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     return self;
 320 }
 321 MEM_VEC_FUNCTIONS(ast_call, ast_expression*, params)
 322
 323 void ast_call_delete(ast_call *self)
 324 {
 325     size_t i;
 326     for (i = 0; i < self->params_count; ++i)
 327         ast_unref(self->params[i]);
 328     MEM_VECTOR_CLEAR(self, params);
 329
 330     if (self->func)
 331         ast_unref(self->func);
 332
 333     ast_expression_delete((ast_expression*)self);
 334     mem_d(self);
 335 }
 336
 337 ast_store* ast_store_new(lex_ctx ctx, int op,
 338                          ast_value *dest, ast_expression *source)
 339 {
 340     ast_instantiate(ast_store, ctx, ast_store_delete);
 341     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_store_codegen);
 342
 343     self->op = op;
 344     self->dest = dest;
 345     self->source = source;
 346
 347     return self;
 348 }
 349
 350 void ast_store_delete(ast_store *self)
 351 {
 352     ast_unref(self->dest);
 353     ast_unref(self->source);
 354     ast_expression_delete((ast_expression*)self);
 355     mem_d(self);
 356 }
 357
 358 ast_block* ast_block_new(lex_ctx ctx)
 359 {
 360     ast_instantiate(ast_block, ctx, ast_block_delete);
 361     ast_expression_init((ast_expression*)self,
 362                         (ast_expression_codegen*)&ast_block_codegen);
 363
 364     MEM_VECTOR_INIT(self, locals);
 365     MEM_VECTOR_INIT(self, exprs);
 366
 367     return self;
 368 }
 369 MEM_VEC_FUNCTIONS(ast_block, ast_value*, locals)
 370 MEM_VEC_FUNCTIONS(ast_block, ast_expression*, exprs)
 371
 372 void ast_block_delete(ast_block *self)
 373 {
 374     size_t i;
 375     for (i = 0; i < self->exprs_count; ++i)
 376         ast_unref(self->exprs[i]);
 377     MEM_VECTOR_CLEAR(self, exprs);
 378     for (i = 0; i < self->locals_count; ++i)
 379         ast_delete(self->locals[i]);
 380     MEM_VECTOR_CLEAR(self, locals);
 381     ast_expression_delete((ast_expression*)self);
 382     mem_d(self);
 383 }
 384
 385 ast_function* ast_function_new(lex_ctx ctx, const char *name, ast_value *vtype)
 386 {
 387     ast_instantiate(ast_function, ctx, ast_function_delete);
 388
 389     if (!vtype ||
 390         vtype->isconst ||
 391         vtype->expression.vtype != TYPE_FUNCTION)
 392     {
 393         mem_d(self);
 394         return NULL;
 395     }
 396
 397     self->vtype = vtype;
 398     self->name = name ? util_strdup(name) : NULL;
 399     MEM_VECTOR_INIT(self, blocks);
 400     MEM_VECTOR_INIT(self, params);
 401
 402     self->labelcount = 0;
 403     self->builtin = 0;
 404
 405     self->ir_func = NULL;
 406     self->curblock = NULL;
 407
 408     self->breakblock    = NULL;
 409     self->continueblock = NULL;
 410
 411     vtype->isconst = true;
 412     vtype->constval.vfunc = self;
 413
 414     return self;
 415 }
 416
 417 MEM_VEC_FUNCTIONS(ast_function, ast_block*, blocks)
 418 MEM_VEC_FUNCTIONS(ast_function, ast_value*, params)
 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     for (i = 0; i < self->params_count; ++i)
 438         ast_delete(self->params[i]);
 439     MEM_VECTOR_CLEAR(self, params);
 440     mem_d(self);
 441 }
 442
 443 static void ast_util_hexitoa(char *buf, size_t size, unsigned int num)
 444 {
 445     unsigned int base = 10;
 446 #define checknul() do { if (size == 1) { *buf = 0; return; } } while (0)
 447 #define addch(x) do { *buf++ = (x); --size; checknul(); } while (0)
 448     if (size < 1)
 449         return;
 450     checknul();
 451     if (!num)
 452         addch('0');
 453     else {
 454         while (num)
 455         {
 456             int digit = num % base;
 457             num /= base;
 458             addch('0' + digit);
 459         }
 460     }
 461
 462     *buf = 0;
 463 #undef addch
 464 #undef checknul
 465 }
 466
 467 const char* ast_function_label(ast_function *self, const char *prefix)
 468 {
 469     size_t id = (self->labelcount++);
 470     size_t len = strlen(prefix);
 471     strncpy(self->labelbuf, prefix, sizeof(self->labelbuf));
 472     ast_util_hexitoa(self->labelbuf + len, sizeof(self->labelbuf)-len, id);
 473     return self->labelbuf;
 474 }
 475
 476 /*********************************************************************/
 477 /* AST codegen part
 478  * by convention you must never pass NULL to the 'ir_value **out'
 479  * parameter. If you really don't care about the output, pass a dummy.
