fix(values): support Box and Nullable nested inside aggregates in to_ptr

[TomerStarkware]

Stacked on #1655.

Problem

Value::to_ptr dispatched only on the Value variant, and Box<T> / Nullable<T> have no dedicated variant — so a box nested inside a struct, array, enum, or dict fell through to the payload's own arm and wrote the payload inline where the layout expects a single pointer, corrupting every following member. Only top-level boxes worked, via a dedicated AbiArgument arm.

Separately, that arm allocated the payload with libc_malloc, which leaked: boxes are arena-owned and never individually freed (see crate::libfuncs::box), so nothing ever released the block.

Fix

Handle both types by type before dispatching on the value: marshal the payload recursively, move it into the execution arena, and return a slot holding the payload pointer — the type's inline representation, matching from_ptr's Box/Nullable arms. Value::Null produces a slot holding a null pointer.

The AbiArgument Box/Nullable arms now delegate to this path and pass the pointer by value, removing the malloc leak and the Box/Nullable type_id inconsistency.

Tests

• Native execution: Nullable<bool> argument (null and both variants — a memory-allocated payload), and a Box<felt252> nested inside a struct argument.
• Round-trip unit tests: boxed bool, nullable bool (incl. null), struct with a boxed member.

🤖 Generated with Claude Code

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This change is 

[github-actions]

✅ Code is now correctly formatted.

[orizi]

@orizi reviewed 5 files and all commit messages, and made 1 comment.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on TomerStarkware).

[github-actions]

Benchmarking results

Benchmark for program dict_insert

Open benchmarks

Command	Mean [s]	Min [s]	Max [s]	Relative
Cairo-vm (Rust, Cairo 1)	8.600 ± 0.065	8.483	8.713	5.41 ± 0.07
cairo-native (embedded AOT)	1.589 ± 0.016	1.565	1.613	1.00
cairo-native (embedded JIT using LLVM's ORC Engine)	1.593 ± 0.015	1.568	1.615	1.00 ± 0.01

Benchmark for program dict_snapshot

Open benchmarks

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
Cairo-vm (Rust, Cairo 1)	449.2 ± 4.8	443.0	455.9	1.00
cairo-native (embedded AOT)	1385.1 ± 15.0	1365.5	1408.0	3.08 ± 0.05
cairo-native (embedded JIT using LLVM's ORC Engine)	1420.0 ± 21.9	1393.4	1450.5	3.16 ± 0.06

Benchmark for program factorial_2M

Open benchmarks

Command	Mean [s]	Min [s]	Max [s]	Relative
Cairo-vm (Rust, Cairo 1)	3.682 ± 0.079	3.626	3.880	2.55 ± 0.06
cairo-native (embedded AOT)	1.444 ± 0.008	1.430	1.456	1.00
cairo-native (embedded JIT using LLVM's ORC Engine)	1.460 ± 0.013	1.434	1.478	1.01 ± 0.01

Benchmark for program fib_2M

Open benchmarks

Command	Mean [s]	Min [s]	Max [s]	Relative
Cairo-vm (Rust, Cairo 1)	3.581 ± 0.011	3.555	3.595	2.55 ± 0.02
cairo-native (embedded AOT)	1.412 ± 0.011	1.387	1.425	1.00 ± 0.01
cairo-native (embedded JIT using LLVM's ORC Engine)	1.406 ± 0.008	1.397	1.420	1.00

Benchmark for program linear_search

Open benchmarks

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
Cairo-vm (Rust, Cairo 1)	481.1 ± 3.9	477.3	488.6	1.00
cairo-native (embedded AOT)	1412.1 ± 14.4	1390.1	1429.6	2.94 ± 0.04
cairo-native (embedded JIT using LLVM's ORC Engine)	1438.2 ± 16.6	1418.1	1467.4	2.99 ± 0.04

Benchmark for program logistic_map

Open benchmarks

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
Cairo-vm (Rust, Cairo 1)	412.7 ± 3.3	407.8	417.2	1.00
cairo-native (embedded AOT)	1401.9 ± 15.2	1376.8	1427.6	3.40 ± 0.05
cairo-native (embedded JIT using LLVM's ORC Engine)	1428.8 ± 15.3	1408.8	1456.2	3.46 ± 0.05

[github-actions]

Benchmark results Main vs HEAD.

