]> git.xonotic.org Git - xonotic/gmqcc.git/blob - ast.c
Don't have the ast's codegen error on missing returns
[xonotic/gmqcc.git] / ast.c
1 /*
2  * Copyright (C) 2012
3  *     Wolfgang Bumiller
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining a copy of
6  * this software and associated documentation files (the "Software"), to deal in
7  * the Software without restriction, including without limitation the rights to
8  * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
9  * of the Software, and to permit persons to whom the Software is furnished to do
10  * so, subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice shall be included in all
13  * copies or substantial portions of the Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
21  * SOFTWARE.
22  */
23 #include <stdio.h>
24 #include <stdlib.h>
25 #include <string.h>
26
27 #include "gmqcc.h"
28 #include "ast.h"
29
30 #define ast_instantiate(T, ctx, destroyfn)                          \
31     T* self = (T*)mem_a(sizeof(T));                                 \
32     if (!self) {                                                    \
33         return NULL;                                                \
34     }                                                               \
35     ast_node_init((ast_node*)self, ctx, TYPE_##T);                  \
36     ( (ast_node*)self )->node.destroy = (ast_node_delete*)destroyfn
37
38 /* error handling */
39 static void asterror(lex_ctx ctx, const char *msg, ...)
40 {
41     va_list ap;
42     va_start(ap, msg);
43     cvprintmsg(ctx, LVL_ERROR, "error", msg, ap);
44     va_end(ap);
45 }
46
47 /* It must not be possible to get here. */
48 static GMQCC_NORETURN void _ast_node_destroy(ast_node *self)
49 {
50     fprintf(stderr, "ast node missing destroy()\n");
51     abort();
52 }
53
54 /* Initialize main ast node aprts */
55 static void ast_node_init(ast_node *self, lex_ctx ctx, int nodetype)
56 {
57     self->node.context = ctx;
58     self->node.destroy = &_ast_node_destroy;
59     self->node.keep    = false;
60     self->node.nodetype = nodetype;
61 }
62
63 /* General expression initialization */
64 static void ast_expression_init(ast_expression *self,
65                                 ast_expression_codegen *codegen)
66 {
67     self->expression.codegen = codegen;
68     self->expression.vtype   = TYPE_VOID;
69     self->expression.next    = NULL;
70     self->expression.outl    = NULL;
71     self->expression.outr    = NULL;
72     MEM_VECTOR_INIT(&self->expression, params);
73 }
74
75 static void ast_expression_delete(ast_expression *self)
76 {
77     size_t i;
78     if (self->expression.next)
79         ast_delete(self->expression.next);
80     for (i = 0; i < self->expression.params_count; ++i) {
81         ast_delete(self->expression.params[i]);
82     }
83     MEM_VECTOR_CLEAR(&self->expression, params);
84 }
85
86 static void ast_expression_delete_full(ast_expression *self)
87 {
88     ast_expression_delete(self);
89     mem_d(self);
90 }
91
92 MEM_VEC_FUNCTIONS(ast_expression_common, ast_value*, params)
93
94 ast_value* ast_value_copy(const ast_value *self)
95 {
96     size_t i;
97     const ast_expression_common *fromex;
98     ast_expression_common *selfex;
99     ast_value *cp = ast_value_new(self->expression.node.context, self->name, self->expression.vtype);
100     if (self->expression.next) {
101         cp->expression.next = ast_type_copy(self->expression.node.context, self->expression.next);
102         if (!cp->expression.next) {
103             ast_value_delete(cp);
104             return NULL;
105         }
106     }
107     fromex   = &self->expression;
108     selfex = &cp->expression;
109     for (i = 0; i < fromex->params_count; ++i) {
110         ast_value *v = ast_value_copy(fromex->params[i]);
111         if (!v || !ast_expression_common_params_add(selfex, v)) {
112             ast_value_delete(cp);
113             return NULL;
114         }
115     }
116     return cp;
117 }
118
119 bool ast_type_adopt_impl(ast_expression *self, const ast_expression *other)
120 {
121     size_t i;
122     const ast_expression_common *fromex;
123     ast_expression_common *selfex;
124     self->expression.vtype = other->expression.vtype;
125     if (other->expression.next) {
126         self->expression.next = (ast_expression*)ast_type_copy(ast_ctx(self), other->expression.next);
127         if (!self->expression.next)
128             return false;
129     }
130     fromex   = &other->expression;
131     selfex = &self->expression;
132     for (i = 0; i < fromex->params_count; ++i) {
133         ast_value *v = ast_value_copy(fromex->params[i]);
134         if (!v || !ast_expression_common_params_add(selfex, v))
135             return false;
136     }
137     return true;
138 }
139
140 static ast_expression* ast_shallow_type(lex_ctx ctx, int vtype)
141 {
142     ast_instantiate(ast_expression, ctx, ast_expression_delete_full);
143     ast_expression_init(self, NULL);
144     self->expression.codegen = NULL;
145     self->expression.next    = NULL;
146     self->expression.vtype   = vtype;
147     return self;
148 }
149
150 ast_expression* ast_type_copy(lex_ctx ctx, const ast_expression *ex)
151 {
152     size_t i;
153     const ast_expression_common *fromex;
154     ast_expression_common *selfex;
155
156     if (!ex)
157         return NULL;
158     else
159     {
160         ast_instantiate(ast_expression, ctx, ast_expression_delete_full);
161         ast_expression_init(self, NULL);
162
163         fromex   = &ex->expression;
164         selfex = &self->expression;
165
166         /* This may never be codegen()d */
167         selfex->codegen = NULL;
168
169         selfex->vtype = fromex->vtype;
170         if (fromex->next)
171         {
172             selfex->next = ast_type_copy(ctx, fromex->next);
173             if (!selfex->next) {
174                 ast_expression_delete_full(self);
175                 return NULL;
176             }
177         }
178         else
179             selfex->next = NULL;
180
181         for (i = 0; i < fromex->params_count; ++i) {
182             ast_value *v = ast_value_copy(fromex->params[i]);
183             if (!v || !ast_expression_common_params_add(selfex, v)) {
184                 ast_expression_delete_full(self);
185                 return NULL;
186             }
187         }
188
189         return self;
190     }
191 }
192
193 bool ast_compare_type(ast_expression *a, ast_expression *b)
194 {
195     if (a->expression.vtype != b->expression.vtype)
196         return false;
197     if (!a->expression.next != !b->expression.next)
198         return false;
199     if (a->expression.params_count != b->expression.params_count)
200         return false;
201     if (a->expression.params_count) {
202         size_t i;
203         for (i = 0; i < a->expression.params_count; ++i) {
204             if (!ast_compare_type((ast_expression*)a->expression.params[i],
205                                   (ast_expression*)b->expression.params[i]))
206                 return false;
207         }
208     }
209     if (a->expression.next)
210         return ast_compare_type(a->expression.next, b->expression.next);
211     return true;
212 }
213
214 ast_value* ast_value_new(lex_ctx ctx, const char *name, int t)
215 {
216     ast_instantiate(ast_value, ctx, ast_value_delete);
217     ast_expression_init((ast_expression*)self,
