feat: avm ts simulator accumulates debuglogs into ProcessedTx

dbanks12 · dbanks12 · commit 38595f797d5b · 2025-08-30T18:36:51.000Z
diff --git a/yarn-project/simulator/src/public/avm/opcodes/misc.test.ts b/yarn-project/simulator/src/public/avm/opcodes/misc.test.ts
@@ -1,7 +1,9 @@
 import { jest } from '@jest/globals';
+import { mock } from 'jest-mock-extended';
 
+import type { PublicSideEffectTraceInterface } from '../../side_effect_trace_interface.js';
 import { Field, Uint8, Uint32 } from '../avm_memory_types.js';
-import { initContext, initExecutionEnvironment } from '../fixtures/initializers.js';
+import { initContext, initExecutionEnvironment, initPersistableStateManager } from '../fixtures/initializers.js';
 import { Opcode } from '../serialization/instruction_serialization.js';
 import { DebugLog } from './misc.js';
 
@@ -30,7 +32,9 @@ describe('Misc Instructions', () => {
 
     it('Should execute DebugLog in client-initiated simulation mode', async () => {
       const env = initExecutionEnvironment({ clientInitiatedSimulation: true });
-      const context = initContext({ env });
+      const trace = mock<PublicSideEffectTraceInterface>();
+      const persistableState = initPersistableStateManager({ trace });
+      const context = initContext({ env, persistableState });
       // Set up memory with message and fields
       const messageOffset = 10;
       const fieldsOffset = 100;
@@ -64,6 +68,10 @@ describe('Misc Instructions', () => {
 
         // Check that logger.verbose was called with formatted message
         expect(mockVerbose).toHaveBeenCalledWith(`Hello ${fieldValue.toFr()}!`);
+
+        // expect debug log to be traced
+        const msgId = 0; // TODO(dbanks12): implement messageId
+        expect(trace.traceDebugLog).toHaveBeenCalledWith(msgId, [fieldValue.toFr()]);
       } finally {
         // Restore the mock
         mockIsVerbose.mockRestore();
diff --git a/yarn-project/simulator/src/public/avm/opcodes/misc.ts b/yarn-project/simulator/src/public/avm/opcodes/misc.ts
@@ -55,14 +55,19 @@ export class DebugLog extends Instruction {
       memory.checkTagsRange(TypeTag.UINT8, messageOffset, this.messageSize);
       memory.checkTagsRange(TypeTag.FIELD, fieldsOffset, fieldsSize);
 
-      // Interpret str<N> = [u8; N] to string.
-      const messageAsStr = rawMessage.map(field => String.fromCharCode(field.toNumber())).join('');
-      const formattedStr = applyStringFormatting(
-        messageAsStr,
-        fields.map(field => field.toFr()),
-      );
+      // Convert fields to Fr array for the side effect trace
+      const fieldsAsFr = fields.map(field => field.toFr());
 
-      DebugLog.logger.verbose(formattedStr);
+      const messageId = 0; // TODO(dbanks12): implement messageId as operand
+      context.persistableState.writeDebugLog(messageId, fieldsAsFr);
+
+      if (DebugLog.logger.isLevelEnabled('verbose')) {
+        // Interpret str<N> = [u8; N] to string.
+        const messageAsStr = rawMessage.map(field => String.fromCharCode(field.toNumber())).join('');
+        const formattedStr = applyStringFormatting(messageAsStr, fieldsAsFr);
+
+        DebugLog.logger.verbose(formattedStr);
+      }
     }
   }
 }
diff --git a/yarn-project/simulator/src/public/public_processor/public_processor.ts b/yarn-project/simulator/src/public/public_processor/public_processor.ts
@@ -513,7 +513,7 @@ export class PublicProcessor implements Traceable {
   private async processTxWithPublicCalls(tx: Tx): Promise<[ProcessedTx, NestedProcessReturnValues[]]> {
     const timer = new Timer();
 
