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     self->expression.vtype   = TYPE_VOID;
  59     self->expression.next    = NULL;
  60 }
  61
  62 static void ast_expression_delete(ast_expression *self)
  63 {
  64     if (self->expression.next)
  65         ast_delete(self->expression.next);
  66 }
  67
  68 static void ast_expression_delete_full(ast_expression *self)
  69 {
  70     ast_expression_delete(self);
  71     mem_d(self);
  72 }
  73
  74 static ast_expression* ast_type_copy(lex_ctx ctx, const ast_expression *ex)
  75 {
  76     const ast_expression_common *cpex;
  77     ast_expression_common *selfex;
  78
  79     if (!ex)
  80         return NULL;
  81     else
  82     {
  83         ast_instantiate(ast_expression, ctx, ast_expression_delete_full);
  84
  85         cpex   = &ex->expression;
  86         selfex = &self->expression;
  87
  88         selfex->vtype = cpex->vtype;
  89         if (cpex->next)
  90         {
  91             selfex->next = ast_type_copy(ctx, cpex->next);
  92             if (!selfex->next) {
  93                 mem_d(self);
  94                 return NULL;
  95             }
  96         }
  97         else
  98             selfex->next = NULL;
  99
 100         /* This may never be codegen()d */
 101         selfex->codegen = NULL;
 102         return self;
 103     }
 104 }
 105
 106 ast_value* ast_value_new(lex_ctx ctx, const char *name, int t)
 107 {
 108     ast_instantiate(ast_value, ctx, ast_value_delete);
 109     ast_expression_init((ast_expression*)self,
 110                         (ast_expression_codegen*)&ast_value_codegen);
 111     self->expression.node.keep = true; /* keep */
 112
 113     self->name = name ? util_strdup(name) : NULL;
 114     self->expression.vtype = t;
 115     self->expression.next  = NULL;
 116     MEM_VECTOR_INIT(self, params);
 117     self->isconst = false;
 118     memset(&self->constval, 0, sizeof(self->constval));
 119
 120     self->ir_v    = NULL;
 121
 122     return self;
 123 }
 124 MEM_VEC_FUNCTIONS(ast_value, ast_value*, params)
 125
 126 void ast_value_delete(ast_value* self)
 127 {
 128     size_t i;
 129     if (self->name)
 130         mem_d((void*)self->name);
 131     for (i = 0; i < self->params_count; ++i)
 132         ast_value_delete(self->params[i]); /* delete, the ast_function is expected to die first */
 133     MEM_VECTOR_CLEAR(self, params);
 134     if (self->isconst) {
 135         switch (self->expression.vtype)
 136         {
 137         case TYPE_STRING:
 138             mem_d((void*)self->constval.vstring);
 139             break;
 140         case TYPE_FUNCTION:
 141             /* unlink us from the function node */
 142             self->constval.vfunc->vtype = NULL;
 143             break;
 144         /* NOTE: delete function? currently collected in
 145          * the parser structure
 146          */
 147         default:
 148             break;
 149         }
 150     }
 151     ast_expression_delete((ast_expression*)self);
 152     mem_d(self);
 153 }
 154
 155 bool ast_value_set_name(ast_value *self, const char *name)
 156 {
 157     if (self->name)
 158         mem_d((void*)self->name);
 159     self->name = util_strdup(name);
 160     return !!self->name;
 161 }
 162
 163 ast_binary* ast_binary_new(lex_ctx ctx, int op,
 164                            ast_expression* left, ast_expression* right)
 165 {
 166     ast_instantiate(ast_binary, ctx, ast_binary_delete);
 167     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_binary_codegen);
