9f19ed7ed41ce53befeb9b51a25e19ca28b10b5b
[Faustine.git] / interpretor / preprocessor / faust-0.9.47mr3 / compiler / tlib / shlysis.cpp
1 /************************************************************************
2 ************************************************************************
3 FAUST compiler
4 Copyright (C) 2003-2004 GRAME, Centre National de Creation Musicale
5 ---------------------------------------------------------------------
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
10
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19 ************************************************************************
20 ************************************************************************/
21
22
23
24 /*****************************************************************************
25 ******************************************************************************
26 Tree Sharing Analysis
27 Y. Orlarey, (c) Grame 2002
28 ------------------------------------------------------------------------------
29 The sharing analysis of tree t is the annotation of all its subtrees t'
30 with their number of occurences in t. As this annotation of t' depends of
31 a context (the tree t for which t' is a subtree) a specific property key
32 unique to each sharing analysis must be generated.
33
34 API:
35 ----
36
37 shprkey(t) -> k = unique sharing property key of t
38 shcount(k,t') -> n = returns the number of occurences of t' in t (where k = shprkey(t))
39 shlysis(t) -> k = annotated the subtrees of t with prop (key sharing-count)
40 (0 if t' is not a subtree of t)
41
42 History :
43 ---------
44 2002-04-08 : First version
45 2006-03-25 : Modifications for new symbolic rec trees
46
47 ******************************************************************************
48 *****************************************************************************/
49
50 /**
51 * @file shlysis.cpp
52 * The sharing analysis of tree t is the annotation of all its subtrees t'
53 * with their number of occurences in t. As this annotation of t' depends of
54 * a context (the tree t for which t' is a subtree) a specific property key
55 * unique to each sharing analysis must be generated.
56 */
57
58 #include <string.h>
59 #include <stdlib.h>
60 #include <stdio.h>
61
62 #include "shlysis.hh"
63 #include "compatibility.hh"
64
65 /**
66 * Create a specific property key for the sharing count of subtrees of t
67 */
68
69 Tree shprkey(Tree t)
70 {
71 char name[256];
72 snprintf(name, 256, "SHARED IN %p : ", (CTree*)t);
73 return tree(unique(name));
74 }
75
76
77 /**
78 * Return the value of sharing count or 0
79 */
80
81 int shcount(Tree key, Tree t)
82 {
83 Tree c;
84 if (getProperty(t, key, c)) {
85 return c->node().getInt();
86 } else {
87 return 0;
88 }
89 }
90
91
92
93 //------------------------------------------------------------------------------
94 // Create a specific property key for the sharing count of subtrees of t
95 //------------------------------------------------------------------------------
96
97 static void annotate(Tree k, Tree t, barrier foo);
98
99 static bool nobarrier (const Tree& t) { return false; }
100
101 /**
102 * Do a sharing analysis : annotates all the subtrees of t
103 * with there occurences
104 */
105 Tree shlysis(Tree t, barrier foo)
106 {
107 Tree k = shprkey(t);
108 annotate(k, t, foo);
109 return k;
110 }
111
112
113 /**
114 * Do a sharing analysis : annotates all the subtrees of t
115 * with there occurences
116 */
117 Tree shlysis(Tree t)
118 {
119 Tree k = shprkey(t);
120 annotate(k, t, nobarrier);
121 return k;
122 }
123
124
125 /**
126 * Recursively increment the occurences count
127 * of t and its subtrees
128 */
129 static void annotate(Tree k, Tree t, barrier foo)
130 {
131 cerr << "Annotate " << *t << endl;
132 int c = shcount(k,t);
133 if (c==0) {
134 // First visit
135 Tree var, body;
136 if (isRec(t, var, body)) {
137 // special case for recursive trees
138 setProperty(t, k, tree(1));
139 annotate(k, body, foo);
140 return;
141 } else {
142 int n = t->arity();
143 if (n>0 && ! foo(t)) {
144 for (int i=0; i<n; i++) annotate(k, t->branch(i), foo);
145 }
146 }
147 } else {
148 //printf(" annotate %p with %d\n", (CTree*)t, c+1);
149 }
150 setProperty(t, k, tree(c+1));
151 }