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