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Re: [PATCH] fix BZ 18116 - build failure on ppc64le: setcontext.S uses power6 mtfsf when not supported
- From: Steven Munroe <munroesj at linux dot vnet dot ibm dot comcom>
- To: Martin Sebor <msebor at redhat dot com>
- Cc: munroesj at linux dot vnet dot ibm dot com, GNU C Library <libc-alpha at sourceware dot org>
- Date: Fri, 20 Mar 2015 08:22:07 -0500
- Subject: Re: [PATCH] fix BZ 18116 - build failure on ppc64le: setcontext.S uses power6 mtfsf when not supported
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- Reply-to: munroesj at linux dot vnet dot ibm dot com
On Wed, 2015-03-18 at 10:52 -0600, Martin Sebor wrote:
> >> You mean around each of the instances, as in the attached patch,
> >> as opposed to around the whole #if/#else block? Would you mind
> >> explaining in what way you think it's more correct than the first
> >> patch (a single pair of .machine directives around the whole
> >> conditional block)?
> >>
> > I mean around each instance of mtfsf 0xff,fp0,1,0
> >
> > What you suggested is only correct and safe for IBM POWER hardware
> > Power6 and later. It is not safe or correct for powerpc64 chips from
> > other manufacturer that implement a subset of the PowerISA-2.05 (or
> > later).
>
> I suspect you've misread the changes in the first patch.
>
> The first and the third patches are equivalent and after
> preprocessing will result in the assembler seeing the
> exact same code, including directives, regardless of what
> the target cpu is.
>
The 3rd patch dated March 16th is good.
My response on March 17th was to answer your questions in the text.
Sorry I did not respond earlier but our IMAP server has been down for
the last 3 days.
Thanks