Re: PING x2 Re: [PATCH 0/9] separate shrink-wrapping

[Segher Boessenkool <segher@kernel.crashing.org>]

Ping.

On Mon, Jun 27, 2016 at 06:51:01PM -0500, Segher Boessenkool wrote:
> Ping.
> 
> On Wed, Jun 08, 2016 at 01:47:31AM +0000, Segher Boessenkool wrote:
> > This patch series introduces separate shrink-wrapping.
> > 
> > There are many things the prologue/epilogue of a function do, and most of
> > those things can be done independently.  For example, most of the time,
> > for many targets, the save of callee-saved registers can be done later
> > than the "main" prologue.
> > 
> > Doing so helps quite a bit because the prologue is expensive for functions
> > that do not need everything it does done for every path through the
> > function; often, the hot paths do not need much at all, e.g. not those
> > things the prologue needs to do for the function to call other functions.
> > 
> > The first patch creates a command-line flag, some hooks, a status flag
> > ("is this function wrapped separately", used by later passes), and
> > documentation for these things.
> > 
> > The next six patches are to prevent later passes from mishandling the
> > epilogue instructions that now appear before the epilogue: mostly, you
> > cannot do much to instructions with a REG_CFA_RESTORE note without
> > confusing dwarf2cfi.  The cprop one is for prologue instructions.
> > 
> > Then, the main patch.  And finally a patch for PowerPC that implements
> > separate wrapping for GPRs and LR.
> > 
> > Tested on powerpc64-linux (-m32/-m64, -mlra/-mno-lra), and on
> > powerpc64le-linux.  Previous versions of this series also tested on
> > x86_64-linux.
> > 
> > Is this okay for trunk?
> > 
> > 
> > Segher
> > 
> > 
> > Segher Boessenkool (9):
> >   separate shrink-wrap: New command-line flag, status flag, hooks, and doc
> >   cfgcleanup: Don't confuse CFI when -fshrink-wrap-separate
> >   dce: Don't dead-code delete separately wrapped restores
> >   regrename: Don't rename restores
> >   regrename: Don't run if function was separately shrink-wrapped
> >   sel-sched: Don't mess with register restores
> >   cprop: Leave RTX_FRAME_RELATED_P instructions alone
> >   shrink-wrap: shrink-wrapping for separate concerns
> >   rs6000: Separate shrink-wrapping
> > 
> >  gcc/cfgcleanup.c           |   5 +
> >  gcc/common.opt             |   4 +
> >  gcc/config/rs6000/rs6000.c | 257 ++++++++++++++++--
> >  gcc/dce.c                  |   9 +
> >  gcc/doc/invoke.texi        |  11 +-
> >  gcc/doc/tm.texi            |  53 ++++
> >  gcc/doc/tm.texi.in         |  29 ++
> >  gcc/emit-rtl.h             |   4 +
> >  gcc/function.c             |  15 +-
> >  gcc/regcprop.c             |   3 +
> >  gcc/regrename.c            |  12 +-
> >  gcc/sel-sched-ir.c         |   1 +
> >  gcc/shrink-wrap.c          | 647 +++++++++++++++++++++++++++++++++++++++++++++
> >  gcc/shrink-wrap.h          |   1 +
> >  gcc/target.def             |  56 ++++
> >  15 files changed, 1088 insertions(+), 19 deletions(-)
> > 
> > -- 
> > 1.9.3