annotate lwasm/expr.c @ 151:427e268e876b

renamed src to lwasm to better reflect its purpose
author lost
date Fri, 30 Jan 2009 04:01:55 +0000
parents src/expr.c@718998b673ee
children bf69160da467
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1 /*
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2 expr.c
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3 Copyright © 2008 William Astle
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4
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5 This file is part of LWASM.
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6
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7 LWASM is free software: you can redistribute it and/or modify it under the
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8 terms of the GNU General Public License as published by the Free Software
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9 Foundation, either version 3 of the License, or (at your option) any later
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10 version.
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11
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12 This program is distributed in the hope that it will be useful, but WITHOUT
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13 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
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15 more details.
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16
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17 You should have received a copy of the GNU General Public License along with
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18 this program. If not, see <http://www.gnu.org/licenses/>.
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19 */
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20
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21 /*
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22 This file contains the actual expression evaluator
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23 */
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24
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25 #define __expr_c_seen__
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26
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27 #include <ctype.h>
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28 #include <stdlib.h>
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29 #include <string.h>
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30
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31 #include "expr.h"
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32 #include "util.h"
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33 #include "lwasm.h"
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34
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35 lwasm_expr_stack_t *lwasm_expr_stack_create(void)
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36 {
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37 lwasm_expr_stack_t *s;
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38
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39 s = lwasm_alloc(sizeof(lwasm_expr_stack_t));
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40 s -> head = NULL;
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41 s -> tail = NULL;
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42 return s;
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43 }
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44
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45 void lwasm_expr_stack_free(lwasm_expr_stack_t *s)
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46 {
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47 while (s -> head)
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48 {
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49 s -> tail = s -> head;
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50 s -> head = s -> head -> next;
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51 lwasm_expr_term_free(s -> tail -> term);
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52 lwasm_free(s -> tail);
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53 }
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54 lwasm_free(s);
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55 }
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56
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57 void lwasm_expr_term_free(lwasm_expr_term_t *t)
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58 {
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59 if (t)
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60 {
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61 if (t -> term_type == LWASM_TERM_SYM)
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62 lwasm_free(t -> symbol);
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63 lwasm_free(t);
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64 }
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65 }
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66
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67 lwasm_expr_term_t *lwasm_expr_term_create_oper(int oper)
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68 {
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69 lwasm_expr_term_t *t;
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70
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71 debug_message(10, "Creating operator term: %d", oper);
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72
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73 t = lwasm_alloc(sizeof(lwasm_expr_term_t));
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74 t -> term_type = LWASM_TERM_OPER;
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75 t -> value = oper;
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76 return t;
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77 }
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78
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79 lwasm_expr_term_t *lwasm_expr_term_create_int(int val)
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80 {
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81 lwasm_expr_term_t *t;
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82 debug_message(10, "Creating integer term: %d", val);
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83
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84 t = lwasm_alloc(sizeof(lwasm_expr_term_t));
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85 t -> term_type = LWASM_TERM_INT;
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86 t -> value = val;
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87 return t;
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88 }
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89
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90 lwasm_expr_term_t *lwasm_expr_term_create_secbase(void)
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91 {
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92 lwasm_expr_term_t *t;
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93 debug_message(10, "Creating section base term");
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94
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95 t = lwasm_alloc(sizeof(lwasm_expr_term_t));
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96 t -> term_type = LWASM_TERM_SECBASE;
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97 return t;
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98 }
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99
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100 lwasm_expr_term_t *lwasm_expr_term_create_sym(char *sym)
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101 {
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102 lwasm_expr_term_t *t;
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103
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104 debug_message(10, "Creating symbol term: %s", sym);
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105
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106 t = lwasm_alloc(sizeof(lwasm_expr_term_t));
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107 t -> term_type = LWASM_TERM_SYM;
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108 t -> symbol = lwasm_strdup(sym);
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109 return t;
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110 }
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111
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112 lwasm_expr_term_t *lwasm_expr_term_dup(lwasm_expr_term_t *t)
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113 {
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114 switch (t -> term_type)
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115 {
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116 case LWASM_TERM_INT:
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117 return lwasm_expr_term_create_int(t -> value);
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118
