Re: [tree-ssa] Any good sources of documentation?

["Marty Hauff" <marty.hauff@rmit.edu.au>]

Diego,

Thanks for your response.  There was an query posted by Matthieu Moy on 5/4 regarding "Where can I get the output of the front-end".  In this query he asked if there was a moment in the compilation at which we can see the whole program in one single tree?  The response suggested trying cgraph_finalize_compilation_unit ().  From your response I am assuming that tree-ssa does not parse the _whole_ program into one huge tree but rather parses each function individually.  I understand that this strategy uses far less memory but could tree-ssa be modified to parse the whole program into a single tree and if so would it break it?

Specifically I am trying to use the compiler to give me information about what hardware resources would be most useful for a given application.  I can't use the mainline code because it converts to RTL (which is machine dependent) very early on and does most of its optimisations in the RTL.  Ideally I would like to receive an already optimised tree that can be analysed to deduce an ideal hardware architecture.  Do you think that tree-ssa is the tool for this?????

Oh and by the way, I will be attempting to walk on water shortly after accomplishing all this.....

Marty

>>> Diego Novillo <dnovillo@redhat.com> 19/05/03 23:23:14 >>>
On Mon, 2003-05-19 at 04:22, Marty Hauff wrote:

> I'm trying to find out how the tree-ssa branch performs its
> compilation and optimisation.  I've found the doxygen stuff on the web
> but I need something a bit higher level at this stage.
>
Most documentation is in the source code itself.  There is a high-level
description of the optimization process in the project page
(http://gcc.gnu.org/projects/tree-ssa/).  After the GCC summit next
week, I will post the tree SSA paper and slides in my home page.

> Specifically I am looking to find a point during compilation where the
> most optimisation has been done PRIOR to target specific processing
> having been started.
>
tree-optimize.c:optimize_function_tree()

>   The main gcc branch is no good to me because it only does things on
> a function by function basis.  According to the docs, tree-ssa
> processes the whole source _before_ generating rtl etc. (or have I got
> this wrong?)
> 
Both mainline and tree-ssa operate in the same way.  If you use
-funit-at-a-time, then compilation proceeds in call graph order.


Diego.