Cleaning up the CG reproduciblity test. More info reported

lib/Bitwise.h

@@ -0,0 +1,59 @@
+/*************************************************************************************
+
+Grid physics library, www.github.com/paboyle/Grid
+
+Source file: ./lib/Bitwise.h
+
+Copyright (C) 2016
+
+Author: Guido Cossu <guido.cossu@ed.ac.uk>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License along
+with this program; if not, write to the Free Software Foundation, Inc.,
+51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+See the full license in the file "LICENSE" in the top level distribution
+directory
+*************************************************************************************/
+/*  END LEGAL */
+#ifndef GRID_BITWISE_H
+#define GRID_BITWISE_H
+
+#include <bitset>
+#include <climits>
+
+namespace Grid {
+
+void show_binaryrep(const unsigned char* a, size_t size);
+
+template <typename T>
+void show_binaryrep(const T& a) {
+  const char* beg = reinterpret_cast<const char*>(&a);
+  const char* end = beg + sizeof(a);
+  while (beg != end) std::cout << std::bitset<CHAR_BIT>(*beg++) << ' ';
+  std::cout << '\n';
+}
+
+template <typename T>
+void bitwise_xor(T& l, T& r, unsigned char* xors) {
+  assert(sizeof(l) == sizeof(r));
+  unsigned char* org = reinterpret_cast<unsigned char*>(&l);
+  unsigned char* cur = reinterpret_cast<unsigned char*>(&r);
+  int words = sizeof(l) / sizeof(*org);
+  unsigned char result = 0;
+  for (int w = 0; w < words; w++) xors[w] = (org[w] ^ cur[w]);
+}
+
+}; // namespace 
+
+#endif