Specialize lookup scans with unsafe buffers

[dduan]

Replace hot lookup loops in Parser with @inline pointer scans over index lists and key-pair storage. Split keyed and unkeyed table lookup paths to avoid shared table extraction and route tableValue/lookupTable/lookupArray through the new match helpers.

[github-actions]

Comparing results between 'main' and 'pull_request'

Host 'runnervmwffz4' with 4 'x86_64' processors with 15 GB memory, running:
#18~24.04.1-Ubuntu SMP Sat Jun 28 04:46:03 UTC 2025

TOMLDecoderBenchmarks

Decode toml.io example metrics

Time (wall clock): results within specified thresholds, fold down for details.

Time (wall clock) (μs) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	66	68	68	68	69	77	135	9038
pull_request	67	68	68	69	70	78	114	9032
Δ	1	0	0	1	1	1	-21	-6
Improvement %	-2	0	0	-1	-1	-1	16	-6

Retains: results within specified thresholds, fold down for details.

Retains *	p0	p25	p50	p75	p90	p99	p100	Samples
main	597	597	597	598	598	598	598	9038
pull_request	596	596	596	597	597	597	597	9032
Δ	-1	-1	-1	-1	-1	-1	-1	-6
Improvement %	0	0	0	0	0	0	0	-6

Parse toml.io example metrics

Time (wall clock): results within specified thresholds, fold down for details.

Time (wall clock) (ns) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	5013	5187	5235	5299	5395	8591	21757	10000
pull_request	5134	5323	5379	5447	5551	7131	37096	10000
Δ	121	136	144	148	156	-1460	15339	0
Improvement %	-2	-3	-3	-3	-3	17	-71	0

Retains: results within specified thresholds, fold down for details.

Retains *	p0	p25	p50	p75	p90	p99	p100	Samples
main	5	6	6	6	6	6	6	10000
pull_request	5	6	6	6	6	6	6	10000
Δ	0	0	0	0	0	0	0	0
Improvement %	0	0	0	0	0	0	0	0

decode canada.toml metrics

Time (wall clock): results within specified thresholds, fold down for details.

Time (wall clock) (ms) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	263	263	264	265	267	267	267	4
pull_request	259	259	260	260	260	260	260	4
Δ	-4	-4	-4	-5	-7	-7	-7	0
Improvement %	2	2	2	2	3	3	3	0

Retains: results within specified thresholds, fold down for details.

Retains (K) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	1674	1674	1674	1674	1674	1674	1674	4
pull_request	1674	1674	1674	1674	1674	1674	1674	4
Δ	0	0	0	0	0	0	0	0
Improvement %	0	0	0	0	0	0	0	0

decode twitter.toml metrics

Time (wall clock): results within specified thresholds, fold down for details.

Time (wall clock) (μs) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	8417	8454	8479	8503	8536	9134	9719	117
pull_request	8640	8684	8700	8724	8749	8978	9218	115
Δ	223	230	221	221	213	-156	-501	-2
Improvement %	-3	-3	-3	-3	-2	2	5	-2

Retains: results within specified thresholds, fold down for details.

Retains (K) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	66	66	66	66	66	66	66	117
pull_request	66	66	66	66	66	66	66	115
Δ	0	0	0	0	0	0	0	-2
Improvement %	0	0	0	0	0	0	0	-2

parse GitHub events archive metrics

Time (wall clock): results within specified thresholds, fold down for details.

Time (wall clock) (ms) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	155	155	156	157	159	159	159	7
pull_request	154	156	157	157	158	158	158	7
Δ	-1	1	1	0	-1	-1	-1	0
Improvement %	1	-1	-1	0	1	1	1	0

Retains: results within specified thresholds, fold down for details.

Retains (K) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	77	77	77	77	77	77	77	7
pull_request	77	77	77	77	77	77	77	7
Δ	0	0	0	0	0	0	0	0
Improvement %	0	0	0	0	0	0	0	0

parse canada.toml metrics

Time (wall clock): results within specified thresholds, fold down for details.

Time (wall clock) (ms) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	15	15	16	17	17	19	19	63
pull_request	15	16	16	17	17	19	19	62
Δ	0	1	0	0	0	0	0	-1
Improvement %	0	-7	0	0	0	0	0	-1

Retains: results within specified thresholds, fold down for details.

Retains *	p0	p25	p50	p75	p90	p99	p100	Samples
main	129	130	130	130	130	130	130	63
pull_request	129	130	130	130	130	130	130	62
Δ	0	0	0	0	0	0	0	-1
Improvement %	0	0	0	0	0	0	0	-1

parse twitter.toml metrics

Time (wall clock): results within specified thresholds, fold down for details.

Time (wall clock) (μs) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	2354	2370	2376	2386	2394	2437	2834	414
pull_request	2354	2367	2374	2382	2392	2468	2784	414
Δ	0	-3	-2	-4	-2	31	-50	0
Improvement %	0	0	0	0	0	-1	2	0

Retains: results within specified thresholds, fold down for details.

Retains *	p0	p25	p50	p75	p90	p99	p100	Samples
main	1289	1290	1290	1290	1290	1290	1290	414
pull_request	1289	1290	1290	1290	1290	1290	1290	414
Δ	0	0	0	0	0	0	0	0
Improvement %	0	0	0	0	0	0	0	0