[PATCH] D17212: [ThinLTO] Support for call graph in per-module and combined summary.

[Teresa Johnson via llvm-commits]

tejohnson added a comment.

In http://reviews.llvm.org/D17212#362994, @davidxl wrote:

> Is there a need to mark it? Does the following work?
>
> 1. using summary call graph to do importing decision
> 2. for any function that is imported by another module, mark it as 'exported'
> 3. When processing the exporting module, check any exported function and promote any statics it references.
>
>   David


That does work for correctness, but Mehdi was proposing that functions accessing local values need to meet a higher importing threshold so that we don't cause too many promotions due to over-eager importing.

In terms of serializing the info out for doing any of this with a distributed build, we could do it via an "exported" bit in the combined summary though.


http://reviews.llvm.org/D17212