-    const { avmProvingRequest, gasUsed, revertCode, revertReason, processedPhases } =
+    const { avmProvingRequest, gasUsed, revertCode, revertReason, processedPhases, publicDebuggedLogs } =
       await this.publicTxSimulator.simulate(tx);
 
     if (!avmProvingRequest) {
@@ -542,7 +542,14 @@ export class PublicProcessor implements Traceable {
     const durationMs = timer.ms();
     this.metrics.recordTx(phaseCount, durationMs, gasUsed.publicGas);
 
-    const processedTx = makeProcessedTxFromTxWithPublicCalls(tx, avmProvingRequest, gasUsed, revertCode, revertReason);
+    const processedTx = makeProcessedTxFromTxWithPublicCalls(
+      tx,
+      avmProvingRequest,
+      gasUsed,
+      revertCode,
+      revertReason,
+      publicDebuggedLogs,
+    );
 
     const returnValues = processedPhases.find(({ phase }) => phase === TxExecutionPhase.APP_LOGIC)?.returnValues ?? [];
 
diff --git a/yarn-project/simulator/src/public/public_tx_simulator/public_tx_context.ts b/yarn-project/simulator/src/public/public_tx_simulator/public_tx_context.ts
@@ -289,6 +289,13 @@ export class PublicTxContext {
     return txFee;
   }
 
+  /**
+   * Get the public debugged logs accumulated during this transaction.
+   */
+  public getDebugLogs() {
+    return this.trace.getSideEffects().publicDebuggedLogs;
+  }
+
   /**
    * Generate the public inputs for the AVM circuit.
    */
diff --git a/yarn-project/simulator/src/public/public_tx_simulator/public_tx_simulator.ts b/yarn-project/simulator/src/public/public_tx_simulator/public_tx_simulator.ts
@@ -13,6 +13,7 @@ import {
 } from '@aztec/stdlib/avm';
 import { SimulationError } from '@aztec/stdlib/errors';
 import type { Gas, GasUsed } from '@aztec/stdlib/gas';
+import type { PublicDebuggedLog } from '@aztec/stdlib/logs';
 import { ProvingRequestType } from '@aztec/stdlib/proofs';
 import type { MerkleTreeWriteOperations } from '@aztec/stdlib/trees';
 import {
@@ -47,6 +48,8 @@ export type PublicTxResult = {
   /** Revert reason, if any */
   revertReason?: SimulationError;
   processedPhases: ProcessedPhase[];
+  /** Debug logs emitted during public execution */
+  publicDebuggedLogs: PublicDebuggedLog[];
 };
 
 export class PublicTxSimulator {
@@ -176,6 +179,7 @@ export class PublicTxSimulator {
         revertCode,
         revertReason: context.revertReason,
         processedPhases: processedPhases,
+        publicDebuggedLogs: context.getDebugLogs(),
       };
     } finally {
       // Make sure there are no new contracts in the tx-level cache.
diff --git a/yarn-project/simulator/src/public/side_effect_trace.test.ts b/yarn-project/simulator/src/public/side_effect_trace.test.ts
@@ -15,7 +15,7 @@ import { PublicDataUpdateRequest } from '@aztec/stdlib/avm';
 import { AztecAddress } from '@aztec/stdlib/aztec-address';
 import { computePublicDataTreeLeafSlot } from '@aztec/stdlib/hash';
 import { NoteHash, Nullifier } from '@aztec/stdlib/kernel';
-import { PublicLog } from '@aztec/stdlib/logs';
+import { PublicDebuggedLog, PublicLog } from '@aztec/stdlib/logs';
 import { L2ToL1Message } from '@aztec/stdlib/messaging';
 import { makeContractClassPublic } from '@aztec/stdlib/testing';
 
@@ -31,6 +31,8 @@ describe('Public Side Effect Trace', () => {
   const recipient = Fr.random();
   const content = Fr.random();
   const log = [Fr.random(), Fr.random(), Fr.random()];
+  const debugLogMessageId = 42;
+  const debugLog = [new Fr(1), new Fr(2)];
 
   let startCounter: number;
   let startCounterPlus1: number;
@@ -88,6 +90,11 @@ describe('Public Side Effect Trace', () => {
     expect(trace.getSideEffects().publicLogs).toEqual([expectedLog]);
   });
 