 480  * But I can't imagine a pituation where the output is truly unnecessary.
 481  */
 482
 483 bool ast_value_codegen(ast_value *self, ast_function *func, bool lvalue, ir_value **out)
 484 {
 485     /* NOTE: This is the codegen for a variable used in an expression.
 486      * It is not the codegen to generate the value. For this purpose,
 487      * ast_local_codegen and ast_global_codegen are to be used before this
 488      * is executed. ast_function_codegen should take care of its locals,
 489      * and the ast-user should take care of ast_global_codegen to be used
 490      * on all the globals.
 491      */
 492     if (!self->ir_v)
 493         return false;
 494     *out = self->ir_v;
 495     return true;
 496 }
 497
 498 bool ast_global_codegen(ast_value *self, ir_builder *ir)
 499 {
 500     ir_value *v = NULL;
 501     if (self->isconst && self->expression.vtype == TYPE_FUNCTION)
 502     {
 503         ir_function *func = ir_builder_create_function(ir, self->name, self->expression.next->expression.vtype);
 504         if (!func)
 505             return false;
 506
 507         self->constval.vfunc->ir_func = func;
 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->params_count; ++i)
 613     {
 614         if (!ir_function_params_add(irf, self->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             return ir_block_create_return(self->curblock, NULL);
 639         else
 640         {
 641             /* error("missing return"); */
 642             return false;
 643         }
 644     }
 645     return true;
 646 }
 647
 648 /* Note, you will not see ast_block_codegen generate ir_blocks.
 649  * To the AST and the IR, blocks are 2 different things.
 650  * In the AST it represents a block of code, usually enclosed in
 651  * curly braces {...}.
 652  * While in the IR it represents a block in terms of control-flow.
 653  */
 654 bool ast_block_codegen(ast_block *self, ast_function *func, bool lvalue, ir_value **out)
 655 {
 656     size_t i;
 657
 658     /* We don't use this
 659      * Note: an ast-representation using the comma-operator
 660      * of the form: (a, b, c) = x should not assign to c...
 661      */
 662     (void)lvalue;
 663
 664     /* output is NULL at first, we'll have each expression
 665      * assign to out output, thus, a comma-operator represention
 666      * using an ast_block will return the last generated value,
 667      * so: (b, c) + a  executed both b and c, and returns c,
 668      * which is then added to a.
