From ad04340972f3d35a8d4915227d15c5502af7fe63 Mon Sep 17 00:00:00 2001
From: Anton <14254374+0xmad@users.noreply.github.com>
Date: Fri, 19 Jul 2024 14:37:12 -0500
Subject: [PATCH] chore(circuits): optimize message to command (#1682)

---
 .../circom/trees/incrementalQuinaryTree.circom  | 17 +++++++++++++++--
 circuits/circom/utils/messageToCommand.circom   |  6 +-----
 circuits/circom/utils/verifySignature.circom    |  5 +----
 3 files changed, 17 insertions(+), 11 deletions(-)

diff --git a/circuits/circom/trees/incrementalQuinaryTree.circom b/circuits/circom/trees/incrementalQuinaryTree.circom
index 377fe95c95..a3b903017d 100644
--- a/circuits/circom/trees/incrementalQuinaryTree.circom
+++ b/circuits/circom/trees/incrementalQuinaryTree.circom
@@ -93,6 +93,13 @@ template Splicer(numItems) {
     // The output signal from the QuinSelector is <item from in> and gets
     // wired to Mux1 (as above).
 
+    var inputs[NUM_OUTPUT_ITEMS];
+
+    for (var i = 0; i < numItems; i++) {
+        inputs[i] = in[i];
+    }
+    inputs[NUM_OUTPUT_ITEMS - 1] = 0;
+
     for (var i = 0; i < NUM_OUTPUT_ITEMS; i++) {
         // Determines if current index is greater than the insertion index.
         var computedIsIndexAfterInsertPoint = SafeGreaterThan(3)([i, index]);
@@ -101,7 +108,7 @@ template Splicer(numItems) {
         var computedAdjustedIndex = i - computedIsIndexAfterInsertPoint;
 
         // Selects item from the original array or the leaf for insertion.
-        var computedQuinSelected = QuinSelector(NUM_OUTPUT_ITEMS)([in[0], in[1], in[2], in[3], 0], computedAdjustedIndex);
+        var computedQuinSelected = QuinSelector(NUM_OUTPUT_ITEMS)(inputs, computedAdjustedIndex);
         var computedIsIndexEqual = IsEqual()([index, i]);
         var mux = Mux1()([computedQuinSelected, leaf], computedIsIndexEqual);
 
@@ -129,8 +136,14 @@ template QuinTreeInclusionProof(levels) {
 
     // Iteratively hash each level of path_elements with the leaf or previous hash
     for (var i = 0; i < levels; i++) {
+        var elements[LEAVES_PER_PATH_LEVEL];
+
+        for (var j = 0; j < LEAVES_PER_PATH_LEVEL; j++) {
+            elements[j] = path_elements[i][j];
+        }
+
         var computedSplicedLeaf[LEAVES_PER_NODE] = Splicer(LEAVES_PER_PATH_LEVEL)(
-            [path_elements[i][0], path_elements[i][1], path_elements[i][2], path_elements[i][3]], 
+            elements, 
             currentLeaf, 
             path_index[i]
         );
diff --git a/circuits/circom/utils/messageToCommand.circom b/circuits/circom/utils/messageToCommand.circom
index 70af685387..a9113269e6 100644
--- a/circuits/circom/utils/messageToCommand.circom
+++ b/circuits/circom/utils/messageToCommand.circom
@@ -46,11 +46,7 @@ template MessageToCommand() {
 
     // Decrypt the message using Poseidon decryption.
     var computedDecryptor[DECRYPTED_LENGTH] = PoseidonDecryptWithoutCheck(MSG_LENGTH)(
-        [
-            message[0], message[1], message[2], message[3],
-            message[4], message[5], message[6], message[7],
-            message[8], message[9]            
-        ],
+        message,
         0, 
         computedEcdh
     );
diff --git a/circuits/circom/utils/verifySignature.circom b/circuits/circom/utils/verifySignature.circom
index dcc42c08aa..83deef7ba7 100644
--- a/circuits/circom/utils/verifySignature.circom
+++ b/circuits/circom/utils/verifySignature.circom
@@ -32,10 +32,7 @@ template EdDSAPoseidonVerifier_patched() {
     // convert the signature scalar S into its binary representation.
     var computedNum2Bits[254] = Num2Bits(254)(S);
 
-    var computedCompConstantIn[254];
-    for (var i=0; i<253; i++) {
-        computedCompConstantIn[i] = computedNum2Bits[i];
-    }
+    var computedCompConstantIn[254] = computedNum2Bits;
     computedCompConstantIn[253] = 0;
 
     // A component that ensures S is within a valid range,