llvm-project

accec8b9 - [lld][macho] Move unwind logic from equalsVariable to equalsConstant (#165325)

[lld][macho] Move unwind logic from equalsVariable to equalsConstant (#165325) Since equalsVariable runs a lot more times, we want to minimize the work it needs to do. Anything not dependent on the icfEqClass values should get hoisted out. With this change, ICF runs ~1.7% faster when linking clang. Benchmarking approach: cbdr sample -b ~/extract-icf-time.sh ~/old/ld64.lld bin/ld64.lld --timeout=300s | cbdr analyze -s 95 `extract-icf-time.sh` runs the clang link command with the `--icf=all --time-trace` flags, then parses out the ICF duration from the resulting time trace using `jq`: jq '{ICF: (.traceEvents[] | select(.name == "Fold Identical Code Sections") | .dur)}' Output: </Users/jezng/extract-icf-time.sh ["/Users/jezng/old/ld64.lld"]> </Users/jezng/extract-icf-time.sh ["bin/ld64.lld"]> difference (95% CI) ICF 83678.207 ± 1502.778 82234.751 ± 1290.984 [ -2.0% .. -1.4%] samples 208 225