nsz Git - cparser/blob - ast.c

   1 /*
   2  * This file is part of cparser.
   3  * Copyright (C) 2007-2008 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
  26 #include <assert.h>
  27 #include <stdio.h>
  28 #include <stdlib.h>
  29 #include <ctype.h>
  30
  31 #include "adt/error.h"
  32
  33 struct obstack ast_obstack;
  34
  35 static FILE *out;
  36 static int   indent;
  37
  38 /** If set, implicit casts are printed. */
  39 bool print_implicit_casts = false;
  40
  41 /** If set parenthesis are printed to indicate operator precedence. */
  42 bool print_parenthesis = false;
  43
  44 static void print_statement(const statement_t *statement);
  45 static void print_expression_prec(const expression_t *expression, unsigned prec);
  46
  47 void change_indent(int delta)
  48 {
  49         indent += delta;
  50         assert(indent >= 0);
  51 }
  52
  53 void print_indent(void)
  54 {
  55         for(int i = 0; i < indent; ++i)
  56                 fprintf(out, "\t");
  57 }
  58
  59 enum precedence_t {
  60         PREC_BOTTOM  =  0,
  61         PREC_COMMA   =  2, /* ,                                    left to right */
  62         PREC_ASSIGN  =  4, /* = += -= *= /= %= <<= >>= &= ^= |=    right to left */
  63         PREC_COND    =  6, /* ?:                                   right to left */
  64         PREC_LOG_OR  =  8, /* ||                                   left to right */
  65         PREC_LOG_AND = 10, /* &&                                   left to right */
  66         PREC_BIT_OR  = 12, /* |                                    left to right */
  67         PREC_BIT_XOR = 14, /* ^                                    left to right */
  68         PREC_BIT_AND = 16, /* &                                    left to right */
  69         PREC_EQ      = 18, /* == !=                                left to right */
  70         PREC_CMP     = 20, /* < <= > >=                            left to right */
  71         PREC_SHF     = 22, /* << >>                                left to right */
  72         PREC_PLUS    = 24, /* + -                                  left to right */
  73         PREC_MUL     = 26, /* * / %                                left to right */
  74         PREC_UNARY   = 28, /* ! ~ ++ -- + - (type) * & sizeof      right to left */
  75         PREC_ACCESS  = 30, /* () [] -> .                           left to right */
  76         PREC_PRIM    = 32, /* primary */
  77         PREC_TOP     = 34
  78 };
  79
  80 /**
  81  * Returns 1 if a given precedence level has right-to-left
  82  * associativity, else -1.
  83  *
  84  * @param precedence   the operator precedence
  85  */
  86 static int right_to_left(unsigned precedence) {
  87         return (precedence == PREC_ASSIGN || precedence == PREC_COND ||
  88                 precedence == PREC_UNARY) ? 1 : -1;
  89 }
  90
  91 /**
  92  * Return the precedence of an expression given by its kind.
  93  *
  94  * @param kind   the expression kind
  95  */
  96 static unsigned get_expression_precedence(expression_kind_t kind)
  97 {
  98         static const unsigned prec[] = {
  99                 [EXPR_UNKNOWN]                   = PREC_PRIM,
 100                 [EXPR_INVALID]                   = PREC_PRIM,
 101                 [EXPR_REFERENCE]                 = PREC_PRIM,
 102                 [EXPR_CHARACTER_CONSTANT]        = PREC_PRIM,
 103                 [EXPR_WIDE_CHARACTER_CONSTANT]   = PREC_PRIM,
 104                 [EXPR_CONST]                     = PREC_PRIM,
 105                 [EXPR_STRING_LITERAL]            = PREC_PRIM,
 106                 [EXPR_WIDE_STRING_LITERAL]       = PREC_PRIM,
 107                 [EXPR_COMPOUND_LITERAL]          = PREC_UNARY,
 108                 [EXPR_CALL]                      = PREC_PRIM,
 109                 [EXPR_CONDITIONAL]               = PREC_COND,
 110                 [EXPR_SELECT]                    = PREC_ACCESS,
 111                 [EXPR_ARRAY_ACCESS]              = PREC_ACCESS,
 112                 [EXPR_SIZEOF]                    = PREC_UNARY,
 113                 [EXPR_CLASSIFY_TYPE]             = PREC_UNARY,
 114                 [EXPR_ALIGNOF]                   = PREC_UNARY,
 115
 116                 [EXPR_FUNCTION]                  = PREC_PRIM,
 117                 [EXPR_PRETTY_FUNCTION]           = PREC_PRIM,
 118                 [EXPR_BUILTIN_SYMBOL]            = PREC_PRIM,
 119                 [EXPR_BUILTIN_CONSTANT_P]        = PREC_PRIM,
 120                 [EXPR_BUILTIN_PREFETCH]          = PREC_PRIM,
 121                 [EXPR_OFFSETOF]                  = PREC_PRIM,
 122                 [EXPR_VA_START]                  = PREC_PRIM,
 123                 [EXPR_VA_ARG]                    = PREC_PRIM,
 124                 [EXPR_STATEMENT]                 = PREC_ACCESS,
 125
 126                 [EXPR_UNARY_NEGATE]              = PREC_UNARY,
 127                 [EXPR_UNARY_PLUS]                = PREC_UNARY,
 128                 [EXPR_UNARY_BITWISE_NEGATE]      = PREC_UNARY,
 129                 [EXPR_UNARY_NOT]                 = PREC_UNARY,
 130                 [EXPR_UNARY_DEREFERENCE]         = PREC_UNARY,
 131                 [EXPR_UNARY_TAKE_ADDRESS]        = PREC_UNARY,
 132                 [EXPR_UNARY_POSTFIX_INCREMENT]   = PREC_UNARY,
 133                 [EXPR_UNARY_POSTFIX_DECREMENT]   = PREC_UNARY,
 134                 [EXPR_UNARY_PREFIX_INCREMENT]    = PREC_UNARY,
 135                 [EXPR_UNARY_PREFIX_DECREMENT]    = PREC_UNARY,
 136                 [EXPR_UNARY_CAST]                = PREC_UNARY,
 137                 [EXPR_UNARY_CAST_IMPLICIT]       = PREC_UNARY,
 138                 [EXPR_UNARY_ASSUME]              = PREC_PRIM,
 139                 [EXPR_UNARY_BITFIELD_EXTRACT]    = PREC_ACCESS,
 140
 141                 [EXPR_BINARY_ADD]                = PREC_PLUS,
 142                 [EXPR_BINARY_SUB]                = PREC_PLUS,
 143                 [EXPR_BINARY_MUL]                = PREC_MUL,
 144                 [EXPR_BINARY_DIV]                = PREC_MUL,
 145                 [EXPR_BINARY_MOD]                = PREC_MUL,
 146                 [EXPR_BINARY_EQUAL]              = PREC_EQ,
 147                 [EXPR_BINARY_NOTEQUAL]           = PREC_EQ,
 148                 [EXPR_BINARY_LESS]               = PREC_CMP,
 149                 [EXPR_BINARY_LESSEQUAL]          = PREC_CMP,
 150                 [EXPR_BINARY_GREATER]            = PREC_CMP,
 151                 [EXPR_BINARY_GREATEREQUAL]       = PREC_CMP,
 152                 [EXPR_BINARY_BITWISE_AND]        = PREC_BIT_AND,
 153                 [EXPR_BINARY_BITWISE_OR]         = PREC_BIT_OR,
 154                 [EXPR_BINARY_BITWISE_XOR]        = PREC_BIT_XOR,
 155                 [EXPR_BINARY_LOGICAL_AND]        = PREC_LOG_AND,
 156                 [EXPR_BINARY_LOGICAL_OR]         = PREC_LOG_OR,
 157                 [EXPR_BINARY_SHIFTLEFT]          = PREC_SHF,
