Optimization Switches of the 64-Bit Compilers

Optimization Switches of the 64-Bit Compilers

In addition to the switches listed above, both the 64-bit Fortran and 64-bit C compilers support many more switches. These switches are used to control the types of optimizations the compilers perform. This section outlines the various optimizations that the 64-bit compilers can perform, and lists the switches used to control them. To get a summary of the flags and their values set the -LIST:=ON flag on the command line. For example:

%f77 -64 -O3 -mips4 -LIST:=ON foo.f

This creates a .L file which contains a summary of all the flags used in the compilation including the default values of flags not explicitly set on the command line.

The optimizations and switches fall into the following categories:

General Optimizations
Floating Point Optimizations
Miscellaneous Optimizations
Global Code Motion
Software Pipelining
Target Environment Issues

General Optimizations
Floating Point Optimizations
Miscellaneous Optimizations
Loop Unrolling Optimizations
Global Code Motion
Software Pipelining
Target Environment Issues
Data Alignment Options