harmony-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Egor Pasko <egor.pa...@gmail.com>
Subject Re: [drlvm][opt] what does 'irBuilderFlags.expandMemAddrs' mean?
Date Wed, 07 May 2008 09:51:59 GMT
On the 0x43D day of Apache Harmony Simon Chow wrote:
> Thank you all~
> so all the 'St*'s (such as StField, StStatic, StElem etc.) are translated
> into TauStInd or TauStRef instruction now?
> additionally, what is the exact meaning of 'Tau' prefix?

On Tau plz first take a look at recent discussions:
http://thread.gmane.org/gmane.comp.java.harmony.devel/32642/focus=33106

Exact meaning is that inst has a Tau prefix iff destination operand is a Tau operand.

> 
> Thanks
> 
> 2008/5/7 George Timoshenko <george.timoshenko@gmail.com>:
> 
> > expandMemAddr is true by default.
> > I am not sure if it wrorks correctly in the 'false' case.
> >
> > This flag is obsolet actually.
> > It should be removed.
> >
> >
> > Egor Pasko wrote:
> >
> > > On the 0x43C day of Apache Harmony Simon Chow wrote:
> > >
> > > > Hi all
> > > > I found this flag is frequently used when generating 'Store' related
> > > > instruction.
> > > > if it is set, makeMultiSrcInst is used, otherwise makeFieldAccessInst
> > > > is
> > > > used, is that right? and Why is that?
> > > >
> > >
> > > after "Lazy Resolution" feature has been implemented, you can safely
> > > assume expandMemAddrs is always true, otherwise it just does not
> > > work.
> > >
> > > true makes indirect loads by addresses
> > > false makes special instructions like ldfield
> > >
> > > I dunno why there were two ways to do the same thing for ages. Maybe
> > > true value helped memopt (so you do not have to teach it with ldfield
> > > stuff), not sure.
> > >
> > >
> >
> 
> 
> -- 
> From : Simon.Chow@Software School of Fudan University

-- 
Egor Pasko


Mime
View raw message