+++ /dev/null
-/************************************************************************
- ************************************************************************
- FAUST compiler
- Copyright (C) 2003-2004 GRAME, Centre National de Creation Musicale
- ---------------------------------------------------------------------
- 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., 675 Mass Ave, Cambridge, MA 02139, USA.
- ************************************************************************
- ************************************************************************/
-
-
-/*****************************************************************************
-******************************************************************************/
-
-/** \file tree.hh
- * A tree library with hashconsing and maximal sharing capabilities.
- *
- * A tree library with hashconsing and maximal sharing capabilities.
- *
- * <b>API:</b>
- *
- * \li tree (n) : tree of node n with no branch
- * \li tree (n, t1) : tree of node n with a branch t
- * \li tree (n, t1,...,tm) : tree of node n with m branches t1,...,tm
- *
- * <b>Useful conversions :</b>
- *
- * \li int tree2int (t) : if t has a node of type int, return it otherwise error
- * \li float tree2float (t) : if t has a node of type float, return it otherwise error
- * \li const char* tree2str (t) : if t has a node of type symbol, return its name otherwise error
- * \li void* tree2ptr (t) : if t has a node of type ptr, return it otherwise error
- *
- * <b>Pattern matching :</b>
- *
- * \li if (isTree (t, n)) ... : t has node n and no branches;
- * \li if (isTree (t, n, &t1) ... : t has node n and 1 branch, t1 is set accordingly;
- * \li if (isTree (t, n, &t1...&tm)... : t has node n and m branches, ti's are set accordingly;
- *
- * <b>Accessors :</b>
- *
- * \li t->node() : the node of t { return fNode; }
- * \li t->height() : lambda height such that H(x)=0, H(\x.e)=1+H(e), H(e*f)=max(H(e),H(f))
- * \li t->arity() : the number of branches of t { return fArity; }
- * \li t->branch(i) : the ith branch of t
- *
- * <b>Attributs :</b>
- *
- * \li t->attribut() : return the attribut (also a tree) of t
- * \li t->attribut(t') : set the attribut of t to t'
- *
- *
- * <b>Properties:</b>
- *
- * If p and q are two CTree pointers :
- * p != q <=> *p != *q
- *
- **/
-
-/*****************************************************************************
-******************************************************************************/
-
-
-
-#ifndef __TREE__
-#define __TREE__
-
-#include "symbol.hh"
-#include "node.hh"
-#include <vector>
-#include <map>
-#include <assert.h>
-
-//---------------------------------API---------------------------------------
-
-class CTree;
-typedef CTree* Tree;
-
-typedef map<Tree, Tree> plist;
-typedef vector<Tree> tvec;
-
-/**
- * A CTree = (Node x [CTree]) is a Node associated with a list of subtrees called branches.
- * A CTree = (Node x [CTree]) is the association of a content Node and a list of subtrees
- * called branches. In order to maximize the sharing of trees, hashconsing techniques are used.
- * Ctrees at different addresses always have a different content. A first consequence of this
- * approach is that a fast equality test on pointers can be used as an equality test on CTrees.
- * A second consequence is that a CTree can NEVER be modified. But a property list is associated
- * to each CTree that can be used to attach arbitrary information to it. Due to the maximal
- * sharing property it is therefore easy to do memoization using these property lists.
- *
- * Means are also provided to do maximal sharing on recursive trees. The idea is to start from
- * a deBruijn representation and progressively build a classical representation such that
- * alpha-equivalent recursive CTrees are necesseraly identical (and therefore shared).
- *
- * WARNING : in the current implementation CTrees are allocated but never deleted
- **/
-
-class CTree
-{
- private:
- static const int kHashTableSize = 2000000; //510511; ///< size of the hash table used for "hash consing"
- static Tree gHashTable[kHashTableSize]; ///< hash table used for "hash consing"
-
- public:
- static bool gDetails; ///< Ctree::print() print with more details when true
- static unsigned int gVisitTime; ///< Should be incremented for each new visit to keep track of visited tree.
