Mercurial > hg > index.cgi
annotate lwcc/cc-parse.c @ 501:f3e9732973f1
Add basic integer operations to lwcc
Add +, -, *, and / to lwcc parser and code generator. Multiplication and
division require helper functions in a yet to be created support library.
These operations are integer only for the moment.
| author | William Astle <lost@l-w.ca> |
|---|---|
| date | Tue, 24 Sep 2019 22:07:56 -0600 |
| parents | 1bd2d590d734 |
| children | 14a40f8bb4eb |
| rev | line source |
|---|---|
| 498 | 1 /* |
| 2 lwcc/cc-parse.c | |
| 3 | |
| 4 Copyright © 2019 William Astle | |
| 5 | |
| 6 This file is part of LWTOOLS. | |
| 7 | |
| 8 LWTOOLS is free software: you can redistribute it and/or modify it under the | |
| 9 terms of the GNU General Public License as published by the Free Software | |
| 10 Foundation, either version 3 of the License, or (at your option) any later | |
| 11 version. | |
| 12 | |
| 13 This program is distributed in the hope that it will be useful, but WITHOUT | |
| 14 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
| 15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
| 16 more details. | |
| 17 | |
| 18 You should have received a copy of the GNU General Public License along with | |
| 19 this program. If not, see <http://www.gnu.org/licenses/>. | |
| 20 */ | |
| 21 | |
| 22 #include <string.h> | |
| 23 | |
| 24 #include <lw_alloc.h> | |
| 25 #include <lw_string.h> | |
| 26 | |
| 27 #include "cpp.h" | |
| 28 #include "tree.h" | |
| 29 | |
| 30 #define TOK_KW_IF -1 | |
| 31 #define TOK_KW_ELSE -2 | |
| 32 #define TOK_KW_WHILE -3 | |
| 33 #define TOK_KW_DO -4 | |
| 34 #define TOK_KW_FOR -5 | |
| 35 #define TOK_KW_VOID -6 | |
| 36 #define TOK_KW_INT -7 | |
| 37 #define TOK_KW_CHAR -8 | |
| 38 #define TOK_KW_SHORT -9 | |
| 39 #define TOK_KW_LONG -10 | |
| 40 #define TOK_KW_UNSIGNED -11 | |
| 41 #define TOK_KW_SIGNED -12 | |
| 42 #define TOK_KW_FLOAT -13 | |
| 43 #define TOK_KW_DOUBLE -14 | |
| 44 #define TOK_KW_STRUCT -15 | |
| 45 #define TOK_KW_UNION -16 | |
| 46 #define TOK_KW_TYPEDEF -17 | |
| 47 #define TOK_KW_STATIC -18 | |
| 48 #define TOK_KW_SWITCH -19 | |
| 49 #define TOK_KW_CASE -20 | |
| 50 #define TOK_KW_DEFAULT -21 | |
| 51 #define TOK_KW_BREAK -22 | |
| 52 #define TOK_KW_CONTINUE -23 | |
| 53 #define TOK_KW_CONST -24 | |
| 54 #define TOK_KW_AUTO -25 | |
| 55 #define TOK_KW_ENUM -26 | |
| 56 #define TOK_KW_REGISTER -27 | |
| 57 #define TOK_KW_SIZEOF -28 | |
| 58 #define TOK_KW_VOLATILE -29 | |
| 59 #define TOK_KW_RETURN -30 | |
| 60 #define TOK_KW_EXTERN -31 | |
| 61 #define TOK_KW_GOTO -32 | |
| 62 #define TOK_TYPENAME -100 | |
| 63 #define TOK_CONST_INT -150 | |
| 64 | |
| 65 static struct { int tok; char *word; } keyword_list[] = { | |
| 66 { TOK_KW_IF, "if" }, | |
| 67 { TOK_KW_ELSE, "else" }, | |
| 68 { TOK_KW_WHILE, "while" }, | |
| 69 { TOK_KW_DO, "do" }, | |
| 70 { TOK_KW_FOR, "for" }, | |
| 71 { TOK_KW_VOID, "void" }, | |
| 72 { TOK_KW_INT, "int" }, | |
| 73 { TOK_KW_CHAR, "char" }, | |
| 74 { TOK_KW_SHORT, "short" }, | |
| 75 { TOK_KW_LONG, "long" }, | |
| 76 { TOK_KW_UNSIGNED, "unsigned" }, | |
| 77 { TOK_KW_SIGNED, "signed" }, | |
| 78 { TOK_KW_FLOAT, "float" }, | |
| 79 { TOK_KW_DOUBLE, "double" }, | |
| 80 { TOK_KW_STRUCT, "struct" }, | |
| 81 { TOK_KW_UNION, "union" }, | |
| 82 { TOK_KW_TYPEDEF, "typedef" }, | |
| 83 { TOK_KW_STATIC, "static" }, | |
| 84 { TOK_KW_SWITCH, "switch" }, | |
| 85 { TOK_KW_CASE, "case" }, | |
| 86 { TOK_KW_DEFAULT, "default" }, | |
| 87 { TOK_KW_BREAK, "break" }, | |
| 88 { TOK_KW_CONTINUE, "continue" }, | |
| 89 { TOK_KW_CONST, "const" }, | |
| 90 { TOK_KW_AUTO, "auto" }, | |
| 91 { TOK_KW_ENUM, "enum" }, | |
| 92 { TOK_KW_REGISTER, "register" }, | |
| 93 { TOK_KW_SIZEOF, "sizeof" }, | |
| 94 { TOK_KW_VOLATILE, "volatile" }, | |
| 95 { TOK_KW_RETURN, "return" }, | |
| 96 { TOK_KW_EXTERN, "extern" }, | |
| 97 { TOK_KW_GOTO, "goto" }, | |
| 98 { TOK_NONE, "" } | |
| 99 }; | |
| 100 | |
| 101 | |
| 102 struct parser_state | |
| 103 { | |
| 104 struct preproc_info *pp; // preprocessor data | |
| 105 struct token *curtok; // the current token | |
| 106 }; | |
| 107 | |
| 108 | |
| 109 struct token *parse_next(struct parser_state *ps) | |
| 110 { | |
| 111 struct token *tok; | |
| 112 int i; | |
| 113 | |
| 114 for (;;) | |
| 115 { | |
| 116 tok = preproc_next(ps -> pp); | |
| 117 if (tok -> ttype == TOK_WSPACE) | |
| 118 continue; | |