218                         (ast_expression_codegen*)&ast_value_codegen);
219     self->expression.node.keep = true; /* keep */
220
221     self->name = name ? util_strdup(name) : NULL;
222     self->expression.vtype = t;
223     self->expression.next  = NULL;
224     self->isconst = false;
225     memset(&self->constval, 0, sizeof(self->constval));
226
227     self->ir_v    = NULL;
228
229     return self;
230 }
231
232 void ast_value_delete(ast_value* self)
233 {
234     if (self->name)
235         mem_d((void*)self->name);
236     if (self->isconst) {
237         switch (self->expression.vtype)
238         {
239         case TYPE_STRING:
240             mem_d((void*)self->constval.vstring);
241             break;
242         case TYPE_FUNCTION:
243             /* unlink us from the function node */
244             self->constval.vfunc->vtype = NULL;
245             break;
246         /* NOTE: delete function? currently collected in
247          * the parser structure
248          */
249         default:
250             break;
251         }
252     }
253     ast_expression_delete((ast_expression*)self);
254     mem_d(self);
255 }
256
257 bool GMQCC_WARN ast_value_params_add(ast_value *self, ast_value *p)
258 {
259     return ast_expression_common_params_add(&self->expression, p);
260 }
261
262 bool ast_value_set_name(ast_value *self, const char *name)
263 {
264     if (self->name)
265         mem_d((void*)self->name);
266     self->name = util_strdup(name);
267     return !!self->name;
268 }
269
270 ast_binary* ast_binary_new(lex_ctx ctx, int op,
271                            ast_expression* left, ast_expression* right)
272 {
273     ast_instantiate(ast_binary, ctx, ast_binary_delete);
274     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_binary_codegen);
275
276     self->op = op;
277     self->left = left;
278     self->right = right;
279
280     if (op >= INSTR_EQ_F && op <= INSTR_GT)
281         self->expression.vtype = TYPE_FLOAT;
282     else if (op == INSTR_AND || op == INSTR_OR ||
283              op == INSTR_BITAND || op == INSTR_BITOR)
284         self->expression.vtype = TYPE_FLOAT;
285     else if (op == INSTR_MUL_VF || op == INSTR_MUL_FV)
286         self->expression.vtype = TYPE_VECTOR;
287     else if (op == INSTR_MUL_V)
288         self->expression.vtype = TYPE_FLOAT;
289     else
290         self->expression.vtype = left->expression.vtype;
291
292     return self;
293 }
294
295 void ast_binary_delete(ast_binary *self)
296 {
297     ast_unref(self->left);
298     ast_unref(self->right);
299     ast_expression_delete((ast_expression*)self);
300     mem_d(self);
301 }
302
303 ast_binstore* ast_binstore_new(lex_ctx ctx, int storop, int op,
304                                ast_expression* left, ast_expression* right)
305 {
306     ast_instantiate(ast_binstore, ctx, ast_binstore_delete);
307     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_binstore_codegen);
308
309     self->opstore = storop;
310     self->opbin   = op;
311     self->dest    = left;
312     self->source  = right;
313
314     self->expression.vtype = left->expression.vtype;
315     if (left->expression.next) {
316         self->expression.next = ast_type_copy(ctx, left);
317         if (!self->expression.next) {
318             ast_delete(self);
319             return NULL;
320         }
321     }
322     else
323         self->expression.next = NULL;
324
325     return self;
326 }
327
328 void ast_binstore_delete(ast_binstore *self)
329 {
330     ast_unref(self->dest);
331     ast_unref(self->source);
332     ast_expression_delete((ast_expression*)self);
333     mem_d(self);
334 }
335
336 ast_unary* ast_unary_new(lex_ctx ctx, int op,
337                          ast_expression *expr)
338 {
339     ast_instantiate(ast_unary, ctx, ast_unary_delete);
340     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_unary_codegen);
341
342     self->op = op;
343     self->operand = expr;
344
345     if (op >= INSTR_NOT_F && op <= INSTR_NOT_FNC) {
346         self->expression.vtype = TYPE_FLOAT;
347     } else
348         asterror(ctx, "cannot determine type of unary operation %s", asm_instr[op].m);
349
350     return self;
351 }
352
353 void ast_unary_delete(ast_unary *self)
354 {
355     ast_unref(self->operand);
356     ast_expression_delete((ast_expression*)self);
357     mem_d(self);
358 }
359
360 ast_return* ast_return_new(lex_ctx ctx, ast_expression *expr)
361 {
362     ast_instantiate(ast_return, ctx, ast_return_delete);
363     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_return_codegen);
364
365     self->operand = expr;
366
367     return self;
368 }
369
370 void ast_return_delete(ast_return *self)
371 {
372     if (self->operand)
373         ast_unref(self->operand);
374     ast_expression_delete((ast_expression*)self);
375     mem_d(self);
376 }
377
378 ast_entfield* ast_entfield_new(lex_ctx ctx, ast_expression *entity, ast_expression *field)
379 {
380     const ast_expression *outtype;
381
382     ast_instantiate(ast_entfield, ctx, ast_entfield_delete);
383
384     if (field->expression.vtype != TYPE_FIELD) {
385         mem_d(self);
386         return NULL;
387     }
388
389     outtype = field->expression.next;
390     if (!outtype) {
391         mem_d(self);
392         /* Error: field has no type... */
393         return NULL;
394     }
395
396     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_entfield_codegen);
397
398     self->entity = entity;
399     self->field  = field;
400
401     if (!ast_type_adopt(self, outtype)) {
402         ast_entfield_delete(self);
403         return NULL;
404     }
405
406     return self;
407 }
408
409 void ast_entfield_delete(ast_entfield *self)
410 {
411     ast_unref(self->entity);
412     ast_unref(self->field);
413     ast_expression_delete((ast_expression*)self);
414     mem_d(self);
415 }
416
417 ast_member* ast_member_new(lex_ctx ctx, ast_expression *owner, unsigned int field)
418 {
419     ast_instantiate(ast_member, ctx, ast_member_delete);
420     if (field >= 3) {
421         mem_d(self);
422         return NULL;
423     }
424
425     if (owner->expression.vtype != TYPE_VECTOR &&
426         owner->expression.vtype != TYPE_FIELD) {
427         asterror(ctx, "member-access on an invalid owner of type %s\n", type_name[owner->expression.vtype]);
428         mem_d(self);
429         return NULL;
430     }
431
432     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_member_codegen);
433     self->expression.node.keep = true; /* keep */
434
435     if (owner->expression.vtype == TYPE_VECTOR) {
436         self->expression.vtype = TYPE_FLOAT;
437         self->expression.next  = NULL;
438     } else {
439         self->expression.vtype = TYPE_FIELD;
440         self->expression.next = ast_shallow_type(ctx, TYPE_FLOAT);
441     }
442
443     self->owner = owner;
444     self->field = field;
445
446     return self;
447 }
448
449 void ast_member_delete(ast_member *self)
450 {
451     /* The owner is always an ast_value, which has .keep=true,
452      * also: ast_members are usually deleted after the owner, thus
453      * this will cause invalid access
454     ast_unref(self->owner);
455      * once we allow (expression).x to access a vector-member, we need
456      * to change this: preferably by creating an alternate ast node for this
457      * purpose that is not garbage-collected.
