[LLVMdev] [PATCH] SelectionDAG Debugging

[Dan Gohman]

On Jan 15, 2010, at 2:34 PM, David Greene wrote:

> On Friday 15 January 2010 16:23, Dan Gohman wrote:
>> On Jan 15, 2010, at 1:38 PM, David Greene wrote:
>>> On Friday 15 January 2010 15:09, Dan Gohman wrote:
>>>>> Sound good? reimplement
>>>> 
>>>> Unlimited-recursion dumping is what the existing dump routines
>>>> already do, so it's a little odd to have a flag to allow these
>>> 
>>> Which existing dump routines are you referring to?
>> 
>> dumpr(). I guess it wasn't commented. It is now :-).
> 
> Ah, one thing.  dumpr uses DumpNodesr which does the "once" thing.
> I actually would prefer a full dump.  Perhaps we shouldn't try to
> unify them, or maybe provide a flag to control behavior.  In the
> past separate APIs have been preferred over flags.  I can rename
> the ones I added to be more consistent with the existing stuff.
> 
> Opinions?

I use the GraphViz viewer almost exclusively, so I don't have a
strong opinion.

Methods with lots of flags are inconvenient to call from a debugger.
I'd suggesting coming up with a few common use cases, and providing
interfaces to cover those use cases, and not trying to provide
lots of extra generality.

If SDNode::dumpr() had built-in cycle detection, and indicated
cycles with big capital letters, would you still want a recursive
dump which doesn't do the "once" thing?  Or, if the "once" thing
had a more human-oriented syntax, would it be usable?

Dan