 168
 169     self->op = op;
 170     self->left = left;
 171     self->right = right;
 172
 173     return self;
 174 }
 175
 176 void ast_binary_delete(ast_binary *self)
 177 {
 178     ast_unref(self->left);
 179     ast_unref(self->right);
 180     ast_expression_delete((ast_expression*)self);
 181     mem_d(self);
 182 }
 183
 184 ast_entfield* ast_entfield_new(lex_ctx ctx, ast_expression *entity, ast_expression *field)
 185 {
 186     const ast_expression *outtype;
 187
 188     ast_instantiate(ast_entfield, ctx, ast_entfield_delete);
 189
 190     if (field->expression.vtype != TYPE_FIELD) {
 191         mem_d(self);
 192         return NULL;
 193     }
 194
 195     outtype = field->expression.next;
 196     if (!outtype) {
 197         mem_d(self);
 198         /* Error: field has no type... */
 199         return NULL;
 200     }
 201
 202     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_entfield_codegen);
 203
 204     self->expression.vtype = outtype->expression.vtype;
 205     self->expression.next  = ast_type_copy(ctx, outtype->expression.next);
 206
 207     self->entity = entity;
 208     self->field  = field;
 209
 210     return self;
 211 }
 212
 213 void ast_entfield_delete(ast_entfield *self)
 214 {
 215     ast_unref(self->entity);
 216     ast_unref(self->field);
 217     ast_expression_delete((ast_expression*)self);
 218     mem_d(self);
 219 }
 220
 221 ast_ifthen* ast_ifthen_new(lex_ctx ctx, ast_expression *cond, ast_expression *ontrue, ast_expression *onfalse)
 222 {
 223     ast_instantiate(ast_ifthen, ctx, ast_ifthen_delete);
 224     if (!ontrue && !onfalse) {
 225         /* because it is invalid */
 226         mem_d(self);
 227         return NULL;
 228     }
 229     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_ifthen_codegen);
 230
 231     self->cond     = cond;
 232     self->on_true  = ontrue;
 233     self->on_false = onfalse;
 234
 235     return self;
 236 }
 237
 238 void ast_ifthen_delete(ast_ifthen *self)
 239 {
 240     ast_unref(self->cond);
 241     ast_unref(self->on_true);
 242     ast_unref(self->on_false);
 243     ast_expression_delete((ast_expression*)self);
 244     mem_d(self);
 245 }
 246
 247 ast_ternary* ast_ternary_new(lex_ctx ctx, ast_expression *cond, ast_expression *ontrue, ast_expression *onfalse)
 248 {
 249     ast_instantiate(ast_ternary, ctx, ast_ternary_delete);
 250     /* This time NEITHER must be NULL */
 251     if (!ontrue || !onfalse) {
 252         mem_d(self);
 253         return NULL;
 254     }
 255     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_ternary_codegen);
 256
 257     self->cond     = cond;
 258     self->on_true  = ontrue;
 259     self->on_false = onfalse;
 260     self->phi_out  = NULL;
 261
 262     return self;
 263 }
 264
 265 void ast_ternary_delete(ast_ternary *self)
 266 {
 267     ast_unref(self->cond);
 268     ast_unref(self->on_true);
 269     ast_unref(self->on_false);
 270     ast_expression_delete((ast_expression*)self);
 271     mem_d(self);
 272 }
 273
 274 ast_store* ast_store_new(lex_ctx ctx, int op,
 275                          ast_value *dest, ast_expression *source)
 276 {
 277     ast_instantiate(ast_store, ctx, ast_store_delete);
 278     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_store_codegen);
 279
 280     self->op = op;
 281     self->dest = dest;
 282     self->source = source;
 283
 284     return self;
 285 }
 286
 287 void ast_store_delete(ast_store *self)
 288 {
 289     ast_unref(self->dest);
