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 /* error handling */
  39 static void asterror(lex_ctx ctx, const char *msg, ...)
  40 {
  41     va_list ap;
  42     va_start(ap, msg);
  43     cvprintmsg(ctx, LVL_ERROR, "error", msg, ap);
  44     va_end(ap);
  45 }
  46
  47 /* It must not be possible to get here. */
  48 static GMQCC_NORETURN void _ast_node_destroy(ast_node *self)
  49 {
  50     fprintf(stderr, "ast node missing destroy()\n");
  51     abort();
  52 }
  53
  54 /* Initialize main ast node aprts */
  55 static void ast_node_init(ast_node *self, lex_ctx ctx, int nodetype)
  56 {
  57     self->node.context = ctx;
  58     self->node.destroy = &_ast_node_destroy;
  59     self->node.keep    = false;
  60     self->node.nodetype = nodetype;
  61 }
  62
  63 /* General expression initialization */
  64 static void ast_expression_init(ast_expression *self,
  65                                 ast_expression_codegen *codegen)
  66 {
  67     self->expression.codegen = codegen;
  68     self->expression.vtype   = TYPE_VOID;
  69     self->expression.next    = NULL;
  70     self->expression.outl    = NULL;
  71     self->expression.outr    = NULL;
  72     MEM_VECTOR_INIT(&self->expression, params);
  73 }
  74
  75 static void ast_expression_delete(ast_expression *self)
  76 {
  77     size_t i;
  78     if (self->expression.next)
  79         ast_delete(self->expression.next);
  80     for (i = 0; i < self->expression.params_count; ++i) {
  81         ast_delete(self->expression.params[i]);
  82     }
  83     MEM_VECTOR_CLEAR(&self->expression, params);
  84 }
  85
  86 static void ast_expression_delete_full(ast_expression *self)
  87 {
  88     ast_expression_delete(self);
  89     mem_d(self);
  90 }
  91
  92 MEM_VEC_FUNCTIONS(ast_expression_common, ast_value*, params)
  93
  94 static ast_expression* ast_type_copy(lex_ctx ctx, const ast_expression *ex);
  95 ast_value* ast_value_copy(const ast_value *self)
  96 {
  97     size_t i;
  98     const ast_expression_common *fromex;
  99     ast_expression_common *selfex;
 100     ast_value *cp = ast_value_new(self->expression.node.context, self->name, self->expression.vtype);
 101     if (self->expression.next) {
 102         cp->expression.next = ast_type_copy(self->expression.node.context, self->expression.next);
 103         if (!cp->expression.next) {
 104             ast_value_delete(cp);
 105             return NULL;
 106         }
 107     }
 108     fromex   = &self->expression;
 109     selfex = &cp->expression;
 110     for (i = 0; i < fromex->params_count; ++i) {
 111         ast_value *v = ast_value_copy(fromex->params[i]);
 112         if (!v || !ast_expression_common_params_add(selfex, v)) {
 113             ast_value_delete(cp);
 114             return NULL;
 115         }
 116     }
 117     return cp;
 118 }
 119
 120 static ast_expression* ast_shallow_type(lex_ctx ctx, int vtype)
 121 {
 122     ast_instantiate(ast_expression, ctx, ast_expression_delete_full);
 123     ast_expression_init(self, NULL);
 124     self->expression.codegen = NULL;
 125     self->expression.next    = NULL;
 126     self->expression.vtype   = vtype;
 127     return self;
 128 }
 129
 130 static ast_expression* ast_type_copy(lex_ctx ctx, const ast_expression *ex)
 131 {
 132     size_t i;
 133     const ast_expression_common *fromex;
 134     ast_expression_common *selfex;
 135
 136     if (!ex)
 137         return NULL;
 138     else
 139     {
 140         ast_instantiate(ast_expression, ctx, ast_expression_delete_full);
 141         ast_expression_init(self, NULL);
 142
 143         fromex   = &ex->expression;
 144         selfex = &self->expression;
 145
 146         /* This may never be codegen()d */
 147         selfex->codegen = NULL;
 148
 149         selfex->vtype = fromex->vtype;
 150         if (fromex->next)
 151         {
 152             selfex->next = ast_type_copy(ctx, fromex->next);
 153             if (!selfex->next) {
 154                 ast_expression_delete_full(self);
 155                 return NULL;
 156             }
 157         }
 158         else
 159             selfex->next = NULL;
 160
 161         for (i = 0; i < fromex->params_count; ++i) {
 162             ast_value *v = ast_value_copy(fromex->params[i]);
 163             if (!v || !ast_expression_common_params_add(selfex, v)) {
 164                 ast_expression_delete_full(self);
 165                 return NULL;
 166             }
 167         }
 168
 169         return self;
 170     }
 171 }
 172
 173 bool ast_compare_type(ast_expression *a, ast_expression *b)
 174 {
 175     if (a->expression.vtype != b->expression.vtype)
 176         return false;
 177     if (!a->expression.next != !b->expression.next)
 178         return false;
 179     if (a->expression.params_count != b->expression.params_count)
 180         return false;
 181     if (a->expression.params_count) {
 182         size_t i;
 183         for (i = 0; i < a->expression.params_count; ++i) {
 184             if (!ast_compare_type((ast_expression*)a->expression.params[i],
 185                                   (ast_expression*)b->expression.params[i]))
 186                 return false;
 187         }
 188     }
 189     if (a->expression.next)
 190         return ast_compare_type(a->expression.next, b->expression.next);
 191     return true;
 192 }
 193
 194 ast_value* ast_value_new(lex_ctx ctx, const char *name, int t)
 195 {
 196     ast_instantiate(ast_value, ctx, ast_value_delete);
 197     ast_expression_init((ast_expression*)self,
 198                         (ast_expression_codegen*)&ast_value_codegen);
 199     self->expression.node.keep = true; /* keep */
 200
 201     self->name = name ? util_strdup(name) : NULL;
 202     self->expression.vtype = t;
 203     self->expression.next  = NULL;
 204     self->isconst = false;
 205     memset(&self->constval, 0, sizeof(self->constval));
 206
 207     self->ir_v    = NULL;
 208
 209     return self;
 210 }
 211
 212 void ast_value_delete(ast_value* self)
 213 {
 214     if (self->name)
 215         mem_d((void*)self->name);
 216     if (self->isconst) {
 217         switch (self->expression.vtype)
 218         {
 219         case TYPE_STRING:
 220             mem_d((void*)self->constval.vstring);
 221             break;
 222         case TYPE_FUNCTION:
 223             /* unlink us from the function node */
 224             self->constval.vfunc->vtype = NULL;
 225             break;
