https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102952
--- Comment #27 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by H.J. Lu <h...@gcc.gnu.org>: https://gcc.gnu.org/g:53a643f8568067d7700a9f2facc8ba39974973d3 commit r12-5353-g53a643f8568067d7700a9f2facc8ba39974973d3 Author: H.J. Lu <hjl.to...@gmail.com> Date: Wed Oct 27 07:48:54 2021 -0700 x86: Add -mharden-sls=[none|all|return|indirect-branch] 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.