458     */
459     ast_expression_delete((ast_expression*)self);
460     mem_d(self);
461 }
462
463 ast_ifthen* ast_ifthen_new(lex_ctx ctx, ast_expression *cond, ast_expression *ontrue, ast_expression *onfalse)
464 {
465     ast_instantiate(ast_ifthen, ctx, ast_ifthen_delete);
466     if (!ontrue && !onfalse) {
467         /* because it is invalid */
468         mem_d(self);
469         return NULL;
470     }
471     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_ifthen_codegen);
472
473     self->cond     = cond;
474     self->on_true  = ontrue;
475     self->on_false = onfalse;
476
477     return self;
478 }
479
480 void ast_ifthen_delete(ast_ifthen *self)
481 {
482     ast_unref(self->cond);
483     if (self->on_true)
484         ast_unref(self->on_true);
485     if (self->on_false)
486         ast_unref(self->on_false);
487     ast_expression_delete((ast_expression*)self);
488     mem_d(self);
489 }
490
491 ast_ternary* ast_ternary_new(lex_ctx ctx, ast_expression *cond, ast_expression *ontrue, ast_expression *onfalse)
492 {
493     ast_instantiate(ast_ternary, ctx, ast_ternary_delete);
494     /* This time NEITHER must be NULL */
495     if (!ontrue || !onfalse) {
496         mem_d(self);
497         return NULL;
498     }
499     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_ternary_codegen);
500
501     self->cond     = cond;
502     self->on_true  = ontrue;
503     self->on_false = onfalse;
504     self->phi_out  = NULL;
505
506     return self;
507 }
508
509 void ast_ternary_delete(ast_ternary *self)
510 {
511     ast_unref(self->cond);
512     ast_unref(self->on_true);
513     ast_unref(self->on_false);
514     ast_expression_delete((ast_expression*)self);
515     mem_d(self);
516 }
517
518 ast_loop* ast_loop_new(lex_ctx ctx,
519                        ast_expression *initexpr,
520                        ast_expression *precond,
521                        ast_expression *postcond,
522                        ast_expression *increment,
523                        ast_expression *body)
524 {
525     ast_instantiate(ast_loop, ctx, ast_loop_delete);
526     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_loop_codegen);
527
528     self->initexpr  = initexpr;
529     self->precond   = precond;
530     self->postcond  = postcond;
531     self->increment = increment;
532     self->body      = body;
533
534     return self;
535 }
536
537 void ast_loop_delete(ast_loop *self)
538 {
539     if (self->initexpr)
540         ast_unref(self->initexpr);
541     if (self->precond)
542         ast_unref(self->precond);
543     if (self->postcond)
544         ast_unref(self->postcond);
545     if (self->increment)
546         ast_unref(self->increment);
547     if (self->body)
548         ast_unref(self->body);
549     ast_expression_delete((ast_expression*)self);
550     mem_d(self);
551 }
552
553 ast_call* ast_call_new(lex_ctx ctx,
554                        ast_expression *funcexpr)
555 {
556     ast_instantiate(ast_call, ctx, ast_call_delete);
557     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_call_codegen);
558
559     MEM_VECTOR_INIT(self, params);
560
561     self->func = funcexpr;
562
563     self->expression.vtype = funcexpr->expression.next->expression.vtype;
564     if (funcexpr->expression.next->expression.next)
565         self->expression.next = ast_type_copy(ctx, funcexpr->expression.next->expression.next);
566
567     return self;
568 }
569 MEM_VEC_FUNCTIONS(ast_call, ast_expression*, params)
570
571 void ast_call_delete(ast_call *self)
572 {
573     size_t i;
574     for (i = 0; i < self->params_count; ++i)
575         ast_unref(self->params[i]);
576     MEM_VECTOR_CLEAR(self, params);
577
578     if (self->func)
579         ast_unref(self->func);
580
581     ast_expression_delete((ast_expression*)self);
582     mem_d(self);
583 }
584
585 ast_store* ast_store_new(lex_ctx ctx, int op,
586                          ast_expression *dest, ast_expression *source)
587 {
588     ast_instantiate(ast_store, ctx, ast_store_delete);
589     ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_store_codegen);
590
591     self->op = op;
592     self->dest = dest;
593     self->source = source;
594
595     return self;
596 }
597
598 void ast_store_delete(ast_store *self)
599 {
600     ast_unref(self->dest);
601     ast_unref(self->source);
602     ast_expression_delete((ast_expression*)self);
603     mem_d(self);
604 }
605
606 ast_block* ast_block_new(lex_ctx ctx)
607 {
608     ast_instantiate(ast_block, ctx, ast_block_delete);
609     ast_expression_init((ast_expression*)self,
610                         (ast_expression_codegen*)&ast_block_codegen);
611
612     MEM_VECTOR_INIT(self, locals);
613     MEM_VECTOR_INIT(self, exprs);
614     MEM_VECTOR_INIT(self, collect);
615
616     return self;
617 }
618 MEM_VEC_FUNCTIONS(ast_block, ast_value*, locals)
619 MEM_VEC_FUNCTIONS(ast_block, ast_expression*, exprs)
620 MEM_VEC_FUNCTIONS(ast_block, ast_expression*, collect)
621
622 bool ast_block_collect(ast_block *self, ast_expression *expr)
623 {
624     if (!ast_block_collect_add(self, expr))
625         return false;
626     expr->expression.node.keep = true;
627     return true;
628 }
629
630 void ast_block_delete(ast_block *self)
631 {
632     size_t i;
633     for (i = 0; i < self->exprs_count; ++i)
634         ast_unref(self->exprs[i]);
635     MEM_VECTOR_CLEAR(self, exprs);
636     for (i = 0; i < self->locals_count; ++i)
637         ast_delete(self->locals[i]);
638     MEM_VECTOR_CLEAR(self, locals);
639     for (i = 0; i < self->collect_count; ++i)
640         ast_delete(self->collect[i]);
641     MEM_VECTOR_CLEAR(self, collect);
642     ast_expression_delete((ast_expression*)self);
643     mem_d(self);
644 }
645
646 bool ast_block_set_type(ast_block *self, ast_expression *from)
647 {
648     if (self->expression.next)
649         ast_delete(self->expression.next);
650     self->expression.vtype = from->expression.vtype;
651     if (from->expression.next) {
652         self->expression.next = ast_type_copy(self->expression.node.context, from->expression.next);
653         if (!self->expression.next)
654             return false;
655     }
656     else
657         self->expression.next = NULL;
658     return true;
659 }
660
661 ast_function* ast_function_new(lex_ctx ctx, const char *name, ast_value *vtype)
662 {
663     ast_instantiate(ast_function, ctx, ast_function_delete);
664
665     if (!vtype ||
666         vtype->isconst ||
667         vtype->expression.vtype != TYPE_FUNCTION)
668     {
669         mem_d(self);
670         return NULL;
671     }
672
673     self->vtype = vtype;
674     self->name = name ? util_strdup(name) : NULL;
675     MEM_VECTOR_INIT(self, blocks);
676
677     self->labelcount = 0;
678     self->builtin = 0;
679
680     self->ir_func = NULL;
681     self->curblock = NULL;
682
683     self->breakblock    = NULL;
684     self->continueblock = NULL;
685
686     vtype->isconst = true;
687     vtype->constval.vfunc = self;
688
689     return self;
690 }
691
692 MEM_VEC_FUNCTIONS(ast_function, ast_block*, blocks)
693
694 void ast_function_delete(ast_function *self)
695 {
696     size_t i;
697     if (self->name)
698         mem_d((void*)self->name);
699     if (self->vtype) {
700         /* ast_value_delete(self->vtype); */
701         self->vtype->isconst = false;
702         self->vtype->constval.vfunc = NULL;
703         /* We use unref - if it was stored in a global table it is supposed
704          * to be deleted from *there*
705          */
706         ast_unref(self->vtype);
707     }
708     for (i = 0; i < self->blocks_count; ++i)
709         ast_delete(self->blocks[i]);
710     MEM_VECTOR_CLEAR(self, blocks);
711     mem_d(self);
712 }
713
714 static void ast_util_hexitoa(char *buf, size_t size, unsigned int num)
715 {
716     unsigned int base = 10;
717 #define checknul() do { if (size == 1) { *buf = 0; return; } } while (0)
718 #define addch(x) do { *buf++ = (x); --size; checknul(); } while (0)
719     if (size < 1)
