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     MEM_VECTOR_INIT(self, params);
 403
 404     self->labelcount = 0;
 405     self->builtin = 0;
 406
 407     self->ir_func = NULL;
 408     self->curblock = NULL;
 409
 410     self->breakblock    = NULL;
 411     self->continueblock = NULL;
 412
 413     vtype->isconst = true;
 414     vtype->constval.vfunc = self;
 415
 416     return self;
 417 }
 418
 419 MEM_VEC_FUNCTIONS(ast_function, ast_block*, blocks)
 420 MEM_VEC_FUNCTIONS(ast_function, ast_value*, params)
 421
 422 void ast_function_delete(ast_function *self)
 423 {
 424     size_t i;
 425     if (self->name)
 426         mem_d((void*)self->name);
 427     if (self->vtype) {
 428         /* ast_value_delete(self->vtype); */
 429         self->vtype->isconst = false;
 430         self->vtype->constval.vfunc = NULL;
 431         /* We use unref - if it was stored in a global table it is supposed
 432          * to be deleted from *there*
 433          */
 434         ast_unref(self->vtype);
 435     }
 436     for (i = 0; i < self->blocks_count; ++i)
 437         ast_delete(self->blocks[i]);
 438     MEM_VECTOR_CLEAR(self, blocks);
 439     for (i = 0; i < self->params_count; ++i)
 440         ast_delete(self->params[i]);
 441     MEM_VECTOR_CLEAR(self, params);
 442     mem_d(self);
 443 }
 444
 445 static void ast_util_hexitoa(char *buf, size_t size, unsigned int num)
 446 {
 447     unsigned int base = 10;
 448 #define checknul() do { if (size == 1) { *buf = 0; return; } } while (0)
 449 #define addch(x) do { *buf++ = (x); --size; checknul(); } while (0)
 450     if (size < 1)
 451         return;
 452     checknul();
 453     if (!num)
 454         addch('0');
 455     else {
 456         while (num)
 457         {
 458             int digit = num % base;
 459             num /= base;
 460             addch('0' + digit);
 461         }
 462     }
 463
 464     *buf = 0;
 465 #undef addch
 466 #undef checknul
 467 }
 468
 469 const char* ast_function_label(ast_function *self, const char *prefix)
 470 {
 471     size_t id = (self->labelcount++);
 472     size_t len = strlen(prefix);
 473     strncpy(self->labelbuf, prefix, sizeof(self->labelbuf));
 474     ast_util_hexitoa(self->labelbuf + len, sizeof(self->labelbuf)-len, id);
 475     return self->labelbuf;
 476 }
 477
 478 /*********************************************************************/
 479 /* AST codegen part
 480  * by convention you must never pass NULL to the 'ir_value **out'
 481  * parameter. If you really don't care about the output, pass a dummy.
 482  * But I can't imagine a pituation where the output is truly unnecessary.
 483  */
 484
 485 bool ast_value_codegen(ast_value *self, ast_function *func, bool lvalue, ir_value **out)
 486 {
 487     /* NOTE: This is the codegen for a variable used in an expression.
 488      * It is not the codegen to generate the value. For this purpose,
 489      * ast_local_codegen and ast_global_codegen are to be used before this
 490      * is executed. ast_function_codegen should take care of its locals,
 491      * and the ast-user should take care of ast_global_codegen to be used
 492      * on all the globals.
