moved boxes and nullables to arena

[TomerStarkware]

#Move Box and Nullable allocations to a per-invocation arena

Replace individual realloc/free calls for Box and Nullable allocations with a thread-local bumpalo arena that is reset once per program invocation.

• New runtime function cairo_native__box_alloc(size, align) allocates out of a thread-local Bump arena, registered as the BoxAlloc runtime binding (src/runtime.rs,
  src/metadata/runtime_bindings.rs).
• invoke_dynamic calls cairo_native__reset_box_arena() after the trampoline returns, freeing all box/nullable memory allocated during that invocation in one shot
  (src/executor.rs).
• Libfuncs (box, const, enum::boxed_match, struct::boxed_deconstruct) now route all box allocations through into_box → RuntimeBindingsMeta::box_alloc, and no longer emit
  free on unbox / boxed_match / span_from_tuple.
• types/box.rs and types/nullable.rs:
  • Dup now uses the arena instead of realloc and is only registered when the inner type actually has a dup override (the pure-memcpy path is gone).
  • Drop is only registered when the inner type has a drop override; the trailing free is removed since arena memory is reclaimed at invocation end.
• Value::from_ptr no longer libc_frees the inner pointer for Box/Nullable payloads.

Introduces Breaking Changes?

No

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This change is 

[github-actions]

Benchmarking results

Benchmark for program dict_insert

Open benchmarks

Command	Mean [s]	Min [s]	Max [s]	Relative
Cairo-vm (Rust, Cairo 1)	11.191 ± 0.091	11.109	11.423	5.75 ± 0.06
cairo-native (embedded AOT)	1.945 ± 0.011	1.925	1.961	1.00
cairo-native (embedded JIT using LLVM's ORC Engine)	2.031 ± 0.017	2.001	2.057	1.04 ± 0.01

Benchmark for program dict_snapshot

Open benchmarks

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
Cairo-vm (Rust, Cairo 1)	530.8 ± 5.5	524.1	540.2	1.00
cairo-native (embedded AOT)	1640.3 ± 12.5	1622.0	1662.2	3.09 ± 0.04
cairo-native (embedded JIT using LLVM's ORC Engine)	1756.6 ± 18.0	1727.8	1779.4	3.31 ± 0.05

Benchmark for program factorial_2M

Open benchmarks

Command	Mean [s]	Min [s]	Max [s]	Relative
Cairo-vm (Rust, Cairo 1)	4.951 ± 0.068	4.898	5.061	2.36 ± 0.04
cairo-native (embedded AOT)	2.098 ± 0.012	2.079	2.120	1.00
cairo-native (embedded JIT using LLVM's ORC Engine)	2.145 ± 0.019	2.113	2.177	1.02 ± 0.01

Benchmark for program fib_2M

Open benchmarks

Command	Mean [s]	Min [s]	Max [s]	Relative
Cairo-vm (Rust, Cairo 1)	4.821 ± 0.045	4.797	4.949	2.97 ± 0.04
cairo-native (embedded AOT)	1.625 ± 0.012	1.611	1.653	1.00
cairo-native (embedded JIT using LLVM's ORC Engine)	1.698 ± 0.017	1.673	1.727	1.04 ± 0.01

Benchmark for program linear_search

Open benchmarks

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
Cairo-vm (Rust, Cairo 1)	567.9 ± 2.1	565.0	571.3	1.00
cairo-native (embedded AOT)	1696.3 ± 18.0	1660.8	1720.7	2.99 ± 0.03
cairo-native (embedded JIT using LLVM's ORC Engine)	1823.0 ± 22.7	1784.6	1859.4	3.21 ± 0.04

Benchmark for program logistic_map

Open benchmarks

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
Cairo-vm (Rust, Cairo 1)	483.4 ± 6.6	477.8	496.0	1.00
cairo-native (embedded AOT)	1800.3 ± 15.3	1780.9	1831.3	3.72 ± 0.06
cairo-native (embedded JIT using LLVM's ORC Engine)	1987.8 ± 18.8	1961.1	2016.5	4.11 ± 0.07

[github-actions]

Benchmark results Main vs HEAD.

