[cfe-dev] always_inline and noinline attributes

[Devang Patel]

On Jul 23, 2008, at 3:10 PM, Matthijs Kooijman wrote:

> With plain gcc I assume?

Yes.

> I was thinking of doing this stripping in the tool generating the  
> LLVM module,
> so opt (or perhaps clang?). It should always be able to just throw  
> away the
> always_inline global and the function should then be just a normal  
> function.
>
> I'm not sure if having such a strip-always_inline option is needed,  
> at least
> not if the default is to preserve always_inline information.

What I'm worried is - if always_inline info is not stripped away the  
LTO inliner will obey always_inline. In this case, it is not  
appropriate to say "LTO may not inline functions, marked as  
always_inline",  across translation unit".

> I was proposing
> this option, because IIRC someone proposed or implied throwing away  
> the
> always_inline info by default.
>
> Devang, if I see this right, you agree with me that the combination  
> of 2) and
> b) are the "right" ones?

Yes. Otherwise, if we want to restrict enforcing always_inline across  
translation unit then we need to encode "always_inline in  module XYZ"  
in LLVM IR, not just "always_inline".
-
Devang