 158                 [EXPR_BINARY_SHIFTRIGHT]         = PREC_SHF,
 159                 [EXPR_BINARY_ASSIGN]             = PREC_ASSIGN,
 160                 [EXPR_BINARY_MUL_ASSIGN]         = PREC_ASSIGN,
 161                 [EXPR_BINARY_DIV_ASSIGN]         = PREC_ASSIGN,
 162                 [EXPR_BINARY_MOD_ASSIGN]         = PREC_ASSIGN,
 163                 [EXPR_BINARY_ADD_ASSIGN]         = PREC_ASSIGN,
 164                 [EXPR_BINARY_SUB_ASSIGN]         = PREC_ASSIGN,
 165                 [EXPR_BINARY_SHIFTLEFT_ASSIGN]   = PREC_ASSIGN,
 166                 [EXPR_BINARY_SHIFTRIGHT_ASSIGN]  = PREC_ASSIGN,
 167                 [EXPR_BINARY_BITWISE_AND_ASSIGN] = PREC_ASSIGN,
 168                 [EXPR_BINARY_BITWISE_XOR_ASSIGN] = PREC_ASSIGN,
 169                 [EXPR_BINARY_BITWISE_OR_ASSIGN]  = PREC_ASSIGN,
 170                 [EXPR_BINARY_COMMA]              = PREC_COMMA,
 171
 172                 [EXPR_BINARY_BUILTIN_EXPECT]     = PREC_PRIM,
 173                 [EXPR_BINARY_ISGREATER]          = PREC_PRIM,
 174                 [EXPR_BINARY_ISGREATEREQUAL]     = PREC_PRIM,
 175                 [EXPR_BINARY_ISLESS]             = PREC_PRIM,
 176                 [EXPR_BINARY_ISLESSEQUAL]        = PREC_PRIM,
 177                 [EXPR_BINARY_ISLESSGREATER]      = PREC_PRIM,
 178                 [EXPR_BINARY_ISUNORDERED]        = PREC_PRIM
 179         };
 180         assert((unsigned)kind < (sizeof(prec)/sizeof(prec[0])));
 181         unsigned res = prec[kind];
 182
 183         assert(res != PREC_BOTTOM);
 184         return res;
 185 }
 186
 187 /**
 188  * Print a constant expression.
 189  *
 190  * @param cnst  the constant expression
 191  */
 192 static void print_const(const const_expression_t *cnst)
 193 {
 194         if(cnst->base.type == NULL)
 195                 return;
 196
 197         const type_t *const type = skip_typeref(cnst->base.type);
 198
 199         if (is_type_integer(type)) {
 200                 fprintf(out, "%lld", cnst->v.int_value);
 201         } else if (is_type_float(type)) {
 202                 fprintf(out, "%Lf", cnst->v.float_value);
 203         } else {
 204                 panic("unknown constant");
 205         }
 206 }
 207
 208 /**
 209  * Print a quoted string constant.
 210  *
 211  * @param string  the string constant
 212  * @param border  the border char
 213  */
 214 static void print_quoted_string(const string_t *const string, char border)
 215 {
 216         fputc(border, out);
 217         const char *end = string->begin + string->size - 1;
 218         for (const char *c = string->begin; c != end; ++c) {
 219                 if (*c == border) {
 220                         fputc('\\', out);
 221                 }
 222                 switch(*c) {
 223                 case '\\':  fputs("\\\\", out); break;
 224                 case '\a':  fputs("\\a", out); break;
 225                 case '\b':  fputs("\\b", out); break;
 226                 case '\f':  fputs("\\f", out); break;
 227                 case '\n':  fputs("\\n", out); break;
 228                 case '\r':  fputs("\\r", out); break;
 229                 case '\t':  fputs("\\t", out); break;
 230                 case '\v':  fputs("\\v", out); break;
 231                 case '\?':  fputs("\\?", out); break;
 232                 default:
 233                         if(!isprint(*c)) {
 234                                 fprintf(out, "\\%03o", *c);
 235                                 break;
 236                         }
 237                         fputc(*c, out);
 238                         break;
 239                 }
 240         }
 241         fputc(border, out);
 242 }
 243
 244 /**
 245  * Prints a wide string literal expression.
 246  *
 247  * @param wstr  the wide string literal expression
 248  */
 249 static void print_quoted_wide_string(const wide_string_t *const wstr,
 250                                      char border)
 251 {
 252         fputc('L', out);
 253         fputc(border, out);
 254         for (const wchar_rep_t *c = wstr->begin, *end = wstr->begin + wstr->size-1;
 255              c != end; ++c) {
 256                 switch (*c) {
 257                         case L'\"':  fputs("\\\"", out); break;
 258                         case L'\\':  fputs("\\\\", out); break;
 259                         case L'\a':  fputs("\\a",  out); break;
 260                         case L'\b':  fputs("\\b",  out); break;
 261                         case L'\f':  fputs("\\f",  out); break;
 262                         case L'\n':  fputs("\\n",  out); break;
 263                         case L'\r':  fputs("\\r",  out); break;
 264                         case L'\t':  fputs("\\t",  out); break;
 265                         case L'\v':  fputs("\\v",  out); break;
 266                         case L'\?':  fputs("\\?",  out); break;
 267                         default: {
 268                                 const unsigned tc = *c;
 269                                 if (tc < 0x80U) {
 270                                         if (!isprint(*c))  {
 271                                                 fprintf(out, "\\%03o", (char)*c);
 272                                         } else {
 273                                                 fputc(*c, out);
 274                                         }
 275                                 } else if (tc < 0x800) {
 276                                         fputc(0xC0 | (tc >> 6),   out);
 277                                         fputc(0x80 | (tc & 0x3F), out);
 278                                 } else if (tc < 0x10000) {
 279                                         fputc(0xE0 | ( tc >> 12),         out);
 280                                         fputc(0x80 | ((tc >>  6) & 0x3F), out);
 281                                         fputc(0x80 | ( tc        & 0x3F), out);
 282                                 } else {
 283                                         fputc(0xF0 | ( tc >> 18),         out);
 284                                         fputc(0x80 | ((tc >> 12) & 0x3F), out);
 285                                         fputc(0x80 | ((tc >>  6) & 0x3F), out);
 286                                         fputc(0x80 | ( tc        & 0x3F), out);
 287                                 }
 288                         }
 289                 }
 290         }
 291         fputc(border, out);
 292 }
 293
 294 /**
 295  * Print a constant character expression.
 296  *
 297  * @param cnst  the constant character expression
 298  */
 299 static void print_character_constant(const const_expression_t *cnst)
 300 {
 301         print_quoted_string(&cnst->v.character, '\'');
 302 }
 303
 304 static void print_wide_character_constant(const const_expression_t *cnst)
 305 {
 306         print_quoted_wide_string(&cnst->v.wide_character, '\'');
 307 }
 308
 309 /**
 310  * Prints a string literal expression.