Base

Command	Mean [s]	Min [s]	Max [s]	Relative
base dict_insert.cairo (JIT)	1.934 ± 0.031	1.899	2.001	1.03 ± 0.02
base dict_insert.cairo (AOT)	1.870 ± 0.023	1.829	1.905	1.00

Head

Command	Mean [s]	Min [s]	Max [s]	Relative
head dict_insert.cairo (JIT)	2.139 ± 0.016	2.117	2.164	1.03 ± 0.01
head dict_insert.cairo (AOT)	2.075 ± 0.023	2.039	2.111	1.00

Base

Command	Mean [s]	Min [s]	Max [s]	Relative
base dict_snapshot.cairo (JIT)	1.685 ± 0.019	1.658	1.714	1.07 ± 0.02
base dict_snapshot.cairo (AOT)	1.568 ± 0.016	1.549	1.601	1.00

Head

Command	Mean [s]	Min [s]	Max [s]	Relative
head dict_snapshot.cairo (JIT)	1.828 ± 0.015	1.801	1.849	1.08 ± 0.02
head dict_snapshot.cairo (AOT)	1.688 ± 0.020	1.660	1.717	1.00

Base

Command	Mean [s]	Min [s]	Max [s]	Relative
base factorial_2M.cairo (JIT)	2.056 ± 0.015	2.038	2.089	1.03 ± 0.01
base factorial_2M.cairo (AOT)	1.999 ± 0.022	1.970	2.031	1.00

Head

Command	Mean [s]	Min [s]	Max [s]	Relative
head factorial_2M.cairo (JIT)	2.160 ± 0.017	2.127	2.188	1.03 ± 0.01
head factorial_2M.cairo (AOT)	2.096 ± 0.014	2.074	2.114	1.00

Base

Command	Mean [s]	Min [s]	Max [s]	Relative
base fib_2M.cairo (JIT)	1.630 ± 0.021	1.591	1.657	1.03 ± 0.02
base fib_2M.cairo (AOT)	1.581 ± 0.021	1.557	1.624	1.00

Head

Command	Mean [s]	Min [s]	Max [s]	Relative
head fib_2M.cairo (JIT)	1.706 ± 0.012	1.688	1.722	1.04 ± 0.01
head fib_2M.cairo (AOT)	1.644 ± 0.014	1.626	1.677	1.00

Base

Command	Mean [s]	Min [s]	Max [s]	Relative
base linear_search.cairo (JIT)	1.739 ± 0.014	1.721	1.763	1.08 ± 0.01
base linear_search.cairo (AOT)	1.609 ± 0.014	1.586	1.632	1.00

Head

Command	Mean [s]	Min [s]	Max [s]	Relative
head linear_search.cairo (JIT)	1.817 ± 0.014	1.792	1.837	1.08 ± 0.01
head linear_search.cairo (AOT)	1.681 ± 0.011	1.659	1.698	1.00

Base

Command	Mean [s]	Min [s]	Max [s]	Relative
base logistic_map.cairo (JIT)	1.885 ± 0.019	1.848	1.913	1.10 ± 0.01
base logistic_map.cairo (AOT)	1.720 ± 0.012	1.702	1.736	1.00

Head

Command	Mean [s]	Min [s]	Max [s]	Relative
head logistic_map.cairo (JIT)	1.987 ± 0.017	1.970	2.029	1.10 ± 0.01
head logistic_map.cairo (AOT)	1.811 ± 0.012	1.796	1.831	1.00

[orizi]

@orizi reviewed 1 file and all commit messages, and made 1 comment.
Reviewable status: 1 of 11 files reviewed, 1 unresolved discussion (waiting on TomerStarkware).

---

src/executor.rs line 355 at r1 (raw file):

    builtin_stats.blake = BLAKE_CALL_COUNT.with(|c| c.replace(0)) as usize;

    // Reset the box arena to free all allocated memory.

maybe this entire bump object be just stored in metadata or something of that sort?

[orizi]

@orizi reviewed 17 files and all commit messages, made 1 comment, and resolved 1 discussion.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on TomerStarkware).

---

src/libfuncs/array.rs line 206 at r3 (raw file):

    )?)?;

    // Move the data into the array and free the original tuple. Since the tuple and the array are

fix doc.

make sure next PR removes almost all memcopies.

[TomerStarkware]

@TomerStarkware made 1 comment.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on orizi).

---

src/libfuncs/array.rs line 206 at r3 (raw file):

Previously, orizi wrote…

fix doc.

make sure next PR removes almost all memcopies.

Done.

[orizi]

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

[orizi]

@orizi reviewed 3 files and all commit messages, and made 1 comment.
Reviewable status: 16 of 17 files reviewed, all discussions resolved (waiting on TomerStarkware).

[orizi]

@orizi reviewed 1 file.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on TomerStarkware).