 493      */
 494     if (!self->ir_v) {
 495         printf("ast_value used before generated (%s)\n", self->name);
 496         return false;
 497     }
 498     *out = self->ir_v;
 499     return true;
 500 }
 501
 502 bool ast_global_codegen(ast_value *self, ir_builder *ir)
 503 {
 504     ir_value *v = NULL;
 505     if (self->isconst && self->expression.vtype == TYPE_FUNCTION)
 506     {
 507         ir_function *func = ir_builder_create_function(ir, self->name, self->expression.next->expression.vtype);
 508         if (!func)
 509             return false;
 510
 511         self->constval.vfunc->ir_func = func;
 512         self->ir_v = func->value;
 513         /* The function is filled later on ast_function_codegen... */
 514         return true;
 515     }
 516
 517     v = ir_builder_create_global(ir, self->name, self->expression.vtype);
 518     if (!v)
 519         return false;
 520
 521     if (self->isconst) {
 522         switch (self->expression.vtype)
 523         {
 524             case TYPE_FLOAT:
 525                 if (!ir_value_set_float(v, self->constval.vfloat))
 526                     goto error;
 527                 break;
 528             case TYPE_VECTOR:
 529                 if (!ir_value_set_vector(v, self->constval.vvec))
 530                     goto error;
 531                 break;
 532             case TYPE_STRING:
 533                 if (!ir_value_set_string(v, self->constval.vstring))
 534                     goto error;
 535                 break;
 536             case TYPE_FUNCTION:
 537                 printf("global of type function not properly generated\n");
 538                 goto error;
 539                 /* Cannot generate an IR value for a function,
 540                  * need a pointer pointing to a function rather.
 541                  */
 542             default:
 543                 printf("TODO: global constant type %i\n", self->expression.vtype);
 544                 break;
 545         }
 546     }
 547
 548     /* link us to the ir_value */
 549     self->ir_v = v;
 550     return true;
 551
 552 error: /* clean up */
 553     ir_value_delete(v);
 554     return false;
 555 }
 556
 557 bool ast_local_codegen(ast_value *self, ir_function *func)
 558 {
 559     ir_value *v = NULL;
 560     if (self->isconst && self->expression.vtype == TYPE_FUNCTION)
 561     {
 562         /* Do we allow local functions? I think not...
 563          * this is NOT a function pointer atm.
 564          */
 565         return false;
 566     }
 567
 568     v = ir_function_create_local(func, self->name, self->expression.vtype);
 569     if (!v)
 570         return false;
 571
 572     /* A constant local... hmmm...
 573      * I suppose the IR will have to deal with this
 574      */
 575     if (self->isconst) {
 576         switch (self->expression.vtype)
 577         {
 578             case TYPE_FLOAT:
 579                 if (!ir_value_set_float(v, self->constval.vfloat))
 580                     goto error;
 581                 break;
 582             case TYPE_VECTOR:
 583                 if (!ir_value_set_vector(v, self->constval.vvec))
 584                     goto error;
 585                 break;
 586             case TYPE_STRING:
 587                 if (!ir_value_set_string(v, self->constval.vstring))
 588                     goto error;
 589                 break;
 590             default:
 591                 printf("TODO: global constant type %i\n", self->expression.vtype);
 592                 break;
 593         }
 594     }
 595
 596     /* link us to the ir_value */
 597     self->ir_v = v;
 598     return true;
 599
 600 error: /* clean up */
 601     ir_value_delete(v);
 602     return false;
 603 }
 604
 605 bool ast_function_codegen(ast_function *self, ir_builder *ir)
 606 {
 607     ir_function *irf;
 608     ir_value    *dummy;
 609     size_t    i;
 610
 611     irf = self->ir_func;
 612     if (!irf) {
 613         printf("ast_function's related ast_value was not generated yet\n");
 614         return false;
 615     }
 616
 617     for (i = 0; i < self->params_count; ++i)
 618     {
 619         if (!ir_function_params_add(irf, self->params[i]->expression.vtype))
 620             return false;
 621     }
 622
 623     if (self->builtin) {
 624         irf->builtin = self->builtin;
 625         return true;
 626     }
 627
 628     self->curblock = ir_function_create_block(irf, "entry");
 629     if (!self->curblock)
 630         return false;
 631
 632     for (i = 0; i < self->blocks_count; ++i) {
 633         ast_expression_codegen *gen = self->blocks[i]->expression.codegen;
 634         if (!(*gen)((ast_expression*)self->blocks[i], self, false, &dummy))
 635             return false;
 636     }
 637
 638     /* TODO: check return types */
 639     if (!self->curblock->is_return)
 640     {
 641         if (!self->vtype->expression.next ||
 642             self->vtype->expression.next->expression.vtype == TYPE_VOID)
 643             return ir_block_create_return(self->curblock, NULL);
 644         else
 645         {
 646             /* error("missing return"); */
 647             return false;
 648         }
 649     }
 650     return true;
 651 }
 652
 653 /* Note, you will not see ast_block_codegen generate ir_blocks.
