@deftypefn {Target Hook} bool IS_COSTLY_DEPENDENCE (rtx @var{insn1}, rtx @var{insn2}, rtx @var{dep_link}, int @var{dep_cost}, int @var{distance})
This hook is used to define which dependences are considered costly by
-the target, so costly that it is not advisable to schedule the insns that
+the target, so costly that it is not advisable to schedule the insns that
are involved in the dependence too close to one another. The parameters
-to this hook are as follows: The second parameter @var{insn2} is dependent
-upon the first parameter @var{insn1}. The dependence between @var{insn1}
-and @var{insn2} is represented by the third parameter @var{dep_link}. The
-fourth parameter @var{cost} is the cost of the dependence, and the fifth
-parameter @var{distance} is the distance in cycles between the two insns.
+to this hook are as follows: The second parameter @var{insn2} is dependent
+upon the first parameter @var{insn1}. The dependence between @var{insn1}
+and @var{insn2} is represented by the third parameter @var{dep_link}. The
+fourth parameter @var{cost} is the cost of the dependence, and the fifth
+parameter @var{distance} is the distance in cycles between the two insns.
The hook returns @code{true} if considering the distance between the two
insns the dependence between them is considered costly by the target,
and @code{false} otherwise.
Defining this hook can be useful in multiple-issue out-of-order machines,
-where (a) it's practically hopeless to predict the actual data/resource
+where (a) it's practically hopeless to predict the actual data/resource
delays, however: (b) there's a better chance to predict the actual grouping
-that will be formed, and (c) correctly emulating the grouping can be very
+that will be formed, and (c) correctly emulating the grouping can be very
important. In such targets one may want to allow issuing dependent insns
-closer to one another - i.e, closer than the dependence distance; however,
+closer to one another - i.e, closer than the dependence distance; however,
not in cases of "costly dependences", which this hooks allows to define.
@end deftypefn
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