bpf: Remove builtin global functions #698
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Add #![no_builtins] to all test programs; see aya-rs/aya#698 for rationale.
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Add #![no_builtins] to all test programs; see aya-rs/aya#698 for rationale.
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See aya-rs/aya#698 for rationale.
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See aya-rs/aya#698 for rationale.
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The compiler-builtins fallbacks don't pass the verifier, which is why we provide our own |
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I don't think that's correct; if it were, the integration tests would fail here. |
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Ignore errors emitted on calls to builtins which are spurious. These builtins end up being lowered to libcalls to hidden functions, which are totally OK. See https://reviews.llvm.org/D155894 and aya-rs/aya#698 for some additional discussion. There doesn't seem to be a silver bullet here; BPF is fundamentally adversarial to these memory intrinsics. We can revisit this once we have DI and can more easily locate the source location that results in their inclusion.
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Add #![no_builtins] to all test programs; see aya-rs/aya#698 for rationale.
tamird
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Add #![no_builtins] to all test programs; see aya-rs/aya#698 for rationale.
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We've discussed this on discord, the tests are passing because of inlining. Can we close? |
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I'd still like to write better tests, marking as draft if that's ok. |
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See aya-rs/aya#698 for rationale.
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See aya-rs/aya#698 for rationale.
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@tamird, this pull request is now in conflict and requires a rebase. |
This commit removes memset and memcpy, relying instead on implementations provided by std/compiler-builtins. This commit adds `#![no_builtins]` to all the BPF programs written in Rust, and the same should be propagated to aya-template and all examples in the book and elsewhere before this commit is merged. It turns out that without the `#![no_builtins]` annotation rustc generates LLVM IR that calls LLVM intrinsics rather than libcalls. These may end up as libcalls after lowering, but not before emitting errors in BPF lowering[0]. This works thanks to rust-lang/rust#113716 which causes `#![no_builtins]` to behave similarly to `-fno-builtin` in clang, which was added in https://reviews.llvm.org/D68028 with similar motivation. This commit implies that we now require rustc nightly >= 2023-07-20. [0] https://github.com/llvm/llvm-project/blob/7b2745b/llvm/lib/Target/BPF/BPFISelLowering.cpp#L472-L474
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See aya-rs/aya#698 for rationale.
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See aya-rs/aya#698 for rationale.
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This commit removes memset and memcpy, relying instead on
implementations provided by std/compiler-builtins.
This commit adds
#![no_builtins]to all the BPF programs written inRust, and the same should be propagated to aya-template and all examples
in the book and elsewhere before this commit is merged.
It turns out that without the
#![no_builtins]annotation rustcgenerates LLVM IR that calls LLVM intrinsics rather than libcalls. These
may end up as libcalls after lowering, but not before emitting errors in
BPF lowering[0].
This works thanks to rust-lang/rust#113716 which
causes
#![no_builtins]to behave similarly to-fno-builtinin clang,which was added in https://reviews.llvm.org/D68028 with similar
motivation.
This commit implies that we now require rustc nightly >= 2023-07-20.
[0] https://github.com/llvm/llvm-project/blob/7b2745b/llvm/lib/Target/BPF/BPFISelLowering.cpp#L472-L474