Base

Command	Mean [s]	Min [s]	Max [s]	Relative
base dict_insert.cairo (JIT)	1.821 ± 0.014	1.805	1.842	1.01 ± 0.01
base dict_insert.cairo (AOT)	1.803 ± 0.008	1.792	1.817	1.00

Head

Command	Mean [s]	Min [s]	Max [s]	Relative
head dict_insert.cairo (JIT)	1.921 ± 0.031	1.888	1.991	1.00
head dict_insert.cairo (AOT)	1.922 ± 0.023	1.888	1.964	1.00 ± 0.02

Base

Command	Mean [s]	Min [s]	Max [s]	Relative
base dict_snapshot.cairo (JIT)	1.639 ± 0.011	1.626	1.664	1.01 ± 0.01
base dict_snapshot.cairo (AOT)	1.615 ± 0.015	1.602	1.656	1.00

Head

Command	Mean [s]	Min [s]	Max [s]	Relative
head dict_snapshot.cairo (JIT)	1.754 ± 0.026	1.705	1.788	1.01 ± 0.02
head dict_snapshot.cairo (AOT)	1.736 ± 0.022	1.691	1.768	1.00

Base

Command	Mean [s]	Min [s]	Max [s]	Relative
base factorial_2M.cairo (JIT)	1.697 ± 0.008	1.683	1.711	1.01 ± 0.01
base factorial_2M.cairo (AOT)	1.681 ± 0.009	1.668	1.697	1.00

Head

Command	Mean [s]	Min [s]	Max [s]	Relative
head factorial_2M.cairo (JIT)	1.801 ± 0.013	1.785	1.822	1.01 ± 0.01
head factorial_2M.cairo (AOT)	1.782 ± 0.020	1.754	1.808	1.00

Base

Command	Mean [s]	Min [s]	Max [s]	Relative
base fib_2M.cairo (JIT)	1.648 ± 0.007	1.634	1.660	1.02 ± 0.01
base fib_2M.cairo (AOT)	1.610 ± 0.011	1.599	1.634	1.00

Head

Command	Mean [s]	Min [s]	Max [s]	Relative
head fib_2M.cairo (JIT)	1.767 ± 0.021	1.740	1.809	1.02 ± 0.03
head fib_2M.cairo (AOT)	1.726 ± 0.044	1.629	1.778	1.00

Base

Command	Mean [s]	Min [s]	Max [s]	Relative
base linear_search.cairo (JIT)	1.663 ± 0.008	1.651	1.681	1.02 ± 0.01
base linear_search.cairo (AOT)	1.636 ± 0.009	1.616	1.647	1.00

Head

Command	Mean [s]	Min [s]	Max [s]	Relative
head linear_search.cairo (JIT)	1.794 ± 0.027	1.763	1.834	1.03 ± 0.02
head linear_search.cairo (AOT)	1.740 ± 0.018	1.716	1.780	1.00

Base

Command	Mean [s]	Min [s]	Max [s]	Relative
base logistic_map.cairo (JIT)	1.642 ± 0.008	1.630	1.659	1.01 ± 0.01
base logistic_map.cairo (AOT)	1.626 ± 0.018	1.610	1.666	1.00

Head

Command	Mean [s]	Min [s]	Max [s]	Relative
head logistic_map.cairo (JIT)	1.747 ± 0.018	1.717	1.769	1.01 ± 0.02
head logistic_map.cairo (AOT)	1.722 ± 0.022	1.690	1.755	1.00