This is the mail archive of the
gcc@gcc.gnu.org
mailing list for the GCC project.
Re: Work in progress: "Super Sib Calls"; opinions sought
- From: Jeff Law <law at porcupine dot slc dot redhat dot com>
- To: Fergus Henderson <fjh at cs dot mu dot OZ dot AU>
- Cc: Richard Henderson <rth at redhat dot com>, Andreas Bauer <baueran at in dot tum dot de>, gcc at gcc dot gnu dot org, pizka at in dot tum dot de, jason dot ozolins at anu dot edu dot au
- Date: Mon, 09 Sep 2002 11:13:34 -0600
- Subject: Re: Work in progress: "Super Sib Calls"; opinions sought
- Reply-to: law at redhat dot com
In message <20020909134920.GA26479@ceres.cs.mu.oz.au>, Fergus Henderson
writes:
>Actually there *is* code in sibcall.c to do such scanning (see
>uses_addressof() and sequence_uses_addressof() in sibcall.c). However,
>the test for frame_size in optimize_sibling_and_tail_recursive_calls()
>in sibcall.c makes this code currently redundant, I think.
>I don't understand why both are needed.
ADDRESSOF doesn't generate a stack slot until after CSE has completed. ie,
the existence of an ADDRESSOF expression will have zero effect on frame_size
until after CSE has completed and we purge ADDRESSOF expressions.
I'm pretty sure both checks are still necessary.
jeff