 226         /* NOTE: delete function? currently collected in
 227          * the parser structure
 228          */
 229         default:
 230             break;
 231         }
 232     }
 233     ast_expression_delete((ast_expression*)self);
 234     mem_d(self);
 235 }
 236
 237 bool GMQCC_WARN ast_value_params_add(ast_value *self, ast_value *p)
 238 {
 239     return ast_expression_common_params_add(&self->expression, p);
 240 }
 241
 242 bool ast_value_set_name(ast_value *self, const char *name)
 243 {
 244     if (self->name)
 245         mem_d((void*)self->name);
 246     self->name = util_strdup(name);
 247     return !!self->name;
 248 }
 249
 250 ast_binary* ast_binary_new(lex_ctx ctx, int op,
 251                            ast_expression* left, ast_expression* right)
 252 {
 253     ast_instantiate(ast_binary, ctx, ast_binary_delete);
 254     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_binary_codegen);
 255
 256     self->op = op;
 257     self->left = left;
 258     self->right = right;
 259
 260     if (op >= INSTR_EQ_F && op <= INSTR_GT)
 261         self->expression.vtype = TYPE_FLOAT;
 262     else if (op == INSTR_AND || op == INSTR_OR ||
 263              op == INSTR_BITAND || op == INSTR_BITOR)
 264         self->expression.vtype = TYPE_FLOAT;
 265     else if (op == INSTR_MUL_VF || op == INSTR_MUL_FV)
 266         self->expression.vtype = TYPE_VECTOR;
 267     else if (op == INSTR_MUL_V)
 268         self->expression.vtype = TYPE_FLOAT;
 269     else
 270         self->expression.vtype = left->expression.vtype;
 271
 272     return self;
 273 }
 274
 275 void ast_binary_delete(ast_binary *self)
 276 {
 277     ast_unref(self->left);
 278     ast_unref(self->right);
 279     ast_expression_delete((ast_expression*)self);
 280     mem_d(self);
 281 }
 282
 283 ast_binstore* ast_binstore_new(lex_ctx ctx, int storop, int op,
 284                                ast_expression* left, ast_expression* right)
 285 {
 286     ast_instantiate(ast_binstore, ctx, ast_binstore_delete);
 287     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_binstore_codegen);
 288
 289     self->opstore = storop;
 290     self->opbin   = op;
 291     self->dest    = left;
 292     self->source  = right;
 293
 294     self->expression.vtype = left->expression.vtype;
 295     if (left->expression.next) {
 296         self->expression.next = ast_type_copy(ctx, left);
 297         if (!self->expression.next) {
 298             ast_delete(self);
 299             return NULL;
 300         }
 301     }
 302     else
 303         self->expression.next = NULL;
 304
 305     return self;
 306 }
 307
 308 void ast_binstore_delete(ast_binstore *self)
 309 {
 310     ast_unref(self->dest);
 311     ast_unref(self->source);
 312     ast_expression_delete((ast_expression*)self);
 313     mem_d(self);
 314 }
 315
 316 ast_unary* ast_unary_new(lex_ctx ctx, int op,
 317                          ast_expression *expr)
 318 {
 319     ast_instantiate(ast_unary, ctx, ast_unary_delete);
 320     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_unary_codegen);
 321
 322     self->op = op;
 323     self->operand = expr;
 324
 325     return self;
 326 }
 327
 328 void ast_unary_delete(ast_unary *self)
 329 {
 330     ast_unref(self->operand);
 331     ast_expression_delete((ast_expression*)self);
 332     mem_d(self);
 333 }
 334
 335 ast_return* ast_return_new(lex_ctx ctx, ast_expression *expr)
 336 {
 337     ast_instantiate(ast_return, ctx, ast_return_delete);
 338     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_return_codegen);
 339
 340     self->operand = expr;
 341
 342     return self;
 343 }
 344
 345 void ast_return_delete(ast_return *self)
 346 {
 347     if (self->operand)
 348         ast_unref(self->operand);
 349     ast_expression_delete((ast_expression*)self);
 350     mem_d(self);
 351 }
 352
 353 ast_entfield* ast_entfield_new(lex_ctx ctx, ast_expression *entity, ast_expression *field)
 354 {
 355     const ast_expression *outtype;
 356
 357     ast_instantiate(ast_entfield, ctx, ast_entfield_delete);
 358
 359     if (field->expression.vtype != TYPE_FIELD) {
 360         mem_d(self);
 361         return NULL;
 362     }
 363
 364     outtype = field->expression.next;
 365     if (!outtype) {
 366         mem_d(self);
 367         /* Error: field has no type... */
 368         return NULL;
 369     }
 370
 371     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_entfield_codegen);
 372
 373     self->expression.vtype = outtype->expression.vtype;
 374     self->expression.next  = ast_type_copy(ctx, outtype->expression.next);
 375
 376     self->entity = entity;
 377     self->field  = field;
 378
 379     return self;
 380 }
 381
 382 void ast_entfield_delete(ast_entfield *self)
 383 {
 384     ast_unref(self->entity);
 385     ast_unref(self->field);
 386     ast_expression_delete((ast_expression*)self);
 387     mem_d(self);
 388 }
 389
 390 ast_member* ast_member_new(lex_ctx ctx, ast_expression *owner, unsigned int field)
 391 {
 392     ast_instantiate(ast_member, ctx, ast_member_delete);
 393     if (field >= 3) {
 394         mem_d(self);
 395         return NULL;
 396     }
 397
 398     if (owner->expression.vtype != TYPE_VECTOR &&
 399         owner->expression.vtype != TYPE_FIELD) {
 400         asterror(ctx, "member-access on an invalid owner of type %s\n", type_name[owner->expression.vtype]);
 401         mem_d(self);
 402         return NULL;
 403     }
 404
 405     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_member_codegen);
 406     self->expression.node.keep = true; /* keep */
 407
 408     if (owner->expression.vtype == TYPE_VECTOR) {
 409         self->expression.vtype = TYPE_FLOAT;
 410         self->expression.next  = NULL;
 411     } else {
 412         self->expression.vtype = TYPE_FIELD;
 413         self->expression.next = ast_shallow_type(ctx, TYPE_FLOAT);
 414     }
 415
 416     self->owner = owner;
 417     self->field = field;
 418
 419     return self;
 420 }
 421
 422 void ast_member_delete(ast_member *self)
 423 {
 424     /* The owner is always an ast_value, which has .keep=true,
 425      * also: ast_members are usually deleted after the owner, thus
 426      * this will cause invalid access
 427     ast_unref(self->owner);
 428      * once we allow (expression).x to access a vector-member, we need
 429      * to change this: preferably by creating an alternate ast node for this
 430      * purpose that is not garbage-collected.
