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
