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, TYPE_##T);                  \
  36     ( (ast_node*)self )->node.destroy = (ast_node_delete*)destroyfn
  37
  38 /* It must not be possible to get here. */
  39 static GMQCC_NORETURN 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, int nodetype)
  47 {
  48     self->node.context = ctx;
  49     self->node.destroy = &_ast_node_destroy;
  50     self->node.keep    = false;
  51     self->node.nodetype = nodetype;
  52 }
  53
  54 /* General expression initialization */
  55 static void ast_expression_init(ast_expression *self,
  56                                 ast_expression_codegen *codegen)
  57 {
  58     self->expression.codegen = codegen;
  59     self->expression.vtype   = TYPE_VOID;
  60     self->expression.next    = NULL;
  61     MEM_VECTOR_INIT(&self->expression, params);
  62 }
  63
  64 static void ast_expression_delete(ast_expression *self)
  65 {
  66     size_t i;
  67     if (self->expression.next)
  68         ast_delete(self->expression.next);
  69     for (i = 0; i < self->expression.params_count; ++i) {
  70         ast_delete(self->expression.params[i]);
  71     }
  72     MEM_VECTOR_CLEAR(&self->expression, params);
  73 }
  74
  75 static void ast_expression_delete_full(ast_expression *self)
  76 {
  77     ast_expression_delete(self);
  78     mem_d(self);
  79 }
  80
  81 MEM_VEC_FUNCTIONS(ast_expression_common, ast_value*, params)
  82
  83 static ast_expression* ast_type_copy(lex_ctx ctx, const ast_expression *ex);
  84 static ast_value* ast_value_copy(const ast_value *self)
  85 {
  86     ast_value *cp = ast_value_new(self->expression.node.context, self->name, self->expression.vtype);
  87     if (self->expression.next) {
  88         cp->expression.next = ast_type_copy(self->expression.node.context, self->expression.next);
  89         if (!cp->expression.next) {
  90             ast_value_delete(cp);
  91             return NULL;
  92         }
  93     }
  94     return cp;
  95 }
  96
  97 static ast_expression* ast_type_copy(lex_ctx ctx, const ast_expression *ex)
  98 {
  99     size_t i;
 100     const ast_expression_common *fromex;
 101     ast_expression_common *selfex;
 102
 103     if (!ex)
 104         return NULL;
 105     else
 106     {
 107         ast_instantiate(ast_expression, ctx, ast_expression_delete_full);
 108
 109         fromex   = &ex->expression;
 110         selfex = &self->expression;
 111
 112         /* This may never be codegen()d */
 113         selfex->codegen = NULL;
 114
 115         selfex->vtype = fromex->vtype;
 116         if (fromex->next)
 117         {
 118             selfex->next = ast_type_copy(ctx, fromex->next);
 119             if (!selfex->next) {
 120                 ast_expression_delete_full(self);
 121                 return NULL;
 122             }
 123         }
 124         else
 125             selfex->next = NULL;
 126
 127         for (i = 0; i < fromex->params_count; ++i) {
 128             ast_value *v = ast_value_copy(fromex->params[i]);
 129             if (!v || !ast_expression_common_params_add(selfex, v)) {
 130                 ast_expression_delete_full(self);
 131                 return NULL;
 132             }
 133         }
 134
 135         return self;
 136     }
 137 }
 138
 139 ast_value* ast_value_new(lex_ctx ctx, const char *name, int t)
 140 {
 141     ast_instantiate(ast_value, ctx, ast_value_delete);
 142     ast_expression_init((ast_expression*)self,
 143                         (ast_expression_codegen*)&ast_value_codegen);
 144     self->expression.node.keep = true; /* keep */
 145
 146     self->name = name ? util_strdup(name) : NULL;
 147     self->expression.vtype = t;
 148     self->expression.next  = NULL;
 149     self->isconst = false;
 150     memset(&self->constval, 0, sizeof(self->constval));
 151
 152     self->ir_v    = NULL;
 153
 154     return self;
 155 }
 156
 157 void ast_value_delete(ast_value* self)
 158 {
 159     if (self->name)
 160         mem_d((void*)self->name);
 161     if (self->isconst) {
 162         switch (self->expression.vtype)
 163         {
 164         case TYPE_STRING:
 165             mem_d((void*)self->constval.vstring);
 166             break;
 167         case TYPE_FUNCTION:
 168             /* unlink us from the function node */
 169             self->constval.vfunc->vtype = NULL;
 170             break;
 171         /* NOTE: delete function? currently collected in
 172          * the parser structure
 173          */
 174         default:
 175             break;
 176         }
 177     }
 178     ast_expression_delete((ast_expression*)self);
 179     mem_d(self);
 180 }
 181
 182 bool GMQCC_WARN ast_value_params_add(ast_value *self, ast_value *p)
 183 {
 184     return ast_expression_common_params_add(&self->expression, p);
 185 }
 186
 187 bool ast_value_set_name(ast_value *self, const char *name)
 188 {
 189     if (self->name)
 190         mem_d((void*)self->name);
 191     self->name = util_strdup(name);
 192     return !!self->name;
 193 }
 194
 195 ast_binary* ast_binary_new(lex_ctx ctx, int op,
 196                            ast_expression* left, ast_expression* right)
 197 {
 198     ast_instantiate(ast_binary, ctx, ast_binary_delete);
 199     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_binary_codegen);
 200
 201     self->op = op;
