ast.c

   1 /*
   2  * Copyright (C) 2012
   3  *     Wolfgang Bumiller
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a copy of
   6  * this software and associated documentation files (the "Software"), to deal in
   7  * the Software without restriction, including without limitation the rights to
   8  * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
   9  * of the Software, and to permit persons to whom the Software is furnished to do
  10  * so, subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice shall be included in all
  13  * copies or substantial portions of the Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  18  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  20  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  21  * SOFTWARE.
  22  */
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26
  27 #include "gmqcc.h"
  28 #include "ast.h"
  29
  30 #define ast_instantiate(T, ctx, destroyfn)                          \
  31     T* self = (T*)mem_a(sizeof(T));                                 \
  32     if (!self) {                                                    \
  33         return NULL;                                                \
  34     }                                                               \
  35     ast_node_init((ast_node*)self, ctx);                            \
  36     ( (ast_node*)self )->node.destroy = (ast_node_delete*)destroyfn
  37
  38 /* It must not be possible to get here. */
  39 static void _ast_node_destroy(ast_node *self)
  40 {
  41     fprintf(stderr, "ast node missing destroy()\n");
  42     abort();
  43 }
  44
  45 /* Initialize main ast node aprts */
  46 static void ast_node_init(ast_node *self, lex_ctx ctx)
  47 {
  48     self->node.context = ctx;
  49     self->node.destroy = &_ast_node_destroy;
  50     self->node.keep    = false;
  51 }
  52
  53 /* General expression initialization */
  54 static void ast_expression_init(ast_expression *self,
  55                                 ast_expression_codegen *codegen)
  56 {
  57     self->expression.codegen = codegen;
  58 }
  59
  60 ast_value* ast_value_new(lex_ctx ctx, const char *name, int t)
  61 {
  62     ast_instantiate(ast_value, ctx, ast_value_delete);
  63     ast_expression_init((ast_expression*)self,
  64                         (ast_expression_codegen*)&ast_value_codegen);
  65     self->expression.node.keep = true; /* keep */
  66
  67     self->name = name ? util_strdup(name) : NULL;
  68     self->vtype = t;
  69     self->next = NULL;
  70     MEM_VECTOR_INIT(self, params);
  71     self->isconst = false;
  72     memset(&self->constval, 0, sizeof(self->constval));
  73
  74     self->ir_v    = NULL;
  75
  76     return self;
  77 }
  78 MEM_VEC_FUNCTIONS(ast_value, ast_value*, params)
  79
  80 void ast_value_delete(ast_value* self)
  81 {
  82     size_t i;
  83     if (self->name)
  84         mem_d((void*)self->name);
  85     for (i = 0; i < self->params_count; ++i)
  86         ast_value_delete(self->params[i]); /* delete, the ast_function is expected to die first */
  87     MEM_VECTOR_CLEAR(self, params);
  88     if (self->next) /* delete, not unref, types are always copied */
  89         ast_delete(self->next);
  90     if (self->isconst) {
  91         switch (self->vtype)
  92         {
  93         case TYPE_STRING:
  94             mem_d((void*)self->constval.vstring);
  95             break;
  96         case TYPE_FUNCTION:
  97             /* unlink us from the function node */
  98             self->constval.vfunc->vtype = NULL;
  99             break;
 100         /* NOTE: delete function? currently collected in
 101          * the parser structure
 102          */
 103         default:
 104             break;
 105         }
 106     }
 107     mem_d(self);
 108 }
 109
 110 bool ast_value_set_name(ast_value *self, const char *name)
 111 {
 112     if (self->name)
