tccrun.c

   1 /*
   2  *  TCC - Tiny C Compiler - Support for -run switch
   3  *
   4  *  Copyright (c) 2001-2004 Fabrice Bellard
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20
  21 #include "tcc.h"
  22
  23 /* only native compiler supports -run */
  24 #ifdef TCC_IS_NATIVE
  25
  26 #ifdef CONFIG_TCC_BACKTRACE
  27 ST_DATA int rt_num_callers = 6;
  28 ST_DATA const char **rt_bound_error_msg;
  29 ST_DATA void *rt_prog_main;
  30 #endif
  31
  32 #ifdef _WIN32
  33 #define ucontext_t CONTEXT
  34 #endif
  35
  36 static void set_pages_executable(void *ptr, unsigned long length);
  37 static void set_exception_handler(void);
  38 static int rt_get_caller_pc(addr_t *paddr, ucontext_t *uc, int level);
  39 static void rt_error(ucontext_t *uc, const char *fmt, ...);
  40 static int tcc_relocate_ex(TCCState *s1, void *ptr);
  41
  42 #ifdef _WIN64
  43 static void win64_add_function_table(TCCState *s1);
  44 #endif
  45
  46 /* ------------------------------------------------------------- */
  47 /* Do all relocations (needed before using tcc_get_symbol())
  48    Returns -1 on error. */
  49
  50 LIBTCCAPI int tcc_relocate(TCCState *s1, void *ptr)
  51 {
  52     int ret;
  53
  54     if (TCC_RELOCATE_AUTO != ptr)
  55         return tcc_relocate_ex(s1, ptr);
  56
  57     ret = tcc_relocate_ex(s1, NULL);
  58     if (ret < 0)
  59         return ret;
  60
  61 #ifdef HAVE_SELINUX
  62     {   /* Use mmap instead of malloc for Selinux.  Ref:
  63            http://www.gnu.org/s/libc/manual/html_node/File-Size.html */
  64
  65         char tmpfname[] = "/tmp/.tccrunXXXXXX";
  66         int fd = mkstemp (tmpfname);
  67
  68         s1->mem_size = ret;
  69         unlink (tmpfname);
  70         ftruncate (fd, s1->mem_size);
  71
  72         s1->write_mem = mmap (NULL, ret, PROT_READ|PROT_WRITE,
  73             MAP_SHARED, fd, 0);
  74         if (s1->write_mem == MAP_FAILED)
  75             tcc_error("/tmp not writeable");
  76
  77         s1->runtime_mem = mmap (NULL, ret, PROT_READ|PROT_EXEC,
  78             MAP_SHARED, fd, 0);
  79         if (s1->runtime_mem == MAP_FAILED)
  80             tcc_error("/tmp not executable");
  81
  82         ret = tcc_relocate_ex(s1, s1->write_mem);
  83     }
  84 #else
  85     s1->runtime_mem = tcc_malloc(ret);
  86     ret = tcc_relocate_ex(s1, s1->runtime_mem);
  87 #endif
  88     return ret;
  89 }
  90
  91 /* launch the compiled program with the given arguments */
  92 LIBTCCAPI int tcc_run(TCCState *s1, int argc, char **argv)
  93 {
  94     int (*prog_main)(int, char **);
  95
  96     if (tcc_relocate(s1, TCC_RELOCATE_AUTO) < 0)
  97         return -1;
  98     prog_main = tcc_get_symbol_err(s1, s1->runtime_main);
  99
 100 #ifdef CONFIG_TCC_BACKTRACE
 101     if (s1->do_debug) {
 102         set_exception_handler();
 103         rt_prog_main = prog_main;
 104     }
 105 #endif
 106
 107     errno = 0; /* clean errno value */
 108
 109 #ifdef CONFIG_TCC_BCHECK
 110     if (s1->do_bounds_check) {
 111         void (*bound_init)(void);
 112         void (*bound_exit)(void);
 113         void (*bound_new_region)(void *p, addr_t size);
 114         int  (*bound_delete_region)(void *p);
 115         int i, ret;
 116
 117         /* set error function */
 118         rt_bound_error_msg = tcc_get_symbol_err(s1, "__bound_error_msg");
 119         /* XXX: use .init section so that it also work in binary ? */
 120         bound_init = tcc_get_symbol_err(s1, "__bound_init");
 121         bound_exit = tcc_get_symbol_err(s1, "__bound_exit");
 122         bound_new_region = tcc_get_symbol_err(s1, "__bound_new_region");
 123         bound_delete_region = tcc_get_symbol_err(s1, "__bound_delete_region");
 124
 125         bound_init();
 126         /* mark argv area as valid */
 127         bound_new_region(argv, argc*sizeof(argv[0]));
 128         for (i=0; i<argc; ++i)
 129             bound_new_region(argv[i], strlen(argv[i]) + 1);
 130
 131         ret = (*prog_main)(argc, argv);
 132
 133         /* unmark argv area */
 134         for (i=0; i<argc; ++i)
 135             bound_delete_region(argv[i]);