 202     self->left = left;
 203     self->right = right;
 204
 205     return self;
 206 }
 207
 208 void ast_binary_delete(ast_binary *self)
 209 {
 210     ast_unref(self->left);
 211     ast_unref(self->right);
 212     ast_expression_delete((ast_expression*)self);
 213     mem_d(self);
 214 }
 215
 216 ast_unary* ast_unary_new(lex_ctx ctx, int op,
 217                          ast_expression *expr)
 218 {
 219     ast_instantiate(ast_unary, ctx, ast_unary_delete);
 220     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_unary_codegen);
 221
 222     self->op = op;
 223     self->operand = expr;
 224
 225     return self;
 226 }
 227
 228 void ast_unary_delete(ast_unary *self)
 229 {
 230     ast_unref(self->operand);
 231     ast_expression_delete((ast_expression*)self);
 232     mem_d(self);
 233 }
 234
 235 ast_return* ast_return_new(lex_ctx ctx, ast_expression *expr)
 236 {
 237     ast_instantiate(ast_return, ctx, ast_return_delete);
 238     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_return_codegen);
 239
 240     self->operand = expr;
 241
 242     return self;
 243 }
 244
 245 void ast_return_delete(ast_return *self)
 246 {
 247     ast_unref(self->operand);
 248     ast_expression_delete((ast_expression*)self);
 249     mem_d(self);
 250 }
 251
 252 ast_entfield* ast_entfield_new(lex_ctx ctx, ast_expression *entity, ast_expression *field)
 253 {
 254     const ast_expression *outtype;
 255
 256     ast_instantiate(ast_entfield, ctx, ast_entfield_delete);
 257
 258     if (field->expression.vtype != TYPE_FIELD) {
 259         mem_d(self);
 260         return NULL;
 261     }
 262
 263     outtype = field->expression.next;
 264     if (!outtype) {
 265         mem_d(self);
 266         /* Error: field has no type... */
 267         return NULL;
 268     }
 269
 270     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_entfield_codegen);
 271
 272     self->expression.vtype = outtype->expression.vtype;
 273     self->expression.next  = ast_type_copy(ctx, outtype->expression.next);
 274
 275     self->entity = entity;
 276     self->field  = field;
 277
 278     return self;
 279 }
 280
 281 void ast_entfield_delete(ast_entfield *self)
 282 {
 283     ast_unref(self->entity);
 284     ast_unref(self->field);
 285     ast_expression_delete((ast_expression*)self);
 286     mem_d(self);
 287 }
 288
 289 ast_ifthen* ast_ifthen_new(lex_ctx ctx, ast_expression *cond, ast_expression *ontrue, ast_expression *onfalse)
 290 {
 291     ast_instantiate(ast_ifthen, ctx, ast_ifthen_delete);
 292     if (!ontrue && !onfalse) {
 293         /* because it is invalid */
 294         mem_d(self);
 295         return NULL;
 296     }
 297     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_ifthen_codegen);
 298
 299     self->cond     = cond;
 300     self->on_true  = ontrue;
 301     self->on_false = onfalse;
 302
 303     return self;
 304 }
 305
 306 void ast_ifthen_delete(ast_ifthen *self)
 307 {
 308     ast_unref(self->cond);
 309     if (self->on_true)
 310         ast_unref(self->on_true);
 311     if (self->on_false)
 312         ast_unref(self->on_false);
 313     ast_expression_delete((ast_expression*)self);
 314     mem_d(self);
 315 }
 316
 317 ast_ternary* ast_ternary_new(lex_ctx ctx, ast_expression *cond, ast_expression *ontrue, ast_expression *onfalse)
 318 {
 319     ast_instantiate(ast_ternary, ctx, ast_ternary_delete);
 320     /* This time NEITHER must be NULL */
 321     if (!ontrue || !onfalse) {
 322         mem_d(self);
 323         return NULL;
 324     }
 325     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_ternary_codegen);
 326
 327     self->cond     = cond;
 328     self->on_true  = ontrue;
 329     self->on_false = onfalse;
 330     self->phi_out  = NULL;
 331
 332     return self;
 333 }
 334
 335 void ast_ternary_delete(ast_ternary *self)
 336 {
 337     ast_unref(self->cond);
 338     ast_unref(self->on_true);
 339     ast_unref(self->on_false);
 340     ast_expression_delete((ast_expression*)self);
 341     mem_d(self);
 342 }
 343
 344 ast_loop* ast_loop_new(lex_ctx ctx,
 345                        ast_expression *initexpr,
 346                        ast_expression *precond,
 347                        ast_expression *postcond,
 348                        ast_expression *increment,
 349                        ast_expression *body)
 350 {
 351     ast_instantiate(ast_loop, ctx, ast_loop_delete);
 352     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_loop_codegen);
 353
 354     self->initexpr  = initexpr;
 355     self->precond   = precond;
 356     self->postcond  = postcond;
 357     self->increment = increment;
 358     self->body      = body;
 359
 360     return self;
 361 }
 362
 363 void ast_loop_delete(ast_loop *self)
 364 {
 365     if (self->initexpr)
 366         ast_unref(self->initexpr);
 367     if (self->precond)
 368         ast_unref(self->precond);
 369     if (self->postcond)
 370         ast_unref(self->postcond);
 371     if (self->increment)
 372         ast_unref(self->increment);
 373     if (self->body)
 374         ast_unref(self->body);
 375     ast_expression_delete((ast_expression*)self);
 376     mem_d(self);
 377 }
 378
 379 ast_call* ast_call_new(lex_ctx ctx,
 380                        ast_expression *funcexpr)
 381 {
 382     ast_instantiate(ast_call, ctx, ast_call_delete);
