Re: [lno] [patch] vectorization with unknown loop bound

[Devang Patel <dpatel at apple dot com>]

On May 18, 2004, at 3:12 AM, Olga Golovanevsky wrote:

> On May 17, 2004, at 18:01 PM, Devang Patel wrote:
>
> > On May 17, 2004, at 7:10 AM, Olga Golovanevsky wrote:
>
> > > I used some static functions from tree-ssa-loop-manip.c and
> > > cfgloopmanip.c, as well the function force_gimple_operand() from
> > > tree-ssa-loop-ivopts.c, so I changed these functions to non-static.
> > > Alternatively it was possible to make this loop transformation
> > > generic, that is a question whether it is worth doing.
>
> > If tree_ssa_loop_version () is used then some of the code
> > duplication can be avoided. But it can be done later.
>
> How would you suggest to use tree_ssa_loop_version () function?
>
> I looked at it before starting implementation also as at
> tree-duplicate-loop-to-header-edge () and
> duplicate-loop-to-header-edge ().
>
> In my understanding, later two function in general
> do the following:
>       - sequentially concatenate basic blocks of loop
> a given number of times
>       - straiten loop latch edges in order to generate one loop
>       - update ssa info (phis, names,...) of loop copies

tree_ssa_loop_version () uses loopify ()
loopify () uses tree_duplicate_loop_to_header_edge ()
tree_duplicate_loop_to_header_edge () uses 
duplicate_loop_to_header_edge ()

tree_duplicate_loop_to_header_edge () handles copying basic blocks
and fixing phis. If you can use it directly and write generic
transformation, as Zdenek suggested, then lot of code duplication can
be avoided.

--
Devang