ast.c

   1 /*
   2  * Copyright (C) 2012
   3  *     Wolfgang Bumiller
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a copy of
   6  * this software and associated documentation files (the "Software"), to deal in
   7  * the Software without restriction, including without limitation the rights to
   8  * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
   9  * of the Software, and to permit persons to whom the Software is furnished to do
  10  * so, subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice shall be included in all
  13  * copies or substantial portions of the Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  18  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  20  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  21  * SOFTWARE.
  22  */
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26
  27 #include "gmqcc.h"
  28 #include "ast.h"
  29
  30 #define ast_instantiate(T, ctx, destroyfn)                          \
  31     T* self = (T*)mem_a(sizeof(T));                                 \
  32     if (!self) {                                                    \
  33         return NULL;                                                \
  34     }                                                               \
  35     ast_node_init((ast_node*)self, ctx);                            \
  36     ( (ast_node*)self )->node.destroy = (ast_node_delete*)destroyfn
  37
  38 /* It must not be possible to get here. */
  39 static GMQCC_NORETURN void _ast_node_destroy(ast_node *self)
  40 {
  41     fprintf(stderr, "ast node missing destroy()\n");
  42     abort();
  43 }
  44
  45 /* Initialize main ast node aprts */
  46 static void ast_node_init(ast_node *self, lex_ctx ctx)
  47 {
  48     self->node.context = ctx;
  49     self->node.destroy = &_ast_node_destroy;
  50     self->node.keep    = false;
  51 }
  52
  53 /* General expression initialization */
  54 static void ast_expression_init(ast_expression *self,
  55                                 ast_expression_codegen *codegen)
  56 {
  57     self->expression.codegen = codegen;
  58     self->expression.vtype   = TYPE_VOID;
  59     self->expression.next    = NULL;
  60 }
  61
  62 static void ast_expression_delete(ast_expression *self)
  63 {
  64     if (self->expression.next)
  65         ast_delete(self->expression.next);
  66 }
  67
  68 static void ast_expression_delete_full(ast_expression *self)
  69 {
  70     ast_expression_delete(self);
  71     mem_d(self);
  72 }
  73
  74 static ast_expression* ast_type_copy(lex_ctx ctx, const ast_expression *ex)
  75 {
  76     const ast_expression_common *cpex;
  77     ast_expression_common *selfex;
  78
  79     if (!ex)
  80         return NULL;
  81     else
  82     {
  83         ast_instantiate(ast_expression, ctx, ast_expression_delete_full);
  84
  85         cpex   = &ex->expression;
  86         selfex = &self->expression;
  87
  88         selfex->vtype = cpex->vtype;
  89         if (cpex->next)
  90         {
  91             selfex->next = ast_type_copy(ctx, cpex->next);
  92             if (!selfex->next) {
  93                 mem_d(self);
  94                 return NULL;
  95             }
  96         }
  97         else
  98             selfex->next = NULL;
  99
 100         /* This may never be codegen()d */
 101         selfex->codegen = NULL;
 102         return self;
 103     }
 104 }
 105
 106 ast_value* ast_value_new(lex_ctx ctx, const char *name, int t)
 107 {
 108     ast_instantiate(ast_value, ctx, ast_value_delete);
 109     ast_expression_init((ast_expression*)self,
 110                         (ast_expression_codegen*)&ast_value_codegen);
 111     self->expression.node.keep = true; /* keep */
 112
 113     self->name = name ? util_strdup(name) : NULL;
 114     self->expression.vtype = t;
 115     self->expression.next  = NULL;
 116     MEM_VECTOR_INIT(self, params);
 117     self->isconst = false;
 118     memset(&self->constval, 0, sizeof(self->constval));
 119
 120     self->ir_v    = NULL;
 121
 122     return self;
 123 }
 124 MEM_VEC_FUNCTIONS(ast_value, ast_value*, params)
 125
 126 void ast_value_delete(ast_value* self)
 127 {
 128     size_t i;
 129     if (self->name)
 130         mem_d((void*)self->name);
 131     for (i = 0; i < self->params_count; ++i)
 132         ast_value_delete(self->params[i]); /* delete, the ast_function is expected to die first */
 133     MEM_VECTOR_CLEAR(self, params);
 134     if (self->isconst) {
 135         switch (self->expression.vtype)
 136         {
 137         case TYPE_STRING:
 138             mem_d((void*)self->constval.vstring);
 139             break;
 140         case TYPE_FUNCTION:
 141             /* unlink us from the function node */
 142             self->constval.vfunc->vtype = NULL;
 143             break;
 144         /* NOTE: delete function? currently collected in
 145          * the parser structure
 146          */
 147         default:
 148             break;
 149         }
 150     }
 151     ast_expression_delete((ast_expression*)self);
 152     mem_d(self);
 153 }
 154
 155 bool ast_value_set_name(ast_value *self, const char *name)
 156 {
 157     if (self->name)
 158         mem_d((void*)self->name);
 159     self->name = util_strdup(name);
 160     return !!self->name;
 161 }
 162
