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