Hi! This small set is the first step to dead code elimination I'm working on, but it stands on its own. I want to make the verifier understand JSET instruction better so we can remove some trivial dead code optimizations from the nfp JIT.
First patch adds a functional test for JSET, because AFAICT LLVM does not generate that instruction so JITs probably don't get well tested. Second patch make the verifier understand JSET in the same way it already understands all the other conditional jump instructions. Last but not least the test cases for patch 2. Jakub Kicinski (3): selftests: bpf: add trivial JSET test bpf: verifier: teach the verifier to reason about the BPF_JSET instruction selftests: bpf: verifier: add tests for JSET interpretation kernel/bpf/verifier.c | 20 +++++ tools/testing/selftests/bpf/test_progs.c | 69 +++++++++++++++ tools/testing/selftests/bpf/test_verifier.c | 96 +++++++++++++++++++++ 3 files changed, 185 insertions(+) -- 2.17.1