On Thu, 6 Oct 2022 at 12:06, Richard Sandiford <richard.sandif...@arm.com>
wrote:
> Philipp Tomsich <philipp.toms...@vrull.eu> writes:
> > Fixes: 341573406b39
> >
> > Don't subtract one from the result of strnlen() when trying to point
> > to the first character after the current string. This issue would
> > cause individual characters (where the 128 byte buffers are stitched
> > together) to be lost.
> >
> > gcc/ChangeLog:
> >
> > * config/aarch64/driver-aarch64.cc (readline): Fix off-by-one.
> >
> > gcc/testsuite/ChangeLog:
> >
> > * gcc.target/aarch64/cpunative/info_18: New test.
> > * gcc.target/aarch64/cpunative/native_cpu_18.c: New test.
> >
> > Signed-off-by: Philipp Tomsich <philipp.toms...@vrull.eu>
> >
> > ---
> >
> > Changes in v2:
> > - Add a a regression test (as per review comment).
> >
> > gcc/config/aarch64/driver-aarch64.cc | 4 ++--
> > .../gcc.target/aarch64/cpunative/info_18 | 8 ++++++++
> > .../gcc.target/aarch64/cpunative/native_cpu_18.c | 15 +++++++++++++++
> > 3 files changed, 25 insertions(+), 2 deletions(-)
> > create mode 100644 gcc/testsuite/gcc.target/aarch64/cpunative/info_18
> > create mode 100644
> gcc/testsuite/gcc.target/aarch64/cpunative/native_cpu_18.c
> >
> > diff --git a/gcc/config/aarch64/driver-aarch64.cc
> b/gcc/config/aarch64/driver-aarch64.cc
> > index 52ff537908e..48250e68034 100644
> > --- a/gcc/config/aarch64/driver-aarch64.cc
> > +++ b/gcc/config/aarch64/driver-aarch64.cc
> > @@ -203,9 +203,9 @@ readline (FILE *f)
> > return std::string ();
> > /* If we're not at the end of the line then override the
> > \0 added by fgets. */
> > - last = strnlen (buf, size) - 1;
> > + last = strnlen (buf, size);
> > }
> > - while (!feof (f) && buf[last] != '\n');
> > + while (!feof (f) && (last > 0 && buf[last - 1] != '\n'));
>
> Very minor, but: I think the normal GCC style would be to avoid the
> extra (...).
>
> OK with that change, thanks. OK for backports too after a settling period.
>
Applied to master (with that change). Thanks!
I'll backport around the end of this month, if no new issues are caused by
this change.
Philipp.
>
> Richard
>
> >
> > std::string result (buf);
> > free (buf);
> > diff --git a/gcc/testsuite/gcc.target/aarch64/cpunative/info_18
> b/gcc/testsuite/gcc.target/aarch64/cpunative/info_18
> > new file mode 100644
> > index 00000000000..25061a4abe8
> > --- /dev/null
> > +++ b/gcc/testsuite/gcc.target/aarch64/cpunative/info_18
> > @@ -0,0 +1,8 @@
> > +processor : 0
> > +BogoMIPS : 2000.00
> > +Features : fp asimd evtstrm aes pmull sha1 sha2 crc32 atomics fphp
> asimdhp cpuid asimdrdm jscvt fcma lrcpc dcpop sha3 asimddp sha512 asimdfhm
> dit uscat ilrcpc flagm ssbs sb dcpodp flagm2 frint i8mm bf16 rng ecv
> > +CPU implementer : 0xc0
> > +CPU architecture: 8
> > +CPU variant : 0x0
> > +CPU part : 0xac3
> > +CPU revision : 0
> > diff --git a/gcc/testsuite/gcc.target/aarch64/cpunative/native_cpu_18.c
> b/gcc/testsuite/gcc.target/aarch64/cpunative/native_cpu_18.c
> > new file mode 100644
> > index 00000000000..b5f0a3005f5
> > --- /dev/null
> > +++ b/gcc/testsuite/gcc.target/aarch64/cpunative/native_cpu_18.c
> > @@ -0,0 +1,15 @@
> > +/* { dg-do compile { target { { aarch64*-*-linux*} && native } } } */
> > +/* { dg-set-compiler-env-var GCC_CPUINFO
> "$srcdir/gcc.target/aarch64/cpunative/info_18" } */
> > +/* { dg-additional-options "-mcpu=native" } */
> > +
> > +int main()
> > +{
> > + return 0;
> > +}
> > +
> > +/* { dg-final { scan-assembler {\.arch
> armv8.6-a\+crc\+fp16\+aes\+sha3\+rng} } } */
> > +
> > +/* Test one where the boundary of buffer size would overwrite the last
> > + character read when stitching the fgets-calls together. With the
> > + test data provided, this would truncate the 'sha512' into 'ha512'
> > + (dropping the 'sha3' feature). */
>
