feat(avm-simulator): implement AVM message opcodes (simulator/transpi…

…ler/noir-test) (#4852)

Closes #4837 
Closes #4835 

Updated spec for both opcodes according to latest plan (and to more closely match existing Noir interface for private).

Misc cleanup.

[Latest discussion on `L1TOL2MSGEXISTS` opcode](https://aztecprotocol.slack.com/archives/C03P17YHVK8/p1709072769364739)

avm-transpiler/src/opcodes.rs

@@ -66,7 +66,7 @@ pub enum AvmOpcode {
     EMITNOTEHASH,    // Notes & Nullifiers
     NULLIFIEREXISTS, // Notes & Nullifiers
     EMITNULLIFIER,   // Notes & Nullifiers
-    READL1TOL2MSG,   // Messages
+    L1TOL2MSGEXISTS, // Messages
     HEADERMEMBER,    // Archive tree & Headers
 
     // Accrued Substate
@@ -154,7 +154,7 @@ impl AvmOpcode {
             AvmOpcode::EMITNOTEHASH => "EMITNOTEHASH", // Notes & Nullifiers
             AvmOpcode::NULLIFIEREXISTS => "NULLIFIEREXISTS", // Notes & Nullifiers
             AvmOpcode::EMITNULLIFIER => "EMITNULLIFIER", // Notes & Nullifiers
-            AvmOpcode::READL1TOL2MSG => "READL1TOL2MSG", // Messages
+            AvmOpcode::L1TOL2MSGEXISTS => "L1TOL2MSGEXISTS", // Messages
             AvmOpcode::HEADERMEMBER => "HEADERMEMBER", // Archive tree & Headers
 
             // Accrued Substate

avm-transpiler/src/transpile.rs

@@ -246,6 +246,8 @@ fn handle_foreign_call(
             inputs,
         ),
         "nullifierExists" => handle_nullifier_exists(avm_instrs, destinations, inputs),
+        "l1ToL2MsgExists" => handle_l1_to_l2_msg_exists(avm_instrs, destinations, inputs),
+        "sendL2ToL1Msg" => handle_send_l2_to_l1_msg(avm_instrs, destinations, inputs),
         "keccak256" | "sha256" => {
             handle_2_field_hash_instruction(avm_instrs, function, destinations, inputs)
         }
@@ -382,6 +384,99 @@ fn handle_nullifier_exists(
     });
 }
 
