[PATCH] Implement function prefix data as an IR feature.

[Duncan Sands]

Hi Reid,

On 29/07/13 19:39, Reid Kleckner wrote:
> On Mon, Jul 29, 2013 at 5:44 AM, Duncan Sands <duncan.sands at gmail.com
> <mailto:duncan.sands at gmail.com>> wrote:
>
>     Hi Peter,
>
>     On 26/07/13 22:57, Peter Collingbourne wrote:
>
>         Ping?
>
>
>     I think requiring the prefix data to start with a bunch of machine specific
>     magic bytes is really horrible.  Why can't codegen insert the magic code
>     sequence automatically?  I don't think this patch should go in as it is.
>
>
> The user will have to know the size of the magic code sequence somehow.

for example, by calling an intrinsic introduced for this purpose, that codegen
lowers to the appropriate number.

Ciao, Duncan.

   Also,
> they might not want it, if they always adjust symbols with bitcast and GEP when
> computing the address of a function.
>
> What if Peter implemented symbol_offset first, and then committed this, with the
> intention that they be used together?
> http://lists.cs.uiuc.edu/pipermail/llvmdev/2013-April/061511.html
>