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authorEelco Dolstra <e.dolstra@tudelft.nl>2006-05-03 23:17:42 +0000
committerEelco Dolstra <e.dolstra@tudelft.nl>2006-05-03 23:17:42 +0000
commitb803fb95cbce33cf37496e1fc947d9721714de44 (patch)
tree2d1d165e04eb08da4dc49b003c5b866dce2c2c9e
parentdb0d865ec4fb646856731000d540d968011f4daf (diff)
* Maintain the count field properly.
-rw-r--r--table/aterm-map.cc73
1 files changed, 44 insertions, 29 deletions
diff --git a/table/aterm-map.cc b/table/aterm-map.cc
index 465cabf34..aa7149841 100644
--- a/table/aterm-map.cc
+++ b/table/aterm-map.cc
@@ -23,7 +23,7 @@ private:
KeyValue * hashTable;
/* Current size of the hash table. */
- unsigned int size;
+ unsigned int capacity;
/* Number of elements in the hash table. */
unsigned int count;
@@ -49,6 +49,8 @@ public:
void remove(ATerm key);
+ unsigned int size();
+
private:
void init(unsigned int expectedCount);
@@ -56,7 +58,7 @@ private:
void resizeTable(unsigned int expectedCount);
- void copy(KeyValue * elements, unsigned int size);
+ void copy(KeyValue * elements, unsigned int capacity);
inline unsigned int hash1(ATerm key) const;
inline unsigned int hash2(ATerm key) const;
@@ -72,7 +74,7 @@ ATermMap::ATermMap(unsigned int expectedCount)
ATermMap::ATermMap(const ATermMap & map)
{
init(map.maxCount);
- copy(map.hashTable, map.size);
+ copy(map.hashTable, map.capacity);
}
@@ -81,7 +83,7 @@ ATermMap & ATermMap::operator = (const ATermMap & map)
if (this == &map) return *this;
free();
init(map.maxCount);
- copy(map.hashTable, map.size);
+ copy(map.hashTable, map.capacity);
return *this;
}
@@ -95,7 +97,7 @@ ATermMap::~ATermMap()
void ATermMap::init(unsigned int expectedCount)
{
assert(sizeof(ATerm) * 2 == sizeof(KeyValue));
- size = 0;
+ capacity = 0;
count = 0;
maxCount = 0;
hashTable = 0;
@@ -133,20 +135,20 @@ void ATermMap::resizeTable(unsigned int expectedCount)
// cout << maxCount << " " << size << endl;
// cout << (double) size / maxCount << endl;
- unsigned int oldSize = size;
+ unsigned int oldCapacity = capacity;
KeyValue * oldHashTable = hashTable;
maxCount = expectedCount;
- size = roundToPowerOf2(maxCount * maxLoadFactor);
- hashTable = (KeyValue *) calloc(sizeof(KeyValue), size);
- ATprotectArray((ATerm *) hashTable, size * 2);
+ capacity = roundToPowerOf2(maxCount * maxLoadFactor);
+ hashTable = (KeyValue *) calloc(sizeof(KeyValue), capacity);
+ ATprotectArray((ATerm *) hashTable, capacity * 2);
-// cout << size << endl;
+// cout << capacity << endl;
/* Re-hash the elements in the old table. */
- if (oldSize != 0) {
+ if (oldCapacity != 0) {
count = 0;
- copy(oldHashTable, oldSize);
+ copy(oldHashTable, oldCapacity);
ATunprotectArray((ATerm *) oldHashTable);
::free(oldHashTable);
nrResizes++;
@@ -154,9 +156,9 @@ void ATermMap::resizeTable(unsigned int expectedCount)
}
-void ATermMap::copy(KeyValue * elements, unsigned int size)
+void ATermMap::copy(KeyValue * elements, unsigned int capacity)
{
- for (unsigned int i = 0; i < size; ++i)
+ for (unsigned int i = 0; i < capacity; ++i)
if (elements[i].value) /* i.e., non-empty, non-deleted element */
set(elements[i].key, elements[i].value);
}
