<s>
Trace	B-Application
scheduling	I-Application
is	O
an	O
optimization	B-Application
technique	O
developed	O
by	O
Josh	O
Fisher	O
used	O
in	O
compilers	B-Language
for	O
computer	B-Application
programs	I-Application
.	O
</s>
<s>
A	O
compiler	B-Language
often	O
can	O
,	O
by	O
rearranging	O
its	O
generated	O
machine	B-Language
instructions	I-Language
for	O
faster	O
execution	O
,	O
improve	O
program	O
performance	O
.	O
</s>
<s>
It	O
increases	O
ILP	O
(	O
Instruction	B-Operating_System
Level	I-Operating_System
Parallelism	I-Operating_System
)	O
along	O
the	O
important	O
execution	O
path	O
by	O
statically	O
predicting	O
frequent	O
execution	O
path	O
.	O
</s>
<s>
Trace	B-Application
scheduling	I-Application
is	O
one	O
of	O
many	O
known	O
techniques	O
for	O
doing	O
so	O
.	O
</s>
<s>
Trace	B-Application
scheduling	I-Application
uses	O
a	O
basic	O
block	O
scheduling	O
method	O
to	O
schedule	O
the	O
instructions	O
in	O
each	O
entire	O
trace	O
,	O
beginning	O
with	O
the	O
trace	O
with	O
the	O
highest	O
frequency	O
.	O
</s>
<s>
It	O
then	O
adds	O
compensation	O
code	O
at	O
the	O
entry	O
and	O
exit	O
of	O
each	O
trace	O
to	O
compensate	O
for	O
any	O
effects	O
that	O
out-of-order	B-General_Concept
execution	I-General_Concept
may	O
have	O
had	O
.	O
</s>
<s>
Trace	B-Application
scheduling	I-Application
was	O
originally	O
developed	O
for	O
Very	B-General_Concept
Long	I-General_Concept
Instruction	I-General_Concept
Word	I-General_Concept
,	O
or	O
VLIW	B-General_Concept
machines	O
,	O
and	O
is	O
a	O
form	O
of	O
global	O
code	O
motion	O
.	O
</s>
<s>
It	O
works	O
by	O
converting	O
a	O
loop	O
to	O
long	O
straight-line	O
code	O
sequence	O
using	O
loop	B-Operating_System
unrolling	I-Operating_System
and	O
static	O
branch	B-General_Concept
prediction	I-General_Concept
.	O
</s>