 311  *
 312  * @param string_literal  the string literal expression
 313  */
 314 static void print_string_literal(
 315                 const string_literal_expression_t *string_literal)
 316 {
 317         print_quoted_string(&string_literal->value, '"');
 318 }
 319
 320 static void print_wide_string_literal(
 321         const wide_string_literal_expression_t *const wstr)
 322 {
 323         print_quoted_wide_string(&wstr->value, '"');
 324 }
 325
 326 static void print_compound_literal(
 327                 const compound_literal_expression_t *expression)
 328 {
 329         fputc('(', out);
 330         print_type(expression->type);
 331         fputs(") ", out);
 332         print_initializer(expression->initializer);
 333 }
 334
 335 /**
 336  * Prints a call expression.
 337  *
 338  * @param call  the call expression
 339  */
 340 static void print_call_expression(const call_expression_t *call)
 341 {
 342         unsigned prec = get_expression_precedence(call->base.kind);
 343         print_expression_prec(call->function, prec);
 344         fprintf(out, "(");
 345         call_argument_t *argument = call->arguments;
 346         int              first    = 1;
 347         while(argument != NULL) {
 348                 if(!first) {
 349                         fprintf(out, ", ");
 350                 } else {
 351                         first = 0;
 352                 }
 353                 print_expression_prec(argument->expression, PREC_COMMA + 1);
 354
 355                 argument = argument->next;
 356         }
 357         fprintf(out, ")");
 358 }
 359
 360 /**
 361  * Prints a binary expression.
 362  *
 363  * @param binexpr   the binary expression
 364  */
 365 static void print_binary_expression(const binary_expression_t *binexpr)
 366 {
 367         unsigned prec = get_expression_precedence(binexpr->base.kind);
 368         int      r2l  = right_to_left(prec);
 369
 370         if(binexpr->base.kind == EXPR_BINARY_BUILTIN_EXPECT) {
 371                 fputs("__builtin_expect(", out);
 372                 print_expression_prec(binexpr->left, prec);
 373                 fputs(", ", out);
 374                 print_expression_prec(binexpr->right, prec);
 375                 fputc(')', out);
 376                 return;
 377         }
 378
 379         print_expression_prec(binexpr->left, prec + r2l);
 380         if (binexpr->base.kind != EXPR_BINARY_COMMA) {
 381                 fputc(' ', out);
 382         }
 383         switch (binexpr->base.kind) {
 384         case EXPR_BINARY_COMMA:              fputs(",", out);     break;
 385         case EXPR_BINARY_ASSIGN:             fputs("=", out);     break;
 386         case EXPR_BINARY_ADD:                fputs("+", out);     break;
 387         case EXPR_BINARY_SUB:                fputs("-", out);     break;
 388         case EXPR_BINARY_MUL:                fputs("*", out);     break;
 389         case EXPR_BINARY_MOD:                fputs("%", out);     break;
 390         case EXPR_BINARY_DIV:                fputs("/", out);     break;
 391         case EXPR_BINARY_BITWISE_OR:         fputs("|", out);     break;
 392         case EXPR_BINARY_BITWISE_AND:        fputs("&", out);     break;
 393         case EXPR_BINARY_BITWISE_XOR:        fputs("^", out);     break;
 394         case EXPR_BINARY_LOGICAL_OR:         fputs("||", out);    break;
 395         case EXPR_BINARY_LOGICAL_AND:        fputs("&&", out);    break;
 396         case EXPR_BINARY_NOTEQUAL:           fputs("!=", out);    break;
 397         case EXPR_BINARY_EQUAL:              fputs("==", out);    break;
 398         case EXPR_BINARY_LESS:               fputs("<", out);     break;
 399         case EXPR_BINARY_LESSEQUAL:          fputs("<=", out);    break;
 400         case EXPR_BINARY_GREATER:            fputs(">", out);     break;
 401         case EXPR_BINARY_GREATEREQUAL:       fputs(">=", out);    break;
 402         case EXPR_BINARY_SHIFTLEFT:          fputs("<<", out);    break;
 403         case EXPR_BINARY_SHIFTRIGHT:         fputs(">>", out);    break;
 404
 405         case EXPR_BINARY_ADD_ASSIGN:         fputs("+=", out);    break;
 406         case EXPR_BINARY_SUB_ASSIGN:         fputs("-=", out);    break;
 407         case EXPR_BINARY_MUL_ASSIGN:         fputs("*=", out);    break;
 408         case EXPR_BINARY_MOD_ASSIGN:         fputs("%=", out);    break;
 409         case EXPR_BINARY_DIV_ASSIGN:         fputs("/=", out);    break;
 410         case EXPR_BINARY_BITWISE_OR_ASSIGN:  fputs("|=", out);    break;
 411         case EXPR_BINARY_BITWISE_AND_ASSIGN: fputs("&=", out);    break;
 412         case EXPR_BINARY_BITWISE_XOR_ASSIGN: fputs("^=", out);    break;
 413         case EXPR_BINARY_SHIFTLEFT_ASSIGN:   fputs("<<=", out);   break;
 414         case EXPR_BINARY_SHIFTRIGHT_ASSIGN:  fputs(">>=", out);   break;
 415         default: panic("invalid binexpression found");
 416         }
 417         fputc(' ', out);
 418         print_expression_prec(binexpr->right, prec - r2l);
 419 }
 420
 421 /**
 422  * Prints an unary expression.
 423  *
 424  * @param unexpr   the unary expression
 425  */
 426 static void print_unary_expression(const unary_expression_t *unexpr)
 427 {
 428         unsigned prec = get_expression_precedence(unexpr->base.kind);
 429         switch(unexpr->base.kind) {
 430         case EXPR_UNARY_NEGATE:           fputs("-", out);  break;
 431         case EXPR_UNARY_PLUS:             fputs("+", out);  break;
 432         case EXPR_UNARY_NOT:              fputs("!", out);  break;
 433         case EXPR_UNARY_BITWISE_NEGATE:   fputs("~", out);  break;
 434         case EXPR_UNARY_PREFIX_INCREMENT: fputs("++", out); break;
 435         case EXPR_UNARY_PREFIX_DECREMENT: fputs("--", out); break;
 436         case EXPR_UNARY_DEREFERENCE:      fputs("*", out);  break;
 437         case EXPR_UNARY_TAKE_ADDRESS:     fputs("&", out);  break;
 438
 439         case EXPR_UNARY_BITFIELD_EXTRACT:
 440                 print_expression_prec(unexpr->value, prec);
 441                 return;
 442
 443         case EXPR_UNARY_POSTFIX_INCREMENT:
 444                 print_expression_prec(unexpr->value, prec);
 445                 fputs("++", out);
 446                 return;
 447         case EXPR_UNARY_POSTFIX_DECREMENT:
 448                 print_expression_prec(unexpr->value, prec);
 449                 fputs("--", out);
 450                 return;
 451         case EXPR_UNARY_CAST_IMPLICIT:
 452                 if(!print_implicit_casts) {
 453                         print_expression_prec(unexpr->value, prec);
 454                         return;
 455                 }
 456                 /* fallthrough */
 457         case EXPR_UNARY_CAST:
 458                 fputc('(', out);
 459                 print_type(unexpr->base.type);
 460                 fputc(')', out);
 461                 break;
 462         case EXPR_UNARY_ASSUME:
 463                 fputs("__assume(", out);
 464                 print_expression_prec(unexpr->value, PREC_COMMA + 1);
 465                 fputc(')', out);
 466                 return;
 467         default:
 468                 panic("invalid unary expression found");
 469         }
 470         print_expression_prec(unexpr->value, prec);
 471 }
 472
 473 /**
 474  * Prints a reference expression.
