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