[LLVMdev] metadata syntax

[Chris Lattner]

On Apr 23, 2009, at 10:18 AM, Dale Johannesen wrote:

>
> On Apr 23, 2009, at 10:14 AMPDT, Devang Patel wrote:
>
>> On Wed, Apr 22, 2009 at 7:30 PM, Nick Lewycky <nicholas at mxc.ca>  
>> wrote:
>>>
>>> The first client for metadata I have in mind for metadata is TBAA.
>>
>> Why do you think that TBAA will beat Debug Info on this front ;)
>>
>> Back to original topic, I still don't see real good reason to refer
>> instructions in other function. I'd rather wait till we have a good
>> reason to use it. And if we have to invent a new syntax then pl.  
>> avoid
>> overloading "/".
>
> gcc has an extension to allow the address of labels to be taken and
> exported.  IMO it would not be a great loss if llvm refused to support
> this, but I suppose somebody somewhere is using it...

Metadata can't be used for this, because metadata is a "best effort"  
thing, not a guaranteed way to track data.

-Chris