 383     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_call_codegen);
 384
 385     MEM_VECTOR_INIT(self, params);
 386
 387     self->func = funcexpr;
 388
 389     return self;
 390 }
 391 MEM_VEC_FUNCTIONS(ast_call, ast_expression*, params)
 392
 393 void ast_call_delete(ast_call *self)
 394 {
 395     size_t i;
 396     for (i = 0; i < self->params_count; ++i)
 397         ast_unref(self->params[i]);
 398     MEM_VECTOR_CLEAR(self, params);
 399
 400     if (self->func)
 401         ast_unref(self->func);
 402
 403     ast_expression_delete((ast_expression*)self);
 404     mem_d(self);
 405 }
 406
 407 ast_store* ast_store_new(lex_ctx ctx, int op,
 408                          ast_expression *dest, ast_expression *source)
 409 {
 410     ast_instantiate(ast_store, ctx, ast_store_delete);
 411     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_store_codegen);
 412
 413     self->op = op;
 414     self->dest = dest;
 415     self->source = source;
 416
 417     return self;
 418 }
 419
 420 void ast_store_delete(ast_store *self)
 421 {
 422     ast_unref(self->dest);
 423     ast_unref(self->source);
 424     ast_expression_delete((ast_expression*)self);
 425     mem_d(self);
 426 }
 427
 428 ast_block* ast_block_new(lex_ctx ctx)
 429 {
 430     ast_instantiate(ast_block, ctx, ast_block_delete);
 431     ast_expression_init((ast_expression*)self,
 432                         (ast_expression_codegen*)&ast_block_codegen);
 433
 434     MEM_VECTOR_INIT(self, locals);
 435     MEM_VECTOR_INIT(self, exprs);
 436
 437     return self;
 438 }
 439 MEM_VEC_FUNCTIONS(ast_block, ast_value*, locals)
 440 MEM_VEC_FUNCTIONS(ast_block, ast_expression*, exprs)
 441
 442 void ast_block_delete(ast_block *self)
 443 {
 444     size_t i;
 445     for (i = 0; i < self->exprs_count; ++i)
 446         ast_unref(self->exprs[i]);
 447     MEM_VECTOR_CLEAR(self, exprs);
 448     for (i = 0; i < self->locals_count; ++i)
 449         ast_delete(self->locals[i]);
 450     MEM_VECTOR_CLEAR(self, locals);
 451     ast_expression_delete((ast_expression*)self);
 452     mem_d(self);
 453 }
 454
 455 bool ast_block_set_type(ast_block *self, ast_expression *from)
 456 {
 457     if (self->expression.next)
 458         ast_delete(self->expression.next);
 459     self->expression.vtype = from->expression.vtype;
 460     if (from->expression.next) {
 461         self->expression.next = ast_type_copy(self->expression.node.context, from->expression.next);
 462         if (!self->expression.next)
 463             return false;
 464     }
 465     return true;
 466 }
 467
 468 ast_function* ast_function_new(lex_ctx ctx, const char *name, ast_value *vtype)
 469 {
 470     ast_instantiate(ast_function, ctx, ast_function_delete);
 471
 472     if (!vtype ||
 473         vtype->isconst ||
 474         vtype->expression.vtype != TYPE_FUNCTION)
 475     {
 476         mem_d(self);
 477         return NULL;
 478     }
 479
 480     self->vtype = vtype;
 481     self->name = name ? util_strdup(name) : NULL;
 482     MEM_VECTOR_INIT(self, blocks);
 483
 484     self->labelcount = 0;
 485     self->builtin = 0;
 486
 487     self->ir_func = NULL;
 488     self->curblock = NULL;
 489
 490     self->breakblock    = NULL;
 491     self->continueblock = NULL;
 492
 493     vtype->isconst = true;
 494     vtype->constval.vfunc = self;
 495
 496     return self;
 497 }
 498
 499 MEM_VEC_FUNCTIONS(ast_function, ast_block*, blocks)
 500
 501 void ast_function_delete(ast_function *self)
 502 {
 503     size_t i;
 504     if (self->name)
 505         mem_d((void*)self->name);
 506     if (self->vtype) {
 507         /* ast_value_delete(self->vtype); */
 508         self->vtype->isconst = false;
 509         self->vtype->constval.vfunc = NULL;
 510         /* We use unref - if it was stored in a global table it is supposed
 511          * to be deleted from *there*
 512          */
 513         ast_unref(self->vtype);
 514     }
 515     for (i = 0; i < self->blocks_count; ++i)
 516         ast_delete(self->blocks[i]);
 517     MEM_VECTOR_CLEAR(self, blocks);
 518     mem_d(self);
 519 }
 520
 521 static void ast_util_hexitoa(char *buf, size_t size, unsigned int num)
 522 {
 523     unsigned int base = 10;
 524 #define checknul() do { if (size == 1) { *buf = 0; return; } } while (0)
 525 #define addch(x) do { *buf++ = (x); --size; checknul(); } while (0)
 526     if (size < 1)
 527         return;
 528     checknul();
 529     if (!num)
 530         addch('0');
 531     else {
 532         while (num)
 533         {
 534             int digit = num % base;
 535             num /= base;
 536             addch('0' + digit);
 537         }
 538     }
 539
 540     *buf = 0;
 541 #undef addch
 542 #undef checknul
 543 }
 544
 545 const char* ast_function_label(ast_function *self, const char *prefix)
 546 {
 547     size_t id = (self->labelcount++);
 548     size_t len = strlen(prefix);
 549     strncpy(self->labelbuf, prefix, sizeof(self->labelbuf));
 550     ast_util_hexitoa(self->labelbuf + len, sizeof(self->labelbuf)-len, id);
 551     return self->labelbuf;
 552 }
 553
 554 /*********************************************************************/
 555 /* AST codegen part
 556  * by convention you must never pass NULL to the 'ir_value **out'
 557  * parameter. If you really don't care about the output, pass a dummy.
