The NEC manuals describe all options in detail. A short overview for the fortran compiler will be given here:
sxf90 [external opts] \
[-Wp "<preprocessor
options>"] \
[-Wf "<internal
options>"] \
[-Wl "<linker
options>"]
<files>
The most important external options are:
-C [ hopt | vopt | sopt | vsafe | ssafe | debug ]
They set the optimization level. Default is vopt (=
vector optimization). The letters v and s mean vector and scalar, resp.
hopt is the highest level of optimization and should be used
with care. Be sure to check your results! (The -O option is a NEC
internal option and not related to the parameter of the CRAY compiler.)
-EP oder -Ep
activates the C preprocessor for suffixes f and f90. (-EP creates a file with preprocessor output, -Ep not)
-ftrace
is used for detailed performance analysis.
-eC
tells the compiler to instrument the code with the ABC test (=Array Bounds Check). Optimization is turned off then.
-P[ auto | multi | openmp | stack | static ]
creates parallel code. Default is static (no parallel code, all variables are static). Parameter auto specifies that the automatic parallelizing function -similar to the CRAY autotasking- will be used. (see Parallelverarbeitung auf SX-6 )
creates compile-time output lists. The default value is -R0, which means no list output.
-Rn (n=0,1,2,3,4,5)
The iteration count is important for vectorization. The compiler makes an assumption depending on array dimensions in a do loop. If this is not possible in complex loops the default value (5000) is taken. This may be too small in some cases and should be increased to the maximum possible loopcount (further information in the manual, Programmer's Guide ...).
-Wf "-pvctl noassume loopcnt=n"The value of n should be bigger than the loop count of the largest loop in your program.