 163 ast_binary* ast_binary_new(lex_ctx ctx, int op,
 164                            ast_expression* left, ast_expression* right)
 165 {
 166     ast_instantiate(ast_binary, ctx, ast_binary_delete);
 167     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_binary_codegen);
 168
 169     self->op = op;
 170     self->left = left;
 171     self->right = right;
 172
 173     return self;
 174 }
 175
 176 void ast_binary_delete(ast_binary *self)
 177 {
 178     ast_unref(self->left);
 179     ast_unref(self->right);
 180     ast_expression_delete((ast_expression*)self);
 181     mem_d(self);
 182 }
 183
 184 ast_unary* ast_unary_new(lex_ctx ctx, int op,
 185                          ast_expression *expr)
 186 {
 187     ast_instantiate(ast_unary, ctx, ast_unary_delete);
 188     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_unary_codegen);
 189
 190     self->op = op;
 191     self->operand = expr;
 192
 193     return self;
 194 }
 195
 196 void ast_unary_delete(ast_unary *self)
 197 {
 198     ast_unref(self->operand);
 199     ast_expression_delete((ast_expression*)self);
 200     mem_d(self);
 201 }
 202
 203 ast_return* ast_return_new(lex_ctx ctx, int op,
 204                          ast_expression *expr)
 205 {
 206     ast_instantiate(ast_return, ctx, ast_return_delete);
 207     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_return_codegen);
 208
 209     self->operand = expr;
 210
 211     return self;
 212 }
 213
 214 void ast_return_delete(ast_return *self)
 215 {
 216     ast_unref(self->operand);
 217     ast_expression_delete((ast_expression*)self);
 218     mem_d(self);
 219 }
 220
 221 ast_entfield* ast_entfield_new(lex_ctx ctx, ast_expression *entity, ast_expression *field)
 222 {
 223     const ast_expression *outtype;
 224
 225     ast_instantiate(ast_entfield, ctx, ast_entfield_delete);
 226
 227     if (field->expression.vtype != TYPE_FIELD) {
 228         mem_d(self);
 229         return NULL;
 230     }
 231
 232     outtype = field->expression.next;
 233     if (!outtype) {
 234         mem_d(self);
 235         /* Error: field has no type... */
 236         return NULL;
 237     }
 238
 239     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_entfield_codegen);
 240
 241     self->expression.vtype = outtype->expression.vtype;
 242     self->expression.next  = ast_type_copy(ctx, outtype->expression.next);
 243
 244     self->entity = entity;
 245     self->field  = field;
 246
 247     return self;
 248 }
 249
 250 void ast_entfield_delete(ast_entfield *self)
 251 {
 252     ast_unref(self->entity);
 253     ast_unref(self->field);
 254     ast_expression_delete((ast_expression*)self);
 255     mem_d(self);
 256 }
 257
 258 ast_ifthen* ast_ifthen_new(lex_ctx ctx, ast_expression *cond, ast_expression *ontrue, ast_expression *onfalse)
 259 {
 260     ast_instantiate(ast_ifthen, ctx, ast_ifthen_delete);
 261     if (!ontrue && !onfalse) {
 262         /* because it is invalid */
 263         mem_d(self);
 264         return NULL;
 265     }
 266     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_ifthen_codegen);
 267
 268     self->cond     = cond;
 269     self->on_true  = ontrue;
 270     self->on_false = onfalse;
 271
 272     return self;
 273 }
 274
 275 void ast_ifthen_delete(ast_ifthen *self)
 276 {
 277     ast_unref(self->cond);
 278     if (self->on_true)
 279         ast_unref(self->on_true);
 280     if (self->on_false)
 281         ast_unref(self->on_false);
 282     ast_expression_delete((ast_expression*)self);
 283     mem_d(self);
 284 }
 285
 286 ast_ternary* ast_ternary_new(lex_ctx ctx, ast_expression *cond, ast_expression *ontrue, ast_expression *onfalse)
 287 {
 288     ast_instantiate(ast_ternary, ctx, ast_ternary_delete);
 289     /* This time NEITHER must be NULL */
 290     if (!ontrue || !onfalse) {
 291         mem_d(self);
 292         return NULL;
 293     }
 294     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_ternary_codegen);
 295
 296     self->cond     = cond;
 297     self->on_true  = ontrue;
 298     self->on_false = onfalse;
 299     self->phi_out  = NULL;
 300
 301     return self;
 302 }
 303
 304 void ast_ternary_delete(ast_ternary *self)
 305 {
 306     ast_unref(self->cond);
 307     ast_unref(self->on_true);
 308     ast_unref(self->on_false);
 309     ast_expression_delete((ast_expression*)self);
 310     mem_d(self);
 311 }
 312
 313 ast_loop* ast_loop_new(lex_ctx ctx,
 314                        ast_expression *initexpr,
 315                        ast_expression *precond,
 316                        ast_expression *postcond,
 317                        ast_expression *increment,
 318                        ast_expression *body)
 319 {
 320     ast_instantiate(ast_loop, ctx, ast_loop_delete);
 321     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_loop_codegen);
 322
 323     self->initexpr  = initexpr;
 324     self->precond   = precond;
 325     self->postcond  = postcond;
 326     self->increment = increment;
 327     self->body      = body;
 328
 329     return self;
 330 }
 331
 332 void ast_loop_delete(ast_loop *self)
 333 {
 334     if (self->initexpr)
 335         ast_unref(self->initexpr);
 336     if (self->precond)
 337         ast_unref(self->precond);
 338     if (self->postcond)
 339         ast_unref(self->postcond);