 431     */
 432     ast_expression_delete((ast_expression*)self);
 433     mem_d(self);
 434 }
 435
 436 ast_ifthen* ast_ifthen_new(lex_ctx ctx, ast_expression *cond, ast_expression *ontrue, ast_expression *onfalse)
 437 {
 438     ast_instantiate(ast_ifthen, ctx, ast_ifthen_delete);
 439     if (!ontrue && !onfalse) {
 440         /* because it is invalid */
 441         mem_d(self);
 442         return NULL;
 443     }
 444     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_ifthen_codegen);
 445
 446     self->cond     = cond;
 447     self->on_true  = ontrue;
 448     self->on_false = onfalse;
 449
 450     return self;
 451 }
 452
 453 void ast_ifthen_delete(ast_ifthen *self)
 454 {
 455     ast_unref(self->cond);
 456     if (self->on_true)
 457         ast_unref(self->on_true);
 458     if (self->on_false)
 459         ast_unref(self->on_false);
 460     ast_expression_delete((ast_expression*)self);
 461     mem_d(self);
 462 }
 463
 464 ast_ternary* ast_ternary_new(lex_ctx ctx, ast_expression *cond, ast_expression *ontrue, ast_expression *onfalse)
 465 {
 466     ast_instantiate(ast_ternary, ctx, ast_ternary_delete);
 467     /* This time NEITHER must be NULL */
 468     if (!ontrue || !onfalse) {
 469         mem_d(self);
 470         return NULL;
 471     }
 472     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_ternary_codegen);
 473
 474     self->cond     = cond;
 475     self->on_true  = ontrue;
 476     self->on_false = onfalse;
 477     self->phi_out  = NULL;
 478
 479     return self;
 480 }
 481
 482 void ast_ternary_delete(ast_ternary *self)
 483 {
 484     ast_unref(self->cond);
 485     ast_unref(self->on_true);
 486     ast_unref(self->on_false);
 487     ast_expression_delete((ast_expression*)self);
 488     mem_d(self);
 489 }
 490
 491 ast_loop* ast_loop_new(lex_ctx ctx,
 492                        ast_expression *initexpr,
 493                        ast_expression *precond,
 494                        ast_expression *postcond,
 495                        ast_expression *increment,
 496                        ast_expression *body)
 497 {
 498     ast_instantiate(ast_loop, ctx, ast_loop_delete);
 499     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_loop_codegen);
 500
 501     self->initexpr  = initexpr;
 502     self->precond   = precond;
 503     self->postcond  = postcond;
 504     self->increment = increment;
 505     self->body      = body;
 506
 507     return self;
 508 }
 509
 510 void ast_loop_delete(ast_loop *self)
 511 {
 512     if (self->initexpr)
 513         ast_unref(self->initexpr);
 514     if (self->precond)
 515         ast_unref(self->precond);
 516     if (self->postcond)
 517         ast_unref(self->postcond);
 518     if (self->increment)
 519         ast_unref(self->increment);
 520     if (self->body)
 521         ast_unref(self->body);
 522     ast_expression_delete((ast_expression*)self);
 523     mem_d(self);
 524 }
 525
 526 ast_call* ast_call_new(lex_ctx ctx,
 527                        ast_expression *funcexpr)
 528 {
 529     ast_instantiate(ast_call, ctx, ast_call_delete);
 530     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_call_codegen);
 531
 532     MEM_VECTOR_INIT(self, params);
 533
 534     self->func = funcexpr;
 535
 536     self->expression.vtype = funcexpr->expression.next->expression.vtype;
 537     if (funcexpr->expression.next->expression.next)
 538         self->expression.next = ast_type_copy(ctx, funcexpr->expression.next->expression.next);
 539
 540     return self;
 541 }
 542 MEM_VEC_FUNCTIONS(ast_call, ast_expression*, params)
 543
 544 void ast_call_delete(ast_call *self)
 545 {
 546     size_t i;
 547     for (i = 0; i < self->params_count; ++i)
 548         ast_unref(self->params[i]);
 549     MEM_VECTOR_CLEAR(self, params);
 550
 551     if (self->func)
 552         ast_unref(self->func);
 553
 554     ast_expression_delete((ast_expression*)self);
 555     mem_d(self);
 556 }
 557
 558 ast_store* ast_store_new(lex_ctx ctx, int op,
 559                          ast_expression *dest, ast_expression *source)
 560 {
 561     ast_instantiate(ast_store, ctx, ast_store_delete);
 562     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_store_codegen);
 563
 564     self->op = op;
 565     self->dest = dest;
 566     self->source = source;
 567
 568     return self;
 569 }
 570
 571 void ast_store_delete(ast_store *self)
 572 {
 573     ast_unref(self->dest);
 574     ast_unref(self->source);
 575     ast_expression_delete((ast_expression*)self);
 576     mem_d(self);
 577 }
 578
 579 ast_block* ast_block_new(lex_ctx ctx)
 580 {
 581     ast_instantiate(ast_block, ctx, ast_block_delete);
 582     ast_expression_init((ast_expression*)self,
 583                         (ast_expression_codegen*)&ast_block_codegen);
 584
 585     MEM_VECTOR_INIT(self, locals);
 586     MEM_VECTOR_INIT(self, exprs);
 587     MEM_VECTOR_INIT(self, collect);
 588
 589     return self;
 590 }
 591 MEM_VEC_FUNCTIONS(ast_block, ast_value*, locals)
 592 MEM_VEC_FUNCTIONS(ast_block, ast_expression*, exprs)
 593 MEM_VEC_FUNCTIONS(ast_block, ast_expression*, collect)
 594
 595 bool ast_block_collect(ast_block *self, ast_expression *expr)
 596 {
 597     if (!ast_block_collect_add(self, expr))
 598         return false;
 599     expr->expression.node.keep = true;
 600     return true;
 601 }
 602
 603 void ast_block_delete(ast_block *self)
 604 {
 605     size_t i;
 606     for (i = 0; i < self->exprs_count; ++i)
 607         ast_unref(self->exprs[i]);
 608     MEM_VECTOR_CLEAR(self, exprs);
 609     for (i = 0; i < self->locals_count; ++i)
 610         ast_delete(self->locals[i]);
 611     MEM_VECTOR_CLEAR(self, locals);
 612     for (i = 0; i < self->collect_count; ++i)
 613         ast_delete(self->collect[i]);
 614     MEM_VECTOR_CLEAR(self, collect);
 615     ast_expression_delete((ast_expression*)self);
 616     mem_d(self);
 617 }
 618
 619 bool ast_block_set_type(ast_block *self, ast_expression *from)
 620 {
 621     if (self->expression.next)
 622         ast_delete(self->expression.next);
 623     self->expression.vtype = from->expression.vtype;
 624     if (from->expression.next) {
 625         self->expression.next = ast_type_copy(self->expression.node.context, from->expression.next);
 626         if (!self->expression.next)
 627             return false;
 628     }
 629     else
 630         self->expression.next = NULL;
 631     return true;
 632 }
 633
 634 ast_function* ast_function_new(lex_ctx ctx, const char *name, ast_value *vtype)
 635 {
 636     ast_instantiate(ast_function, ctx, ast_function_delete);
 637
 638     if (!vtype ||
 639         vtype->isconst ||
 640         vtype->expression.vtype != TYPE_FUNCTION)
 641     {
 642         mem_d(self);
 643         return NULL;
 644     }
 645
 646     self->vtype = vtype;
 647     self->name = name ? util_strdup(name) : NULL;
 648     MEM_VECTOR_INIT(self, blocks);
 649
 650     self->labelcount = 0;
 651     self->builtin = 0;
 652
 653     self->ir_func = NULL;
 654     self->curblock = NULL;
 655
 656     self->breakblock    = NULL;
 657     self->continueblock = NULL;
 658
 659     vtype->isconst = true;
 660     vtype->constval.vfunc = self;
 661
 662     return self;
 663 }
 664
 665 MEM_VEC_FUNCTIONS(ast_function, ast_block*, blocks)
 666
 667 void ast_function_delete(ast_function *self)
 668 {
 669     size_t i;
 670     if (self->name)
 671         mem_d((void*)self->name);
 672     if (self->vtype) {
 673         /* ast_value_delete(self->vtype); */
 674         self->vtype->isconst = false;
 675         self->vtype->constval.vfunc = NULL;
 676         /* We use unref - if it was stored in a global table it is supposed
 677          * to be deleted from *there*
 678          */
 679         ast_unref(self->vtype);
 680     }
 681     for (i = 0; i < self->blocks_count; ++i)
 682         ast_delete(self->blocks[i]);
 683     MEM_VECTOR_CLEAR(self, blocks);
 684     mem_d(self);
 685 }
 686
 687 static void ast_util_hexitoa(char *buf, size_t size, unsigned int num)
 688 {
 689     unsigned int base = 10;
 690 #define checknul() do { if (size == 1) { *buf = 0; return; } } while (0)
 691 #define addch(x) do { *buf++ = (x); --size; checknul(); } while (0)
 692     if (size < 1)
 693         return;
 694     checknul();
 695     if (!num)
 696         addch('0');
 697     else {
 698         while (num)
 699         {
 700             int digit = num % base;
 701             num /= base;
 702             addch('0' + digit);
 703         }
 704     }
 705
 706     *buf = 0;
 707 #undef addch
 708 #undef checknul
 709 }
 710
 711 const char* ast_function_label(ast_function *self, const char *prefix)
 712 {
 713     size_t id = (self->labelcount++);
 714     size_t len = strlen(prefix);
 715     strncpy(self->labelbuf, prefix, sizeof(self->labelbuf));
 716     ast_util_hexitoa(self->labelbuf + len, sizeof(self->labelbuf)-len, id);
 717     return self->labelbuf;
 718 }
 719
 720 /*********************************************************************/
 721 /* AST codegen part
 722  * by convention you must never pass NULL to the 'ir_value **out'
 723  * parameter. If you really don't care about the output, pass a dummy.
