On Mon, Aug 12, 2024 at 10:59:01AM -0500, Peter Bergner wrote:
> Ping * 3. [Message-ID: <1e003d78-3b2e-4263-830a-7c00a3e9d...@linux.ibm.com>]
>
> Segher, this resolves the issues you mentioned in your review.
> This was on the top of your patch review queue before, so maybe
> we have queue overflow? ;-)
Or wrap-around? Who knows :-)
The patch is okay for trunk. Thanks!
Segher
> On 6/18/24 5:59 PM, Peter Bergner wrote:
> > Updated patch. This passed bootstrap and regtesting on powerpc64le-linux
> > with no regressions. Ok for trunk?
> >
> > Changes from v1:
> > 1. Moved the disabling of shrink-wrapping to rs6000_emit_prologue
> > and beefed up comment. Used a more accurate test.
> > 2. Added comment to the test case on why rop_ok is needed.
> >
> > Peter
> >
> >
> > rs6000: ROP - Do not disable shrink-wrapping for leaf functions [PR114759]
> >
> > Only disable shrink-wrapping when using -mrop-protect when we know we
> > will be emitting the ROP-protect hash instructions (ie, non-leaf functions).
> >
> > 2024-06-17 Peter Bergner <berg...@linux.ibm.com>
> >
> > gcc/
> > PR target/114759
> > * config/rs6000/rs6000.cc (rs6000_override_options_after_change): Move
> > the disabling of shrink-wrapping from here....
> > * config/rs6000/rs6000-logue.cc (rs6000_emit_prologue): ...to here.
> >
> > gcc/testsuite/
> > PR target/114759
> > * gcc.target/powerpc/pr114759-1.c: New test.
> > ---
> > gcc/config/rs6000/rs6000-logue.cc | 5 +++++
> > gcc/config/rs6000/rs6000.cc | 4 ----
> > gcc/testsuite/gcc.target/powerpc/pr114759-1.c | 16 ++++++++++++++++
> > 3 files changed, 21 insertions(+), 4 deletions(-)
> > create mode 100644 gcc/testsuite/gcc.target/powerpc/pr114759-1.c
> >
> > diff --git a/gcc/config/rs6000/rs6000-logue.cc
> > b/gcc/config/rs6000/rs6000-logue.cc
> > index 193e2122c0f..c384e48e378 100644
> > --- a/gcc/config/rs6000/rs6000-logue.cc
> > +++ b/gcc/config/rs6000/rs6000-logue.cc
> > @@ -3018,6 +3018,11 @@ rs6000_emit_prologue (void)
> > && (lookup_attribute ("no_split_stack",
> > DECL_ATTRIBUTES
> > (cfun->decl))
> > == NULL));
> > + /* If we are inserting ROP-protect hash instructions, disable shrink-wrap
> > + until the bug where the hashst insn is emitted in the wrong location
> > + is fixed. See PR101324 for details. */
> > + if (info->rop_hash_size)
> > + flag_shrink_wrap = 0;
> >
> > frame_pointer_needed_indeed
> > = frame_pointer_needed && df_regs_ever_live_p
> > (HARD_FRAME_POINTER_REGNUM);
> > diff --git a/gcc/config/rs6000/rs6000.cc b/gcc/config/rs6000/rs6000.cc
> > index e4dc629ddcc..fd6e013c346 100644
> > --- a/gcc/config/rs6000/rs6000.cc
> > +++ b/gcc/config/rs6000/rs6000.cc
> > @@ -3427,10 +3427,6 @@ rs6000_override_options_after_change (void)
> > }
> > else if (!OPTION_SET_P (flag_cunroll_grow_size))
> > flag_cunroll_grow_size = flag_peel_loops || optimize >= 3;
> > -
> > - /* If we are inserting ROP-protect instructions, disable shrink wrap. */
> > - if (rs6000_rop_protect)
> > - flag_shrink_wrap = 0;
> > }
> >
> > #ifdef TARGET_USES_LINUX64_OPT
> > diff --git a/gcc/testsuite/gcc.target/powerpc/pr114759-1.c
> > b/gcc/testsuite/gcc.target/powerpc/pr114759-1.c
> > new file mode 100644
> > index 00000000000..579e08e920f
> > --- /dev/null
> > +++ b/gcc/testsuite/gcc.target/powerpc/pr114759-1.c
> > @@ -0,0 +1,16 @@
> > +/* { dg-do compile } */
> > +/* { dg-options "-O2 -mdejagnu-cpu=power10 -mrop-protect
> > -fdump-rtl-pro_and_epilogue" } */
> > +/* { dg-require-effective-target rop_ok } Only enable on supported ABIs. */
> > +
> > +/* Verify we still attempt shrink-wrapping when using -mrop-protect
> > + and there are no function calls. */
> > +
> > +long
> > +foo (long arg)
> > +{
> > + if (arg)
> > + asm ("" ::: "r20");
> > + return 0;
> > +}
> > +
> > +/* { dg-final { scan-rtl-dump-times "Performing shrink-wrapping" 1
> > "pro_and_epilogue" } } */
