Only classify several expressions as constant if no error is involved.
[cparser] / ast.c
1 /*
2  * This file is part of cparser.
3  * Copyright (C) 2007-2009 Matthias Braun <matze@braunis.de>
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU General Public License
7  * as published by the Free Software Foundation; either version 2
8  * of the License, or (at your option) any later version.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
18  * 02111-1307, USA.
19  */
20 #include <config.h>
21
22 #include "ast_t.h"
23 #include "symbol_t.h"
24 #include "type_t.h"
25 #include "parser.h"
26 #include "lang_features.h"
27 #include "entity_t.h"
28 #include "printer.h"
29 #include "types.h"
30
31 #include <assert.h>
32 #include <stdio.h>
33 #include <stdlib.h>
34 #include <ctype.h>
35
36 #if defined(__INTEL_COMPILER)
37 #include <mathimf.h>
38 #elif defined(__CYGWIN__)
39 #include "win32/cygwin_math_ext.h"
40 #else
41 #include <math.h>
42 #endif
43
44 #include "adt/error.h"
45 #include "adt/util.h"
46
47 struct obstack ast_obstack;
48
49 static int indent;
50 static int case_indent;
51
52 bool print_implicit_casts = false;
53 bool print_parenthesis = false;
54
55 static void print_statement(const statement_t *statement);
56 static void print_expression_prec(const expression_t *expression, unsigned prec);
57
58 void change_indent(int delta)
59 {
60         indent += delta;
61         assert(indent >= 0);
62 }
63
64 void print_indent(void)
65 {
66         for (int i = 0; i < indent; ++i)
67                 print_char('\t');
68 }
69
70 /**
71  * Returns 1 if a given precedence level has right-to-left
72  * associativity, else 0.
73  *
74  * @param precedence   the operator precedence
75  */
76 static int right_to_left(unsigned precedence)
77 {
78         switch (precedence) {
79         case PREC_ASSIGNMENT:
80         case PREC_CONDITIONAL:
81         case PREC_UNARY:
82                 return 1;
83
84         default:
85                 return 0;
86         }
87 }
88
89 /**
90  * Return the precedence of an expression given by its kind.
91  *
92  * @param kind   the expression kind
93  */
94 static unsigned get_expression_precedence(expression_kind_t kind)
95 {
96         static const unsigned prec[] = {
97                 [EXPR_ERROR]                      = PREC_PRIMARY,
98                 [EXPR_REFERENCE]                  = PREC_PRIMARY,
99                 [EXPR_ENUM_CONSTANT]              = PREC_PRIMARY,
100                 [EXPR_LITERAL_INTEGER]            = PREC_PRIMARY,
101                 [EXPR_LITERAL_FLOATINGPOINT]      = PREC_PRIMARY,
102                 [EXPR_LITERAL_CHARACTER]          = PREC_PRIMARY,
103                 [EXPR_LITERAL_MS_NOOP]            = PREC_PRIMARY,
104                 [EXPR_STRING_LITERAL]             = PREC_PRIMARY,
105                 [EXPR_COMPOUND_LITERAL]           = PREC_UNARY,
106                 [EXPR_CALL]                       = PREC_POSTFIX,
107                 [EXPR_CONDITIONAL]                = PREC_CONDITIONAL,
108                 [EXPR_SELECT]                     = PREC_POSTFIX,
109                 [EXPR_ARRAY_ACCESS]               = PREC_POSTFIX,
110                 [EXPR_SIZEOF]                     = PREC_UNARY,
111                 [EXPR_CLASSIFY_TYPE]              = PREC_UNARY,
112                 [EXPR_ALIGNOF]                    = PREC_UNARY,
113
114                 [EXPR_FUNCNAME]                   = PREC_PRIMARY,
115                 [EXPR_BUILTIN_CONSTANT_P]         = PREC_PRIMARY,
116                 [EXPR_BUILTIN_TYPES_COMPATIBLE_P] = PREC_PRIMARY,
117                 [EXPR_OFFSETOF]                   = PREC_PRIMARY,
118                 [EXPR_VA_START]                   = PREC_PRIMARY,
119                 [EXPR_VA_ARG]                     = PREC_PRIMARY,
120                 [EXPR_VA_COPY]                    = PREC_PRIMARY,
121                 [EXPR_STATEMENT]                  = PREC_PRIMARY,
122                 [EXPR_LABEL_ADDRESS]              = PREC_PRIMARY,
123
124                 [EXPR_UNARY_NEGATE]               = PREC_UNARY,
125                 [EXPR_UNARY_PLUS]                 = PREC_UNARY,
126                 [EXPR_UNARY_BITWISE_NEGATE]       = PREC_UNARY,
127                 [EXPR_UNARY_NOT]                  = PREC_UNARY,
128                 [EXPR_UNARY_DEREFERENCE]          = PREC_UNARY,
129                 [EXPR_UNARY_TAKE_ADDRESS]         = PREC_UNARY,
130                 [EXPR_UNARY_POSTFIX_INCREMENT]    = PREC_POSTFIX,
131                 [EXPR_UNARY_POSTFIX_DECREMENT]    = PREC_POSTFIX,
132                 [EXPR_UNARY_PREFIX_INCREMENT]     = PREC_UNARY,
133                 [EXPR_UNARY_PREFIX_DECREMENT]     = PREC_UNARY,
134                 [EXPR_UNARY_CAST]                 = PREC_UNARY,
135                 [EXPR_UNARY_ASSUME]               = PREC_PRIMARY,
136                 [EXPR_UNARY_DELETE]               = PREC_UNARY,
137                 [EXPR_UNARY_DELETE_ARRAY]         = PREC_UNARY,
138                 [EXPR_UNARY_THROW]                = PREC_ASSIGNMENT,
139
140                 [EXPR_BINARY_ADD]                 = PREC_ADDITIVE,
141                 [EXPR_BINARY_SUB]                 = PREC_ADDITIVE,
142                 [EXPR_BINARY_MUL]                 = PREC_MULTIPLICATIVE,
143                 [EXPR_BINARY_DIV]                 = PREC_MULTIPLICATIVE,
144                 [EXPR_BINARY_MOD]                 = PREC_MULTIPLICATIVE,
145                 [EXPR_BINARY_EQUAL]               = PREC_EQUALITY,
146                 [EXPR_BINARY_NOTEQUAL]            = PREC_EQUALITY,
147                 [EXPR_BINARY_LESS]                = PREC_RELATIONAL,
148                 [EXPR_BINARY_LESSEQUAL]           = PREC_RELATIONAL,
149                 [EXPR_BINARY_GREATER]             = PREC_RELATIONAL,
150                 [EXPR_BINARY_GREATEREQUAL]        = PREC_RELATIONAL,
151                 [EXPR_BINARY_BITWISE_AND]         = PREC_AND,
152                 [EXPR_BINARY_BITWISE_OR]          = PREC_OR,
153                 [EXPR_BINARY_BITWISE_XOR]         = PREC_XOR,
154                 [EXPR_BINARY_LOGICAL_AND]         = PREC_LOGICAL_AND,
155                 [EXPR_BINARY_LOGICAL_OR]          = PREC_LOGICAL_OR,
156                 [EXPR_BINARY_SHIFTLEFT]           = PREC_SHIFT,
157                 [EXPR_BINARY_SHIFTRIGHT]          = PREC_SHIFT,
158                 [EXPR_BINARY_ASSIGN]              = PREC_ASSIGNMENT,
159                 [EXPR_BINARY_MUL_ASSIGN]          = PREC_ASSIGNMENT,
160                 [EXPR_BINARY_DIV_ASSIGN]          = PREC_ASSIGNMENT,
161                 [EXPR_BINARY_MOD_ASSIGN]          = PREC_ASSIGNMENT,
162                 [EXPR_BINARY_ADD_ASSIGN]          = PREC_ASSIGNMENT,
163                 [EXPR_BINARY_SUB_ASSIGN]          = PREC_ASSIGNMENT,
164                 [EXPR_BINARY_SHIFTLEFT_ASSIGN]    = PREC_ASSIGNMENT,
165                 [EXPR_BINARY_SHIFTRIGHT_ASSIGN]   = PREC_ASSIGNMENT,
166                 [EXPR_BINARY_BITWISE_AND_ASSIGN]  = PREC_ASSIGNMENT,
167                 [EXPR_BINARY_BITWISE_XOR_ASSIGN]  = PREC_ASSIGNMENT,
168                 [EXPR_BINARY_BITWISE_OR_ASSIGN]   = PREC_ASSIGNMENT,
169                 [EXPR_BINARY_COMMA]               = PREC_EXPRESSION,
170
171                 [EXPR_BINARY_ISGREATER]           = PREC_PRIMARY,
172                 [EXPR_BINARY_ISGREATEREQUAL]      = PREC_PRIMARY,
173                 [EXPR_BINARY_ISLESS]              = PREC_PRIMARY,
174                 [EXPR_BINARY_ISLESSEQUAL]         = PREC_PRIMARY,
175                 [EXPR_BINARY_ISLESSGREATER]       = PREC_PRIMARY,
176                 [EXPR_BINARY_ISUNORDERED]         = PREC_PRIMARY
177         };
178         assert((size_t)kind < lengthof(prec));
179         unsigned res = prec[kind];
180
181         assert(res != PREC_BOTTOM);
182         return res;
183 }
184
185 /**
186  * Print a quoted string constant.