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119 case LWASM_TERM_OPER:
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120 return lwasm_expr_term_create_oper(t -> value);
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121
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122 case LWASM_TERM_SYM:
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123 return lwasm_expr_term_create_sym(t -> symbol);
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124
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125 case LWASM_TERM_SECBASE:
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126 return lwasm_expr_term_create_secbase();
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127
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128 default:
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129 debug_message(0, "lwasm_expr_term_dup(): invalid term type %d", t -> term_type);
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130 exit(1);
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131 }
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132 // can't get here
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133 }
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134
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135 void lwasm_expr_stack_push(lwasm_expr_stack_t *s, lwasm_expr_term_t *t)
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136 {
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137 lwasm_expr_stack_node_t *n;
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138
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139 if (!s)
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140 {
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141 debug_message(0, "lwasm_expr_stack_push(): invalid stack pointer");
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142 exit(1);
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143 }
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144
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145 n = lwasm_alloc(sizeof(lwasm_expr_stack_node_t));
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146 n -> next = NULL;
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147 n -> prev = s -> tail;
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148 n -> term = lwasm_expr_term_dup(t);
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149
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150 if (s -> head)
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151 {
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152 s -> tail -> next = n;
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153 s -> tail = n;
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154 }
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155 else
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156 {
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157 s -> head = n;
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158 s -> tail = n;
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159 }
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160 }
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161
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162 lwasm_expr_term_t *lwasm_expr_stack_pop(lwasm_expr_stack_t *s)
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163 {
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164 lwasm_expr_term_t *t;
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165 lwasm_expr_stack_node_t *n;
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166
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167 if (!(s -> tail))
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168 return NULL;
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169
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170 n = s -> tail;
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171 s -> tail = n -> prev;
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172 if (!(n -> prev))
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173 {
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174 s -> head = NULL;
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175 }
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176
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177 t = n -> term;
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178 n -> term = NULL;
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179
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180 lwasm_free(n);
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181
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182 return t;
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183 }
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184
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185 // the following two functions are co-routines which actually parse
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186 // an infix expression onto the expression stack, each returns -1
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187 // if an error is encountered
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188
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189 /*
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190 parse a term and push it onto the stack
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191
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192 this function handles unary prefix operators (-, +, .not., .com.)
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parents: 17
diff changeset
193 as well as ()
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parents: 17
diff changeset
194 */
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parents: 17
diff changeset
195 int lwasm_expr_parse_term(lwasm_expr_stack_t *s, const char **p)
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parents: 17
diff changeset
196 {
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diff changeset
197 lwasm_expr_term_t *t;
39
efa19ec69df9 tweaked debugging system for expression handler
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parents: 37
diff changeset
198 debug_message(2, "Expression string %s", *p);
efa19ec69df9 tweaked debugging system for expression handler
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parents: 37
diff changeset
199
18
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parents: 17
diff changeset
200 eval_next:
61
73423b66e511 Fixed error with single char ascii constants
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parents: 47
diff changeset
201 if (!**p || isspace(**p) || **p == ')' || **p == ']')
73423b66e511 Fixed error with single char ascii constants
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parents: 47
diff changeset
202 return -1;
18
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
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203 if (**p == '(')
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parents: 17
diff changeset
204 {
39
efa19ec69df9 tweaked debugging system for expression handler
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parents: 37
diff changeset
205 debug_message(3, "Starting paren");
18
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parents: 17
diff changeset
206 (*p)++;
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parents: 17
diff changeset
207 lwasm_expr_parse_expr(s, p, 0);
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parents: 17
diff changeset
208 if (**p != ')')
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209 return -1;
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parents: 17
diff changeset
210 (*p)++;
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parents: 17
diff changeset
211 return 0;
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parents: 17
diff changeset
212 }
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parents: 17
diff changeset
213
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
214 if (**p == '+')
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parents: 17
diff changeset
215 {
39
efa19ec69df9 tweaked debugging system for expression handler
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parents: 37
diff changeset
216 debug_message(3, "Unary +");
18
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parents: 17
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217 (*p)++;
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parents: 17
diff changeset
218 goto eval_next;
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parents: 17
diff changeset
219 }
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parents: 17
diff changeset
220
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
221 if (**p == '-')
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parents: 17
diff changeset
222 {
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parents: 17
diff changeset
223 // parse expression following "-"
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parents: 17
diff changeset
224 (*p)++;
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parents: 17
diff changeset