 475  *
 476  * @param ref   the reference expression
 477  */
 478 static void print_reference_expression(const reference_expression_t *ref)
 479 {
 480         fprintf(out, "%s", ref->declaration->symbol->string);
 481 }
 482
 483 /**
 484  * Prints an array expression.
 485  *
 486  * @param expression   the array expression
 487  */
 488 static void print_array_expression(const array_access_expression_t *expression)
 489 {
 490         unsigned prec = get_expression_precedence(expression->base.kind);
 491         if(!expression->flipped) {
 492                 print_expression_prec(expression->array_ref, prec);
 493                 fputc('[', out);
 494                 print_expression_prec(expression->index, prec);
 495                 fputc(']', out);
 496         } else {
 497                 print_expression_prec(expression->index, prec);
 498                 fputc('[', out);
 499                 print_expression_prec(expression->array_ref, prec);
 500                 fputc(']', out);
 501         }
 502 }
 503
 504 /**
 505  * Prints a typeproperty expression (sizeof or __alignof__).
 506  *
 507  * @param expression   the type property expression
 508  */
 509 static void print_typeprop_expression(const typeprop_expression_t *expression)
 510 {
 511         if (expression->base.kind == EXPR_SIZEOF) {
 512                 fputs("sizeof", out);
 513         } else {
 514                 assert(expression->base.kind == EXPR_ALIGNOF);
 515                 fputs("__alignof__", out);
 516         }
 517         if(expression->tp_expression != NULL) {
 518                 /* always print the '()' here, sizeof x is right but unusual */
 519                 fputc('(', out);
 520                 print_expression_prec(expression->tp_expression, PREC_ACCESS);
 521                 fputc(')', out);
 522         } else {
 523                 fputc('(', out);
 524                 print_type(expression->type);
 525                 fputc(')', out);
 526         }
 527 }
 528
 529 /**
 530  * Prints an builtin symbol.
 531  *
 532  * @param expression   the builtin symbol expression
 533  */
 534 static void print_builtin_symbol(const builtin_symbol_expression_t *expression)
 535 {
 536         fputs(expression->symbol->string, out);
 537 }
 538
 539 /**
 540  * Prints a builtin constant expression.
 541  *
 542  * @param expression   the builtin constant expression
 543  */
 544 static void print_builtin_constant(const builtin_constant_expression_t *expression)
 545 {
 546         fputs("__builtin_constant_p(", out);
 547         print_expression_prec(expression->value, PREC_COMMA + 1);
 548         fputc(')', out);
 549 }
 550
 551 /**
 552  * Prints a builtin prefetch expression.
 553  *
 554  * @param expression   the builtin prefetch expression
 555  */
 556 static void print_builtin_prefetch(const builtin_prefetch_expression_t *expression)
 557 {
 558         fputs("__builtin_prefetch(", out);
 559         print_expression_prec(expression->adr, PREC_COMMA + 1);
 560         if (expression->rw) {
 561                 fputc(',', out);
 562                 print_expression_prec(expression->rw, PREC_COMMA + 1);
 563         }
 564         if (expression->locality) {
 565                 fputc(',', out);
 566                 print_expression_prec(expression->locality, PREC_COMMA + 1);
 567         }
 568         fputc(')', out);
 569 }
 570
 571 /**
 572  * Prints a conditional expression.
 573  *
 574  * @param expression   the conditional expression
 575  */
 576 static void print_conditional(const conditional_expression_t *expression)
 577 {
 578         unsigned prec = get_expression_precedence(expression->base.kind);
 579         fputs("(", out);
 580         print_expression_prec(expression->condition, prec);
 581         fputs(" ? ", out);
 582         print_expression_prec(expression->true_expression, prec);
 583         fputs(" : ", out);
 584         print_expression_prec(expression->false_expression, prec);
 585         fputs(")", out);
 586 }
 587
 588 /**
 589  * Prints a va_start expression.
 590  *
 591  * @param expression   the va_start expression
 592  */
 593 static void print_va_start(const va_start_expression_t *const expression)
 594 {
 595         fputs("__builtin_va_start(", out);
 596         print_expression_prec(expression->ap, PREC_COMMA + 1);
 597         fputs(", ", out);
 598         fputs(expression->parameter->symbol->string, out);
 599         fputs(")", out);
 600 }
 601
 602 /**
 603  * Prints a va_arg expression.
 604  *
 605  * @param expression   the va_arg expression
 606  */
 607 static void print_va_arg(const va_arg_expression_t *expression)
 608 {
 609         fputs("__builtin_va_arg(", out);
 610         print_expression_prec(expression->ap, PREC_COMMA + 1);
 611         fputs(", ", out);
 612         print_type(expression->base.type);
 613         fputs(")", out);
 614 }
 615
 616 /**
 617  * Prints a select expression (. or ->).
 618  *
 619  * @param expression   the select expression
 620  */
 621 static void print_select(const select_expression_t *expression)
 622 {
 623         unsigned prec = get_expression_precedence(expression->base.kind);
 624         print_expression_prec(expression->compound, prec);
 625         if(is_type_pointer(expression->compound->base.type)) {
 626                 fputs("->", out);
 627         } else {
 628                 fputc('.', out);
 629         }
 630         fputs(expression->symbol->string, out);
 631 }
 632
 633 /**
 634  * Prints a type classify expression.
 635  *
 636  * @param expr   the type classify expression
 637  */
 638 static void print_classify_type_expression(
 639         const classify_type_expression_t *const expr)
 640 {
 641         fputs("__builtin_classify_type(", out);
 642         print_expression_prec(expr->type_expression, PREC_COMMA + 1);
 643         fputc(')', out);
 644 }
 645
 646 /**
 647  * Prints a designator.
 648  *
 649  * @param designator  the designator
 650  */
 651 static void print_designator(const designator_t *designator)
 652 {
 653         for ( ; designator != NULL; designator = designator->next) {
 654                 if (designator->symbol == NULL) {
 655                         fputc('[', out);
 656                         print_expression_prec(designator->array_index, PREC_ACCESS);
 657                         fputc(']', out);
 658                 } else {
 659                         fputc('.', out);
 660                         fputs(designator->symbol->string, out);
 661                 }
 662         }
 663 }
 664
 665 /**
 666  * Prints an offsetof expression.
 667  *
 668  * @param expression   the offset expression
 669  */
 670 static void print_offsetof_expression(const offsetof_expression_t *expression)
 671 {
 672         fputs("__builtin_offsetof", out);
 673         fputc('(', out);
 674         print_type(expression->type);
 675         fputc(',', out);
 676         print_designator(expression->designator);
 677         fputc(')', out);
 678 }
 679
 680 /**
 681  * Prints a statement expression.
 682  *
 683  * @param expression   the statement expression
 684  */
 685 static void print_statement_expression(const statement_expression_t *expression)
 686 {
 687         fputc('(', out);
 688         print_statement(expression->statement);
 689         fputc(')', out);
 690 }
 691
 692 /**
 693  * Prints an expression with parenthesis if needed.
 694  *
 695  * @param expression  the expression to print
 696  * @param top_prec    the precedence of the user of this expression.