 340     if (self->increment)
 341         ast_unref(self->increment);
 342     if (self->body)
 343         ast_unref(self->body);
 344     ast_expression_delete((ast_expression*)self);
 345     mem_d(self);
 346 }
 347
 348 ast_call* ast_call_new(lex_ctx ctx,
 349                        ast_expression *funcexpr)
 350 {
 351     ast_instantiate(ast_call, ctx, ast_call_delete);
 352     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_call_codegen);
 353
 354     MEM_VECTOR_INIT(self, params);
 355
 356     self->func = funcexpr;
 357
 358     return self;
 359 }
 360 MEM_VEC_FUNCTIONS(ast_call, ast_expression*, params)
 361
 362 void ast_call_delete(ast_call *self)
 363 {
 364     size_t i;
 365     for (i = 0; i < self->params_count; ++i)
 366         ast_unref(self->params[i]);
 367     MEM_VECTOR_CLEAR(self, params);
 368
 369     if (self->func)
 370         ast_unref(self->func);
 371
 372     ast_expression_delete((ast_expression*)self);
 373     mem_d(self);
 374 }
 375
 376 ast_store* ast_store_new(lex_ctx ctx, int op,
 377                          ast_value *dest, ast_expression *source)
 378 {
 379     ast_instantiate(ast_store, ctx, ast_store_delete);
 380     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_store_codegen);
 381
 382     self->op = op;
 383     self->dest = dest;
 384     self->source = source;
 385
 386     return self;
 387 }
 388
 389 void ast_store_delete(ast_store *self)
 390 {
 391     ast_unref(self->dest);
 392     ast_unref(self->source);
 393     ast_expression_delete((ast_expression*)self);
 394     mem_d(self);
 395 }
 396
 397 ast_block* ast_block_new(lex_ctx ctx)
 398 {
 399     ast_instantiate(ast_block, ctx, ast_block_delete);
 400     ast_expression_init((ast_expression*)self,
 401                         (ast_expression_codegen*)&ast_block_codegen);
 402
 403     MEM_VECTOR_INIT(self, locals);
 404     MEM_VECTOR_INIT(self, exprs);
 405
 406     return self;
 407 }
 408 MEM_VEC_FUNCTIONS(ast_block, ast_value*, locals)
 409 MEM_VEC_FUNCTIONS(ast_block, ast_expression*, exprs)
 410
 411 void ast_block_delete(ast_block *self)
 412 {
 413     size_t i;
 414     for (i = 0; i < self->exprs_count; ++i)
 415         ast_unref(self->exprs[i]);
 416     MEM_VECTOR_CLEAR(self, exprs);
 417     for (i = 0; i < self->locals_count; ++i)
 418         ast_delete(self->locals[i]);
 419     MEM_VECTOR_CLEAR(self, locals);
 420     ast_expression_delete((ast_expression*)self);
 421     mem_d(self);
 422 }
 423
 424 ast_function* ast_function_new(lex_ctx ctx, const char *name, ast_value *vtype)
 425 {
 426     ast_instantiate(ast_function, ctx, ast_function_delete);
 427
 428     if (!vtype ||
 429         vtype->isconst ||
 430         vtype->expression.vtype != TYPE_FUNCTION)
 431     {
 432         mem_d(self);
 433         return NULL;
 434     }
 435
 436     self->vtype = vtype;
 437     self->name = name ? util_strdup(name) : NULL;
 438     MEM_VECTOR_INIT(self, blocks);
 439
 440     self->labelcount = 0;
 441     self->builtin = 0;
 442
 443     self->ir_func = NULL;
 444     self->curblock = NULL;
 445
 446     self->breakblock    = NULL;
 447     self->continueblock = NULL;
 448
 449     vtype->isconst = true;
 450     vtype->constval.vfunc = self;
 451
 452     return self;
 453 }
 454
 455 MEM_VEC_FUNCTIONS(ast_function, ast_block*, blocks)
 456
 457 void ast_function_delete(ast_function *self)
 458 {
 459     size_t i;
 460     if (self->name)
 461         mem_d((void*)self->name);
 462     if (self->vtype) {
 463         /* ast_value_delete(self->vtype); */
 464         self->vtype->isconst = false;
 465         self->vtype->constval.vfunc = NULL;
 466         /* We use unref - if it was stored in a global table it is supposed
 467          * to be deleted from *there*
 468          */
 469         ast_unref(self->vtype);
 470     }
 471     for (i = 0; i < self->blocks_count; ++i)
 472         ast_delete(self->blocks[i]);
 473     MEM_VECTOR_CLEAR(self, blocks);
 474     mem_d(self);
 475 }
 476
 477 static void ast_util_hexitoa(char *buf, size_t size, unsigned int num)
 478 {
 479     unsigned int base = 10;
 480 #define checknul() do { if (size == 1) { *buf = 0; return; } } while (0)
 481 #define addch(x) do { *buf++ = (x); --size; checknul(); } while (0)
 482     if (size < 1)
 483         return;
 484     checknul();
 485     if (!num)
 486         addch('0');
 487     else {
 488         while (num)
 489         {
 490             int digit = num % base;
 491             num /= base;
 492             addch('0' + digit);
 493         }
 494     }
 495
 496     *buf = 0;
 497 #undef addch
 498 #undef checknul
 499 }
 500
 501 const char* ast_function_label(ast_function *self, const char *prefix)
 502 {
 503     size_t id = (self->labelcount++);
 504     size_t len = strlen(prefix);
 505     strncpy(self->labelbuf, prefix, sizeof(self->labelbuf));
 506     ast_util_hexitoa(self->labelbuf + len, sizeof(self->labelbuf)-len, id);
 507     return self->labelbuf;
 508 }
 509
 510 /*********************************************************************/
 511 /* AST codegen part
 512  * by convention you must never pass NULL to the 'ir_value **out'
 513  * parameter. If you really don't care about the output, pass a dummy.
 514  * But I can't imagine a pituation where the output is truly unnecessary.
