1/*
2 * Copyright (c) 2016 ARM Limited
3 * All rights reserved
4 *
5 * The license below extends only to copyright in the software and shall
6 * not be construed as granting a license to any other intellectual
7 * property including but not limited to intellectual property relating
8 * to a hardware implementation of the functionality of the software
9 * licensed hereunder. You may use the software subject to the license
10 * terms below provided that you ensure that this notice is replicated
11 * unmodified and in its entirety in all distributions of the software,
12 * modified or unmodified, in source code or in binary form.
13 *
14 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions are
16 * met: redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer;
18 * redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution;
21 * neither the name of the copyright holders nor the names of its
22 * contributors may be used to endorse or promote products derived from
23 * this software without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
26 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
27 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
28 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
29 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
30 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
31 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
32 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
35 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36 *
37 * Authors: David Guillen Fandos
38 */
39
40#include "sim/mathexpr.hh"
41
42#include <algorithm>
43#include <cmath>
44#include <regex>
45#include <string>
46
| 1/*
2 * Copyright (c) 2016 ARM Limited
3 * All rights reserved
4 *
5 * The license below extends only to copyright in the software and shall
6 * not be construed as granting a license to any other intellectual
7 * property including but not limited to intellectual property relating
8 * to a hardware implementation of the functionality of the software
9 * licensed hereunder. You may use the software subject to the license
10 * terms below provided that you ensure that this notice is replicated
11 * unmodified and in its entirety in all distributions of the software,
12 * modified or unmodified, in source code or in binary form.
13 *
14 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions are
16 * met: redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer;
18 * redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution;
21 * neither the name of the copyright holders nor the names of its
22 * contributors may be used to endorse or promote products derived from
23 * this software without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
26 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
27 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
28 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
29 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
30 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
31 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
32 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
35 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36 *
37 * Authors: David Guillen Fandos
38 */
39
40#include "sim/mathexpr.hh"
41
42#include <algorithm>
43#include <cmath>
44#include <regex>
45#include <string>
46
|
48
49MathExpr::MathExpr(std::string expr)
50 : ops(
51 std::array<OpSearch, uNeg + 1> {{
52 OpSearch {true, bAdd, 0, '+', [](double a, double b) { return a + b; }},
53 OpSearch {true, bSub, 0, '-', [](double a, double b) { return a - b; }},
54 OpSearch {true, bMul, 1, '*', [](double a, double b) { return a * b; }},
55 OpSearch {true, bDiv, 1, '/', [](double a, double b) { return a / b; }},
56 OpSearch {false,uNeg, 2, '-', [](double a, double b) { return -b; }},
57 OpSearch {true, bPow, 3, '^', [](double a, double b) {
58 return std::pow(a,b); }
59 }},
60 })
61{
62 // Cleanup
63 expr.erase(remove_if(expr.begin(), expr.end(), isspace), expr.end());
64
65 root = MathExpr::parse(expr);
66 panic_if(!root, "Invalid expression\n");
67}
68
69/**
70 * This function parses a string expression into an expression tree.
71 * It will look for operators in priority order to recursively build the
72 * tree, respecting parenthesization.
73 * Constants can be expressed in any format accepted by std::stod, whereas
74 * variables are essentially [A-Za-z0-9\.$\\]+
75 */
76MathExpr::Node *
77MathExpr::parse(std::string expr) {
78 if (expr.size() == 0)
79 return NULL;
80
81 // From low to high priority
82 int par = 0;
83 for (unsigned p = 0; p < MAX_PRIO; p++) {
84 for (int i = expr.size() - 1; i >= 0; i--) {
85 if (expr[i] == ')')
86 par++;
87 if (expr[i] == '(')
88 par--;
89
90 if (par < 0) return NULL;
91 if (par > 0) continue;
92
93 for (unsigned opt = 0; opt < ops.size(); opt++) {
94 if (ops[opt].priority != p) continue;
95 if (ops[opt].c == expr[i]) {
96 // Try to parse each side
97 Node *l = NULL;
98 if (ops[opt].binary)
99 l = parse(expr.substr(0, i));
100 Node *r = parse(expr.substr(i + 1));
101 if ((l && r) || (!ops[opt].binary && r)) {
102 // Match!