 669      */
 670     *out = NULL;
 671
 672     /* generate locals */
 673     for (i = 0; i < self->locals_count; ++i)
 674     {
 675         if (!ast_local_codegen(self->locals[i], func->ir_func))
 676             return false;
 677     }
 678
 679     for (i = 0; i < self->exprs_count; ++i)
 680     {
 681         ast_expression_codegen *gen = self->exprs[i]->expression.codegen;
 682         if (!(*gen)(self->exprs[i], func, false, out))
 683             return false;
 684     }
 685
 686     return true;
 687 }
 688
 689 bool ast_store_codegen(ast_store *self, ast_function *func, bool lvalue, ir_value **out)
 690 {
 691     ast_expression_codegen *cgen;
 692     ir_value *left, *right;
 693
 694     cgen = self->dest->expression.codegen;
 695     /* lvalue! */
 696     if (!(*cgen)((ast_expression*)(self->dest), func, true, &left))
 697         return false;
 698
 699     cgen = self->source->expression.codegen;
 700     /* rvalue! */
 701     if (!(*cgen)((ast_expression*)(self->source), func, false, &right))
 702         return false;
 703
 704     if (!ir_block_create_store_op(func->curblock, self->op, left, right))
 705         return false;
 706
 707     /* Theoretically, an assinment returns its left side as an
 708      * lvalue, if we don't need an lvalue though, we return
 709      * the right side as an rvalue, otherwise we have to
 710      * somehow know whether or not we need to dereference the pointer
 711      * on the left side - that is: OP_LOAD if it was an address.
 712      * Also: in original QC we cannot OP_LOADP *anyway*.
 713      */
 714     *out = (lvalue ? left : right);
 715
 716     return true;
 717 }
 718
 719 bool ast_binary_codegen(ast_binary *self, ast_function *func, bool lvalue, ir_value **out)
 720 {
 721     ast_expression_codegen *cgen;
 722     ir_value *left, *right;
 723
 724     /* In the context of a binary operation, we can disregard
 725      * the lvalue flag.
 726      */
 727      (void)lvalue;
 728
 729     cgen = self->left->expression.codegen;
 730     /* lvalue! */
 731     if (!(*cgen)((ast_expression*)(self->left), func, false, &left))
 732         return false;
 733
 734     cgen = self->right->expression.codegen;
 735     /* rvalue! */
 736     if (!(*cgen)((ast_expression*)(self->right), func, false, &right))
 737         return false;
 738
 739     *out = ir_block_create_binop(func->curblock, ast_function_label(func, "bin"),
 740                                  self->op, left, right);
 741     if (!*out)
 742         return false;
 743
 744     return true;
 745 }
 746
 747 bool ast_entfield_codegen(ast_entfield *self, ast_function *func, bool lvalue, ir_value **out)
 748 {
 749     ast_expression_codegen *cgen;
 750     ir_value *ent, *field;
 751
 752     /* This function needs to take the 'lvalue' flag into account!
 753      * As lvalue we provide a field-pointer, as rvalue we provide the
 754      * value in a temp.
 755      */
 756
 757     cgen = self->entity->expression.codegen;
 758     if (!(*cgen)((ast_expression*)(self->entity), func, false, &ent))
 759         return false;
 760
 761     cgen = self->field->expression.codegen;
 762     if (!(*cgen)((ast_expression*)(self->field), func, false, &field))
 763         return false;
 764
 765     if (lvalue) {
 766         /* address! */
 767         *out = ir_block_create_fieldaddress(func->curblock, ast_function_label(func, "efa"),
 768                                             ent, field);
 769     } else {
 770         *out = ir_block_create_load_from_ent(func->curblock, ast_function_label(func, "efv"),