187  *
188  * @param string  the string constant
189  * @param border  the border char
190  */
191 static void print_quoted_string(const string_t *const string, char border)
192 {
193         print_string(get_string_encoding_prefix(string->encoding));
194
195         print_char(border);
196         const char *end = string->begin + string->size;
197         for (const char *c = string->begin; c != end; ++c) {
198                 const char tc = *c;
199                 if (tc == border) {
200                         print_char('\\');
201                 }
202                 switch (tc) {
203                 case '\\': print_string("\\\\"); break;
204                 case '\a': print_string("\\a"); break;
205                 case '\b': print_string("\\b"); break;
206                 case '\f': print_string("\\f"); break;
207                 case '\n': print_string("\\n"); break;
208                 case '\r': print_string("\\r"); break;
209                 case '\t': print_string("\\t"); break;
210                 case '\v': print_string("\\v"); break;
211                 case '\?': print_string("\\?"); break;
212                 case 27:
213                         if (c_mode & _GNUC) {
214                                 print_string("\\e"); break;
215                         }
216                         /* FALLTHROUGH */
217                 default:
218                         if ((unsigned)tc < 0x80 && !isprint(tc)) {
219                                 print_format("\\%03o", (unsigned)tc);
220                         } else {
221                                 print_char(tc);
222                         }
223                         break;
224                 }
225         }
226         print_char(border);
227 }
228
229 static void print_string_literal(string_literal_expression_t const *const literal, char const delimiter)
230 {
231         print_quoted_string(&literal->value, delimiter);
232 }
233
234 static void print_literal(const literal_expression_t *literal)
235 {
236         switch (literal->base.kind) {
237         case EXPR_LITERAL_MS_NOOP:
238                 print_string("__noop");
239                 return;
240
241         case EXPR_LITERAL_BOOLEAN:
242         case EXPR_LITERAL_FLOATINGPOINT:
243         case EXPR_LITERAL_INTEGER:
244                 print_string(literal->value.begin);
245                 return;
246
247         default:
248                 break;
249         }
250         print_string("INVALID LITERAL KIND");
251 }
252
253 /**
254  * Prints a predefined symbol.
255  */
256 static void print_funcname(const funcname_expression_t *funcname)
257 {
258         const char *s = "";
259         switch (funcname->kind) {
260         case FUNCNAME_FUNCTION:        s = (c_mode & _C99) ? "__func__" : "__FUNCTION__"; break;
261         case FUNCNAME_PRETTY_FUNCTION: s = "__PRETTY_FUNCTION__"; break;
262         case FUNCNAME_FUNCSIG:         s = "__FUNCSIG__"; break;
263         case FUNCNAME_FUNCDNAME:       s = "__FUNCDNAME__"; break;
264         }
265         print_string(s);
266 }
267
268 static void print_compound_literal(
269                 const compound_literal_expression_t *expression)
270 {
271         print_char('(');
272         print_type(expression->type);
273         print_char(')');
274         print_initializer(expression->initializer);
275 }
276
277 static void print_assignment_expression(const expression_t *const expr)
278 {
279         print_expression_prec(expr, PREC_ASSIGNMENT);
280 }
281
282 /**
283  * Prints a call expression.
284  *
285  * @param call  the call expression
286  */
287 static void print_call_expression(const call_expression_t *call)
288 {
289         print_expression_prec(call->function, PREC_POSTFIX);
290         print_char('(');
291         char const *sep = "";
292         for (call_argument_t const *arg = call->arguments; arg; arg = arg->next) {
293                 print_string(sep);
294                 sep = ", ";
295                 print_assignment_expression(arg->expression);
296         }
297         print_char(')');
298 }
299
300 /**
301  * Prints a binary expression.
302  *
303  * @param binexpr   the binary expression
304  */
305 static void print_binary_expression(const binary_expression_t *binexpr)
306 {
307         unsigned prec = get_expression_precedence(binexpr->base.kind);
308         int      r2l  = right_to_left(prec);
309
310         print_expression_prec(binexpr->left, prec + r2l);
311         char const* op;
312         switch (binexpr->base.kind) {
313         case EXPR_BINARY_COMMA:              op = ", ";    break;
314         case EXPR_BINARY_ASSIGN:             op = " = ";   break;
315         case EXPR_BINARY_ADD:                op = " + ";   break;
316         case EXPR_BINARY_SUB:                op = " - ";   break;
317         case EXPR_BINARY_MUL:                op = " * ";   break;
318         case EXPR_BINARY_MOD:                op = " % ";   break;
319         case EXPR_BINARY_DIV:                op = " / ";   break;
320         case EXPR_BINARY_BITWISE_OR:         op = " | ";   break;
321         case EXPR_BINARY_BITWISE_AND:        op = " & ";   break;
322         case EXPR_BINARY_BITWISE_XOR:        op = " ^ ";   break;
323         case EXPR_BINARY_LOGICAL_OR:         op = " || ";  break;
324         case EXPR_BINARY_LOGICAL_AND:        op = " && ";  break;
325         case EXPR_BINARY_NOTEQUAL:           op = " != ";  break;
326         case EXPR_BINARY_EQUAL:              op = " == ";  break;
327         case EXPR_BINARY_LESS:               op = " < ";   break;
328         case EXPR_BINARY_LESSEQUAL:          op = " <= ";  break;
329         case EXPR_BINARY_GREATER:            op = " > ";   break;
330         case EXPR_BINARY_GREATEREQUAL:       op = " >= ";  break;
331         case EXPR_BINARY_SHIFTLEFT:          op = " << ";  break;
332         case EXPR_BINARY_SHIFTRIGHT:         op = " >> ";  break;
333
334         case EXPR_BINARY_ADD_ASSIGN:         op = " += ";  break;
335         case EXPR_BINARY_SUB_ASSIGN:         op = " -= ";  break;
336         case EXPR_BINARY_MUL_ASSIGN:         op = " *= ";  break;
337         case EXPR_BINARY_MOD_ASSIGN:         op = " %= ";  break;
338         case EXPR_BINARY_DIV_ASSIGN:         op = " /= ";  break;
339         case EXPR_BINARY_BITWISE_OR_ASSIGN:  op = " |= ";  break;
340         case EXPR_BINARY_BITWISE_AND_ASSIGN: op = " &= ";  break;
341         case EXPR_BINARY_BITWISE_XOR_ASSIGN: op = " ^= ";  break;
342         case EXPR_BINARY_SHIFTLEFT_ASSIGN:   op = " <<= "; break;
343         case EXPR_BINARY_SHIFTRIGHT_ASSIGN:  op = " >>= "; break;
344         default: panic("invalid binexpression found");
345         }
346         print_string(op);
347         print_expression_prec(binexpr->right, prec + 1 - r2l);
348 }
349
350 /**
351  * Prints an unary expression.
352  *
353  * @param unexpr   the unary expression
354  */
355 static void print_unary_expression(const unary_expression_t *unexpr)
356 {
357         unsigned prec = get_expression_precedence(unexpr->base.kind);
358         switch (unexpr->base.kind) {
359         case EXPR_UNARY_NEGATE:           print_char  ('-' ); break;
360         case EXPR_UNARY_PLUS:             print_char  ('+' ); break;
361         case EXPR_UNARY_NOT:              print_char  ('!' ); break;
362         case EXPR_UNARY_BITWISE_NEGATE:   print_char  ('~' ); break;
363         case EXPR_UNARY_PREFIX_INCREMENT: print_string("++"); break;
364         case EXPR_UNARY_PREFIX_DECREMENT: print_string("--"); break;
365         case EXPR_UNARY_DEREFERENCE:      print_char  ('*' ); break;
366         case EXPR_UNARY_TAKE_ADDRESS:     print_char  ('&' ); break;
367         case EXPR_UNARY_DELETE:           print_string("delete "); break;
368         case EXPR_UNARY_DELETE_ARRAY:     print_string("delete [] "); break;
369
370         case EXPR_UNARY_POSTFIX_INCREMENT:
371                 print_expression_prec(unexpr->value, prec);
372                 print_string("++");
373                 return;
374         case EXPR_UNARY_POSTFIX_DECREMENT:
375                 print_expression_prec(unexpr->value, prec);
376                 print_string("--");
377                 return;
378         case EXPR_UNARY_CAST:
379                 print_char('(');
380                 print_type(unexpr->base.type);
381                 print_char(')');
382                 break;
383         case EXPR_UNARY_ASSUME:
384                 print_string("__assume(");
385                 print_assignment_expression(unexpr->value);
386                 print_char(')');
387                 return;
388
389         case EXPR_UNARY_THROW:
390                 if (unexpr->value == NULL) {
391                         print_string("throw");
392                         return;
393                 }
394                 print_string("throw ");
395                 break;
396
397         default:
398                 panic("invalid unary expression found");
399         }
400         print_expression_prec(unexpr->value, prec);
401 }
402
403 /**
404  * Prints a reference expression.