 724  * But I can't imagine a pituation where the output is truly unnecessary.
 725  */
 726
 727 bool ast_value_codegen(ast_value *self, ast_function *func, bool lvalue, ir_value **out)
 728 {
 729     /* NOTE: This is the codegen for a variable used in an expression.
 730      * It is not the codegen to generate the value. For this purpose,
 731      * ast_local_codegen and ast_global_codegen are to be used before this
 732      * is executed. ast_function_codegen should take care of its locals,
 733      * and the ast-user should take care of ast_global_codegen to be used
 734      * on all the globals.
 735      */
 736     if (!self->ir_v) {
 737         asterror(ast_ctx(self), "ast_value used before generated (%s)\n", self->name);
 738         return false;
 739     }
 740     *out = self->ir_v;
 741     return true;
 742 }
 743
 744 bool ast_global_codegen(ast_value *self, ir_builder *ir)
 745 {
 746     ir_value *v = NULL;
 747     if (self->isconst && self->expression.vtype == TYPE_FUNCTION)
 748     {
 749         ir_function *func = ir_builder_create_function(ir, self->name, self->expression.next->expression.vtype);
 750         if (!func)
 751             return false;
 752
 753         self->constval.vfunc->ir_func = func;
 754         self->ir_v = func->value;
 755         /* The function is filled later on ast_function_codegen... */
 756         return true;
 757     }
 758
 759     if (self->expression.vtype == TYPE_FIELD) {
 760         v = ir_builder_create_field(ir, self->name, self->expression.next->expression.vtype);
 761         if (!v)
 762             return false;
 763         if (self->isconst) {
 764             asterror(ast_ctx(self), "TODO: constant field pointers with value\n");
 765             goto error;
 766         }
 767         self->ir_v = v;
 768         return true;
 769     }
 770
 771     v = ir_builder_create_global(ir, self->name, self->expression.vtype);
 772     if (!v) {
 773         asterror(ast_ctx(self), "ir_builder_create_global failed\n");
 774         return false;
 775     }
 776
 777     if (self->isconst) {
 778         switch (self->expression.vtype)
 779         {
 780             case TYPE_FLOAT:
 781                 if (!ir_value_set_float(v, self->constval.vfloat))
 782                     goto error;
 783                 break;
 784             case TYPE_VECTOR:
 785                 if (!ir_value_set_vector(v, self->constval.vvec))
 786                     goto error;
 787                 break;
 788             case TYPE_STRING:
 789                 if (!ir_value_set_string(v, self->constval.vstring))
 790                     goto error;
 791                 break;
 792             case TYPE_FUNCTION:
 793                 asterror(ast_ctx(self), "global of type function not properly generated\n");
 794                 goto error;
 795                 /* Cannot generate an IR value for a function,
 796                  * need a pointer pointing to a function rather.
 797                  */
 798             default:
 799                 asterror(ast_ctx(self), "TODO: global constant type %i\n", self->expression.vtype);
 800                 break;
 801         }
 802     }
 803
 804     /* link us to the ir_value */
 805     self->ir_v = v;
 806     return true;
 807
 808 error: /* clean up */
 809     ir_value_delete(v);
 810     return false;
 811 }
 812
 813 bool ast_local_codegen(ast_value *self, ir_function *func, bool param)
 814 {
 815     ir_value *v = NULL;
 816     if (self->isconst && self->expression.vtype == TYPE_FUNCTION)
 817     {
 818         /* Do we allow local functions? I think not...
 819          * this is NOT a function pointer atm.
 820          */
 821         return false;
 822     }
 823
 824     v = ir_function_create_local(func, self->name, self->expression.vtype, param);
 825     if (!v)
 826         return false;
 827
 828     /* A constant local... hmmm...
 829      * I suppose the IR will have to deal with this
 830      */
 831     if (self->isconst) {
 832         switch (self->expression.vtype)
 833         {
 834             case TYPE_FLOAT:
 835                 if (!ir_value_set_float(v, self->constval.vfloat))
 836                     goto error;
 837                 break;
 838             case TYPE_VECTOR:
 839                 if (!ir_value_set_vector(v, self->constval.vvec))
 840                     goto error;
 841                 break;
 842             case TYPE_STRING:
 843                 if (!ir_value_set_string(v, self->constval.vstring))
 844                     goto error;
 845                 break;
 846             default:
 847                 asterror(ast_ctx(self), "TODO: global constant type %i\n", self->expression.vtype);
 848                 break;
 849         }
 850     }
 851
 852     /* link us to the ir_value */
 853     self->ir_v = v;
 854     return true;
 855
 856 error: /* clean up */
 857     ir_value_delete(v);
 858     return false;
 859 }
 860
 861 bool ast_function_codegen(ast_function *self, ir_builder *ir)
 862 {
 863     ir_function *irf;
 864     ir_value    *dummy;
 865     ast_expression_common *ec;
 866     size_t    i;
 867
 868     irf = self->ir_func;
 869     if (!irf) {
 870         asterror(ast_ctx(self), "ast_function's related ast_value was not generated yet\n");
 871         return false;
 872     }
 873
 874     /* fill the parameter list */
 875     ec = &self->vtype->expression;
 876     for (i = 0; i < ec->params_count; ++i)
 877     {
 878         if (!ir_function_params_add(irf, ec->params[i]->expression.vtype))
 879             return false;
 880         if (!self->builtin) {
 881             if (!ast_local_codegen(ec->params[i], self->ir_func, true))
 882                 return false;
 883         }
 884     }
 885
 886     if (self->builtin) {
 887         irf->builtin = self->builtin;
 888         return true;
 889     }
 890
 891     if (!self->blocks_count) {
 892         asterror(ast_ctx(self), "function `%s` has no body", self->name);
 893         return false;
 894     }
 895
 896     self->curblock = ir_function_create_block(irf, "entry");
 897     if (!self->curblock)
 898         return false;
 899
 900     for (i = 0; i < self->blocks_count; ++i) {
 901         ast_expression_codegen *gen = self->blocks[i]->expression.codegen;
 902         if (!(*gen)((ast_expression*)self->blocks[i], self, false, &dummy))
 903             return false;
 904     }
 905
 906     /* TODO: check return types */
 907     if (!self->curblock->is_return)
 908     {
 909         if (!self->vtype->expression.next ||
 910             self->vtype->expression.next->expression.vtype == TYPE_VOID)
 911         {
 912             return ir_block_create_return(self->curblock, NULL);
 913         }
 914         else
 915         {
 916             /* error("missing return"); */
 917             asterror(ast_ctx(self), "function `%s` missing return value", self->name);
 918             return false;
 919         }
 920     }
 921     return true;
 922 }
 923
 924 /* Note, you will not see ast_block_codegen generate ir_blocks.
