fix(ssa): Constant fold Brillig calls using the SSA interpreter

[vezenovm]

Description

Problem*

Alternative to #9365

Resolves #9015
Resolves #9097
Resolves #9484 (comment) (same error as #9097)
Resolves a panic from a Noir sync when attempting to debug log an array value (the same error as #9097)

Let's take the snippet from #9097:

fn main() {
    // Safety:
    let result = unsafe { foo([0]) };
    println(result);
}

unconstrained fn foo(bytes: [u8; 1]) -> Field {
    for _ in 0..bytes.len() {
        let _ = bytes[0];
    }
    0
}

We can see the following SSA when we fold constants with Brillig:

Details

After Inlining Brillig Calls (1) (step 42):
acir(inline) impure fn main f0 {
  b0():
    v1 = make_array [u8 0] : [u8; 1]                    // src/main.nr:3:32
    call f2(u1 1, Field 0)                              // std/lib.nr:40:9
    return
}
brillig(inline) predicate_pure fn foo f1 {
  b0(v0: [u8; 1]):
    inc_rc v0                                           // src/main.nr:8:17
    return Field 0
}
brillig(inline) impure fn print_unconstrained f2 {
  b0(v0: u1, v1: Field):
    v13 = make_array b"{\"kind\":\"field\"}"            // std/lib.nr:40:9
    call print(v0, v1, v13, u1 0)                       // std/lib.nr:34:5
    return
}

Remove Unreachable Instructions (2) (step 43): 0 ms
After Remove Unreachable Instructions (2) (step 43):
acir(inline) impure fn main f0 {
  b0():
    v1 = make_array [u8 0] : [u8; 1]                    // src/main.nr:3:32
    call f1(u1 1, Field 0)                              // std/lib.nr:40:9
    return
}
brillig(inline) predicate_pure fn print_unconstrained f1 {
  b0(v0: u1, v1: Field):
    v13 = make_array b"{\"kind\":\"field\"}"            // std/lib.nr:40:9
    call print(v0, v1, v13, u1 0)                       // std/lib.nr:34:5
    return
}

We can see that one Brillig function was folding into f0. However, the print remains. However, the Brillig context structure contains all the artifacts already has a set mapping for function ids to Brillig artifacts. Thus, when we remove functions after Brillig gen and change their IDs (e.g., like when normalizing) we end up fetching an artifact for the wrong function when it comes times to generate an entry point.

Summary*

Alternative to #9365. I realized we were already cloning all Brillig functions in fold_constants_with_brillig. In this version I simply changed the interface of the SSA interpreter to allow passing a mapping of functions instead of the entire SSA. This enables us to fold Brillig calls as part of constant_folding which avoids some of the regressions (both in bytecode size and compilation time) from #9365. Folding Brillig calls as part of constant_folding allows us to access new constants that get exposed during the execution of the pass.

This issue could have been fixed for #9097 by simply updating the IDs point to the Brillig artifacts as part of normalization. However, this felt brittle and I felt the problem laid out above still feels like it could come up elsewhere.

Aside the benefit of avoiding extra Brillig compilation, switching to using the SSA interpreter for constant folding Brillig entry points also avoids these kinds of situations where Brillig context needs to be updated due to secondary SSA passes post Brillig gen.

Additional Context

Documentation*

Check one:

• No documentation needed.
• Documentation included in this PR.
• [For Experimental Features] Documentation to be submitted in a separate PR.

PR Checklist*

• I have tested the changes locally.
• I have formatted the changes with Prettier and/or cargo fmt on default settings.