720         return;
721     checknul();
722     if (!num)
723         addch('0');
724     else {
725         while (num)
726         {
727             int digit = num % base;
728             num /= base;
729             addch('0' + digit);
730         }
731     }
732
733     *buf = 0;
734 #undef addch
735 #undef checknul
736 }
737
738 const char* ast_function_label(ast_function *self, const char *prefix)
739 {
740     size_t id = (self->labelcount++);
741     size_t len = strlen(prefix);
742     strncpy(self->labelbuf, prefix, sizeof(self->labelbuf));
743     ast_util_hexitoa(self->labelbuf + len, sizeof(self->labelbuf)-len, id);
744     return self->labelbuf;
745 }
746
747 /*********************************************************************/
748 /* AST codegen part
749  * by convention you must never pass NULL to the 'ir_value **out'
750  * parameter. If you really don't care about the output, pass a dummy.
751  * But I can't imagine a pituation where the output is truly unnecessary.
752  */
753
754 bool ast_value_codegen(ast_value *self, ast_function *func, bool lvalue, ir_value **out)
755 {
756     /* NOTE: This is the codegen for a variable used in an expression.
757      * It is not the codegen to generate the value. For this purpose,
758      * ast_local_codegen and ast_global_codegen are to be used before this
759      * is executed. ast_function_codegen should take care of its locals,
760      * and the ast-user should take care of ast_global_codegen to be used
761      * on all the globals.
762      */
763     if (!self->ir_v) {
764         asterror(ast_ctx(self), "ast_value used before generated (%s)\n", self->name);
765         return false;
766     }
767     *out = self->ir_v;
768     return true;
769 }
770
771 bool ast_global_codegen(ast_value *self, ir_builder *ir)
772 {
773     ir_value *v = NULL;
774     if (self->isconst && self->expression.vtype == TYPE_FUNCTION)
775     {
776         ir_function *func = ir_builder_create_function(ir, self->name, self->expression.next->expression.vtype);
777         if (!func)
778             return false;
779         func->context = ast_ctx(self);
780
781         self->constval.vfunc->ir_func = func;
782         self->ir_v = func->value;
783         /* The function is filled later on ast_function_codegen... */
784         return true;
785     }
786
787     if (self->expression.vtype == TYPE_FIELD) {
788         v = ir_builder_create_field(ir, self->name, self->expression.next->expression.vtype);
789         if (!v)
790             return false;
791         if (self->isconst) {
792             asterror(ast_ctx(self), "TODO: constant field pointers with value\n");
793             goto error;
794         }
795         self->ir_v = v;
796         return true;
797     }
798
799     v = ir_builder_create_global(ir, self->name, self->expression.vtype);
800     if (!v) {
801         asterror(ast_ctx(self), "ir_builder_create_global failed\n");
802         return false;
803     }
804
805     if (self->isconst) {
806         switch (self->expression.vtype)
807         {
808             case TYPE_FLOAT:
809                 if (!ir_value_set_float(v, self->constval.vfloat))
810                     goto error;
811                 break;
812             case TYPE_VECTOR:
813                 if (!ir_value_set_vector(v, self->constval.vvec))
814                     goto error;
815                 break;
816             case TYPE_STRING:
817                 if (!ir_value_set_string(v, self->constval.vstring))
818                     goto error;
819                 break;
820             case TYPE_FUNCTION:
821                 asterror(ast_ctx(self), "global of type function not properly generated\n");
822                 goto error;
823                 /* Cannot generate an IR value for a function,
824                  * need a pointer pointing to a function rather.
825                  */
826             default:
827                 asterror(ast_ctx(self), "TODO: global constant type %i\n", self->expression.vtype);
828                 break;
829         }
830     }
831
832     /* link us to the ir_value */
833     self->ir_v = v;
834     return true;
835
836 error: /* clean up */
837     ir_value_delete(v);
838     return false;
839 }
840
841 bool ast_local_codegen(ast_value *self, ir_function *func, bool param)
842 {
843     ir_value *v = NULL;
844     if (self->isconst && self->expression.vtype == TYPE_FUNCTION)
845     {
846         /* Do we allow local functions? I think not...
847          * this is NOT a function pointer atm.
848          */
849         return false;
850     }
851
852     v = ir_function_create_local(func, self->name, self->expression.vtype, param);
853     if (!v)
854         return false;
855
856     /* A constant local... hmmm...
857      * I suppose the IR will have to deal with this
858      */
859     if (self->isconst) {
860         switch (self->expression.vtype)
861         {
862             case TYPE_FLOAT:
863                 if (!ir_value_set_float(v, self->constval.vfloat))
864                     goto error;
865                 break;
866             case TYPE_VECTOR:
867                 if (!ir_value_set_vector(v, self->constval.vvec))
868                     goto error;
869                 break;
870             case TYPE_STRING:
871                 if (!ir_value_set_string(v, self->constval.vstring))
872                     goto error;
873                 break;
874             default:
875                 asterror(ast_ctx(self), "TODO: global constant type %i\n", self->expression.vtype);
876                 break;
877         }
878     }
879
880     /* link us to the ir_value */
881     self->ir_v = v;
882     return true;
883
884 error: /* clean up */
885     ir_value_delete(v);
886     return false;
887 }
888
889 bool ast_function_codegen(ast_function *self, ir_builder *ir)
890 {
891     ir_function *irf;
892     ir_value    *dummy;
893     ast_expression_common *ec;
894     size_t    i;
895
896     irf = self->ir_func;
897     if (!irf) {
898         asterror(ast_ctx(self), "ast_function's related ast_value was not generated yet\n");
899         return false;
900     }
901
902     /* fill the parameter list */
903     ec = &self->vtype->expression;
904     for (i = 0; i < ec->params_count; ++i)
905     {
906         if (!ir_function_params_add(irf, ec->params[i]->expression.vtype))
907             return false;
908         if (!self->builtin) {
909             if (!ast_local_codegen(ec->params[i], self->ir_func, true))
910                 return false;
911         }
912     }
913
914     if (self->builtin) {
915         irf->builtin = self->builtin;
916         return true;
917     }
918
919     if (!self->blocks_count) {
920         asterror(ast_ctx(self), "function `%s` has no body", self->name);
921         return false;
922     }
923
924     self->curblock = ir_function_create_block(irf, "entry");
925     if (!self->curblock)
926         return false;
927
928     for (i = 0; i < self->blocks_count; ++i) {
929         ast_expression_codegen *gen = self->blocks[i]->expression.codegen;
930         if (!(*gen)((ast_expression*)self->blocks[i], self, false, &dummy))
931             return false;
932     }
933
934     /* TODO: check return types */
935     if (!self->curblock->is_return)
936     {
937         return ir_block_create_return(self->curblock, NULL);
938         /* From now on the parser has to handle this situation */
939 #if 0
940         if (!self->vtype->expression.next ||
941             self->vtype->expression.next->expression.vtype == TYPE_VOID)
942         {
943             return ir_block_create_return(self->curblock, NULL);
944         }
945         else
946         {
947             /* error("missing return"); */
948             asterror(ast_ctx(self), "function `%s` missing return value", self->name);
949             return false;
950         }
951 #endif
952     }
953     return true;
954 }
955
956 /* Note, you will not see ast_block_codegen generate ir_blocks.