 771                                              ent, field, self->expression.vtype);
 772     }
 773     if (!*out)
 774         return false;
 775
 776     /* Hm that should be it... */
 777     return true;
 778 }
 779
 780 bool ast_ifthen_codegen(ast_ifthen *self, ast_function *func, bool lvalue, ir_value **out)
 781 {
 782     ast_expression_codegen *cgen;
 783
 784     ir_value *condval;
 785     ir_value *dummy;
 786
 787     ir_block *cond = func->curblock;
 788     ir_block *ontrue;
 789     ir_block *onfalse;
 790     ir_block *merge;
 791
 792     /* We don't output any value, thus also don't care about r/lvalue */
 793     (void)out;
 794     (void)lvalue;
 795
 796     /* generate the condition */
 797     func->curblock = cond;
 798     cgen = self->cond->expression.codegen;
 799     if (!(*cgen)((ast_expression*)(self->cond), func, false, &condval))
 800         return false;
 801
 802     /* on-true path */
 803
 804     if (self->on_true) {
 805         /* create on-true block */
 806         ontrue = ir_function_create_block(func->ir_func, ast_function_label(func, "ontrue"));
 807         if (!ontrue)
 808             return false;
 809
 810         /* enter the block */
 811         func->curblock = ontrue;
 812
 813         /* generate */
 814         cgen = self->on_true->expression.codegen;
 815         if (!(*cgen)((ast_expression*)(self->on_true), func, false, &dummy))
 816             return false;
 817     } else
 818         ontrue = NULL;
 819
 820     /* on-false path */
 821     if (self->on_false) {
 822         /* create on-false block */
 823         onfalse = ir_function_create_block(func->ir_func, ast_function_label(func, "onfalse"));
 824         if (!onfalse)
 825             return false;
 826
 827         /* enter the block */
 828         func->curblock = onfalse;
 829
 830         /* generate */
 831         cgen = self->on_false->expression.codegen;
 832         if (!(*cgen)((ast_expression*)(self->on_false), func, false, &dummy))
 833             return false;
 834     } else
 835         onfalse = NULL;
 836
 837     /* Merge block were they all merge in to */
 838     merge = ir_function_create_block(func->ir_func, ast_function_label(func, "endif"));
 839     if (!merge)
 840         return false;
 841
 842     /* add jumps ot the merge block */
 843     if (ontrue && !ir_block_create_jump(ontrue, merge))
 844         return false;
 845     if (onfalse && !ir_block_create_jump(onfalse, merge))
 846         return false;
 847
 848     /* we create the if here, that way all blocks are ordered :)
 849      */
 850     if (!ir_block_create_if(cond, condval,
 851                             (ontrue  ? ontrue  : merge),
 852                             (onfalse ? onfalse : merge)))
 853     {
 854         return false;
 855     }
 856
 857     /* Now enter the merge block */
 858     func->curblock = merge;
 859
 860     return true;
 861 }
 862
 863 bool ast_ternary_codegen(ast_ternary *self, ast_function *func, bool lvalue, ir_value **out)
 864 {
 865     ast_expression_codegen *cgen;
 866
 867     ir_value *condval;
 868     ir_value *trueval, *falseval;
 869     ir_instr *phi;
 870
 871     ir_block *cond = func->curblock;
 872     ir_block *ontrue;
 873     ir_block *onfalse;
 874     ir_block *merge;
 875
 876     /* In theory it shouldn't be possible to pass through a node twice, but
 877      * in case we add any kind of optimization pass for the AST itself, it
 878      * may still happen, thus we remember a created ir_value and simply return one
 879      * if it already exists.
