Mozilla/mozilla/js/tamarin/core/avmplusHashtable.h
gerv%gerv.net 0a3a70857a Bug 236613: fix formatting of MPL/LGPL/GPL tri-license.
git-svn-id: svn://10.0.0.236/trunk@220064 18797224-902f-48f8-a5cc-f745e15eee43
2007-02-13 18:05:02 +00:00

296 lines
7.6 KiB
C++

/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is [Open Source Virtual Machine.].
*
* The Initial Developer of the Original Code is
* Adobe System Incorporated.
* Portions created by the Initial Developer are Copyright (C) 2004-2006
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Adobe AS3 Team
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#ifndef __avmplus_Hashtable__
#define __avmplus_Hashtable__
namespace avmplus
{
/**
* common base class for hashtable-like objects.
*/
class Hashtable : public MMgc::GCFinalizedObject
{
public:
/**
* since identifiers are always interned strings, they can't be 0,
* so we can use 0 as the empty value.
*/
const static Atom EMPTY = 0;
/** DELETED is stored as the key for deleted items5 */
const static Atom DELETED = undefinedAtom;
/** kDefaultCapacity must be a power of 2 */
const static int kDefaultCapacity = 8;
int getSize() const { return size; }
int getNumAtoms() const { return logNumAtoms ? 1<<(logNumAtoms-1) : 0; }
bool hasDontEnumSupport() const { return flags & kDontEnumSupport; }
void setDontEnumSupport(bool flag) { flags = (short)((flags & ~kDontEnumSupport) | (flag ? kDontEnumSupport : 0)); }
int dontEnumMask() const { return hasDontEnumSupport() ? kDontEnumBit : 0; }
bool getAtomPropertyIsEnumerable(Atom name) const;
void setAtomPropertyIsEnumerable(Atom name, bool enumerable);
// kDontEnumBit is or'd into atoms to indicate that the property is {DontEnum}
enum
{
kDontEnumBit = 1
};
private:
int size;
short logNumAtoms;
short flags;
// Flags used in the "flags" variable
enum
{
kDontEnumSupport = 1,
kHasDeletedItems = 2
};
bool hasDeletedItems() const { return (flags & kHasDeletedItems) != 0; }
void setNumAtoms(int numAtoms)
{
logNumAtoms = numAtoms ? (short)(FindOneBit(numAtoms)+1) : 0;
AvmAssert(getNumAtoms() == numAtoms);
}
#if defined(AVMPLUS_IA32) || defined(AVMPLUS_AMD64)
static inline uint32 FindOneBit(uint32 value)
{
#ifndef __GNUC__
_asm
{
bsr eax,[value];
}
#else
// DBC - This gets rid of a compiler warning and matchs PPC results where value = 0
register int result = ~0;
if (value)
{
asm (
"bsr %1, %0"
: "=r" (result)
: "m"(value)
);
}
return result;
#endif
}
#elif defined(AVMPLUS_PPC)
static inline int FindOneBit(uint32 value)
{
register int index;
#ifdef DARWIN
asm ("cntlzw %0,%1" : "=r" (index) : "r" (value));
#else
register uint32 in = value;
asm { cntlzw index, in; }
#endif
return 31-index;
}
#else // generic platform
static int FindOneBit(uint32 value)
{
for (int i=0; i < 32; i++)
if (value & (1<<i))
return i;
// asm versions of this function are undefined if no bits are set
AvmAssert(false);
return 0;
}
#endif
void setAtoms(Atom *atoms);
protected:
/** property hashtable, this has no DWB on purpose, setAtoms contains the WB */
Atom* atoms;
public:
Atom* getAtoms() { return atoms; }
/**
* initialize with a known capacity. i.e. we can fit minSize
* elements in without rehashing.
* @param heap
* @param capacity # of logical slots
*/
Hashtable(MMgc::GC *gc, int capacity = kDefaultCapacity)
{
initialize(gc, capacity);
}
void destroy();
void reset()
{
MMgc::GC *gc = MMgc::GC::GetGC(atoms);
destroy();
initialize(gc);
}
void initialize(MMgc::GC *gc, int capacity = kDefaultCapacity);
virtual ~Hashtable();
/* See CPP for load factor variants. */
bool isFull() const;
/**
* @name operations on name/value pairs
*/
/*@{*/
void put(Atom name, Atom value);
Atom get(Atom name) const;
Atom remove(Atom name);
bool contains(Atom name) const
{
return (atoms[find(name, atoms, getNumAtoms())] & ~dontEnumMask()) == name;
}
/*@}*/
/**
* convenience functions for storing pointers as values. This is
* safe for internal tables that always store the same kind of
* pointer.
*/
/*@{*/
void put(Atom name, const void *value)
{
put(name,(Atom)value);
}
void add(Atom name, const void *value)
{
add(name, (Atom)value);
};
/*@}*/
/**
* Finds the hash bucket corresponding to the key x
* in the hash table starting at t, containing tLen
* atoms.
*
* This is a quadratic probe, but we only hit even-numbered
* slots since those hold keys.
*/
int find(Atom x, const Atom *t, unsigned tLen) const;
int find(Stringp x, const Atom *t, unsigned tLen) const;
int find(Atom x) const { return find(x, atoms, getNumAtoms()); }
/**
* Adds a name/value pair to a hash table. Automatically
* grows the hash table if it is full.
*/
void add (Atom name, Atom value);
/**
* Called to grow the Hashtable, particularly by add.
*
* - Calculates the needed size for the new Hashtable
* (typically 2X the current size)
* - Creates a new array of Atoms
* - Rehashes the current table into the new one
* - Deletes the old array of Atoms and sets the Atom
* pointer to our new array of Atoms
*/
void grow();
/**
* Allow caller to enumerate all entries in the table.
*/
int next(int index);
Atom keyAt(int index);
Atom valueAt(int index);
//void removeAt(int index);
void setHasDeletedItems(bool val) { flags = (short)((flags & ~kHasDeletedItems) | (val ? kHasDeletedItems : 0)); }
protected:
int rehash(Atom *oldAtoms, int oldlen, Atom *newAtoms, int newlen);
};
/**
* If key is an object weak ref's are used
*/
class WeakKeyHashtable : public Hashtable
{
public:
WeakKeyHashtable (MMgc::GC* gc): Hashtable(gc) { };
void add(Atom key, Atom value);
Atom get(Atom key) { return Hashtable::get(getKey(key)); }
void remove(Atom key) { Hashtable::remove(getKey(key)); }
bool contains(Atom key) { return Hashtable::contains(getKey(key)); }
private:
Atom getKey(Atom key);
void prune();
};
/**
* If key is an object weak ref's are used
*/
class WeakValueHashtable : public Hashtable
{
public:
WeakValueHashtable (MMgc::GC* gc): Hashtable(gc) { };
void add(Atom key, Atom value);
Atom get(Atom key) { return getValue(key, Hashtable::get(key)); }
Atom remove(Atom key) { return getValue(key, Hashtable::remove(key)); }
private:
Atom getValue(Atom key, Atom value);
void prune();
};
}
#endif /* __avmplus_Hashtable__ */