 515  */
 516
 517 bool ast_value_codegen(ast_value *self, ast_function *func, bool lvalue, ir_value **out)
 518 {
 519     /* NOTE: This is the codegen for a variable used in an expression.
 520      * It is not the codegen to generate the value. For this purpose,
 521      * ast_local_codegen and ast_global_codegen are to be used before this
 522      * is executed. ast_function_codegen should take care of its locals,
 523      * and the ast-user should take care of ast_global_codegen to be used
 524      * on all the globals.
 525      */
 526     if (!self->ir_v) {
 527         printf("ast_value used before generated (%s)\n", self->name);
 528         return false;
 529     }
 530     *out = self->ir_v;
 531     return true;
 532 }
 533
 534 bool ast_global_codegen(ast_value *self, ir_builder *ir)
 535 {
 536     ir_value *v = NULL;
 537     if (self->isconst && self->expression.vtype == TYPE_FUNCTION)
 538     {
 539         ir_function *func = ir_builder_create_function(ir, self->name, self->expression.next->expression.vtype);
 540         if (!func)
 541             return false;
 542
 543         self->constval.vfunc->ir_func = func;
 544         self->ir_v = func->value;
 545         /* The function is filled later on ast_function_codegen... */
 546         return true;
 547     }
 548
 549     v = ir_builder_create_global(ir, self->name, self->expression.vtype);
 550     if (!v)
 551         return false;
 552
 553     if (self->isconst) {
 554         switch (self->expression.vtype)
 555         {
 556             case TYPE_FLOAT:
 557                 if (!ir_value_set_float(v, self->constval.vfloat))
 558                     goto error;
 559                 break;
 560             case TYPE_VECTOR:
 561                 if (!ir_value_set_vector(v, self->constval.vvec))
 562                     goto error;
 563                 break;
 564             case TYPE_STRING:
 565                 if (!ir_value_set_string(v, self->constval.vstring))
 566                     goto error;
 567                 break;
 568             case TYPE_FUNCTION:
 569                 printf("global of type function not properly generated\n");
 570                 goto error;
 571                 /* Cannot generate an IR value for a function,
 572                  * need a pointer pointing to a function rather.
 573                  */
 574             default:
 575                 printf("TODO: global constant type %i\n", self->expression.vtype);
 576                 break;
 577         }
 578     }
 579
 580     /* link us to the ir_value */
 581     self->ir_v = v;
 582     return true;
 583
 584 error: /* clean up */
 585     ir_value_delete(v);
 586     return false;
 587 }
 588
 589 bool ast_local_codegen(ast_value *self, ir_function *func, bool param)
 590 {
 591     ir_value *v = NULL;
 592     if (self->isconst && self->expression.vtype == TYPE_FUNCTION)
 593     {
 594         /* Do we allow local functions? I think not...
 595          * this is NOT a function pointer atm.
 596          */
 597         return false;
 598     }
 599
 600     v = ir_function_create_local(func, self->name, self->expression.vtype, param);
 601     if (!v)
 602         return false;
 603
 604     /* A constant local... hmmm...
 605      * I suppose the IR will have to deal with this
 606      */
 607     if (self->isconst) {
 608         switch (self->expression.vtype)
 609         {
 610             case TYPE_FLOAT:
 611                 if (!ir_value_set_float(v, self->constval.vfloat))
 612                     goto error;
 613                 break;
 614             case TYPE_VECTOR:
 615                 if (!ir_value_set_vector(v, self->constval.vvec))
 616                     goto error;
 617                 break;
 618             case TYPE_STRING:
 619                 if (!ir_value_set_string(v, self->constval.vstring))
 620                     goto error;
 621                 break;
 622             default:
 623                 printf("TODO: global constant type %i\n", self->expression.vtype);
 624                 break;
 625         }
 626     }
 627
 628     /* link us to the ir_value */
 629     self->ir_v = v;
 630     return true;
 631
 632 error: /* clean up */
 633     ir_value_delete(v);
 634     return false;
 635 }
 636
 637 bool ast_function_codegen(ast_function *self, ir_builder *ir)
 638 {
 639     ir_function *irf;
 640     ir_value    *dummy;
 641     size_t    i;
 642
 643     irf = self->ir_func;
 644     if (!irf) {
 645         printf("ast_function's related ast_value was not generated yet\n");
 646         return false;
 647     }
 648
 649     /* fill the parameter list */
 650     for (i = 0; i < self->vtype->params_count; ++i)
 651     {
 652         if (!ir_function_params_add(irf, self->vtype->params[i]->expression.vtype))
 653             return false;
 654         if (!self->builtin) {
 655             if (!ast_local_codegen(self->vtype->params[i], self->ir_func, true))
 656                 return false;
 657         }
 658     }
 659
 660     if (self->builtin) {
 661         irf->builtin = self->builtin;
 662         return true;
 663     }
 664
 665     self->curblock = ir_function_create_block(irf, "entry");
 666     if (!self->curblock)
 667         return false;
 668
 669     for (i = 0; i < self->blocks_count; ++i) {
 670         ast_expression_codegen *gen = self->blocks[i]->expression.codegen;
 671         if (!(*gen)((ast_expression*)self->blocks[i], self, false, &dummy))
 672             return false;
 673     }
 674
 675     /* TODO: check return types */
 676     if (!self->curblock->is_return)
 677     {
 678         if (!self->vtype->expression.next ||
 679             self->vtype->expression.next->expression.vtype == TYPE_VOID)
 680         {
 681             return ir_block_create_return(self->curblock, NULL);
 682         }
 683         else
 684         {
 685             /* error("missing return"); */
 686             return false;
 687         }
 688     }
 689     return true;
 690 }
 691
 692 /* Note, you will not see ast_block_codegen generate ir_blocks.