[github-actions]

Changes to number of Brillig opcodes executed

Generated at commit: 15563b669e333121ae89ed2f221411cde2b16276, compared to commit: b544e60a27e467d9eea6bd0e172b8f2b0d33c0d3

🧾 Summary (10% most significant diffs)

Program	Brillig opcodes (+/-)	%
higher_order_functions_inliner_zero	-15 ✅	-1.16%
global_var_regression_simple_inliner_max	-1 ✅	-3.23%
global_var_regression_simple_inliner_zero	-1 ✅	-3.23%

---

Full diff report 👇

Program	Brillig opcodes (+/-)	%
poseidon_bn254_hash_width_3_inliner_max	137,347 (+234)	+0.17%
regression_5252_inliner_max	760,008 (+1,200)	+0.16%
poseidonsponge_x5_254_inliner_max	152,905 (+240)	+0.16%
poseidon_bn254_hash_width_3_inliner_zero	167,759 (+234)	+0.14%
hashmap_inliner_min	79,946 (+15)	+0.02%
hashmap_inliner_zero	71,474 (+12)	+0.02%
uhashmap_inliner_zero	164,286 (+15)	+0.01%
uhashmap_inliner_min	174,340 (+15)	+0.01%
array_oob_regression_7965_inliner_max	313 (-1)	-0.32%
array_oob_regression_7965_inliner_min	313 (-1)	-0.32%
array_oob_regression_7965_inliner_zero	313 (-1)	-0.32%
nested_array_dynamic_inliner_min	2,826 (-10)	-0.35%
nested_array_dynamic_inliner_zero	2,826 (-10)	-0.35%
nested_array_dynamic_inliner_max	2,642 (-10)	-0.38%
global_consts_inliner_max	1,369 (-6)	-0.44%
global_consts_inliner_zero	1,369 (-6)	-0.44%
higher_order_functions_inliner_zero	1,276 (-15)	-1.16%
global_var_regression_simple_inliner_max	30 (-1)	-3.23%
global_var_regression_simple_inliner_zero	30 (-1)	-3.23%

[github-actions]

Changes to Brillig bytecode sizes

Generated at commit: 15563b669e333121ae89ed2f221411cde2b16276, compared to commit: b544e60a27e467d9eea6bd0e172b8f2b0d33c0d3

🧾 Summary (10% most significant diffs)

Program	Brillig opcodes (+/-)	%
global_var_regression_simple_inliner_max	-1 ✅	-2.56%
global_var_regression_simple_inliner_zero	-1 ✅	-2.56%
global_consts_inliner_max	-6 ✅	-2.99%
global_consts_inliner_zero	-6 ✅	-2.99%
binary_operator_overloading_inliner_max	-26 ✅	-6.99%

---

Full diff report 👇

Program	Brillig opcodes (+/-)	%
hashmap_inliner_zero	7,973 (-3)	-0.04%
uhashmap_inliner_min	7,425 (-6)	-0.08%
uhashmap_inliner_zero	6,939 (-6)	-0.09%
hashmap_inliner_min	9,325 (-9)	-0.10%
higher_order_functions_inliner_min	1,605 (-2)	-0.12%
nested_array_in_slice_inliner_min	807 (-2)	-0.25%
nested_array_in_slice_inliner_zero	807 (-2)	-0.25%
nested_array_in_slice_inliner_max	947 (-3)	-0.32%
regression_11294_inliner_min	302 (-1)	-0.33%
array_oob_regression_7965_inliner_max	259 (-2)	-0.77%
array_oob_regression_7965_inliner_min	259 (-2)	-0.77%
array_oob_regression_7965_inliner_zero	259 (-2)	-0.77%
nested_array_dynamic_inliner_max	1,719 (-15)	-0.87%
nested_array_dynamic_inliner_min	1,427 (-15)	-1.04%
nested_array_dynamic_inliner_zero	1,427 (-15)	-1.04%
regression_9538_inliner_max	94 (-1)	-1.05%
regression_9538_inliner_min	94 (-1)	-1.05%
regression_9538_inliner_zero	94 (-1)	-1.05%
higher_order_functions_inliner_zero	732 (-15)	-2.01%
global_var_regression_simple_inliner_max	38 (-1)	-2.56%
global_var_regression_simple_inliner_zero	38 (-1)	-2.56%
global_consts_inliner_max	195 (-6)	-2.99%
global_consts_inliner_zero	195 (-6)	-2.99%
binary_operator_overloading_inliner_max	346 (-26)	-6.99%

[github-actions]

⚠️ Performance Alert ⚠️

Possible performance regression was detected for benchmark 'Test Suite Duration'.
Benchmark result of this commit is worse than the previous benchmark result exceeding threshold 1.20.