 290     ast_unref(self->source);
 291     ast_expression_delete((ast_expression*)self);
 292     mem_d(self);
 293 }
 294
 295 ast_block* ast_block_new(lex_ctx ctx)
 296 {
 297     ast_instantiate(ast_block, ctx, ast_block_delete);
 298     ast_expression_init((ast_expression*)self,
 299                         (ast_expression_codegen*)&ast_block_codegen);
 300
 301     MEM_VECTOR_INIT(self, locals);
 302     MEM_VECTOR_INIT(self, exprs);
 303
 304     return self;
 305 }
 306 MEM_VEC_FUNCTIONS(ast_block, ast_value*, locals)
 307 MEM_VEC_FUNCTIONS(ast_block, ast_expression*, exprs)
 308
 309 void ast_block_delete(ast_block *self)
 310 {
 311     size_t i;
 312     for (i = 0; i < self->exprs_count; ++i)
 313         ast_unref(self->exprs[i]);
 314     MEM_VECTOR_CLEAR(self, exprs);
 315     for (i = 0; i < self->locals_count; ++i)
 316         ast_delete(self->locals[i]);
 317     MEM_VECTOR_CLEAR(self, locals);
 318     ast_expression_delete((ast_expression*)self);
 319     mem_d(self);
 320 }
 321
 322 ast_function* ast_function_new(lex_ctx ctx, const char *name, ast_value *vtype)
 323 {
 324     ast_instantiate(ast_function, ctx, ast_function_delete);
 325
 326     if (!vtype ||
 327         vtype->isconst ||
 328         vtype->expression.vtype != TYPE_FUNCTION)
 329     {
 330         mem_d(self);
 331         return NULL;
 332     }
 333
 334     self->vtype = vtype;
 335     self->name = name ? util_strdup(name) : NULL;
 336     MEM_VECTOR_INIT(self, blocks);
 337
 338     self->labelcount = 0;
 339
 340     self->ir_func = NULL;
 341     self->curblock = NULL;
 342
 343     vtype->isconst = true;
 344     vtype->constval.vfunc = self;
 345
 346     return self;
 347 }
 348
 349 MEM_VEC_FUNCTIONS(ast_function, ast_block*, blocks)
 350
 351 void ast_function_delete(ast_function *self)
 352 {
 353     size_t i;
 354     if (self->name)
 355         mem_d((void*)self->name);
 356     if (self->vtype) {
 357         /* ast_value_delete(self->vtype); */
 358         self->vtype->isconst = false;
 359         self->vtype->constval.vfunc = NULL;
 360         /* We use unref - if it was stored in a global table it is supposed
 361          * to be deleted from *there*
 362          */
 363         ast_unref(self->vtype);
 364     }
 365     for (i = 0; i < self->blocks_count; ++i)
 366         ast_delete(self->blocks[i]);
 367     MEM_VECTOR_CLEAR(self, blocks);
 368     mem_d(self);
 369 }
 370
 371 const char* ast_function_label(ast_function *self, const char *prefix)
 372 {
 373     size_t id = (self->labelcount++);
 374     sprintf(self->labelbuf, "%16s%8u", prefix, (unsigned int)id);
 375     return self->labelbuf;
 376 }
 377
 378 /*********************************************************************/
 379 /* AST codegen part
 380  * by convention you must never pass NULL to the 'ir_value **out'
 381  * parameter. If you really don't care about the output, pass a dummy.
 382  * But I can't imagine a pituation where the output is truly unnecessary.
 383  */
 384
 385 bool ast_value_codegen(ast_value *self, ast_function *func, bool lvalue, ir_value **out)
 386 {
 387     /* NOTE: This is the codegen for a variable used in an expression.
 388      * It is not the codegen to generate the value. For this purpose,
 389      * ast_local_codegen and ast_global_codegen are to be used before this
 390      * is executed. ast_function_codegen should take care of its locals,
 391      * and the ast-user should take care of ast_global_codegen to be used
 392      * on all the globals.