 925  * To the AST and the IR, blocks are 2 different things.
 926  * In the AST it represents a block of code, usually enclosed in
 927  * curly braces {...}.
 928  * While in the IR it represents a block in terms of control-flow.
 929  */
 930 bool ast_block_codegen(ast_block *self, ast_function *func, bool lvalue, ir_value **out)
 931 {
 932     size_t i;
 933
 934     /* We don't use this
 935      * Note: an ast-representation using the comma-operator
 936      * of the form: (a, b, c) = x should not assign to c...
 937      */
 938     (void)lvalue;
 939     if (self->expression.outr) {
 940         *out = self->expression.outr;
 941         return true;
 942     }
 943
 944     /* output is NULL at first, we'll have each expression
 945      * assign to out output, thus, a comma-operator represention
 946      * using an ast_block will return the last generated value,
 947      * so: (b, c) + a  executed both b and c, and returns c,
 948      * which is then added to a.
 949      */
 950     *out = NULL;
 951
 952     /* generate locals */
 953     for (i = 0; i < self->locals_count; ++i)
 954     {
 955         if (!ast_local_codegen(self->locals[i], func->ir_func, false))
 956             return false;
 957     }
 958
 959     for (i = 0; i < self->exprs_count; ++i)
 960     {
 961         ast_expression_codegen *gen = self->exprs[i]->expression.codegen;
 962         if (!(*gen)(self->exprs[i], func, false, out))
 963             return false;
 964     }
 965
 966     self->expression.outr = *out;
 967
 968     return true;
 969 }
 970
 971 bool ast_store_codegen(ast_store *self, ast_function *func, bool lvalue, ir_value **out)
 972 {
 973     ast_expression_codegen *cgen;
 974     ir_value *left, *right;
 975
 976     if (lvalue && self->expression.outl) {
 977         *out = self->expression.outl;
 978         return true;
 979     }
 980
 981     if (!lvalue && self->expression.outr) {
 982         *out = self->expression.outr;
 983         return true;
 984     }
 985
 986     cgen = self->dest->expression.codegen;
 987     /* lvalue! */
 988     if (!(*cgen)((ast_expression*)(self->dest), func, true, &left))
 989         return false;
 990     self->expression.outl = left;
 991
 992     cgen = self->source->expression.codegen;
 993     /* rvalue! */
 994     if (!(*cgen)((ast_expression*)(self->source), func, false, &right))
 995         return false;
 996
 997     if (!ir_block_create_store_op(func->curblock, self->op, left, right))
 998         return false;
 999     self->expression.outr = right;
1000
1001     /* Theoretically, an assinment returns its left side as an
1002      * lvalue, if we don't need an lvalue though, we return
1003      * the right side as an rvalue, otherwise we have to
1004      * somehow know whether or not we need to dereference the pointer
1005      * on the left side - that is: OP_LOAD if it was an address.
1006      * Also: in original QC we cannot OP_LOADP *anyway*.
1007      */
1008     *out = (lvalue ? left : right);
1009
1010     return true;
1011 }
1012
1013 bool ast_binary_codegen(ast_binary *self, ast_function *func, bool lvalue, ir_value **out)
1014 {
1015     ast_expression_codegen *cgen;
1016     ir_value *left, *right;
1017
1018     /* In the context of a binary operation, we can disregard
1019      * the lvalue flag.
1020      */
1021     (void)lvalue;
1022     if (self->expression.outr) {
1023         *out = self->expression.outr;
1024         return true;
1025     }
1026
1027     cgen = self->left->expression.codegen;
1028     /* lvalue! */
1029     if (!(*cgen)((ast_expression*)(self->left), func, false, &left))
1030         return false;
1031
1032     cgen = self->right->expression.codegen;
1033     /* rvalue! */
1034     if (!(*cgen)((ast_expression*)(self->right), func, false, &right))
1035         return false;
1036
1037     *out = ir_block_create_binop(func->curblock, ast_function_label(func, "bin"),
1038                                  self->op, left, right);
1039     if (!*out)
1040         return false;
1041     self->expression.outr = *out;
1042
1043     return true;
1044 }
1045
1046 bool ast_binstore_codegen(ast_binstore *self, ast_function *func, bool lvalue, ir_value **out)
1047 {
1048     ast_expression_codegen *cgen;
1049     ir_value *leftl, *leftr, *right, *bin;
1050
1051     if (lvalue && self->expression.outl) {
1052         *out = self->expression.outl;
1053         return true;
1054     }
1055
1056     if (!lvalue && self->expression.outr) {
1057         *out = self->expression.outr;
1058         return true;
1059     }
1060
1061     /* for a binstore we need both an lvalue and an rvalue for the left side */
1062     /* rvalue of destination! */
1063     cgen = self->dest->expression.codegen;
1064     if (!(*cgen)((ast_expression*)(self->dest), func, false, &leftr))
1065         return false;
1066
1067     /* source as rvalue only */
1068     cgen = self->source->expression.codegen;
1069     if (!(*cgen)((ast_expression*)(self->source), func, false, &right))
1070         return false;
1071
1072     /* now the binary */
1073     bin = ir_block_create_binop(func->curblock, ast_function_label(func, "binst"),
1074                                 self->opbin, leftr, right);
1075     self->expression.outr = bin;
1076
1077     /* now store them */
1078     cgen = self->dest->expression.codegen;
1079     /* lvalue of destination */
1080     if (!(*cgen)((ast_expression*)(self->dest), func, true, &leftl))
1081         return false;
1082     self->expression.outl = leftl;
1083
1084     if (!ir_block_create_store_op(func->curblock, self->opstore, leftl, bin))
1085         return false;
1086     self->expression.outr = bin;
1087
1088     /* Theoretically, an assinment returns its left side as an
1089      * lvalue, if we don't need an lvalue though, we return
1090      * the right side as an rvalue, otherwise we have to
1091      * somehow know whether or not we need to dereference the pointer
1092      * on the left side - that is: OP_LOAD if it was an address.
