Recommended practice: The use of the
likely attribute
is intended to allow implementations to optimize for
the case where paths of execution including it
are arbitrarily more likely
than any alternative path of execution
that does not include such an attribute on a statement or label
. The use of the
unlikely attribute
is intended to allow implementations to optimize for
the case where paths of execution including it
are arbitrarily more unlikely
than any alternative path of execution
that does not include such an attribute on a statement or label
. A path of execution includes a label
if and only if it contains a jump to that label
. [
Note 1:
Excessive usage of either of these attributes
is liable to result in performance degradation
. —
end note]