957  * To the AST and the IR, blocks are 2 different things.
958  * In the AST it represents a block of code, usually enclosed in
959  * curly braces {...}.
960  * While in the IR it represents a block in terms of control-flow.
961  */
962 bool ast_block_codegen(ast_block *self, ast_function *func, bool lvalue, ir_value **out)
963 {
964     size_t i;
965
966     /* We don't use this
967      * Note: an ast-representation using the comma-operator
968      * of the form: (a, b, c) = x should not assign to c...
969      */
970     (void)lvalue;
971     if (self->expression.outr) {
972         *out = self->expression.outr;
973         return true;
974     }
975
976     /* output is NULL at first, we'll have each expression
977      * assign to out output, thus, a comma-operator represention
978      * using an ast_block will return the last generated value,
979      * so: (b, c) + a  executed both b and c, and returns c,
980      * which is then added to a.
981      */
982     *out = NULL;
983
984     /* generate locals */
985     for (i = 0; i < self->locals_count; ++i)
986     {
987         if (!ast_local_codegen(self->locals[i], func->ir_func, false))
988             return false;
989     }
990
991     for (i = 0; i < self->exprs_count; ++i)
992     {
993         ast_expression_codegen *gen = self->exprs[i]->expression.codegen;
994         if (!(*gen)(self->exprs[i], func, false, out))
995             return false;
996     }
997
998     self->expression.outr = *out;
999
1000     return true;
1001 }
1002
1003 bool ast_store_codegen(ast_store *self, ast_function *func, bool lvalue, ir_value **out)
1004 {
1005     ast_expression_codegen *cgen;
1006     ir_value *left, *right;
1007
1008     if (lvalue && self->expression.outl) {
1009         *out = self->expression.outl;
1010         return true;
1011     }
1012
1013     if (!lvalue && self->expression.outr) {
1014         *out = self->expression.outr;
1015         return true;
1016     }
1017
1018     cgen = self->dest->expression.codegen;
1019     /* lvalue! */
1020     if (!(*cgen)((ast_expression*)(self->dest), func, true, &left))
1021         return false;
1022     self->expression.outl = left;
1023
1024     cgen = self->source->expression.codegen;
1025     /* rvalue! */
1026     if (!(*cgen)((ast_expression*)(self->source), func, false, &right))
1027         return false;
1028
1029     if (!ir_block_create_store_op(func->curblock, self->op, left, right))
1030         return false;
1031     self->expression.outr = right;
1032
1033     /* Theoretically, an assinment returns its left side as an
1034      * lvalue, if we don't need an lvalue though, we return
1035      * the right side as an rvalue, otherwise we have to
1036      * somehow know whether or not we need to dereference the pointer
1037      * on the left side - that is: OP_LOAD if it was an address.
1038      * Also: in original QC we cannot OP_LOADP *anyway*.
1039      */
1040     *out = (lvalue ? left : right);
1041
1042     return true;
1043 }
1044
1045 bool ast_binary_codegen(ast_binary *self, ast_function *func, bool lvalue, ir_value **out)
1046 {
1047     ast_expression_codegen *cgen;
1048     ir_value *left, *right;
1049
1050     /* In the context of a binary operation, we can disregard
1051      * the lvalue flag.
1052      */
1053     (void)lvalue;
1054     if (self->expression.outr) {
1055         *out = self->expression.outr;
1056         return true;
1057     }
1058
1059     cgen = self->left->expression.codegen;
1060     /* lvalue! */
1061     if (!(*cgen)((ast_expression*)(self->left), func, false, &left))
1062         return false;
1063
1064     cgen = self->right->expression.codegen;
1065     /* rvalue! */
1066     if (!(*cgen)((ast_expression*)(self->right), func, false, &right))
1067         return false;
1068
1069     *out = ir_block_create_binop(func->curblock, ast_function_label(func, "bin"),
1070                                  self->op, left, right);
1071     if (!*out)
1072         return false;
1073     self->expression.outr = *out;
1074
1075     return true;
1076 }
1077
1078 bool ast_binstore_codegen(ast_binstore *self, ast_function *func, bool lvalue, ir_value **out)
1079 {
1080     ast_expression_codegen *cgen;
1081     ir_value *leftl, *leftr, *right, *bin;
1082
1083     if (lvalue && self->expression.outl) {
1084         *out = self->expression.outl;
1085         return true;
1086     }
1087
1088     if (!lvalue && self->expression.outr) {
1089         *out = self->expression.outr;
1090         return true;
1091     }
1092
1093     /* for a binstore we need both an lvalue and an rvalue for the left side */
1094     /* rvalue of destination! */
1095     cgen = self->dest->expression.codegen;
1096     if (!(*cgen)((ast_expression*)(self->dest), func, false, &leftr))
1097         return false;
1098
1099     /* source as rvalue only */
1100     cgen = self->source->expression.codegen;
1101     if (!(*cgen)((ast_expression*)(self->source), func, false, &right))
1102         return false;
1103
1104     /* now the binary */
1105     bin = ir_block_create_binop(func->curblock, ast_function_label(func, "binst"),
1106                                 self->opbin, leftr, right);
1107     self->expression.outr = bin;
1108
1109     /* now store them */
1110     cgen = self->dest->expression.codegen;
1111     /* lvalue of destination */
1112     if (!(*cgen)((ast_expression*)(self->dest), func, true, &leftl))
1113         return false;
1114     self->expression.outl = leftl;
1115
1116     if (!ir_block_create_store_op(func->curblock, self->opstore, leftl, bin))
1117         return false;
1118     self->expression.outr = bin;
1119
1120     /* Theoretically, an assinment returns its left side as an
1121      * lvalue, if we don't need an lvalue though, we return
1122      * the right side as an rvalue, otherwise we have to
1123      * somehow know whether or not we need to dereference the pointer
1124      * on the left side - that is: OP_LOAD if it was an address.