 693  * To the AST and the IR, blocks are 2 different things.
 694  * In the AST it represents a block of code, usually enclosed in
 695  * curly braces {...}.
 696  * While in the IR it represents a block in terms of control-flow.
 697  */
 698 bool ast_block_codegen(ast_block *self, ast_function *func, bool lvalue, ir_value **out)
 699 {
 700     size_t i;
 701
 702     /* We don't use this
 703      * Note: an ast-representation using the comma-operator
 704      * of the form: (a, b, c) = x should not assign to c...
 705      */
 706     (void)lvalue;
 707
 708     /* output is NULL at first, we'll have each expression
 709      * assign to out output, thus, a comma-operator represention
 710      * using an ast_block will return the last generated value,
 711      * so: (b, c) + a  executed both b and c, and returns c,
 712      * which is then added to a.
 713      */
 714     *out = NULL;
 715
 716     /* generate locals */
 717     for (i = 0; i < self->locals_count; ++i)
 718     {
 719         if (!ast_local_codegen(self->locals[i], func->ir_func, false))
 720             return false;
 721     }
 722
 723     for (i = 0; i < self->exprs_count; ++i)
 724     {
 725         ast_expression_codegen *gen = self->exprs[i]->expression.codegen;
 726         if (!(*gen)(self->exprs[i], func, false, out))
 727             return false;
 728     }
 729
 730     return true;
 731 }
 732
 733 bool ast_store_codegen(ast_store *self, ast_function *func, bool lvalue, ir_value **out)
 734 {
 735     ast_expression_codegen *cgen;
 736     ir_value *left, *right;
 737
 738     cgen = self->dest->expression.codegen;
 739     /* lvalue! */
 740     if (!(*cgen)((ast_expression*)(self->dest), func, true, &left))
 741         return false;
 742
 743     cgen = self->source->expression.codegen;
 744     /* rvalue! */
 745     if (!(*cgen)((ast_expression*)(self->source), func, false, &right))
 746         return false;
 747
 748     if (!ir_block_create_store_op(func->curblock, self->op, left, right))
 749         return false;
 750
 751     /* Theoretically, an assinment returns its left side as an
 752      * lvalue, if we don't need an lvalue though, we return
 753      * the right side as an rvalue, otherwise we have to
 754      * somehow know whether or not we need to dereference the pointer
 755      * on the left side - that is: OP_LOAD if it was an address.
 756      * Also: in original QC we cannot OP_LOADP *anyway*.
 757      */
 758     *out = (lvalue ? left : right);
 759
 760     return true;
 761 }
 762
 763 bool ast_binary_codegen(ast_binary *self, ast_function *func, bool lvalue, ir_value **out)
 764 {
 765     ast_expression_codegen *cgen;
 766     ir_value *left, *right;
 767
 768     /* In the context of a binary operation, we can disregard
 769      * the lvalue flag.
 770      */
 771      (void)lvalue;
 772
 773     cgen = self->left->expression.codegen;
 774     /* lvalue! */
 775     if (!(*cgen)((ast_expression*)(self->left), func, false, &left))
 776         return false;
 777
 778     cgen = self->right->expression.codegen;
 779     /* rvalue! */
 780     if (!(*cgen)((ast_expression*)(self->right), func, false, &right))
 781         return false;
 782
 783     *out = ir_block_create_binop(func->curblock, ast_function_label(func, "bin"),
 784                                  self->op, left, right);
 785     if (!*out)
 786         return false;
 787
 788     return true;
 789 }
 790
 791 bool ast_unary_codegen(ast_unary *self, ast_function *func, bool lvalue, ir_value **out)
 792 {
 793     ast_expression_codegen *cgen;
 794     ir_value *operand;
 795
 796     /* In the context of a unary operation, we can disregard
 797      * the lvalue flag.
 798      */
 799     (void)lvalue;
 800
 801     cgen = self->operand->expression.codegen;
 802     /* lvalue! */
 803     if (!(*cgen)((ast_expression*)(self->operand), func, false, &operand))
 804         return false;
 805
 806     *out = ir_block_create_unary(func->curblock, ast_function_label(func, "unary"),
 807                                  self->op, operand);
 808     if (!*out)
 809         return false;
 810
 811     return true;
 812 }
 813
 814 bool ast_return_codegen(ast_return *self, ast_function *func, bool lvalue, ir_value **out)
 815 {
 816     ast_expression_codegen *cgen;
 817     ir_value *operand;
 818
 819     /* In the context of a return operation, we can disregard
 820      * the lvalue flag.
 821      */
 822     (void)lvalue;
 823
 824     cgen = self->operand->expression.codegen;
 825     /* lvalue! */
 826     if (!(*cgen)((ast_expression*)(self->operand), func, false, &operand))
 827         return false;
 828
 829     if (!ir_block_create_return(func->curblock, operand))
 830         return false;
 831
 832     return true;
 833 }
 834
 835 bool ast_entfield_codegen(ast_entfield *self, ast_function *func, bool lvalue, ir_value **out)
 836 {
 837     ast_expression_codegen *cgen;
 838     ir_value *ent, *field;
 839
 840     /* This function needs to take the 'lvalue' flag into account!
 841      * As lvalue we provide a field-pointer, as rvalue we provide the
 842      * value in a temp.
