Actually, we are targeting at x86 platform :) IPF is not concerned until now. I am sorry that I did not make this clear before. Now we just plan to enhance OPT using Open64 only for loops and other computation-intensive sections. Does it have some opportunities for performance improving? As you said, code motion and prefetch optimizations is more helpful in C compilers, and what is the advantaging we can take using JIT compiler? profiling? and? I have little experience here.
And I have not tried DRLVM on IPF yet... Thanks On 17 Jan 2008 15:41:08 +0300, Egor Pasko <[EMAIL PROTECTED]> wrote: > > On the 0x3CE day of Apache Harmony Simon Chow wrote: > > On 17 Jan 2008 13:31:05 +0300, Egor Pasko <[EMAIL PROTECTED]> wrote: > > > > > > On the 0x3CE day of Apache Harmony Simon Chow wrote: > > > > On 17 Jan 2008 11:08:54 +0300, Egor Pasko <[EMAIL PROTECTED]> > wrote: > > > > > > > > > > On the 0x3CD day of Apache Harmony Simon Chow wrote: > > > > > > I am studying OPT in jitrino. For understanding the process of > > > building > > > > > CFG, > > > > > > I have read some code of JavaByteCodeTranslator. > > > > > > In the constructor of JavaByteCodeTranslator, there is an > additional > > > > > pass > > > > > > named JavaLabelPrepass, > > > > > > I would like to ask what is the exact purpose of this pass? > > > > > > > > > > the purpose is to mark basic blocks and inference stack variables > and > > > > > local variables with their types. > > > > > > > > > > This information goes to the input of JavaByteCodeTranslator, > which in > > > > > single pass goes through each bytecode instruction and converts it > to > > > > > operand-based representation from the stack-based in bytecode. > > > > > > > > > > The problem is a little tricky (with variable merging logic) and > > > > > current design is poor. > > > > > > > > > > > Besides this, It is seems that the translator part will be > refined, > > > > > which I > > > > > > saw in the wiki. Has it already been done in the current > version? > > > > > > Thanks! > > > > > > > > > > no, translator is not refined, low priority task. > > > > > > > > > > Why do you study the process of building CFG? If you want to do > > > > > something with it, I would suggest to try some other place since > all > > > > > JIT people here will agree that debugging JavalabelPrepass is > > > > > brain-damaging. > > > > > > > > > > > > Thank! > > > > I am doing a project for combining static compiler with dynamic > > > compilation > > > > environment (jitrino.OPT) > > > > As first step, now I am planning to translate the Harmony IR to > WHIRL. > > > > > > hm, do you have a kind of draft design document on how you want to do > > > this? ..probably Harmony gurus can give some valuable input having > > > read this doc. > > > > > > There is no document for this yet, but I will write one in the next few > days > > after having a discussion with others in my group. > > Our static compilation platform is Open64, some of my teammates are > working > > on it. > > just to make sure.. is the primary goal to replace/enhance Jitrino.OPT > on IPF machines? Oh, those itanics.. > > > I only have a little understanding of jitrino.OPT. > > For achieving higher performance, which part or phases of jitrino.OPTcould > > be refined or replaced by Open64 optimization? > > Could you give me some suggestion? > > I am afraid I am not familiar with Open64 at all, and there are > concerns using a mix of Jitrino.OPT and Open64 since the latter is > licensed under GPL. So, do not show me their code :) > > Jitrino.OPT/IPF is rather immature/experimental/untested/etc. So, if > using Jitrino.OPT on IPF consider throwing away the code generator > (but take care about generating the right calling convention and > VM-related stuff like threading) > > As for the High-level optimizations, I do not know, where Open64 is > better, maybe Xiaofeng knows? :) > > I may try to forsee something: Fortran & C compilers have more freedom > for code motion and prefetch optimizations than a Java JIT compiler > (which has a more dynamic nature), so, when ported to Java realities a > C compiler is likely to behave not very cool. > > I would suggest you to enhance Jitrino IPF codegenerator in > if-conversion and register allocation, that looks like more > interesting and performance-beneficial. However, I am not sure if it > suits you good as a subject of research. > > Did you try running DRLVM on IPF? Does it work? Does it even compile? > > > By the way, This idea is original from Xiaofeng :) > > > > Thank you every much! > > > > > But I can not find more information for the CFG structure in > jitrino.OPT, > > > > which leads me to read the code in translation part. :( > > > > Any advice for this? > > > > > > there is no complete reference guide for HIR instructions yet. Once I > > > gave advice on this: > > > > > > http://article.gmane.org/gmane.comp.java.harmony.devel/24474/ > > > > > > feel free to ask specific questions on CFG and instructions :) > > > > > > -- > > > Egor Pasko > > > > > > > > > > > > -- > > From : [EMAIL PROTECTED] School of Fudan University > > -- > Egor Pasko > > -- >From : [EMAIL PROTECTED] School of Fudan University
