TotalSums fix for non-powers of 2

.github/workflows/github-ci.yml

@@ -34,6 +34,7 @@ jobs:
       run:
         shell: bash
     strategy:
+      fail-fast: false
       matrix:
         # TODO: shared builds
         package_build: [ON, OFF]
@@ -50,6 +51,10 @@ jobs:
             hexl: ON
     steps:
       - uses: actions/checkout@v2
+      - name: System Check
+        run: |
+          clang --version
+          gcc -v
       - run: |
           set -x
           env

src/EncryptedArray.cpp

@@ -1,4 +1,4 @@
-/* Copyright (C) 2012-2020 IBM Corp.
+/* Copyright (C) 2012-2022 Intel Corp.
  * This program is Licensed under the Apache License, Version 2.0
  * (the "License"); you may not use this file except in compliance
  * with the License. You may obtain a copy of the License at
@@ -707,32 +707,32 @@ void runningSums(const EncryptedArray& ea, Ctxt& ctxt)
 
 void totalSums(const EncryptedArray& ea, Ctxt& ctxt)
 {
-  long n = ea.size();
+  long n = ea.size(); // slot-count
 
   if (n == 1)
     return;
 
   Ctxt orig = ctxt;
-
-  long k = NTL::NumBits(n);
+  
+  long b = NTL::NumBits(n);
   long e = 1;
 
-  for (long i = k - 2; i >= 0; i--) {
-    Ctxt tmp1 = ctxt;
-    ea.rotate(tmp1, e);
-    ctxt += tmp1; // ctxt = ctxt + (ctxt >>> e)
+  for (long i = b - 2; i >= 0; i--) {
+
+    Ctxt tmp1 = orig;
+    helib::rotate(tmp1, e);
+    orig += tmp1;
     e = 2 * e;
 
     if (NTL::bit(n, i)) {
       Ctxt tmp2 = orig;
-      ea.rotate(tmp2, e);
-      ctxt += tmp2; // ctxt = ctxt + (orig >>> e)
-                    // NOTE: we could have also computed
-                    // ctxt =  (ctxt >>> e) + orig, however,
-                    // this would give us greater depth/noise
+      helib::rotate(tmp2, 1);
+      tmp2 += ctxt;
+      orig = tmp2;
       e += 1;
     }
   }
+  ctxt = orig;
 }
 
 // Linearized polynomials.

tests/CMakeLists.txt

@@ -30,6 +30,7 @@ if (NOT ONLY_ADD_TEST)
         "TestClonedPtr.cpp"
         "TestContext.cpp"
         "TestCtxt.cpp"
+        "TestEncryptedArray.cpp"
         "TestErrorHandling.cpp"
         "TestHEXL.cpp"
         "TestLogging.cpp"
@@ -148,6 +149,7 @@ set(TEST_NAMES
     "TestClonedPtr"
     "TestContext"
     "TestCtxt"
+    "TestEncryptedArray"
     "TestErrorHandling"
     "TestFatBootstrappingWithMultiplications"
     "TestHEXL"