Re: [PATCH 2/4] x86: Add -mfunction-return=

2018-01-13 Thread H.J. Lu
On Sat, Jan 13, 2018 at 9:31 AM, Jan Hubicka wrote: >> On Sat, Jan 13, 2018 at 8:51 AM, Woodhouse, David wrote: >> > On Sat, 2018-01-13 at 08:09 -0800, H.J. Lu wrote: >> >> >> >> > Again please extend both documentation hunks so it is clear what is >> >> >

Re: [PATCH 2/4] x86: Add -mfunction-return=

2018-01-13 Thread Jan Hubicka
> On Sat, Jan 13, 2018 at 8:51 AM, Woodhouse, David wrote: > > On Sat, 2018-01-13 at 08:09 -0800, H.J. Lu wrote: > >> > >> > Again please extend both documentation hunks so it is clear what is > >> > purpose > >> > of this hack. > >> > >> David, can you help here? > > > > On

Re: [PATCH 2/4] x86: Add -mfunction-return=

2018-01-13 Thread H.J. Lu
On Sat, Jan 13, 2018 at 8:51 AM, Woodhouse, David wrote: > On Sat, 2018-01-13 at 08:09 -0800, H.J. Lu wrote: >> >> > Again please extend both documentation hunks so it is clear what is purpose >> > of this hack. >> >> David, can you help here? > > On most older CPUs the

Re: [PATCH 2/4] x86: Add -mfunction-return=

2018-01-13 Thread Woodhouse, David
On Sat, 2018-01-13 at 08:09 -0800, H.J. Lu wrote: > > > Again please extend both documentation hunks so it is clear what is purpose > > of this hack. > > David, can you help here? On most older CPUs the indirect branch issue is limited to actual indirect branches. On Skylake-era CPUs, however,

Re: [PATCH 2/4] x86: Add -mfunction-return=

2018-01-13 Thread H.J. Lu
On Fri, Jan 12, 2018 at 9:55 AM, Jan Hubicka wrote: >> Add -mfunction-return= option to convert function return to call and >> return thunks. The default is 'keep', which keeps function return >> unmodified. 'thunk' converts function return to call and return thunk. >>

Re: [PATCH 2/4] x86: Add -mfunction-return=

2018-01-12 Thread Jan Hubicka
> Add -mfunction-return= option to convert function return to call and > return thunks. The default is 'keep', which keeps function return > unmodified. 'thunk' converts function return to call and return thunk. > 'thunk-inline' converts function return to inlined call and return thunk. >

[PATCH 2/4] x86: Add -mfunction-return=

2018-01-12 Thread H.J. Lu
Add -mfunction-return= option to convert function return to call and return thunks. The default is 'keep', which keeps function return unmodified. 'thunk' converts function return to call and return thunk. 'thunk-inline' converts function return to inlined call and return thunk. 'thunk-extern'