<s>
In	O
computer	B-General_Concept
science	I-General_Concept
,	O
an	O
enabling	B-General_Concept
transformation	I-General_Concept
is	O
a	O
compiler	B-Application
optimization	I-Application
that	O
increases	O
the	O
effectiveness	O
of	O
other	O
compiler	B-Application
optimizations	I-Application
.	O
</s>
<s>
Typical	O
enabling	B-General_Concept
transformations	I-General_Concept
include	O
:	O
</s>
<s>
Loop	O
skewing	O
:	O
By	O
"	O
skewing	O
"	O
the	O
logical	O
shape	O
of	O
an	O
array	O
,	O
this	O
loop	O
optimization	O
can	O
(	O
when	O
combined	O
with	O
loop	O
interchange	O
)	O
eliminate	O
loop-carried	B-Operating_System
dependencies	I-Operating_System
,	O
allowing	O
an	O
inner	O
loop	O
to	O
be	O
parallelized	O
.	O
</s>
<s>
Loop	O
unswitching	O
moves	O
loop	B-Application
invariants	I-Application
out	O
of	O
a	O
loop	O
,	O
reducing	O
the	O
number	O
of	O
conditional	O
branches	O
in	O
each	O
loop	O
.	O
</s>
