From 2f28fc70023e0c9b8f51b6fcbb6de7f6b6474512 Mon Sep 17 00:00:00 2001
From: Jordi Baylina <jordi@baylina.cat>
Date: Thu, 23 Jan 2020 07:23:17 +0700
Subject: [PATCH] remove pows and shifts for optimization

---
 circuits/binsum.circom |  11 +-
 circuits/bitify.circom |   8 +-
 test/circuits/in.json  | 260 ++++++++++++++++++++++++++++++++++++++++-
 3 files changed, 273 insertions(+), 6 deletions(-)

diff --git a/circuits/binsum.circom b/circuits/binsum.circom
index 3783e26..6fd79ad 100644
--- a/circuits/binsum.circom
+++ b/circuits/binsum.circom
@@ -72,19 +72,26 @@ template BinSum(n, ops) {
     var k;
     var j;
 
+    var e2;
+
+    e2 = 1;
     for (k=0; k<n; k++) {
         for (j=0; j<ops; j++) {
-            lin += in[j][k] * 2**k;
+            lin += in[j][k] * e2;
         }
+        e2 = e2 + e2;
     }
 
+    e2 = 1;
     for (k=0; k<nout; k++) {
         out[k] <-- (lin >> k) & 1;
 
         // Ensure out is binary
         out[k] * (out[k] - 1) === 0;
 
-        lout += out[k] * 2**k;
+        lout += out[k] * e2;
+
+        e2 = e2+e2;
     }
 
     // Ensure the sum;
diff --git a/circuits/bitify.circom b/circuits/bitify.circom
index 2050e13..60fb89c 100644
--- a/circuits/bitify.circom
+++ b/circuits/bitify.circom
@@ -26,10 +26,12 @@ template Num2Bits(n) {
     signal output out[n];
     var lc1=0;
 
+    var e2=1;
     for (var i = 0; i<n; i++) {
         out[i] <-- (in >> i) & 1;
         out[i] * (out[i] -1 ) === 0;
-        lc1 += out[i] * 2**i;
+        lc1 += out[i] * e2;
+        e2 = e2+e2;
     }
 
     lc1 === in;
@@ -54,8 +56,10 @@ template Bits2Num(n) {
     signal output out;
     var lc1=0;
 
+    var e2 = 1;
     for (var i = 0; i<n; i++) {
-        lc1 += in[i] * 2**i;
+        lc1 += in[i] * e2;
+        e2 = e2 + e2;
     }
 
     lc1 ==> out;
diff --git a/test/circuits/in.json b/test/circuits/in.json
index 89d127c..2ebe0d5 100644
--- a/test/circuits/in.json
+++ b/test/circuits/in.json
@@ -1,2 +1,258 @@
-{"enabled":1,"Ax":"13277427435165878497778222415993513565335242147425444199013288855685581939618","Ay":"13622229784656158136036771217484571176836296686641868549125388198837476602820","R8x":"11220723668893468001994760120794694848178115379170651044669708829805665054484","R8y":"2367470421002446880004241260470975644531657398480773647535134774673409612366","S":"1307100909096544936550139783786226891472336052773077686618468233418583414320","M":"1234"}
-
+{
+ "in": [
+  "1",
+  "1",
+  "1",
+  "1",
+  "1",
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+  "1",
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+}
\ No newline at end of file