| 119 if (tok -> ttype == TOK_EOL) | |
| 120 continue; | |
| 121 if (tok -> ttype == TOK_CHAR) | |
| 122 { | |
| 123 // random character | |
| 124 fprintf(stderr, "Random character %02x\n", tok -> strval[0]); | |
| 125 if (tok -> strval[0] < 32 || tok -> strval[0] > 126) | |
| 126 continue; | |
| 127 } | |
| 128 break; | |
| 129 } | |
| 130 if (tok -> ttype == TOK_IDENT) | |
| 131 { | |
| 132 // convert identifier tokens to their respective meanings | |
| 133 for (i = 0; keyword_list[i].tok != TOK_NONE; i++) | |
| 134 { | |
| 135 if (strcmp(keyword_list[i].word, tok -> strval) == 0) | |
| 136 { | |
| 137 tok -> ttype = keyword_list[i].tok; | |
| 138 goto out; | |
| 139 } | |
| 140 } | |
| 141 // check for registered types here | |
| 142 } | |
| 143 else if (tok -> ttype == TOK_NUMBER) | |
| 144 { | |
| 145 // look for anything that isn't 0-9 | |
| 146 for (i = 0; tok -> strval[i]; i++) | |
| 147 { | |
| 148 if (tok -> strval[i] < '0' || tok -> strval[i] > '9') | |
| 149 break; | |
| 150 } | |
| 151 if (tok -> strval[i] == 0) | |
| 152 tok -> ttype = TOK_CONST_INT; | |
| 153 } | |
| 154 out: | |
| 155 fprintf(stderr, "Lexed: "); | |
| 156 token_print(tok, stderr); | |
| 157 fprintf(stderr, " (%d)\n", tok -> ttype); | |
| 158 if (ps -> curtok) | |
| 159 token_free(ps -> curtok); | |
| 160 ps -> curtok = tok; | |
| 161 return tok; | |
| 162 } | |
| 163 | |
| 164 void parse_generr(struct parser_state *ps, char *tag) | |
| 165 { | |
| 166 fprintf(stderr, "(%s) Unexpected token (%d): ", tag, ps -> curtok -> ttype); | |
| 167 token_print(ps -> curtok, stderr); | |
| 168 fprintf(stderr, "\n"); | |
| 169 | |
| 170 } | |
| 171 | |
|
501
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
172 node_t *parse_term_real(struct parser_state *ps) |
| 498 | 173 { |
| 174 node_t *rv; | |
|
501
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
175 |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
176 switch (ps -> curtok -> ttype) |
| 498 | 177 { |
|
501
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
178 case TOK_CONST_INT: |
| 498 | 179 rv = node_create(NODE_CONST_INT, ps -> curtok -> strval); |
| 180 parse_next(ps); | |
| 181 return rv; | |
| 182 } | |
|
501
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
183 |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
184 parse_generr(ps, "term"); |
| 498 | 185 return NULL; |
| 186 } | |
| 187 | |
|
501
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
188 node_t *parse_expr_real(struct parser_state *ps, int prec) |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
189 { |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
190 static struct { int tok; int nodetype; int prec; } operlist[] = { |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
191 { TOK_STAR, NODE_OPER_TIMES, 150 }, |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
192 { TOK_DIV, NODE_OPER_DIVIDE, 150 }, |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
193 { TOK_ADD, NODE_OPER_PLUS, 100 }, |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
194 { TOK_SUB, NODE_OPER_MINUS, 100 }, |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
195 { 0, 0, 0 } |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
196 }; |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
197 node_t *term1, *term2; |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
198 int i; |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
199 |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
200 term1 = parse_term_real(ps); |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
201 if (!term1) |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
202 return NULL; |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
203 |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
204 nextoper: |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
205 for (i = 0; operlist[i].tok; i++) |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
206 if (operlist[i].tok == ps -> curtok -> ttype) |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
207 break; |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
208 fprintf(stderr, "Matched operator: %d, %d\n", operlist[i].tok, operlist[i].prec); |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
209 // if we hit the end of the expression, return |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
210 if (operlist[i].tok == 0) |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
