HP Fortran Programmer Guide HP-UX 11i v1, HP-UX 11i v2, and HP-UX 11i v3 (B3908-90032,December 2012)

Controlling code generation for performance
For optimum performance, the executable program should consist of code that can take advantage
of the hardware features of the machine on which the program will run. If your program will run
on the same machine as you use to compile it, code generation is not an issue. By default, the HP
Fortran compiler generates code for the model of the machine on which you are running the
compiler.
However, if you are compiling on a different machine from the one on which the program will run,
you should use the +DAmodeloption to ensure that the compiler generates code based on the
target architecture. For information about using this option, see “Compiling for different PA-RISC
machines” on page 87.
104 Performance and optimization