 843      */
 844
 845     cgen = self->entity->expression.codegen;
 846     if (!(*cgen)((ast_expression*)(self->entity), func, false, &ent))
 847         return false;
 848
 849     cgen = self->field->expression.codegen;
 850     if (!(*cgen)((ast_expression*)(self->field), func, false, &field))
 851         return false;
 852
 853     if (lvalue) {
 854         /* address! */
 855         *out = ir_block_create_fieldaddress(func->curblock, ast_function_label(func, "efa"),
 856                                             ent, field);
 857     } else {
 858         *out = ir_block_create_load_from_ent(func->curblock, ast_function_label(func, "efv"),
 859                                              ent, field, self->expression.vtype);
 860     }
 861     if (!*out)
 862         return false;
 863
 864     /* Hm that should be it... */
 865     return true;
 866 }
 867
 868 bool ast_ifthen_codegen(ast_ifthen *self, ast_function *func, bool lvalue, ir_value **out)
 869 {
 870     ast_expression_codegen *cgen;
 871
 872     ir_value *condval;
 873     ir_value *dummy;
 874
 875     ir_block *cond = func->curblock;
 876     ir_block *ontrue;
 877     ir_block *onfalse;
 878     ir_block *merge;
 879
 880     /* We don't output any value, thus also don't care about r/lvalue */
 881     (void)out;
 882     (void)lvalue;
 883
 884     /* generate the condition */
 885     func->curblock = cond;
 886     cgen = self->cond->expression.codegen;
 887     if (!(*cgen)((ast_expression*)(self->cond), func, false, &condval))
 888         return false;
 889
 890     /* on-true path */
 891
 892     if (self->on_true) {
 893         /* create on-true block */
 894         ontrue = ir_function_create_block(func->ir_func, ast_function_label(func, "ontrue"));
 895         if (!ontrue)
 896             return false;
 897
 898         /* enter the block */
 899         func->curblock = ontrue;
 900
 901         /* generate */
 902         cgen = self->on_true->expression.codegen;
 903         if (!(*cgen)((ast_expression*)(self->on_true), func, false, &dummy))
 904             return false;
 905     } else
 906         ontrue = NULL;
 907
 908     /* on-false path */
 909     if (self->on_false) {
 910         /* create on-false block */
 911         onfalse = ir_function_create_block(func->ir_func, ast_function_label(func, "onfalse"));
 912         if (!onfalse)
 913             return false;
 914
 915         /* enter the block */
 916         func->curblock = onfalse;
 917
 918         /* generate */
 919         cgen = self->on_false->expression.codegen;
 920         if (!(*cgen)((ast_expression*)(self->on_false), func, false, &dummy))
 921             return false;
 922     } else
 923         onfalse = NULL;
 924
 925     /* Merge block were they all merge in to */
 926     merge = ir_function_create_block(func->ir_func, ast_function_label(func, "endif"));
 927     if (!merge)
 928         return false;
 929
 930     /* add jumps ot the merge block */
 931     if (ontrue && !ir_block_create_jump(ontrue, merge))
 932         return false;
 933     if (onfalse && !ir_block_create_jump(onfalse, merge))
 934         return false;
 935
 936     /* we create the if here, that way all blocks are ordered :)
 937      */
 938     if (!ir_block_create_if(cond, condval,
 939                             (ontrue  ? ontrue  : merge),
 940                             (onfalse ? onfalse : merge)))
 941     {
 942         return false;
 943     }
 944
 945     /* Now enter the merge block */
 946     func->curblock = merge;
 947
 948     return true;
 949 }
 950
 951 bool ast_ternary_codegen(ast_ternary *self, ast_function *func, bool lvalue, ir_value **out)
 952 {
 953     ast_expression_codegen *cgen;
 954
 955     ir_value *condval;
 956     ir_value *trueval, *falseval;
 957     ir_instr *phi;
 958
 959     ir_block *cond = func->curblock;
 960     ir_block *ontrue;
 961     ir_block *onfalse;
 962     ir_block *merge;
 963
 964     /* In theory it shouldn't be possible to pass through a node twice, but
 965      * in case we add any kind of optimization pass for the AST itself, it
 966      * may still happen, thus we remember a created ir_value and simply return one
 967      * if it already exists.
 968      */
 969     if (self->phi_out) {
 970         *out = self->phi_out;
 971         return true;
 972     }
 973
 974     /* Ternary can never create an lvalue... */
 975     if (lvalue)
 976         return false;
 977
 978     /* In the following, contraty to ast_ifthen, we assume both paths exist. */
 979
 980     /* generate the condition */
 981     func->curblock = cond;
 982     cgen = self->cond->expression.codegen;
 983     if (!(*cgen)((ast_expression*)(self->cond), func, false, &condval))
 984         return false;
 985
 986     /* create on-true block */
 987     ontrue = ir_function_create_block(func->ir_func, ast_function_label(func, "tern_T"));
 988     if (!ontrue)
 989         return false;
 990     else
 991     {
 992         /* enter the block */
 993         func->curblock = ontrue;
 994
 995         /* generate */
 996         cgen = self->on_true->expression.codegen;
 997         if (!(*cgen)((ast_expression*)(self->on_true), func, false, &trueval))
 998             return false;
 999     }
1000
1001     /* create on-false block */
1002     onfalse = ir_function_create_block(func->ir_func, ast_function_label(func, "tern_F"));
1003     if (!onfalse)
1004         return false;
1005     else
1006     {
1007         /* enter the block */
1008         func->curblock = onfalse;
1009
1010         /* generate */
1011         cgen = self->on_false->expression.codegen;
1012         if (!(*cgen)((ast_expression*)(self->on_false), func, false, &falseval))
1013             return false;
1014     }
1015
1016     /* create merge block */
1017     merge = ir_function_create_block(func->ir_func, ast_function_label(func, "tern_out"));
1018     if (!merge)
1019         return false;
1020     /* jump to merge block */
1021     if (!ir_block_create_jump(ontrue, merge))
1022         return false;
1023     if (!ir_block_create_jump(onfalse, merge))
1024         return false;
1025
1026     /* create if instruction */
1027     if (!ir_block_create_if(cond, condval, ontrue, onfalse))
1028         return false;
1029
1030     /* Now enter the merge block */
1031     func->curblock = merge;
1032
1033     /* Here, now, we need a PHI node
1034      * but first some sanity checking...
