PING: [PATCH] i386: Insert ENDBR after __morestack call

[Tsimbalist, Igor V]

> -----Original Message-----
> From: gcc-patches-owner@gcc.gnu.org [mailto:gcc-patches-
> owner@gcc.gnu.org] On Behalf Of H.J. Lu
> Sent: Wednesday, April 18, 2018 3:25 PM
> To: GCC Patches <gcc-patches@gcc.gnu.org>; Tsimbalist, Igor V
> <igor.v.tsimbalist@intel.com>
> Cc: Uros Bizjak <ubizjak@gmail.com>
> Subject: PING: [PATCH] i386: Insert ENDBR after __morestack call
> 
> On Fri, Apr 13, 2018 at 5:56 AM, H.J. Lu <hongjiu.lu@intel.com> wrote:
> > Since __morestack will jump back to its callee via indirect call, we
> > need to insert ENDBR after calling __morestack.
> >
> > OK for trunk?
> >
> > H.J.
> > ----
> > gcc/
> >
> >         PR target/85388
> >         * config/i386/i386.c (ix86_expand_split_stack_prologue): Insert
> >         ENDBR after calling __morestack.
> >
> > gcc/testsuite/
> >
> >         PR target/85388
> >         * gcc.dg/pr85388-1.c: New test.
> >         * gcc.dg/pr85388-2.c: Likewise.
> >         * gcc.dg/pr85388-3.c: Likewise.
> >         * gcc.dg/pr85388-4.c: Likewise.
> >         * gcc.dg/pr85388-5.c: Likewise.
> >         * gcc.dg/pr85388-6.c: Likewise.
> > ---
> >  gcc/config/i386/i386.c           | 11 ++++++-
> >  gcc/testsuite/gcc.dg/pr85388-1.c | 50
> +++++++++++++++++++++++++++++
> >  gcc/testsuite/gcc.dg/pr85388-2.c | 56
> ++++++++++++++++++++++++++++++++
> >  gcc/testsuite/gcc.dg/pr85388-3.c | 65
> +++++++++++++++++++++++++++++++++++++
> >  gcc/testsuite/gcc.dg/pr85388-4.c | 69
> ++++++++++++++++++++++++++++++++++++++++
> >  gcc/testsuite/gcc.dg/pr85388-5.c | 54
> +++++++++++++++++++++++++++++++
> >  gcc/testsuite/gcc.dg/pr85388-6.c | 56
> ++++++++++++++++++++++++++++++++
> >  7 files changed, 360 insertions(+), 1 deletion(-)
> >  create mode 100644 gcc/testsuite/gcc.dg/pr85388-1.c
> >  create mode 100644 gcc/testsuite/gcc.dg/pr85388-2.c
> >  create mode 100644 gcc/testsuite/gcc.dg/pr85388-3.c
> >  create mode 100644 gcc/testsuite/gcc.dg/pr85388-4.c
> >  create mode 100644 gcc/testsuite/gcc.dg/pr85388-5.c
> >  create mode 100644 gcc/testsuite/gcc.dg/pr85388-6.c
> >
> > diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
> > index 03e5c433574..8b4fd8ae30b 100644
> > --- a/gcc/config/i386/i386.c
> > +++ b/gcc/config/i386/i386.c
> > @@ -15242,7 +15242,16 @@ ix86_expand_split_stack_prologue (void)
> >       instruction--we need control flow to continue at the subsequent
> >       label.  Therefore, we use an unspec.  */
> >    gcc_assert (crtl->args.pops_args < 65536);
> > -  emit_insn (gen_split_stack_return (GEN_INT (crtl->args.pops_args)));
> > +  rtx_insn *ret_insn
> > +    = emit_insn (gen_split_stack_return (GEN_INT (crtl->args.pops_args)));
> > +
> > +  if ((flag_cf_protection & CF_BRANCH) && TARGET_IBT)
> > +    {
> > +      /* Insert ENDBR since __morestack will jump back here via indirect
> > +        call.  */
> > +      rtx cet_eb = gen_nop_endbr ();
> > +      emit_insn_after (cet_eb, ret_insn);
> > +    }
> >
> >    /* If we are in 64-bit mode and this function uses a static chain,
> >       we saved %r10 in %rax before calling _morestack.  */
> 
> PING:
> 
> https://gcc.gnu.org/ml/gcc-patches/2018-04/msg00669.html
> 

OK.

Igor

> 
> --
> H.J.