1093      * Also: in original QC we cannot OP_LOADP *anyway*.
1094      */
1095     *out = (lvalue ? leftl : bin);
1096
1097     return true;
1098 }
1099
1100 bool ast_unary_codegen(ast_unary *self, ast_function *func, bool lvalue, ir_value **out)
1101 {
1102     ast_expression_codegen *cgen;
1103     ir_value *operand;
1104
1105     /* In the context of a unary operation, we can disregard
1106      * the lvalue flag.
1107      */
1108     (void)lvalue;
1109     if (self->expression.outr) {
1110         *out = self->expression.outr;
1111         return true;
1112     }
1113
1114     cgen = self->operand->expression.codegen;
1115     /* lvalue! */
1116     if (!(*cgen)((ast_expression*)(self->operand), func, false, &operand))
1117         return false;
1118
1119     *out = ir_block_create_unary(func->curblock, ast_function_label(func, "unary"),
1120                                  self->op, operand);
1121     if (!*out)
1122         return false;
1123     self->expression.outr = *out;
1124
1125     return true;
1126 }
1127
1128 bool ast_return_codegen(ast_return *self, ast_function *func, bool lvalue, ir_value **out)
1129 {
1130     ast_expression_codegen *cgen;
1131     ir_value *operand;
1132
1133     /* In the context of a return operation, we can disregard
1134      * the lvalue flag.
1135      */
1136     (void)lvalue;
1137     if (self->expression.outr) {
1138         asterror(ast_ctx(self), "internal error: ast_return cannot be reused, it bears no result!\n");
1139         return false;
1140     }
1141     self->expression.outr = (ir_value*)1;
1142
1143     if (self->operand) {
1144         cgen = self->operand->expression.codegen;
1145         /* lvalue! */
1146         if (!(*cgen)((ast_expression*)(self->operand), func, false, &operand))
1147             return false;
1148
1149         if (!ir_block_create_return(func->curblock, operand))
1150             return false;
1151     } else {
1152         if (!ir_block_create_return(func->curblock, NULL))
1153             return false;
1154     }
1155
1156     return true;
1157 }
1158
1159 bool ast_entfield_codegen(ast_entfield *self, ast_function *func, bool lvalue, ir_value **out)
1160 {
1161     ast_expression_codegen *cgen;
1162     ir_value *ent, *field;
1163
1164     /* This function needs to take the 'lvalue' flag into account!
1165      * As lvalue we provide a field-pointer, as rvalue we provide the
1166      * value in a temp.
1167      */
1168
1169     if (lvalue && self->expression.outl) {
1170         *out = self->expression.outl;
1171         return true;
1172     }
1173
1174     if (!lvalue && self->expression.outr) {
1175         *out = self->expression.outr;
1176         return true;
1177     }
1178
1179     cgen = self->entity->expression.codegen;
1180     if (!(*cgen)((ast_expression*)(self->entity), func, false, &ent))
1181         return false;
1182
1183     cgen = self->field->expression.codegen;
1184     if (!(*cgen)((ast_expression*)(self->field), func, false, &field))
1185         return false;
1186
1187     if (lvalue) {
1188         /* address! */
1189         *out = ir_block_create_fieldaddress(func->curblock, ast_function_label(func, "efa"),
1190                                             ent, field);
1191     } else {
1192         *out = ir_block_create_load_from_ent(func->curblock, ast_function_label(func, "efv"),
1193                                              ent, field, self->expression.vtype);
1194     }
1195     if (!*out) {
1196         asterror(ast_ctx(self), "failed to create %s instruction (output type %s)",
1197                  (lvalue ? "ADDRESS" : "FIELD"),
1198                  type_name[self->expression.vtype]);
1199         return false;
1200     }
1201
1202     if (lvalue)
1203         self->expression.outl = *out;
1204     else
1205         self->expression.outr = *out;
1206
1207     /* Hm that should be it... */
1208     return true;
1209 }
1210
1211 bool ast_member_codegen(ast_member *self, ast_function *func, bool lvalue, ir_value **out)
1212 {
1213     ast_expression_codegen *cgen;
1214     ir_value *vec;
1215
1216     /* in QC this is always an lvalue */
1217     (void)lvalue;
1218     if (self->expression.outl) {
1219         *out = self->expression.outl;
1220         return true;
1221     }
1222
1223     cgen = self->owner->expression.codegen;
1224     if (!(*cgen)((ast_expression*)(self->owner), func, true, &vec))
1225         return false;
1226
1227     if (vec->vtype != TYPE_VECTOR &&
1228         !(vec->vtype == TYPE_FIELD && self->owner->expression.next->expression.vtype == TYPE_VECTOR))
1229     {
1230         return false;
1231     }
1232
1233     *out = ir_value_vector_member(vec, self->field);
1234     self->expression.outl = *out;
1235
1236     return (*out != NULL);
1237 }
1238
1239 bool ast_ifthen_codegen(ast_ifthen *self, ast_function *func, bool lvalue, ir_value **out)
1240 {
1241     ast_expression_codegen *cgen;
1242
1243     ir_value *condval;
1244     ir_value *dummy;
1245
1246     ir_block *cond = func->curblock;
1247     ir_block *ontrue;
1248     ir_block *onfalse;
1249     ir_block *merge;
1250
1251     /* We don't output any value, thus also don't care about r/lvalue */
1252     (void)out;
1253     (void)lvalue;
1254
1255     if (self->expression.outr) {
1256         asterror(ast_ctx(self), "internal error: ast_ifthen cannot be reused, it bears no result!\n");
1257         return false;
1258     }
1259     self->expression.outr = (ir_value*)1;
1260
1261     /* generate the condition */
1262     func->curblock = cond;
1263     cgen = self->cond->expression.codegen;
1264     if (!(*cgen)((ast_expression*)(self->cond), func, false, &condval))
1265         return false;
1266
1267     /* on-true path */
1268
1269     if (self->on_true) {
1270         /* create on-true block */
1271         ontrue = ir_function_create_block(func->ir_func, ast_function_label(func, "ontrue"));
1272         if (!ontrue)
1273             return false;
1274
1275         /* enter the block */
1276         func->curblock = ontrue;
1277
1278         /* generate */
1279         cgen = self->on_true->expression.codegen;
1280         if (!(*cgen)((ast_expression*)(self->on_true), func, false, &dummy))
1281             return false;
1282     } else
1283         ontrue = NULL;
1284
1285     /* on-false path */
1286     if (self->on_false) {
1287         /* create on-false block */
1288         onfalse = ir_function_create_block(func->ir_func, ast_function_label(func, "onfalse"));
1289         if (!onfalse)
1290             return false;
1291
1292         /* enter the block */
1293         func->curblock = onfalse;
1294
1295         /* generate */
1296         cgen = self->on_false->expression.codegen;
1297         if (!(*cgen)((ast_expression*)(self->on_false), func, false, &dummy))
1298             return false;
1299     } else
1300         onfalse = NULL;
1301
1302     /* Merge block were they all merge in to */
1303     merge = ir_function_create_block(func->ir_func, ast_function_label(func, "endif"));
1304     if (!merge)
1305         return false;
1306
1307     /* add jumps ot the merge block */
1308     if (ontrue && !ir_block_create_jump(ontrue, merge))
1309         return false;
1310     if (onfalse && !ir_block_create_jump(onfalse, merge))
1311         return false;
1312
1313     /* we create the if here, that way all blocks are ordered :)
1314      */
1315     if (!ir_block_create_if(cond, condval,
1316                             (ontrue  ? ontrue  : merge),
1317                             (onfalse ? onfalse : merge)))
1318     {
1319         return false;
1320     }
1321
1322     /* Now enter the merge block */
1323     func->curblock = merge;
1324
1325     return true;
1326 }
1327
1328 bool ast_ternary_codegen(ast_ternary *self, ast_function *func, bool lvalue, ir_value **out)
1329 {
1330     ast_expression_codegen *cgen;
1331
1332     ir_value *condval;
1333     ir_value *trueval, *falseval;
1334     ir_instr *phi;
1335
1336     ir_block *cond = func->curblock;
1337     ir_block *ontrue;
1338     ir_block *onfalse;
1339     ir_block *merge;
1340
1341     /* Ternary can never create an lvalue... */
1342     if (lvalue)
1343         return false;
1344
1345     /* In theory it shouldn't be possible to pass through a node twice, but
1346      * in case we add any kind of optimization pass for the AST itself, it
1347      * may still happen, thus we remember a created ir_value and simply return one
1348      * if it already exists.