 558  * But I can't imagine a pituation where the output is truly unnecessary.
 559  */
 560
 561 bool ast_value_codegen(ast_value *self, ast_function *func, bool lvalue, ir_value **out)
 562 {
 563     /* NOTE: This is the codegen for a variable used in an expression.
 564      * It is not the codegen to generate the value. For this purpose,
 565      * ast_local_codegen and ast_global_codegen are to be used before this
 566      * is executed. ast_function_codegen should take care of its locals,
 567      * and the ast-user should take care of ast_global_codegen to be used
 568      * on all the globals.
 569      */
 570     if (!self->ir_v) {
 571         printf("ast_value used before generated (%s)\n", self->name);
 572         return false;
 573     }
 574     *out = self->ir_v;
 575     return true;
 576 }
 577
 578 bool ast_global_codegen(ast_value *self, ir_builder *ir)
 579 {
 580     ir_value *v = NULL;
 581     if (self->isconst && self->expression.vtype == TYPE_FUNCTION)
 582     {
 583         ir_function *func = ir_builder_create_function(ir, self->name, self->expression.next->expression.vtype);
 584         if (!func)
 585             return false;
 586
 587         self->constval.vfunc->ir_func = func;
 588         self->ir_v = func->value;
 589         /* The function is filled later on ast_function_codegen... */
 590         return true;
 591     }
 592
 593     v = ir_builder_create_global(ir, self->name, self->expression.vtype);
 594     if (!v)
 595         return false;
 596
 597     if (self->isconst) {
 598         switch (self->expression.vtype)
 599         {
 600             case TYPE_FLOAT:
 601                 if (!ir_value_set_float(v, self->constval.vfloat))
 602                     goto error;
 603                 break;
 604             case TYPE_VECTOR:
 605                 if (!ir_value_set_vector(v, self->constval.vvec))
 606                     goto error;
 607                 break;
 608             case TYPE_STRING:
 609                 if (!ir_value_set_string(v, self->constval.vstring))
 610                     goto error;
 611                 break;
 612             case TYPE_FUNCTION:
 613                 printf("global of type function not properly generated\n");
 614                 goto error;
 615                 /* Cannot generate an IR value for a function,
 616                  * need a pointer pointing to a function rather.
 617                  */
 618             default:
 619                 printf("TODO: global constant type %i\n", self->expression.vtype);
 620                 break;
 621         }
 622     }
 623
 624     /* link us to the ir_value */
 625     self->ir_v = v;
 626     return true;
 627
 628 error: /* clean up */
 629     ir_value_delete(v);
 630     return false;
 631 }
 632
 633 bool ast_local_codegen(ast_value *self, ir_function *func, bool param)
 634 {
 635     ir_value *v = NULL;
 636     if (self->isconst && self->expression.vtype == TYPE_FUNCTION)
 637     {
 638         /* Do we allow local functions? I think not...
 639          * this is NOT a function pointer atm.
 640          */
 641         return false;
 642     }
 643
 644     v = ir_function_create_local(func, self->name, self->expression.vtype, param);
 645     if (!v)
 646         return false;
 647
 648     /* A constant local... hmmm...
 649      * I suppose the IR will have to deal with this
 650      */
 651     if (self->isconst) {
 652         switch (self->expression.vtype)
 653         {
 654             case TYPE_FLOAT:
 655                 if (!ir_value_set_float(v, self->constval.vfloat))
 656                     goto error;
 657                 break;
 658             case TYPE_VECTOR:
 659                 if (!ir_value_set_vector(v, self->constval.vvec))
 660                     goto error;
 661                 break;
 662             case TYPE_STRING:
 663                 if (!ir_value_set_string(v, self->constval.vstring))
 664                     goto error;
 665                 break;
 666             default:
 667                 printf("TODO: global constant type %i\n", self->expression.vtype);
 668                 break;
 669         }
 670     }
 671
 672     /* link us to the ir_value */
 673     self->ir_v = v;
 674     return true;
 675
 676 error: /* clean up */
 677     ir_value_delete(v);
 678     return false;
 679 }
 680
 681 bool ast_function_codegen(ast_function *self, ir_builder *ir)
 682 {
 683     ir_function *irf;
 684     ir_value    *dummy;
 685     ast_expression_common *ec;
 686     size_t    i;
 687
 688     irf = self->ir_func;
 689     if (!irf) {
 690         printf("ast_function's related ast_value was not generated yet\n");
 691         return false;
 692     }
 693
 694     /* fill the parameter list */
 695     ec = &self->vtype->expression;
 696     for (i = 0; i < ec->params_count; ++i)
 697     {
 698         if (!ir_function_params_add(irf, ec->params[i]->expression.vtype))
 699             return false;
 700         if (!self->builtin) {
 701             if (!ast_local_codegen(ec->params[i], self->ir_func, true))
 702                 return false;
 703         }
 704     }
 705
 706     if (self->builtin) {
 707         irf->builtin = self->builtin;
 708         return true;
 709     }
 710
 711     self->curblock = ir_function_create_block(irf, "entry");
 712     if (!self->curblock)
 713         return false;
 714
 715     for (i = 0; i < self->blocks_count; ++i) {
 716         ast_expression_codegen *gen = self->blocks[i]->expression.codegen;
 717         if (!(*gen)((ast_expression*)self->blocks[i], self, false, &dummy))
 718             return false;
 719     }
 720
 721     /* TODO: check return types */
 722     if (!self->curblock->is_return)
 723     {
 724         if (!self->vtype->expression.next ||
 725             self->vtype->expression.next->expression.vtype == TYPE_VOID)
 726         {
 727             return ir_block_create_return(self->curblock, NULL);
 728         }
 729         else
 730         {
 731             /* error("missing return"); */
 732             return false;
 733         }
 734     }
 735     return true;
 736 }
 737
 738 /* Note, you will not see ast_block_codegen generate ir_blocks.
