Table 29
Level | Level | Function |
+O[no]inline | +O3or higher | Enable [disable] inlining. |
|
| The default is +Oinline. |
|
|
|
+Oinline_level num | All | This option controls inlining |
|
| in fortran. The format for |
|
| num is N[.n], where num is |
|
| either an integral value from |
|
| 0 to 9 or a value with a |
|
| single decimal place from |
|
| 0.0 to 9.0. |
|
| For more information on this |
|
| option, see |
|
| F90((1))manpage. |
|
|
|
+O[no]libcalls | All | Substitute [do not substitute] |
|
| millicode versions of specific |
|
| intrinsics. The default is |
|
| +Olibcalls. |
|
|
|
+O[no]loop_block | +O3or higher | Loop blocking is a |
|
| combination of strip mining |
|
| and interchange that |
|
| improves data cache |
|
| locality. It is provided |
|
| primarily to deal with nested |
|
| loops that manipulate arrays |
|
| that are too large to fit into |
|
| the data cache. Under |
|
| certain circumstances, loop |
|
| blocking allows reuse of |
|
| these arrays by transforming |
|
| the loops that manipulate |
|
| them so that they manipulate |
|
| strips of the arrays that fit |
|
| into the cache. |
|
|
|
+O[no]loop_unroll=n | +O2or higher | Unroll [do not unroll] |
|
| program loops by a factor |
|
| of n. The default is |
|
| +Oloop_unroll=4. |
|
|
|
+O[no]loop_unroll_jam | +O3or higher | Loop |
|
| partially unrolling one or |
|
| more loops higher in the nest |
|
| than the innermost loop, and |
|
| fusing ("jamming") the |
|
| resulting loops back |
|
| together. This transformation |
|
| is primarily intended to |
|
| increase register reuse and |
|
| decrease memory loads and |
|
| stores per operation within |
|
| an iteration of a nested loop. |
|
|
|
+moduleoptimize | All | The compiler reads only |
|
| required information from a |
|
| module file. Optimized |
|
| module files are created by |
|
| discarding redundant |
|
| information while importing |
|
| the module file. In case of |
|
| nested modules or |
|
| hierarchical modules, the |
|
| compilation time and |
|
| memory requirement of |
Using options to control optimization | 95 |