[PATCH] D123800: [BPF] handle opaque-pointer for __builtin_preserve_enum_value

[Yonghong Song via Phabricator via llvm-commits]

yonghong-song added a comment.

In D123800#3452076 <https://reviews.llvm.org/D123800#3452076>, @ast wrote:

> The fix to prevent the crash looks good, but what should be the expected codegen for a global variable?
> CO-RE needs a constant.
> Are we assuming that the global data will be inited with some constant and a later pass will propagate it further into __builtin_preserve,
> so at the end it will become a constant?

Right. These global variables are encoding enum Name/Value information and later the actual generated code for the builtin will be the enum value
as the intrinsic __builtin_preserve_enum_value() returns the enum value, but a relocation record is also generated so libbpf can change
the enum value in the code in case "enum name -> enum value" changed.


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https://reviews.llvm.org/D123800