 113         mem_d((void*)self->name);
 114     self->name = util_strdup(name);
 115     return !!self->name;
 116 }
 117
 118 ast_binary* ast_binary_new(lex_ctx ctx, int op,
 119                            ast_expression* left, ast_expression* right)
 120 {
 121     ast_instantiate(ast_binary, ctx, ast_binary_delete);
 122     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_binary_codegen);
 123
 124     self->op = op;
 125     self->left = left;
 126     self->right = right;
 127
 128     return self;
 129 }
 130
 131 void ast_binary_delete(ast_binary *self)
 132 {
 133     ast_unref(self->left);
 134     ast_unref(self->right);
 135     mem_d(self);
 136 }
 137
 138 ast_entfield* ast_entfield_new(lex_ctx ctx, ast_expression *entity, ast_expression *field)
 139 {
 140     ast_instantiate(ast_entfield, ctx, ast_entfield_delete);
 141     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_entfield_codegen);
 142
 143     self->entity = entity;
 144     self->field  = field;
 145
 146     return self;
 147 }
 148
 149 void ast_entfield_delete(ast_entfield *self)
 150 {
 151     ast_unref(self->entity);
 152     ast_unref(self->field);
 153     mem_d(self);
 154 }
 155
 156 ast_ifthen* ast_ifthen_new(lex_ctx ctx, ast_expression *cond, ast_expression *ontrue, ast_expression *onfalse)
 157 {
 158     ast_instantiate(ast_ifthen, ctx, ast_ifthen_delete);
 159     if (!ontrue && !onfalse) {
 160         /* because it is invalid */
 161         mem_d(self);
 162         return NULL;
 163     }
 164     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_ifthen_codegen);
 165
 166     self->cond     = cond;
 167     self->on_true  = ontrue;
 168     self->on_false = onfalse;
 169
 170     return self;
 171 }
 172
 173 void ast_ifthen_delete(ast_ifthen *self)
 174 {
 175     ast_unref(self->cond);
 176     ast_unref(self->on_true);
 177     ast_unref(self->on_false);
 178     mem_d(self);
 179 }
 180
 181 ast_ternary* ast_ternary_new(lex_ctx ctx, ast_expression *cond, ast_expression *ontrue, ast_expression *onfalse)
 182 {
 183     ast_instantiate(ast_ternary, ctx, ast_ternary_delete);
 184     /* This time NEITHER must be NULL */
 185     if (!ontrue || !onfalse) {
 186         mem_d(self);
 187         return NULL;
 188     }
 189     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_ternary_codegen);
 190
 191     self->cond     = cond;
 192     self->on_true  = ontrue;
 193     self->on_false = onfalse;
 194     self->phi_out  = NULL;
 195
 196     return self;
 197 }
 198
 199 void ast_ternary_delete(ast_ternary *self)
 200 {
 201     ast_unref(self->cond);
 202     ast_unref(self->on_true);
 203     ast_unref(self->on_false);
 204     mem_d(self);
 205 }
 206
 207 ast_store* ast_store_new(lex_ctx ctx, int op,
 208                          ast_value *dest, ast_expression *source)
 209 {
 210     ast_instantiate(ast_store, ctx, ast_store_delete);
 211     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_store_codegen);
 212
 213     self->op = op;
 214     self->dest = dest;
 215     self->source = source;
 216
 217     return self;
 218 }
 219
 220 void ast_store_delete(ast_store *self)
 221 {
 222     ast_unref(self->dest);
 223     ast_unref(self->source);
 224     mem_d(self);
 225 }
 226
 227 ast_block* ast_block_new(lex_ctx ctx)
 228 {
 229     ast_instantiate(ast_block, ctx, ast_block_delete);
 230     ast_expression_init((ast_expression*)self,
 231                         (ast_expression_codegen*)&ast_block_codegen);
 232
 233     MEM_VECTOR_INIT(self, locals);
 234     MEM_VECTOR_INIT(self, exprs);
 235
 236     return self;
 237 }
 238 MEM_VEC_FUNCTIONS(ast_block, ast_value*, locals)
 239 MEM_VEC_FUNCTIONS(ast_block, ast_expression*, exprs)
 240
 241 void ast_block_delete(ast_block *self)
 242 {
 243     size_t i;
 244     for (i = 0; i < self->exprs_count; ++i)
 245         ast_unref(self->exprs[i]);