405  *
406  * @param ref   the reference expression
407  */
408 static void print_reference_expression(const reference_expression_t *ref)
409 {
410         print_string(ref->entity->base.symbol->string);
411 }
412
413 /**
414  * Prints a label address expression.
415  *
416  * @param ref   the reference expression
417  */
418 static void print_label_address_expression(const label_address_expression_t *le)
419 {
420         print_format("&&%s", le->label->base.symbol->string);
421 }
422
423 /**
424  * Prints an array expression.
425  *
426  * @param expression   the array expression
427  */
428 static void print_array_expression(const array_access_expression_t *expression)
429 {
430         if (!expression->flipped) {
431                 print_expression_prec(expression->array_ref, PREC_POSTFIX);
432                 print_char('[');
433                 print_expression(expression->index);
434                 print_char(']');
435         } else {
436                 print_expression_prec(expression->index, PREC_POSTFIX);
437                 print_char('[');
438                 print_expression(expression->array_ref);
439                 print_char(']');
440         }
441 }
442
443 /**
444  * Prints a typeproperty expression (sizeof or __alignof__).
445  *
446  * @param expression   the type property expression
447  */
448 static void print_typeprop_expression(const typeprop_expression_t *expression)
449 {
450         switch (expression->base.kind) {
451         case EXPR_SIZEOF:  print_string("sizeof");                                   break;
452         case EXPR_ALIGNOF: print_string(c_mode & _C11 ? "_Alignof" : "__alignof__"); break;
453         default:           panic("invalid typeprop kind");
454         }
455         if (expression->tp_expression != NULL) {
456                 /* PREC_TOP: always print the '()' here, sizeof x is right but unusual */
457                 print_expression_prec(expression->tp_expression, PREC_TOP);
458         } else {
459                 print_char('(');
460                 print_type(expression->type);
461                 print_char(')');
462         }
463 }
464
465 /**
466  * Prints a builtin constant expression.
467  *
468  * @param expression   the builtin constant expression
469  */
470 static void print_builtin_constant(const builtin_constant_expression_t *expression)
471 {
472         print_string("__builtin_constant_p(");
473         print_assignment_expression(expression->value);
474         print_char(')');
475 }
476
477 /**
478  * Prints a builtin types compatible expression.
479  *
480  * @param expression   the builtin types compatible expression
481  */
482 static void print_builtin_types_compatible(
483                 const builtin_types_compatible_expression_t *expression)
484 {
485         print_string("__builtin_types_compatible_p(");
486         print_type(expression->left);
487         print_string(", ");
488         print_type(expression->right);
489         print_char(')');
490 }
491
492 /**
493  * Prints a conditional expression.
494  *
495  * @param expression   the conditional expression
496  */
497 static void print_conditional(const conditional_expression_t *expression)
498 {
499         print_expression_prec(expression->condition, PREC_LOGICAL_OR);
500         if (expression->true_expression != NULL) {
501                 print_string(" ? ");
502                 print_expression_prec(expression->true_expression, PREC_EXPRESSION);
503                 print_string(" : ");
504         } else {
505                 print_string(" ?: ");
506         }
507         precedence_t prec = c_mode & _CXX ? PREC_ASSIGNMENT : PREC_CONDITIONAL;
508         print_expression_prec(expression->false_expression, prec);
509 }
510
511 /**
512  * Prints a va_start expression.
513  *
514  * @param expression   the va_start expression
515  */
516 static void print_va_start(const va_start_expression_t *const expression)
517 {
518         print_string("__builtin_va_start(");
519         print_assignment_expression(expression->ap);
520         print_string(", ");
521         print_assignment_expression(expression->parameter);
522         print_char(')');
523 }
524
525 /**
526  * Prints a va_arg expression.
527  *
528  * @param expression   the va_arg expression
529  */
530 static void print_va_arg(const va_arg_expression_t *expression)
531 {
532         print_string("__builtin_va_arg(");
533         print_assignment_expression(expression->ap);
534         print_string(", ");
535         print_type(expression->base.type);
536         print_char(')');
537 }
538
539 /**
540  * Prints a va_copy expression.
541  *
542  * @param expression   the va_copy expression
543  */
544 static void print_va_copy(const va_copy_expression_t *expression)
545 {
546         print_string("__builtin_va_copy(");
547         print_assignment_expression(expression->dst);
548         print_string(", ");
549         print_assignment_expression(expression->src);
550         print_char(')');
551 }
552
553 /**
554  * Prints a select expression (. or ->).
555  *
556  * @param expression   the select expression
557  */
558 static void print_select(const select_expression_t *expression)
559 {
560         print_expression_prec(expression->compound, PREC_POSTFIX);
561         /* do not print anything for anonymous struct/union selects
562          * FIXME: if the anonymous select was a '->' this will print '.'
563          */
564         if (expression->compound_entry->base.symbol == NULL)
565                 return;
566
567         if (is_type_pointer(skip_typeref(expression->compound->base.type))) {
568                 print_string("->");
569         } else {
570                 print_char('.');
571         }
572         print_string(expression->compound_entry->base.symbol->string);
573 }
574
575 /**
576  * Prints a type classify expression.
577  *
578  * @param expr   the type classify expression
579  */
580 static void print_classify_type_expression(
581         const classify_type_expression_t *const expr)
582 {
583         print_string("__builtin_classify_type(");
584         print_assignment_expression(expr->type_expression);
585         print_char(')');
586 }
587
588 /**
589  * Prints a designator.
590  *
591  * @param designator  the designator
592  */
593 static void print_designator(const designator_t *designator)
594 {
595         for ( ; designator != NULL; designator = designator->next) {
596                 if (designator->symbol == NULL) {
597                         print_char('[');
598                         print_expression(designator->array_index);
599                         print_char(']');
600                 } else {
601                         print_char('.');
602                         print_string(designator->symbol->string);
603                 }
604         }
605 }
606
607 /**
608  * Prints an offsetof expression.
609  *
610  * @param expression   the offset expression
611  */
612 static void print_offsetof_expression(const offsetof_expression_t *expression)
613 {
614         print_string("__builtin_offsetof(");
615         print_type(expression->type);
616         print_char(',');
617         print_designator(expression->designator);
618         print_char(')');
619 }
620
621 /**
622  * Prints a statement expression.
623  *
624  * @param expression   the statement expression
625  */
626 static void print_statement_expression(const statement_expression_t *expression)
627 {
628         print_char('(');
629         print_statement(expression->statement);
630         print_char(')');
631 }
632
633 static bool needs_parentheses(expression_t const *const expr, unsigned const top_prec)
634 {
635         if (expr->base.parenthesized)
636                 return true;
637
638         if (top_prec > get_expression_precedence(expr->base.kind))
639                 return true;
640
641         if (print_parenthesis && top_prec != PREC_BOTTOM) {
642                 switch (expr->kind) {
643                 case EXPR_ENUM_CONSTANT:
644                 case EXPR_FUNCNAME:
645                 case EXPR_LITERAL_CASES:
646                 case EXPR_LITERAL_CHARACTER:
647                 case EXPR_REFERENCE:
648                 case EXPR_STRING_LITERAL:
649                         /* Do not print () around subexpressions consisting of a single token. */
650                         return false;
651
652                 default:
653                         return true;
654                 }
655         }
656
657         return false;
658 }
659
660 /**
661  * Prints an expression with parenthesis if needed.
662  *
663  * @param expression  the expression to print
664  * @param top_prec    the precedence of the user of this expression.
