https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107480
Bug ID: 107480
Summary: bpf: add __builtin_preserve_type_info
Product: gcc
Version: 13.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: david.faust at oracle dot com
Target Milestone: ---
LLVM supports a BPF builtin:
__builtin_preserve_type_info (param, flag)
which is used to generate additional relocations for the
Compile Once - Run Everywhere (CO-RE) mechanism.
This builtin produces a relocation recording the information
about the type of 'param', such as it's size or whether or
not it exists on the host kernel, according to 'flag'. This
information is returned to the program and patched by the
eBPF loader during loading.
We should support this functionality in GCC.
These are the relevant changes in LLVM:
https://reviews.llvm.org/D83878
https://reviews.llvm.org/D83242
