perf(fastlanes): Evaluate constant list membership

[lwwmanning]

Evaluate constant integer list membership directly against BitPacked arrays. Lists with one to four members use fused comparisons. Larger lists with spans up to 4 KiB use a byte lookup table during FastLanes unpack. Wider spans decode once and reuse the prepared sorted membership plan. A Primitive kernel provides the optimized canonical fallback. Empty lists return false for null needles. Non-empty lists preserve needle validity, and null lists return null.

Local benchmarks cover 64, 1,024, and 65,536 values across 1, 4, 8, 32, and 64 list members. Compressed execution was 21–54% faster than canonical fallback. Tables near the 4 KiB cap were 20–35% faster. Wide sparse sets were 10–16% faster at 1,024 rows and stayed within 1% at 65,536 rows.

🤖 Generated with Codex

[codspeed-hq]

Merging this PR will degrade performance by 8.8%

⚠️ Unknown Walltime execution environment detected

Using the Walltime instrument on standard Hosted Runners will lead to inconsistent data.

For the most accurate results, we recommend using CodSpeed Macro Runners: bare-metal machines fine-tuned for performance measurement consistency.

⚡ 3 improved benchmarks
❌ 15 regressed benchmarks
✅ 2072 untouched benchmarks
🆕 141 new benchmarks
⏩ 206 skipped benchmarks¹
🗄️ 4 archived benchmarks run²

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	WallTime	arrow_checked_add_u32_neon[16384]	13.4 µs	20.3 µs	-34.04%
❌	Simulation	filter_powerlaw_by_mostly_true[250000]	186.1 µs	215.9 µs	-13.79%
❌	Simulation	filter_random_by_mostly_true[250000]	186.2 µs	215.9 µs	-13.77%
❌	Simulation	filter_random_by_random[250000]	170.4 µs	193.9 µs	-12.11%
❌	Simulation	filter_powerlaw_by_random[250000]	170.5 µs	194 µs	-12.11%
❌	Simulation	density_sweep_random[0.9]	92 µs	104 µs	-11.47%
❌	Simulation	filter_powerlaw_by_mostly_true[100000]	93.2 µs	105.1 µs	-11.35%
❌	Simulation	filter_random_by_mostly_true[100000]	92.8 µs	104.6 µs	-11.34%
❌	Simulation	density_sweep_random[0.95]	92.6 µs	104.5 µs	-11.33%
❌	Simulation	density_sweep_dense_runs[0.9]	92.1 µs	103.8 µs	-11.28%
❌	Simulation	density_sweep_dense_runs[0.95]	92.8 µs	104.5 µs	-11.18%
❌	Simulation	filter_powerlaw_by_power_law[250000]	160.9 µs	179.8 µs	-10.48%
❌	Simulation	filter_random_by_power_law[250000]	160.8 µs	179.5 µs	-10.47%
❌	WallTime	mul_i32_nonnull_avx512	7.1 µs	8 µs	-10.45%
❌	WallTime	mul_u32_nonnull_avx512	5.7 µs	6.3 µs	-10.41%
⚡	WallTime	arrow_checked_add_u32_avx512[16384]	21.4 µs	17.7 µs	+21.02%
⚡	WallTime	arrow_checked_add_u32_avx2[16384]	21.3 µs	17.7 µs	+20.4%
⚡	Simulation	compress_fsst[(500, 64, 4)]	488.3 µs	442.2 µs	+10.43%
🆕	WallTime	packed_current_neon[decode_u16_m25_u16_w8_n65536]	N/A	373.6 µs	N/A
🆕	WallTime	packed_current_neon[decode_u32_m13_u32_w8_n65536]	N/A	249.9 µs	N/A
...	...	...	...	...	...

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Tip

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_{Comparing wm/fastlanes-list-contains (cc5bbc0) with develop (eff83d4)}

Footnotes

1. 206 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

2. 4 benchmarks were run, but are now archived. If they were deleted in another branch, consider rebasing to remove them from the report. Instead if they were added back, click here to restore them. ↩