Slowdowns in code generated by GCC>=3.3

[Steven Bosscher]

On Tuesday 26 October 2004 22:09, Pablo Mejia wrote:
>     Steven> Now, the problem is that gcse and crossjumping may move
>     Steven> code in the block with the factored computed jump, so when
>     Steven> we later try to undo the factoring, we think it is too
>     Steven> expensive to do that.  We end up with lots and lots of
>     Steven> jumps to a single computed jump that is very difficult to
>     Steven> predict.
>
> I just lurk on this list, so feel free to ignore this comment...
>
> Perhaps it would be possible to mark the block with the factored
> computed jump in some way.

It is cumbersome to maintain such a marking.  I tried it at
first but it's hard to not lose the mark, and it's harder to
change all passes to be aware of such a block.

Gr.
Steven