---------- Forwarded message ----------
From: Sandeep Maram <[EMAIL PROTECTED]>
Date: Thu, Apr 10, 2008 at 11:57 AM
Subject: Re: Fusing two loops
To: Zdenek Dvorak <[EMAIL PROTECTED]>
Hi Zdenek,
I have written this function
/* The following function fuses two loops. */
void
fuse_loops (struct loop *loop_a, struct loop *loop_b)
{
debug_loop (loop_a, 10);
debug_loop (loop_b, 10);
block_stmt_iterator bsi_a = bsi_start (loop_a->header);
block_stmt_iterator bsi_b = bsi_last (loop_b->header);
bsi_move_before (&bsi_a, &bsi_b);
fprintf (stderr, " transferred one statement from loop %d to loop %d
", loop_a->num, loop_b->num);
debug_loop (loop_a, 10);
debug_loop (loop_b, 10);
cancel_loop_tree (loop_a);
}
It moved one statement from loop_a to loop_b. In the same way I must
tranfer all other statements too. I get a internal compiler error at "
cancel_loop_tree(loop_a); " . After transfering statemnts from loop_a
to loop_b I need to delete the loop_a from current_loops . How can we
do this?
Thanks,
Sandeep.
On Fri, Apr 4, 2008 at 7:31 PM, Zdenek Dvorak <[EMAIL PROTECTED]> wrote:
> Hi,
>
> > I am trying to fuse two loops in tree level. For that, I am trying to
> > transfer statements in the header of one loop to the header of the
> > other one.
> > The code " http://rafb.net/p/fha0IG57.html " contains the 2 loops.
> > After moving a statement from one BB to another BB, do I need to
> > update any other info?
>
> you will need to update SSA form; other than that, just using bsi_move_after
> to move the relevant statements should work.
>
>
> > I need to transfer all the statements of bb_6 to bb_3. Can any one
> > please tell me what is the exact procedure.
> > Can i simply use add_bb_to_loop() and add bb_6 to loop_1 ?
>
> No; in the case that you describe, moving the statements one by one is
> probably the simplest way (you could also move whole basic block, but
> it is more complicated, and since you still need to update SSA form,
> you would need to process the statements anyway).
>
> Zdenek
>