 880      */
 881     if (self->phi_out) {
 882         *out = self->phi_out;
 883         return true;
 884     }
 885
 886     /* Ternary can never create an lvalue... */
 887     if (lvalue)
 888         return false;
 889
 890     /* In the following, contraty to ast_ifthen, we assume both paths exist. */
 891
 892     /* generate the condition */
 893     func->curblock = cond;
 894     cgen = self->cond->expression.codegen;
 895     if (!(*cgen)((ast_expression*)(self->cond), func, false, &condval))
 896         return false;
 897
 898     /* create on-true block */
 899     ontrue = ir_function_create_block(func->ir_func, ast_function_label(func, "tern_T"));
 900     if (!ontrue)
 901         return false;
 902     else
 903     {
 904         /* enter the block */
 905         func->curblock = ontrue;
 906
 907         /* generate */
 908         cgen = self->on_true->expression.codegen;
 909         if (!(*cgen)((ast_expression*)(self->on_true), func, false, &trueval))
 910             return false;
 911     }
 912
 913     /* create on-false block */
 914     onfalse = ir_function_create_block(func->ir_func, ast_function_label(func, "tern_F"));
 915     if (!onfalse)
 916         return false;
 917     else
 918     {
 919         /* enter the block */
 920         func->curblock = onfalse;
 921
 922         /* generate */
 923         cgen = self->on_false->expression.codegen;
 924         if (!(*cgen)((ast_expression*)(self->on_false), func, false, &falseval))
 925             return false;
 926     }
 927
 928     /* create merge block */
 929     merge = ir_function_create_block(func->ir_func, ast_function_label(func, "tern_out"));
 930     if (!merge)
 931         return false;
 932     /* jump to merge block */
 933     if (!ir_block_create_jump(ontrue, merge))
 934         return false;
 935     if (!ir_block_create_jump(onfalse, merge))
 936         return false;
 937
 938     /* create if instruction */
 939     if (!ir_block_create_if(cond, condval, ontrue, onfalse))
 940         return false;
 941
 942     /* Now enter the merge block */
 943     func->curblock = merge;
 944
 945     /* Here, now, we need a PHI node
 946      * but first some sanity checking...
 947      */
 948     if (trueval->vtype != falseval->vtype) {
 949         /* error("ternary with different types on the two sides"); */
 950         return false;
 951     }
 952
 953     /* create PHI */
 954     phi = ir_block_create_phi(merge, ast_function_label(func, "phi"), trueval->vtype);
 955     if (!phi ||
 956         !ir_phi_add(phi, ontrue,  trueval) ||
 957         !ir_phi_add(phi, onfalse, falseval))
 958     {
 959         return false;
 960     }
 961
 962     self->phi_out = ir_phi_value(phi);
 963     *out = self->phi_out;
 964
 965     return true;
 966 }
 967
 968 bool ast_loop_codegen(ast_loop *self, ast_function *func, bool lvalue, ir_value **out)
 969 {
 970     ast_expression_codegen *cgen;
 971
 972     ir_value *dummy      = NULL;
 973     ir_value *precond    = NULL;
 974     ir_value *postcond   = NULL;
 975
 976     /* Since we insert some jumps "late" so we have blocks
 977      * ordered "nicely", we need to keep track of the actual end-blocks
 978      * of expressions to add the jumps to.
 979      */
 980     ir_block *bbody      = NULL, *end_bbody      = NULL;
 981     ir_block *bprecond   = NULL, *end_bprecond   = NULL;
 982     ir_block *bpostcond  = NULL, *end_bpostcond  = NULL;
 983     ir_block *bincrement = NULL, *end_bincrement = NULL;
 984     ir_block *bout       = NULL, *bin            = NULL;
 985
 986     /* let's at least move the outgoing block to the end */
 987     size_t    bout_id;
 988
 989     /* 'break' and 'continue' need to be able to find the right blocks */
 990     ir_block *bcontinue     = NULL;
 991     ir_block *bbreak        = NULL;
 992
 993     ir_block *old_bcontinue = NULL;
 994     ir_block *old_bbreak    = NULL;
 995
 996     ir_block *tmpblock      = NULL;
 997
 998     (void)lvalue;
 999     (void)out;
1000
1001     /* NOTE:
1002      * Should we ever need some kind of block ordering, better make this function
1003      * move blocks around than write a block ordering algorithm later... after all
1004      * the ast and ir should work together, not against each other.
1005      */
1006
1007     /* initexpr doesn't get its own block, it's pointless, it could create more blocks
1008      * anyway if for example it contains a ternary.
1009      */
1010     if (self->initexpr)
1011     {
1012         cgen = self->initexpr->expression.codegen;
1013         if (!(*cgen)((ast_expression*)(self->initexpr), func, false, &dummy))
1014             return false;
1015     }
1016
1017     /* Store the block from which we enter this chaos */
1018     bin = func->curblock;
1019
1020     /* The pre-loop condition needs its own block since we
1021      * need to be able to jump to the start of that expression.
