[LLVMdev] addrspace attribute and intrisics

[Benedict Gaster]

Thanks, I can now see that this can be implemented with Verifier.cpp.

Even with this ability It is unclear that defining llvm.memory.barrier  
with an explicit address space argument is preferred over the  
llvm.memory.fence definition where the addrspace is encoded as part of  
the type as will be the case with the other atomic operations. What do  
you think?

Ben

On 7 Jul 2008, at 13:43, Gordon Henriksen wrote:

> On 2008-07-07, at 05:40, Benedict Gaster wrote:
>
>>        %r1 = call i32 @llvm.atomic.load.add.p0i32( i32 addrspace(0)*
>> %ptr0, i32 4)
>> 	%r2 = call i32 @llvm.atomic.load.add.p11i32( i32 addrspace(11)*
>> %ptr11, i32 4)
>> 	call void @llvm.memory.barrier(i1 true, i1 true, i1 false, i1 false,
>> i32 11, i1 false) ; force read-modify-write %ptr11 to complete
>>
>> A problem with this approach is that developing a new pass over the
>> IL that works with address spaces, will have to include knowledge
>> that for certain operations address space information is encoded as
>> data rather than as types and in general, it may not be able to
>> statically determine the particular address space.
>
> It's quite possible to restrict an argument to an intrinsic to an
> immediate constant. See llvm.gcroot for an example.
>
> — Gordon
>
>
> _______________________________________________
> LLVM Developers mailing list
> LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
>