1125      * Also: in original QC we cannot OP_LOADP *anyway*.
1126      */
1127     *out = (lvalue ? leftl : bin);
1128
1129     return true;
1130 }
1131
1132 bool ast_unary_codegen(ast_unary *self, ast_function *func, bool lvalue, ir_value **out)
1133 {
1134     ast_expression_codegen *cgen;
1135     ir_value *operand;
1136
1137     /* In the context of a unary operation, we can disregard
1138      * the lvalue flag.
1139      */
1140     (void)lvalue;
1141     if (self->expression.outr) {
1142         *out = self->expression.outr;
1143         return true;
1144     }
1145
1146     cgen = self->operand->expression.codegen;
1147     /* lvalue! */
1148     if (!(*cgen)((ast_expression*)(self->operand), func, false, &operand))
1149         return false;
1150
1151     *out = ir_block_create_unary(func->curblock, ast_function_label(func, "unary"),
1152                                  self->op, operand);
1153     if (!*out)
1154         return false;
1155     self->expression.outr = *out;
1156
1157     return true;
1158 }
1159
1160 bool ast_return_codegen(ast_return *self, ast_function *func, bool lvalue, ir_value **out)
1161 {
1162     ast_expression_codegen *cgen;
1163     ir_value *operand;
1164
1165     /* In the context of a return operation, we can disregard
1166      * the lvalue flag.
1167      */
1168     (void)lvalue;
1169     if (self->expression.outr) {
1170         asterror(ast_ctx(self), "internal error: ast_return cannot be reused, it bears no result!\n");
1171         return false;
1172     }
1173     self->expression.outr = (ir_value*)1;
1174
1175     if (self->operand) {
1176         cgen = self->operand->expression.codegen;
1177         /* lvalue! */
1178         if (!(*cgen)((ast_expression*)(self->operand), func, false, &operand))
1179             return false;
1180
1181         if (!ir_block_create_return(func->curblock, operand))
1182             return false;
1183     } else {
1184         if (!ir_block_create_return(func->curblock, NULL))
1185             return false;
1186     }
1187
1188     return true;
1189 }
1190
1191 bool ast_entfield_codegen(ast_entfield *self, ast_function *func, bool lvalue, ir_value **out)
1192 {
1193     ast_expression_codegen *cgen;
1194     ir_value *ent, *field;
1195
1196     /* This function needs to take the 'lvalue' flag into account!
1197      * As lvalue we provide a field-pointer, as rvalue we provide the
1198      * value in a temp.
1199      */
1200
1201     if (lvalue && self->expression.outl) {
1202         *out = self->expression.outl;
1203         return true;
1204     }
1205
1206     if (!lvalue && self->expression.outr) {
1207         *out = self->expression.outr;
1208         return true;
1209     }
1210
1211     cgen = self->entity->expression.codegen;
1212     if (!(*cgen)((ast_expression*)(self->entity), func, false, &ent))
1213         return false;
1214
1215     cgen = self->field->expression.codegen;
1216     if (!(*cgen)((ast_expression*)(self->field), func, false, &field))
1217         return false;
1218
1219     if (lvalue) {
1220         /* address! */
1221         *out = ir_block_create_fieldaddress(func->curblock, ast_function_label(func, "efa"),
1222                                             ent, field);
1223     } else {
1224         *out = ir_block_create_load_from_ent(func->curblock, ast_function_label(func, "efv"),
1225                                              ent, field, self->expression.vtype);
1226     }
1227     if (!*out) {
1228         asterror(ast_ctx(self), "failed to create %s instruction (output type %s)",
1229                  (lvalue ? "ADDRESS" : "FIELD"),
1230                  type_name[self->expression.vtype]);
1231         return false;
1232     }
1233
1234     if (lvalue)
1235         self->expression.outl = *out;
1236     else
1237         self->expression.outr = *out;
1238
1239     /* Hm that should be it... */
1240     return true;
1241 }
1242
1243 bool ast_member_codegen(ast_member *self, ast_function *func, bool lvalue, ir_value **out)
1244 {
1245     ast_expression_codegen *cgen;
1246     ir_value *vec;
1247
1248     /* in QC this is always an lvalue */
1249     (void)lvalue;
1250     if (self->expression.outl) {
1251         *out = self->expression.outl;
1252         return true;
1253     }
1254
1255     cgen = self->owner->expression.codegen;
1256     if (!(*cgen)((ast_expression*)(self->owner), func, true, &vec))
1257         return false;
1258
1259     if (vec->vtype != TYPE_VECTOR &&
1260         !(vec->vtype == TYPE_FIELD && self->owner->expression.next->expression.vtype == TYPE_VECTOR))
1261     {
1262         return false;
1263     }
1264
1265     *out = ir_value_vector_member(vec, self->field);
1266     self->expression.outl = *out;
1267
1268     return (*out != NULL);
1269 }
1270
1271 bool ast_ifthen_codegen(ast_ifthen *self, ast_function *func, bool lvalue, ir_value **out)
1272 {
1273     ast_expression_codegen *cgen;
1274
1275     ir_value *condval;
1276     ir_value *dummy;
1277
1278     ir_block *cond = func->curblock;
1279     ir_block *ontrue;
1280     ir_block *onfalse;
1281     ir_block *merge;
1282
1283     /* We don't output any value, thus also don't care about r/lvalue */
1284     (void)out;
1285     (void)lvalue;
1286
1287     if (self->expression.outr) {
1288         asterror(ast_ctx(self), "internal error: ast_ifthen cannot be reused, it bears no result!\n");
1289         return false;
1290     }
1291     self->expression.outr = (ir_value*)1;
1292
1293     /* generate the condition */
1294     func->curblock = cond;
1295     cgen = self->cond->expression.codegen;
1296     if (!(*cgen)((ast_expression*)(self->cond), func, false, &condval))
1297         return false;
1298
1299     /* on-true path */
1300
1301     if (self->on_true) {
1302         /* create on-true block */
1303         ontrue = ir_function_create_block(func->ir_func, ast_function_label(func, "ontrue"));
1304         if (!ontrue)
1305             return false;
1306
1307         /* enter the block */
1308         func->curblock = ontrue;
1309
1310         /* generate */
1311         cgen = self->on_true->expression.codegen;
1312         if (!(*cgen)((ast_expression*)(self->on_true), func, false, &dummy))
1313             return false;
1314     } else
1315         ontrue = NULL;
1316
1317     /* on-false path */
1318     if (self->on_false) {
1319         /* create on-false block */
1320         onfalse = ir_function_create_block(func->ir_func, ast_function_label(func, "onfalse"));
1321         if (!onfalse)
1322             return false;
1323
1324         /* enter the block */
1325         func->curblock = onfalse;
1326
1327         /* generate */
1328         cgen = self->on_false->expression.codegen;
1329         if (!(*cgen)((ast_expression*)(self->on_false), func, false, &dummy))
1330             return false;
1331     } else
1332         onfalse = NULL;
1333
1334     /* Merge block were they all merge in to */
1335     merge = ir_function_create_block(func->ir_func, ast_function_label(func, "endif"));
1336     if (!merge)
1337         return false;
1338
1339     /* add jumps ot the merge block */
1340     if (ontrue && !ontrue->final && !ir_block_create_jump(ontrue, merge))
1341         return false;
1342     if (onfalse && !onfalse->final && !ir_block_create_jump(onfalse, merge))
1343         return false;
1344
1345     /* we create the if here, that way all blocks are ordered :)
1346      */
1347     if (!ir_block_create_if(cond, condval,
1348                             (ontrue  ? ontrue  : merge),
1349                             (onfalse ? onfalse : merge)))
1350     {
1351         return false;
1352     }
1353
1354     /* Now enter the merge block */
1355     func->curblock = merge;
1356
1357     return true;
1358 }
1359
1360 bool ast_ternary_codegen(ast_ternary *self, ast_function *func, bool lvalue, ir_value **out)
1361 {
1362     ast_expression_codegen *cgen;
1363
1364     ir_value *condval;
1365     ir_value *trueval, *falseval;
1366     ir_instr *phi;
1367
1368     ir_block *cond = func->curblock;
1369     ir_block *ontrue;
1370     ir_block *onfalse;
1371     ir_block *merge;
1372
1373     /* Ternary can never create an lvalue... */
1374     if (lvalue)
1375         return false;
1376
1377     /* In theory it shouldn't be possible to pass through a node twice, but
1378      * in case we add any kind of optimization pass for the AST itself, it
1379      * may still happen, thus we remember a created ir_value and simply return one
1380      * if it already exists.
