Technical data

Compiler Commands [2]
code. -h zeroinc is the safer and slower option. This option is affected by the
-h scalarn option (see Section 2.13.2, page 23).
2.14 UNICOS/mk Specific Optimization Options
The following sections describe UNICOS/mk specific compiler options.
2.14.1 -h pipelinen (CC, cc commands)
Default option: -h pipeline0
(UNICOS/mk systems) The -h pipelinen option specifies two levels of
software pipelining; on and off. The following are the various software pipelining
levels and their types of operations:
n
Description
0 No pipelining. Default.
1 Conservative pipelining. Only safe operator reassociations are
performed. Numeric results obtained at this level do not differ
from results obtained at level 0.
2 Moderate pipelining. Same as pipeline1.
3 Aggressive pipelining. Same as pipeline1.
2.14.2 -h [no]unroll (CC, cc)
Default option: -h nounroll
(UNICOS/mk systems) The -h unroll option instructs the compiler to attempt
to unroll all loops generated by the compiler. This technique is intended to
increase single processor performance at the cost of increasing compile time and
executable size. To control unrolling of loops individually, use the unroll
directive. For more information on this directive and loop unrolling, see Section
3.10.10, page 98.
Note: On UNICOS systems, -h unroll is enabled at all times.
2.14.3 -h [no]jump (CC, cc Commands)
Default option: -h jump
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