[PATCH] [RFC] PR target/52813 and target/11807

[Thomas Preudhomme]

Hi Christophe,

That PR was about a bug occuring when sp was clobbered so if it cannot
be clobbered anymore the whole commit (r242693) can be removed. Let me
check the original code that lead to the PR why it's clobbering sp
though.

Best regards,

Thomas
On Wed, 12 Dec 2018 at 09:43, Christophe Lyon
<christophe.lyon@linaro.org> wrote:
>
> On Tue, 11 Dec 2018 at 16:52, Richard Sandiford
> <richard.sandiford@arm.com> wrote:
> >
> > Dimitar Dimitrov <dimitar@dinux.eu> writes:
> > > On понеделник, 10 декември 2018 г. 11:21:53 EET Richard Sandiford wrote:
> > >> Dimitar Dimitrov <dimitar@dinux.eu> writes:
> > >> > I have tested this fix on x86_64 host, and found no regression in the C
> > >> > and C++ testsuites.  I'm marking this patch as RFC simply because I don't
> > >> > have experience with other architectures, and I don't have a setup to
> > >> > test all architectures supported by GCC.
> > >> >
> > >> > gcc/ChangeLog:
> > >> >
> > >> > 2018-12-07  Dimitar Dimitrov  <dimitar@dinux.eu>
> > >> >
> > >> >    * cfgexpand.c (asm_clobber_reg_is_valid): Also produce
> > >> >    error when stack pointer is clobbered.
> > >> >    (expand_asm_stmt): Refactor clobber check in separate function.
> > >> >
> > >> > gcc/testsuite/ChangeLog:
> > >> >
> > >> > 2018-12-07  Dimitar Dimitrov  <dimitar@dinux.eu>
> > >> >
> > >> >    * gcc.target/i386/pr52813.c: New test.
> > >> >
> > >> > Signed-off-by: Dimitar Dimitrov <dimitar@dinux.eu>
> > >>
> > >> LGTM.  Do you have a copyright assignment on file?  'Fraid this is
> > >> probably big enough to need one.
> > > Yes, I have copyright assignment.
> >
> > OK, great.  I went ahead and applied the patch.
> >
>
> Hi,
>
> This patch introduces a regression on arm:
> FAIL: gcc.target/arm/pr77904.c (test for excess errors)
> Excess errors:
> /gcc/testsuite/gcc.target/arm/pr77904.c:7:3: error: Stack Pointer
> register clobbered by 'sp' in 'asm'
>
> Indeed the testcase has an explicit:
>   __asm volatile ("" : : : "sp");
> which is now rejected.
>
> Thomas, is that mandatory to test your code to fix pr77904?
>
> Thanks,
>
> Christophe
>
> > Thanks,
> > Richard