[llvm-branch-commits] Add pointer field protection feature. (PR #133538)

[Oliver Hunt via llvm-branch-commits]

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@@ -928,6 +936,11 @@ namespace {
       if (PointerAuthQualifier Q = F->getType().getPointerAuth();
           Q && Q.isAddressDiscriminated())
         return false;
+      // Non-trivially-copyable fields with pointer field protection need to be
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ojhunt wrote:

This is an example of the code I was thinking of when I talked about sharing code with PointerAuth, the PFP and pointer auth code is essentially identical here.

Essentially any place that interacts with a pointer auth qualifier should also have PFP code, and the code is going to be (at the place of interaction, not the underlying implementation) going to be essentially the same.

https://github.com/llvm/llvm-project/pull/133538