[LLVMdev] GCC3.5 tree-ssa

[Yueqiang]

Does LLVM called the pthread directly?
and what time do you plan to release Java front end?

I'll try this.

----- Original Message ----- 
From: "Chris Lattner" <sabre at nondot.org>
To: "yue" <qiangyue at ict.ac.cn>
Cc: <llvmdev at cs.uiuc.edu>
Sent: Wednesday, December 24, 2003 12:47 PM
Subject: Re: [LLVMdev] GCC3.5 tree-ssa


> On Wed, 24 Dec 2003, yue wrote:
> 
> > we work on distribute software development, most programs are wroten in
> > java.
> > but the running speed of that is slowly,  it requires thread library to
> > support, you know.
> 
> I'm not sure exactly what you mean here.  LLVM does not currently have a
> Java front-end, though there is one in development.  Thread support should
> not be a problem, you can make pthreads calls just like you can with any
> other compiler.
> 
> I'm probably missing your point, can you restate it?
> 
> -Chris
> 
> > >On Wed, 24 Dec 2003, yue wrote:
> > >
> > >
> > >
> > >>why doesn't llvm transfer bytecode to RTL form? I mean the
> > >>cross-platform compile in GCC. Could LLVM do that?
> > >>
> > >>
> > >
> > >Sure, it would be a realtively straight-forward (but large and hard to get
> > >right, if you're not a GCC expert), project to build an LLVM front-end for
> > >GCC.  This would allow you to effectively use LLVM as a mid-level
> > >representation for GCC, and would allow you to use all of the GCC
> > >back-ends with LLVM.
> > >
> > >However, note that LLVM already does have a C backend, which allows you to
> > >interface the LLVM optimizer to GCC or any other platform compiler.  This
> > >effectively gives you most of the advantages of a real "RTL backend", with
> > >the added advantage that we support the Intel, Sun, SGI, etc compilers as
> > >well (at least in theory, we have only tried compiling the CBE output with
> > >the GCC and Intel compilers).  Also "C" is a very stable interface
> > >language, where the RTL interfaces and APIs are constantly changing.  The
> > >one advantage an RTL backend would have over the C backend is speed of
> > >compilation.
> > >
> > >
> > >
> > >>maybe tree-ssa also create the representation with a testual format if
> > >>needed. is it very difficalt? I want to know.
> > >>
> > >>
> > >
> > >There are _very strong_ political reasons that will prevent this from
> > >happening any time in the near future.  I suggest that you ask on the GCC
> > >list if you want more details.  All tree-ssa supports are some debugging
> > >dumps, which do not contain all of the information needed for compilation.
> > >
> > >
> > >
> > >>BWT: if we port pthread library to llvm, what do we consider at first?
> > >>
> > >>
> > >
> > >I'm not sure exactly what you mean.  If it's written in C, you should be
> > >able to just compile it with LLVM as you would any other program or
> > >library.  Have you run into a problem or bug?
> > >
> > >-Chris
> > >
> > >
> > >
> > >
> > >>Chris Lattner wrote:
> > >>
> > >>
> > >>
> > >>>On Wed, 24 Dec 2003, yue wrote:
> > >>>
> > >>>
> > >>>
> > >>>
> > >>>>what difference is between gcc3.5 tree-ssa and llvm?
> > >>>>
> > >>>>
> > >>>>
> > >>>>
> > >>>They are completely different projects.  The short version is that LLVM is
> > >>>more mature and stable than tree-ssa is, LLVM supports interprocedural and
> > >>>runtime optimization, and LLVM has a well defined intermediate
> > >>>representation with a textual format.  On the other hand tree-ssa may be a
> > >>>part of GCC 3.5 someday once it has stabilized and enough bugs have been
> > >>>fixed.  Oh, LLVM is written in C++ and tree-ssa is written in C.
> > >>>
> > >>>If there is something more specific you want to know, please ask.  It's
> > >>>very much the difference between apples and oranges.
> > >>>
> > >>>-Chris
> > >>>
> > >>>
> > >>>
> > >>>
> > >>>
> > >>
> > >>
> > >
> > >-Chris
> > >
> > >
> > >
> >
> >
> 
> -Chris
> 
> -- 
> http://llvm.cs.uiuc.edu/
> http://www.nondot.org/~sabre/Projects/
> 
>