 697  */
 698 static void print_expression_prec(const expression_t *expression, unsigned top_prec)
 699 {
 700         unsigned prec = get_expression_precedence(expression->base.kind);
 701         if (print_parenthesis && top_prec != PREC_BOTTOM)
 702                 top_prec = PREC_TOP;
 703         if (top_prec > prec)
 704                 fputc('(', out);
 705         switch(expression->kind) {
 706         case EXPR_UNKNOWN:
 707         case EXPR_INVALID:
 708                 fprintf(out, "*invalid expression*");
 709                 break;
 710         case EXPR_CHARACTER_CONSTANT:
 711                 print_character_constant(&expression->conste);
 712                 break;
 713         case EXPR_WIDE_CHARACTER_CONSTANT:
 714                 print_wide_character_constant(&expression->conste);
 715                 break;
 716         case EXPR_CONST:
 717                 print_const(&expression->conste);
 718                 break;
 719         case EXPR_FUNCTION:
 720         case EXPR_PRETTY_FUNCTION:
 721         case EXPR_STRING_LITERAL:
 722                 print_string_literal(&expression->string);
 723                 break;
 724         case EXPR_WIDE_STRING_LITERAL:
 725                 print_wide_string_literal(&expression->wide_string);
 726                 break;
 727         case EXPR_COMPOUND_LITERAL:
 728                 print_compound_literal(&expression->compound_literal);
 729                 break;
 730         case EXPR_CALL:
 731                 print_call_expression(&expression->call);
 732                 break;
 733         EXPR_BINARY_CASES
 734                 print_binary_expression(&expression->binary);
 735                 break;
 736         case EXPR_REFERENCE:
 737                 print_reference_expression(&expression->reference);
 738                 break;
 739         case EXPR_ARRAY_ACCESS:
 740                 print_array_expression(&expression->array_access);
 741                 break;
 742         EXPR_UNARY_CASES
 743                 print_unary_expression(&expression->unary);
 744                 break;
 745         case EXPR_SIZEOF:
 746         case EXPR_ALIGNOF:
 747                 print_typeprop_expression(&expression->typeprop);
 748                 break;
 749         case EXPR_BUILTIN_SYMBOL:
 750                 print_builtin_symbol(&expression->builtin_symbol);
 751                 break;
 752         case EXPR_BUILTIN_CONSTANT_P:
 753                 print_builtin_constant(&expression->builtin_constant);
 754                 break;
 755         case EXPR_BUILTIN_PREFETCH:
 756                 print_builtin_prefetch(&expression->builtin_prefetch);
 757                 break;
 758         case EXPR_CONDITIONAL:
 759                 print_conditional(&expression->conditional);
 760                 break;
 761         case EXPR_VA_START:
 762                 print_va_start(&expression->va_starte);
 763                 break;
 764         case EXPR_VA_ARG:
 765                 print_va_arg(&expression->va_arge);
 766                 break;
 767         case EXPR_SELECT:
 768                 print_select(&expression->select);
 769                 break;
 770         case EXPR_CLASSIFY_TYPE:
 771                 print_classify_type_expression(&expression->classify_type);
 772                 break;
 773         case EXPR_OFFSETOF:
 774                 print_offsetof_expression(&expression->offsetofe);
 775                 break;
 776         case EXPR_STATEMENT:
 777                 print_statement_expression(&expression->statement);
 778                 break;
 779
 780         default:
 781                 /* TODO */
 782                 fprintf(out, "some expression of type %d", (int) expression->kind);
 783                 break;
 784         }
 785         if (top_prec > prec)
 786                 fputc(')', out);
 787 }
 788
 789 /**
 790  * Print an compound statement.
 791  *
 792  * @param block  the compound statement
 793  */
 794 static void print_compound_statement(const compound_statement_t *block)
 795 {
 796         fputs("{\n", out);
 797         ++indent;
 798
 799         statement_t *statement = block->statements;
 800         while(statement != NULL) {
 801                 if (statement->base.kind == STATEMENT_CASE_LABEL)
 802                         --indent;
 803                 print_indent();
 804                 print_statement(statement);
 805
 806                 statement = statement->base.next;
 807         }
 808         --indent;
 809         print_indent();
 810         fputs("}\n", out);
 811 }
 812
 813 /**
 814  * Print a return statement.
 815  *
 816  * @param statement  the return statement
 817  */
 818 static void print_return_statement(const return_statement_t *statement)
 819 {
 820         fprintf(out, "return ");
 821         if(statement->value != NULL)
 822                 print_expression(statement->value);
 823         fputs(";\n", out);
 824 }
 825
 826 /**
 827  * Print an expression statement.
 828  *
 829  * @param statement  the expression statement
 830  */
 831 static void print_expression_statement(const expression_statement_t *statement)
 832 {
 833         print_expression(statement->expression);
 834         fputs(";\n", out);
 835 }
 836
 837 /**
 838  * Print a goto statement.
 839  *
 840  * @param statement  the goto statement
 841  */
 842 static void print_goto_statement(const goto_statement_t *statement)
 843 {
 844         fprintf(out, "goto ");
 845         fputs(statement->label->symbol->string, out);
 846         fprintf(stderr, "(%p)", (void*) statement->label);
 847         fputs(";\n", out);
 848 }
 849
 850 /**
 851  * Print a label statement.
 852  *
 853  * @param statement  the label statement
 854  */
 855 static void print_label_statement(const label_statement_t *statement)
 856 {
 857         fprintf(stderr, "(%p)", (void*) statement->label);
 858         fprintf(out, "%s:\n", statement->label->symbol->string);
 859         if(statement->statement != NULL) {
 860                 print_statement(statement->statement);
 861         }
 862 }
 863
 864 /**
 865  * Print an if statement.
 866  *
 867  * @param statement  the if statement
 868  */
 869 static void print_if_statement(const if_statement_t *statement)
 870 {
 871         fputs("if(", out);
 872         print_expression(statement->condition);
 873         fputs(") ", out);
 874         if(statement->true_statement != NULL) {
 875                 print_statement(statement->true_statement);
 876         }
 877
 878         if(statement->false_statement != NULL) {
 879                 print_indent();
 880                 fputs("else ", out);
 881                 print_statement(statement->false_statement);
 882         }
 883 }
 884
 885 /**
 886  * Print a switch statement.
 887  *
 888  * @param statement  the switch statement
 889  */
 890 static void print_switch_statement(const switch_statement_t *statement)
 891 {
 892         fputs("switch(", out);
 893         print_expression(statement->expression);
 894         fputs(") ", out);
 895         print_statement(statement->body);
 896 }
 897
 898 /**
 899  * Print a case label (including the default label).
 900  *
 901  * @param statement  the case label statement
 902  */
 903 static void print_case_label(const case_label_statement_t *statement)
 904 {
 905         if(statement->expression == NULL) {
 906                 fputs("default:\n", out);
 907         } else {
 908                 fputs("case ", out);
 909                 print_expression(statement->expression);
 910                 if (statement->end_range != NULL) {
 911                         fputs(" ... ", out);
 912                         print_expression(statement->end_range);
 913                 }
 914                 fputs(":\n", out);
 915         }
 916         ++indent;
 917         if(statement->statement != NULL) {
 918                 if (statement->statement->base.kind == STATEMENT_CASE_LABEL) {
 919                         --indent;
 920                 }
 921                 print_indent();
 922                 print_statement(statement->statement);
 923         }
 924 }
 925
 926 /**
 927  * Print a declaration statement.
 928  *
 929  * @param statement   the statement
 930  */
 931 static void print_declaration_statement(
 932                 const declaration_statement_t *statement)
 933 {
 934         int first = 1;
 935         declaration_t *declaration = statement->declarations_begin;
 936         for( ; declaration != statement->declarations_end->next;
 937                declaration = declaration->next) {
 938                 if(!first) {
 939                         print_indent();
 940                 } else {
 941                         first = 0;
 942                 }
 943                 print_declaration(declaration);
 944                 fputc('\n', out);
 945         }
 946 }
 947
 948 /**
 949  * Print a while statement.
