On Wed, Nov 17, 2021 at 12:09 PM Uros Bizjak <ubizjak@gmail.com> wrote:
>
> On Wed, Nov 17, 2021 at 9:02 PM H.J. Lu <hjl.tools@gmail.com> wrote:
> >
> > On Wed, Nov 17, 2021 at 7:53 AM Uros Bizjak <ubizjak@gmail.com> wrote:
> > >
> > > On Wed, Nov 17, 2021 at 4:35 PM H.J. Lu <hjl.tools@gmail.com> wrote:
> > > >
> > > > Add -mharden-sls= to mitigate against straight line speculation (SLS)
> > > > for function return and indirect branch by adding an INT3 instruction
> > > > after function return and indirect branch.
> > > >
> > > > gcc/
> > > >
> > > >         PR target/102952
> > > >         * config/i386/i386-opts.h (harden_sls): New enum.
> > > >         * config/i386/i386.c (output_indirect_thunk): Mitigate against
> > > >         SLS for function return.
> > > >         (ix86_output_function_return): Likewise.
> > > >         (ix86_output_jmp_thunk_or_indirect): Mitigate against indirect
> > > >         branch.
> > > >         (ix86_output_indirect_jmp): Likewise.
> > > >         (ix86_output_call_insn): Likewise.
> > > >         * config/i386/i386.opt: Add -mharden-sls=.
> > > >         * doc/invoke.texi: Document -mharden-sls=.
> > > >
> > > > gcc/testsuite/
> > > >
> > > >         PR target/102952
> > > >         * gcc.target/i386/harden-sls-1.c: New test.
> > > >         * gcc.target/i386/harden-sls-2.c: Likewise.
> > > >         * gcc.target/i386/harden-sls-3.c: Likewise.
> > > >         * gcc.target/i386/harden-sls-4.c: Likewise.
> > > >         * gcc.target/i386/harden-sls-5.c: Likewise.
>
> OK, with a small nit below.
>
> Thanks,
> Uros.
>
> +mharden-sls=
> +Target RejectNegative Joined Enum(harden_sls) Var(ix86_harden_sls)
> Init(harden_sls_none)
> +Generate code to mitigate against straight line speculation.
> +
> +Enum
> +Name(harden_sls) Type(enum harden_sls)
> +Known choices for mitigation against straight line speculation with
> -mharden-sls=:
> +
> +EnumValue
> +Enum(harden_sls) String(none) Value(harden_sls_none)
> +
> +EnumValue
> +Enum(harden_sls) String(all) Value(harden_sls_all)
>
> Please move the above enum to the last enum.
>
> +
> +EnumValue
> +Enum(harden_sls) String(return) Value(harden_sls_return)
> +
> +EnumValue
> +Enum(harden_sls) String(indirect-branch) Value(harden_sls_indirect_branch)
> +

This is the v4 patch I am checking in.

Thanks.

-- 
H.J.