Re: [PATCH] rs6000: Guard bifs {un, }pack_{longdouble, ibm128} under hard float [PR103623]

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

Hi!

On Mon, Apr 11, 2022 at 04:29:40PM +0800, Kewen.Lin wrote:
> on 2022/4/9 1:31 AM, Segher Boessenkool wrote:
> > On Fri, Apr 08, 2022 at 10:09:44AM +0800, Kewen.Lin wrote:
> > For me it fails during combine: the unspec suddenly doesn't recog
> > anymore.  That might be that "d" thing yes, that is problematical.
> > 
> 
> I must miss something, I found in combine pass we still have the
> the insn_code unpacktf_nodm (recog-ed).

That is recognised many passes earlier though.  When combine runs it
will ICE because recog failed (for powerpc64-linux anyway, everything
default, no -mcpu= etc.).

> > Or, try this patch?
> > 
> > ===
> > diff --git a/gcc/config/rs6000/rs6000.md b/gcc/config/rs6000/rs6000.md
> > index fdfbc6566a5c..f05b8358ba0a 100644
> > --- a/gcc/config/rs6000/rs6000.md
> > +++ b/gcc/config/rs6000/rs6000.md
> > @@ -14580,10 +14580,10 @@ (define_insn_and_split "unpack<mode>_dm"
> >    [(set_attr "type" "fp,fpstore,mtvsr,mfvsr,store")])
> >  
> >  (define_insn_and_split "unpack<mode>_nodm"
> > -  [(set (match_operand:<FP128_64> 0 "nonimmediate_operand" "=d,m")
> > +  [(set (match_operand:<FP128_64> 0 "nonimmediate_operand" "=d,m,m")
> >         (unspec:<FP128_64>
> > -        [(match_operand:FMOVE128 1 "register_operand" "d,d")
> > -         (match_operand:QI 2 "const_0_to_1_operand" "i,i")]
> > +        [(match_operand:FMOVE128 1 "register_operand" "d,d,r")
> > +         (match_operand:QI 2 "const_0_to_1_operand" "i,i,i")]
> >          UNSPEC_UNPACK_128BIT))]
> >    "(!TARGET_POWERPC64 || !TARGET_DIRECT_MOVE) && FLOAT128_2REG_P (<MODE>mode)"
> >    "#"
> > @@ -14600,7 +14600,7 @@ (define_insn_and_split "unpack<mode>_nodm"
> >  
> >    operands[3] = gen_rtx_REG (<FP128_64>mode, fp_regno);
> >  }
> > -  [(set_attr "type" "fp,fpstore")])
> > +  [(set_attr "type" "fp,fpstore,store")])
> >  
> >  (define_insn_and_split "pack<mode>"
> >    [(set (match_operand:FMOVE128 0 "register_operand" "=&d")
> > ===
> > 
> > 
> 
> Nice, I confirmed this makes ICE gone, I've filed one new PR
> PR105213 for GCC13 further tracking by associating this patch there.

Cool, I'll commit it later today then (after a final regstrap).  The
_nodm pattern just missed the alternative for no FP regs (the _dm
pattern has it, so just an oversight).



Segher