> However, various optimizer needs to know about this special tree node.

not really (not any more than they know about other tree codes that are
not interesting for them).

If we take an example of Jump Threading pass then it needs to  know
about this tree node and update it properly.

So, the passes that maniuplate loop structure need to know about
LOOP_HEADER and others do not need to worry about LOOP_HEADER.

Now, focusing on the passes that manipulate loop structure. Are these
pass responsible for fixing loop info or is it responsiblity of cleanup pass ?

-
Devang

Reply via email to