zp-bool-array — bool-array
Claim
[]bool count vs bit_set.Static.count under Zig 0.17.0 -Ofast on this Linux machine shows a clear before/after wall-clock gap.
How measured
- Harness:
packages/zperf/examples/bench/evidence_fill.zig(rulezp-bool-arraycases) - Build:
zig build-exe -Ofast· optimize_mode=fast - Timing:
Io.Clockawake; warm=2; median of 9 rounds - before:
bool_array_count - after:
bitset_count - ops=524288
- Raw:
zp-bool-array.jsonl
Runtime (this evidence file)
| Field | Value |
|---|---|
| When | 2026-10-21 Asia/Shanghai (JSONL ts is UTC) |
| Zig | 0.17.0 · fast |
| Median before | ~0.08908 ms |
| Median after | ~0.002937 ms |
| ratio before/after | ~30.3× |
Lint mapping
zperf-lint zp-bool-array / bool-array. Default severity in rules.zig is off (the CLI does not report the rule); see evidence-policy for keep/escalate. Evidence exists and agrees directionally.
Verdict
Agree ~30.3× for popcount-style walk (and 8× denser).
Limits
Per-element addressability / concurrent bit writes may need []bool.