B.1.2 Converting Cray-Style Fortran Directives
Cray-style Fortran parallelization directives are identical to Sun-style except that the sentinel that identifies these directives is !MIC$. Also, the set of qualifier clauses on the !MIC$ DOALL is different.
Table B–4 OpenMP Equivalents for Cray-Style DOALL Qualifier Clauses|
Cray DOALL Clause |
OpenMP PARALLEL DO Equivalent Clauses |
|---|---|
|
SHARED(v1,v2,...) |
SHARED(v1,v2,...) |
|
PRIVATE(v1,v2,...) |
PRIVATE(v1,v2,...) |
|
AUTOSCOPE |
No equivalent. Scoping must be explicit, or with the DEFAULT clause, or with the __AUTO clause |
|
SAVELAST |
No exact equivalent. You can achieve the same effect by using lastprivate. |
|
MAXCPUS(n) |
num_threads(n). No exact equivalent. |
|
GUIDED |
schedule(guided, m) Default m is 1. |
|
SINGLE |
schedule(dynamic,1) |
|
CHUNKSIZE(n) |
schedule(dynamic,n) |
|
NUMCHUNKS(m) |
schedule(dynamic,n/m) where n is the number of iterations |
B.1.2.1 Issues Between Cray-Style Fortran Directives and OpenMP Directives
The differences are the same as for Sun-style directives, except that there is no equivalent for the Cray AUTOSCOPE.
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