Benchmark suite	Current: ad2a326	Previous: b544e60	Ratio
test_report_noir-lang_noir_bigcurve_	347 s	279 s	1.24

This comment was automatically generated by workflow using github-action-benchmark.

CC: @TomAFrench

[github-actions]

ACVM Benchmarks

Benchmark suite	Current: ad2a326	Previous: b544e60	Ratio
purely_sequential_opcodes	249850 ns/iter (± 674)	248430 ns/iter (± 776)	1.01
perfectly_parallel_opcodes	218077 ns/iter (± 3815)	218561 ns/iter (± 6896)	1.00
perfectly_parallel_batch_inversion_opcodes	2778732 ns/iter (± 2207)	2782471 ns/iter (± 11623)	1.00

This comment was automatically generated by workflow using github-action-benchmark.

[github-actions]

Execution Time

Benchmark suite	Current: ad2a326	Previous: b544e60	Ratio
private-kernel-inner	0.014 s	0.019 s	0.74
private-kernel-reset	0.155 s	0.153 s	1.01
private-kernel-tail	0.01 s	0.01 s	1
rollup-base-private	0.267 s	0.264 s	1.01
rollup-base-public	0.162 s	0.164 s	0.99
rollup-block-root	12.9 s	12.9 s	1
rollup-merge	0.002 s	0.002 s	1
rollup-root	0.004 s	0.004 s	1
semaphore-depth-10	0.019 s	0.019 s	1
sha512-100-bytes	0.099 s	0.1 s	0.99

This comment was automatically generated by workflow using github-action-benchmark.

[github-actions]

⚠️ Performance Alert ⚠️

Possible performance regression was detected for benchmark 'Execution Time'.
Benchmark result of this commit is worse than the previous benchmark result exceeding threshold 1.20.

Benchmark suite	Current: 38979ee	Previous: cc0c20d	Ratio
private-kernel-inner	0.019 s	0.014 s	1.36

This comment was automatically generated by workflow using github-action-benchmark.

CC: @TomAFrench

[github-actions]

Compilation Time

Benchmark suite	Current: ad2a326	Previous: b544e60	Ratio
private-kernel-inner	1.78 s	1.75 s	1.02
private-kernel-reset	7.796 s	7.686 s	1.01
private-kernel-tail	1.33 s	1.426 s	0.93
rollup-base-private	15.26 s	15.36 s	0.99
rollup-base-public	14.3 s	14.16 s	1.01
rollup-block-root-empty	22.98 s	21.32 s	1.08
rollup-block-root-single-tx	203 s	199 s	1.02
rollup-block-root	200 s	210 s	0.95
rollup-merge	1.308 s	1.358 s	0.96
rollup-root	1.46 s	1.47 s	0.99
semaphore-depth-10	0.787 s	0.777 s	1.01
sha512-100-bytes	1.539 s	1.624 s	0.95

This comment was automatically generated by workflow using github-action-benchmark.

[github-actions]

Opcode count

Benchmark suite	Current: ad2a326	Previous: b544e60	Ratio
private-kernel-inner	14792 opcodes	14792 opcodes	1
private-kernel-reset	68868 opcodes	68868 opcodes	1
private-kernel-tail	11177 opcodes	11177 opcodes	1
rollup-base-private	221335 opcodes	221335 opcodes	1
rollup-base-public	159954 opcodes	159954 opcodes	1
rollup-block-root-empty	68106 opcodes	68106 opcodes	1
rollup-block-root-single-tx	964509 opcodes	964509 opcodes	1
rollup-block-root	965795 opcodes	965795 opcodes	1
rollup-merge	1409 opcodes	1409 opcodes	1
rollup-root	2631 opcodes	2631 opcodes	1
semaphore-depth-10	5700 opcodes	5700 opcodes	1
sha512-100-bytes	13173 opcodes	13173 opcodes	1

This comment was automatically generated by workflow using github-action-benchmark.