 950  *
 951  * @param statement   the statement
 952  */
 953 static void print_while_statement(const while_statement_t *statement)
 954 {
 955         fputs("while(", out);
 956         print_expression(statement->condition);
 957         fputs(") ", out);
 958         print_statement(statement->body);
 959 }
 960
 961 /**
 962  * Print a do-while statement.
 963  *
 964  * @param statement   the statement
 965  */
 966 static void print_do_while_statement(const do_while_statement_t *statement)
 967 {
 968         fputs("do ", out);
 969         print_statement(statement->body);
 970         print_indent();
 971         fputs("while(", out);
 972         print_expression(statement->condition);
 973         fputs(");\n", out);
 974 }
 975
 976 /**
 977  * Print a for statement.
 978  *
 979  * @param statement   the statement
 980  */
 981 static void print_for_statement(const for_statement_t *statement)
 982 {
 983         fputs("for(", out);
 984         if(statement->scope.declarations != NULL) {
 985                 assert(statement->initialisation == NULL);
 986                 print_declaration(statement->scope.declarations);
 987                 if(statement->scope.declarations->next != NULL) {
 988                         panic("multiple declarations in for statement not supported yet");
 989                 }
 990                 fputc(' ', out);
 991         } else {
 992                 if(statement->initialisation) {
 993                         print_expression(statement->initialisation);
 994                 }
 995                 fputs("; ", out);
 996         }
 997         if(statement->condition != NULL) {
 998                 print_expression(statement->condition);
 999         }
1000         fputs("; ", out);
1001         if(statement->step != NULL) {
1002                 print_expression(statement->step);
1003         }
1004         fputs(")", out);
1005         print_statement(statement->body);
1006 }
1007
1008 /**
1009  * Print assembler constraints.
1010  *
1011  * @param constraints   the constraints
1012  */
1013 static void print_asm_constraints(asm_constraint_t *constraints)
1014 {
1015         asm_constraint_t *constraint = constraints;
1016         for( ; constraint != NULL; constraint = constraint->next) {
1017                 if(constraint != constraints)
1018                         fputs(", ", out);
1019
1020                 if(constraint->symbol) {
1021                         fprintf(out, "[%s] ", constraint->symbol->string);
1022                 }
1023                 print_quoted_string(&constraint->constraints, '"');
1024                 fputs(" (", out);
1025                 print_expression(constraint->expression);
1026                 fputs(")", out);
1027         }
1028 }
1029
1030 /**
1031  * Print assembler clobbers.
1032  *
1033  * @param clobbers   the clobbers
1034  */
1035 static void print_asm_clobbers(asm_clobber_t *clobbers)
1036 {
1037         asm_clobber_t *clobber = clobbers;
1038         for( ; clobber != NULL; clobber = clobber->next) {
1039                 if(clobber != clobbers)
1040                         fputs(", ", out);
1041
1042                 print_quoted_string(&clobber->clobber, '"');
1043         }
1044 }
1045
1046 /**
1047  * Print an assembler statement.
1048  *
1049  * @param statement   the statement
1050  */
1051 static void print_asm_statement(const asm_statement_t *statement)
1052 {
1053         fputs("asm ", out);
1054         if(statement->is_volatile) {
1055                 fputs("volatile ", out);
1056         }
1057         fputs("(", out);
1058         print_quoted_string(&statement->asm_text, '"');
1059         if(statement->inputs == NULL && statement->outputs == NULL
1060                         && statement->clobbers == NULL)
1061                 goto end_of_print_asm_statement;
1062
1063         fputs(" : ", out);
1064         print_asm_constraints(statement->inputs);
1065         if(statement->outputs == NULL && statement->clobbers == NULL)
1066                 goto end_of_print_asm_statement;
1067
1068         fputs(" : ", out);
1069         print_asm_constraints(statement->outputs);
1070         if(statement->clobbers == NULL)
1071                 goto end_of_print_asm_statement;
1072
1073         fputs(" : ", out);
1074         print_asm_clobbers(statement->clobbers);
1075
1076 end_of_print_asm_statement:
1077         fputs(");\n", out);
1078 }
1079
1080 /**
1081  * Print a statement.
1082  *
1083  * @param statement   the statement
1084  */
1085 void print_statement(const statement_t *statement)
1086 {
1087         switch(statement->kind) {
1088         case STATEMENT_COMPOUND:
1089                 print_compound_statement(&statement->compound);
1090                 break;
1091         case STATEMENT_RETURN:
1092                 print_return_statement(&statement->returns);
1093                 break;
1094         case STATEMENT_EXPRESSION:
1095                 print_expression_statement(&statement->expression);
1096                 break;
1097         case STATEMENT_LABEL:
1098                 print_label_statement(&statement->label);
1099                 break;
1100         case STATEMENT_GOTO:
1101                 print_goto_statement(&statement->gotos);
1102                 break;
1103         case STATEMENT_CONTINUE:
1104                 fputs("continue;\n", out);
1105                 break;
1106         case STATEMENT_BREAK:
1107                 fputs("break;\n", out);
1108                 break;
1109         case STATEMENT_IF:
1110                 print_if_statement(&statement->ifs);
1111                 break;
1112         case STATEMENT_SWITCH:
1113                 print_switch_statement(&statement->switchs);
1114                 break;
1115         case STATEMENT_CASE_LABEL:
1116                 print_case_label(&statement->case_label);
1117                 break;
1118         case STATEMENT_DECLARATION:
1119                 print_declaration_statement(&statement->declaration);
1120                 break;
1121         case STATEMENT_WHILE:
1122                 print_while_statement(&statement->whiles);
1123                 break;
1124         case STATEMENT_DO_WHILE:
1125                 print_do_while_statement(&statement->do_while);
1126                 break;
1127         case STATEMENT_FOR:
1128                 print_for_statement(&statement->fors);
1129                 break;
1130         case STATEMENT_ASM:
1131                 print_asm_statement(&statement->asms);
1132                 break;
1133         case STATEMENT_INVALID:
1134                 fprintf(out, "*invalid statement*");
1135                 break;
1136         }
1137 }
1138
1139 /**
1140  * Print a storage class.
1141  *
1142  * @param storage_class   the storage class
1143  */
1144 static void print_storage_class(storage_class_tag_t storage_class)
1145 {
1146         switch(storage_class) {
1147         case STORAGE_CLASS_ENUM_ENTRY:
1148         case STORAGE_CLASS_NONE:
1149                 break;
1150         case STORAGE_CLASS_TYPEDEF:       fputs("typedef ",        out); break;
1151         case STORAGE_CLASS_EXTERN:        fputs("extern ",         out); break;
1152         case STORAGE_CLASS_STATIC:        fputs("static ",         out); break;
1153         case STORAGE_CLASS_AUTO:          fputs("auto ",           out); break;
1154         case STORAGE_CLASS_REGISTER:      fputs("register ",       out); break;
1155         case STORAGE_CLASS_THREAD:        fputs("__thread",        out); break;
1156         case STORAGE_CLASS_THREAD_EXTERN: fputs("extern __thread", out); break;
1157         case STORAGE_CLASS_THREAD_STATIC: fputs("static __thread", out); break;
1158         }
1159 }
1160
1161 /**
1162  * Print an initializer.