 654  * To the AST and the IR, blocks are 2 different things.
 655  * In the AST it represents a block of code, usually enclosed in
 656  * curly braces {...}.
 657  * While in the IR it represents a block in terms of control-flow.
 658  */
 659 bool ast_block_codegen(ast_block *self, ast_function *func, bool lvalue, ir_value **out)
 660 {
 661     size_t i;
 662
 663     /* We don't use this
 664      * Note: an ast-representation using the comma-operator
 665      * of the form: (a, b, c) = x should not assign to c...
 666      */
 667     (void)lvalue;
 668
 669     /* output is NULL at first, we'll have each expression
 670      * assign to out output, thus, a comma-operator represention
 671      * using an ast_block will return the last generated value,
 672      * so: (b, c) + a  executed both b and c, and returns c,
 673      * which is then added to a.
 674      */
 675     *out = NULL;
 676
 677     /* generate locals */
 678     for (i = 0; i < self->locals_count; ++i)
 679     {
 680         if (!ast_local_codegen(self->locals[i], func->ir_func))
 681             return false;
 682     }
 683
 684     for (i = 0; i < self->exprs_count; ++i)
 685     {
 686         ast_expression_codegen *gen = self->exprs[i]->expression.codegen;
 687         if (!(*gen)(self->exprs[i], func, false, out))
 688             return false;
 689     }
 690
 691     return true;
 692 }
 693
 694 bool ast_store_codegen(ast_store *self, ast_function *func, bool lvalue, ir_value **out)
 695 {
 696     ast_expression_codegen *cgen;
 697     ir_value *left, *right;
 698
 699     cgen = self->dest->expression.codegen;
 700     /* lvalue! */
 701     if (!(*cgen)((ast_expression*)(self->dest), func, true, &left))
 702         return false;
 703
 704     cgen = self->source->expression.codegen;
 705     /* rvalue! */
 706     if (!(*cgen)((ast_expression*)(self->source), func, false, &right))
 707         return false;
 708
 709     if (!ir_block_create_store_op(func->curblock, self->op, left, right))
 710         return false;
 711
 712     /* Theoretically, an assinment returns its left side as an
 713      * lvalue, if we don't need an lvalue though, we return
 714      * the right side as an rvalue, otherwise we have to
 715      * somehow know whether or not we need to dereference the pointer
 716      * on the left side - that is: OP_LOAD if it was an address.
 717      * Also: in original QC we cannot OP_LOADP *anyway*.
 718      */
 719     *out = (lvalue ? left : right);
 720
 721     return true;
 722 }
 723
 724 bool ast_binary_codegen(ast_binary *self, ast_function *func, bool lvalue, ir_value **out)
 725 {
 726     ast_expression_codegen *cgen;
 727     ir_value *left, *right;
 728
 729     /* In the context of a binary operation, we can disregard
 730      * the lvalue flag.
 731      */
 732      (void)lvalue;
 733
 734     cgen = self->left->expression.codegen;
 735     /* lvalue! */
 736     if (!(*cgen)((ast_expression*)(self->left), func, false, &left))
 737         return false;
 738
 739     cgen = self->right->expression.codegen;
 740     /* rvalue! */
 741     if (!(*cgen)((ast_expression*)(self->right), func, false, &right))
 742         return false;
 743
 744     *out = ir_block_create_binop(func->curblock, ast_function_label(func, "bin"),
 745                                  self->op, left, right);
 746     if (!*out)
 747         return false;
 748
 749     return true;
 750 }
 751
 752 bool ast_entfield_codegen(ast_entfield *self, ast_function *func, bool lvalue, ir_value **out)
 753 {
 754     ast_expression_codegen *cgen;
 755     ir_value *ent, *field;
 756
 757     /* This function needs to take the 'lvalue' flag into account!
 758      * As lvalue we provide a field-pointer, as rvalue we provide the
 759      * value in a temp.