1022      */
1023     if (self->precond)
1024     {
1025         bprecond = ir_function_create_block(func->ir_func, ast_function_label(func, "pre_loop_cond"));
1026         if (!bprecond)
1027             return false;
1028
1029         /* the pre-loop-condition the least important place to 'continue' at */
1030         bcontinue = bprecond;
1031
1032         /* enter */
1033         func->curblock = bprecond;
1034
1035         /* generate */
1036         cgen = self->precond->expression.codegen;
1037         if (!(*cgen)((ast_expression*)(self->precond), func, false, &precond))
1038             return false;
1039
1040         end_bprecond = func->curblock;
1041     } else {
1042         bprecond = end_bprecond = NULL;
1043     }
1044
1045     /* Now the next blocks won't be ordered nicely, but we need to
1046      * generate them this early for 'break' and 'continue'.
1047      */
1048     if (self->increment) {
1049         bincrement = ir_function_create_block(func->ir_func, ast_function_label(func, "loop_increment"));
1050         if (!bincrement)
1051             return false;
1052         bcontinue = bincrement; /* increment comes before the pre-loop-condition */
1053     } else {
1054         bincrement = end_bincrement = NULL;
1055     }
1056
1057     if (self->postcond) {
1058         bpostcond = ir_function_create_block(func->ir_func, ast_function_label(func, "post_loop_cond"));
1059         if (!bpostcond)
1060             return false;
1061         bcontinue = bpostcond; /* postcond comes before the increment */
1062     } else {
1063         bpostcond = end_bpostcond = NULL;
1064     }
1065
1066     bout_id = func->ir_func->blocks_count;
1067     bout = ir_function_create_block(func->ir_func, ast_function_label(func, "after_loop"));
1068     if (!bout)
1069         return false;
1070     bbreak = bout;
1071
1072     /* The loop body... */
1073     if (self->body)
1074     {
1075         bbody = ir_function_create_block(func->ir_func, ast_function_label(func, "loop_body"));
1076         if (!bbody)
1077             return false;
1078
1079         /* enter */
1080         func->curblock = bbody;
1081
1082         old_bbreak          = func->breakblock;
1083         old_bcontinue       = func->continueblock;
1084         func->breakblock    = bbreak;
1085         func->continueblock = bcontinue;
1086
1087         /* generate */
1088         cgen = self->body->expression.codegen;
1089         if (!(*cgen)((ast_expression*)(self->body), func, false, &dummy))
1090             return false;
1091
1092         end_bbody = func->curblock;
1093         func->breakblock    = old_bbreak;
1094         func->continueblock = old_bcontinue;
1095     }
1096
1097     /* post-loop-condition */
1098     if (self->postcond)
1099     {
1100         /* enter */
1101         func->curblock = bpostcond;
1102
1103         /* generate */
1104         cgen = self->postcond->expression.codegen;
1105         if (!(*cgen)((ast_expression*)(self->postcond), func, false, &postcond))
1106             return false;
1107
1108         end_bpostcond = func->curblock;
1109     }
1110
1111     /* The incrementor */
1112     if (self->increment)
1113     {
1114         /* enter */
1115         func->curblock = bincrement;
1116
1117         /* generate */
1118         cgen = self->increment->expression.codegen;
1119         if (!(*cgen)((ast_expression*)(self->increment), func, false, &dummy))
1120             return false;
1121
1122         end_bincrement = func->curblock;
1123     }
1124
1125     /* In any case now, we continue from the outgoing block */
1126     func->curblock = bout;
1127
1128     /* Now all blocks are in place */
1129     /* From 'bin' we jump to whatever comes first */
1130     if      (bprecond)   tmpblock = bprecond;