 739  * To the AST and the IR, blocks are 2 different things.
 740  * In the AST it represents a block of code, usually enclosed in
 741  * curly braces {...}.
 742  * While in the IR it represents a block in terms of control-flow.
 743  */
 744 bool ast_block_codegen(ast_block *self, ast_function *func, bool lvalue, ir_value **out)
 745 {
 746     size_t i;
 747
 748     /* We don't use this
 749      * Note: an ast-representation using the comma-operator
 750      * of the form: (a, b, c) = x should not assign to c...
 751      */
 752     (void)lvalue;
 753
 754     /* output is NULL at first, we'll have each expression
 755      * assign to out output, thus, a comma-operator represention
 756      * using an ast_block will return the last generated value,
 757      * so: (b, c) + a  executed both b and c, and returns c,
 758      * which is then added to a.
 759      */
 760     *out = NULL;
 761
 762     /* generate locals */
 763     for (i = 0; i < self->locals_count; ++i)
 764     {
 765         if (!ast_local_codegen(self->locals[i], func->ir_func, false))
 766             return false;
 767     }
 768
 769     for (i = 0; i < self->exprs_count; ++i)
 770     {
 771         ast_expression_codegen *gen = self->exprs[i]->expression.codegen;
 772         if (!(*gen)(self->exprs[i], func, false, out))
 773             return false;
 774     }
 775
 776     return true;
 777 }
 778
 779 bool ast_store_codegen(ast_store *self, ast_function *func, bool lvalue, ir_value **out)
 780 {
 781     ast_expression_codegen *cgen;
 782     ir_value *left, *right;
 783
 784     cgen = self->dest->expression.codegen;
 785     /* lvalue! */
 786     if (!(*cgen)((ast_expression*)(self->dest), func, true, &left))
 787         return false;
 788
 789     cgen = self->source->expression.codegen;
 790     /* rvalue! */
 791     if (!(*cgen)((ast_expression*)(self->source), func, false, &right))
 792         return false;
 793
 794     if (!ir_block_create_store_op(func->curblock, self->op, left, right))
 795         return false;
 796
 797     /* Theoretically, an assinment returns its left side as an
 798      * lvalue, if we don't need an lvalue though, we return
 799      * the right side as an rvalue, otherwise we have to
 800      * somehow know whether or not we need to dereference the pointer
 801      * on the left side - that is: OP_LOAD if it was an address.
 802      * Also: in original QC we cannot OP_LOADP *anyway*.
 803      */
 804     *out = (lvalue ? left : right);
 805
 806     return true;
 807 }
 808
 809 bool ast_binary_codegen(ast_binary *self, ast_function *func, bool lvalue, ir_value **out)
 810 {
 811     ast_expression_codegen *cgen;
 812     ir_value *left, *right;
 813
 814     /* In the context of a binary operation, we can disregard
 815      * the lvalue flag.
 816      */
 817      (void)lvalue;
 818
 819     cgen = self->left->expression.codegen;
 820     /* lvalue! */
 821     if (!(*cgen)((ast_expression*)(self->left), func, false, &left))
 822         return false;
 823
 824     cgen = self->right->expression.codegen;
 825     /* rvalue! */
 826     if (!(*cgen)((ast_expression*)(self->right), func, false, &right))
 827         return false;
 828
 829     *out = ir_block_create_binop(func->curblock, ast_function_label(func, "bin"),
 830                                  self->op, left, right);
 831     if (!*out)
 832         return false;
 833
 834     return true;
 835 }
 836
 837 bool ast_unary_codegen(ast_unary *self, ast_function *func, bool lvalue, ir_value **out)
 838 {
 839     ast_expression_codegen *cgen;
 840     ir_value *operand;
 841
 842     /* In the context of a unary operation, we can disregard
 843      * the lvalue flag.
 844      */
 845     (void)lvalue;
 846
 847     cgen = self->operand->expression.codegen;
 848     /* lvalue! */
 849     if (!(*cgen)((ast_expression*)(self->operand), func, false, &operand))
 850         return false;
 851
 852     *out = ir_block_create_unary(func->curblock, ast_function_label(func, "unary"),
 853                                  self->op, operand);
 854     if (!*out)
 855         return false;
 856
 857     return true;
 858 }
 859
 860 bool ast_return_codegen(ast_return *self, ast_function *func, bool lvalue, ir_value **out)
 861 {
 862     ast_expression_codegen *cgen;
 863     ir_value *operand;
 864
 865     /* In the context of a return operation, we can disregard
 866      * the lvalue flag.
 867      */
 868     (void)lvalue;
 869
 870     cgen = self->operand->expression.codegen;
 871     /* lvalue! */
 872     if (!(*cgen)((ast_expression*)(self->operand), func, false, &operand))
 873         return false;
 874
 875     if (!ir_block_create_return(func->curblock, operand))
 876         return false;
 877
 878     return true;
 879 }
 880
 881 bool ast_entfield_codegen(ast_entfield *self, ast_function *func, bool lvalue, ir_value **out)
 882 {
 883     ast_expression_codegen *cgen;
 884     ir_value *ent, *field;
 885
 886     /* This function needs to take the 'lvalue' flag into account!
 887      * As lvalue we provide a field-pointer, as rvalue we provide the
 888      * value in a temp.
