3.4 Compiling a Program for Parallel Execution Using kapf

To compile a program for parallel execution using kapf , use the following commands depending on your version of DIGITAL UNIX as follows:

• DIGITAL UNIX Version 3.2:

  kapf -conc -cmp=myprog_mp.f myprog.f
  
  f77 myprog_mp.f -fast -tune host -automatic -call_shared \
  -lkmp_osf -threads
  

• DIGITAL UNIX Versions 4.0 and above:

  kapf -conc -cmp=myprog_mp.f myprog.f
  
  f77 myprog_mp.f -fast -tune host -automatic -call_shared \
  -lkmp_osfp10 -pthread
  

An explanation of the compiler and linker switches follows:

• -automatic - tells the compiler to allocate local variables on the run-time stack.

• -conc - tells KAP to restructure source code for parallel processing.

• -cmp - causes KAP to save the optimized source program under the file name of your choice. The kapf default is to name the optimized source file_name.cmp . Because the Fortran compiler will not process a file with the default extension of .cmp , you must override the default by using -cmp to rename the optimized source file_ name.cmp.f .

• -fast - tells the compiler to optimize for speed and to set the optimization level to -O4 . If you override the default and set the compiler optimization level to -O5 , you must also set the following KAP and compiler switches:
  -unroll=1 - KAP switch
  -notransform_loops - DEC Fortran compiler switch that turns off the compiler's loop transform capabilities

  See Section 4.5.21 for more information about the -unroll switch.

• -lkmp_osf - tells the linker to use the KAP parallel processing library for DIGITAL UNIX Version 3.2. The parallel processing library provides an interface to DECthreads. See Section 3.1 for more information.

• -lkmp_osfp10 - tells the linker to use the KAP parallel processing library for DIGITAL UNIX Versions 4.0 and above. The parallel processing library provides an interface to DECthreads. See Section 3.1 for more information.

• -call_shared - tells the linker to link against shared libraries. DIGITAL recommends that you use -call_shared ; however, in the case where you want to link your application with archive libraries, refer to Section 3.5.

• -pthread - tells the linker to use threadsafe versions of libraries, where they exist, and to include DIGITAL UNIX Versions 4.0 and above libpthread when linking the program. See Section 3.1 for more information.

• -threads - tells the linker to use threadsafe versions of libraries, where they exist, and to include DIGITAL UNIX Version 3.2 libpthreads when linking the program. See Section 3.1 for more information.

• -tune host - tells the compiler to optimize for the architecture of the host processor. Note that the DEC Fortran -tune host switch and the DIGITAL KAP for DEC Fortran -tune switch work independently and perform different optimizations. For information about the DIGITAL KAP for DEC Fortran -tune switch, see Section 4.1.7.

Note

When you use kapf to process a file, you must set the DEC Fortran compiler and linker switches appropriately. For this reason, DIGITAL recommends that you use kf77 whenever possible, as kf77 automatically sets the compiler and linker switches correctly.

Copyright © Digital Equipment Corporation. 1997. All Rights Reserved.