Displaying 10 results from an estimated 10 matches for "allowfusionglob".
2018 Aug 20
3
Condition code in DAGCombiner::visitFADDForFMACombine?
...ate rounding.
bool HasFMAD = (LegalOperations && TLI.isOperationLegal(ISD::FMAD, VT));
static bool isContractable(SDNode *N) {
SDNodeFlags F = N->getFlags();
return F.hasAllowContract() || F.hasAllowReassociation();
}
bool CanFuse = Options.UnsafeFPMath || isContractable(N);
bool AllowFusionGlobally = (Options.AllowFPOpFusion == FPOpFusion::Fast ||
CanFuse || HasFMAD);
// If the addition is not contractable, do not combine.
if (!AllowFusionGlobally && !isContractable(N))
return SDValue();
Specifically the AllowFusionGlobally, I would have expected something more
like:
bool Al...
2018 Aug 22
2
Condition code in DAGCombiner::visitFADDForFMACombine?
...perationLegal(ISD::FMAD, VT));
>
> static bool isContractable(SDNode *N) {
> SDNodeFlags F = N->getFlags();
> return F.hasAllowContract() || F.hasAllowReassociation();
> }
>
> bool CanFuse = Options.UnsafeFPMath || isContractable(N);
> bool AllowFusionGlobally = (Options.AllowFPOpFusion ==
> FPOpFusion::Fast || CanFuse || HasFMAD);
> // If the addition is not contractable, do not combine.
> if (!AllowFusionGlobally && !isContractable(N))
> return SDValue();
>
> Specifically the AllowFusionGlobally,...
2018 Aug 22
4
Condition code in DAGCombiner::visitFADDForFMACombine?
...sContractable(SDNode *N) {
> > SDNodeFlags F = N->getFlags();
> > return F.hasAllowContract() || F.hasAllowReassociation();
> > }
> >
> > bool CanFuse = Options.UnsafeFPMath || isContractable(N);
> > bool AllowFusionGlobally = (Options.AllowFPOpFusion ==
> > FPOpFusion::Fast || CanFuse || HasFMAD);
> > // If the addition is not contractable, do not combine.
> > if (!AllowFusionGlobally && !isContractable(N))
> > return SDValue();
> >...
2018 Aug 22
2
Condition code in DAGCombiner::visitFADDForFMACombine?
...s F = N->getFlags();
> > > return F.hasAllowContract() ||
> F.hasAllowReassociation();
> > > }
> > >
> > > bool CanFuse = Options.UnsafeFPMath || isContractable(N);
> > > bool AllowFusionGlobally = (Options.AllowFPOpFusion ==
> > > FPOpFusion::Fast || CanFuse || HasFMAD);
> > > // If the addition is not contractable, do not combine.
> > > if (!AllowFusionGlobally && !isContractable(N))
> > > ...
2018 Aug 23
2
Condition code in DAGCombiner::visitFADDForFMACombine?
...; SDNodeFlags F = N->getFlags();
>>> > return F.hasAllowContract() || F.hasAllowReassociation();
>>> > }
>>> >
>>> > bool CanFuse = Options.UnsafeFPMath || isContractable(N);
>>> > bool AllowFusionGlobally = (Options.AllowFPOpFusion ==
>>> > FPOpFusion::Fast || CanFuse || HasFMAD);
>>> > // If the addition is not contractable, do not combine.
>>> > if (!AllowFusionGlobally && !isContractable(N))
>>> >...
2018 Aug 23
2
Condition code in DAGCombiner::visitFADDForFMACombine?
...F = N->getFlags();
>>>> > return F.hasAllowContract() || F.hasAllowReassociation();
>>>> > }
>>>> >
>>>> > bool CanFuse = Options.UnsafeFPMath || isContractable(N);
>>>> > bool AllowFusionGlobally = (Options.AllowFPOpFusion ==
>>>> > FPOpFusion::Fast || CanFuse || HasFMAD);
>>>> > // If the addition is not contractable, do not combine.
>>>> > if (!AllowFusionGlobally && !isContractable(N))
>>>>...
2018 Aug 23
3
Condition code in DAGCombiner::visitFADDForFMACombine?
...);
>>>>> > return F.hasAllowContract() || F.hasAllowReassociation();
>>>>> > }
>>>>> >
>>>>> > bool CanFuse = Options.UnsafeFPMath || isContractable(N);
>>>>> > bool AllowFusionGlobally = (Options.AllowFPOpFusion ==
>>>>> > FPOpFusion::Fast || CanFuse || HasFMAD);
>>>>> > // If the addition is not contractable, do not combine.
>>>>> > if (!AllowFusionGlobally && !isContractable(N))
>>...
2018 Aug 23
2
Condition code in DAGCombiner::visitFADDForFMACombine?
...);
>>>> > }
>>>> >
>>>> > bool CanFuse = Options.UnsafeFPMath ||
>>>> isContractable(N);
>>>> > bool AllowFusionGlobally =
>>>> (Options.AllowFPOpFusion ==
>>>> > FPOpFusion::Fast || CanFuse || HasFMAD);
>>>> > // If the addition is not
>>>> contractable, do not combi...
2019 Jul 10
2
RFC: change -fp-contract=off to actually disable FMAs
...ast double %mul, %c
ret double %add
}
$ llc -mattr=+fma fma.ll -fp-contract=off -o - | grep vfmadd
vfmadd213sd %xmm2, %xmm1, %xmm0 # xmm0 = (xmm1 * xmm0) + xmm2
It still generates an fma due to the logic in DAGCombiner:
bool CanFuse = Options.UnsafeFPMath || isContractable(N);
bool AllowFusionGlobally = (Options.AllowFPOpFusion == FPOpFusion::Fast ||
CanFuse || HasFMAD);
In this case, UnsafeFPMath is false but isContractable() is true since the
FADD node is tagged as 'fast'. A simple fix would just be to check for
-fp-contract=off, however, I also fou...
2018 Aug 21
3
Condition code in DAGCombiner::visitFADDForFMACombine?
> On Aug 21, 2018, at 17:57, Ryan Taylor <ryta1203 at gmail.com> wrote:
>
> Matt,
> I'm sorry, actually it's fma not fmad.
>
> In the post-legalizer DAG combine for the given code it's producing fma not fmad. That doens't seem correct.
>
The contract is on the fadd. I’m not really sure what the rule is supposed to be for contract between the nodes.