This appendix contains the following sections:
This appendix lists and describes the options supported by Power Fortran. The default settings are satisfactory for most programs. However, you can alter the defaults to customize output.
Table 2-1 on page 11 summarizes the Power Fortran command-line options.In that table, the Reference column lists functional categories of the following options:
parallelization
general optimization
inlining and interprocedural analysis
advanced optimization
directive control
listing
The next three columns list the long names, short names, and default values of the options. Following the table is an explanation of each option, including the option's long and short names, its default, and, if applicable, the long and short names for the NO version of the option. Although the options are listed in uppercase letters, you can specify them in lowercase as well.
 | Note: You can replace many of the Power Fortran command-line options described in this chapter with in-code directives. |
This section alphabetically lists and defines the command-line options that uniquely affect Power Fortran.
The –concurrentize option, described in Table A-1, converts eligible loops to run in parallel.
Table A-1. concurrentize Option
Long Option Name | Short Option Name | Default Value |
|---|---|---|
–concurrentize | –c | –concurrentize |
See also “noconcurrentize”.
The –limit option, described in Table A-2, reduces Power Fortran processing time by limiting the amount of time Power Fortran can spend trying to determine whether a loop is safe to run in parallel.
Power Fortran estimates how much time is required to analyze each loop nest construct. If an outer loop looks like it would take too much time to analyze, Power Fortran ignores the outer loop and recursively visits the inner loops.
Larger limits often allow Power Fortran to generate parallel code for deeply nested loop structures that it might not otherwise be able to run safely in parallel. However, with larger limits Power Fortran can also take more time to analyze a program. (The limit does not correspond to the DO loop nest level. It is an estimate of the number of loop orderings that Power Fortran can generate from a loop nest.)
The –lines option, described in Table A-3, paginates the listing for printing.
Use this option to change the number of lines per page. Specifying –lines=0 paginates at subroutine boundaries.
The –listoptions option, described in Table A-4, specifies the information to include in the listing file (.l).
Long Option Name | Short Option Name | Default Value |
|---|---|---|
–listoptions=list | –lo=list | –listoptions=ol |
list consists of any combination of the following letters:
| c | Calling tree at the end of the program listing. | |
| i | Transformed program file annotated with line numbers in the source program. Error messages and debugging information can refer to the original source rather than the transformed source. This option is automatically specified. | |
| k | Power Fortran option used at the end of each program unit. | |
| l | Loop-by-loop optimization table. | |
| n | Program unit names, as processed, to the standard error file. This option is added automatically as part of an f77 –v compilation. | |
| o | Annotated listing of the original program. | |
| p | Processing performance statistics. | |
| s | Summary of optimization performed. | |
| t | Annotated listing of the transformed program. |
The –minconcurrent option, described in Table A-5, establishes the minimum amount of work needed inside the loop to make executing a loop in parallel profitable.
Table A-5. minconcurrent Option
Long Option Name | Short Option Name | Default Value |
|---|---|---|
–minconcurrent=n | –mc=n | 500 |
If the loop does not contain at least this much work, the loop will not be run in parallel. If the loop bounds are not constants, an IF clause will be automatically added to the DOACROSS directive generated by Power Fortran to test at run time whether sufficient work exists.
The value n is a count of the number of operations (for example, add, multiply, load, store) in the loop, multiplied by the number of times the loop is executed.
The –noconcurrentize option, described in Table A-6, prevents Power Fortran from converting loops to run in parallel.
Table A-6. noconcurrentize Option
Long Option Name | Short Option Name | Default Value |
|---|---|---|
–noconcurrentize | –nconc | none |
See also “concurrentize”.
The –noparallelio option, described in Table A-7, disables the parallelization of loops that contain I/O statements.
Table A-7. noparallelio Option
Long Option Name | Short Option Name | Default Value |
|---|---|---|
–noparallelio | –nopio | option off |
Use this option only on systems with parallel I/O capabilities or where I/O statements in loops are not executed.
See also “parallelio”.
The –parallelio option, described in Table A-8, enables the parallelization of loops that contain I/O statements.
Long Option Name | Short Option Name | Default Value |
|---|---|---|
–parallelio | –pio | option off |
Use this option only on systems with parallel I/O capabilities or where I/O statements in loops are not executed.
See also “noparallelio”.
The –sopt option, described in Table A-9, requests execution of the scalar optimizer.
Long Option Name | Short Option Name | Default Value |
|---|---|---|
–sopt[,option,...] | –sopt | option off |
The –sopt option passes these options to Power Fortran:
-pfa,-roundoff=0,-scalaropt=3,-optimize=5 |
The –suppress option, described in Table A-10, lets you disable individual classes of Power Fortran messages that are normally included in the listing (.l) file.
Long Option Name | Short Option Name | Default Value |
|---|---|---|
–suppress=list | –su=list | option off |
These messages range from syntax warnings and error messages to messages about the optimizations performed. list is of any combination of the following:
| d | data dependence | |
| e | syntax error | |
| l | information | |
| n | not able to run loop in parallel | |
| q | questions | |
| s | standard messages | |
| w | warning of syntax error (Power Fortran adds the –suppress=w option automatically if you specify the –w option to f77) |