665  */
666 static void print_expression_prec(expression_t const *expr, unsigned const top_prec)
667 {
668         if (expr->kind == EXPR_UNARY_CAST && expr->base.implicit && !print_implicit_casts) {
669                 expr = expr->unary.value;
670         }
671
672         bool const parenthesized = needs_parentheses(expr, top_prec);
673
674         if (parenthesized)
675                 print_char('(');
676         switch (expr->kind) {
677         case EXPR_ALIGNOF:
678         case EXPR_SIZEOF:                     print_typeprop_expression(     &expr->typeprop);                 break;
679         case EXPR_ARRAY_ACCESS:               print_array_expression(        &expr->array_access);             break;
680         case EXPR_BINARY_CASES:               print_binary_expression(       &expr->binary);                   break;
681         case EXPR_BUILTIN_CONSTANT_P:         print_builtin_constant(        &expr->builtin_constant);         break;
682         case EXPR_BUILTIN_TYPES_COMPATIBLE_P: print_builtin_types_compatible(&expr->builtin_types_compatible); break;
683         case EXPR_CALL:                       print_call_expression(         &expr->call);                     break;
684         case EXPR_CLASSIFY_TYPE:              print_classify_type_expression(&expr->classify_type);            break;
685         case EXPR_COMPOUND_LITERAL:           print_compound_literal(        &expr->compound_literal);         break;
686         case EXPR_CONDITIONAL:                print_conditional(             &expr->conditional);              break;
687         case EXPR_ERROR:                      print_string("$error$");                                         break;
688         case EXPR_FUNCNAME:                   print_funcname(                &expr->funcname);                 break;
689         case EXPR_LABEL_ADDRESS:              print_label_address_expression(&expr->label_address);            break;
690         case EXPR_LITERAL_CASES:              print_literal(                 &expr->literal);                  break;
691         case EXPR_LITERAL_CHARACTER:          print_string_literal(          &expr->string_literal, '\'');     break;
692         case EXPR_OFFSETOF:                   print_offsetof_expression(     &expr->offsetofe);                break;
693         case EXPR_REFERENCE:
694         case EXPR_ENUM_CONSTANT:              print_reference_expression(    &expr->reference);                break;
695         case EXPR_SELECT:                     print_select(                  &expr->select);                   break;
696         case EXPR_STATEMENT:                  print_statement_expression(    &expr->statement);                break;
697         case EXPR_STRING_LITERAL:             print_string_literal(          &expr->string_literal, '"');      break;
698         case EXPR_UNARY_CASES:                print_unary_expression(        &expr->unary);                    break;
699         case EXPR_VA_ARG:                     print_va_arg(                  &expr->va_arge);                  break;
700         case EXPR_VA_COPY:                    print_va_copy(                 &expr->va_copye);                 break;
701         case EXPR_VA_START:                   print_va_start(                &expr->va_starte);                break;
702         }
703         if (parenthesized)
704                 print_char(')');
705 }
706
707 static void print_indented_statement(statement_t const *const stmt)
708 {
709         switch (stmt->kind) {
710         case STATEMENT_LABEL:
711                 break;
712
713         case STATEMENT_CASE_LABEL:
714                 for (int i = 0; i != case_indent; ++i)
715                         print_char('\t');
716                 break;
717
718         default:
719                 print_indent();
720                 break;
721         }
722         print_statement(stmt);
723 }
724
725 /**
726  * Print an compound statement.
727  *
728  * @param block  the compound statement
729  */
730 static void print_compound_statement(const compound_statement_t *block)
731 {
732         print_string("{\n");
733         ++indent;
734
735         for (statement_t const *stmt = block->statements; stmt; stmt = stmt->base.next) {
736                 print_indented_statement(stmt);
737                 print_char('\n');
738         }
739
740         --indent;
741         print_indent();
742         print_char('}');
743 }
744
745 /**
746  * Print a return statement.
747  *
748  * @param statement  the return statement
749  */
750 static void print_return_statement(const return_statement_t *statement)
751 {
752         expression_t const *const val = statement->value;
753         if (val != NULL) {
754                 print_string("return ");
755                 print_expression(val);
756                 print_char(';');
757         } else {
758                 print_string("return;");
759         }
760 }
761
762 /**
763  * Print an expression statement.
764  *
765  * @param statement  the expression statement
766  */
767 static void print_expression_statement(const expression_statement_t *statement)
768 {
769         print_expression(statement->expression);
770         print_char(';');
771 }
772
773 /**
774  * Print a computed goto statement.
775  *
776  * @param statement  the computed goto statement
777  */
778 static void print_computed_goto_statement(computed_goto_statement_t const *const stmt)
779 {
780         print_string("goto *");
781         print_expression(stmt->expression);
782         print_char(';');
783 }
784
785 /**
786  * Print a goto statement.
787  *
788  * @param statement  the goto statement
789  */
790 static void print_goto_statement(const goto_statement_t *statement)
791 {
792         print_string("goto ");
793         print_string(statement->label->base.symbol->string);
794         print_char(';');
795 }
796
797 /**
798  * Print a label statement.
799  *
800  * @param statement  the label statement
801  */
802 static void print_label_statement(const label_statement_t *statement)
803 {
804         print_format("%s:\n", statement->label->base.symbol->string);
805         print_indented_statement(statement->statement);
806 }
807
808 static void print_inner_statement(statement_t const *const stmt)
809 {
810         if (stmt->kind == STATEMENT_COMPOUND) {
811                 print_char(' ');
812                 print_compound_statement(&stmt->compound);
813         } else {
814                 print_char('\n');
815                 ++indent;
816                 print_indented_statement(stmt);
817                 --indent;
818         }
819 }
820
821 static void print_after_inner_statement(statement_t const *const stmt)
822 {
823         if (stmt->kind == STATEMENT_COMPOUND) {
824                 print_char(' ');
825         } else {
826                 print_char('\n');
827                 print_indent();
828         }
829 }
830
831 /**
832  * Print an if statement.
833  *
834  * @param statement  the if statement
835  */
836 static void print_if_statement(const if_statement_t *statement)
837 {
838         print_string("if (");
839         print_expression(statement->condition);
840         print_char(')');
841         print_inner_statement(statement->true_statement);
842
843         statement_t const *const f = statement->false_statement;
844         if (f) {
845                 print_after_inner_statement(statement->true_statement);
846                 print_string("else");
847                 if (f->kind == STATEMENT_IF) {
848                         print_char(' ');
849                         print_if_statement(&f->ifs);
850                 } else {
851                         print_inner_statement(f);
852                 }
853         }
854 }
855
856 /**
857  * Print a switch statement.
858  *
859  * @param statement  the switch statement
860  */
861 static void print_switch_statement(const switch_statement_t *statement)
862 {
863         int const old_case_indent = case_indent;
864         case_indent = indent;
865
866         print_string("switch (");
867         print_expression(statement->expression);
868         print_char(')');
869         print_inner_statement(statement->body);
870
871         case_indent = old_case_indent;
872 }
873
874 /**
875  * Print a case label (including the default label).
876  *
877  * @param statement  the case label statement
878  */
879 static void print_case_label(const case_label_statement_t *statement)
880 {
881         if (statement->expression == NULL) {
882                 print_string("default:\n");
883         } else {
884                 print_string("case ");
885                 print_expression(statement->expression);
886                 if (statement->end_range != NULL) {
887                         print_string(" ... ");
888                         print_expression(statement->end_range);
889                 }
890                 print_string(":\n");
891         }
892         print_indented_statement(statement->statement);
893 }
894
895 static void print_typedef(const entity_t *entity)
896 {
897         print_string("typedef ");
898         print_type_ext(entity->typedefe.type, entity->base.symbol, NULL);
899         print_char(';');
900 }
901
902 /**
903  * returns true if the entity is a compiler generated one and has no real
904  * correspondenc in the source file
905  */
906 static bool is_generated_entity(const entity_t *entity)
907 {
908         if (entity->kind == ENTITY_TYPEDEF)
909                 return entity->typedefe.builtin;
910
911         if (is_declaration(entity))
912                 return entity->declaration.implicit;
913
914         return false;
915 }
916
917 /**
918  * Print a declaration statement.
919  *
920  * @param statement   the statement
921  */
922 static void print_declaration_statement(
923                 const declaration_statement_t *statement)
924 {
925         bool first = true;
926         entity_t *entity = statement->declarations_begin;
927         if (entity == NULL) {
928                 print_string("/* empty declaration statement */");
929                 return;
930         }
931
932         entity_t *const end = statement->declarations_end->base.next;
933         for (; entity != end; entity = entity->base.next) {
934                 if (entity->kind == ENTITY_ENUM_VALUE)
935                         continue;
936                 if (is_generated_entity(entity))
937                         continue;
938
939                 if (!first) {
940                         print_char('\n');
941                         print_indent();
942                 } else {
943                         first = false;
944                 }
945
946                 print_entity(entity);
947         }
948 }
949
950 /**
951  * Print a while statement.
952  *
953  * @param statement   the statement
954  */
955 static void print_while_statement(const while_statement_t *statement)
956 {
957         print_string("while (");
958         print_expression(statement->condition);
959         print_char(')');
960         print_inner_statement(statement->body);
961 }
962
963 /**
964  * Print a do-while statement.
965  *
966  * @param statement   the statement
967  */
968 static void print_do_while_statement(const do_while_statement_t *statement)
969 {
970         print_string("do");
971         print_inner_statement(statement->body);
972         print_after_inner_statement(statement->body);
973         print_string("while (");
974         print_expression(statement->condition);
975         print_string(");");
976 }
977
978 /**
979  * Print a for statement.
980  *
981  * @param statement   the statement
982  */
983 static void print_for_statement(const for_statement_t *statement)
984 {
985         print_string("for (");
986         if (statement->initialisation != NULL) {
987                 print_expression(statement->initialisation);
988                 print_char(';');
989         } else {
990                 entity_t const *entity = statement->scope.entities;
991                 for (; entity != NULL; entity = entity->base.next) {
992                         if (is_generated_entity(entity))
993                                 continue;
994                         /* FIXME display of multiple declarations is wrong */
995                         print_declaration(entity);
996                 }
997         }
998         if (statement->condition != NULL) {
999                 print_char(' ');
1000                 print_expression(statement->condition);
1001         }
1002         print_char(';');
1003         if (statement->step != NULL) {
1004                 print_char(' ');
1005                 print_expression(statement->step);
1006         }
1007         print_char(')');
1008         print_inner_statement(statement->body);
1009 }
1010
1011 /**
1012  * Print assembler arguments.