+  it('Should trace debug logs', () => {
+    trace.traceDebugLog(debugLogMessageId, debugLog);
+    expect(trace.getSideEffects().publicDebuggedLogs).toEqual([new PublicDebuggedLog(debugLogMessageId, debugLog)]);
+  });
+
   describe('Maximum accesses', () => {
     it('Should enforce maximum number of user public storage writes', async () => {
       for (let i = 0; i < MAX_PUBLIC_DATA_UPDATE_REQUESTS_PER_TX; i++) {
@@ -228,6 +235,7 @@ describe('Public Side Effect Trace', () => {
       testCounter++;
       nestedTrace.tracePublicLog(address, log);
       testCounter++;
+      nestedTrace.traceDebugLog(debugLogMessageId, debugLog); // no counter incr
 
       trace.merge(nestedTrace, reverted);
 
@@ -244,6 +252,8 @@ describe('Public Side Effect Trace', () => {
         expect(parentSideEffects.nullifiers).toEqual([]);
         expect(parentSideEffects.l2ToL1Msgs).toEqual([]);
         expect(parentSideEffects.publicLogs).toEqual([]);
+        // debug logs don't get dropped on revert
+        expect(parentSideEffects.publicDebuggedLogs).toEqual([new PublicDebuggedLog(debugLogMessageId, debugLog)]);
         // parent trace does not adopt nested call's writtenPublicDataSlots
         expect(trace.isStorageCold(address, slot)).toBe(true);
       } else {
diff --git a/yarn-project/simulator/src/public/side_effect_trace.ts b/yarn-project/simulator/src/public/side_effect_trace.ts
@@ -16,7 +16,7 @@ import { PublicDataUpdateRequest } from '@aztec/stdlib/avm';
 import type { AztecAddress } from '@aztec/stdlib/aztec-address';
 import { computePublicDataTreeLeafSlot } from '@aztec/stdlib/hash';
 import { NoteHash, Nullifier } from '@aztec/stdlib/kernel';
-import { PublicLog } from '@aztec/stdlib/logs';
+import { PublicDebuggedLog, PublicLog } from '@aztec/stdlib/logs';
 import { L2ToL1Message, ScopedL2ToL1Message } from '@aztec/stdlib/messaging';
 
 import { strict as assert } from 'assert';
@@ -36,6 +36,7 @@ export type SideEffects = {
   nullifiers: Nullifier[];
   l2ToL1Msgs: ScopedL2ToL1Message[];
   publicLogs: PublicLog[];
+  publicDebuggedLogs: PublicDebuggedLog[];
 };
 
 export class SideEffectArrayLengths {
@@ -69,6 +70,7 @@ export class SideEffectTrace implements PublicSideEffectTraceInterface {
   private nullifiers: Nullifier[] = [];
   private l2ToL1Messages: ScopedL2ToL1Message[] = [];
   private publicLogs: PublicLog[] = [];
+  private publicDebuggedLogs: PublicDebuggedLog[] = [];
 
   /** Make sure a forked trace is never merged twice. */
   private alreadyMergedIntoParent = false;
@@ -114,6 +116,9 @@ export class SideEffectTrace implements PublicSideEffectTraceInterface {
     this.sideEffectCounter = forkedTrace.sideEffectCounter;
     this.uniqueClassIds.acceptAndMerge(forkedTrace.uniqueClassIds);
 
+    // Debug logs are always merged, even on revert
+    this.publicDebuggedLogs.push(...forkedTrace.publicDebuggedLogs);
+
     if (!reverted) {
       this.publicDataWrites.push(...forkedTrace.publicDataWrites);
       this.noteHashes.push(...forkedTrace.noteHashes);
@@ -237,6 +242,12 @@ export class SideEffectTrace implements PublicSideEffectTraceInterface {
     this.incrementSideEffectCounter();
   }
 
