harmony-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Robin Garner <robin.gar...@anu.edu.au>
Subject Re: [DRLVM] MMTk vmmagic classes, can someone w/ compiler experience help me?
Date Thu, 15 Jun 2006 07:04:20 GMT
Robin Garner wrote:
> Weldon Washburn wrote:
>> All,
>>
>> I am hoping someone who has worked on compilers can actually do the
>> JIT modifications.  I don't have much experience in compilers.
>>
>> I am trying to get MMTk write barriers integrated into Harmony DRLVM.
>> I came up with the following scheme.  I don't know if it is correct.
>> It would be great if someone from the MMTk crowd looked at it.  If it
>> helps, I can also post this message on Jikes/MMTk mailing list.
>>
>> Build a shim between the DRLVM class loader and Jitrino.JET.  The shim
>> would contain a lookup table that would map _local_ variables of
>> specific types to int.  In particular, the shim would re-map local
>> variables of the below types to int:
>>
>> Address
>> Extent
>> Offset
>> Word
>>
>> The reason for the shim is to avoid modifying the class loader.  This
>> should reduce the maintenance burden.
>>
>> Java source code that creates objects of the above classes is a now a
>> problem.  For example, Java source code that does:
>>
>>     int xx = 33;
>>     Address a1 = new Address(xx);
>>
> MMTk never creates instances of the unboxed magic types, so this 
> shouldn't be a problem.
>
Oh, and 'int' is a bad choice, since it is always 32 bits.  These types 
should be whatever the natural word length of the target architecture is.

cheers

---------------------------------------------------------------------
Terms of use : http://incubator.apache.org/harmony/mailing.html
To unsubscribe, e-mail: harmony-dev-unsubscribe@incubator.apache.org
For additional commands, e-mail: harmony-dev-help@incubator.apache.org


Mime
View raw message