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Re: regrename doesn't take HARD_REGNO_CALL_PART_CLOBBERED into account
- To: Bernd Schmidt <bernds at cambridge dot redhat dot com>
- Subject: Re: regrename doesn't take HARD_REGNO_CALL_PART_CLOBBERED into account
- From: Alexandre Oliva <aoliva at redhat dot com>
- Date: 20 Mar 2001 01:46:49 -0300
- Cc: <gcc-patches at gcc dot gnu dot org>
- Organization: GCC Team, Red Hat
- References: <Pine.LNX.4.30.0103191310030.1311-100000@host140.cambridge.redhat.com>
On Mar 19, 2001, Bernd Schmidt <bernds@cambridge.redhat.com> wrote:
> I'm really confused about this macro. How is the information it gives us
> different from CALL_USED_REGISTERS?
A register is part-clobbered if a value in the given mode isn't
guaranteed to be preserved across function calls, but values in
(typically narrower) modes are. Setting CALL_USED_REGISTERS to 1 for
a register should be equivalent to arranging for
HARD_REGNO_CALL_PART_CLOBBERED to return 1 for all modes.
--
Alexandre Oliva Enjoy Guarana', see http://www.ic.unicamp.br/~oliva/
Red Hat GCC Developer aoliva@{cygnus.com, redhat.com}
CS PhD student at IC-Unicamp oliva@{lsd.ic.unicamp.br, gnu.org}
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