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C $Header: /u/u3/gcmpack/MITgcm/verification/front_relax/code/CPP_EEOPTIONS.h,v 1.2 2001/02/04 14:38:52 cnh Exp $ |
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C $Name: $ |
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C |
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C /==========================================================\ |
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C | CPP_EEOPTIONS.h | |
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C |==========================================================| |
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C | C preprocessor "execution environment" supporting | |
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C | flags. Use this file to set flags controlling the | |
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C | execution environment in which a model runs - as opposed | |
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C | to the dynamical problem the model solves. | |
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C | Note: Many options are implemented with both compile time| |
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C | and run-time switches. This allows options to be | |
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C | removed altogether, made optional at run-time or | |
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C | to be permanently enabled. This convention helps | |
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C | with the data-dependence analysis performed by the | |
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C | adjoint model compiler. This data dependency | |
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C | analysis can be upset by runtime switches that it | |
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C | is unable to recoginise as being fixed for the | |
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C | duration of an integration. | |
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C | A reasonable way to use these flags is to | |
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C | set all options as selectable at runtime but then | |
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C | once an experimental configuration has been | |
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C | identified, rebuild the code with the appropriate | |
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C | options set at compile time. | |
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C \==========================================================/ |
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|
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#ifndef _CPP_EEOPTIONS_H_ |
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#define _CPP_EEOPTIONS_H_ |
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|
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C In general the following convention applies: |
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C ALLOW - indicates an feature will be included but it may |
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C CAN have a run-time flag to allow it to be switched |
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C on and off. |
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C If ALLOW or CAN directives are "undef'd" this generally |
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C means that the feature will not be available i.e. it |
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C will not be included in the compiled code and so no |
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C run-time option to use the feature will be available. |
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C |
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C ALWAYS - indicates the choice will be fixed at compile time |
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C so no run-time option will be present |
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|
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C Flag used to indicate whether Fortran formatted write |
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C and read are threadsafe. On SGI the routines can be thread |
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C safe, on Sun it is not possible - if you are unsure then |
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C undef this option. |
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#undef FMTFTN_IO_THREADSAFE |
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|
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C-- Control MPI based parallel processing |
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#undef ALLOW_USE_MPI |
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#undef ALWAYS_USE_MPI |
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|
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C-- Control use of communication that might overlap computation. |
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C Under MPI selects/deselects "non-blocking" sends and receives. |
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#define ALLOW_ASYNC_COMMUNICATION |
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#undef ALLOW_ASYNC_COMMUNICATION |
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#undef ALWAYS_USE_ASYNC_COMMUNICATION |
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C-- Control use of communication that is atomic to computation. |
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C Under MPI selects/deselects "blocking" sends and receives. |
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#define ALLOW_SYNC_COMMUNICATION |
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#undef ALWAYS_USE_SYNC_COMMUNICATION |
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|
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C-- Control use of JAM routines for Artic network |
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C These invoke optimized versions of "exchange" and "sum" that |
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C utilize the programmable aspect of Artic cards. |
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#undef LETS_MAKE_JAM |
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#undef JAM_WITH_TWO_PROCS_PER_NODE |
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|
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C-- Control storage of floating point operands |
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C On many systems it improves performance only to use |
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C 8-byte precision for time stepped variables. |
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C Constant in time terms ( geometric factors etc.. ) |
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C can use 4-byte precision, reducing memory utilisation and |
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C boosting performance because of a smaller working |
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C set size. However, on vector CRAY systems this degrades |
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C performance. |
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#define REAL4_IS_SLOW |
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|
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C-- Control use of "double" precision constants. |
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C Use D0 where it means REAL*8 but not where it means REAL*16 |
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#define D0 d0 |
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|
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C-- Control XY periodicity in processor to grid mappings |
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C Note: Model code does not need to know whether a domain is |
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C periodic because it has overlap regions for every box. |
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C Model assume that these values have been |
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C filled in some way. |
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#undef ALWAYS_PREVENT_X_PERIODICITY |
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#undef ALWAYS_PREVENT_Y_PERIODICITY |
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#define CAN_PREVENT_X_PERIODICITY |
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#define CAN_PREVENT_Y_PERIODICITY |
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|
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#endif /* _CPP_EEOPTIONS_H_ */ |
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|
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#include "CPP_EEMACROS.h" |