1381      */
1382     if (self->phi_out) {
1383         *out = self->phi_out;
1384         return true;
1385     }
1386
1387     /* In the following, contraty to ast_ifthen, we assume both paths exist. */
1388
1389     /* generate the condition */
1390     func->curblock = cond;
1391     cgen = self->cond->expression.codegen;
1392     if (!(*cgen)((ast_expression*)(self->cond), func, false, &condval))
1393         return false;
1394
1395     /* create on-true block */
1396     ontrue = ir_function_create_block(func->ir_func, ast_function_label(func, "tern_T"));
1397     if (!ontrue)
1398         return false;
1399     else
1400     {
1401         /* enter the block */
1402         func->curblock = ontrue;
1403
1404         /* generate */
1405         cgen = self->on_true->expression.codegen;
1406         if (!(*cgen)((ast_expression*)(self->on_true), func, false, &trueval))
1407             return false;
1408     }
1409
1410     /* create on-false block */
1411     onfalse = ir_function_create_block(func->ir_func, ast_function_label(func, "tern_F"));
1412     if (!onfalse)
1413         return false;
1414     else
1415     {
1416         /* enter the block */
1417         func->curblock = onfalse;
1418
1419         /* generate */
1420         cgen = self->on_false->expression.codegen;
1421         if (!(*cgen)((ast_expression*)(self->on_false), func, false, &falseval))
1422             return false;
1423     }
1424
1425     /* create merge block */
1426     merge = ir_function_create_block(func->ir_func, ast_function_label(func, "tern_out"));
1427     if (!merge)
1428         return false;
1429     /* jump to merge block */
1430     if (!ir_block_create_jump(ontrue, merge))
1431         return false;
1432     if (!ir_block_create_jump(onfalse, merge))
1433         return false;
1434
1435     /* create if instruction */
1436     if (!ir_block_create_if(cond, condval, ontrue, onfalse))
1437         return false;
1438
1439     /* Now enter the merge block */
1440     func->curblock = merge;
1441
1442     /* Here, now, we need a PHI node
1443      * but first some sanity checking...
1444      */
1445     if (trueval->vtype != falseval->vtype) {
1446         /* error("ternary with different types on the two sides"); */
1447         return false;
1448     }
1449
1450     /* create PHI */
1451     phi = ir_block_create_phi(merge, ast_function_label(func, "phi"), trueval->vtype);
1452     if (!phi ||
1453         !ir_phi_add(phi, ontrue,  trueval) ||
1454         !ir_phi_add(phi, onfalse, falseval))
1455     {
1456         return false;
1457     }
1458
1459     self->phi_out = ir_phi_value(phi);
1460     *out = self->phi_out;
1461
1462     return true;
1463 }
1464
1465 bool ast_loop_codegen(ast_loop *self, ast_function *func, bool lvalue, ir_value **out)
1466 {
1467     ast_expression_codegen *cgen;
1468
1469     ir_value *dummy      = NULL;
1470     ir_value *precond    = NULL;
1471     ir_value *postcond   = NULL;
1472
1473     /* Since we insert some jumps "late" so we have blocks
1474      * ordered "nicely", we need to keep track of the actual end-blocks
1475      * of expressions to add the jumps to.
1476      */
1477     ir_block *bbody      = NULL, *end_bbody      = NULL;
1478     ir_block *bprecond   = NULL, *end_bprecond   = NULL;
1479     ir_block *bpostcond  = NULL, *end_bpostcond  = NULL;
1480     ir_block *bincrement = NULL, *end_bincrement = NULL;
1481     ir_block *bout       = NULL, *bin            = NULL;
1482
1483     /* let's at least move the outgoing block to the end */
1484     size_t    bout_id;
1485
1486     /* 'break' and 'continue' need to be able to find the right blocks */
1487     ir_block *bcontinue     = NULL;
1488     ir_block *bbreak        = NULL;
1489
1490     ir_block *old_bcontinue = NULL;
1491     ir_block *old_bbreak    = NULL;
1492
1493     ir_block *tmpblock      = NULL;
1494
1495     (void)lvalue;
1496     (void)out;
1497
1498     if (self->expression.outr) {
1499         asterror(ast_ctx(self), "internal error: ast_loop cannot be reused, it bears no result!\n");
1500         return false;
1501     }
1502     self->expression.outr = (ir_value*)1;
1503
1504     /* NOTE:
1505      * Should we ever need some kind of block ordering, better make this function
1506      * move blocks around than write a block ordering algorithm later... after all
1507      * the ast and ir should work together, not against each other.
1508      */
1509
1510     /* initexpr doesn't get its own block, it's pointless, it could create more blocks
1511      * anyway if for example it contains a ternary.
1512      */
1513     if (self->initexpr)
1514     {
1515         cgen = self->initexpr->expression.codegen;
1516         if (!(*cgen)((ast_expression*)(self->initexpr), func, false, &dummy))
1517             return false;
1518     }
1519
1520     /* Store the block from which we enter this chaos */
1521     bin = func->curblock;
1522
1523     /* The pre-loop condition needs its own block since we
1524      * need to be able to jump to the start of that expression.
1525      */
1526     if (self->precond)
1527     {
1528         bprecond = ir_function_create_block(func->ir_func, ast_function_label(func, "pre_loop_cond"));
1529         if (!bprecond)
1530             return false;
1531
1532         /* the pre-loop-condition the least important place to 'continue' at */
1533         bcontinue = bprecond;
1534
1535         /* enter */
1536         func->curblock = bprecond;
1537
1538         /* generate */
1539         cgen = self->precond->expression.codegen;
1540         if (!(*cgen)((ast_expression*)(self->precond), func, false, &precond))
1541             return false;
1542
1543         end_bprecond = func->curblock;
1544     } else {
1545         bprecond = end_bprecond = NULL;
1546     }
1547
1548     /* Now the next blocks won't be ordered nicely, but we need to
1549      * generate them this early for 'break' and 'continue'.