 889      */
 890
 891     cgen = self->entity->expression.codegen;
 892     if (!(*cgen)((ast_expression*)(self->entity), func, false, &ent))
 893         return false;
 894
 895     cgen = self->field->expression.codegen;
 896     if (!(*cgen)((ast_expression*)(self->field), func, false, &field))
 897         return false;
 898
 899     if (lvalue) {
 900         /* address! */
 901         *out = ir_block_create_fieldaddress(func->curblock, ast_function_label(func, "efa"),
 902                                             ent, field);
 903     } else {
 904         *out = ir_block_create_load_from_ent(func->curblock, ast_function_label(func, "efv"),
 905                                              ent, field, self->expression.vtype);
 906     }
 907     if (!*out)
 908         return false;
 909
 910     /* Hm that should be it... */
 911     return true;
 912 }
 913
 914 bool ast_ifthen_codegen(ast_ifthen *self, ast_function *func, bool lvalue, ir_value **out)
 915 {
 916     ast_expression_codegen *cgen;
 917
 918     ir_value *condval;
 919     ir_value *dummy;
 920
 921     ir_block *cond = func->curblock;
 922     ir_block *ontrue;
 923     ir_block *onfalse;
 924     ir_block *merge;
 925
 926     /* We don't output any value, thus also don't care about r/lvalue */
 927     (void)out;
 928     (void)lvalue;
 929
 930     /* generate the condition */
 931     func->curblock = cond;
 932     cgen = self->cond->expression.codegen;
 933     if (!(*cgen)((ast_expression*)(self->cond), func, false, &condval))
 934         return false;
 935
 936     /* on-true path */
 937
 938     if (self->on_true) {
 939         /* create on-true block */
 940         ontrue = ir_function_create_block(func->ir_func, ast_function_label(func, "ontrue"));
 941         if (!ontrue)
 942             return false;
 943
 944         /* enter the block */
 945         func->curblock = ontrue;
 946
 947         /* generate */
 948         cgen = self->on_true->expression.codegen;
 949         if (!(*cgen)((ast_expression*)(self->on_true), func, false, &dummy))
 950             return false;
 951     } else
 952         ontrue = NULL;
 953
 954     /* on-false path */
 955     if (self->on_false) {
 956         /* create on-false block */
 957         onfalse = ir_function_create_block(func->ir_func, ast_function_label(func, "onfalse"));
 958         if (!onfalse)
 959             return false;
 960
 961         /* enter the block */
 962         func->curblock = onfalse;
 963
 964         /* generate */
 965         cgen = self->on_false->expression.codegen;
 966         if (!(*cgen)((ast_expression*)(self->on_false), func, false, &dummy))
 967             return false;
 968     } else
 969         onfalse = NULL;
 970
 971     /* Merge block were they all merge in to */
 972     merge = ir_function_create_block(func->ir_func, ast_function_label(func, "endif"));
 973     if (!merge)
 974         return false;
 975
 976     /* add jumps ot the merge block */
 977     if (ontrue && !ir_block_create_jump(ontrue, merge))
 978         return false;
 979     if (onfalse && !ir_block_create_jump(onfalse, merge))
 980         return false;
 981
 982     /* we create the if here, that way all blocks are ordered :)
 983      */
 984     if (!ir_block_create_if(cond, condval,
 985                             (ontrue  ? ontrue  : merge),
 986                             (onfalse ? onfalse : merge)))
 987     {
 988         return false;
 989     }
 990
 991     /* Now enter the merge block */
 992     func->curblock = merge;
 993
 994     return true;
 995 }
 996
 997 bool ast_ternary_codegen(ast_ternary *self, ast_function *func, bool lvalue, ir_value **out)
 998 {
 999     ast_expression_codegen *cgen;
1000
1001     ir_value *condval;
1002     ir_value *trueval, *falseval;
1003     ir_instr *phi;
1004
1005     ir_block *cond = func->curblock;
1006     ir_block *ontrue;
1007     ir_block *onfalse;
1008     ir_block *merge;
1009
1010     /* In theory it shouldn't be possible to pass through a node twice, but
1011      * in case we add any kind of optimization pass for the AST itself, it
1012      * may still happen, thus we remember a created ir_value and simply return one
1013      * if it already exists.
1014      */
1015     if (self->phi_out) {
1016         *out = self->phi_out;
1017         return true;
1018     }
1019
1020     /* Ternary can never create an lvalue... */
1021     if (lvalue)
1022         return false;
1023
1024     /* In the following, contraty to ast_ifthen, we assume both paths exist. */
1025
1026     /* generate the condition */
1027     func->curblock = cond;
1028     cgen = self->cond->expression.codegen;
1029     if (!(*cgen)((ast_expression*)(self->cond), func, false, &condval))
1030         return false;
1031
1032     /* create on-true block */
1033     ontrue = ir_function_create_block(func->ir_func, ast_function_label(func, "tern_T"));
1034     if (!ontrue)
1035         return false;
1036     else
1037     {
1038         /* enter the block */
1039         func->curblock = ontrue;
1040
1041         /* generate */
1042         cgen = self->on_true->expression.codegen;
1043         if (!(*cgen)((ast_expression*)(self->on_true), func, false, &trueval))
1044             return false;
1045     }
1046
1047     /* create on-false block */
1048     onfalse = ir_function_create_block(func->ir_func, ast_function_label(func, "tern_F"));
1049     if (!onfalse)
1050         return false;
1051     else
1052     {
1053         /* enter the block */
1054         func->curblock = onfalse;
1055
1056         /* generate */
1057         cgen = self->on_false->expression.codegen;
1058         if (!(*cgen)((ast_expression*)(self->on_false), func, false, &falseval))
1059             return false;
1060     }
1061
1062     /* create merge block */
1063     merge = ir_function_create_block(func->ir_func, ast_function_label(func, "tern_out"));
1064     if (!merge)
1065         return false;
1066     /* jump to merge block */
1067     if (!ir_block_create_jump(ontrue, merge))
1068         return false;
1069     if (!ir_block_create_jump(onfalse, merge))
1070         return false;
1071
1072     /* create if instruction */
1073     if (!ir_block_create_if(cond, condval, ontrue, onfalse))
1074         return false;
1075
1076     /* Now enter the merge block */
1077     func->curblock = merge;
1078
1079     /* Here, now, we need a PHI node
1080      * but first some sanity checking...
