fix extCodeCopy mmuCall when empty account (and thus no cfi)

Signed-off-by: F Bojarski <[email protected]>

arithmetization/src/main/java/net/consensys/linea/zktracer/module/hub/fragment/imc/mmu/opcode/ExtCodeCopy.java

@@ -24,6 +24,7 @@
 import net.consensys.linea.zktracer.module.hub.fragment.imc.mmu.MmuCall;
 import net.consensys.linea.zktracer.module.romlex.ContractMetadata;
 import net.consensys.linea.zktracer.types.EWord;
+import org.apache.tuweni.bytes.Bytes;
 import org.hyperledger.besu.datatypes.Address;
 import org.hyperledger.besu.evm.internal.Words;
 import org.hyperledger.besu.evm.worldstate.WorldView;
@@ -44,8 +45,7 @@ public ExtCodeCopy(final Hub hub) {
  final Address foreignCodeAddress = Words.toAddress(hub.messageFrame().getStackItem(0));
  this.contract = ContractMetadata.canonical(hub, foreignCodeAddress);
 
- this.exoBytes(Optional.of(hub.romLex().getCodeByMetadata(contract)))
- .targetId(hub.currentFrame().contextNumber())
+ this.targetId(hub.currentFrame().contextNumber())
  .targetRamBytes(
  Optional.of(
  hub.currentFrame()
@@ -57,12 +57,24 @@ public ExtCodeCopy(final Hub hub) {
  .setRom();
  }
 
+ @Override
+ public Optional<Bytes> exoBytes() {
+ try {
+ return Optional.of(hub.romLex().getCodeByMetadata(contract));
+ } catch (Exception ignored) {
+ // Can be empty Bytes in case the ext account is empty. In this case, no associated CFI
+ return Optional.of(Bytes.EMPTY);
+ }
+ }
+
  @Override
  public long referenceSize() {
- return hub.romLex()
- .getChunkByMetadata(contract)
- .map(chunk -> chunk.byteCode().size())
- .orElse(0);
+ try {
+ return (hub.romLex().getCodeByMetadata(contract).size());
+ } catch (Exception ignored) {
+ // Can be 0 in case the ext account is empty. In this case, no associated CFI
+ return 0;
+ }
  }
 
  @Override