 246     MEM_VECTOR_CLEAR(self, exprs);
 247     for (i = 0; i < self->locals_count; ++i)
 248         ast_delete(self->locals[i]);
 249     MEM_VECTOR_CLEAR(self, locals);
 250     mem_d(self);
 251 }
 252
 253 ast_function* ast_function_new(lex_ctx ctx, const char *name, ast_value *vtype)
 254 {
 255     ast_instantiate(ast_function, ctx, ast_function_delete);
 256
 257     if (!vtype ||
 258         vtype->isconst ||
 259         vtype->vtype != TYPE_FUNCTION)
 260     {
 261         mem_d(self);
 262         return NULL;
 263     }
 264
 265     self->vtype = vtype;
 266     self->name = name ? util_strdup(name) : NULL;
 267     MEM_VECTOR_INIT(self, blocks);
 268
 269     self->ir_func = NULL;
 270
 271     vtype->isconst = true;
 272     vtype->constval.vfunc = self;
 273
 274     return self;
 275 }
 276
 277 MEM_VEC_FUNCTIONS(ast_function, ast_block*, blocks)
 278
 279 void ast_function_delete(ast_function *self)
 280 {
 281     size_t i;
 282     if (self->name)
 283         mem_d((void*)self->name);
 284     if (self->vtype) {
 285         /* ast_value_delete(self->vtype); */
 286         self->vtype->isconst = false;
 287         self->vtype->constval.vfunc = NULL;
 288         /* We use unref - if it was stored in a global table it is supposed
 289          * to be deleted from *there*
 290          */
 291         ast_unref(self->vtype);
 292     }
 293     for (i = 0; i < self->blocks_count; ++i)
 294         ast_delete(self->blocks[i]);
 295     MEM_VECTOR_CLEAR(self, blocks);
 296     mem_d(self);
 297 }
 298
 299 /*********************************************************************/
 300 /* AST codegen part
 301  * by convention you must never pass NULL to the 'ir_value **out'
 302  * parameter. If you really don't care about the output, pass a dummy.
 303  * But I can't imagine a pituation where the output is truly unnecessary.
 304  */
 305
 306 bool ast_value_codegen(ast_value *self, ast_function *func, bool lvalue, ir_value **out)
 307 {
 308     /* NOTE: This is the codegen for a variable used in an expression.
 309      * It is not the codegen to generate the value. For this purpose,
 310      * ast_local_codegen and ast_global_codegen are to be used before this
 311      * is executed. ast_function_codegen should take care of its locals,
 312      * and the ast-user should take care of ast_global_codegen to be used
 313      * on all the globals.
 314      */
 315     if (!self->ir_v)
 316         return false;
 317     *out = self->ir_v;
 318     return true;
 319 }
 320
 321 bool ast_global_codegen(ast_value *self, ir_builder *ir)
 322 {
 323     ir_value *v = NULL;
 324     if (self->isconst && self->vtype == TYPE_FUNCTION)
 325     {
 326         ir_function *func = ir_builder_create_function(ir, self->name);
 327         if (!func)
 328             return false;
 329
 330         self->constval.vfunc->ir_func = func;
 331         /* The function is filled later on ast_function_codegen... */
 332         return true;
 333     }
 334
 335     v = ir_builder_create_global(ir, self->name, self->vtype);
 336     if (!v)
 337         return false;
 338
 339     if (self->isconst) {
 340         switch (self->vtype)
 341         {
 342             case TYPE_FLOAT:
 343                 if (!ir_value_set_float(v, self->constval.vfloat))
 344                     goto error;
 345                 break;
 346             case TYPE_VECTOR:
 347                 if (!ir_value_set_vector(v, self->constval.vvec))
 348                     goto error;
 349                 break;
 350             case TYPE_STRING:
 351                 if (!ir_value_set_string(v, self->constval.vstring))
 352                     goto error;
 353                 break;
 354             case TYPE_FUNCTION:
 355                 /* Cannot generate an IR value for a function,
 356                  * need a pointer pointing to a function rather.
