On Fri, Apr 13, 2018 at 5:56 AM, H.J. Lu <hongjiu...@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
--
H.J.