@@ -174,10 +176,10 @@ unsigned int ATermMap::hash1(ATerm key) const
/* Approximately equal to:
double d = key2 * 0.6180339887;
- unsigned int h = (int) (size * (d - floor(d)));
+ unsigned int h = (int) (capacity * (d - floor(d)));
*/
- unsigned int h = (size * ((key2 * knuth) & ((1 << shift) - 1))) >> shift;
+ unsigned int h = (capacity * ((key2 * knuth) & ((1 << shift) - 1))) >> shift;
return h;
}
@@ -186,9 +188,10 @@ unsigned int ATermMap::hash1(ATerm key) const
unsigned int ATermMap::hash2(ATerm key) const
{
unsigned int key2 = ((unsigned int) key) >> 2;
- /* Note: the result must be relatively prime to `size' (which is a
- power of 2), so we make sure that the result is always odd. */
- unsigned int h = ((key2 * 134217689) & (size - 1)) | 1;
+ /* Note: the result must be relatively prime to `capacity' (which
+ is a power of 2), so we make sure that the result is always
+ odd. */
+ unsigned int h = ((key2 * 134217689) & (capacity - 1)) | 1;
return h;
}
@@ -199,21 +202,21 @@ static unsigned int nrSetProbes = 0;
void ATermMap::set(ATerm key, ATerm value)
{
- if (count == maxCount) resizeTable(size * 2 / maxLoadFactor);
+ if (count == maxCount) resizeTable(capacity * 2 / maxLoadFactor);
nrItemsSet++;
- for (unsigned int i = 0, h = hash1(key); i < size;
- ++i, h = (h + hash2(key)) & (size - 1))
+ for (unsigned int i = 0, h = hash1(key); i < capacity;
+ ++i, h = (h + hash2(key)) & (capacity - 1))
{
- // assert(h < size);
+ // assert(h < capacity);
nrSetProbes++;
/* Note: to see whether a slot is free, we check
hashTable[h].value, not hashTable[h].key, since we use
value == 0 to mark deleted slots. */
if (hashTable[h].value == 0 || hashTable[h].key == key) {
+ if (hashTable[h].value == 0) count++;
hashTable[h].key = key;
hashTable[h].value = value;
- count++;
return;
}
}
@@ -229,8 +232,8 @@ static unsigned int nrGetProbes = 0;
ATerm ATermMap::get(ATerm key) const
{
nrItemsGet++;
- for (unsigned int i = 0, h = hash1(key); i < size;
- ++i, h = (h + hash2(key)) & (size - 1))
+ for (unsigned int i = 0, h = hash1(key); i < capacity;
+ ++i, h = (h + hash2(key)) & (capacity - 1))
{
nrGetProbes++;
if (hashTable[h].key == 0) return 0;
@@ -242,18 +245,27 @@ ATerm ATermMap::get(ATerm key) const
void ATermMap::remove(ATerm key)
{
- for (unsigned int i = 0, h = hash1(key); i < size;
- ++i, h = (h + hash2(key)) & (size - 1))
+ for (unsigned int i = 0, h = hash1(key); i < capacity;
+ ++i, h = (h + hash2(key)) & (capacity - 1))
{
if (hashTable[h].key == 0) return;
if (hashTable[h].key == key) {
- hashTable[h].value = 0;
+ if (hashTable[h].value != 0) {
+ hashTable[h].value = 0;
+ count--;
+ }
return;
}
}
}
+unsigned int ATermMap::size()
+{
+ return count; /* STL nomenclature */
+}
+
+
int main(int argc, char * * argv)
{
ATerm bottomOfStack;
@@ -295,8 +307,11 @@ int main(int argc, char * * argv)
map.set(keys[i], values[i]);
// cerr << "INSERT: " << keys[i] << " " << values[i] << endl;
}
+ unsigned int size = map.size();
+ assert(size <= n);
values[n - 1] = 0;
map.remove(keys[n - 1]);
+ assert(map.size() == size - 1);
for (unsigned int i = 0; i < n; ++i) {
if (map.get(keys[i]) != values[i]) {
for (unsigned int j = i + 1; j < n; ++j)