bitvect: implement a dynamic bit-vector class.

* src/misc/bitvect.cc, src/misc/bitvect.hh: New files.
* src/misc/Makefile.am: Add them.
* src/tgbatest/bitvect.cc, src/tgbatest/bitvect.test: New files.
* src/tgbatest/Makefile.am: Add them.

src/misc/bitvect.cc

@@ -0,0 +1,176 @@
+// -*- coding: utf-8 -*-
+// Copyright (C) 2013 Laboratoire de Recherche et Développement
+// de l'Epita (LRDE).
+//
+// This file is part of Spot, a model checking library.
+//
+// Spot 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 3 of the License, or
+// (at your option) any later version.
+//
+// Spot 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, see <http://www.gnu.org/licenses/>.
+
+#ifdef HAVE_CONFIG_H
+#  include "config.h"
+#endif
+#include "bitvect.hh"
+#include <new>
+#include <iostream>
+#include <cmath>
+#include <hashfunc.hh>
+#include <cstring>
+
+namespace spot
+{
+  namespace
+  {
+
+    // How many block_t do we need to store BITCOUNT bits?
+    size_t block_needed(size_t bitcount)
+    {
+      const size_t bpb = 8 * sizeof(bitvect::block_t);
+      size_t n = (bitcount + bpb - 1) / bpb;
+      if (n < 1)
+	return 1;
+      return n;
+    }
+
+    // Fowler–Noll–Vo hash parameters for 64bits
+    template<int numbytes>
+    struct fnv
+    {
+      static unsigned long init()
+      {
+	return 14695981039346656037UL;
+      }
+
+      static unsigned long prime()
+      {
+	return 1099511628211UL;
+      }
+    };
+
+    // Fowler–Noll–Vo hash parameters for 32bits
+    template<>
+    struct fnv<4>
+    {
+      static unsigned int init()
+      {
+	return 2166136261U;
+      }
+
+      static unsigned int prime()
+      {
+	return 16777619U;
+      }
+    };
+
+  }
+
+  bitvect::bitvect(size_t size, size_t block_count):
+    size_(size),
+    block_count_(block_count),
+    storage_(&local_storage_)
+  {
+    clear_all();
+  }
+
+  bitvect::bitvect(size_t size, size_t block_count, bool):
+    size_(size),
+    block_count_(block_count),
+    storage_(&local_storage_)
+  {
+  }
+
+  bitvect* bitvect::clone() const
+  {
+    size_t n = block_needed(size_);
+    // Allocate some memory for the bitvect.  The instance
+    // already contains one int of local_storage_, but
+    // we allocate n-1 more so that we store the table.
+    void* mem = operator new(sizeof(bitvect)
+			     + (n - 1) * sizeof(bitvect::block_t));
+    bitvect* res = new(mem) bitvect(size_, n, true);
+    memcpy(res->storage_, storage_, res->block_count_ * sizeof(block_t));
+    return res;
+  }
+
+  size_t bitvect::hash() const
+  {
+
+    block_t res = fnv<sizeof(block_t)>::init();
+    size_t i;
+    for (i = 0; i < block_count_ - 1; ++i)
+      {
+	res ^= storage_[i];
+	res *= fnv<sizeof(block_t)>::prime();
+      }
+    // Deal with the last block, that might not be fully used.
+    // Compute the number n of bits used in the last block.
+    const size_t bpb = 8 * sizeof(bitvect::block_t);
+    size_t n = size() % bpb;
+    // Use only the least n bits from storage_[i].
+    res ^= storage_[i] & ((1UL << n) - 1);
+    return res;
+  }
+
+  bitvect* make_bitvect(size_t bitcount)
+  {
+    size_t n = block_needed(bitcount);
+    // Allocate some memory for the bitvect.  The instance
+    // already contains one int of local_storage_, but
+    // we allocate n-1 more so that we store the table.
+    void* mem = operator new(sizeof(bitvect)
+			     + (n - 1) * sizeof(bitvect::block_t));
+    return new(mem) bitvect(bitcount, n);
+  }
+
+
+  bitvect_array* make_bitvect_array(size_t bitcount, size_t vectcount)
+  {
+     size_t n = block_needed(bitcount);
+     // Size of one bitvect.
+     size_t bvsize = sizeof(bitvect) + (n - 1) * sizeof(bitvect::block_t);
+     // Allocate the bitvect_array with enough space at the end
+     // to store all bitvect instances.
+     void* mem = operator new(sizeof(bitvect_array) + bvsize * vectcount);
+     bitvect_array* bva = new(mem) bitvect_array(vectcount, bvsize);
+     // Initialize all the bitvect instances.
+     for (size_t i = 0; i < vectcount; ++i)
+       new(bva->storage_ + i * bvsize) bitvect(bitcount, n);
+     return bva;
+  }
+
+  std::ostream& operator<<(std::ostream& os , const bitvect& v)
+  {
+    for (size_t i = 0, end = v.size(); i != end; ++i)
+      os << (v.get(i) ? '1' : '0');
+    return os;
+  }
+
+  std::ostream& operator<<(std::ostream& os , const bitvect_array& a)
+  {
+    size_t end = a.size();
+    if (end == 0)
+      {
+	os << "empty\n";
+	return os;
+      }
+    int w = floor(log10(end - 1)) + 1;
+    for (size_t i = 0; i != end; ++i)
+      {
+	os.width(w);
+	os << i;
+	os.width(1);
+	os << ": " << a.at(i) << "\n";
+      }
+    return os;
+  }
+}