 760      */
 761
 762     cgen = self->entity->expression.codegen;
 763     if (!(*cgen)((ast_expression*)(self->entity), func, false, &ent))
 764         return false;
 765
 766     cgen = self->field->expression.codegen;
 767     if (!(*cgen)((ast_expression*)(self->field), func, false, &field))
 768         return false;
 769
 770     if (lvalue) {
 771         /* address! */
 772         *out = ir_block_create_fieldaddress(func->curblock, ast_function_label(func, "efa"),
 773                                             ent, field);
 774     } else {
 775         *out = ir_block_create_load_from_ent(func->curblock, ast_function_label(func, "efv"),
 776                                              ent, field, self->expression.vtype);
 777     }
 778     if (!*out)
 779         return false;
 780
 781     /* Hm that should be it... */
 782     return true;
 783 }
 784
 785 bool ast_ifthen_codegen(ast_ifthen *self, ast_function *func, bool lvalue, ir_value **out)
 786 {
 787     ast_expression_codegen *cgen;
 788
 789     ir_value *condval;
 790     ir_value *dummy;
 791
 792     ir_block *cond = func->curblock;
 793     ir_block *ontrue;
 794     ir_block *onfalse;
 795     ir_block *merge;
 796
 797     /* We don't output any value, thus also don't care about r/lvalue */
 798     (void)out;
 799     (void)lvalue;
 800
 801     /* generate the condition */
 802     func->curblock = cond;
 803     cgen = self->cond->expression.codegen;
 804     if (!(*cgen)((ast_expression*)(self->cond), func, false, &condval))
 805         return false;
 806
 807     /* on-true path */
 808
 809     if (self->on_true) {
 810         /* create on-true block */
 811         ontrue = ir_function_create_block(func->ir_func, ast_function_label(func, "ontrue"));
 812         if (!ontrue)
 813             return false;
 814
 815         /* enter the block */
 816         func->curblock = ontrue;
 817
 818         /* generate */
 819         cgen = self->on_true->expression.codegen;
 820         if (!(*cgen)((ast_expression*)(self->on_true), func, false, &dummy))
 821             return false;
 822     } else
 823         ontrue = NULL;
 824
 825     /* on-false path */
 826     if (self->on_false) {
 827         /* create on-false block */
 828         onfalse = ir_function_create_block(func->ir_func, ast_function_label(func, "onfalse"));
 829         if (!onfalse)
 830             return false;
 831
 832         /* enter the block */
 833         func->curblock = onfalse;
 834
 835         /* generate */
 836         cgen = self->on_false->expression.codegen;
 837         if (!(*cgen)((ast_expression*)(self->on_false), func, false, &dummy))
 838             return false;
 839     } else
 840         onfalse = NULL;
 841
 842     /* Merge block were they all merge in to */
 843     merge = ir_function_create_block(func->ir_func, ast_function_label(func, "endif"));
 844     if (!merge)
 845         return false;
 846
 847     /* add jumps ot the merge block */
 848     if (ontrue && !ir_block_create_jump(ontrue, merge))
 849         return false;
 850     if (onfalse && !ir_block_create_jump(onfalse, merge))
 851         return false;
 852
 853     /* we create the if here, that way all blocks are ordered :)
 854      */
 855     if (!ir_block_create_if(cond, condval,
 856                             (ontrue  ? ontrue  : merge),
 857                             (onfalse ? onfalse : merge)))
 858     {
 859         return false;
 860     }
 861
 862     /* Now enter the merge block */
 863     func->curblock = merge;
 864
 865     return true;
 866 }
 867
 868 bool ast_ternary_codegen(ast_ternary *self, ast_function *func, bool lvalue, ir_value **out)
 869 {
 870     ast_expression_codegen *cgen;
 871
 872     ir_value *condval;
 873     ir_value *trueval, *falseval;
 874     ir_instr *phi;
 875
 876     ir_block *cond = func->curblock;
 877     ir_block *ontrue;
 878     ir_block *onfalse;
 879     ir_block *merge;
 880
 881     /* In theory it shouldn't be possible to pass through a node twice, but
 882      * in case we add any kind of optimization pass for the AST itself, it
 883      * may still happen, thus we remember a created ir_value and simply return one
 884      * if it already exists.