1035      */
1036     if (trueval->vtype != falseval->vtype) {
1037         /* error("ternary with different types on the two sides"); */
1038         return false;
1039     }
1040
1041     /* create PHI */
1042     phi = ir_block_create_phi(merge, ast_function_label(func, "phi"), trueval->vtype);
1043     if (!phi ||
1044         !ir_phi_add(phi, ontrue,  trueval) ||
1045         !ir_phi_add(phi, onfalse, falseval))
1046     {
1047         return false;
1048     }
1049
1050     self->phi_out = ir_phi_value(phi);
1051     *out = self->phi_out;
1052
1053     return true;
1054 }
1055
1056 bool ast_loop_codegen(ast_loop *self, ast_function *func, bool lvalue, ir_value **out)
1057 {
1058     ast_expression_codegen *cgen;
1059
1060     ir_value *dummy      = NULL;
1061     ir_value *precond    = NULL;
1062     ir_value *postcond   = NULL;
1063
1064     /* Since we insert some jumps "late" so we have blocks
1065      * ordered "nicely", we need to keep track of the actual end-blocks
1066      * of expressions to add the jumps to.
1067      */
1068     ir_block *bbody      = NULL, *end_bbody      = NULL;
1069     ir_block *bprecond   = NULL, *end_bprecond   = NULL;
1070     ir_block *bpostcond  = NULL, *end_bpostcond  = NULL;
1071     ir_block *bincrement = NULL, *end_bincrement = NULL;
1072     ir_block *bout       = NULL, *bin            = NULL;
1073
1074     /* let's at least move the outgoing block to the end */
1075     size_t    bout_id;
1076
1077     /* 'break' and 'continue' need to be able to find the right blocks */
1078     ir_block *bcontinue     = NULL;
1079     ir_block *bbreak        = NULL;
1080
1081     ir_block *old_bcontinue = NULL;
1082     ir_block *old_bbreak    = NULL;
1083
1084     ir_block *tmpblock      = NULL;
1085
1086     (void)lvalue;
1087     (void)out;
1088
1089     /* NOTE:
1090      * Should we ever need some kind of block ordering, better make this function
1091      * move blocks around than write a block ordering algorithm later... after all
1092      * the ast and ir should work together, not against each other.
1093      */
1094
1095     /* initexpr doesn't get its own block, it's pointless, it could create more blocks
1096      * anyway if for example it contains a ternary.
1097      */
1098     if (self->initexpr)
1099     {
1100         cgen = self->initexpr->expression.codegen;
1101         if (!(*cgen)((ast_expression*)(self->initexpr), func, false, &dummy))
1102             return false;
1103     }
1104
1105     /* Store the block from which we enter this chaos */
1106     bin = func->curblock;
1107
1108     /* The pre-loop condition needs its own block since we
1109      * need to be able to jump to the start of that expression.
1110      */
1111     if (self->precond)
1112     {
1113         bprecond = ir_function_create_block(func->ir_func, ast_function_label(func, "pre_loop_cond"));
1114         if (!bprecond)
1115             return false;
1116
1117         /* the pre-loop-condition the least important place to 'continue' at */
1118         bcontinue = bprecond;
1119
1120         /* enter */
1121         func->curblock = bprecond;
1122
1123         /* generate */
1124         cgen = self->precond->expression.codegen;
1125         if (!(*cgen)((ast_expression*)(self->precond), func, false, &precond))
1126             return false;
1127
1128         end_bprecond = func->curblock;
1129     } else {
1130         bprecond = end_bprecond = NULL;
1131     }
1132
1133     /* Now the next blocks won't be ordered nicely, but we need to
1134      * generate them this early for 'break' and 'continue'.