1550      */
1551     if (self->increment) {
1552         bincrement = ir_function_create_block(func->ir_func, ast_function_label(func, "loop_increment"));
1553         if (!bincrement)
1554             return false;
1555         bcontinue = bincrement; /* increment comes before the pre-loop-condition */
1556     } else {
1557         bincrement = end_bincrement = NULL;
1558     }
1559
1560     if (self->postcond) {
1561         bpostcond = ir_function_create_block(func->ir_func, ast_function_label(func, "post_loop_cond"));
1562         if (!bpostcond)
1563             return false;
1564         bcontinue = bpostcond; /* postcond comes before the increment */
1565     } else {
1566         bpostcond = end_bpostcond = NULL;
1567     }
1568
1569     bout_id = func->ir_func->blocks_count;
1570     bout = ir_function_create_block(func->ir_func, ast_function_label(func, "after_loop"));
1571     if (!bout)
1572         return false;
1573     bbreak = bout;
1574
1575     /* The loop body... */
1576     if (self->body)
1577     {
1578         bbody = ir_function_create_block(func->ir_func, ast_function_label(func, "loop_body"));
1579         if (!bbody)
1580             return false;
1581
1582         /* enter */
1583         func->curblock = bbody;
1584
1585         old_bbreak          = func->breakblock;
1586         old_bcontinue       = func->continueblock;
1587         func->breakblock    = bbreak;
1588         func->continueblock = bcontinue;
1589
1590         /* generate */
1591         cgen = self->body->expression.codegen;
1592         if (!(*cgen)((ast_expression*)(self->body), func, false, &dummy))
1593             return false;
1594
1595         end_bbody = func->curblock;
1596         func->breakblock    = old_bbreak;
1597         func->continueblock = old_bcontinue;
1598     }
1599
1600     /* post-loop-condition */
1601     if (self->postcond)
1602     {
1603         /* enter */
1604         func->curblock = bpostcond;
1605
1606         /* generate */
1607         cgen = self->postcond->expression.codegen;
1608         if (!(*cgen)((ast_expression*)(self->postcond), func, false, &postcond))
1609             return false;
1610
1611         end_bpostcond = func->curblock;
1612     }
1613
1614     /* The incrementor */
1615     if (self->increment)
1616     {
1617         /* enter */
1618         func->curblock = bincrement;
1619
1620         /* generate */
1621         cgen = self->increment->expression.codegen;
1622         if (!(*cgen)((ast_expression*)(self->increment), func, false, &dummy))
1623             return false;
1624
1625         end_bincrement = func->curblock;
1626     }
1627
1628     /* In any case now, we continue from the outgoing block */
1629     func->curblock = bout;
1630
1631     /* Now all blocks are in place */
1632     /* From 'bin' we jump to whatever comes first */
1633     if      (bprecond)   tmpblock = bprecond;
1634     else if (bbody)      tmpblock = bbody;
1635     else if (bpostcond)  tmpblock = bpostcond;
1636     else                 tmpblock = bout;
1637     if (!ir_block_create_jump(bin, tmpblock))
1638         return false;
1639
1640     /* From precond */
1641     if (bprecond)
1642     {
1643         ir_block *ontrue, *onfalse;
1644         if      (bbody)      ontrue = bbody;
1645         else if (bincrement) ontrue = bincrement;
1646         else if (bpostcond)  ontrue = bpostcond;
1647         else                 ontrue = bprecond;
1648         onfalse = bout;
1649         if (!ir_block_create_if(end_bprecond, precond, ontrue, onfalse))
1650             return false;
1651     }
1652
1653     /* from body */
1654     if (bbody)
1655     {
1656         if      (bincrement) tmpblock = bincrement;
1657         else if (bpostcond)  tmpblock = bpostcond;
1658         else if (bprecond)   tmpblock = bprecond;
1659         else                 tmpblock = bout;
1660         if (!end_bbody->final && !ir_block_create_jump(end_bbody, tmpblock))
1661             return false;
1662     }
1663
1664     /* from increment */
1665     if (bincrement)
1666     {
1667         if      (bpostcond)  tmpblock = bpostcond;
1668         else if (bprecond)   tmpblock = bprecond;
1669         else if (bbody)      tmpblock = bbody;
1670         else                 tmpblock = bout;
1671         if (!ir_block_create_jump(end_bincrement, tmpblock))
1672             return false;
1673     }
1674
1675     /* from postcond */
1676     if (bpostcond)
1677     {
1678         ir_block *ontrue, *onfalse;
1679         if      (bprecond)   ontrue = bprecond;
1680         else if (bbody)      ontrue = bbody;
1681         else if (bincrement) ontrue = bincrement;
1682         else                 ontrue = bpostcond;
1683         onfalse = bout;
1684         if (!ir_block_create_if(end_bpostcond, postcond, ontrue, onfalse))
1685             return false;
1686     }
1687
1688     /* Move 'bout' to the end */
1689     if (!ir_function_blocks_remove(func->ir_func, bout_id) ||
1690         !ir_function_blocks_add(func->ir_func, bout))
1691     {
1692         ir_block_delete(bout);
1693         return false;
1694     }
1695
1696     return true;
1697 }
1698
1699 bool ast_call_codegen(ast_call *self, ast_function *func, bool lvalue, ir_value **out)
1700 {
1701     ast_expression_codegen *cgen;
1702     ir_value_vector         params;
1703     ir_instr               *callinstr;
1704     size_t i;
1705
1706     ir_value *funval = NULL;
1707
1708     /* return values are never lvalues */
1709     (void)lvalue;
1710
1711     if (self->expression.outr) {
1712         *out = self->expression.outr;
1713         return true;
1714     }
1715
1716     cgen = self->func->expression.codegen;
1717     if (!(*cgen)((ast_expression*)(self->func), func, false, &funval))
1718         return false;
1719     if (!funval)
1720         return false;
1721
1722     MEM_VECTOR_INIT(&params, v);
1723
1724     /* parameters */
1725     for (i = 0; i < self->params_count; ++i)
1726     {
1727         ir_value *param;
1728         ast_expression *expr = self->params[i];
1729
1730         cgen = expr->expression.codegen;
1731         if (!(*cgen)(expr, func, false, &param))
1732             goto error;
1733         if (!param)
1734             goto error;
1735         if (!ir_value_vector_v_add(&params, param))
1736             goto error;
1737     }
1738
1739     callinstr = ir_block_create_call(func->curblock, ast_function_label(func, "call"), funval);
1740     if (!callinstr)
1741         goto error;
1742
1743     for (i = 0; i < params.v_count; ++i) {
1744         if (!ir_call_param(callinstr, params.v[i]))
1745             goto error;
1746     }
1747
1748     *out = ir_call_value(callinstr);
1749     self->expression.outr = *out;
1750
1751     MEM_VECTOR_CLEAR(&params, v);
1752     return true;
1753 error:
1754     MEM_VECTOR_CLEAR(&params, v);
1755     return false;
1756 }