 885      */
 886     if (self->phi_out) {
 887         *out = self->phi_out;
 888         return true;
 889     }
 890
 891     /* Ternary can never create an lvalue... */
 892     if (lvalue)
 893         return false;
 894
 895     /* In the following, contraty to ast_ifthen, we assume both paths exist. */
 896
 897     /* generate the condition */
 898     func->curblock = cond;
 899     cgen = self->cond->expression.codegen;
 900     if (!(*cgen)((ast_expression*)(self->cond), func, false, &condval))
 901         return false;
 902
 903     /* create on-true block */
 904     ontrue = ir_function_create_block(func->ir_func, ast_function_label(func, "tern_T"));
 905     if (!ontrue)
 906         return false;
 907     else
 908     {
 909         /* enter the block */
 910         func->curblock = ontrue;
 911
 912         /* generate */
 913         cgen = self->on_true->expression.codegen;
 914         if (!(*cgen)((ast_expression*)(self->on_true), func, false, &trueval))
 915             return false;
 916     }
 917
 918     /* create on-false block */
 919     onfalse = ir_function_create_block(func->ir_func, ast_function_label(func, "tern_F"));
 920     if (!onfalse)
 921         return false;
 922     else
 923     {
 924         /* enter the block */
 925         func->curblock = onfalse;
 926
 927         /* generate */
 928         cgen = self->on_false->expression.codegen;
 929         if (!(*cgen)((ast_expression*)(self->on_false), func, false, &falseval))
 930             return false;
 931     }
 932
 933     /* create merge block */
 934     merge = ir_function_create_block(func->ir_func, ast_function_label(func, "tern_out"));
 935     if (!merge)
 936         return false;
 937     /* jump to merge block */
 938     if (!ir_block_create_jump(ontrue, merge))
 939         return false;
 940     if (!ir_block_create_jump(onfalse, merge))
 941         return false;
 942
 943     /* create if instruction */
 944     if (!ir_block_create_if(cond, condval, ontrue, onfalse))
 945         return false;
 946
 947     /* Now enter the merge block */
 948     func->curblock = merge;
 949
 950     /* Here, now, we need a PHI node
 951      * but first some sanity checking...
 952      */
 953     if (trueval->vtype != falseval->vtype) {
 954         /* error("ternary with different types on the two sides"); */
 955         return false;
 956     }
 957
 958     /* create PHI */
 959     phi = ir_block_create_phi(merge, ast_function_label(func, "phi"), trueval->vtype);
 960     if (!phi ||
 961         !ir_phi_add(phi, ontrue,  trueval) ||
 962         !ir_phi_add(phi, onfalse, falseval))
 963     {
 964         return false;
 965     }
 966
 967     self->phi_out = ir_phi_value(phi);
 968     *out = self->phi_out;
 969
 970     return true;
 971 }
 972
 973 bool ast_loop_codegen(ast_loop *self, ast_function *func, bool lvalue, ir_value **out)
 974 {
 975     ast_expression_codegen *cgen;
 976
 977     ir_value *dummy      = NULL;
 978     ir_value *precond    = NULL;
 979     ir_value *postcond   = NULL;
 980
 981     /* Since we insert some jumps "late" so we have blocks
 982      * ordered "nicely", we need to keep track of the actual end-blocks
 983      * of expressions to add the jumps to.
 984      */
 985     ir_block *bbody      = NULL, *end_bbody      = NULL;
 986     ir_block *bprecond   = NULL, *end_bprecond   = NULL;
 987     ir_block *bpostcond  = NULL, *end_bpostcond  = NULL;
 988     ir_block *bincrement = NULL, *end_bincrement = NULL;
 989     ir_block *bout       = NULL, *bin            = NULL;
 990
 991     /* let's at least move the outgoing block to the end */
 992     size_t    bout_id;
 993
 994     /* 'break' and 'continue' need to be able to find the right blocks */
 995     ir_block *bcontinue     = NULL;
 996     ir_block *bbreak        = NULL;
 997
 998     ir_block *old_bcontinue = NULL;
 999     ir_block *old_bbreak    = NULL;
1000
1001     ir_block *tmpblock      = NULL;
1002
1003     (void)lvalue;
1004     (void)out;
1005
1006     /* NOTE:
1007      * Should we ever need some kind of block ordering, better make this function
1008      * move blocks around than write a block ordering algorithm later... after all
1009      * the ast and ir should work together, not against each other.
