<s>
In	O
computer	O
science	O
,	O
a	O
program	B-Operating_System
dependence	I-Operating_System
graph	I-Operating_System
(	O
PDG	O
)	O
is	O
a	O
representation	O
,	O
using	O
graph	O
notation	O
,	O
that	O
makes	O
data	B-Operating_System
dependencies	I-Operating_System
and	O
control	O
dependencies	O
explicit	O
.	O
</s>
<s>
These	O
dependencies	O
are	O
used	O
during	O
dependence	O
analysis	O
in	O
optimizing	B-Application
compilers	I-Application
to	O
make	O
transformations	O
so	O
that	O
multiple	O
cores	O
are	O
used	O
,	O
and	O
parallelism	O
is	O
improved	O
.	O
</s>
