Re: PING: [PATCH] PR target/67215: -fno-plt needs improvements for x86

[Jiong Wang <jiong dot wang at foss dot arm dot com>]

On 27/10/15 11:37, H.J. Lu wrote:
> On Tue, Oct 27, 2015 at 4:20 AM, Bernd Schmidt <bschmidt@redhat.com> wrote:
> > On 10/19/2015 09:55 PM, H.J. Lu wrote:
> > >           * calls.c (prepare_call_address): Don't handle -fno-plt here.
> >
> > Is any other target using -fno-plt? If not, and if that's really just a
> aarch64 is the only target which checks -fno-plt from commit log below.
> I CCed the code author.  aarch64 may suffer from the same issue.

H.J,

  Thanks for the info.

  After a quick reading of the PR at 
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67215,
  I found the problem description is very x86 specific, I still don't 
understand what's
  wrong if we do the following transformation when -fno-plt specified 
on x86-74, thus I
  am not sure whether there is problem exist on aarch64. Can you please 
give more explanation?

  call    proc2@PLT

  ||
  V

  movq    proc2@GOTPCREL(%rip), %rax
  call    *%rax