103 Node *n = new Node();
104 n->op = ops[opt].op;
105 n->l = l;
106 n->r = r;
107 return n;
108 }
109 }
110 }
111 }
112 }
113
114 // Remove trivial parenthesis
115 if (expr.size() >= 2 && expr[0] == '(' && expr[expr.size() - 1] == ')')
116 return parse(expr.substr(1, expr.size() - 2));
117
118 // Match a number
119 {
120 char *sptr;
121 double v = strtod(expr.c_str(), &sptr);
122 if (sptr != expr.c_str()) {
123 Node *n = new Node();
124 n->op = sValue;
125 n->value = v;
126 return n;
127 }
128 }
129
130 // Match a variable
131 {
132 bool contains_non_alpha = false;
133 for (auto & c: expr)
134 contains_non_alpha = contains_non_alpha or
135 !( (c >= 'a' && c <= 'z') ||
136 (c >= 'A' && c <= 'Z') ||
137 (c >= '0' && c <= '9') ||
138 c == '$' || c == '\\' || c == '.' || c == '_');
139
140 if (!contains_non_alpha) {
141 Node * n = new Node();
142 n->op = sVariable;
143 n->variable = expr;
144 return n;
145 }
146 }
147
148 return NULL;
149}
150
151double
152MathExpr::eval(const Node *n, EvalCallback fn) const {
153 if (!n)
154 return 0;
155 else if (n->op == sValue)
156 return n->value;
157 else if (n->op == sVariable)
158 return fn(n->variable);
159
160 for (auto & opt : ops)
161 if (opt.op == n->op)
162 return opt.fn( eval(n->l, fn), eval(n->r, fn) );
163
164 panic("Invalid node!\n");
165 return 0;
166}
167
168std::string
169MathExpr::toStr(Node *n, std::string prefix) const {
170 std::string ret;
171 ret += prefix + "|-- " + n->toStr() + "\n";
172 if (n->r)
173 ret += toStr(n->r, prefix + "| ");
174 if (n->l)
175 ret += toStr(n->l, prefix + "| ");
176 return ret;
177}
178
| 48
49MathExpr::MathExpr(std::string expr)
50 : ops(
51 std::array<OpSearch, uNeg + 1> {{
52 OpSearch {true, bAdd, 0, '+', [](double a, double b) { return a + b; }},
53 OpSearch {true, bSub, 0, '-', [](double a, double b) { return a - b; }},
54 OpSearch {true, bMul, 1, '*', [](double a, double b) { return a * b; }},
55 OpSearch {true, bDiv, 1, '/', [](double a, double b) { return a / b; }},
56 OpSearch {false,uNeg, 2, '-', [](double a, double b) { return -b; }},
57 OpSearch {true, bPow, 3, '^', [](double a, double b) {
58 return std::pow(a,b); }
59 }},
60 })
61{
62 // Cleanup
63 expr.erase(remove_if(expr.begin(), expr.end(), isspace), expr.end());
64
65 root = MathExpr::parse(expr);
66 panic_if(!root, "Invalid expression\n");
67}
68
69/**
70 * This function parses a string expression into an expression tree.
71 * It will look for operators in priority order to recursively build the
72 * tree, respecting parenthesization.
73 * Constants can be expressed in any format accepted by std::stod, whereas
74 * variables are essentially [A-Za-z0-9\.$\\]+
75 */
76MathExpr::Node *
77MathExpr::parse(std::string expr) {
78 if (expr.size() == 0)
79 return NULL;
80
81 // From low to high priority
82 int par = 0;
83 for (unsigned p = 0; p < MAX_PRIO; p++) {
84 for (int i = expr.size() - 1; i >= 0; i--) {
85 if (expr[i] == ')')
86 par++;
87 if (expr[i] == '(')
88 par--;
89
90 if (par < 0) return NULL;
91 if (par > 0) continue;
92
93 for (unsigned opt = 0; opt < ops.size(); opt++) {
94 if (ops[opt].priority != p) continue;
95 if (ops[opt].c == expr[i]) {
96 // Try to parse each side
97 Node *l = NULL;
98 if (ops[opt].binary)
99 l = parse(expr.substr(0, i));
100 Node *r = parse(expr.substr(i + 1));
101 if ((l && r) || (!ops[opt].binary && r)) {
102 // Match!
103 Node *n = new Node();
104 n->op = ops[opt].op;
105 n->l = l;
106 n->r = r;
107 return n;
108 }
109 }
110 }
111 }
112 }
113
114 // Remove trivial parenthesis
115 if (expr.size() >= 2 && expr[0] == '(' && expr[expr.size() - 1] == ')')
116 return parse(expr.substr(1, expr.size() - 2));
117
118 // Match a number
119 {
120 char *sptr;
121 double v = strtod(expr.c_str(), &sptr);
122 if (sptr != expr.c_str()) {
123 Node *n = new Node();
124 n->op = sValue;
125 n->value = v;
126 return n;
127 }
128 }
129
130 // Match a variable
131 {
132 bool contains_non_alpha = false;
133 for (auto & c: expr)
134 contains_non_alpha = contains_non_alpha or
135 !( (c >= 'a' && c <= 'z') ||
136 (c >= 'A' && c <= 'Z') ||
137 (c >= '0' && c <= '9') ||
138 c == '$' || c == '\\' || c == '.' || c == '_');
139
140 if (!contains_non_alpha) {
141 Node * n = new Node();
142 n->op = sVariable;
143 n->variable = expr;
144 return n;
145 }
146 }
147
148 return NULL;
149}
150
151double
152MathExpr::eval(const Node *n, EvalCallback fn) const {
153 if (!n)
154 return 0;
155 else if (n->op == sValue)
156 return n->value;
157 else if (n->op == sVariable)
158 return fn(n->variable);
159
160 for (auto & opt : ops)
161 if (opt.op == n->op)
162 return opt.fn( eval(n->l, fn), eval(n->r, fn) );
163
164 panic("Invalid node!\n");
165 return 0;
166}
167
168std::string
169MathExpr::toStr(Node *n, std::string prefix) const {
170 std::string ret;
171 ret += prefix + "|-- " + n->toStr() + "\n";
172 if (n->r)
173 ret += toStr(n->r, prefix + "| ");
174 if (n->l)
175 ret += toStr(n->l, prefix + "| ");
176 return ret;
177}
178
|