225 if (lwasm_expr_parse_expr(s, p, 200) < 0)
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parents: 17
diff changeset
226 return -1;
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parents: 17
diff changeset
227 t = lwasm_expr_term_create_oper(LWASM_OPER_NEG);
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diff changeset
228 lwasm_expr_stack_push(s, t);
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parents: 17
diff changeset
229 lwasm_expr_term_free(t);
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parents: 17
diff changeset
230 return 0;
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
231 }
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parents: 17
diff changeset
232
23
ec0bf61a5502 Added ^ (bitwise complement)
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parents: 18
diff changeset
233 if (**p == '^')
ec0bf61a5502 Added ^ (bitwise complement)
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parents: 18
diff changeset
234 {
ec0bf61a5502 Added ^ (bitwise complement)
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parents: 18
diff changeset
235 // parse expression following "^"
ec0bf61a5502 Added ^ (bitwise complement)
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parents: 18
diff changeset
236 (*p)++;
ec0bf61a5502 Added ^ (bitwise complement)
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parents: 18
diff changeset
237 if (lwasm_expr_parse_expr(s, p, 200) < 0)
ec0bf61a5502 Added ^ (bitwise complement)
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parents: 18
diff changeset
238 return -1;
ec0bf61a5502 Added ^ (bitwise complement)
lost
parents: 18
diff changeset
239 t = lwasm_expr_term_create_oper(LWASM_OPER_COM);
ec0bf61a5502 Added ^ (bitwise complement)
lost
parents: 18
diff changeset
240 lwasm_expr_stack_push(s, t);
ec0bf61a5502 Added ^ (bitwise complement)
lost
parents: 18
diff changeset
241 lwasm_expr_term_free(t);
ec0bf61a5502 Added ^ (bitwise complement)
lost
parents: 18
diff changeset
242 return 0;
ec0bf61a5502 Added ^ (bitwise complement)
lost
parents: 18
diff changeset
243 }
ec0bf61a5502 Added ^ (bitwise complement)
lost
parents: 18
diff changeset
244
18
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
245 /*
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
246 we have an actual term here so evaluate it
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
247
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
248 it could be one of the following:
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
249
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
250 1. a decimal constant
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
251 2. a hexadecimal constant
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
252 3. an octal constant
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parents: 17
diff changeset
253 4. a binary constant
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parents: 17
diff changeset
254 5. a symbol reference
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parents: 17
diff changeset
255 6. the "current" instruction address (*)
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parents: 17
diff changeset
256 7. the "current" data address (.)
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
257 8. a "back reference" (<)
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
258 9. a "forward reference" (>)
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
259
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
260 items 6 through 9 are stored as symbol references
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
261
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
262 (a . followed by a . or a alpha char or number is a symbol)
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
263 */
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parents: 17
diff changeset
264 if (**p == '*'
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
265 || (
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
266 **p == '.'
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parents: 17
diff changeset
267 && (*p)[1] != '.'
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parents: 17
diff changeset
268 && !((*p)[1] >= 'A' && (*p)[1] <= 'Z')
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parents: 17
diff changeset
269 && !((*p)[1] >= 'a' && (*p)[1] <= 'z')
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
270 && !((*p)[1] >= '0' && (*p)[1] <= '9')
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parents: 17
diff changeset
271 )
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
272 || **p == '<'
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
273 || **p == '>')
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
274 {
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
275 char tstr[2];
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
276 tstr[0] = **p;
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
277 tstr[1] = '\0';
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
278 t = lwasm_expr_term_create_sym(tstr);
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
279 lwasm_expr_stack_push(s, t);
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
280 lwasm_expr_term_free(t);
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
281 (*p)++;
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
282 return 0;
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
283 }
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
284
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
285 /*
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
286 - a symbol will be a string of characters introduced by a letter, ".",
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
287 "_" but NOT a number
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
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288 - a decimal constant will consist of only digits, optionally prefixed
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
289 with "&"
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
290 - a binary constant will consist of only 0s and 1s either prefixed with %
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
291 or suffixed with "B"
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
292 - a hex constant will consist of 0-9A-F either prefixed with $ or
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
293 suffixed with "H"; a hex number starting with A-F must be prefixed
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
294 with $ or start with 0 and end with H
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
295 - an octal constant will consist of 0-7 either prefixed with @ or
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
296 suffixed with "O" or "Q"
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
297 - an ascii constant will be a single character prefixed with a '
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
298 - a double ascii constant will be two characters prefixed with a "
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
299
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
300 */
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
301 if (**p == '"')
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
302 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
303 // double ascii constant
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
304 int val;
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
305 (*p)++;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
306 if (!**p)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
307 return -1;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
308 if (!*((*p)+1))
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
309 return -1;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
310 val = **p << 8 | *((*p) + 1);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
311 (*p) += 2;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
312 t = lwasm_expr_term_create_int(val);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
313 lwasm_expr_stack_push(s, t);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
314 lwasm_expr_term_free(t);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
315 return 0;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
316 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
317 else if (**p == '\'')
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
318 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
319 // single ascii constant
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
320 int val;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
321 (*p)++;
61
73423b66e511 Fixed error with single char ascii constants
lost
parents: 47
diff changeset
322 debug_message(3, "Single ascii character constant '%c'", **p);
18
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
323 if (!**p)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
324 return -1;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
325 val = **p;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
326 (*p)++;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
