[Soot-list] How can cancel other default optimization?

[Eric Bodden]

Hmmm, I don't really know. What particular differences in the bytecode
are you seeing?

I think that there are some last-minute optimizations that Soot always
runs, but it would help if you could give me some concrete examples so
that I could try to determine what's actually going on.

Eric

2008/11/11 Jian Xu <fightmyway at gmail.com>:
> Hi Eric:
> I find when I add my transformer to the "jap" pack, the target is still
> moving on. The problem is about "unused local eliminate". this options can
> disabled, but I wonder whether the other optimization will disturb the
> bytecode?
>
> On Mon, Nov 10, 2008 at 10:49 PM, Eric Bodden <eric.bodden at mail.mcgill.ca>
> wrote:
>>
>> Hi Jian.
>>
>> Yes, you are basically trying to shoot at a moving target, so it's
>> best to not shoot until the target isn't moving any more ;-)
>>
>> Try adding your transformer to the "jap" pack instead:
>>
>>        PackManager.v().getPack("jap").add(
>>                new Transform("jap.instrumenter", Mystrument.v()));
>>
>> The "jap" pack is executed after all optimizations and little to no
>> transformations should take place after it.
>>
>> Maybe that's good enough in your case.
>>
>> Eric
>>
>> 2008/11/10 Jian Xu <fightmyway at gmail.com>:
>> > Hi Eric:
>> > Thank you for your reply.
>> >
>> > I do instrumentation, and insert instrument one instruction into every
>> > ExceptionalBlockGraph's node --- Block.
>> >         PackManager.v().getPack("jtp").add(
>> >                 new Transform("jtp.instrumenter", Mystrument.v()));
>> >         soot.Main.main();
>> >
>> > when I implement my Mystrument, soot read body which is a parameter of
>> > "internalTransform(Body b, String phaseName, Map options)". I find the
>> > body
>> > is generated by javac and not have optimized. At last, soot create new
>> > optimized bytecode. Of course, this is the power of soot. because I
>> > insert
>> > instruction into every Block, but at last the new bytecode optimized the
>> > Block. The jimple code doesn't have any statement of that Block in the
>> > original bytecode, except my instrument instruction. So this instrument
>> > instruction is useless and strange.
>> >
>> > for example original code is
>> > Block 0:
>> > statement 1
>> > statement 2
>> >
>> > Block 1:
>> > statement 3
>> >
>> > Block 2:
>> > statement 4
>> >
>> > then do instrumentation and I expect the code generated at last is
>> > Block 0:
>> > statement 1
>> > statement 2
>> > my instruction0
>> >
>> > Block 1:
>> > statement 3
>> > my instruction1
>> >
>> > Block 2:
>> > statement 4
>> > my instruction2
>> >
>> > but actually
>> > Block 0:
>> > statement 1
>> > statement 2
>> > my instruction0
>> > my instruction1
>> >
>> > Block 1:
>> > statement 4
>> > my instruction2
>> >
>> > so all the Block index change. And the " my instruction1" in the actual
>> > code
>> > is useless. Is there a way to solve the problem?
>> >
>> > Now I reach my goal by changing the bytecode created by javac first
>> > using
>> > soot.
>> > So the original code above is like:
>> > Block 0:
>> > statement 1
>> > statement 2
>> >
>> > Block 1:
>> > statement 4
>> >
>> > the new code
>> > Block 0:
>> > statement 1
>> > statement 2
>> > my instruction0
>> >
>> > Block 1:
>> > statement 4
>> > my instruction1
>> >
>> > Then every "my instruction " is useful. But you know when there are too
>> > many
>> > bytecodes, this way is time consuming.
>> >
>> >
>> >
>> >
>> >
>> >
>> >
>> >
>> > On Sun, Nov 9, 2008 at 10:25 PM, Eric Bodden
>> > <eric.bodden at mail.mcgill.ca>
>> > wrote:
>> >>
>> >> Hi Jian.
>> >>
>> >> This came up on the list just recently. See here:
>> >>
>> >> http://www.sable.mcgill.ca/pipermail/soot-list/2008-October/002012.html
>> >>
>> >> In a nutshell, you can disable most but not all optimizations, using
>> >> phase options:
>> >> http://www.sable.mcgill.ca/soot/tutorial/phase/index.html
>> >>
>> >>
>> >> Eric
>> >>
>> >> 2008/11/9 Jian Xu <fightmyway at gmail.com>:
>> >> > Hi:
>> >> > I make instrument to bytecode, so I add my transfer object into "jtp"
>> >> > pack
>> >> > then call Soot.Main.main() in my main function. But I find the
>> >> > bytecode
>> >> > which generated by soot do more modification than my transfer object
>> >> > do.
>> >> > I
>> >> > know when I call Soot.Main.main(), Soot do more optimization besides
>> >> > what I
>> >> > want to. So is there one way to do my transfer only but don't do
>> >> > others?
>> >> >
>> >> > Regards
>> >> > Jan
>> >> >
>> >> > _______________________________________________
>> >> > Soot-list mailing list
>> >> > Soot-list at sable.mcgill.ca
>> >> > http://mailman.cs.mcgill.ca/mailman/listinfo/soot-list
>> >> >
>> >> >
>> >>
>> >>
>> >>
>> >> --
>> >> Eric Bodden
>> >> Sable Research Group, McGill University, Montréal, Canada
>> >> Got an interesting job offer? http://www.bodden.de/hire-me/
>> >
>> >
>>
>>
>>
>> --
>> Eric Bodden
>> Sable Research Group, McGill University, Montréal, Canada
>> Got an interesting job offer? http://www.bodden.de/hire-me/
>
>



-- 
Eric Bodden
Sable Research Group, McGill University, Montréal, Canada
Got an interesting job offer? http://www.bodden.de/hire-me/