1010      */
1011
1012     /* initexpr doesn't get its own block, it's pointless, it could create more blocks
1013      * anyway if for example it contains a ternary.
1014      */
1015     if (self->initexpr)
1016     {
1017         cgen = self->initexpr->expression.codegen;
1018         if (!(*cgen)((ast_expression*)(self->initexpr), func, false, &dummy))
1019             return false;
1020     }
1021
1022     /* Store the block from which we enter this chaos */
1023     bin = func->curblock;
1024
1025     /* The pre-loop condition needs its own block since we
1026      * need to be able to jump to the start of that expression.
1027      */
1028     if (self->precond)
1029     {
1030         bprecond = ir_function_create_block(func->ir_func, ast_function_label(func, "pre_loop_cond"));
1031         if (!bprecond)
1032             return false;
1033
1034         /* the pre-loop-condition the least important place to 'continue' at */
1035         bcontinue = bprecond;
1036
1037         /* enter */
1038         func->curblock = bprecond;
1039
1040         /* generate */
1041         cgen = self->precond->expression.codegen;
1042         if (!(*cgen)((ast_expression*)(self->precond), func, false, &precond))
1043             return false;
1044
1045         end_bprecond = func->curblock;
1046     } else {
1047         bprecond = end_bprecond = NULL;
1048     }
1049
1050     /* Now the next blocks won't be ordered nicely, but we need to
1051      * generate them this early for 'break' and 'continue'.
1052      */
1053     if (self->increment) {
1054         bincrement = ir_function_create_block(func->ir_func, ast_function_label(func, "loop_increment"));
1055         if (!bincrement)
1056             return false;
1057         bcontinue = bincrement; /* increment comes before the pre-loop-condition */
1058     } else {
1059         bincrement = end_bincrement = NULL;
1060     }
1061
1062     if (self->postcond) {
1063         bpostcond = ir_function_create_block(func->ir_func, ast_function_label(func, "post_loop_cond"));
1064         if (!bpostcond)
1065             return false;
1066         bcontinue = bpostcond; /* postcond comes before the increment */
1067     } else {
1068         bpostcond = end_bpostcond = NULL;
1069     }
1070
1071     bout_id = func->ir_func->blocks_count;
1072     bout = ir_function_create_block(func->ir_func, ast_function_label(func, "after_loop"));
1073     if (!bout)
1074         return false;
1075     bbreak = bout;
1076
1077     /* The loop body... */
1078     if (self->body)
1079     {
1080         bbody = ir_function_create_block(func->ir_func, ast_function_label(func, "loop_body"));
1081         if (!bbody)
1082             return false;
1083
1084         /* enter */
1085         func->curblock = bbody;
1086
1087         old_bbreak          = func->breakblock;
1088         old_bcontinue       = func->continueblock;
1089         func->breakblock    = bbreak;
1090         func->continueblock = bcontinue;
1091
1092         /* generate */
1093         cgen = self->body->expression.codegen;
1094         if (!(*cgen)((ast_expression*)(self->body), func, false, &dummy))
1095             return false;
1096
1097         end_bbody = func->curblock;
1098         func->breakblock    = old_bbreak;
1099         func->continueblock = old_bcontinue;
1100     }
1101
1102     /* post-loop-condition */
1103     if (self->postcond)
1104     {
1105         /* enter */
1106         func->curblock = bpostcond;
1107
1108         /* generate */
1109         cgen = self->postcond->expression.codegen;
1110         if (!(*cgen)((ast_expression*)(self->postcond), func, false, &postcond))
1111             return false;
1112
1113         end_bpostcond = func->curblock;
1114     }
1115
1116     /* The incrementor */
1117     if (self->increment)
1118     {
1119         /* enter */
1120         func->curblock = bincrement;
1121
1122         /* generate */
1123         cgen = self->increment->expression.codegen;
1124         if (!(*cgen)((ast_expression*)(self->increment), func, false, &dummy))
1125             return false;