327 t = lwasm_expr_term_create_int(val);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
328 lwasm_expr_stack_push(s, t);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
329 lwasm_expr_term_free(t);
61
73423b66e511 Fixed error with single char ascii constants
lost
parents: 47
diff changeset
330 return 0;
18
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
331 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
332 else if (**p == '&')
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
333 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
334 // decimal constant
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
335 int val = 0;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
336
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
337 (*p)++;
47
804d7465e0f9 Implemented ORG and fixed problems with constants using $, &, or @ to specify base
lost
parents: 44
diff changeset
338 while (**p && strchr("0123456789", **p))
18
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
339 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
340 val = val * 10 + (**p - '0');
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
341 (*p)++;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
342 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
343 t = lwasm_expr_term_create_int(val);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
344 lwasm_expr_stack_push(s, t);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
345 lwasm_expr_term_free(t);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
346 return 0;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
347 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
348 else if (**p == '%')
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
349 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
350 // binary constant
218aabbc3b1a First pass at expression evaluator complete
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parents: 17
diff changeset
351 int val = 0;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
352
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
353 (*p)++;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
354 while (**p == '0' || **p == '1')
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
355 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
356 val = val * 2 + (**p - '0');
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
357 (*p)++;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
358 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
359 t = lwasm_expr_term_create_int(val);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
360 lwasm_expr_stack_push(s, t);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
361 lwasm_expr_term_free(t);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
362 return 0;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
363 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
364 else if (**p == '$')
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
365 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
366 // hexadecimal constant
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
367 int val = 0, val2;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
368
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
369 (*p)++;
47
804d7465e0f9 Implemented ORG and fixed problems with constants using $, &, or @ to specify base
lost
parents: 44
diff changeset
370 debug_message(3, "Found prefix hex constant: %s", *p);
804d7465e0f9 Implemented ORG and fixed problems with constants using $, &, or @ to specify base
lost
parents: 44
diff changeset
371 while (**p && strchr("0123456789ABCDEFabcdef", **p))
18
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
372 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
373 val2 = toupper(**p) - '0';
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
374 if (val2 > 9)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
375 val2 -= 7;
47
804d7465e0f9 Implemented ORG and fixed problems with constants using $, &, or @ to specify base
lost
parents: 44
diff changeset
376 debug_message(3, "Got char: %c (%d)", **p, val2);
18
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
377 val = val * 16 + val2;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
378 (*p)++;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
379 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
380 t = lwasm_expr_term_create_int(val);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
381 lwasm_expr_stack_push(s, t);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
382 lwasm_expr_term_free(t);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
383 return 0;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
384 }
40
d2cee0c335e7 adjusted symbol rules to accept symbols starting with @ but not @<digit>
lost
parents: 39
diff changeset
385 // an @ followed by a digit is an octal number
d2cee0c335e7 adjusted symbol rules to accept symbols starting with @ but not @<digit>
lost
parents: 39
diff changeset
386 // but if it's followed by anything else, it is a symbol
d2cee0c335e7 adjusted symbol rules to accept symbols starting with @ but not @<digit>
lost
parents: 39
diff changeset
387 else if (**p == '@' && isdigit(*(*p + 1)))
18
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
388 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
389 // octal constant
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
390 int val = 0;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
391
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
392 (*p)++;
47
804d7465e0f9 Implemented ORG and fixed problems with constants using $, &, or @ to specify base
lost
parents: 44
diff changeset
393 while (**p && strchr("01234567", **p))
18
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
394 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
395 val = val * 8 + (**p - '0');
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
396 (*p)++;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
397 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
398 t = lwasm_expr_term_create_int(val);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
399 lwasm_expr_stack_push(s, t);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
400 lwasm_expr_term_free(t);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
401 return 0;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
402 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
403
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
404 // symbol or bare decimal or suffix identified constant here
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
405 // all numbers will start with a digit at this point
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
406 if (**p < '0' || **p > '9')
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
407 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
408 int l = 0;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
409 char *sb;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
410
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
411 // evaluate a symbol here
41
7eafdb3a8074 Fixed symbol parsing to prevent string overflow
lost
parents: 40
diff changeset
412 static const char *symchars = "_.$@?abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
7eafdb3a8074 Fixed symbol parsing to prevent string overflow
lost
parents: 40
diff changeset
413 while ((*p)[l] && strchr(symchars, (*p)[l]))
18
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
414 l++;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
415
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
416 if (l == 0)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
417 return -1;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
418
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
419 sb = lwasm_alloc(l + 1);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
420 sb[l] = '\0';
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
421 memcpy(sb, *p, l);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
422 t = lwasm_expr_term_create_sym(sb);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
423 lwasm_expr_stack_push(s, t);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
424 lwasm_expr_term_free(t);
41
7eafdb3a8074 Fixed symbol parsing to prevent string overflow
lost
parents: 40
diff changeset
425 (*p) += l;
7eafdb3a8074 Fixed symbol parsing to prevent string overflow
lost
parents: 40
diff changeset
426 debug_message(3, "Symbol: '%s'; (%s)", sb, *p);
18
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
427 lwasm_free(sb);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
428 return 0;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
429 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
430
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
431 if (!**p)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
432 return -1;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
433
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
434 // evaluate a suffix based constant
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
435 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