211 return term1; |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
212 |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
213 // is the next operator less or same precedence? |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
214 if (operlist[i].prec <= prec) |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
215 return term1; |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
216 |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
217 parse_next(ps); |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
218 term2 = parse_expr_real(ps, operlist[i].prec); |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
219 if (!term2) |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
220 { |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
221 parse_generr(ps, "expr"); |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
222 node_destroy(term2); |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
223 } |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
224 |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
225 term1 = node_create(operlist[i].nodetype, term1, term2); |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
226 term2 = NULL; |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
227 goto nextoper; |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
228 } |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
229 |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
230 node_t *parse_expr(struct parser_state *ps) |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
231 { |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
232 return parse_expr_real(ps, 0); |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
233 } |
|
f3e9732973f1
Add basic integer operations to lwcc
William Astle <lost@l-w.ca>
parents:
498
diff
changeset
|
234 |
| 498 | 235 node_t *parse_statement(struct parser_state *ps) |
| 236 { | |
| 237 node_t *rv; | |
| 238 node_t *n; | |
| 239 | |
| 240 switch (ps -> curtok -> ttype) | |
| 241 { | |
| 242 case TOK_KW_RETURN: | |
| 243 parse_next(ps); | |
| 244 n = parse_expr(ps); | |
| 245 if (!n) | |
| 246 { | |
| 247 parse_generr(ps, "statement"); | |
| 248 return NULL; | |
| 249 } | |
| 250 rv = node_create(NODE_STMT_RETURN); | |
| 251 node_addchild(rv, n); | |
| 252 break; | |
| 253 | |
| 254 default: | |
| 255 return NULL; | |
| 256 } | |
| 257 | |
| 258 if (ps -> curtok -> ttype != TOK_EOS) | |
| 259 parse_generr(ps, "statement"); | |
| 260 else | |
| 261 parse_next(ps); | |
| 262 return rv; | |
| 263 } | |
| 264 | |
| 265 node_t *parse_globaldecl(struct parser_state *ps) | |
| 266 { | |
| 267 node_t *rv = NULL; | |
| 268 node_t *stmt; | |
| 269 char *fnname = NULL; | |
| 270 if (ps -> curtok -> ttype == TOK_KW_INT) | |
| 271 { | |
| 272 // variable name | |
| 273 parse_next(ps); | |
| 274 if (ps -> curtok -> ttype != TOK_IDENT) | |
| 275 goto error; | |
| 276 fnname = lw_strdup(ps -> curtok -> strval); | |
| 277 parse_next(ps); | |
| 278 if (ps -> curtok -> ttype != TOK_OPAREN) | |
| 279 goto error; | |
| 280 parse_next(ps); | |
| 281 if (ps -> curtok -> ttype != TOK_CPAREN) | |
| 282 goto error; | |
| 283 parse_next(ps); | |
| 284 if (ps -> curtok -> ttype != TOK_OBRACE) | |
| 285 goto error; | |
| 286 parse_next(ps); | |
| 287 stmt = parse_statement(ps); | |
| 288 if (!stmt) | |
| 289 goto error; | |
| 290 rv = node_create(NODE_FUNDEF, node_create(NODE_TYPE_INT), node_create(NODE_IDENT, fnname), node_create(NODE_FUNARGS), stmt); | |
| 291 if (ps -> curtok -> ttype != TOK_CBRACE) | |
| 292 goto error; | |
| 293 parse_next(ps); | |
| 294 lw_free(fnname); | |
| 295 return rv; | |
| 296 } | |
| 297 | |
| 298 | |
| 299 error: | |
| 300 if (fnname) | |
| 301 lw_free(fnname); | |
| 302 parse_generr(ps, "globaldecl"); | |
| 303 return rv; | |
| 304 } | |
| 305 | |
| 306 node_t *parse_program(struct preproc_info *pp) | |
| 307 { | |
| 308 node_t *rv; | |
| 309 node_t *node; | |
| 310 struct parser_state ps; | |
| 311 | |
| 312 ps.pp = pp; | |
| 313 ps.curtok = NULL; | |
| 314 | |
| 315 rv = node_create(NODE_PROGRAM); | |
| 316 | |
| 317 // prime the parser | |
| 318 parse_next(&ps); | |
| 319 while (ps.curtok -> ttype != TOK_EOF) | |
| 320 { | |
| 321 node = parse_globaldecl(&ps); | |
| 322 if (!node) | |
| 323 break; | |
| 324 node_addchild(rv, node); | |
| 325 } | |
| 326 | |
| 327 return rv; | |
| 328 } |