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Re: Renaming moutline-msabi-xlogues to mcall-ms2sysv-xlogues
- From: Segher Boessenkool <segher at kernel dot crashing dot org>
- To: Daniel Santos <daniel dot santos at pobox dot com>
- Cc: Sandra Loosemore <sandra at codesourcery dot com>, gcc <gcc at gcc dot gnu dot org>, Uros Bizjak <ubizjak at gmail dot com>, Jan Hubicka <hubicka at ucw dot cz>
- Date: Mon, 10 Apr 2017 02:52:00 -0500
- Subject: Re: Renaming moutline-msabi-xlogues to mcall-ms2sysv-xlogues
- Authentication-results: sourceware.org; auth=none
- References: <4c579a0b-b77a-45c9-0e4c-e492f3df3859@pobox.com>
On Sun, Apr 09, 2017 at 03:52:30PM -0500, Daniel Santos wrote:
> So I've been browsing through the gcc docs for other archs and
> noticed that they all use different terminology for their options that
> call or jump to stubs as a substitute for emitting inline saves &
> restores for registers.
>
> ARC: -mno-millicode
> AVR: -mcall-prologues
> V850: -mno-prolog-function(enabled by default)
>
> I think that PowerPC/rs6000 does this without an option (or maybe in -Os?).
The rs6000 ports determines what to do in function rs6000_savres_strategy.
Whether or not to do inline saves is different per kind of registers
(integer, float, vector), per ABI, and depends on other factors as well:
we always inline if it is just as small, we always inline if the outline
routines wouldn't work, and indeed for some ABIs we inline unless -Os
was used. There are some more considerations.
But yes, there is no option to force different code generation. This
is a good thing.
Segher