Re: [PATCH v1] x86: Fix missing __wmemcmp def for disable-multiarch build

[Noah Goldstein <goldstein.w.n@gmail.com>]

On Tue, Apr 19, 2022 at 6:42 PM H.J. Lu <hjl.tools@gmail.com> wrote:
>
> On Tue, Apr 19, 2022 at 4:40 PM Noah Goldstein <goldstein.w.n@gmail.com> wrote:
> >
> > On Tue, Apr 19, 2022 at 6:36 PM H.J. Lu <hjl.tools@gmail.com> wrote:
> > >
> > > On Tue, Apr 19, 2022 at 3:55 PM Noah Goldstein <goldstein.w.n@gmail.com> wrote:
> > > >
> > > > commit 8804157ad9da39631703b92315460808eac86b0c
> > > > Author: Noah Goldstein <goldstein.w.n@gmail.com>
> > > > Date:   Fri Apr 15 12:27:59 2022 -0500
> > > >
> > > >     x86: Optimize memcmp SSE2 in memcmp.S
> > > >
> > > > Only defined wmemcmp and missed __wmemcmp. This commit fixes that by
> > > > defining __wmemcmp and setting wmemcmp as a weak alias to __wmemcmp.
> > > >
> > > > Both multiarch and disable-multiarch builds succeed and full xchecks
> > > > pass.
> > > > ---
> > > >  sysdeps/x86_64/multiarch/wmemcmp-sse2.S | 8 +++++---
> > > >  sysdeps/x86_64/wmemcmp.S                | 6 ++++--
> > > >  2 files changed, 9 insertions(+), 5 deletions(-)
> > > >
> > > > diff --git a/sysdeps/x86_64/multiarch/wmemcmp-sse2.S b/sysdeps/x86_64/multiarch/wmemcmp-sse2.S
> > > > index 57be1c446e..92d6819cb3 100644
> > > > --- a/sysdeps/x86_64/multiarch/wmemcmp-sse2.S
> > > > +++ b/sysdeps/x86_64/multiarch/wmemcmp-sse2.S
> > > > @@ -16,10 +16,12 @@
> > > >     License along with the GNU C Library; if not, see
> > > >     <https://www.gnu.org/licenses/>.  */
> > > >
> > > > +#define USE_AS_WMEMCMP 1
> > > >  #if IS_IN (libc)
> > >
> > > Do we need to check "IS_IN (libc)" here?
> >
> > I'm not sure. Was essentially copying the existing memcmpeq code
> > for this:
> > https://sourceware.org/git/?p=glibc.git;a=blobdiff;f=sysdeps/x86_64/multiarch/memcmpeq-sse2.S;h=de7f5a7525ab41ea42ea581c6981ced63f8be976;hp=b80a29d4b05bd7401d16afdbeee96403480953d2;hb=a5659cf27d3ce6101c1632715d18ab6321755340;hpb=7a06be051c01b4325927efab5b4e4280bb4a5a42
>
> Can you follow wmemchr-sse2.S instead?

Fixed in v2.


>
> > >
> > > >  # define MEMCMP        __wmemcmp_sse2
> > > > +# include "memcmp-sse2.S"
> > > >  #else
> > > > -# define MEMCMP        wmemcmp
> > > > +# define MEMCMP        __wmemcmp
> > > > +# include "../memcmp.S"
> > > > +weak_alias (__wmemcmp, wmemcmp)
> > > >  #endif
> > > > -#define USE_AS_WMEMCMP 1
> > > > -#include "memcmp-sse2.S"
> > > > diff --git a/sysdeps/x86_64/wmemcmp.S b/sysdeps/x86_64/wmemcmp.S
> > > > index 032f389158..8bd3cf80db 100644
> > > > --- a/sysdeps/x86_64/wmemcmp.S
> > > > +++ b/sysdeps/x86_64/wmemcmp.S
> > > > @@ -16,6 +16,8 @@
> > > >     License along with the GNU C Library; if not, see
> > > >     <https://www.gnu.org/licenses/>.  */
> > > >
> > > > -#define MEMCMP wmemcmp
> > > > +#define MEMCMP __wmemcmp
> > > >  #define USE_AS_WMEMCMP 1
> > > > -#include "multiarch/memcmp-sse2.S"
> > > > +#include "memcmp.S"
> > > > +
> > > > +weak_alias (__wmemcmp, wmemcmp)
> > > > --
> > > > 2.25.1
> > > >
> > >
> > >
> > > --
> > > H.J.
>
>
>
> --
> H.J.