1349      */
1350     if (self->phi_out) {
1351         *out = self->phi_out;
1352         return true;
1353     }
1354
1355     /* In the following, contraty to ast_ifthen, we assume both paths exist. */
1356
1357     /* generate the condition */
1358     func->curblock = cond;
1359     cgen = self->cond->expression.codegen;
1360     if (!(*cgen)((ast_expression*)(self->cond), func, false, &condval))
1361         return false;
1362
1363     /* create on-true block */
1364     ontrue = ir_function_create_block(func->ir_func, ast_function_label(func, "tern_T"));
1365     if (!ontrue)
1366         return false;
1367     else
1368     {
1369         /* enter the block */
1370         func->curblock = ontrue;
1371
1372         /* generate */
1373         cgen = self->on_true->expression.codegen;
1374         if (!(*cgen)((ast_expression*)(self->on_true), func, false, &trueval))
1375             return false;
1376     }
1377
1378     /* create on-false block */
1379     onfalse = ir_function_create_block(func->ir_func, ast_function_label(func, "tern_F"));
1380     if (!onfalse)
1381         return false;
1382     else
1383     {
1384         /* enter the block */
1385         func->curblock = onfalse;
1386
1387         /* generate */
1388         cgen = self->on_false->expression.codegen;
1389         if (!(*cgen)((ast_expression*)(self->on_false), func, false, &falseval))
1390             return false;
1391     }
1392
1393     /* create merge block */
1394     merge = ir_function_create_block(func->ir_func, ast_function_label(func, "tern_out"));
1395     if (!merge)
1396         return false;
1397     /* jump to merge block */
1398     if (!ir_block_create_jump(ontrue, merge))
1399         return false;
1400     if (!ir_block_create_jump(onfalse, merge))
1401         return false;
1402
1403     /* create if instruction */
1404     if (!ir_block_create_if(cond, condval, ontrue, onfalse))
1405         return false;
1406
1407     /* Now enter the merge block */
1408     func->curblock = merge;
1409
1410     /* Here, now, we need a PHI node
1411      * but first some sanity checking...
1412      */
1413     if (trueval->vtype != falseval->vtype) {
1414         /* error("ternary with different types on the two sides"); */
1415         return false;
1416     }
1417
1418     /* create PHI */
1419     phi = ir_block_create_phi(merge, ast_function_label(func, "phi"), trueval->vtype);
1420     if (!phi ||
1421         !ir_phi_add(phi, ontrue,  trueval) ||
1422         !ir_phi_add(phi, onfalse, falseval))
1423     {
1424         return false;
1425     }
1426
1427     self->phi_out = ir_phi_value(phi);
1428     *out = self->phi_out;
1429
1430     return true;
1431 }
1432
1433 bool ast_loop_codegen(ast_loop *self, ast_function *func, bool lvalue, ir_value **out)
1434 {
1435     ast_expression_codegen *cgen;
1436
1437     ir_value *dummy      = NULL;
1438     ir_value *precond    = NULL;
1439     ir_value *postcond   = NULL;
1440
1441     /* Since we insert some jumps "late" so we have blocks
1442      * ordered "nicely", we need to keep track of the actual end-blocks
1443      * of expressions to add the jumps to.
1444      */
1445     ir_block *bbody      = NULL, *end_bbody      = NULL;
1446     ir_block *bprecond   = NULL, *end_bprecond   = NULL;
1447     ir_block *bpostcond  = NULL, *end_bpostcond  = NULL;
1448     ir_block *bincrement = NULL, *end_bincrement = NULL;
1449     ir_block *bout       = NULL, *bin            = NULL;
1450
1451     /* let's at least move the outgoing block to the end */
1452     size_t    bout_id;
1453
1454     /* 'break' and 'continue' need to be able to find the right blocks */
1455     ir_block *bcontinue     = NULL;
1456     ir_block *bbreak        = NULL;
1457
1458     ir_block *old_bcontinue = NULL;
1459     ir_block *old_bbreak    = NULL;
1460
1461     ir_block *tmpblock      = NULL;
1462
1463     (void)lvalue;
1464     (void)out;
1465
1466     if (self->expression.outr) {
1467         asterror(ast_ctx(self), "internal error: ast_loop cannot be reused, it bears no result!\n");
1468         return false;
1469     }
1470     self->expression.outr = (ir_value*)1;
1471
1472     /* NOTE:
1473      * Should we ever need some kind of block ordering, better make this function
1474      * move blocks around than write a block ordering algorithm later... after all
1475      * the ast and ir should work together, not against each other.
1476      */
1477
1478     /* initexpr doesn't get its own block, it's pointless, it could create more blocks
1479      * anyway if for example it contains a ternary.
1480      */
1481     if (self->initexpr)
1482     {
1483         cgen = self->initexpr->expression.codegen;
1484         if (!(*cgen)((ast_expression*)(self->initexpr), func, false, &dummy))
1485             return false;
1486     }
1487
1488     /* Store the block from which we enter this chaos */
1489     bin = func->curblock;
1490
1491     /* The pre-loop condition needs its own block since we
1492      * need to be able to jump to the start of that expression.
1493      */
1494     if (self->precond)
1495     {
1496         bprecond = ir_function_create_block(func->ir_func, ast_function_label(func, "pre_loop_cond"));
1497         if (!bprecond)
1498             return false;
1499
1500         /* the pre-loop-condition the least important place to 'continue' at */
1501         bcontinue = bprecond;
1502
1503         /* enter */
1504         func->curblock = bprecond;
1505
1506         /* generate */
1507         cgen = self->precond->expression.codegen;
1508         if (!(*cgen)((ast_expression*)(self->precond), func, false, &precond))
1509             return false;
1510
1511         end_bprecond = func->curblock;
1512     } else {
1513         bprecond = end_bprecond = NULL;
1514     }
1515
1516     /* Now the next blocks won't be ordered nicely, but we need to
1517      * generate them this early for 'break' and 'continue'.
