Return owned results from the optimizer and log every parent rewrite

[robert3005]

try_optimize and try_optimize_recursive borrowed the array and returned
Option, so callers cloned the input again on a miss. They now
take the array by value and return it with a flag that says whether any
rewrite fired.

The executor logged execute_parent rewrites in two places with the same
format and did not log reduce_parent rewrites. A log_parent_rewrite
helper now logs both, with the phase name in the message.

[codspeed]

Merging this PR will degrade performance by 7.34%

⚠️ 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.

⚠️ 1 benchmark measured no execution time

Nothing ran under measurement, usually because the compiler removed the code under test. This result is not comparable, so it counts as unchanged.

Preventing compiler optimizations

⚠️ Different runtime environments detected

Some benchmarks with significant performance changes were compared across different runtime environments,
which may affect the accuracy of the results.

Open the report in CodSpeed to investigate

⚡ 3 improved benchmarks
❌ 4 regressed benchmarks
✅ 2168 untouched benchmarks
⏩ 534 skipped benchmarks¹

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	Simulation	density_sweep_dense_runs[0.001]	30.2 µs	47.5 µs	-36.4%
❌	Simulation	filter_powerlaw_by_mostly_true[250000]	104 µs	149.5 µs	-30.43%
❌	Simulation	take[routing/same_chunk/primitive/nonnull/chunks=32/indices=1000]	176 µs	225.6 µs	-21.97%
❌	WallTime	starts_with_avx2[8, VarBin]	41.2 µs	46.9 µs	-12.07%
⚡	WallTime	mul_u64_nonnull_neon	40.2 µs	28.7 µs	+40%
⚡	WallTime	multiply_shapes_neon[(32768, PerRowPerRow)]	38.3 µs	32.6 µs	+17.47%
⚡	WallTime	mul_i64_nonnull_neon	38.4 µs	32.7 µs	+17.47%
⚠️	Simulation	bench_compare_primitive[(10000, 2)]	64.2 µs	< 1 ns	N/A

Tip

Investigate this regression by commenting @codspeedbot fix this regression on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing rk/optimize-owned (cbdec56) with develop (88a4de8)}

Footnotes

1. 534 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. ↩