[LLVMdev] tblgen internals

[Garrison Venn]

Hi Chris,

Thanks for the review!

I believe I caught most of the syntax style issues with the attached patch. It only contains
these style changes.

On Dec 12, 2010, at 19:30, Chris Lattner wrote:

> 
> On Dec 12, 2010, at 10:54 AM, Garrison Venn wrote:
> 
>> 
>> Hey Chris,
>> 
>> The following patch removes all global references to a RecordKeeper instance for the tblgen
>> utility. 
> 
> This looks like great progress to me, applied in r121659.
> 
> That said, it is suboptimal for Record to have to have a RecordKeeper& in it.  I haven't looked at the code in a long time, is it feasible to detangle that out of record, or is it not worth it?

I'll see if I can come up with another approach. This internal reference was motivated by the
Record::setName(...) and UnOpInit::Fold(...) implementations accessing the previous 
global RecordKeeper instance. We could add a RecordKeeper& argument to setName
and OpInit::Fold(...). However as I'm looking at the code, while adding this argument to Fold
for TGParser use is not an issue as it has a RecordKeeper instance, the other Record
classes have a problem because they lack this type of instance. See for example the
implementation of Record.cpp:OpInit::resolveBitReference(...). These methods (such as
resolveBitReference(...) and resolveReferences(...) need a context containing a RecordKeeper
for their evaluation. A cursory glance for the uses of Record::setName(...) seems to imply that adding a 
RecordKeeper& argument would not be an issue. I'll keep on looking for other mechanisms.

> 
> Another random question: why is createRecord better than using "new Record"?  If createRecord is better, it would be good to make the Record ctor private so the code doesn't evolve into sometimes using one and sometimes using the other.

This was another syntactic hack. I personally prefer the factory approach, but I cannot
as it stands get rid of the explicit Record constructor because of MultiClass. It has member
variable of type Record and constructs this member directly using the Record constructor.
It therefore does not need the allocation provided by createRecord. I could push the Record
constructor to protected or private and make MultiClass a friend. This is ugly so I think I should 
drop the factory method in favor of new Record. Like I said the factory method is mainly sugar 
anyway.

I'm assuming your ok with dropping the RecordKeeper::createRecord(...). I'll send that
patch tomorrow.

Thanks again for taking time to review.

Garrison 

> 

> Some minor coding style things:
> 
> ...

> -Chris
> 

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