1163  *
1164  * @param initializer  the initializer
1165  */
1166 void print_initializer(const initializer_t *initializer)
1167 {
1168         if(initializer == NULL) {
1169                 fputs("{ NIL-INITIALIZER }", out);
1170                 return;
1171         }
1172
1173         switch(initializer->kind) {
1174         case INITIALIZER_VALUE: {
1175                 const initializer_value_t *value = &initializer->value;
1176                 print_expression(value->value);
1177                 return;
1178         }
1179         case INITIALIZER_LIST: {
1180                 assert(initializer->kind == INITIALIZER_LIST);
1181                 fputs("{ ", out);
1182                 const initializer_list_t *list = &initializer->list;
1183
1184                 for(size_t i = 0 ; i < list->len; ++i) {
1185                         const initializer_t *sub_init = list->initializers[i];
1186                         print_initializer(list->initializers[i]);
1187                         if(i < list->len-1 && sub_init->kind != INITIALIZER_DESIGNATOR) {
1188                                 fputs(", ", out);
1189                         }
1190                 }
1191                 fputs(" }", out);
1192                 return;
1193         }
1194         case INITIALIZER_STRING:
1195                 print_quoted_string(&initializer->string.string, '"');
1196                 return;
1197         case INITIALIZER_WIDE_STRING:
1198                 print_quoted_wide_string(&initializer->wide_string.string, '"');
1199                 return;
1200         case INITIALIZER_DESIGNATOR:
1201                 print_designator(initializer->designator.designator);
1202                 fputs(" = ", out);
1203                 return;
1204         }
1205
1206         panic("invalid initializer kind found");
1207 }
1208
1209 /**
1210  * Print a declaration in the NORMAL namespace.
1211  *
1212  * @param declaration  the declaration
1213  */
1214 static void print_normal_declaration(const declaration_t *declaration)
1215 {
1216         print_storage_class((storage_class_tag_t) declaration->declared_storage_class);
1217         if(declaration->is_inline) {
1218                 if (declaration->modifiers & DM_FORCEINLINE)
1219                         fputs("__forceinline ", out);
1220                 else
1221                         fputs("inline ", out);
1222         }
1223         print_type_ext(declaration->type, declaration->symbol,
1224                        &declaration->scope);
1225
1226         if(declaration->type->kind == TYPE_FUNCTION) {
1227                 if(declaration->init.statement != NULL) {
1228                         fputs("\n", out);
1229                         print_statement(declaration->init.statement);
1230                         return;
1231                 }
1232         } else if(declaration->init.initializer != NULL) {
1233                 fputs(" = ", out);
1234                 print_initializer(declaration->init.initializer);
1235         }
1236         fputc(';', out);
1237 }
1238
1239 /**
1240  * Prints an expression.
1241  *
1242  * @param expression  the expression
1243  */
1244 void print_expression(const expression_t *expression) {
1245         print_expression_prec(expression, PREC_BOTTOM);
1246 }
1247
1248 /**
1249  * Print a declaration.
1250  *
1251  * @param declaration  the declaration
1252  */
1253 void print_declaration(const declaration_t *declaration)
1254 {
1255         if(declaration->namespc != NAMESPACE_NORMAL &&
1256                         declaration->symbol == NULL)
1257                 return;
1258
1259         switch(declaration->namespc) {
1260         case NAMESPACE_NORMAL:
1261                 print_normal_declaration(declaration);
1262                 break;
1263         case NAMESPACE_STRUCT:
1264                 fputs("struct ", out);
1265                 fputs(declaration->symbol->string, out);
1266                 fputc(' ', out);
1267                 print_compound_definition(declaration);
1268                 fputc(';', out);
1269                 break;
1270         case NAMESPACE_UNION:
1271                 fputs("union ", out);
1272                 fputs(declaration->symbol->string, out);
1273                 fputc(' ', out);
1274                 print_compound_definition(declaration);
1275                 fputc(';', out);
1276                 break;
1277         case NAMESPACE_ENUM:
1278                 fputs("enum ", out);
1279                 fputs(declaration->symbol->string, out);
1280                 fputc(' ', out);
1281                 print_enum_definition(declaration);
1282                 fputc(';', out);
1283                 break;
1284         }
1285 }
1286
1287 /**
1288  * Print the AST of a translation unit.
1289  *
1290  * @param unit   the translation unit
1291  */
1292 void print_ast(const translation_unit_t *unit)
1293 {
1294         inc_type_visited();
1295
1296         declaration_t *declaration = unit->scope.declarations;
1297         for( ; declaration != NULL; declaration = declaration->next) {
1298                 if(declaration->storage_class == STORAGE_CLASS_ENUM_ENTRY)
1299                         continue;
1300                 if(declaration->namespc != NAMESPACE_NORMAL &&
1301                                 declaration->symbol == NULL)
1302                         continue;
1303
1304                 print_indent();
1305                 print_declaration(declaration);
1306                 fputc('\n', out);
1307         }
1308 }
1309
1310 bool is_constant_initializer(const initializer_t *initializer)
1311 {
1312         switch(initializer->kind) {
1313         case INITIALIZER_STRING:
1314         case INITIALIZER_WIDE_STRING:
1315         case INITIALIZER_DESIGNATOR:
1316                 return true;
1317
1318         case INITIALIZER_VALUE:
1319                 return is_constant_expression(initializer->value.value);
1320
1321         case INITIALIZER_LIST: {
1322                 for(size_t i = 0; i < initializer->list.len; ++i) {
1323                         initializer_t *sub_initializer = initializer->list.initializers[i];
1324                         if(!is_constant_initializer(sub_initializer))
1325                                 return false;
1326                 }
1327                 return true;
1328         }
1329         }
1330         panic("invalid initializer kind found");
1331 }
1332
1333 static bool is_object_with_constant_address(const expression_t *expression)
1334 {
1335         switch(expression->kind) {
1336         case EXPR_UNARY_DEREFERENCE:
1337                 return is_address_constant(expression->unary.value);
1338
1339         case EXPR_SELECT: {
1340                 if(is_type_pointer(expression->select.compound->base.type)) {
1341                         /* it's a -> */
1342                         return is_address_constant(expression->select.compound);
1343                 } else {
1344                         return is_object_with_constant_address(expression->select.compound);
1345                 }
1346         }
1347
1348         case EXPR_ARRAY_ACCESS:
1349                 return is_constant_expression(expression->array_access.index)
1350                         && is_address_constant(expression->array_access.array_ref);
1351
1352         case EXPR_REFERENCE: {
1353                 declaration_t *declaration = expression->reference.declaration;
1354                 switch((storage_class_tag_t) declaration->storage_class) {
1355                 case STORAGE_CLASS_NONE:
1356                 case STORAGE_CLASS_EXTERN:
1357                 case STORAGE_CLASS_STATIC:
1358                         return true;
