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/* Copyright (C) 2009-2012 CSC - IT Center for Science Ltd.
* Please see the accompanying LICENSE file for further information.
* Helper macro for threading */
#ifndef __THREADED_H
#define __THREADED_H
/*
* Partitions a range of indices among threads.
*
* n the number of elements in the range
* tn the number of threads
* tid thread id
* s start index
* e end index
*/
#define SHARE_WORK(n, tn, tid, s, e) do { \
int q = (n) / (tn); \
int r = (n) % (tn); /* 0 <= r < q */ \
*(s) = q * (tid); \
*(e) = q * ((tid) + 1); \
if (r > 0) { \
if (r > (tid)) { \
/* Assing this thread one element more. */ \
*(s) += (tid); \
*(e) += (tid) + 1; \
} else { \
*(s) += r; \
*(e) += r; \
} \
} \
} while (0)
#endif /* ! __THREADED_H */
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