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gpi.hpp
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33 
34 #include <cmath>
35 
36 namespace Gecode { namespace Kernel {
37 
39  class GPI {
40  public:
42  class Info {
43  public:
45  unsigned int pid;
47  unsigned int gid;
49  double afc;
51  void init(unsigned int pid, unsigned int gid);
52  };
53  private:
55  class Block : public HeapAllocated {
56  public:
58  static const int n_info = 8192;
60  Info info[n_info];
62  Block* next;
64  int free;
66  Block(void);
68  void rescale(void);
69  };
71  Block* b;
73  double invd;
75  unsigned int npid;
77  bool us;
79  Block fst;
82  public:
84  GPI(void);
86  void decay(double d);
88  double decay(void) const;
90  void fail(Info& c);
92  Info* allocate(unsigned int p, unsigned int gid);
94  Info* allocate(unsigned int gid);
96  unsigned int pid(void) const;
98  bool unshare(void);
100  ~GPI(void);
101  };
102 
103 
104  forceinline void
105  GPI::Info::init(unsigned int pid0, unsigned int gid0) {
106  pid=pid0; gid=gid0; afc=1.0;
107  }
108 
109 
111  GPI::Block::Block(void)
112  : next(NULL), free(n_info) {}
113 
114  forceinline void
115  GPI::Block::rescale(void) {
116  for (int i=free; i < n_info; i++)
117  info[i].afc *= Kernel::Config::rescale;
118  }
119 
120 
122  GPI::GPI(void)
123  : b(&fst), invd(1.0), npid(0U), us(false) {}
124 
125  forceinline void
127  m.acquire();
128  c.afc = invd * (c.afc + 1.0);
130  for (Block* i = b; i != NULL; i = i->next)
131  i->rescale();
132  m.release();
133  }
134 
135  forceinline double
136  GPI::decay(void) const {
137  double d;
138  const_cast<GPI&>(*this).m.acquire();
139  d = 1.0 / invd;
140  const_cast<GPI&>(*this).m.release();
141  return d;
142  }
143 
144  forceinline unsigned int
145  GPI::pid(void) const {
146  unsigned int p;
147  const_cast<GPI&>(*this).m.acquire();
148  p = npid;
149  const_cast<GPI&>(*this).m.release();
150  return p;
151  }
152 
153  forceinline bool
154  GPI::unshare(void) {
155  bool u;
156  m.acquire();
157  u = us; us = true;
158  m.release();
159  return u;
160  }
161 
162  forceinline void
163  GPI::decay(double d) {
164  m.acquire();
165  invd = 1.0 / d;
166  m.release();
167  }
168 
170  GPI::allocate(unsigned int p, unsigned int gid) {
171  Info* c;
172  m.acquire();
173  if (b->free == 0) {
174  Block* n = new Block;
175  n->next = b; b = n;
176  }
177  c = &b->info[--b->free];
178  m.release();
179  c->init(p,gid);
180  return c;
181  }
182 
184  GPI::allocate(unsigned int gid) {
185  Info* c;
186  m.acquire();
187  if (b->free == 0) {
188  Block* n = new Block;
189  n->next = b; b = n;
190  }
191  c = &b->info[--b->free];
192  c->init(npid++,gid);
193  m.release();
194  return c;
195  }
196 
198  GPI::~GPI(void) {
199  Block* n = b;
200  while (n != &fst) {
201  Block* d = n;
202  n = n->next;
203  delete d;
204  }
205  }
206 
207 }}
208 
209 // STATISTICS: kernel-prop
Info * allocate(unsigned int p, unsigned int gid)
Allocate info for existing propagator with pid p.
Definition: gpi.hpp:170
void acquire(void)
Acquire the mutex and possibly block.
Definition: none.hpp:42
void fail(Info &c)
Increment failure count.
Definition: gpi.hpp:126
unsigned int pid
Propagator identifier.
Definition: gpi.hpp:45
Global propagator information.
Definition: gpi.hpp:39
bool unshare(void)
Provide access to unshare info and set to true.
Definition: gpi.hpp:154
unsigned int pid(void) const
Return next free propagator id.
Definition: gpi.hpp:145
double decay(void) const
Return decay factor.
Definition: gpi.hpp:136
GPI(void)
Initialize.
Definition: gpi.hpp:122
Gecode toplevel namespace
union Gecode::@602::NNF::@65 u
Union depending on nodetype t.
unsigned int gid
Group identifier.
Definition: gpi.hpp:47
#define GECODE_KERNEL_EXPORT
Definition: kernel.hh:70
Base class for heap allocated objects.
Definition: heap.hpp:340
void init(unsigned int pid, unsigned int gid)
Initialize.
Definition: gpi.hpp:105
AFC afc
Definition: afc.cpp:135
double afc
The afc value.
Definition: gpi.hpp:49
Gecode::IntSet d(v, 7)
Class for storing propagator information.
Definition: gpi.hpp:42
#define forceinline
Definition: config.hpp:185
Gecode::FloatVal c(-8, 8)
void release(void)
Release the mutex.
Definition: none.hpp:48
A mutex for mutual exclausion among several threads.
Definition: thread.hpp:96
int n
Number of negative literals for node type.
Definition: bool-expr.cpp:234
~GPI(void)
Delete.
Definition: gpi.hpp:198
Gecode::IntArgs i({1, 2, 3, 4})
int p
Number of positive literals for node type.
Definition: bool-expr.cpp:232
const double rescale
Rescale factor for action and afc values.
Definition: kernel.hh:99
const double rescale_limit
Rescale action and afc values when larger than this.
Definition: kernel.hh:101