 393      */
 394     if (!self->ir_v)
 395         return false;
 396     *out = self->ir_v;
 397     return true;
 398 }
 399
 400 bool ast_global_codegen(ast_value *self, ir_builder *ir)
 401 {
 402     ir_value *v = NULL;
 403     if (self->isconst && self->expression.vtype == TYPE_FUNCTION)
 404     {
 405         ir_function *func = ir_builder_create_function(ir, self->name);
 406         if (!func)
 407             return false;
 408
 409         self->constval.vfunc->ir_func = func;
 410         /* The function is filled later on ast_function_codegen... */
 411         return true;
 412     }
 413
 414     v = ir_builder_create_global(ir, self->name, self->expression.vtype);
 415     if (!v)
 416         return false;
 417
 418     if (self->isconst) {
 419         switch (self->expression.vtype)
 420         {
 421             case TYPE_FLOAT:
 422                 if (!ir_value_set_float(v, self->constval.vfloat))
 423                     goto error;
 424                 break;
 425             case TYPE_VECTOR:
 426                 if (!ir_value_set_vector(v, self->constval.vvec))
 427                     goto error;
 428                 break;
 429             case TYPE_STRING:
 430                 if (!ir_value_set_string(v, self->constval.vstring))
 431                     goto error;
 432                 break;
 433             case TYPE_FUNCTION:
 434                 /* Cannot generate an IR value for a function,
 435                  * need a pointer pointing to a function rather.
 436                  */
 437                 goto error;
 438             default:
 439                 printf("TODO: global constant type %i\n", self->expression.vtype);
 440                 break;
 441         }
 442     }
 443
 444     /* link us to the ir_value */
 445     self->ir_v = v;
 446     return true;
 447
 448 error: /* clean up */
 449     ir_value_delete(v);
 450     return false;
 451 }
 452
 453 bool ast_local_codegen(ast_value *self, ir_function *func)
 454 {
 455     ir_value *v = NULL;
 456     if (self->isconst && self->expression.vtype == TYPE_FUNCTION)
 457     {
 458         /* Do we allow local functions? I think not...
 459          * this is NOT a function pointer atm.
 460          */
 461         return false;
 462     }
 463
 464     v = ir_function_create_local(func, self->name, self->expression.vtype);
 465     if (!v)
 466         return false;
 467
 468     /* A constant local... hmmm...
 469      * I suppose the IR will have to deal with this
 470      */
 471     if (self->isconst) {
 472         switch (self->expression.vtype)
 473         {
 474             case TYPE_FLOAT:
 475                 if (!ir_value_set_float(v, self->constval.vfloat))
 476                     goto error;
 477                 break;
 478             case TYPE_VECTOR:
 479                 if (!ir_value_set_vector(v, self->constval.vvec))
 480                     goto error;
 481                 break;
 482             case TYPE_STRING:
 483                 if (!ir_value_set_string(v, self->constval.vstring))
 484                     goto error;
 485                 break;
 486             default:
 487                 printf("TODO: global constant type %i\n", self->expression.vtype);
 488                 break;
 489         }
 490     }
 491
 492     /* link us to the ir_value */
 493     self->ir_v = v;
 494     return true;
 495
 496 error: /* clean up */
 497     ir_value_delete(v);
 498     return false;
 499 }
 500
 501 bool ast_function_codegen(ast_function *self, ir_builder *ir)
 502 {
 503     ir_function *irf;
 504     ir_value    *dummy;
 505     size_t    i;
 506
 507     irf = self->ir_func;
 508     if (!irf) {
 509         printf("ast_function's related ast_value was not generated yet\n");
 510         return false;
 511     }
 512
 513     self->curblock = ir_function_create_block(irf, "entry");
 514     if (!self->curblock)
 515         return false;
 516
 517     for (i = 0; i < self->blocks_count; ++i) {
 518         ast_expression_codegen *gen = self->blocks[i]->expression.codegen;
 519         if (!(*gen)((ast_expression*)self->blocks[i], self, false, &dummy))
 520             return false;
 521     }
 522     return true;
 523 }
 524
 525 /* Note, you will not see ast_block_codegen generate ir_blocks.
 526  * To the AST and the IR, blocks are 2 different things.
 527  * In the AST it represents a block of code, usually enclosed in
 528  * curly braces {...}.
