The mexp program is an old-SUIF pass that must be run before the MIPS code generator. It has two functions. If the output file is not specified, mexp.sf is used.
Procedure calls returning structures .
The first parameter is explicitly assigned the return structure address. Describe the actions of each debug level. N Set the debug level to N , where N is between 0 and 9, inclusive. The default debug level is 0. The FOR loops should always be expanded before running mexp.