The --opt_level=3 option (aliased as the -O3 option) instructs the compiler to perform file-level optimization. This is the default optimization level. You can use the --opt_level=3 option alone to perform general file-level optimization, or you can combine it with other options to perform more specific optimizations. The options listed in Table 3-1 work with --opt_level=3 to perform the indicated optimization:
| If You ... | Use this Option | See |
|---|---|---|
| Want to create an optimization information file | --gen_opt_level=n | Section 3.3.1 |
| Want to compile multiple source files | --program_level_compile | Section 3.4 |