-
- private:
- // fields
- Tree fNext; ///< next tree in the same hashtable entry
- Node fNode; ///< the node content of the tree
- void* fType; ///< the type of a tree
- plist fProperties; ///< the properties list attached to the tree
- unsigned int fHashKey; ///< the hashtable key
- int fAperture; ///< how "open" is a tree (synthezised field)
- unsigned int fVisitTime; ///< keep track of visits
- tvec fBranch; ///< the subtrees
-
- CTree (unsigned int hk, const Node& n, const tvec& br); ///< construction is private, uses tree::make instead
-
- bool equiv (const Node& n, const tvec& br) const; ///< used to check if an equivalent tree already exists
- static unsigned int calcTreeHash (const Node& n, const tvec& br); ///< compute the hash key of a tree according to its node and branches
- static int calcTreeAperture (const Node& n, const tvec& br); ///< compute how open is a tree
-
- public:
- ~CTree ();
-
- static Tree make (const Node& n, int ar, Tree br[]); ///< return a new tree or an existing equivalent one
- static Tree make(const Node& n, const tvec& br); ///< return a new tree or an existing equivalent one
-
- // Accessors
- const Node& node() const { return fNode; } ///< return the content of the tree
- int arity() const { return fBranch.size();} ///< return the number of branches (subtrees) of a tree
- Tree branch(int i) const { return fBranch[i]; } ///< return the ith branch (subtree) of a tree
- unsigned int hashkey() const { return fHashKey; } ///< return the hashkey of the tree
- int aperture() const { return fAperture; } ///< return how "open" is a tree in terms of free variables
- void setAperture(int a) { fAperture=a; } ///< modify the aperture of a tree
-
-
- // Print a tree and the hash table (for debugging purposes)
- ostream& print (ostream& fout) const; ///< print recursively the content of a tree on a stream
- static void control (); ///< print the hash table content (for debug purpose)
-
- // type information
- void setType(void* t) { fType = t; }
- void* getType() { return fType; }
-
- // Keep track of visited trees (WARNING : non reentrant)
- static void startNewVisit() { ++gVisitTime; }
- bool isAlreadyVisited() { return fVisitTime==gVisitTime; }
- void setVisited() { /*assert(fVisitTime!=gVisitTime);*/ fVisitTime=gVisitTime; }
-
-
- // Property list of a tree
- void setProperty(Tree key, Tree value) { fProperties[key] = value; }
- void clearProperty(Tree key) { fProperties.erase(key); }
- void clearProperties() { fProperties = plist(); }
-
- void exportProperties(vector<Tree>& keys, vector<Tree>& values);
-
- Tree getProperty(Tree key) {
- plist::iterator i = fProperties.find(key);
- if (i==fProperties.end()) {
- return 0;
- } else {
- return i->second;
- }
- }
-};
-
-//---------------------------------API---------------------------------------
-
-// to build trees
-inline Tree tree (const Node& n) { Tree br[1]; return CTree::make(n, 0, br); }
-inline Tree tree (const Node& n, const Tree& a) { Tree br[]= {a}; return CTree::make(n, 1, br); }
-inline Tree tree (const Node& n, const Tree& a, const Tree& b) { Tree br[]= {a,b}; return CTree::make(n, 2, br); }
-inline Tree tree (const Node& n, const Tree& a, const Tree& b, const Tree& c) { Tree br[]= {a,b,c}; return CTree::make(n, 3, br); }
-inline Tree tree (const Node& n, const Tree& a, const Tree& b, const Tree& c, const Tree& d) { Tree br[]= {a,b,c,d}; return CTree::make(n, 4, br); }
-
-inline Tree tree (const Node& n, const Tree& a, const Tree& b, const Tree& c, const Tree& d, const Tree& e) { Tree br[]= {a,b,c,d,e}; return CTree::make(n, 5, br); }
-
-// useful conversions
-int tree2int (Tree t); ///< if t has a node of type int, return it otherwise error
-double tree2float (Tree t); ///< if t has a node of type float, return it otherwise error
-double tree2double (Tree t); ///< if t has a node of type float, return it otherwise error
-const char* tree2str (Tree t); ///< if t has a node of type symbol, return its name otherwise error
-void* tree2ptr (Tree t); ///< if t has a node of type ptr, return it otherwise error
-void* getUserData(Tree t); ///< if t has a node of type symbol, return the associated user data
-
-// pattern matching
-bool isTree (const Tree& t, const Node& n);
-bool isTree (const Tree& t, const Node& n, Tree& a);
-bool isTree (const Tree& t, const Node& n, Tree& a, Tree& b);
-bool isTree (const Tree& t, const Node& n, Tree& a, Tree& b, Tree& c);
-bool isTree (const Tree& t, const Node& n, Tree& a, Tree& b, Tree& c, Tree& d);
-bool isTree (const Tree& t, const Node& n, Tree& a, Tree& b, Tree& c, Tree& d, Tree& e);
-
-//printing
-inline ostream& operator << (ostream& s, const CTree& t) { return t.print(s); }
-
-
-//-----------------------------------------------------------------------------
-// recursive trees
-//-----------------------------------------------------------------------------
-
-// creation a recursive trees
-
-Tree rec(Tree body); ///< create a de Bruijn recursive tree
-Tree rec(Tree id, Tree body); ///< create a symbolic recursive tree
-
-bool isRec(Tree t, Tree& body); ///< is t a de Bruijn recursive tree
-bool isRec(Tree t, Tree& id, Tree& body); ///< is t a symbolic recursive tree
-
-// creation of recursive references
-
-Tree ref(int level); ///< create a de Bruijn recursive reference
-Tree ref(Tree id); ///< create a symbolic recursive reference
-
-bool isRef(Tree t, int& level); ///< is t a de Bruijn recursive reference
-bool isRef(Tree t, Tree& id); ///< is t a symbolic recursive reference
-
-
-// Open vs Closed regarding de Bruijn references
-
-inline bool isOpen(Tree t) { return t->aperture() > 0; } ///< t contains free de Bruijn references
-inline bool isClosed(Tree t) { return t->aperture() <= 0;} ///< t dont contain free de Bruijn ref
-
-// lift by 1 the free de Bruijn references
-
-Tree lift(Tree t); ////< add 1 to the free de bruijn references of t
-
-Tree deBruijn2Sym (Tree t); ////< transform a tree from deBruijn to symbolic notation
-void updateAperture (Tree t); ////< update aperture field of a tree in symbolic notation
-
-//---------------------------------------------------------------------------
-
-class Tabber
-{
- int fIndent;
- int fPostInc;
- public:
- Tabber(int n=0) : fIndent(n), fPostInc(0) {}
- Tabber& operator++() { fPostInc++; return *this;}
- Tabber& operator--() { assert(fIndent > 0); fIndent--; return *this; }
-
- ostream& print (ostream& fout)
- { for (int i=0; i<fIndent; i++) fout << '\t'; fIndent+=fPostInc; fPostInc=0; return fout; }
-};
-
-//printing
-inline ostream& operator << (ostream& s, Tabber& t) { return t.print(s); }
-
-extern Tabber TABBER;
-
-
-#endif