436 int decval = 0, binval = 0, hexval = 0, octval = 0;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
437 int valtype = 15; // 1 = bin, 2 = oct, 4 = dec, 8 = hex
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
438 int bindone = 0;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
439 int val;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
440 int dval;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
441
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
442 while (1)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
443 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
444 if (!**p || !strchr("0123456789ABCDEFabcdefqhoQHO", **p))
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
445 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
446 // we can legally have bin or decimal here
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
447 if (bindone)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
448 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
449 // we just finished a binary value
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
450 val = binval;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
451 break;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
452 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
453 else if (valtype & 4)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
454 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
455 // otherwise we must be decimal (if we're still allowed one)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
456 val = decval;
39
efa19ec69df9 tweaked debugging system for expression handler
lost
parents: 37
diff changeset
457 debug_message(3, "End of decimal value");
18
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
458 break;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
459 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
460 else
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
461 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
462 // bad value
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
463 return -1;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
464 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
465 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
466
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
467 dval = toupper(**p);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
468 (*p)++;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
469
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
470 if (bindone)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
471 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
472 // any characters past "B" means it is not binary
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
473 bindone = 0;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
474 valtype &= 14;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
475 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
476
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
477 switch (dval)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
478 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
479 case 'Q':
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
480 case 'O':
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
481 if (valtype & 2)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
482 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
483 val = octval;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
484 valtype = -1;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
485 break;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
486 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
487 else
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
488 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
489 // not a valid octal value
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
490 return -1;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
491 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
492 /* can't get here */
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
493
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
494 case 'H':
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
495 if (valtype & 8)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
496 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
497 val = hexval;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
498 valtype = -1;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
499 break;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
500 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
501 else
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
502 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
503 // not a valid hex number
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
504 return -1;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
505 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
506 /* can't get here */
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
507
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
508 case 'B':
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
509 // this is a bit of a sticky one since B is a legit hex
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
510 // digit so this may or may not be the end of the number
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
511 // so we fall through to the digit case
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
512
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
513 if (valtype & 1)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
514 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
515 // could still be binary
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
516 bindone = 1;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
517 valtype = 9; // hex and binary
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
518 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
519 /* fall through intentional */
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
520
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
521 default:
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
522 // digit
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
523 dval -= '0';
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
524 if (dval > 9)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
525 dval -= 7;
39
efa19ec69df9 tweaked debugging system for expression handler
lost
parents: 37
diff changeset
526 debug_message(3, "Got digit: %d", dval);
37
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
527 // if (dval > 1)
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
528 // valtype &= 14;
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
529 // if (dval > 7)
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
530 // valtype &= 12;
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
531 // if (dval > 9)
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
532 // valtype &= 8;
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
533
18
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
534 if (valtype & 8)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
535 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
536 hexval = hexval * 16 + dval;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
537 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
538 if (valtype & 4)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
539 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
540 if (dval > 9)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
541 valtype &= 11;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
542 else
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
543 decval = decval * 10 + dval;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
544 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
545 if (valtype & 2)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
546 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
547 if (dval > 7)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
548 valtype &= 13;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
549 else
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
550 octval = octval * 8 + dval;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
551 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
552 if (valtype & 1)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
553 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
554 if (dval > 1)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
555 valtype &= 14;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
556 else
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
557 binval = binval * 2 + dval;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
558 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
559 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
560 // break out if we have a return value
37
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
561 if (valtype == -1)
18
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
562 break;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
563 // return if no more valid possibilities!
