llvm dev - Aug 2017 - How do set 'nest' addribute in an indirect call?

On 08/24/2017 09:40 AM, Tim Northover wrote:
> On 17 August 2017 at 15:15, Rodney M. Bates via llvm-dev
> <llvm-dev at lists.llvm.org> wrote:
>> For an indirect call, i.e., on a function whose address is runtime
variable,
>> I can't find any place/way to attach this attribute. 
LLVMAddAttribute
>> won't take a type.
>
> In the C++ API you'd add the attribute to the CallInst. I've not
used
> any of the wrappers, but I think you might get what you want via
> LLVMAddCallSiteAttribute.
I don't find LLVMAddCallSiteAttribute or anything similar in include/llvm.
(I am using 3.6.1)

I do see llvm::CallInst::addAttribute

  /// addAttribute - adds the attribute to the list of attributes.
   void addAttribute(unsigned i, Attribute::AttrKind attr);

Is 'i' the number of the parameter that gets the attribute?  This
matters for 'nest'.
Is it zero-origin numbering, left-to-right?

I have an out-of-tree binding already for a small set of things not in Core.h,
and it's not hard to add things in ones & twos.

>
> Cheers.
>
> Tim.
>
-- 
Rodney Bates
rodney.m.bates at acm.org

On 24 August 2017 at 13:43, Rodney M. Bates <rodney_bates at lcwb.coop>
wrote:
> I don't find LLVMAddCallSiteAttribute or anything similar in
include/llvm.
> (I am using 3.6.1)
It may have been added since then, it definitely exists in trunk.
>  /// addAttribute - adds the attribute to the list of attributes.
>   void addAttribute(unsigned i, Attribute::AttrKind attr);
>
> Is 'i' the number of the parameter that gets the attribute?  This
matters
> for 'nest'. Is it zero-origin numbering, left-to-right?
I believe 0 is the return and args start at 1 (see
include/llvm/IR/Attributes.h, especially the AttrIndex enum).
> I have an out-of-tree binding already for a small set of things not in
> Core.h, and it's not hard to add things in ones & twos.
Oh good, that'll make using a slightly older version less of a
disaster and more an inconvenience.

Cheers.

Tim.

On 08/24/2017 03:48 PM, Tim Northover wrote:
> On 24 August 2017 at 13:43, Rodney M. Bates <rodney_bates at
lcwb.coop> wrote:
>> I don't find LLVMAddCallSiteAttribute or anything similar in
include/llvm.
>> (I am using 3.6.1)
>
> It may have been added since then, it definitely exists in trunk.
>
Looking to see how to write a binding for CallInst::addAttr, I came across
LLVMAddInstrAttribute.  Tried it out and it did want I want.  It's
a little surprising, because it unwraps its operand to an Instruction,
a superclass of CallInstr.  But I'm happy to let that go uninvestigated.

Thanks for the help.  Putting it on starting from the CallInstr instead of
directly on a parameter was the breakout info for me.
>>  /// addAttribute - adds the attribute to the list of attributes.
>>   void addAttribute(unsigned i, Attribute::AttrKind attr);
>>
>> Is 'i' the number of the parameter that gets the attribute? 
This matters
>> for 'nest'. Is it zero-origin numbering, left-to-right?
>
> I believe 0 is the return and args start at 1 (see
> include/llvm/IR/Attributes.h, especially the AttrIndex enum).
>
>> I have an out-of-tree binding already for a small set of things not in
>> Core.h, and it's not hard to add things in ones & twos.
>
> Oh good, that'll make using a slightly older version less of a
> disaster and more an inconvenience.
>
> Cheers.
>
> Tim.
>
-- 
Rodney Bates
rodney.m.bates at acm.org