1135      */
1136     if (self->increment) {
1137         bincrement = ir_function_create_block(func->ir_func, ast_function_label(func, "loop_increment"));
1138         if (!bincrement)
1139             return false;
1140         bcontinue = bincrement; /* increment comes before the pre-loop-condition */
1141     } else {
1142         bincrement = end_bincrement = NULL;
1143     }
1144
1145     if (self->postcond) {
1146         bpostcond = ir_function_create_block(func->ir_func, ast_function_label(func, "post_loop_cond"));
1147         if (!bpostcond)
1148             return false;
1149         bcontinue = bpostcond; /* postcond comes before the increment */
1150     } else {
1151         bpostcond = end_bpostcond = NULL;
1152     }
1153
1154     bout_id = func->ir_func->blocks_count;
1155     bout = ir_function_create_block(func->ir_func, ast_function_label(func, "after_loop"));
1156     if (!bout)
1157         return false;
1158     bbreak = bout;
1159
1160     /* The loop body... */
1161     if (self->body)
1162     {
1163         bbody = ir_function_create_block(func->ir_func, ast_function_label(func, "loop_body"));
1164         if (!bbody)
1165             return false;
1166
1167         /* enter */
1168         func->curblock = bbody;
1169
1170         old_bbreak          = func->breakblock;
1171         old_bcontinue       = func->continueblock;
1172         func->breakblock    = bbreak;
1173         func->continueblock = bcontinue;
1174
1175         /* generate */
1176         cgen = self->body->expression.codegen;
1177         if (!(*cgen)((ast_expression*)(self->body), func, false, &dummy))
1178             return false;
1179
1180         end_bbody = func->curblock;
1181         func->breakblock    = old_bbreak;
1182         func->continueblock = old_bcontinue;
1183     }
1184
1185     /* post-loop-condition */
1186     if (self->postcond)
1187     {
1188         /* enter */
1189         func->curblock = bpostcond;
1190
1191         /* generate */
1192         cgen = self->postcond->expression.codegen;
1193         if (!(*cgen)((ast_expression*)(self->postcond), func, false, &postcond))
1194             return false;
1195
1196         end_bpostcond = func->curblock;
1197     }
1198
1199     /* The incrementor */
1200     if (self->increment)
1201     {
1202         /* enter */
1203         func->curblock = bincrement;
1204
1205         /* generate */
1206         cgen = self->increment->expression.codegen;
1207         if (!(*cgen)((ast_expression*)(self->increment), func, false, &dummy))
1208             return false;
1209
1210         end_bincrement = func->curblock;
1211     }
1212
1213     /* In any case now, we continue from the outgoing block */
1214     func->curblock = bout;
1215
1216     /* Now all blocks are in place */
1217     /* From 'bin' we jump to whatever comes first */
1218     if      (bprecond)   tmpblock = bprecond;
1219     else if (bbody)      tmpblock = bbody;
1220     else if (bpostcond)  tmpblock = bpostcond;
1221     else                 tmpblock = bout;
1222     if (!ir_block_create_jump(bin, tmpblock))
1223         return false;
1224
1225     /* From precond */
1226     if (bprecond)
1227     {
1228         ir_block *ontrue, *onfalse;
1229         if      (bbody)      ontrue = bbody;
1230         else if (bincrement) ontrue = bincrement;
1231         else if (bpostcond)  ontrue = bpostcond;
1232         else                 ontrue = bprecond;
1233         onfalse = bout;
1234         if (!ir_block_create_if(end_bprecond, precond, ontrue, onfalse))
1235             return false;
1236     }
1237
1238     /* from body */
1239     if (bbody)
1240     {
1241         if      (bincrement) tmpblock = bincrement;
1242         else if (bpostcond)  tmpblock = bpostcond;
1243         else if (bprecond)   tmpblock = bprecond;
1244         else                 tmpblock = bout;
1245         if (!ir_block_create_jump(end_bbody, tmpblock))
1246             return false;
1247     }
1248
1249     /* from increment */
1250     if (bincrement)
1251     {
1252         if      (bpostcond)  tmpblock = bpostcond;
1253         else if (bprecond)   tmpblock = bprecond;
1254         else if (bbody)      tmpblock = bbody;
1255         else                 tmpblock = bout;
1256         if (!ir_block_create_jump(end_bincrement, tmpblock))
1257             return false;
1258     }
1259
1260     /* from postcond */
1261     if (bpostcond)
1262     {
1263         ir_block *ontrue, *onfalse;
1264         if      (bprecond)   ontrue = bprecond;
1265         else if (bbody)      ontrue = bbody;
1266         else if (bincrement) ontrue = bincrement;
1267         else                 ontrue = bpostcond;
1268         onfalse = bout;
1269         if (!ir_block_create_if(end_bpostcond, postcond, ontrue, onfalse))
1270             return false;
1271     }
1272
1273     /* Move 'bout' to the end */
1274     if (!ir_function_blocks_remove(func->ir_func, bout_id) ||
1275         !ir_function_blocks_add(func->ir_func, bout))
1276     {
1277         ir_block_delete(bout);
1278         return false;
1279     }
1280
1281     return true;
1282 }
1283
1284 bool ast_call_codegen(ast_call *self, ast_function *func, bool lvalue, ir_value **out)
1285 {
1286     ast_expression_codegen *cgen;
1287     ir_value_vector         params;
1288     ir_instr               *callinstr;
1289     size_t i;
1290
1291     ir_value *funval = NULL;
1292
1293     /* return values are never rvalues */
1294     (void)lvalue;
1295
1296     cgen = self->func->expression.codegen;
1297     if (!(*cgen)((ast_expression*)(self->func), func, false, &funval))
1298         return false;
1299     if (!funval)
1300         return false;
1301
1302     MEM_VECTOR_INIT(&params, v);
1303
1304     /* parameters */
1305     for (i = 0; i < self->params_count; ++i)
1306     {
1307         ir_value *param;
1308         ast_expression *expr = self->params[i];
1309
1310         cgen = expr->expression.codegen;
1311         if (!(*cgen)(expr, func, false, &param))
1312             goto error;
1313         if (!param)
1314             goto error;
1315         if (!ir_value_vector_v_add(&params, param))
1316             goto error;
1317     }
1318
1319     callinstr = ir_block_create_call(func->curblock, ast_function_label(func, "call"), funval);
1320     if (!callinstr)
1321         goto error;
1322
1323     for (i = 0; i < params.v_count; ++i) {
1324         if (!ir_call_param(callinstr, params.v[i]))
1325             goto error;
1326     }
1327
1328     *out = ir_call_value(callinstr);
1329
1330     return true;
1331 error:
1332     MEM_VECTOR_CLEAR(&params, v);
1333     return false;
1334 }