+  public traceDebugLog(messageId: number, fields: Fr[]) {
+    // Debug logs don't have a limit like other side effects
+    const debugLog = new PublicDebuggedLog(messageId, fields);
+    this.publicDebuggedLogs.push(debugLog);
+  }
+
   public traceGetContractClass(contractClassId: Fr, exists: boolean) {
     // We limit the number of unique contract class IDs due to hashing and the trace length limit.
     if (exists && !this.uniqueClassIds.has(contractClassId.toString())) {
@@ -260,6 +271,7 @@ export class SideEffectTrace implements PublicSideEffectTraceInterface {
       nullifiers: this.nullifiers,
       l2ToL1Msgs: this.l2ToL1Messages,
       publicLogs: this.publicLogs,
+      publicDebuggedLogs: this.publicDebuggedLogs,
     };
   }
 }
diff --git a/yarn-project/simulator/src/public/side_effect_trace_interface.ts b/yarn-project/simulator/src/public/side_effect_trace_interface.ts
@@ -18,5 +18,6 @@ export interface PublicSideEffectTraceInterface {
   traceNewNullifier(siloedNullifier: Fr): void;
   traceNewL2ToL1Message(contractAddress: AztecAddress, recipient: Fr, content: Fr): void;
   tracePublicLog(contractAddress: AztecAddress, log: Fr[]): void;
+  traceDebugLog(messageId: number, fields: Fr[]): void;
   traceGetContractClass(contractClassId: Fr, exists: boolean): void;
 }
diff --git a/yarn-project/simulator/src/public/state_manager/state_manager.ts b/yarn-project/simulator/src/public/state_manager/state_manager.ts
@@ -329,6 +329,15 @@ export class PublicPersistableStateManager {
     this.trace.tracePublicLog(contractAddress, log);
   }
 
