[new-regalloc] Dataflow too slow...

[Daniel Berlin]

On Sun, 4 Feb 2001, Michael Hayes wrote:

> Geert Bosch writes:
>  > One of the things I'm stumbling on now is that df_rd_global_compute
>  > takes way too much time to allow me to bootstrap the Ada compiler.
>
> I used a simple worklist algorithm for this to get the ball rolling.
> The usual solution to impove the performance is to order the blocks
> with a depth first search.  This was on my todo list.

I did this as well, i forgot to mention.
I use flow_compute_depth_first_order to get the dfs ordering, and then
have it pick the first block on the worklist, in order of dfs order
IE
for (i=0; i < n_basic_blocks; i++)
  if (TEST_BIT (worklist, dfs_order[i])
     return dfs_order[i];

 >
> There are many other more esoteric algorithms in the literature which
> would be a nice self-contained project for someone to implement.
Yup.