1359                 default:
1360                         return false;
1361                 }
1362         }
1363
1364         default:
1365                 return false;
1366         }
1367 }
1368
1369 bool is_address_constant(const expression_t *expression)
1370 {
1371         switch(expression->kind) {
1372         case EXPR_UNARY_TAKE_ADDRESS:
1373                 return is_object_with_constant_address(expression->unary.value);
1374
1375         case EXPR_UNARY_CAST:
1376                 return is_type_pointer(skip_typeref(expression->base.type))
1377                         && (is_constant_expression(expression->unary.value)
1378                         || is_address_constant(expression->unary.value));
1379
1380         case EXPR_BINARY_ADD:
1381         case EXPR_BINARY_SUB: {
1382                 expression_t *left  = expression->binary.left;
1383                 expression_t *right = expression->binary.right;
1384
1385                 if(is_type_pointer(skip_typeref(left->base.type))) {
1386                         return is_address_constant(left) && is_constant_expression(right);
1387                 } else if(is_type_pointer(skip_typeref(right->base.type))) {
1388                         return is_constant_expression(left)     && is_address_constant(right);
1389                 }
1390
1391                 return false;
1392         }
1393
1394         case EXPR_REFERENCE: {
1395                 declaration_t *declaration = expression->reference.declaration;
1396                 type_t *type = skip_typeref(declaration->type);
1397                 if(is_type_function(type))
1398                         return true;
1399                 if(is_type_array(type)) {
1400                         return is_object_with_constant_address(expression);
1401                 }
1402                 return false;
1403         }
1404
1405         default:
1406                 return false;
1407         }
1408 }
1409
1410 bool is_constant_expression(const expression_t *expression)
1411 {
1412         switch(expression->kind) {
1413
1414         case EXPR_CONST:
1415         case EXPR_CHARACTER_CONSTANT:
1416         case EXPR_WIDE_CHARACTER_CONSTANT:
1417         case EXPR_STRING_LITERAL:
1418         case EXPR_WIDE_STRING_LITERAL:
1419         case EXPR_SIZEOF:
1420         case EXPR_CLASSIFY_TYPE:
1421         case EXPR_FUNCTION:
1422         case EXPR_PRETTY_FUNCTION:
1423         case EXPR_OFFSETOF:
1424         case EXPR_ALIGNOF:
1425         case EXPR_BUILTIN_CONSTANT_P:
1426                 return true;
1427
1428         case EXPR_BUILTIN_SYMBOL:
1429         case EXPR_BUILTIN_PREFETCH:
1430         case EXPR_CALL:
1431         case EXPR_SELECT:
1432         case EXPR_VA_START:
1433         case EXPR_VA_ARG:
1434         case EXPR_STATEMENT:
1435         case EXPR_UNARY_POSTFIX_INCREMENT:
1436         case EXPR_UNARY_POSTFIX_DECREMENT:
1437         case EXPR_UNARY_PREFIX_INCREMENT:
1438         case EXPR_UNARY_PREFIX_DECREMENT:
1439         case EXPR_UNARY_BITFIELD_EXTRACT:
1440         case EXPR_UNARY_ASSUME: /* has VOID type */
1441         case EXPR_UNARY_DEREFERENCE:
1442         case EXPR_UNARY_TAKE_ADDRESS:
1443         case EXPR_BINARY_ASSIGN:
1444         case EXPR_BINARY_MUL_ASSIGN:
1445         case EXPR_BINARY_DIV_ASSIGN:
1446         case EXPR_BINARY_MOD_ASSIGN:
1447         case EXPR_BINARY_ADD_ASSIGN:
1448         case EXPR_BINARY_SUB_ASSIGN:
1449         case EXPR_BINARY_SHIFTLEFT_ASSIGN:
1450         case EXPR_BINARY_SHIFTRIGHT_ASSIGN:
1451         case EXPR_BINARY_BITWISE_AND_ASSIGN:
1452         case EXPR_BINARY_BITWISE_XOR_ASSIGN:
1453         case EXPR_BINARY_BITWISE_OR_ASSIGN:
1454         case EXPR_BINARY_COMMA:
1455                 return false;
1456
1457         case EXPR_UNARY_NEGATE:
1458         case EXPR_UNARY_PLUS:
1459         case EXPR_UNARY_BITWISE_NEGATE:
1460         case EXPR_UNARY_NOT:
1461                 return is_constant_expression(expression->unary.value);
1462
1463         case EXPR_UNARY_CAST:
1464         case EXPR_UNARY_CAST_IMPLICIT:
1465                 return is_type_arithmetic(skip_typeref(expression->base.type))
1466                         && is_constant_expression(expression->unary.value);
1467
1468         case EXPR_BINARY_ADD:
1469         case EXPR_BINARY_SUB:
1470         case EXPR_BINARY_MUL:
1471         case EXPR_BINARY_DIV:
1472         case EXPR_BINARY_MOD:
1473         case EXPR_BINARY_EQUAL:
1474         case EXPR_BINARY_NOTEQUAL:
1475         case EXPR_BINARY_LESS:
1476         case EXPR_BINARY_LESSEQUAL:
1477         case EXPR_BINARY_GREATER:
1478         case EXPR_BINARY_GREATEREQUAL:
1479         case EXPR_BINARY_BITWISE_AND:
1480         case EXPR_BINARY_BITWISE_OR:
1481         case EXPR_BINARY_BITWISE_XOR:
1482         case EXPR_BINARY_LOGICAL_AND:
1483         case EXPR_BINARY_LOGICAL_OR:
1484         case EXPR_BINARY_SHIFTLEFT:
1485         case EXPR_BINARY_SHIFTRIGHT:
1486         case EXPR_BINARY_BUILTIN_EXPECT:
1487         case EXPR_BINARY_ISGREATER:
1488         case EXPR_BINARY_ISGREATEREQUAL:
1489         case EXPR_BINARY_ISLESS:
1490         case EXPR_BINARY_ISLESSEQUAL:
1491         case EXPR_BINARY_ISLESSGREATER:
1492         case EXPR_BINARY_ISUNORDERED:
1493                 return is_constant_expression(expression->binary.left)
1494                         && is_constant_expression(expression->binary.right);
1495
1496         case EXPR_COMPOUND_LITERAL:
1497                 return is_constant_initializer(expression->compound_literal.initializer);
1498
1499         case EXPR_CONDITIONAL: {
1500                 expression_t *condition = expression->conditional.condition;
1501                 if(!is_constant_expression(condition))
1502                         return false;
1503
1504                 long val = fold_constant(condition);
1505                 if(val != 0)
1506                         return is_constant_expression(expression->conditional.true_expression);
1507                 else
1508                         return is_constant_expression(expression->conditional.false_expression);
1509         }
1510
1511         case EXPR_ARRAY_ACCESS:
1512                 return is_constant_expression(expression->array_access.array_ref)
1513                         && is_constant_expression(expression->array_access.index);
1514
1515         case EXPR_REFERENCE: {
1516                 declaration_t *declaration = expression->reference.declaration;
1517                 if(declaration->storage_class == STORAGE_CLASS_ENUM_ENTRY)
1518                         return true;
1519
1520                 return false;
1521         }
1522
1523         case EXPR_UNKNOWN:
1524         case EXPR_INVALID:
1525                 break;
1526         }
1527         panic("invalid expression found (is constant expression)");
1528 }
1529
1530 /**
1531  * Initialize the AST construction.
1532  */
1533 void init_ast(void)
1534 {
1535         obstack_init(&ast_obstack);
1536 }
1537
1538 /**
1539  * Free the AST.
1540  */
1541 void exit_ast(void)
1542 {
1543         obstack_free(&ast_obstack, NULL);
1544 }
1545
1546 /**
1547  * Set the output stream for the AST printer.
1548  *
1549  * @param stream  the output stream
1550  */
1551 void ast_set_output(FILE *stream)
1552 {
1553         out = stream;
1554         type_set_output(stream);
1555 }
1556
1557 /**
1558  * Allocate an AST object of the given size.
1559  *
1560  * @param size  the size of the object to allocate
1561  *
1562  * @return  A new allocated object in the AST memeory space.
1563  */
1564 void *(allocate_ast)(size_t size)
1565 {
1566         return _allocate_ast(size);
1567 }