+  /**
+   * Write a debug log
+   * @param messageId - message ID (currently always 0)
+   * @param fields - debug log fields
+   */
+  public writeDebugLog(messageId: number, fields: Fr[]) {
+    this.trace.traceDebugLog(messageId, fields);
+  }
+
   /**
    * Get a contract instance.
    * @param contractAddress - address of the contract instance to retrieve.
diff --git a/yarn-project/stdlib/src/logs/index.ts b/yarn-project/stdlib/src/logs/index.ts
@@ -2,6 +2,7 @@ export * from './log_with_tx_data.js';
 export * from './indexed_tagging_secret.js';
 export * from './contract_class_log.js';
 export * from './public_log.js';
+export * from './public_debugged_log.js';
 export * from './private_log.js';
 export * from './pending_tagged_log.js';
 export * from './log_id.js';
diff --git a/yarn-project/stdlib/src/logs/public_debugged_log.ts b/yarn-project/stdlib/src/logs/public_debugged_log.ts
@@ -0,0 +1,55 @@
+import type { FieldsOf } from '@aztec/foundation/array';
+import { Fr } from '@aztec/foundation/fields';
+import { BufferReader, FieldReader, serializeToBuffer, serializeToFields } from '@aztec/foundation/serialize';
+
+/**
+ * Represents a debug log emitted during public execution.
+ */
+export class PublicDebuggedLog {
+  constructor(
+    /** Message ID (currently always 0, reserved for future use) */
+    public messageId: number,
+    /** The fields array from the DebugLog opcode */
+    public fields: Fr[],
+  ) {}
+
+  static from(fields: FieldsOf<PublicDebuggedLog>) {
+    return new PublicDebuggedLog(fields.messageId, fields.fields);
+  }
+
+  toBuffer(): Buffer {
+    return serializeToBuffer([this.messageId, this.fields.length, this.fields]);
+  }
+
+  static fromBuffer(buffer: Buffer | BufferReader): PublicDebuggedLog {
+    const reader = BufferReader.asReader(buffer);
+    const messageId = reader.readNumber();
+    const fieldsLength = reader.readNumber();
+    const fields = reader.readArray(fieldsLength, Fr);
+    return new PublicDebuggedLog(messageId, fields);
+  }
+
+  toFields(): Fr[] {
+    return serializeToFields([this.messageId, this.fields.length, this.fields]);
+  }
+
+  static fromFields(fields: Fr[] | FieldReader): PublicDebuggedLog {
+    const reader = FieldReader.asReader(fields);
+    const messageId = reader.readField().toNumber();
+    const fieldsLength = reader.readField().toNumber();
+    const fieldsArray = reader.readFieldArray(fieldsLength);
+    return new PublicDebuggedLog(messageId, fieldsArray);
+  }
+
+  toString(): string {
+    return `PublicDebuggedLog { messageId: ${this.messageId}, fields: [${this.fields.map(f => f.toString()).join(', ')}] }`;
+  }
+
+  equals(other: PublicDebuggedLog): boolean {
+    return (
+      this.messageId === other.messageId &&
+      this.fields.length === other.fields.length &&
+      this.fields.every((field, index) => field.equals(other.fields[index]))
+    );
+  }
+}
diff --git a/yarn-project/stdlib/src/tests/factories.ts b/yarn-project/stdlib/src/tests/factories.ts
@@ -1732,7 +1732,8 @@ export async function makeBloatedProcessedTx({
       },
       gasUsed,
       RevertCode.OK,
-      undefined /* revertReason */,
+      /*revertReason=*/ undefined,
+      /*publicDebuggedLogs=*/ [],
     );
   }
 }
diff --git a/yarn-project/stdlib/src/tx/processed_tx.ts b/yarn-project/stdlib/src/tx/processed_tx.ts
@@ -8,6 +8,7 @@ import { Gas } from '../gas/gas.js';
 import type { GasUsed } from '../gas/gas_used.js';
 import { computeL2ToL1MessageHash } from '../hash/hash.js';
 import type { PrivateKernelTailCircuitPublicInputs } from '../kernel/private_kernel_tail_circuit_public_inputs.js';
+import type { PublicDebuggedLog } from '../logs/public_debugged_log.js';
 import type { ClientIvcProof } from '../proofs/client_ivc_proof.js';
 import type { GlobalVariables } from './global_variables.js';
 import type { Tx } from './tx.js';
@@ -61,6 +62,10 @@ export type ProcessedTx = {
    * Reason the tx was reverted.
    */
   revertReason: SimulationError | undefined;
+  /**
+   * Debug logs emitted during public execution.
+   */
+  publicDebuggedLogs: PublicDebuggedLog[];
 };
 
 /**
@@ -125,6 +130,7 @@ export function makeProcessedTxFromPrivateOnlyTx(
     gasUsed,
     revertCode: RevertCode.OK,
     revertReason: undefined,
+    publicDebuggedLogs: [],
   };
 }
 
@@ -140,6 +146,7 @@ export function makeProcessedTxFromTxWithPublicCalls(
   gasUsed: GasUsed,
   revertCode: RevertCode,
   revertReason: SimulationError | undefined,
+  publicDebuggedLogs: PublicDebuggedLog[] = [],
 ): ProcessedTx {
   const avmPublicInputs = avmProvingRequest.inputs.publicInputs;
 
@@ -189,5 +196,6 @@ export function makeProcessedTxFromTxWithPublicCalls(
     gasUsed,
     revertCode,
     revertReason,
+    publicDebuggedLogs,
   };
 }

Original file line number	Diff line number	Diff line change
`@@ -18,5 +18,6 @@ export interface PublicSideEffectTraceInterface {`
`18`	`18`	`traceNewNullifier(siloedNullifier: Fr): void;`
`19`	`19`	`traceNewL2ToL1Message(contractAddress: AztecAddress, recipient: Fr, content: Fr): void;`
`20`	`20`	`tracePublicLog(contractAddress: AztecAddress, log: Fr[]): void;`
	`21`	`+ traceDebugLog(messageId: number, fields: Fr[]): void;`
`21`	`22`	`traceGetContractClass(contractClassId: Fr, exists: boolean): void;`
`22`	`23`	`}`