const int                        INB,
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   const int                        NB,
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   const int                        SRCPROC,
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   const int                        NPROCS
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)
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#else
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int HPL_indxg2p
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( IG, INB, NB, SRCPROC, NPROCS )
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   const int                        IG;
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   const int                        INB;
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   const int                        NB;
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   const int                        SRCPROC;
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   const int                        NPROCS;
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#endif
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{
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/* 
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 * Purpose
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 * =======
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 *
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 * HPL_indxg2p computes the process coordinate  which posseses the entry
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 * of a matrix specified by a global index IG.
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 *
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 * Arguments
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 * =========
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 *
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 * IG      (input)                       const int
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 *         On entry, IG specifies the global index of the matrix  entry.
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 *         IG must be at least zero.
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 *
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 * INB     (input)                       const int
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 *         On entry,  INB  specifies  the size of the first block of the
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 *         global matrix. INB must be at least one.
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 *
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 * NB      (input)                       const int
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 *         On entry,  NB specifies the blocking factor used to partition
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 *         and distribute the matrix A. NB must be larger than one.
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 *
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 * SRCPROC (input)                       const int
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 *         On entry,  SRCPROC  specifies  the coordinate of the  process
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 *         that possesses the first row or column of the matrix. SRCPROC
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 *         must be at least zero and strictly less than NPROCS.
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 *
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 * NPROCS  (input)                       const int
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 *         On entry,  NPROCS  specifies the total number of process rows
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 *         or columns over which the matrix is distributed.  NPROCS must
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 *         be at least one.
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 *
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 * ---------------------------------------------------------------------
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 */ 
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/*
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 * .. Local Variables ..
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 */
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   int                        proc;
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/* ..
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 * .. Executable Statements ..
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 */
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   if( ( IG < INB ) || ( SRCPROC == -1 ) || ( NPROCS == 1 ) )
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/*
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 * IG  belongs  to the first block,  or the data is not distributed,  or
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 * there is just one process in this dimension of the grid.
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 */
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      return( SRCPROC );
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/*
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 * Otherwise,  IG is in block 1 + ( IG - INB ) / NB. Add this to SRCPROC
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 * and take the NPROCS  modulo (definition of the block-cyclic data dis-
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 * tribution).
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 */
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   proc = SRCPROC + 1 + ( IG - INB ) / NB;
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   return( MPosMod( proc, NPROCS ) );
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/*
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 * End of HPL_indxg2p
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 */
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}