 357                  */
 358                 goto error;
 359             default:
 360                 printf("TODO: global constant type %i\n", self->vtype);
 361                 break;
 362         }
 363     }
 364
 365     /* link us to the ir_value */
 366     self->ir_v = v;
 367     return true;
 368
 369 error: /* clean up */
 370     ir_value_delete(v);
 371     return false;
 372 }
 373
 374 bool ast_local_codegen(ast_value *self, ir_function *func)
 375 {
 376     ir_value *v = NULL;
 377     if (self->isconst && self->vtype == TYPE_FUNCTION)
 378     {
 379         /* Do we allow local functions? I think not...
 380          * this is NOT a function pointer atm.
 381          */
 382         return false;
 383     }
 384
 385     v = ir_function_create_local(func, self->name, self->vtype);
 386     if (!v)
 387         return false;
 388
 389     /* A constant local... hmmm...
 390      * I suppose the IR will have to deal with this
 391      */
 392     if (self->isconst) {
 393         switch (self->vtype)
 394         {
 395             case TYPE_FLOAT:
 396                 if (!ir_value_set_float(v, self->constval.vfloat))
 397                     goto error;
 398                 break;
 399             case TYPE_VECTOR:
 400                 if (!ir_value_set_vector(v, self->constval.vvec))
 401                     goto error;
 402                 break;
 403             case TYPE_STRING:
 404                 if (!ir_value_set_string(v, self->constval.vstring))
 405                     goto error;
 406                 break;
 407             default:
 408                 printf("TODO: global constant type %i\n", self->vtype);
 409                 break;
 410         }
 411     }
 412
 413     /* link us to the ir_value */
 414     self->ir_v = v;
 415     return true;
 416
 417 error: /* clean up */
 418     ir_value_delete(v);
 419     return false;
 420 }
 421
 422 bool ast_function_codegen(ast_function *self, ir_builder *ir)
 423 {
 424     ir_value *dummy;
 425     size_t    i;
 426     if (!self->ir_func) {
 427         printf("ast_function's related ast_value was not generated yet\n");
 428         return false;
 429     }
 430
 431     for (i = 0; i < self->blocks_count; ++i) {
 432         ast_expression_codegen *gen = self->blocks[i]->expression.codegen;
 433         if (!(*gen)((ast_expression*)self->blocks[i], self, false, &dummy))
 434             return false;
 435     }
 436     return true;
 437 }
 438
 439 bool ast_block_codegen(ast_block *self, ast_function *func, bool lvalue, ir_value **out)
 440 {
 441     return false;
 442 }
 443
 444 bool ast_store_codegen(ast_store *self, ast_function *func, bool lvalue, ir_value **out)
 445 {
 446     /* NOTE: remember: destination codegen needs to have lvalue=true */
 447     return false;
 448 }
 449
 450 bool ast_binary_codegen(ast_binary *self, ast_function *func, bool lvalue, ir_value **out)
 451 {
 452     return false;
 453 }
 454
 455 bool ast_entfield_codegen(ast_entfield *self, ast_function *func, bool lvalue, ir_value **out)
 456 {
 457     return false;
 458 }
 459
 460 bool ast_ifthen_codegen(ast_ifthen *self, ast_function *func, bool lvalue, ir_value **out)
 461 {
 462     if (out) *out = NULL;
 463     return false;
 464 }
 465
 466 bool ast_ternary_codegen(ast_ternary *self, ast_function *func, bool lvalue, ir_value **out)
 467 {
 468     /* In theory it shouldn't be possible to pass through a node twice, but
 469      * in case we add any kind of optimization pass for the AST itself, it
 470      * may still happen, thus we remember a created ir_value and simply return one
 471      * if it already exists.
 472      */
 473     if (self->phi_out) {
 474         *out = self->phi_out;
 475         return true;
 476     }
 477     return false;
 478 }