--- /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
projects / Faustine.git / blobdiff