HP Fortran Programmer's Guide (March 2010)

Compiling and linking
Compiling with the f90 command
Chapter 2 73
+O[no]libcalls
invokes millicode versions of a number of frequently called intrinsic
functions; see Table on page 73. Millicode routines have very low call
overhead and provide no error-handling. Use this option to improve the
performance of selected library routines only when your program does not
depend upon exception-handling.
The default is +Onolibcalls at optimization levels 0 and 1; at optimization
level 2 or higher, the default is +Olibcalls.
+o[no]libmerrno
Enable [disable] support for errno in libm functions.
The default is +Onolibmerrno.
+O[no]loop_block
+O[no]loop_block enables or disables blocking of eligible loops for
improved cache performance. The +Onoloop_block option disables both
automatic and directive-specified loop blocking.
+O[no]loop_transform
2 - 99 Less aggressive inlining. The optimizer gives more
weight to compilation time and code size when
determining whether to inline.
= 1 Only inline if it reduces code size.
Table 2-11 Millicode versions of intrinsic functions
acos cos pow
asin exp sin
atan log tan
atan2 log10
Table 2-10 Values for the +Oinline_budget option (Continued)
Values for n Meaning