1013  *
1014  * @param arguments   the arguments
1015  */
1016 static void print_asm_arguments(asm_argument_t *arguments)
1017 {
1018         asm_argument_t *argument = arguments;
1019         for (; argument != NULL; argument = argument->next) {
1020                 if (argument != arguments)
1021                         print_string(", ");
1022
1023                 if (argument->symbol) {
1024                         print_format("[%s] ", argument->symbol->string);
1025                 }
1026                 print_quoted_string(&argument->constraints, '"');
1027                 print_string(" (");
1028                 print_expression(argument->expression);
1029                 print_char(')');
1030         }
1031 }
1032
1033 /**
1034  * Print assembler clobbers.
1035  *
1036  * @param clobbers   the clobbers
1037  */
1038 static void print_asm_clobbers(asm_clobber_t *clobbers)
1039 {
1040         asm_clobber_t *clobber = clobbers;
1041         for (; clobber != NULL; clobber = clobber->next) {
1042                 if (clobber != clobbers)
1043                         print_string(", ");
1044
1045                 print_quoted_string(&clobber->clobber, '"');
1046         }
1047 }
1048
1049 /**
1050  * Print an assembler statement.
1051  *
1052  * @param statement   the statement
1053  */
1054 static void print_asm_statement(const asm_statement_t *statement)
1055 {
1056         print_string("asm ");
1057         if (statement->is_volatile) {
1058                 print_string("volatile ");
1059         }
1060         print_char('(');
1061         print_quoted_string(&statement->asm_text, '"');
1062         if (statement->outputs  == NULL &&
1063             statement->inputs   == NULL &&
1064             statement->clobbers == NULL)
1065                 goto end_of_print_asm_statement;
1066
1067         print_string(" : ");
1068         print_asm_arguments(statement->outputs);
1069         if (statement->inputs == NULL && statement->clobbers == NULL)
1070                 goto end_of_print_asm_statement;
1071
1072         print_string(" : ");
1073         print_asm_arguments(statement->inputs);
1074         if (statement->clobbers == NULL)
1075                 goto end_of_print_asm_statement;
1076
1077         print_string(" : ");
1078         print_asm_clobbers(statement->clobbers);
1079
1080 end_of_print_asm_statement:
1081         print_string(");");
1082 }
1083
1084 /**
1085  * Print a microsoft __try statement.
1086  *
1087  * @param statement   the statement
1088  */
1089 static void print_ms_try_statement(const ms_try_statement_t *statement)
1090 {
1091         print_string("__try");
1092         print_inner_statement(statement->try_statement);
1093         print_after_inner_statement(statement->try_statement);
1094         if (statement->except_expression != NULL) {
1095                 print_string("__except(");
1096                 print_expression(statement->except_expression);
1097                 print_char(')');
1098         } else {
1099                 print_string("__finally");
1100         }
1101         print_inner_statement(statement->final_statement);
1102 }
1103
1104 /**
1105  * Print a microsoft __leave statement.
1106  *
1107  * @param statement   the statement
1108  */
1109 static void print_leave_statement(const leave_statement_t *statement)
1110 {
1111         (void)statement;
1112         print_string("__leave;");
1113 }
1114
1115 /**
1116  * Print a statement.
1117  *
1118  * @param statement   the statement
1119  */
1120 void print_statement(statement_t const *const stmt)
1121 {
1122         switch (stmt->kind) {
1123         case STATEMENT_ASM:           print_asm_statement(          &stmt->asms);          break;
1124         case STATEMENT_BREAK:         print_string("break;");                              break;
1125         case STATEMENT_CASE_LABEL:    print_case_label(             &stmt->case_label);    break;
1126         case STATEMENT_COMPOUND:      print_compound_statement(     &stmt->compound);      break;
1127         case STATEMENT_COMPUTED_GOTO: print_computed_goto_statement(&stmt->computed_goto); break;
1128         case STATEMENT_CONTINUE:      print_string("continue;");                           break;
1129         case STATEMENT_DECLARATION:   print_declaration_statement(  &stmt->declaration);   break;
1130         case STATEMENT_DO_WHILE:      print_do_while_statement(     &stmt->do_while);      break;
1131         case STATEMENT_EMPTY:         print_char(';');                                     break;
1132         case STATEMENT_ERROR:         print_string("$error statement$");                   break;
1133         case STATEMENT_EXPRESSION:    print_expression_statement(   &stmt->expression);    break;
1134         case STATEMENT_FOR:           print_for_statement(          &stmt->fors);          break;
1135         case STATEMENT_GOTO:          print_goto_statement(         &stmt->gotos);         break;
1136         case STATEMENT_IF:            print_if_statement(           &stmt->ifs);           break;
1137         case STATEMENT_LABEL:         print_label_statement(        &stmt->label);         break;
1138         case STATEMENT_LEAVE:         print_leave_statement(        &stmt->leave);         break;
1139         case STATEMENT_MS_TRY:        print_ms_try_statement(       &stmt->ms_try);        break;
1140         case STATEMENT_RETURN:        print_return_statement(       &stmt->returns);       break;
1141         case STATEMENT_SWITCH:        print_switch_statement(       &stmt->switchs);       break;
1142         case STATEMENT_WHILE:         print_while_statement(        &stmt->whiles);        break;
1143         }
1144 }
1145
1146 /**
1147  * Print a storage class.
1148  *
1149  * @param storage_class   the storage class
1150  */
1151 static void print_storage_class(storage_class_tag_t storage_class)
1152 {
1153         switch (storage_class) {
1154         case STORAGE_CLASS_NONE:     return;
1155         case STORAGE_CLASS_TYPEDEF:  print_string("typedef ");  return;
1156         case STORAGE_CLASS_EXTERN:   print_string("extern ");   return;
1157         case STORAGE_CLASS_STATIC:   print_string("static ");   return;
1158         case STORAGE_CLASS_AUTO:     print_string("auto ");     return;
1159         case STORAGE_CLASS_REGISTER: print_string("register "); return;
1160         }
1161         panic("invalid storage class");
1162 }
1163
1164 /**
1165  * Print an initializer.
1166  *
1167  * @param initializer  the initializer
1168  */
1169 void print_initializer(const initializer_t *initializer)
1170 {
1171         if (initializer == NULL) {
1172                 print_string("{}");
1173                 return;
1174         }
1175
1176         switch (initializer->kind) {
1177         case INITIALIZER_STRING:
1178         case INITIALIZER_VALUE:
1179                 print_assignment_expression(initializer->value.value);
1180                 return;
1181
1182         case INITIALIZER_LIST: {
1183                 print_string("{ ");
1184                 const initializer_list_t *list = &initializer->list;
1185
1186                 for (size_t i = 0 ; i < list->len; ++i) {
1187                         const initializer_t *sub_init = list->initializers[i];
1188                         print_initializer(list->initializers[i]);
1189                         if (i < list->len-1) {
1190                                 if (sub_init == NULL || sub_init->kind != INITIALIZER_DESIGNATOR)
1191                                         print_string(", ");
1192                         }
1193                 }
1194                 print_string(" }");
1195                 return;
1196         }
1197
1198         case INITIALIZER_DESIGNATOR:
1199                 print_designator(initializer->designator.designator);
1200                 print_string(" = ");
1201                 return;
1202         }
1203
1204         panic("invalid initializer kind found");
1205 }
1206
1207 #if 0
1208 /**
1209  * Print microsoft extended declaration modifiers.
