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Re: [PATCH]: Implement must-def kill operand
On Oct 20, 2004, at 5:03 PM, Diego Novillo wrote:
On Wed, 2004-10-20 at 16:55, Daniel Berlin wrote:All told, including all necessary changes to DCE and comments, it's 89
lines of code added.
That will, in turn, mark the *feeders* of the phi as necessary,
they will be added to the worklist, and propagate_necessity doesn't
know that it doesn't need to mark the feeders unless they are phi
nodes, thus you will miss dead code being eliminated.
Ah, good point. Sigh. I think I'm about to ask you to just let the
regular renamer run and insert needed PHIs, but I agree that PHI node
churn should be avoided.
How much additional code are we talking about?
I factored what i could. :)
A good chunk of the
algorithm you described already exists in DCE. Can it be factored?