[LLVMdev] RFC: Metadata attachments to function definitions

[Duncan P. N. Exon Smith]

> On 2015-Apr-15, at 10:08, Duncan P. N. Exon Smith <dexonsmith at apple.com> wrote:
> 
> 
>> On 2015-Apr-15, at 10:03, Reid Kleckner <rnk at google.com> wrote:
>> 
>> On Wed, Apr 15, 2015 at 9:46 AM, Duncan P. N. Exon Smith <dexonsmith at apple.com> wrote:
>> I'm happy to defer to conventional wisdom here if anyone wants me to
>> (and TBH, I've only been looking at profiles that include debug info,
>> so maybe `sizeof(Function)` matters with -g0).
>> 
>> I think JITs are a more compelling use case for keeping Function small. They shouldn't have to pay too much for a feature they don't use. 
> 
> Ah, of course.  I know nothing of JITs.
> 
> I'll squeeze it into 8B then.  Maybe I'll even start with the same setup
> as `Instruction`, with a side map in the `LLVMContext`.  No reason to
> diverge until/unless there's a real problem with it.

Filed PR23340 to do the IR infrastructure.  Hoping to get this done today.

For now, I'll just use a side map in `LLVMContext`.  We can specialize for
`!dbg` if/when some sort of profile tells us we should.