1210  */
1211 static void print_ms_modifiers(const declaration_t *declaration)
1212 {
1213         if ((c_mode & _MS) == 0)
1214                 return;
1215
1216         decl_modifiers_t modifiers = declaration->modifiers;
1217
1218         bool        ds_shown = false;
1219         const char *next     = "(";
1220
1221         if (declaration->base.kind == ENTITY_VARIABLE) {
1222                 variable_t *variable = (variable_t*)declaration;
1223                 if (variable->alignment != 0
1224                                 || variable->get_property_sym != NULL
1225                                 || variable->put_property_sym != NULL) {
1226                         if (!ds_shown) {
1227                                 print_string("__declspec");
1228                                 ds_shown = true;
1229                         }
1230
1231                         if (variable->alignment != 0) {
1232                                 print_string(next); next = ", "; print_format("align(%u)", variable->alignment);
1233                         }
1234                         if (variable->get_property_sym != NULL
1235                                         || variable->put_property_sym != NULL) {
1236                                 char *comma = "";
1237                                 print_string(next); next = ", "; print_string("property(");
1238                                 if (variable->get_property_sym != NULL) {
1239                                         print_format("get=%s", variable->get_property_sym->string);
1240                                         comma = ", ";
1241                                 }
1242                                 if (variable->put_property_sym != NULL)
1243                                         print_format("%sput=%s", comma, variable->put_property_sym->string);
1244                                 print_char(')');
1245                         }
1246                 }
1247         }
1248
1249         /* DM_FORCEINLINE handled outside. */
1250         if ((modifiers & ~DM_FORCEINLINE) != 0) {
1251                 if (!ds_shown) {
1252                         print_string("__declspec");
1253                         ds_shown = true;
1254                 }
1255                 if (modifiers & DM_DLLIMPORT) {
1256                         print_string(next); next = ", "; print_string("dllimport");
1257                 }
1258                 if (modifiers & DM_DLLEXPORT) {
1259                         print_string(next); next = ", "; print_string("dllexport");
1260                 }
1261                 if (modifiers & DM_THREAD) {
1262                         print_string(next); next = ", "; print_string("thread");
1263                 }
1264                 if (modifiers & DM_NAKED) {
1265                         print_string(next); next = ", "; print_string("naked");
1266                 }
1267                 if (modifiers & DM_THREAD) {
1268                         print_string(next); next = ", "; print_string("thread");
1269                 }
1270                 if (modifiers & DM_SELECTANY) {
1271                         print_string(next); next = ", "; print_string("selectany");
1272                 }
1273                 if (modifiers & DM_NOTHROW) {
1274                         print_string(next); next = ", "; print_string("nothrow");
1275                 }
1276                 if (modifiers & DM_NORETURN) {
1277                         print_string(next); next = ", "; print_string("noreturn");
1278                 }
1279                 if (modifiers & DM_NOINLINE) {
1280                         print_string(next); next = ", "; print_string("noinline");
1281                 }
1282                 if (modifiers & DM_DEPRECATED) {
1283                         print_string(next); next = ", "; print_string("deprecated");
1284                         if (declaration->deprecated_string != NULL)
1285                                 print_format("(\"%s\")",
1286                                         declaration->deprecated_string);
1287                 }
1288                 if (modifiers & DM_RESTRICT) {
1289                         print_string(next); next = ", "; print_string("restrict");
1290                 }
1291                 if (modifiers & DM_NOALIAS) {
1292                         print_string(next); next = ", "; print_string("noalias");
1293                 }
1294         }
1295
1296         if (ds_shown)
1297                 print_string(") ");
1298 }
1299 #endif
1300
1301 static void print_scope(const scope_t *scope)
1302 {
1303         const entity_t *entity = scope->entities;
1304         for ( ; entity != NULL; entity = entity->base.next) {
1305                 print_indent();
1306                 print_entity(entity);
1307                 print_char('\n');
1308         }
1309 }
1310
1311 static void print_namespace(const namespace_t *namespace)
1312 {
1313         print_string("namespace ");
1314         if (namespace->base.symbol != NULL) {
1315                 print_string(namespace->base.symbol->string);
1316                 print_char(' ');
1317         }
1318
1319         print_string("{\n");
1320         ++indent;
1321
1322         print_scope(&namespace->members);
1323
1324         --indent;
1325         print_indent();
1326         print_string("}\n");
1327 }
1328
1329 /**
1330  * Print a variable or function declaration
1331  */
1332 void print_declaration(const entity_t *entity)
1333 {
1334         assert(is_declaration(entity));
1335         const declaration_t *declaration = &entity->declaration;
1336
1337         print_storage_class((storage_class_tag_t)declaration->declared_storage_class);
1338         if (entity->kind == ENTITY_FUNCTION) {
1339                 function_t *function = (function_t*)declaration;
1340                 if (function->is_inline) {
1341                         if (declaration->modifiers & DM_FORCEINLINE) {
1342                                 print_string("__forceinline ");
1343                         } else if (declaration->modifiers & DM_MICROSOFT_INLINE) {
1344                                 print_string("__inline ");
1345                         } else {
1346                                 print_string("inline ");
1347                         }
1348                 }
1349         }
1350         //print_ms_modifiers(declaration);
1351         switch (entity->kind) {
1352                 case ENTITY_FUNCTION:
1353                         print_type_ext(entity->declaration.type, entity->base.symbol,
1354                                         &entity->function.parameters);
1355
1356                         if (entity->function.statement != NULL) {
1357                                 print_char('\n');
1358                                 print_indented_statement(entity->function.statement);
1359                                 print_char('\n');
1360                                 return;
1361                         }
1362                         break;
1363
1364                 case ENTITY_VARIABLE:
1365                         if (entity->variable.thread_local)
1366                                 print_string(c_mode & _C11 ? "_Thread_local " : "__thread ");
1367                         print_type_ext(declaration->type, declaration->base.symbol, NULL);
1368                         if (entity->variable.initializer != NULL) {
1369                                 print_string(" = ");
1370                                 print_initializer(entity->variable.initializer);
1371                         }
1372                         break;
1373
1374                 case ENTITY_COMPOUND_MEMBER:
1375                         print_type_ext(declaration->type, declaration->base.symbol, NULL);
1376                         if (entity->compound_member.bitfield) {
1377                                 print_format(" : %u", entity->compound_member.bit_size);
1378                         }
1379                         break;
1380
1381                 default:
1382                         print_type_ext(declaration->type, declaration->base.symbol, NULL);
1383                         break;
1384         }
1385         print_char(';');
1386 }
1387
1388 /**
1389  * Prints an expression.
1390  *
1391  * @param expression  the expression
1392  */
1393 void print_expression(const expression_t *expression)
1394 {
1395         print_expression_prec(expression, PREC_BOTTOM);
1396 }
1397
1398 /**
1399  * Print a declaration.
1400  *
1401  * @param declaration  the declaration
1402  */
1403 void print_entity(const entity_t *entity)
1404 {
1405         if (entity->base.namespc != NAMESPACE_NORMAL && entity->base.symbol == NULL)
1406                 return;
1407
1408         switch ((entity_kind_tag_t)entity->kind) {
1409         case ENTITY_VARIABLE:
1410         case ENTITY_PARAMETER:
1411         case ENTITY_COMPOUND_MEMBER:
1412         case ENTITY_FUNCTION:
1413                 print_declaration(entity);
1414                 return;
1415         case ENTITY_TYPEDEF:
1416                 print_typedef(entity);
1417                 return;
1418         case ENTITY_CLASS:
1419                 /* TODO */
1420                 print_string("class ");
1421                 print_string(entity->base.symbol->string);
1422                 print_string("; /* TODO */\n");
1423                 return;
1424         case ENTITY_STRUCT:
1425                 print_string("struct ");
1426                 goto print_compound;
1427         case ENTITY_UNION:
1428                 print_string("union ");
1429 print_compound:
1430                 print_string(entity->base.symbol->string);
1431                 if (entity->compound.complete) {
1432                         print_char(' ');
1433                         print_compound_definition(&entity->compound);
1434                 }
1435                 print_char(';');
1436                 return;
1437         case ENTITY_ENUM:
1438                 print_string("enum ");
1439                 print_string(entity->base.symbol->string);
1440                 print_char(' ');
1441                 print_enum_definition(&entity->enume);
1442                 print_char(';');
1443                 return;
1444         case ENTITY_NAMESPACE:
1445                 print_namespace(&entity->namespacee);
1446                 return;
1447         case ENTITY_LOCAL_LABEL:
1448                 print_string("__label__ ");
1449                 print_string(entity->base.symbol->string);
1450                 print_char(';');
1451                 return;
1452         case ENTITY_LABEL:
1453         case ENTITY_ENUM_VALUE:
1454                 panic("print_entity used on unexpected entity type");
1455         }
1456         panic("Invalid entity type encountered");
1457 }
1458
1459 /**
1460  * Print the AST of a translation unit.
1461  *
1462  * @param unit   the translation unit
1463  */
1464 void print_ast(const translation_unit_t *unit)
1465 {
1466         entity_t *entity = unit->scope.entities;
1467         for ( ; entity != NULL; entity = entity->base.next) {
1468                 if (entity->kind == ENTITY_ENUM_VALUE)
1469                         continue;
1470                 if (entity->base.namespc != NAMESPACE_NORMAL
1471                                 && entity->base.symbol == NULL)
1472                         continue;
1473                 if (is_generated_entity(entity))
1474                         continue;
1475
1476                 print_indent();
1477                 print_entity(entity);
1478                 print_char('\n');
1479         }
1480 }
1481
1482 expression_classification_t is_constant_initializer(const initializer_t *initializer)
1483 {
1484         switch (initializer->kind) {
1485         case INITIALIZER_STRING:
1486         case INITIALIZER_DESIGNATOR:
1487                 return EXPR_CLASS_CONSTANT;
1488
1489         case INITIALIZER_VALUE:
1490                 return is_linker_constant(initializer->value.value);
1491
1492         case INITIALIZER_LIST: {
1493                 expression_classification_t all = EXPR_CLASS_CONSTANT;
1494                 for (size_t i = 0; i < initializer->list.len; ++i) {
1495                         initializer_t *sub_initializer = initializer->list.initializers[i];
1496                         expression_classification_t const cur = is_constant_initializer(sub_initializer);
1497                         if (all > cur) {
1498                                 all = cur;
1499                         }
1500                 }
1501                 return all;
1502         }
1503         }
1504         panic("invalid initializer kind found");
1505 }
1506
1507 /**
1508  * Checks if an expression references an object with a constant/known location
1509  * to the linker. Example:
1510  *  - "x", "*&x" with x being a global variable. The value of x need not be
1511  *         constant but the address of x is.