 529  * While in the IR it represents a block in terms of control-flow.
 530  */
 531 bool ast_block_codegen(ast_block *self, ast_function *func, bool lvalue, ir_value **out)
 532 {
 533     size_t i;
 534
 535     /* We don't use this
 536      * Note: an ast-representation using the comma-operator
 537      * of the form: (a, b, c) = x should not assign to c...
 538      */
 539     (void)lvalue;
 540
 541     /* output is NULL at first, we'll have each expression
 542      * assign to out output, thus, a comma-operator represention
 543      * using an ast_block will return the last generated value,
 544      * so: (b, c) + a  executed both b and c, and returns c,
 545      * which is then added to a.
 546      */
 547     *out = NULL;
 548
 549     /* generate locals */
 550     for (i = 0; i < self->locals_count; ++i)
 551     {
 552         if (!ast_local_codegen(self->locals[i], func->ir_func))
 553             return false;
 554     }
 555
 556     for (i = 0; i < self->exprs_count; ++i)
 557     {
 558         ast_expression_codegen *gen = self->exprs[i]->expression.codegen;
 559         if (!(*gen)(self->exprs[i], func, false, out))
 560             return false;
 561     }
 562
 563     return true;
 564 }
 565
 566 bool ast_store_codegen(ast_store *self, ast_function *func, bool lvalue, ir_value **out)
 567 {
 568     ast_expression_codegen *cgen;
 569     ir_value *left, *right;
 570
 571     cgen = self->dest->expression.codegen;
 572     /* lvalue! */
 573     if (!(*cgen)((ast_expression*)(self->dest), func, true, &left))
 574         return false;
 575
 576     cgen = self->source->expression.codegen;
 577     /* rvalue! */
 578     if (!(*cgen)((ast_expression*)(self->source), func, false, &right))
 579         return false;
 580
 581     if (!ir_block_create_store_op(func->curblock, self->op, left, right))
 582         return false;
 583
 584     /* Theoretically, an assinment returns its left side as an
 585      * lvalue, if we don't need an lvalue though, we return
 586      * the right side as an rvalue, otherwise we have to
 587      * somehow know whether or not we need to dereference the pointer
 588      * on the left side - that is: OP_LOAD if it was an address.
 589      * Also: in original QC we cannot OP_LOADP *anyway*.
 590      */
 591     *out = (lvalue ? left : right);
 592
 593     return true;
 594 }
 595
 596 bool ast_binary_codegen(ast_binary *self, ast_function *func, bool lvalue, ir_value **out)
 597 {
 598     ast_expression_codegen *cgen;
 599     ir_value *left, *right;
 600
 601     /* In the context of a binary operation, we can disregard
 602      * the lvalue flag.
 603      */
 604      (void)lvalue;
 605
 606     cgen = self->left->expression.codegen;
 607     /* lvalue! */
 608     if (!(*cgen)((ast_expression*)(self->left), func, false, &left))
 609         return false;
 610
 611     cgen = self->right->expression.codegen;
 612     /* rvalue! */
 613     if (!(*cgen)((ast_expression*)(self->right), func, false, &right))
 614         return false;
 615
 616     *out = ir_block_create_binop(func->curblock, ast_function_label(func, "bin"),
 617                                  self->op, left, right);
 618     if (!*out)
 619         return false;
 620
 621     return true;
 622 }
 623
 624 bool ast_entfield_codegen(ast_entfield *self, ast_function *func, bool lvalue, ir_value **out)
 625 {
 626     ast_expression_codegen *cgen;
 627     ir_value *ent, *field;
 628
 629     /* This function needs to take the 'lvalue' flag into account!
 630      * As lvalue we provide a field-pointer, as rvalue we provide the
 631      * value in a temp.