[github-actions]

Artifact Size

Benchmark suite	Current: ad2a326	Previous: b544e60	Ratio
private-kernel-inner	708.9 KB	708.9 KB	1
private-kernel-reset	2032.7 KB	2032.7 KB	1
private-kernel-tail	536.4 KB	536.5 KB	1.00
rollup-base-private	4319.4 KB	4320.9 KB	1.00
rollup-base-public	3334.1 KB	3334.3 KB	1.00
rollup-block-root-empty	3856.2 KB	3857 KB	1.00
rollup-block-root-single-tx	30756.1 KB	30756.4 KB	1.00
rollup-block-root	30785.7 KB	30786.1 KB	1.00
rollup-merge	188.2 KB	188.2 KB	1
rollup-root	390.4 KB	390.5 KB	1.00
semaphore-depth-10	631.5 KB	631.5 KB	1
sha512-100-bytes	525.5 KB	525.5 KB	1

This comment was automatically generated by workflow using github-action-benchmark.

[github-actions]

Execution Memory

Benchmark suite	Current: ad2a326	Previous: b544e60	Ratio
private-kernel-inner	212.98 MB	212.98 MB	1
private-kernel-reset	246.18 MB	246.18 MB	1
private-kernel-tail	197.81 MB	197.81 MB	1
rollup-base-private	501.57 MB	501.57 MB	1
rollup-base-public	434.03 MB	434.03 MB	1
rollup-block-root	1500 MB	1500 MB	1
rollup-merge	328.36 MB	328.36 MB	1
rollup-root	330.89 MB	330.89 MB	1
semaphore_depth_10	69.53 MB	69.53 MB	1
sha512_100_bytes	55.03 MB	55.03 MB	1

This comment was automatically generated by workflow using github-action-benchmark.

[github-actions]

Compilation Memory

Benchmark suite	Current: ad2a326	Previous: b544e60	Ratio
private-kernel-inner	239.62 MB	239.58 MB	1.00
private-kernel-reset	549.15 MB	549.15 MB	1
private-kernel-tail	214.04 MB	213.94 MB	1.00
rollup-base-private	1350 MB	1350 MB	1
rollup-base-public	1400 MB	1400 MB	1
rollup-block-root-empty	1010 MB	1010 MB	1
rollup-block-root-single-tx	9690 MB	9690 MB	1
rollup-block-root	9690 MB	9690 MB	1
rollup-merge	330.61 MB	330.59 MB	1.00
rollup-root	341.38 MB	341.33 MB	1.00
semaphore_depth_10	104.75 MB	104.73 MB	1.00
sha512_100_bytes	233.01 MB	232.98 MB	1.00

This comment was automatically generated by workflow using github-action-benchmark.

[github-actions]

Test Suite Duration

Benchmark suite	Current: ad2a326	Previous: b544e60	Ratio
test_report_AztecProtocol_aztec-packages_noir-projects_aztec-nr	97 s	99 s	0.98
test_report_AztecProtocol_aztec-packages_noir-projects_noir-contracts	111 s	109 s	1.02
test_report_AztecProtocol_aztec-packages_noir-projects_noir-protocol-circuits_crates_blob	160 s	188 s	0.85
test_report_AztecProtocol_aztec-packages_noir-projects_noir-protocol-circuits_crates_private-kernel-lib	209 s	208 s	1.00
test_report_AztecProtocol_aztec-packages_noir-projects_noir-protocol-circuits_crates_reset-kernel-lib	34 s	33 s	1.03
test_report_AztecProtocol_aztec-packages_noir-projects_noir-protocol-circuits_crates_rollup-lib	629 s	593 s	1.06
test_report_AztecProtocol_aztec-packages_noir-projects_noir-protocol-circuits_crates_types	95 s	93 s	1.02
test_report_noir-lang_noir-bignum_	134 s	136 s	0.99
test_report_noir-lang_noir_bigcurve_	347 s	279 s	1.24
test_report_noir-lang_sha256_	15 s	15 s	1
test_report_noir-lang_sha512_	12 s	15 s	0.80
test_report_zkpassport_noir-ecdsa_	1 s	2 s	0.50
test_report_zkpassport_noir_rsa_	2 s	2 s	1

This comment was automatically generated by workflow using github-action-benchmark.

[asterite]

Looks great!