[patch] Shark reroute LLVM atomic intrinsics to Zero

[Andrew Haley]

Robert Schuster wrote:

> Andrew Haley schrieb:
>> Definitely; we really don't want a function call just do do an atomic
>> cmpxchg.
> That is why I opted for enabling it only for the arches that really need
> it by using #ifdef.

Yes.  That is the correct answer.

>>  This is really just a workaround for an llvm bug, and hopefully
>> it'll soon go away.
> Do you know more than me?
> 
> The 'bug' is actually a missing feature and I don't see someone working
> on this. I tried fixing it myself but it will take me a while until
> understand how to use llvm's tablegen syntax to describe the generation
> of a series of instructions for the compiler.

Maybe our idea of "soon" varies.  It'll have to be fixed before LLVM's ARM
back-end is used for real work.  But these really are early days for LLVM
JIT on ARM.

Andrew.