 136         bound_delete_region(argv);
 137         bound_exit();
 138         return ret;
 139     }
 140 #endif
 141     return (*prog_main)(argc, argv);
 142 }
 143
 144 /* relocate code. Return -1 on error, required size if ptr is NULL,
 145    otherwise copy code into buffer passed by the caller */
 146 static int tcc_relocate_ex(TCCState *s1, void *ptr)
 147 {
 148     Section *s;
 149     unsigned long offset, length;
 150     addr_t mem;
 151     int i;
 152
 153     if (NULL == ptr) {
 154         s1->nb_errors = 0;
 155 #ifdef TCC_TARGET_PE
 156         pe_output_file(s1, NULL);
 157 #else
 158         tcc_add_runtime(s1);
 159         relocate_common_syms();
 160         tcc_add_linker_symbols(s1);
 161         build_got_entries(s1);
 162 #endif
 163         if (s1->nb_errors)
 164             return -1;
 165     }
 166
 167     offset = 0, mem = (addr_t)ptr;
 168     for(i = 1; i < s1->nb_sections; i++) {
 169         s = s1->sections[i];
 170         if (0 == (s->sh_flags & SHF_ALLOC))
 171             continue;
 172         length = s->data_offset;
 173         s->sh_addr = mem ? (mem + offset + 15) & ~15 : 0;
 174         offset = (offset + length + 15) & ~15;
 175     }
 176     offset += 16;
 177
 178     /* relocate symbols */
 179     relocate_syms(s1, 1);
 180     if (s1->nb_errors)
 181         return -1;
 182
 183     if (0 == mem)
 184         return offset;
 185
 186     /* relocate each section */
 187     for(i = 1; i < s1->nb_sections; i++) {
 188         s = s1->sections[i];
 189         if (s->reloc)
 190             relocate_section(s1, s);
 191     }
 192     relocate_plt(s1);
 193
 194     for(i = 1; i < s1->nb_sections; i++) {
 195         s = s1->sections[i];
 196         if (0 == (s->sh_flags & SHF_ALLOC))
 197             continue;
 198         length = s->data_offset;
 199         // printf("%-12s %08lx %04x\n", s->name, s->sh_addr, length);
 200         ptr = (void*)s->sh_addr;
 201         if (NULL == s->data || s->sh_type == SHT_NOBITS)
 202             memset(ptr, 0, length);
 203         else
 204             memcpy(ptr, s->data, length);
 205         /* mark executable sections as executable in memory */
 206         if (s->sh_flags & SHF_EXECINSTR)
 207             set_pages_executable(ptr, length);
 208     }
 209
 210 #ifdef _WIN64
 211     win64_add_function_table(s1);
 212 #endif
 213     return 0;
 214 }
 215
 216 /* ------------------------------------------------------------- */
 217 /* allow to run code in memory */
 218
 219 static void set_pages_executable(void *ptr, unsigned long length)
 220 {
 221 #ifdef _WIN32
 222     unsigned long old_protect;
 223     VirtualProtect(ptr, length, PAGE_EXECUTE_READWRITE, &old_protect);
 224 #else
 225     extern void __clear_cache(void *beginning, void *end);
 226 #ifndef PAGESIZE
 227 # define PAGESIZE 4096
 228 #endif
 229     addr_t start, end;
 230     start = (addr_t)ptr & ~(PAGESIZE - 1);
 231     end = (addr_t)ptr + length;
 232     end = (end + PAGESIZE - 1) & ~(PAGESIZE - 1);
 233     mprotect((void *)start, end - start, PROT_READ | PROT_WRITE | PROT_EXEC);
 234   #ifndef __PCC__
 235     __clear_cache(ptr, (char *)ptr + length);
 236   #else
 237     /* pcc 1.2.0.DEVEL 20141206 don't have such proc */
 238   #endif
 239 #endif
 240 }
 241
 242 /* ------------------------------------------------------------- */
 243 #ifdef CONFIG_TCC_BACKTRACE
 244
 245 ST_FUNC void tcc_set_num_callers(int n)
 246 {
 247     rt_num_callers = n;
 248 }
 249
 250 /* print the position in the source file of PC value 'pc' by reading
 251    the stabs debug information */
 252 static addr_t rt_printline(addr_t wanted_pc, const char *msg)
 253 {
 254     char func_name[128], last_func_name[128];
 255     addr_t func_addr, last_pc, pc;
 256     const char *incl_files[INCLUDE_STACK_SIZE];
 257     int incl_index, len, last_line_num, i;
 258     const char *str, *p;
 259
 260     Stab_Sym *stab_sym = NULL, *stab_sym_end, *sym;
 261     int stab_len = 0;
 262     char *stab_str = NULL;
 263
 264     if (stab_section) {
 265         stab_len = stab_section->data_offset;
