[llvm-commits] [PATCH] Add Pattern ID Information

[Jakob Stoklund Olesen]

On Aug 4, 2011, at 5:33 PM, David A. Greene wrote:

> Jakob Stoklund Olesen <stoklund at 2pi.dk> writes:
>> Cleaning up isel debug output would be great. It is way too noisy.
> 
> It's an admirable goal but way beyond the scope of this patch.
> 
>>> It's really very difficult to map a piece of an asm file back to the
>>> isel debug output related to it.
>> 
>> That also applies to DAG combine, scheduling, and even InstCombine.
> 
> Yes it does.  In other compiler projects I have emitted similar asm
> comments to track various transformations.  But that's not on the table
> here.

I could perhaps see the utility of a general mechanism for annotating machine instructions, but as you say, this patch doesn't bring us any closer to that. It is one more ad-hoc thing on top of the existing AsmPrinterFlags.

We added AsmPrinterFlags almost two years ago. In that time, nobody has defined more flags, and the existing ReloadReuse flag is only written by VirtRegRewriter.cpp which isn't even in the default pipeline any more.

I simply don't think this is useful to anyone else.

/jakob