1131     else if (bbody)      tmpblock = bbody;
1132     else if (bpostcond)  tmpblock = bpostcond;
1133     else                 tmpblock = bout;
1134     if (!ir_block_create_jump(bin, tmpblock))
1135         return false;
1136
1137     /* From precond */
1138     if (bprecond)
1139     {
1140         ir_block *ontrue, *onfalse;
1141         if      (bbody)      ontrue = bbody;
1142         else if (bincrement) ontrue = bincrement;
1143         else if (bpostcond)  ontrue = bpostcond;
1144         else                 ontrue = bprecond;
1145         onfalse = bout;
1146         if (!ir_block_create_if(end_bprecond, precond, ontrue, onfalse))
1147             return false;
1148     }
1149
1150     /* from body */
1151     if (bbody)
1152     {
1153         if      (bincrement) tmpblock = bincrement;
1154         else if (bpostcond)  tmpblock = bpostcond;
1155         else if (bprecond)   tmpblock = bprecond;
1156         else                 tmpblock = bout;
1157         if (!ir_block_create_jump(end_bbody, tmpblock))
1158             return false;
1159     }
1160
1161     /* from increment */
1162     if (bincrement)
1163     {
1164         if      (bpostcond)  tmpblock = bpostcond;
1165         else if (bprecond)   tmpblock = bprecond;
1166         else if (bbody)      tmpblock = bbody;
1167         else                 tmpblock = bout;
1168         if (!ir_block_create_jump(end_bincrement, tmpblock))
1169             return false;
1170     }
1171
1172     /* from postcond */
1173     if (bpostcond)
1174     {
1175         ir_block *ontrue, *onfalse;
1176         if      (bprecond)   ontrue = bprecond;
1177         else if (bbody)      ontrue = bbody;
1178         else if (bincrement) ontrue = bincrement;
1179         else                 ontrue = bpostcond;
1180         onfalse = bout;
1181         if (!ir_block_create_if(end_bpostcond, postcond, ontrue, onfalse))
1182             return false;
1183     }
1184
1185     /* Move 'bout' to the end */
1186     if (!ir_function_blocks_remove(func->ir_func, bout_id) ||
1187         !ir_function_blocks_add(func->ir_func, bout))
1188     {
1189         ir_block_delete(bout);
1190         return false;
1191     }
1192
1193     return true;
1194 }
1195
1196 bool ast_call_codegen(ast_call *self, ast_function *func, bool lvalue, ir_value **out)
1197 {
1198     ast_expression_codegen *cgen;
1199     ir_value_vector         params;
1200     ir_instr               *callinstr;
1201     size_t i;
1202
1203     ir_value *funval = NULL;
1204
1205     /* return values are never rvalues */
1206     (void)lvalue;
1207
1208     cgen = self->func->expression.codegen;
1209     if (!(*cgen)((ast_expression*)(self->func), func, false, &funval))
1210         return false;
1211     if (!funval)
1212         return false;
1213
1214     MEM_VECTOR_INIT(&params, v);
1215
1216     /* parameters */
1217     for (i = 0; i < self->params_count; ++i)
1218     {
1219         ir_value *param;
1220         ast_expression *expr = self->params[i];
1221
1222         cgen = expr->expression.codegen;
1223         if (!(*cgen)(expr, func, false, &param))
1224             goto error;
1225         if (!param)
1226             goto error;
1227         if (!ir_value_vector_v_add(&params, param))
1228             goto error;
1229     }
1230
1231     callinstr = ir_block_create_call(func->curblock, ast_function_label(func, "call"), funval);
1232     if (!callinstr)
1233         goto error;
1234
1235     for (i = 0; i < params.v_count; ++i) {
1236         if (!ir_call_param(callinstr, params.v[i]))
1237             goto error;
1238     }
1239
1240     *out = ir_call_value(callinstr);
1241
1242     return true;
1243 error:
1244     MEM_VECTOR_CLEAR(&params, v);
1245     return false;
1246 }