On Tue, Jul 29, 2025 at 02:36:28PM -0700, Andrew Pinski wrote:
> On Tue, Jul 29, 2025 at 6:58 AM Stefan Schulze Frielinghaus
> <stefa...@linux.ibm.com> wrote:
> >
> > From: Stefan Schulze Frielinghaus <stefa...@gcc.gnu.org>
> >
> > Targets hppa, m68k, pdp11, rx, sh, vax do not default to LRA. Since old
> > reload pass is still used, add option -mlra for those targets.
> >
> > For hppa, register 0 cannot be used as a general register. Therefore,
> > use temporary registers r20 and r21 instead.
> >
> > gcc/testsuite/ChangeLog:
> >
> > * gcc.dg/asm-hard-reg-error-4.c: Add option -mlra for targets
> > hppa, m68k, pdp11, rx, sh, vax. Use registers r20 and r21 for
> > hppa.
> > * gcc.dg/asm-hard-reg-error-5.c: Ditto.
> > ---
> > Verified via cross compilers for hppa64-linux-gnu, m68k-linux-gnu,
> > pdp11-aout, rx-elf, sh4eb-linux-gnu, vax-linux-gnu. Ok for mainline?
> >
> > gcc/testsuite/gcc.dg/asm-hard-reg-error-4.c | 15 ++++++++++++---
> > gcc/testsuite/gcc.dg/asm-hard-reg-error-5.c | 13 +++++++++++--
> > 2 files changed, 23 insertions(+), 5 deletions(-)
> >
> > diff --git a/gcc/testsuite/gcc.dg/asm-hard-reg-error-4.c
> > b/gcc/testsuite/gcc.dg/asm-hard-reg-error-4.c
> > index 465f24b1f71..e408f157dd3 100644
> > --- a/gcc/testsuite/gcc.dg/asm-hard-reg-error-4.c
> > +++ b/gcc/testsuite/gcc.dg/asm-hard-reg-error-4.c
> > @@ -1,21 +1,30 @@
> > /* { dg-do compile } */
> > +/* { dg-additional-options "-mlra" { target hppa*-*-* m68*-*-* pdp11-*-*
> > rx*-*-* sh*-*-* vax-*-* } } */
>
> Why not use just:
> /* { dg-additional-options "-mlra" { target { ! lra } } } */
I'm not too familiar with all the other targets. From the exp file:
"This must not be called (results in ERROR) for targets that don't do
register allocation, and therefore neither use nor don't use LRA."
So I probably need to exclude those targets then manually?
>
> Or limit the testcase to lra targets like:
> /* { dg-do compile { target lra } } */
I would prefer this since it seems hassle free. We loose some test
coverage for targets which default to old reload but this is acceptable
since both tests are kind of target independent and in the long run LRA
becomes the default anyway.
Cheers,
Stefan
>
> Hopefully the old reload goes away during GCC 16 ...
>
> Thanks,
> Andrew
>
> >
> > /* Verify output operands. */
> >
> > +#ifdef __hppa__
> > +# define R0 "20"
> > +# define R1 "21"
> > +#else
> > +# define R0 "0"
> > +# define R1 "1"
> > +#endif
> > +
> > int
> > test (void)
> > {
> > int x;
> > - register int y __asm__ ("0");
> > + register int y __asm__ (R0);
> >
> > /* Preserve status quo and don't error out. */
> > __asm__ ("" : "=r" (x), "=r" (x));
> >
> > /* Be more strict for hard register constraints and error out. */
> > - __asm__ ("" : "={0}" (x), "={1}" (x)); /* { dg-error "multiple outputs
> > to lvalue 'x'" } */
> > + __asm__ ("" : "={"R0"}" (x), "={"R1"}" (x)); /* { dg-error "multiple
> > outputs to lvalue 'x'" } */
> >
> > /* Still error out in case of a mixture. */
> > - __asm__ ("" : "=r" (x), "={1}" (x)); /* { dg-error "multiple outputs to
> > lvalue 'x'" } */
> > + __asm__ ("" : "=r" (x), "={"R1"}" (x)); /* { dg-error "multiple outputs
> > to lvalue 'x'" } */
> >
> > return x + y;
> > }
> > diff --git a/gcc/testsuite/gcc.dg/asm-hard-reg-error-5.c
> > b/gcc/testsuite/gcc.dg/asm-hard-reg-error-5.c
> > index 85398f04cc8..da5d24ad7f4 100644
> > --- a/gcc/testsuite/gcc.dg/asm-hard-reg-error-5.c
> > +++ b/gcc/testsuite/gcc.dg/asm-hard-reg-error-5.c
> > @@ -1,13 +1,22 @@
> > /* { dg-do compile } */
> > +/* { dg-additional-options "-mlra" { target hppa*-*-* m68*-*-* pdp11-*-*
> > rx*-*-* sh*-*-* vax-*-* } } */
> >
> > /* Test clobbers.
> > See asm-hard-reg-error-{2,3}.c for tests involving register pairs. */
> >
> > +#ifdef __hppa__
> > +# define R0 "20"
> > +# define R1 "21"
> > +#else
> > +# define R0 "0"
> > +# define R1 "1"
> > +#endif
> > +
> > int
> > test (void)
> > {
> > int x, y;
> > - __asm__ ("" : "={0}" (x), "={1}" (y) : : "1"); /* { dg-error "hard
> > register constraint for output 1 conflicts with 'asm' clobber list" } */
> > - __asm__ ("" : "={0}" (x) : "{0}" (y), "{1}" (y) : "1"); /* { dg-error
> > "hard register constraint for input 1 conflicts with 'asm' clobber list" }
> > */
> > + __asm__ ("" : "={"R0"}" (x), "={"R1"}" (y) : : R1); /* { dg-error "hard
> > register constraint for output 1 conflicts with 'asm' clobber list" } */
> > + __asm__ ("" : "={"R0"}" (x) : "{"R0"}" (y), "{"R1"}" (y) : R1); /* {
> > dg-error "hard register constraint for input 1 conflicts with 'asm' clobber
> > list" } */
> > return x + y;
> > }
> > --
> > 2.49.0
> >
