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Re: [tree-ssa] RFC: Making control flow more explicit


On Thu, 2003-08-07 at 17:27, Zdenek Dvorak wrote:

> I agree it is radical and great change.  But it has to be.  I cannot see
> how could you get to it in "natural progression" -- the changes you
> propose in this thread form about 20 lines of the patch that I am
> currently working on (that will unfortunately have about 10000).
>
You will have to break that out into independent pieces.  There is more
than one problem here.  Changing something like the way statements are
chained is orthogonal to exposing more control flow, for instance. 
Exposing more control flow allow us more liberty when doing certain
transformations.  Modifying the way statements are chained is purely a
compile time performance issue.  Both need to be tested and incorporated
separately.


> The patch so far would have somewhat drastic consequences:
> 1) I had to remove most of the cleanups in tree-cfg.c
>
This is precisely why we are doing evolutionary changes.  This, for
instance, is unacceptable.  The goal in these three months is to beat
mainline.  We cannot accept regressions of this nature.  Particulary if
these are changes that have been sitting in your local tree with almost
no exposure.

We could, however, move this to a sub-branch of tree-ssa to serve as a
staging branch for doing some of the more radical stuff you have in
mind.  We could move from that branch into tree-ssa, as they become more
stable.


Diego.


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