 632      */
 633
 634     cgen = self->entity->expression.codegen;
 635     if (!(*cgen)((ast_expression*)(self->entity), func, false, &ent))
 636         return false;
 637
 638     cgen = self->field->expression.codegen;
 639     if (!(*cgen)((ast_expression*)(self->field), func, false, &field))
 640         return false;
 641
 642     if (lvalue) {
 643         /* address! */
 644         *out = ir_block_create_fieldaddress(func->curblock, ast_function_label(func, "efa"),
 645                                             ent, field);
 646     } else {
 647         *out = ir_block_create_load_from_ent(func->curblock, ast_function_label(func, "efv"),
 648                                              ent, field, self->expression.vtype);
 649     }
 650     if (!*out)
 651         return false;
 652
 653     /* Hm that should be it... */
 654     return true;
 655 }
 656
 657 bool ast_ifthen_codegen(ast_ifthen *self, ast_function *func, bool lvalue, ir_value **out)
 658 {
 659     ast_expression_codegen *cgen;
 660
 661     ir_value *condval;
 662     ir_value *dummy;
 663
 664     ir_block *cond = func->curblock;
 665     ir_block *ontrue;
 666     ir_block *onfalse;
 667     ir_block *merge;
 668
 669     /* We don't output any value, thus also don't care about r/lvalue */
 670     (void)out;
 671     (void)lvalue;
 672
 673     /* create blocks first, it's nicer if they're ordered */
 674
 675     if (self->on_true) {
 676         /* create on-true block */
 677         ontrue = ir_function_create_block(func->ir_func, ast_function_label(func, "ontrue"));
 678         if (!ontrue)
 679             return false;
 680     } else
 681         ontrue = NULL;
 682
 683     if (self->on_false) {
 684         /* create on-false block */
 685         onfalse = ir_function_create_block(func->ir_func, ast_function_label(func, "onfalse"));
 686         if (!onfalse)
 687             return false;
 688     } else
 689         onfalse = NULL;
 690
 691     merge = ir_function_create_block(func->ir_func, ast_function_label(func, "endif"));
 692     if (!merge)
 693         return NULL;
 694
 695     /* generate the condition */
 696     func->curblock = cond;
 697     cgen = self->cond->expression.codegen;
 698     if (!(*cgen)((ast_expression*)(self->cond), func, false, &condval))
 699         return false;
 700
 701     if (!ir_block_create_if(cond, condval,
 702                             (ontrue  ? ontrue  : merge),
 703                             (onfalse ? onfalse : merge)))
 704     {
 705         return false;
 706     }
 707
 708     /* on-true path */
 709     if (ontrue) {
 710         /* enter the block */
 711         func->curblock = ontrue;
 712
 713         /* generate */
 714         cgen = self->on_true->expression.codegen;
 715         if (!(*cgen)((ast_expression*)(self->on_true), func, false, &dummy))
 716             return false;
 717
 718         /* jump to merge block */
 719         if (!ir_block_create_jump(ontrue, merge))
 720             return false;
 721     }
 722
 723     /* on-false path */
 724     if (onfalse) {
 725         /* enter the block */
 726         func->curblock = onfalse;
 727
 728         /* generate */
 729         cgen = self->on_false->expression.codegen;
 730         if (!(*cgen)((ast_expression*)(self->on_false), func, false, &dummy))
 731             return false;
 732
 733         /* jump to merge block */
 734         if (!ir_block_create_jump(ontrue, merge))
 735             return false;
 736     }
 737
 738     /* Now enter the merge block */
 739     func->curblock = merge;
 740
 741     return true;
 742 }
 743
 744 bool ast_ternary_codegen(ast_ternary *self, ast_function *func, bool lvalue, ir_value **out)
 745 {
 746     /* In theory it shouldn't be possible to pass through a node twice, but
 747      * in case we add any kind of optimization pass for the AST itself, it
 748      * may still happen, thus we remember a created ir_value and simply return one
 749      * if it already exists.
 750      */
 751     if (self->phi_out) {
 752         *out = self->phi_out;
 753         return true;
 754     }
 755     return false;
 756 }