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
564 if (valtype == 0)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
565 return -1;
37
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
566 val = decval; // in case we fall through
18
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
567 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
568
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
569 // we get here when we have a value to return
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
570 t = lwasm_expr_term_create_int(val);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
571 lwasm_expr_stack_push(s, t);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
572 lwasm_expr_term_free(t);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
573 return 0;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
574 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
575 /* can't get here */
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
576 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
577
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
578 // parse an expression and push the result onto the stack
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
579 // if an operator of lower precedence than the value of "prec" is found,
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
580 int lwasm_expr_parse_expr(lwasm_expr_stack_t *s, const char **p, int prec)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
581 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
582 static const struct operinfo
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
583 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
584 int opernum;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
585 char *operstr;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
586 int operprec;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
587 } operators[] =
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
588 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
589 { LWASM_OPER_PLUS, "+", 100 },
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
590 { LWASM_OPER_MINUS, "-", 100 },
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
591 { LWASM_OPER_TIMES, "*", 150 },
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
592 { LWASM_OPER_DIVIDE, "/", 150 },
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
593 { LWASM_OPER_MOD, "%", 150 },
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
594 { LWASM_OPER_INTDIV, "\\", 150 },
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
595
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
596 { LWASM_OPER_NONE, "", 0 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
597 };
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
598 int opern, i;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
599 lwasm_expr_term_t *operterm;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
600
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
601 // return if we are at the end of the expression or a subexpression
61
73423b66e511 Fixed error with single char ascii constants
lost
parents: 47
diff changeset
602 if (!**p || isspace(**p) || **p == ')' || **p == ',' || **p == ']')
18
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
603 return 0;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
604
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
605 if (lwasm_expr_parse_term(s, p) < 0)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
606 return -1;
37
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
607
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
608 eval_next:
61
73423b66e511 Fixed error with single char ascii constants
lost
parents: 47
diff changeset
609 if (!**p || isspace(**p) || **p == ')' || **p == ',' || **p == ']')
37
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
610 return 0;
18
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
611
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
612 // expecting an operator here
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
613 for (opern = 0; operators[opern].opernum != LWASM_OPER_NONE; opern++)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
614 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
615 for (i = 0; (*p)[i] && operators[opern].operstr[i] && (*p[i] == operators[opern].operstr[i]); i++)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
616 /* do nothing */ ;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
617 if (operators[opern].operstr[i] == '\0')
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
618 break;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
619 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
620 if (operators[opern].opernum == LWASM_OPER_NONE)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
621 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
622 // unrecognized operator
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
623 return -1;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
624 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
625
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
626 // the operator number in question is in opern; i is the length of the
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
627 // operator string
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
628
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
629 // logic:
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
630 // if the precedence of this operation is <= to the "prec" flag,
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
631 // we simply return without advancing the input pointer; the operator
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
632 // will be evaluated again in the enclosing function call
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
633 if (operators[opern].operprec <= prec)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
634 return 0;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
635
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
636 // logic:
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
637 // we have a higher precedence operator here so we will advance the
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
638 // input pointer to the next term and let the expression evaluator
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
639 // loose on it after which time we will push our operator onto the
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
640 // stack and then go on with the expression evaluation
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
641 (*p) += i; // advance input pointer
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
642
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
643 // evaluate next expression(s) of higher precedence
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
644 if (lwasm_expr_parse_expr(s, p, operators[opern].operprec) < 0)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
645 return -1;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
646
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
647 operterm = lwasm_expr_term_create_oper(operators[opern].opernum);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
648 lwasm_expr_stack_push(s, operterm);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
649 lwasm_expr_term_free(operterm);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
650
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
651 // return if we are at the end of the expression or a subexpression
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
652 if (!**p || isspace(**p) || **p == ')')
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
653 return 0;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
654
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
655 // continue evaluating
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
656 goto eval_next;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
657 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
658
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
659 /*
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
660 actually evaluate an expression
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
661
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
662 This happens in two stages. The first stage merely parses the expression into
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
663 a lwasm_expr_stack_t * which is then evaluated as much as possible before the
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
664 result is returned.