1126
1127         end_bincrement = func->curblock;
1128     }
1129
1130     /* In any case now, we continue from the outgoing block */
1131     func->curblock = bout;
1132
1133     /* Now all blocks are in place */
1134     /* From 'bin' we jump to whatever comes first */
1135     if      (bprecond)   tmpblock = bprecond;
1136     else if (bbody)      tmpblock = bbody;
1137     else if (bpostcond)  tmpblock = bpostcond;
1138     else                 tmpblock = bout;
1139     if (!ir_block_create_jump(bin, tmpblock))
1140         return false;
1141
1142     /* From precond */
1143     if (bprecond)
1144     {
1145         ir_block *ontrue, *onfalse;
1146         if      (bbody)      ontrue = bbody;
1147         else if (bincrement) ontrue = bincrement;
1148         else if (bpostcond)  ontrue = bpostcond;
1149         else                 ontrue = bprecond;
1150         onfalse = bout;
1151         if (!ir_block_create_if(end_bprecond, precond, ontrue, onfalse))
1152             return false;
1153     }
1154
1155     /* from body */
1156     if (bbody)
1157     {
1158         if      (bincrement) tmpblock = bincrement;
1159         else if (bpostcond)  tmpblock = bpostcond;
1160         else if (bprecond)   tmpblock = bprecond;
1161         else                 tmpblock = bout;
1162         if (!ir_block_create_jump(end_bbody, tmpblock))
1163             return false;
1164     }
1165
1166     /* from increment */
1167     if (bincrement)
1168     {
1169         if      (bpostcond)  tmpblock = bpostcond;
1170         else if (bprecond)   tmpblock = bprecond;
1171         else if (bbody)      tmpblock = bbody;
1172         else                 tmpblock = bout;
1173         if (!ir_block_create_jump(end_bincrement, tmpblock))
1174             return false;
1175     }
1176
1177     /* from postcond */
1178     if (bpostcond)
1179     {
1180         ir_block *ontrue, *onfalse;
1181         if      (bprecond)   ontrue = bprecond;
1182         else if (bbody)      ontrue = bbody;
1183         else if (bincrement) ontrue = bincrement;
1184         else                 ontrue = bpostcond;
1185         onfalse = bout;
1186         if (!ir_block_create_if(end_bpostcond, postcond, ontrue, onfalse))
1187             return false;
1188     }
1189
1190     /* Move 'bout' to the end */
1191     if (!ir_function_blocks_remove(func->ir_func, bout_id) ||
1192         !ir_function_blocks_add(func->ir_func, bout))
1193     {
1194         ir_block_delete(bout);
1195         return false;
1196     }
1197
1198     return true;
1199 }
1200
1201 bool ast_call_codegen(ast_call *self, ast_function *func, bool lvalue, ir_value **out)
1202 {
1203     ast_expression_codegen *cgen;
1204     ir_value_vector         params;
1205     ir_instr               *callinstr;
1206     size_t i;
1207
1208     ir_value *funval = NULL;
1209
1210     /* return values are never rvalues */
1211     (void)lvalue;
1212
1213     cgen = self->func->expression.codegen;
1214     if (!(*cgen)((ast_expression*)(self->func), func, false, &funval))
1215         return false;
1216     if (!funval)
1217         return false;
1218
1219     MEM_VECTOR_INIT(&params, v);
1220
1221     /* parameters */
1222     for (i = 0; i < self->params_count; ++i)
1223     {
1224         ir_value *param;
1225         ast_expression *expr = self->params[i];
1226
1227         cgen = expr->expression.codegen;
1228         if (!(*cgen)(expr, func, false, &param))
1229             goto error;
1230         if (!param)
1231             goto error;
1232         if (!ir_value_vector_v_add(&params, param))
1233             goto error;
1234     }
1235
1236     callinstr = ir_block_create_call(func->curblock, ast_function_label(func, "call"), funval);
1237     if (!callinstr)
1238         goto error;
1239
1240     for (i = 0; i < params.v_count; ++i) {
1241         if (!ir_call_param(callinstr, params.v[i]))
1242             goto error;
1243     }
1244
1245     *out = ir_call_value(callinstr);
1246
1247     return true;
1248 error:
1249     MEM_VECTOR_CLEAR(&params, v);
1250     return false;
1251 }