single (nosingle). STMicroelectronics PGI
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Chapter 20. Directives and Pragmas Reference
single (nosingle)
The pragma single directs the compiler not to implicitly convert float values to double non-prototyped functions. This can result in faster code if the program uses only float parameters.
Note
Since ANSI C specifies that floats must be converted to double, this pragma results in non-ANSI conforming code. Valid only for routine or global scope.
tp
• static - static local pointers are safe
In a file containing multiple functions, the command-line option –Msafeptr might be helpful for one function, but can’t be used because another function in the file would produce incorrect results. In such a file, the safeptr pragma, used with routine scope could improve performance and produce correct results.
You use the directive or pragma tp to specify one or more processor targets for which to generate code.
cpgi$ tp [target]...
Note
The tp directive or pragma can only be applied at the routine or global level. For more information
about these levels, refer to “Scope of C/C++ Pragmas and Command-Line Options,” on page 109 .
Refer to the PGI Workstation Release Notes for a list of targets that can be used as parameters to the tp directive.
unroll (nounroll)
The unroll directive or pragma enables loop unrolling while nounroll disables loop unrolling.
Note
The unroll directive or pragma has no effect on vectorized loops.
The directive or pragma takes arguments c and n.
• c
specifies that c
complete unrolling should be turned on or off.
• n
specifies that n (count) unrolling should be turned on or off. In addition, the following arguments may be added to the unroll directive:
In addition, the following arguments may be added to the unroll directive: c:v sets the threshold to which c
unrolling applies. v
is a constant; and a loop whose constant loop count isless than or equal to (<=) v is completely unrolled.
cpgi$ unroll = c:v
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