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
665
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
666 Returns NULL on a parse error or otherwise invalid expression. *outp will
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
667 contain the pointer to the next character after the expression if and only
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
668 if there is no error. In the case of an error, *outp is undefined.
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
669 */
76
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
670 lwasm_expr_stack_t *lwasm_expr_eval(const char *inp, const char **outp, lwasm_expr_stack_t *(*sfunc)(char *sym, void *state), void *state)
18
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
671 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
672 lwasm_expr_stack_t *s;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
673 const char *p;
37
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
674 int rval;
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
675
18
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
676 // actually parse the expression
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
677 p = inp;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
678 s = lwasm_expr_stack_create();
37
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
679
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
680 rval = lwasm_expr_parse_expr(s, &p, 0);
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
681 if (rval < 0)
18
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
682 goto cleanup_error;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
683
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
684 // save end of expression
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
685 if (outp)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
686 (*outp) = p;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
687
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
688 // return potentially partial expression
37
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
689 if (lwasm_expr_reval(s, sfunc, state) < 0)
18
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
690 goto cleanup_error;
37
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
691
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
692 if (lwasm_expr_is_constant(s))
39
efa19ec69df9 tweaked debugging system for expression handler
lost
parents: 37
diff changeset
693 debug_message(3, "Constant expression evaluates to: %d", lwasm_expr_get_value(s));
18
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
694
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
695 return s;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
696
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
697 cleanup_error:
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
698 lwasm_expr_stack_free(s);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
699 return NULL;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
700 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
701
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
702 /*
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
703 take an expression stack s and scan for operations that can be completed
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
704
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
705 return -1 on error, 0 on no error
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
706
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
707 possible errors are: division by zero or unknown operator
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
708
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
709 theory of operation:
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
710
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
711 scan the stack for an operator which has two constants preceding it (binary)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
712 or 1 constant preceding it (unary) and if found, perform the calculation
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
713 and replace the operator and its operands with the result
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
714
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
715 repeat the scan until no futher simplications are found or if there are no
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
716 further operators or only a single term remains
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
717
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
718 */
76
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
719 int lwasm_expr_reval(lwasm_expr_stack_t *s, lwasm_expr_stack_t *(*sfunc)(char *sym, void *state), void *state)
18
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
720 {
76
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
721 lwasm_expr_stack_node_t *n, *n2;
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
722 lwasm_expr_stack_t *ss;
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
723 int c;
37
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
724
76
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
725 next_iter_sym:
37
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
726 // resolve symbols
76
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
727 // symbols that do not resolve to an expression are left alone
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
728 for (c = 0, n = s -> head; n; n = n -> next)
37
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
729 {
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
730 if (n -> term -> term_type == LWASM_TERM_SYM)
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
731 {
76
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
732 ss = sfunc(n -> term -> symbol, state);
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
733 if (ss)
37
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
734 {
76
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
735 c++;
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
736 // splice in the result stack
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
737 if (n -> prev)
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
738 {
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
739 n -> prev -> next = ss -> head;
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
740 }
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
741 else
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
742 {
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
743 s -> head = ss -> head;
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
744 }
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
745 ss -> head -> prev = n -> prev;
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
746 ss -> tail -> next = n -> next;
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
747 if (n -> next)
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
748 {
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
749 n -> next -> prev = ss -> tail;
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
750 }
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
751 else
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
752 {
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
753 s -> tail = ss -> tail;
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
754 }
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
755 lwasm_expr_term_free(n -> term);
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
756 lwasm_free(n);
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
757 n = ss -> tail;
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
758
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
759 ss -> head = NULL;
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
760 ss -> tail = NULL;
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
761 lwasm_expr_stack_free(ss);
37
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
762 }
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
763 }
538e15927776 Added symbol handling to expression subsystem; adpated instruction handlers to the new scheme; misc fixes
lost
parents: 23
diff changeset
764 }
76
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
765 if (c)
2fe5fd7d65a3 Checkpointing object target implementation
lost
parents: 61
diff changeset
766 goto next_iter_sym;
18
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
767
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
768 next_iter:
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
769 // a single term
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
770 if (s -> head == s -> tail)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
771 return 0;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
772
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
773 // search for an operator
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
774 for (n = s -> head; n; n = n -> next)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
775 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
776 if (n -> term -> term_type == LWASM_TERM_OPER)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
777 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
778 if (n -> term -> value == LWASM_OPER_NEG
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