1081      */
1082     if (trueval->vtype != falseval->vtype) {
1083         /* error("ternary with different types on the two sides"); */
1084         return false;
1085     }
1086
1087     /* create PHI */
1088     phi = ir_block_create_phi(merge, ast_function_label(func, "phi"), trueval->vtype);
1089     if (!phi ||
1090         !ir_phi_add(phi, ontrue,  trueval) ||
1091         !ir_phi_add(phi, onfalse, falseval))
1092     {
1093         return false;
1094     }
1095
1096     self->phi_out = ir_phi_value(phi);
1097     *out = self->phi_out;
1098
1099     return true;
1100 }
1101
1102 bool ast_loop_codegen(ast_loop *self, ast_function *func, bool lvalue, ir_value **out)
1103 {
1104     ast_expression_codegen *cgen;
1105
1106     ir_value *dummy      = NULL;
1107     ir_value *precond    = NULL;
1108     ir_value *postcond   = NULL;
1109
1110     /* Since we insert some jumps "late" so we have blocks
1111      * ordered "nicely", we need to keep track of the actual end-blocks
1112      * of expressions to add the jumps to.
1113      */
1114     ir_block *bbody      = NULL, *end_bbody      = NULL;
1115     ir_block *bprecond   = NULL, *end_bprecond   = NULL;
1116     ir_block *bpostcond  = NULL, *end_bpostcond  = NULL;
1117     ir_block *bincrement = NULL, *end_bincrement = NULL;
1118     ir_block *bout       = NULL, *bin            = NULL;
1119
1120     /* let's at least move the outgoing block to the end */
1121     size_t    bout_id;
1122
1123     /* 'break' and 'continue' need to be able to find the right blocks */
1124     ir_block *bcontinue     = NULL;
1125     ir_block *bbreak        = NULL;
1126
1127     ir_block *old_bcontinue = NULL;
1128     ir_block *old_bbreak    = NULL;
1129
1130     ir_block *tmpblock      = NULL;
1131
1132     (void)lvalue;
1133     (void)out;
1134
1135     /* NOTE:
1136      * Should we ever need some kind of block ordering, better make this function
1137      * move blocks around than write a block ordering algorithm later... after all
1138      * the ast and ir should work together, not against each other.
1139      */
1140
1141     /* initexpr doesn't get its own block, it's pointless, it could create more blocks
1142      * anyway if for example it contains a ternary.
1143      */
1144     if (self->initexpr)
1145     {
1146         cgen = self->initexpr->expression.codegen;
1147         if (!(*cgen)((ast_expression*)(self->initexpr), func, false, &dummy))
1148             return false;
1149     }
1150
1151     /* Store the block from which we enter this chaos */
1152     bin = func->curblock;
1153
1154     /* The pre-loop condition needs its own block since we
1155      * need to be able to jump to the start of that expression.
1156      */
1157     if (self->precond)
1158     {
1159         bprecond = ir_function_create_block(func->ir_func, ast_function_label(func, "pre_loop_cond"));
1160         if (!bprecond)
1161             return false;
1162
1163         /* the pre-loop-condition the least important place to 'continue' at */
1164         bcontinue = bprecond;
1165
1166         /* enter */
1167         func->curblock = bprecond;
1168
1169         /* generate */
1170         cgen = self->precond->expression.codegen;
1171         if (!(*cgen)((ast_expression*)(self->precond), func, false, &precond))
1172             return false;
1173
1174         end_bprecond = func->curblock;
1175     } else {
1176         bprecond = end_bprecond = NULL;
1177     }
1178
1179     /* Now the next blocks won't be ordered nicely, but we need to
1180      * generate them this early for 'break' and 'continue'.
