This is the mail archive of the
mailing list for the GCC project.
Re: PING x2 Re: [PATCH 0/9] separate shrink-wrapping
- From: Segher Boessenkool <segher at kernel dot crashing dot org>
- To: gcc-patches at gcc dot gnu dot org
- Cc: dje dot gcc at gmail dot com
- Date: Thu, 7 Jul 2016 05:16:27 -0500
- Subject: Re: PING x2 Re: [PATCH 0/9] separate shrink-wrapping
- Authentication-results: sourceware.org; auth=none
- References: <firstname.lastname@example.org> <20160627235101.GF27655@gate.crashing.org>
On Mon, Jun 27, 2016 at 06:51:01PM -0500, Segher Boessenkool wrote:
> 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