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Re: More flow cleanup
- To: Bernd Schmidt <crux at pool dot informatik dot rwth-aachen dot de>
- Subject: Re: More flow cleanup
- From: Jeffrey A Law <law at cygnus dot com>
- Date: Sat, 17 Oct 1998 02:38:59 -0600
- cc: egcs-patches at cygnus dot com
- Reply-To: law at cygnus dot com
In message <Pine.GSO.4.02A.9810151217260.7569-100000@holmes.informatik.rwth-a
achen.de>you write:
> Neither place would match the old behaviour exactly. Note that the old
> code gets its candidate pseudos from sometimes_max, which at that point
> still contains the state before the insn, but tests against OLD (which
> already contains the state after the insn). Thus, with the old code, any
> pseudo registers which are set during the call would not be affected (since
> OLD no longer contains them). If the new code is placed at the same point,
> it would additionally consider pseudos which are used in the call; if it
> is placed above, it does not consider the pseudos set in the call.
>
> As far as I know, call insns don't set pseudos; they set the hard return
> register and maybe the stack pointer. Thus, moving the code upwards before
> the update of OLD should have no effect.
Thanks for clarifying. I've installed your patch.
jeff