This is the mail archive of the
gdb-patches@sourceware.org
mailing list for the GDB project.
Re: [PATCH,Testsuite] Add .align 2 for labels on Thumb
On Thu, Aug 12, 2010 at 09:21:55PM +0800, Yao Qi wrote:
> On Thu, Aug 12, 2010 at 08:34:39AM -0400, Daniel Jacobowitz wrote:
> > On Thu, Aug 12, 2010 at 07:49:08PM +0800, Yao Qi wrote:
> > > In original test case, breakpoint is set on insn nop, while main
> > > branches to insn push, so breakpoint is not hit.
> > >
> > > 0000000a <func_loopfb_start>:
> > > a: bf00 nop
> > >
> > > 0000000c <func_loopfb>:
> > > c: b480 push {r7}
> > >
> > > I thought this nop is generated for alignment, so I added '.align 2'
> > > for label func_loopfb_start to force it to be equal to func_loopfb. I
> > > make a mistake here.
> > >
> > > I don't know why nop is generated on label func_loopfb_start, and once
> > > '.align 2' is added, nop is *not* generated, so failures go away by
> > > accident.
> >
> > Can you use func_loopfb instead of func_loopfb_start in the .S file?
> > Or, can you define func_loopfb_start as asm ("func_loopfb_start =
> > func_loopfb")?
> >
> > A third option is to address Mark's concern by using ".p2align 4"; I
> > believe that is 16-byte alignment on all platforms gas supports, and
> > this test probably requires gas in practice already.
>
> Yeah, update my patch by replacing '.align 2' with '.p2align 4'.
> Is that OK?
Looks fine to me. Mark, what do you think?
--
Daniel Jacobowitz
CodeSourcery