1181      */
1182     if (self->increment) {
1183         bincrement = ir_function_create_block(func->ir_func, ast_function_label(func, "loop_increment"));
1184         if (!bincrement)
1185             return false;
1186         bcontinue = bincrement; /* increment comes before the pre-loop-condition */
1187     } else {
1188         bincrement = end_bincrement = NULL;
1189     }
1190
1191     if (self->postcond) {
1192         bpostcond = ir_function_create_block(func->ir_func, ast_function_label(func, "post_loop_cond"));
1193         if (!bpostcond)
1194             return false;
1195         bcontinue = bpostcond; /* postcond comes before the increment */
1196     } else {
1197         bpostcond = end_bpostcond = NULL;
1198     }
1199
1200     bout_id = func->ir_func->blocks_count;
1201     bout = ir_function_create_block(func->ir_func, ast_function_label(func, "after_loop"));
1202     if (!bout)
1203         return false;
1204     bbreak = bout;
1205
1206     /* The loop body... */
1207     if (self->body)
1208     {
1209         bbody = ir_function_create_block(func->ir_func, ast_function_label(func, "loop_body"));
1210         if (!bbody)
1211             return false;
1212
1213         /* enter */
1214         func->curblock = bbody;
1215
1216         old_bbreak          = func->breakblock;
1217         old_bcontinue       = func->continueblock;
1218         func->breakblock    = bbreak;
1219         func->continueblock = bcontinue;
1220
1221         /* generate */
1222         cgen = self->body->expression.codegen;
1223         if (!(*cgen)((ast_expression*)(self->body), func, false, &dummy))
1224             return false;
1225
1226         end_bbody = func->curblock;
1227         func->breakblock    = old_bbreak;
1228         func->continueblock = old_bcontinue;
1229     }
1230
1231     /* post-loop-condition */
1232     if (self->postcond)
1233     {
1234         /* enter */
1235         func->curblock = bpostcond;
1236
1237         /* generate */
1238         cgen = self->postcond->expression.codegen;
1239         if (!(*cgen)((ast_expression*)(self->postcond), func, false, &postcond))
1240             return false;
1241
1242         end_bpostcond = func->curblock;
1243     }
1244
1245     /* The incrementor */
1246     if (self->increment)
1247     {
1248         /* enter */
1249         func->curblock = bincrement;
1250
1251         /* generate */
1252         cgen = self->increment->expression.codegen;
1253         if (!(*cgen)((ast_expression*)(self->increment), func, false, &dummy))
1254             return false;
1255
1256         end_bincrement = func->curblock;
1257     }
1258
1259     /* In any case now, we continue from the outgoing block */
1260     func->curblock = bout;
1261
1262     /* Now all blocks are in place */
1263     /* From 'bin' we jump to whatever comes first */
1264     if      (bprecond)   tmpblock = bprecond;
1265     else if (bbody)      tmpblock = bbody;
1266     else if (bpostcond)  tmpblock = bpostcond;
1267     else                 tmpblock = bout;
1268     if (!ir_block_create_jump(bin, tmpblock))
1269         return false;
1270
1271     /* From precond */
1272     if (bprecond)
1273     {
1274         ir_block *ontrue, *onfalse;
1275         if      (bbody)      ontrue = bbody;
1276         else if (bincrement) ontrue = bincrement;
1277         else if (bpostcond)  ontrue = bpostcond;
1278         else                 ontrue = bprecond;
1279         onfalse = bout;
1280         if (!ir_block_create_if(end_bprecond, precond, ontrue, onfalse))
1281             return false;
1282     }
1283
1284     /* from body */
1285     if (bbody)
1286     {
1287         if      (bincrement) tmpblock = bincrement;
1288         else if (bpostcond)  tmpblock = bpostcond;
1289         else if (bprecond)   tmpblock = bprecond;
1290         else                 tmpblock = bout;
1291         if (!ir_block_create_jump(end_bbody, tmpblock))
1292             return false;
1293     }
1294
1295     /* from increment */
1296     if (bincrement)
1297     {
1298         if      (bpostcond)  tmpblock = bpostcond;
1299         else if (bprecond)   tmpblock = bprecond;
1300         else if (bbody)      tmpblock = bbody;
1301         else                 tmpblock = bout;
1302         if (!ir_block_create_jump(end_bincrement, tmpblock))
1303             return false;
1304     }
1305
1306     /* from postcond */
1307     if (bpostcond)
1308     {
1309         ir_block *ontrue, *onfalse;
1310         if      (bprecond)   ontrue = bprecond;
1311         else if (bbody)      ontrue = bbody;
1312         else if (bincrement) ontrue = bincrement;
1313         else                 ontrue = bpostcond;
1314         onfalse = bout;
1315         if (!ir_block_create_if(end_bpostcond, postcond, ontrue, onfalse))
1316             return false;
1317     }
1318
1319     /* Move 'bout' to the end */
1320     if (!ir_function_blocks_remove(func->ir_func, bout_id) ||
1321         !ir_function_blocks_add(func->ir_func, bout))
1322     {
1323         ir_block_delete(bout);
1324         return false;
1325     }
1326
1327     return true;
1328 }
1329
1330 bool ast_call_codegen(ast_call *self, ast_function *func, bool lvalue, ir_value **out)
1331 {
1332     ast_expression_codegen *cgen;
1333     ir_value_vector         params;
1334     ir_instr               *callinstr;
1335     size_t i;
1336
1337     ir_value *funval = NULL;
1338
1339     /* return values are never rvalues */
1340     (void)lvalue;
1341
1342     cgen = self->func->expression.codegen;
1343     if (!(*cgen)((ast_expression*)(self->func), func, false, &funval))
1344         return false;
1345     if (!funval)
1346         return false;
1347
1348     MEM_VECTOR_INIT(&params, v);
1349
1350     /* parameters */
1351     for (i = 0; i < self->params_count; ++i)
1352     {
1353         ir_value *param;
1354         ast_expression *expr = self->params[i];
1355
1356         cgen = expr->expression.codegen;
1357         if (!(*cgen)(expr, func, false, &param))
1358             goto error;
1359         if (!param)
1360             goto error;
1361         if (!ir_value_vector_v_add(&params, param))
1362             goto error;
1363     }
1364
1365     callinstr = ir_block_create_call(func->curblock, ast_function_label(func, "call"), funval);
1366     if (!callinstr)
1367         goto error;
1368
1369     for (i = 0; i < params.v_count; ++i) {
1370         if (!ir_call_param(callinstr, params.v[i]))
1371             goto error;
1372     }
1373
1374     *out = ir_call_value(callinstr);
1375
1376     MEM_VECTOR_CLEAR(&params, v);
1377     return true;
1378 error:
1379     MEM_VECTOR_CLEAR(&params, v);
1380     return false;
1381 }