feat: Emit single functions from class registerer

[spalladino]

Adds functions to broadcast individual private and unconstrained functions from the class registerer contract. This is not required for a contract to be callable, but it's rather a convenience for easily broadcasting private and unconstrained functions to all users.

The node does not yet capture these events.

Fixes #4427

[AztecBot]

Benchmark results

Metrics with a significant change:

• note_trial_decrypting_time_in_ms (32): 109 (+148%)

Detailed results

All benchmarks are run on txs on the Benchmarking contract on the repository. Each tx consists of a batch call to create_note and increment_balance, which guarantees that each tx has a private call, a nested private call, a public call, and a nested public call, as well as an emitted private note, an unencrypted log, and public storage read and write.

This benchmark source data is available in JSON format on S3 here.

Values are compared against data from master at commit 4de25403 and shown if the difference exceeds 1%.

L2 block published to L1

Each column represents the number of txs on an L2 block published to L1.

Metric	8 txs	32 txs	128 txs
l1_rollup_calldata_size_in_bytes	45,636	180,516	720,036
l1_rollup_calldata_gas	222,600	870,636	3,463,992
l1_rollup_execution_gas	315,087	988,376	3,683,649
l2_block_processing_time_in_ms	1,197 (+3%)	4,348 (-4%)	17,226
note_successful_decrypting_time_in_ms	302 (-1%)	981 (-2%)	3,587
note_trial_decrypting_time_in_ms	11.4 (-18%)	⚠️ 109 (+148%)	139 (-5%)
l2_block_building_time_in_ms	17,851	70,688	284,127
l2_block_rollup_simulation_time_in_ms	13,037	51,581	207,932
l2_block_public_tx_process_time_in_ms	4,787	19,027	75,927 (-1%)

L2 chain processing

Each column represents the number of blocks on the L2 chain where each block has 16 txs.

Metric	5 blocks	10 blocks
node_history_sync_time_in_ms	14,146 (+2%)	27,463 (+4%)
note_history_successful_decrypting_time_in_ms	2,491	4,655 (+1%)
note_history_trial_decrypting_time_in_ms	99.7 (+8%)	248 (+7%)
node_database_size_in_bytes	17,363,024	33,071,184
pxe_database_size_in_bytes	29,923	59,478

Circuits stats

Stats on running time and I/O sizes collected for every circuit run across all benchmarks.

Circuit	circuit_simulation_time_in_ms	circuit_input_size_in_bytes	circuit_output_size_in_bytes
private-kernel-init	310	44,512	26,225
private-kernel-ordering	198	44,545	16,625
base-rollup	1,407	129,002	881
root-rollup	82.6	4,088	677
private-kernel-inner	445	71,703	26,225
public-kernel-private-input	247	32,647	26,225
public-kernel-non-first-iteration	246	32,689	26,225
merge-rollup	7.65 (+1%)	2,608	881

Tree insertion stats

The duration to insert a fixed batch of leaves into each tree type.

Metric	1 leaves	2 leaves	8 leaves	16 leaves	32 leaves	128 leaves	64 leaves	512 leaves	1024 leaves	2048 leaves	8192 leaves
batch_insert_into_append_only_tree_16_depth_ms	10.2	11.2 (+5%)	12.7	16.9 (-1%)	22.9 (+1%)	64.5 (+1%)	N/A	N/A	N/A	N/A	N/A
batch_insert_into_append_only_tree_16_depth_hash_count	16.9	17.5	23.0	31.6	47.0	143	N/A	N/A	N/A	N/A	N/A
batch_insert_into_append_only_tree_16_depth_hash_ms	0.594	0.622 (+5%)	0.540	0.524 (-1%)	0.479 (+1%)	0.444 (+1%)	N/A	N/A	N/A	N/A	N/A
batch_insert_into_append_only_tree_32_depth_ms	N/A	N/A	N/A	N/A	N/A	74.7 (-1%)	47.6	239	462	901 (-7%)	3,569
batch_insert_into_append_only_tree_32_depth_hash_count	N/A	N/A	N/A	N/A	N/A	159	96.0	543	1,055	2,079	8,223
batch_insert_into_append_only_tree_32_depth_hash_ms	N/A	N/A	N/A	N/A	N/A	0.461 (-1%)	0.488	0.437	0.432	0.428 (-7%)	0.428
batch_insert_into_indexed_tree_20_depth_ms	N/A	N/A	N/A	N/A	N/A	104	56.7	354 (+2%)	689	1,358 (-4%)	5,422
batch_insert_into_indexed_tree_20_depth_hash_count	N/A	N/A	N/A	N/A	N/A	197	104	691	1,363	2,707	10,771
batch_insert_into_indexed_tree_20_depth_hash_ms	N/A	N/A	N/A	N/A	N/A	0.493 (-1%)	0.497	0.482 (+2%)	0.473	0.470 (-5%)	0.472
batch_insert_into_indexed_tree_40_depth_ms	N/A	N/A	N/A	56.6	N/A	N/A	N/A	N/A	N/A	N/A	N/A
batch_insert_into_indexed_tree_40_depth_hash_count	N/A	N/A	N/A	94.1	N/A	N/A	N/A	N/A	N/A	N/A	N/A
batch_insert_into_indexed_tree_40_depth_hash_ms	N/A	N/A	N/A	0.579	N/A	N/A	N/A	N/A	N/A	N/A	N/A

Miscellaneous

Transaction sizes based on how many contracts are deployed in the tx.

Metric	0 deployed contracts	1 deployed contracts
tx_size_in_bytes	17,271	40,063

Transaction processing duration by data writes.

Metric	0 new commitments	1 new commitments
tx_pxe_processing_time_ms	556 (-1%)	1,318

Metric	0 public data writes	1 public data writes
tx_sequencer_processing_time_ms	0.537 (-4%)	591

[just-mitch]

I asked chatgpt if there was a cleaner way to do this, and FWIW:

const artifactHash = 'artifactHash' in artifact
    ? artifact.artifactHash
    : computeArtifactHash(artifact);

[spalladino]

Nice, thanks! I'll switch to this style.

[just-mitch]

Should this be Buffer.alloc(Fr.SIZE_IN_BYTES) ? Also, do we only write 31 byte chunks to ensure we don't overflow the size of a field element?

[spalladino]

Should this be Buffer.alloc(Fr.SIZE_IN_BYTES) ?

Yep, you're right, I'll change in an upcoming PR.

Also, do we only write 31 byte chunks to ensure we don't overflow the size of a field element?

That's correct. A field element fits between 31 and 32 bytes.

[just-mitch]

Can you explain why we need both sibling paths here? Their derivations above look very similar.

[spalladino]

That's an annoying bit. Private function information is split across two trees:

• The "private function tree" captures the selectors and verification keys, and is used in the kernel circuit for verifying the proof generated by the app circuit.
• The "artifact tree" captures function bytecode and metadata, and is used by the pxe to check that its executing the code it's supposed to be executing, but it never goes into circuits.

So we need two sibling paths, one for each piece of data. I've tried capturing it in the yellow paper here.