+/// Handle an AVM L1TOL2MSGEXISTS instruction
+/// (a l1ToL2MsgExists brillig foreign call was encountered)
+/// Adds the new instruction to the avm instructions list.
+fn handle_l1_to_l2_msg_exists(
+    avm_instrs: &mut Vec<AvmInstruction>,
+    destinations: &Vec<ValueOrArray>,
+    inputs: &Vec<ValueOrArray>,
+) {
+    if destinations.len() != 1 || inputs.len() != 2 {
+        panic!(
+            "Transpiler expects ForeignCall::L1TOL2MSGEXISTS to have 1 destinations and 2 input, got {} and {}",
+            destinations.len(),
+            inputs.len()
+        );
+    }
+    let msg_hash_offset_operand = match &inputs[0] {
+        ValueOrArray::MemoryAddress(offset) => offset.to_usize() as u32,
+        _ => panic!(
+            "Transpiler does not know how to handle ForeignCall::L1TOL2MSGEXISTS with HeapArray/Vector inputs",
+        ),
+    };
+    let msg_leaf_index_offset_operand = match &inputs[1] {
+        ValueOrArray::MemoryAddress(offset) => offset.to_usize() as u32,
+        _ => panic!(
+            "Transpiler does not know how to handle ForeignCall::L1TOL2MSGEXISTS with HeapArray/Vector inputs",
+        ),
+    };
+    let exists_offset_operand = match &destinations[0] {
+        ValueOrArray::MemoryAddress(offset) => offset.to_usize() as u32,
+        _ => panic!(
+            "Transpiler does not know how to handle ForeignCall::L1TOL2MSGEXISTS with HeapArray/Vector inputs",
+        ),
+    };
+    avm_instrs.push(AvmInstruction {
+        opcode: AvmOpcode::L1TOL2MSGEXISTS,
+        indirect: Some(ALL_DIRECT),
+        operands: vec![
+            AvmOperand::U32 {
+                value: msg_hash_offset_operand,
+            },
+            AvmOperand::U32 {
+                value: msg_leaf_index_offset_operand,
+            },
+            AvmOperand::U32 {
+                value: exists_offset_operand,
+            },
+        ],
+        ..Default::default()
+    });
+}
+
+/// Handle an AVM SENDL2TOL1MSG
+/// (a sendL2ToL1Msg brillig foreign call was encountered)
+/// Adds the new instruction to the avm instructions list.
+fn handle_send_l2_to_l1_msg(
+    avm_instrs: &mut Vec<AvmInstruction>,
+    destinations: &Vec<ValueOrArray>,
+    inputs: &Vec<ValueOrArray>,
+) {
+    if destinations.len() != 0 || inputs.len() != 2 {
+        panic!(
+            "Transpiler expects ForeignCall::SENDL2TOL1MSG to have 0 destinations and 2 inputs, got {} and {}",
+            destinations.len(),
+            inputs.len()
+        );
+    }
+    let recipient_offset_operand = match &inputs[0] {
+        ValueOrArray::MemoryAddress(offset) => offset.to_usize() as u32,
+        _ => panic!(
+            "Transpiler does not know how to handle ForeignCall::SENDL2TOL1MSG with HeapArray/Vector inputs",
+        ),
+    };
+    let content_offset_operand = match &inputs[1] {
+        ValueOrArray::MemoryAddress(offset) => offset.to_usize() as u32,
+        _ => panic!(
+            "Transpiler does not know how to handle ForeignCall::SENDL2TOL1MSG with HeapArray/Vector inputs",
+        ),
+    };
+    avm_instrs.push(AvmInstruction {
+        opcode: AvmOpcode::SENDL2TOL1MSG,
+        indirect: Some(ALL_DIRECT),
+        operands: vec![
+            AvmOperand::U32 {
+                value: recipient_offset_operand,
+            },
+            AvmOperand::U32 {
+                value: content_offset_operand,
+            },
+        ],
+        ..Default::default()
+    });
+}
+
 /// Two field hash instructions represent instruction's that's outputs are larger than a field element
 ///
 /// This includes:

barretenberg/cpp/src/barretenberg/vm/avm_trace/avm_opcode.cpp

@@ -72,7 +72,7 @@ const std::unordered_map<OpCode, size_t> Bytecode::OPERANDS_NUM = {
     //{ OpCode::EMITNOTEHASH, }, // Notes & Nullifiers
     //{ OpCode::NULLIFIEREXISTS, }, // Notes & Nullifiers
     //{ OpCode::EMITNULLIFIER, }, // Notes & Nullifiers
-    //{ OpCode::READL1TOL2MSG, }, // Messages
+    //{ OpCode::L1TOL2MSGEXISTS, }, // Messages
     //{ OpCode::HEADERMEMBER, },
 
     //// Accrued Substate
@@ -146,7 +146,7 @@ bool Bytecode::has_in_tag(OpCode const op_code)
     case OpCode::EMITNOTEHASH:
     case OpCode::NULLIFIEREXISTS:
     case OpCode::EMITNULLIFIER:
-    case OpCode::READL1TOL2MSG:
+    case OpCode::L1TOL2MSGEXISTS:
     case OpCode::HEADERMEMBER:
     case OpCode::EMITUNENCRYPTEDLOG:
     case OpCode::SENDL2TOL1MSG:

barretenberg/cpp/src/barretenberg/vm/avm_trace/avm_opcode.hpp

@@ -80,7 +80,7 @@ enum class OpCode : uint8_t {
     EMITNOTEHASH,    // Notes & Nullifiers
     NULLIFIEREXISTS, // Notes & Nullifiers
     EMITNULLIFIER,   // Notes & Nullifiers
-    READL1TOL2MSG,   // Messages
+    L1TOL2MSGEXISTS, // Messages
     HEADERMEMBER,    // Archive tree & Headers
 
     // Accrued Substate

noir-projects/aztec-nr/aztec/src/context/avm.nr

@@ -1,4 +1,4 @@
-use dep::protocol_types::address::{AztecAddress, EthAddress};
+use dep::protocol_types::{address::{AztecAddress, EthAddress}, constants::L1_TO_L2_MESSAGE_LENGTH};
 