1518      */
1519     if (self->increment) {
1520         bincrement = ir_function_create_block(func->ir_func, ast_function_label(func, "loop_increment"));
1521         if (!bincrement)
1522             return false;
1523         bcontinue = bincrement; /* increment comes before the pre-loop-condition */
1524     } else {
1525         bincrement = end_bincrement = NULL;
1526     }
1527
1528     if (self->postcond) {
1529         bpostcond = ir_function_create_block(func->ir_func, ast_function_label(func, "post_loop_cond"));
1530         if (!bpostcond)
1531             return false;
1532         bcontinue = bpostcond; /* postcond comes before the increment */
1533     } else {
1534         bpostcond = end_bpostcond = NULL;
1535     }
1536
1537     bout_id = func->ir_func->blocks_count;
1538     bout = ir_function_create_block(func->ir_func, ast_function_label(func, "after_loop"));
1539     if (!bout)
1540         return false;
1541     bbreak = bout;
1542
1543     /* The loop body... */
1544     if (self->body)
1545     {
1546         bbody = ir_function_create_block(func->ir_func, ast_function_label(func, "loop_body"));
1547         if (!bbody)
1548             return false;
1549
1550         /* enter */
1551         func->curblock = bbody;
1552
1553         old_bbreak          = func->breakblock;
1554         old_bcontinue       = func->continueblock;
1555         func->breakblock    = bbreak;
1556         func->continueblock = bcontinue;
1557
1558         /* generate */
1559         cgen = self->body->expression.codegen;
1560         if (!(*cgen)((ast_expression*)(self->body), func, false, &dummy))
1561             return false;
1562
1563         end_bbody = func->curblock;
1564         func->breakblock    = old_bbreak;
1565         func->continueblock = old_bcontinue;
1566     }
1567
1568     /* post-loop-condition */
1569     if (self->postcond)
1570     {
1571         /* enter */
1572         func->curblock = bpostcond;
1573
1574         /* generate */
1575         cgen = self->postcond->expression.codegen;
1576         if (!(*cgen)((ast_expression*)(self->postcond), func, false, &postcond))
1577             return false;
1578
1579         end_bpostcond = func->curblock;
1580     }
1581
1582     /* The incrementor */
1583     if (self->increment)
1584     {
1585         /* enter */
1586         func->curblock = bincrement;
1587
1588         /* generate */
1589         cgen = self->increment->expression.codegen;
1590         if (!(*cgen)((ast_expression*)(self->increment), func, false, &dummy))
1591             return false;
1592
1593         end_bincrement = func->curblock;
1594     }
1595
1596     /* In any case now, we continue from the outgoing block */
1597     func->curblock = bout;
1598
1599     /* Now all blocks are in place */
1600     /* From 'bin' we jump to whatever comes first */
1601     if      (bprecond)   tmpblock = bprecond;
1602     else if (bbody)      tmpblock = bbody;
1603     else if (bpostcond)  tmpblock = bpostcond;
1604     else                 tmpblock = bout;
1605     if (!ir_block_create_jump(bin, tmpblock))
1606         return false;
1607
1608     /* From precond */
1609     if (bprecond)
1610     {
1611         ir_block *ontrue, *onfalse;
1612         if      (bbody)      ontrue = bbody;
1613         else if (bincrement) ontrue = bincrement;
1614         else if (bpostcond)  ontrue = bpostcond;
1615         else                 ontrue = bprecond;
1616         onfalse = bout;
1617         if (!ir_block_create_if(end_bprecond, precond, ontrue, onfalse))
1618             return false;
1619     }
1620
1621     /* from body */
1622     if (bbody)
1623     {
1624         if      (bincrement) tmpblock = bincrement;
1625         else if (bpostcond)  tmpblock = bpostcond;
1626         else if (bprecond)   tmpblock = bprecond;
1627         else                 tmpblock = bout;
1628         if (!ir_block_create_jump(end_bbody, tmpblock))
1629             return false;
1630     }
1631
1632     /* from increment */
1633     if (bincrement)
1634     {
1635         if      (bpostcond)  tmpblock = bpostcond;
1636         else if (bprecond)   tmpblock = bprecond;
1637         else if (bbody)      tmpblock = bbody;
1638         else                 tmpblock = bout;
1639         if (!ir_block_create_jump(end_bincrement, tmpblock))
1640             return false;
1641     }
1642
1643     /* from postcond */
1644     if (bpostcond)
1645     {
1646         ir_block *ontrue, *onfalse;
1647         if      (bprecond)   ontrue = bprecond;
1648         else if (bbody)      ontrue = bbody;
1649         else if (bincrement) ontrue = bincrement;
1650         else                 ontrue = bpostcond;
1651         onfalse = bout;
1652         if (!ir_block_create_if(end_bpostcond, postcond, ontrue, onfalse))
1653             return false;
1654     }
1655
1656     /* Move 'bout' to the end */
1657     if (!ir_function_blocks_remove(func->ir_func, bout_id) ||
1658         !ir_function_blocks_add(func->ir_func, bout))
1659     {
1660         ir_block_delete(bout);
1661         return false;
1662     }
1663
1664     return true;
1665 }
1666
1667 bool ast_call_codegen(ast_call *self, ast_function *func, bool lvalue, ir_value **out)
1668 {
1669     ast_expression_codegen *cgen;
1670     ir_value_vector         params;
1671     ir_instr               *callinstr;
1672     size_t i;
1673
1674     ir_value *funval = NULL;
1675
1676     /* return values are never lvalues */
1677     (void)lvalue;
1678
1679     if (self->expression.outr) {
1680         *out = self->expression.outr;
1681         return true;
1682     }
1683
1684     cgen = self->func->expression.codegen;
1685     if (!(*cgen)((ast_expression*)(self->func), func, false, &funval))
1686         return false;
1687     if (!funval)
1688         return false;
1689
1690     MEM_VECTOR_INIT(&params, v);
1691
1692     /* parameters */
1693     for (i = 0; i < self->params_count; ++i)
1694     {
1695         ir_value *param;
1696         ast_expression *expr = self->params[i];
1697
1698         cgen = expr->expression.codegen;
1699         if (!(*cgen)(expr, func, false, &param))
1700             goto error;
1701         if (!param)
1702             goto error;
1703         if (!ir_value_vector_v_add(&params, param))
1704             goto error;
1705     }
1706
1707     callinstr = ir_block_create_call(func->curblock, ast_function_label(func, "call"), funval);
1708     if (!callinstr)
1709         goto error;
1710
1711     for (i = 0; i < params.v_count; ++i) {
1712         if (!ir_call_param(callinstr, params.v[i]))
1713             goto error;
1714     }
1715
1716     *out = ir_call_value(callinstr);
1717     self->expression.outr = *out;
1718
1719     MEM_VECTOR_CLEAR(&params, v);
1720     return true;
1721 error:
1722     MEM_VECTOR_CLEAR(&params, v);
1723     return false;
1724 }