1512  *  - "a.b.c" when a has a constant/known location to the linker
1513  */
1514 static expression_classification_t is_object_with_linker_constant_address(
1515         const expression_t *expression)
1516 {
1517         switch (expression->kind) {
1518         case EXPR_UNARY_DEREFERENCE:
1519                 return is_linker_constant(expression->unary.value);
1520
1521         case EXPR_SELECT: {
1522                 type_t *base_type = skip_typeref(expression->select.compound->base.type);
1523                 if (is_type_pointer(base_type)) {
1524                         /* it's a -> */
1525                         return is_linker_constant(expression->select.compound);
1526                 } else {
1527                         return is_object_with_linker_constant_address(expression->select.compound);
1528                 }
1529         }
1530
1531         case EXPR_ARRAY_ACCESS: {
1532                 expression_classification_t const ref = is_linker_constant(expression->array_access.array_ref);
1533                 expression_classification_t const idx = is_constant_expression(expression->array_access.index);
1534                 return ref < idx ? ref : idx;
1535         }
1536
1537         case EXPR_REFERENCE: {
1538                 entity_t *entity = expression->reference.entity;
1539                 if (!is_declaration(entity))
1540                         return EXPR_CLASS_VARIABLE;
1541
1542                 switch ((storage_class_tag_t)entity->declaration.storage_class) {
1543                 case STORAGE_CLASS_NONE:
1544                 case STORAGE_CLASS_EXTERN:
1545                 case STORAGE_CLASS_STATIC:
1546                         return
1547                                 entity->kind != ENTITY_VARIABLE ||
1548                                 !entity->variable.thread_local ? EXPR_CLASS_CONSTANT :
1549                                 EXPR_CLASS_VARIABLE;
1550
1551                 case STORAGE_CLASS_REGISTER:
1552                 case STORAGE_CLASS_TYPEDEF:
1553                 case STORAGE_CLASS_AUTO:
1554                         break;
1555                 }
1556                 return EXPR_CLASS_VARIABLE;
1557         }
1558
1559         case EXPR_ERROR:
1560                 return EXPR_CLASS_ERROR;
1561
1562         default:
1563                 return EXPR_CLASS_VARIABLE;
1564         }
1565 }
1566
1567 expression_classification_t is_linker_constant(const expression_t *expression)
1568 {
1569         switch (expression->kind) {
1570         case EXPR_STRING_LITERAL:
1571         case EXPR_FUNCNAME:
1572         case EXPR_LABEL_ADDRESS:
1573                 return EXPR_CLASS_CONSTANT;
1574
1575         case EXPR_COMPOUND_LITERAL:
1576                 return is_constant_initializer(expression->compound_literal.initializer);
1577
1578         case EXPR_UNARY_TAKE_ADDRESS:
1579                 return is_object_with_linker_constant_address(expression->unary.value);
1580
1581         case EXPR_UNARY_DEREFERENCE: {
1582                 type_t *real_type
1583                         = revert_automatic_type_conversion(expression->unary.value);
1584                 /* dereferencing a function is a NOP */
1585                 if (is_type_function(real_type)) {
1586                         return is_linker_constant(expression->unary.value);
1587                 }
1588                 /* FALLTHROUGH */
1589         }
1590
1591         case EXPR_UNARY_CAST: {
1592                 type_t *dest = skip_typeref(expression->base.type);
1593                 if (!is_type_pointer(dest) && (
1594                                 dest->kind != TYPE_ATOMIC                                               ||
1595                                 !(get_atomic_type_flags(dest->atomic.akind) & ATOMIC_TYPE_FLAG_INTEGER) ||
1596                                 get_atomic_type_size(dest->atomic.akind) < get_type_size(type_void_ptr)
1597                     ))
1598                         return is_constant_expression(expression);
1599
1600                 return is_linker_constant(expression->unary.value);
1601         }
1602
1603         case EXPR_BINARY_ADD:
1604         case EXPR_BINARY_SUB: {
1605                 expression_t *const left  = expression->binary.left;
1606                 expression_t *const right = expression->binary.right;
1607                 type_t       *const ltype = skip_typeref(left->base.type);
1608                 type_t       *const rtype = skip_typeref(right->base.type);
1609
1610                 if (is_type_pointer(ltype)) {
1611                         expression_classification_t const l = is_linker_constant(left);
1612                         expression_classification_t const r = is_constant_expression(right);
1613                         return l < r ? l : r;
1614                 } else if (is_type_pointer(rtype)) {
1615                         expression_classification_t const l = is_constant_expression(left);
1616                         expression_classification_t const r = is_linker_constant(right);
1617                         return l < r ? l : r;
1618                 } else if (!is_type_valid(ltype) || !is_type_valid(rtype)) {
1619                         return EXPR_CLASS_ERROR;
1620                 } else {
1621                         return is_constant_expression(expression);
1622                 }
1623         }
1624
1625         case EXPR_REFERENCE: {
1626                 entity_t *entity = expression->reference.entity;
1627                 if (!is_declaration(entity))
1628                         return EXPR_CLASS_VARIABLE;
1629
1630                 type_t *type = skip_typeref(entity->declaration.type);
1631                 if (is_type_function(type))
1632                         return EXPR_CLASS_CONSTANT;
1633                 if (is_type_array(type)) {
1634                         return is_object_with_linker_constant_address(expression);
1635                 }
1636                 /* Prevent stray errors */
1637                 if (!is_type_valid(type))
1638                         return EXPR_CLASS_ERROR;
1639                 return EXPR_CLASS_VARIABLE;
1640         }
1641
1642         case EXPR_ARRAY_ACCESS: {
1643                 type_t *const type =
1644                         skip_typeref(revert_automatic_type_conversion(expression));
1645                 if (!is_type_array(type))
1646                         return EXPR_CLASS_VARIABLE;
1647                 return is_linker_constant(expression->array_access.array_ref);
1648         }
1649
1650         case EXPR_CONDITIONAL: {
1651                 expression_t *const c = expression->conditional.condition;
1652                 expression_classification_t const cclass = is_constant_expression(c);
1653                 if (cclass != EXPR_CLASS_CONSTANT)
1654                         return cclass;
1655
1656                 if (fold_constant_to_bool(c)) {
1657                         expression_t const *const t = expression->conditional.true_expression;
1658                         return is_linker_constant(t != NULL ? t : c);
1659                 } else {
1660                         return is_linker_constant(expression->conditional.false_expression);
1661                 }
1662         }
1663
1664         case EXPR_SELECT: {
1665                 entity_t *entity = expression->select.compound_entry;
1666                 if (!is_declaration(entity))
1667                         return EXPR_CLASS_VARIABLE;
1668                 type_t *type = skip_typeref(entity->declaration.type);
1669                 if (is_type_array(type)) {
1670                         /* arrays automatically convert to their address */
1671                         expression_t *compound  = expression->select.compound;
1672                         type_t       *base_type = skip_typeref(compound->base.type);
1673                         if (is_type_pointer(base_type)) {
1674                                 /* it's a -> */
1675                                 return is_linker_constant(compound);
1676                         } else {
1677                                 return is_object_with_linker_constant_address(compound);
1678                         }
1679                 }
1680                 return EXPR_CLASS_VARIABLE;
1681         }
1682
1683         default:
1684                 return is_constant_expression(expression);
1685         }
1686 }
1687
1688 /**
1689  * Check if the given expression is a call to a builtin function
1690  * returning a constant result.
