Displaying 5 results from an estimated 5 matches for "hasphysregouts".
2019 Nov 19
2
Question about physical registers in ISel
...rEmitter::EmitMachineNode assumes that when
the number of outputs of a MachineSDNode is greater than the number of defs
in the corresponding MCInstrDesc, the outputs in the difference will be
placed into physical registers as opposed to virtual registers.
The specific line in question is:
bool HasPhysRegOuts = NumResults > NumDefs &&
II.getImplicitDefs()!=nullptr;
Where NumResults is the number of outputs in the MachineSDNode and NumDefs
comes from the MCInstrDesc and ultimately the TableGen definition of the
instruction. I do not know why this assumption is made or what code depends
on it,...
2019 Nov 19
2
Question about physical registers in ISel
...umes that when
> the number of outputs of a MachineSDNode is greater than the number of defs
> in the corresponding MCInstrDesc, the outputs in the difference will be
> placed into physical registers as opposed to virtual registers.
>
> The specific line in question is:
> bool HasPhysRegOuts = NumResults > NumDefs &&
> II.getImplicitDefs()!=nullptr;
>
> Where NumResults is the number of outputs in the MachineSDNode and NumDefs
> comes from the MCInstrDesc and ultimately the TableGen definition of the
> instruction. I do not know why this assumption is made or...
2019 Nov 19
2
Question about physical registers in ISel
...the number of outputs of a MachineSDNode is greater than the number of defs
>> in the corresponding MCInstrDesc, the outputs in the difference will be
>> placed into physical registers as opposed to virtual registers.
>>
>> The specific line in question is:
>> bool HasPhysRegOuts = NumResults > NumDefs &&
>> II.getImplicitDefs()!=nullptr;
>>
>> Where NumResults is the number of outputs in the MachineSDNode and
>> NumDefs comes from the MCInstrDesc and ultimately the TableGen definition
>> of the instruction. I do not know why this as...
2017 Feb 14
2
Adding FP environment register modeling for constrained FP nodes
...g the FP opcodes should be our goal. I just wasn’t sure that was entirely possible. I’ll try adding implicit defs in the way you’ve suggested, but I’m concerned that there may be code that relies on the TII for that kind of thing -- for instance, InstrEmitter::EmitMachineNode() does this:
bool HasPhysRegOuts = NumResults > NumDefs && II.getImplicitDefs()!=nullptr;
where “NumDefs” comes from TII and “NumResults” comes from the node. Obviously we can fix that up as needed, but it seems like a weak point in the design. Perhaps it is still better than trying to maintain a duplicate set of opc...
2019 Nov 20
2
Question about physical registers in ISel
...s of a MachineSDNode is greater than the number of defs
>>> in the corresponding MCInstrDesc, the outputs in the difference will be
>>> placed into physical registers as opposed to virtual registers.
>>>
>>> The specific line in question is:
>>> bool HasPhysRegOuts = NumResults > NumDefs &&
>>> II.getImplicitDefs()!=nullptr;
>>>
>>> Where NumResults is the number of outputs in the MachineSDNode and
>>> NumDefs comes from the MCInstrDesc and ultimately the TableGen definition
>>> of the instruction. I do...