D.1 General Fortran Directives

Format

C$PRAGMA keyword ( a [ , a ] … ) [ , keyword ( a [ , a ] … ) ] ,…

C$PRAGMA SUN keyword ( a [ , a ] … ) [ , keyword ( a [ , a ] … ) ] ,…

C$PRAGMA SPARC keyword ( a [ , a ] … ) [ , keyword ( a [ , a ] … ) ] ,…

Comment-indicator in column 1 may be c, C, !, or *. (We use C in these examples. f95 free-format must use !.)

C Directive

C$PRAGMA C(list)

Declares a list of names of external functions as C language routines. 

IGNORE_TKR Directive

C$PRAGMA IGNORE_TKR {name {, name} ...}

The compiler ignores the type, kind, and rank of the specified dummy argument names appearing in a generic procedure interface when resolving a specific call. 

UNROLL Directive

C$PRAGMA SUN UNROLL=n

Advises the compiler that the following loop can be unrolled to a length n.

WEAK Directive

C$PRAGMA WEAK(name[=name2])

Declares name to be a weak symbol, or an alias for name2.

OPT Directive

C$PRAGMA SUN OPT=n

Set optimization level for a subprogram to n.

PIPELOOP Directive

C$PRAGMA SUN PIPELOOP[=n]

Assert dependency in loop between iterations n apart.

PREFETCH Directives

C$PRAGMA SUN_PREFETCH_READ_ONCE (name)

C$PRAGMA SUN_PREFETCH_READ_MANY (name)

C$PRAGMA SUN_PREFETCH_WRITE_ONCE (name)

C$PRAGMA SUN_PREFETCH_WRITE_MANY (name)

Request compiler generate prefetch instructions for references to name. (Requires -xprefetch option, which is enabled by default. Prefetch directives can be disabled by compiling with —xprefetch=no. Target architecture must also support prefetch instructions, and the compiler optimization level must be set greater than —xO2.)

ASSUME Directives

C$PRAGMA [BEGIN} ASSUME (expression [,probability])

C$PRAGMA END ASSUME

Make assertions about conditions at certain points in the program that the compiler can assume are true.