1691  */
1692 static expression_classification_t is_builtin_const_call(const expression_t *expression)
1693 {
1694         expression_t *function = expression->call.function;
1695         if (function->kind != EXPR_REFERENCE)
1696                 return EXPR_CLASS_VARIABLE;
1697         reference_expression_t *ref = &function->reference;
1698         if (ref->entity->kind != ENTITY_FUNCTION)
1699                 return EXPR_CLASS_VARIABLE;
1700
1701         switch (ref->entity->function.btk) {
1702         case BUILTIN_INF:
1703         case BUILTIN_NAN:
1704                 return EXPR_CLASS_CONSTANT;
1705         default:
1706                 return EXPR_CLASS_VARIABLE;
1707         }
1708
1709 }
1710
1711 static expression_classification_t is_constant_pointer(const expression_t *expression)
1712 {
1713         expression_classification_t const expr_class = is_constant_expression(expression);
1714         if (expr_class != EXPR_CLASS_VARIABLE)
1715                 return expr_class;
1716
1717         switch (expression->kind) {
1718         case EXPR_UNARY_CAST:
1719                 return is_constant_pointer(expression->unary.value);
1720         default:
1721                 return EXPR_CLASS_VARIABLE;
1722         }
1723 }
1724
1725 static expression_classification_t is_object_with_constant_address(const expression_t *expression)
1726 {
1727         switch (expression->kind) {
1728         case EXPR_SELECT: {
1729                 expression_t *compound      = expression->select.compound;
1730                 type_t       *compound_type = compound->base.type;
1731                 compound_type = skip_typeref(compound_type);
1732                 if (is_type_pointer(compound_type)) {
1733                         return is_constant_pointer(compound);
1734                 } else {
1735                         return is_object_with_constant_address(compound);
1736                 }
1737         }
1738
1739         case EXPR_ARRAY_ACCESS: {
1740                 array_access_expression_t const* const array_access =
1741                         &expression->array_access;
1742                 expression_classification_t const idx_class = is_constant_expression(array_access->index);
1743                 if (idx_class != EXPR_CLASS_CONSTANT)
1744                         return idx_class;
1745                 expression_classification_t const ref_addr = is_object_with_constant_address(array_access->array_ref);
1746                 expression_classification_t const ref_ptr  = is_constant_pointer(array_access->array_ref);
1747                 return ref_addr > ref_ptr ? ref_addr : ref_ptr;
1748         }
1749
1750         case EXPR_UNARY_DEREFERENCE:
1751                 return is_constant_pointer(expression->unary.value);
1752
1753         case EXPR_ERROR:
1754                 return EXPR_CLASS_ERROR;
1755
1756         default:
1757                 return EXPR_CLASS_VARIABLE;
1758         }
1759 }
1760
1761 expression_classification_t is_constant_expression(const expression_t *expression)
1762 {
1763         switch (expression->kind) {
1764         case EXPR_LITERAL_CHARACTER:
1765         case EXPR_BUILTIN_TYPES_COMPATIBLE_P:
1766         case EXPR_ENUM_CONSTANT:
1767         case EXPR_LITERAL_BOOLEAN:
1768         case EXPR_LITERAL_MS_NOOP:
1769                 return EXPR_CLASS_CONSTANT;
1770
1771         {
1772                 type_t *type;
1773         case EXPR_ALIGNOF:
1774                 type = skip_typeref(expression->typeprop.type);
1775                 goto check_type;
1776
1777         case EXPR_CLASSIFY_TYPE:
1778                 type = skip_typeref(expression->classify_type.type_expression->base.type);
1779                 goto check_type;
1780
1781         case EXPR_LITERAL_INTEGER:
1782         case EXPR_LITERAL_FLOATINGPOINT:
1783                 type = skip_typeref(expression->base.type);
1784                 goto check_type;
1785
1786         case EXPR_OFFSETOF:
1787                 type = skip_typeref(expression->offsetofe.type);
1788                 goto check_type;
1789
1790         case EXPR_SIZEOF:
1791                 type = skip_typeref(expression->typeprop.type);
1792                 if (is_type_array(type) && type->array.is_vla)
1793                         return EXPR_CLASS_VARIABLE;
1794                 goto check_type;
1795
1796 check_type:
1797                 return is_type_valid(type) ? EXPR_CLASS_CONSTANT : EXPR_CLASS_ERROR;
1798         }
1799
1800         case EXPR_BUILTIN_CONSTANT_P: {
1801                 expression_classification_t const c = is_constant_expression(expression->builtin_constant.value);
1802                 return c != EXPR_CLASS_ERROR ? EXPR_CLASS_CONSTANT : EXPR_CLASS_ERROR;
1803         }
1804
1805         case EXPR_STRING_LITERAL:
1806         case EXPR_FUNCNAME:
1807         case EXPR_LABEL_ADDRESS:
1808         case EXPR_SELECT:
1809         case EXPR_VA_START:
1810         case EXPR_VA_ARG:
1811         case EXPR_VA_COPY:
1812         case EXPR_STATEMENT:
1813         case EXPR_UNARY_POSTFIX_INCREMENT:
1814         case EXPR_UNARY_POSTFIX_DECREMENT:
1815         case EXPR_UNARY_PREFIX_INCREMENT:
1816         case EXPR_UNARY_PREFIX_DECREMENT:
1817         case EXPR_UNARY_ASSUME: /* has VOID type */
1818         case EXPR_UNARY_DEREFERENCE:
1819         case EXPR_UNARY_DELETE:
1820         case EXPR_UNARY_DELETE_ARRAY:
1821         case EXPR_UNARY_THROW:
1822         case EXPR_BINARY_ASSIGN:
1823         case EXPR_BINARY_MUL_ASSIGN:
1824         case EXPR_BINARY_DIV_ASSIGN:
1825         case EXPR_BINARY_MOD_ASSIGN:
1826         case EXPR_BINARY_ADD_ASSIGN:
1827         case EXPR_BINARY_SUB_ASSIGN:
1828         case EXPR_BINARY_SHIFTLEFT_ASSIGN:
1829         case EXPR_BINARY_SHIFTRIGHT_ASSIGN:
1830         case EXPR_BINARY_BITWISE_AND_ASSIGN:
1831         case EXPR_BINARY_BITWISE_XOR_ASSIGN:
1832         case EXPR_BINARY_BITWISE_OR_ASSIGN:
1833         case EXPR_BINARY_COMMA:
1834         case EXPR_ARRAY_ACCESS:
1835                 return EXPR_CLASS_VARIABLE;
1836
1837         case EXPR_REFERENCE: {
1838                 type_t *const type = skip_typeref(expression->base.type);
1839                 return is_type_valid(type) ? EXPR_CLASS_VARIABLE : EXPR_CLASS_ERROR;
1840         }
1841
1842         case EXPR_UNARY_TAKE_ADDRESS:
1843                 return is_object_with_constant_address(expression->unary.value);
1844
1845         case EXPR_CALL:
1846                 return is_builtin_const_call(expression);
1847
1848         case EXPR_UNARY_NEGATE:
1849         case EXPR_UNARY_PLUS:
1850         case EXPR_UNARY_BITWISE_NEGATE:
1851         case EXPR_UNARY_NOT:
1852                 return is_constant_expression(expression->unary.value);
1853
1854         case EXPR_UNARY_CAST: {
1855                 type_t *const type = skip_typeref(expression->base.type);
1856                 if (is_type_scalar(type))
1857                         return is_constant_expression(expression->unary.value);
1858                 if (!is_type_valid(type))
1859                         return EXPR_CLASS_ERROR;
1860                 return EXPR_CLASS_VARIABLE;
1861         }
1862
1863         case EXPR_BINARY_ADD:
1864         case EXPR_BINARY_SUB:
1865         case EXPR_BINARY_MUL:
1866         case EXPR_BINARY_DIV:
1867         case EXPR_BINARY_MOD:
1868         case EXPR_BINARY_EQUAL:
1869         case EXPR_BINARY_NOTEQUAL:
1870         case EXPR_BINARY_LESS:
1871         case EXPR_BINARY_LESSEQUAL:
1872         case EXPR_BINARY_GREATER:
1873         case EXPR_BINARY_GREATEREQUAL:
1874         case EXPR_BINARY_BITWISE_AND:
1875         case EXPR_BINARY_BITWISE_OR:
1876         case EXPR_BINARY_BITWISE_XOR:
1877         case EXPR_BINARY_SHIFTLEFT:
1878         case EXPR_BINARY_SHIFTRIGHT:
1879         case EXPR_BINARY_ISGREATER:
1880         case EXPR_BINARY_ISGREATEREQUAL:
1881         case EXPR_BINARY_ISLESS:
1882         case EXPR_BINARY_ISLESSEQUAL:
1883         case EXPR_BINARY_ISLESSGREATER:
1884         case EXPR_BINARY_ISUNORDERED: {
1885                 expression_classification_t const l = is_constant_expression(expression->binary.left);
1886                 expression_classification_t const r = is_constant_expression(expression->binary.right);
1887                 return l < r ? l : r;
1888         }
1889
1890         case EXPR_BINARY_LOGICAL_AND: {
1891                 expression_t const         *const left   = expression->binary.left;
1892                 expression_classification_t const lclass = is_constant_expression(left);
1893                 if (lclass != EXPR_CLASS_CONSTANT)
1894                         return lclass;
1895                 if (!fold_constant_to_bool(left))
1896                         return EXPR_CLASS_CONSTANT;
1897                 return is_constant_expression(expression->binary.right);
1898         }
1899
1900         case EXPR_BINARY_LOGICAL_OR: {
1901                 expression_t const         *const left   = expression->binary.left;
1902                 expression_classification_t const lclass = is_constant_expression(left);
1903                 if (lclass != EXPR_CLASS_CONSTANT)
1904                         return lclass;
1905                 if (fold_constant_to_bool(left))
1906                         return EXPR_CLASS_CONSTANT;
1907                 return is_constant_expression(expression->binary.right);
1908         }
1909
1910         case EXPR_COMPOUND_LITERAL:
1911                 return is_constant_initializer(expression->compound_literal.initializer);
1912
1913         case EXPR_CONDITIONAL: {
1914                 expression_t               *const condition = expression->conditional.condition;
1915                 expression_classification_t const cclass    = is_constant_expression(condition);
1916                 if (cclass != EXPR_CLASS_CONSTANT)
1917                         return cclass;
1918
1919                 if (fold_constant_to_bool(condition)) {
1920                         expression_t const *const t = expression->conditional.true_expression;
1921                         return t == NULL ? EXPR_CLASS_CONSTANT : is_constant_expression(t);
1922                 } else {
1923                         return is_constant_expression(expression->conditional.false_expression);
1924                 }
1925         }
1926
1927         case EXPR_ERROR:
1928                 return EXPR_CLASS_ERROR;
1929         }
1930         panic("invalid expression found (is constant expression)");
1931 }
1932
1933 void init_ast(void)
1934 {
1935         obstack_init(&ast_obstack);
1936 }
1937
1938 void exit_ast(void)
1939 {
1940         obstack_free(&ast_obstack, NULL);
1941 }