 // Getters that will be converted by the transpiler into their
 // own opcodes
@@ -10,6 +10,7 @@ impl AVMContext {
         Self {}
     }
 
+    // OPCODES
     #[oracle(address)]
     pub fn address(self) -> AztecAddress {}
 
@@ -56,16 +57,40 @@ impl AVMContext {
     pub fn emit_note_hash(self, note_hash: Field) {}
 
     #[oracle(nullifierExists)]
-    pub fn check_nullifier_exists(self, nullifier: Field) -> u8 {}
+    pub fn nullifier_exists(self, nullifier: Field) -> u8 {}
 
     #[oracle(emitNullifier)]
     pub fn emit_nullifier(self, nullifier: Field) {}
 
+    #[oracle(l1ToL2MsgExists)]
+    pub fn l1_to_l2_msg_exists(self, msg_hash: Field, msg_leaf_index: Field) -> u8 {}
+
+    #[oracle(sendL2ToL1Msg)]
+    pub fn send_l2_to_l1_msg(self, recipient: EthAddress, content: Field) {}
+
+    ///////////////////////////////////////////////////////////////////////////
     // The functions below allow interface-equivalence with PrivateContext
-    // for emitting note hashes and nullifiers
-    pub fn push_new_note_hash(self: &mut Self, note_hash: Field) {
-        self.emit_note_hash(note_hash);
+    ///////////////////////////////////////////////////////////////////////////
+    pub fn this_address(self) -> AztecAddress {
+        self.address()
+    }
+
+    #[oracle(sendL2ToL1Msg)]
+    pub fn message_portal(&mut self, recipient: EthAddress, content: Field) {}
+
+    pub fn consume_l1_to_l2_message(
+        &mut self,
+        _msg_key: Field,
+        _content: Field,
+        _secret: Field,
+        _sender: EthAddress
+    ) {
+        assert(false, "Not implemented!");
     }
+
+    #[oracle(emitNoteHash)]
+    pub fn push_new_note_hash(self: &mut Self, note_hash: Field) {}
+
     pub fn push_new_nullifier(self: &mut Self, nullifier: Field, _nullified_commitment: Field) {
         // Cannot nullify pending commitments in AVM, so `nullified_commitment` is not used
         self.emit_nullifier(nullifier);

noir-projects/noir-contracts/contracts/avm_test_contract/src/main.nr

@@ -1,6 +1,6 @@
 contract AvmTest {
     // Libs
-    use dep::aztec::protocol_types::address::{AztecAddress, EthAddress};
+    use dep::aztec::protocol_types::{address::{AztecAddress, EthAddress}, constants::L1_TO_L2_MESSAGE_LENGTH};
 
     // avm lib
     use dep::aztec::avm::hash::{keccak256, poseidon, sha256};
@@ -159,15 +159,15 @@ contract AvmTest {
 
     // Use the standard context interface to emit a new nullifier
     #[aztec(public-vm)]
-    fn check_nullifier_exists(nullifier: Field) -> pub u8 {
-        context.check_nullifier_exists(nullifier)
+    fn nullifier_exists(nullifier: Field) -> pub u8 {
+        context.nullifier_exists(nullifier)
     }
 
     // Use the standard context interface to emit a new nullifier
     #[aztec(public-vm)]
     fn emit_nullifier_and_check(nullifier: Field) {
         context.emit_nullifier(nullifier);
-        let exists = context.check_nullifier_exists(nullifier);
+        let exists = context.nullifier_exists(nullifier);
         assert(exists == 1, "Nullifier was just created, but its existence wasn't detected!");
     }
 
@@ -178,4 +178,14 @@ contract AvmTest {
         // Can't do this twice!
         context.push_new_nullifier(nullifier, 0);
     }
+
+    #[aztec(public-vm)]
+    fn l1_to_l2_msg_exists(msg_hash: Field, msg_leaf_index: Field) -> pub u8 {
+        context.l1_to_l2_msg_exists(msg_hash, msg_leaf_index)
+    }
+
+    #[aztec(public-vm)]
+    fn send_l2_to_l1_msg(recipient: EthAddress, content: Field) {
+        context.message_portal(recipient, content)
+    }
 }