779 || n -> term -> value == LWASM_OPER_COM
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
780 )
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
781 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
782 // unary operator
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
783 if (n -> prev && n -> prev -> term -> term_type == LWASM_TERM_INT)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
784 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
785 // a unary operator we can resolve
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
786 // we do the op then remove the term "n" is pointing at
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
787 if (n -> term -> value == LWASM_OPER_NEG)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
788 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
789 n -> prev -> term -> value = -(n -> prev -> term -> value);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
790 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
791 else if (n -> term -> value == LWASM_OPER_COM)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
792 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
793 n -> prev -> term -> value = ~(n -> prev -> term -> value);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
794 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
795 n -> prev -> next = n -> next;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
796 if (n -> next)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
797 n -> next -> prev = n -> prev;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
798 else
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
799 s -> tail = n -> prev;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
800
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
801 lwasm_expr_term_free(n -> term);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
802 lwasm_free(n);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
803 break;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
804 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
805 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
806 else
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
807 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
808 // binary operator
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
809 if (n -> prev && n -> prev -> prev && n -> prev -> term -> term_type == LWASM_TERM_INT && n -> prev -> prev -> term -> term_type == LWASM_TERM_INT)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
810 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
811 // a binary operator we can resolve
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
812 switch (n -> term -> value)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
813 {
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
814 case LWASM_OPER_PLUS:
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
815 n -> prev -> prev -> term -> value += n -> prev -> term -> value;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
816 break;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
817
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
818 case LWASM_OPER_MINUS:
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
819 n -> prev -> prev -> term -> value -= n -> prev -> term -> value;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
820 break;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
821
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
822 case LWASM_OPER_TIMES:
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
823 n -> prev -> prev -> term -> value *= n -> prev -> term -> value;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
824 break;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
825
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
826 case LWASM_OPER_DIVIDE:
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
827 if (n -> prev -> term -> value == 0)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
828 return -1;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
829 n -> prev -> prev -> term -> value /= n -> prev -> term -> value;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
830 break;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
831
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
832 case LWASM_OPER_MOD:
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
833 if (n -> prev -> term -> value == 0)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
834 return -1;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
835 n -> prev -> prev -> term -> value %= n -> prev -> term -> value;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
836 break;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
837
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
838 case LWASM_OPER_INTDIV:
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
839 if (n -> prev -> term -> value == 0)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
840 return -1;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
841 n -> prev -> prev -> term -> value /= n -> prev -> term -> value;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
842 break;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
843
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
844 case LWASM_OPER_BWAND:
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
845 n -> prev -> prev -> term -> value &= n -> prev -> term -> value;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
846 break;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
847
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
848 case LWASM_OPER_BWOR:
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
849 n -> prev -> prev -> term -> value |= n -> prev -> term -> value;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
850 break;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
851
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
852 case LWASM_OPER_BWXOR:
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
853 n -> prev -> prev -> term -> value ^= n -> prev -> term -> value;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
854 break;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
855
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
856 case LWASM_OPER_AND:
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
857 n -> prev -> prev -> term -> value = (n -> prev -> term -> value && n -> prev -> prev -> term -> value) ? 1 : 0;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
858 break;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
859
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
860 case LWASM_OPER_OR:
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
861 n -> prev -> prev -> term -> value = (n -> prev -> term -> value || n -> prev -> prev -> term -> value) ? 1 : 0;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
862 break;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
863
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
864 default:
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
865 // return error if unknown operator!
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
866 return -1;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
867 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
868
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
869 // now remove the two unneeded entries from the stack
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
870 n -> prev -> prev -> next = n -> next;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
871 if (n -> next)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
872 n -> next -> prev = n -> prev -> prev;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
873 else
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
874 s -> tail = n -> prev -> prev;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
875
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
876 lwasm_expr_term_free(n -> term);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
877 lwasm_expr_term_free(n -> prev -> term);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
878 lwasm_free(n -> prev);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
879 lwasm_free(n);
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
880 break;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
881 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
882 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
883 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
884 }
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
885 // note for the terminally confused about dynamic memory and pointers:
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
886 // n will not be NULL even after the lwasm_free calls above so
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
887 // this test will still work (n will be a dangling pointer)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
888 // (n will only be NULL if we didn't find any operators to simplify)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
889 if (n)
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
890 goto next_iter;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
891
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
892 return 0;
218aabbc3b1a First pass at expression evaluator complete
lost
parents: 17
diff changeset
893 }