RFC: PATCH: Add -maddress-mode=short|long for x86

[Uros Bizjak]

On Mon, Mar 12, 2012 at 6:48 PM, H.J. Lu <hongjiu.lu@intel.com> wrote:

> Trunk can now use SImode or DImode for Pmode with -mx32.  Pmode == SImode
> will avoid many conversions from SImode to DImode:
>
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50797
>
> It will use 0x67 address size prefix instead.  This patch adds a new
> command line option, -maddress-mode=short|long, for x86.  Any comments?

I think this is good option, I as a developer will be able to
benchmark different approaches for new target with this flag.

> 2012-03-12  H.J. Lu  <hongjiu.lu@intel.com>
>
>        * config/i386/i386-opts.h (pmode): New.
>
>        * config/i386/i386.c (ix86_option_override_internal): Properly
>        check and set ix86_pmode.
>
>        * config/i386/i386.h (Pmode): Check ix86_pmode instead of
>        TARGET_64BIT.
>
>        * config/i386/i386.opt (maddress-mode=): New.
>
>        * doc/invoke.texi: Document -maddress-mode=short|long for x86.

Please refer to PR target/50797 in the ChangeLog.

The patch is technically OK for mainline, Joseph - can you please
review option stuff?

I have also added Gerald to CC, to check if everything is OK with
added documentation.

Thanks,
Uros.