This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
Re: [PATCH 6/9] sel-sched: Don't mess with register restores
On Mon, Sep 12, 2016 at 11:24:01AM -0600, Jeff Law wrote:
> >sel-sched-ir.c says
> >
> > /* Certain instructions cannot be cloned, and frame related insns and
> > the insn adjacent to NOTE_INSN_EPILOGUE_BEG cannot be moved out of
> > their block. */
> > if (prologue_epilogue_contains (insn))
> >
> >...
> >
> >and I'm just extending that to "epilogue" instructions not in the
> >"epilogue" ;-)
> >
> >If all such epilogue instructions always had a REG_CFA_RESTORE note,
> >we could drop the "old" thing; but even instructions restoring a register
> >do not always have such a note (they can be batched up, and they can be
> >not emitted at all if not shrink-wrapping).
> Can you fix this by registering the separate prologue/epilogue insns in
> prologue_insn_hash and epilogue_insn_hash or does that have unintended
> consequences?
An interesting plan, I'll try.
Segher