 266         stab_sym = (Stab_Sym *)stab_section->data;
 267         stab_str = (char *) stabstr_section->data;
 268     }
 269
 270     func_name[0] = '\0';
 271     func_addr = 0;
 272     incl_index = 0;
 273     last_func_name[0] = '\0';
 274     last_pc = (addr_t)-1;
 275     last_line_num = 1;
 276
 277     if (!stab_sym)
 278         goto no_stabs;
 279
 280     stab_sym_end = (Stab_Sym*)((char*)stab_sym + stab_len);
 281     for (sym = stab_sym + 1; sym < stab_sym_end; ++sym) {
 282         switch(sym->n_type) {
 283             /* function start or end */
 284         case N_FUN:
 285             if (sym->n_strx == 0) {
 286                 /* we test if between last line and end of function */
 287                 pc = sym->n_value + func_addr;
 288                 if (wanted_pc >= last_pc && wanted_pc < pc)
 289                     goto found;
 290                 func_name[0] = '\0';
 291                 func_addr = 0;
 292             } else {
 293                 str = stab_str + sym->n_strx;
 294                 p = strchr(str, ':');
 295                 if (!p) {
 296                     pstrcpy(func_name, sizeof(func_name), str);
 297                 } else {
 298                     len = p - str;
 299                     if (len > sizeof(func_name) - 1)
 300                         len = sizeof(func_name) - 1;
 301                     memcpy(func_name, str, len);
 302                     func_name[len] = '\0';
 303                 }
 304                 func_addr = sym->n_value;
 305             }
 306             break;
 307             /* line number info */
 308         case N_SLINE:
 309             pc = sym->n_value + func_addr;
 310             if (wanted_pc >= last_pc && wanted_pc < pc)
 311                 goto found;
 312             last_pc = pc;
 313             last_line_num = sym->n_desc;
 314             /* XXX: slow! */
 315             strcpy(last_func_name, func_name);
 316             break;
 317             /* include files */
 318         case N_BINCL:
 319             str = stab_str + sym->n_strx;
 320         add_incl:
 321             if (incl_index < INCLUDE_STACK_SIZE) {
 322                 incl_files[incl_index++] = str;
 323             }
 324             break;
 325         case N_EINCL:
 326             if (incl_index > 1)
 327                 incl_index--;
 328             break;
 329         case N_SO:
 330             if (sym->n_strx == 0) {
 331                 incl_index = 0; /* end of translation unit */
 332             } else {
 333                 str = stab_str + sym->n_strx;
 334                 /* do not add path */
 335                 len = strlen(str);
 336                 if (len > 0 && str[len - 1] != '/')
 337                     goto add_incl;
 338             }
 339             break;
 340         }
 341     }
 342
 343 no_stabs:
 344     /* second pass: we try symtab symbols (no line number info) */
 345     incl_index = 0;
 346     if (symtab_section)
 347     {
 348         ElfW(Sym) *sym, *sym_end;
 349         int type;
 350
 351         sym_end = (ElfW(Sym) *)(symtab_section->data + symtab_section->data_offset);
 352         for(sym = (ElfW(Sym) *)symtab_section->data + 1;
 353             sym < sym_end;
 354             sym++) {
 355             type = ELFW(ST_TYPE)(sym->st_info);
 356             if (type == STT_FUNC || type == STT_GNU_IFUNC) {
 357                 if (wanted_pc >= sym->st_value &&
 358                     wanted_pc < sym->st_value + sym->st_size) {
 359                     pstrcpy(last_func_name, sizeof(last_func_name),
 360                             (char *) strtab_section->data + sym->st_name);
 361                     func_addr = sym->st_value;
 362                     goto found;
 363                 }
 364             }
 365         }
 366     }
 367     /* did not find any info: */
 368     fprintf(stderr, "%s %p ???\n", msg, (void*)wanted_pc);
 369     fflush(stderr);
 370     return 0;
 371  found:
 372     i = incl_index;
 373     if (i > 0)
 374         fprintf(stderr, "%s:%d: ", incl_files[--i], last_line_num);
 375     fprintf(stderr, "%s %p", msg, (void*)wanted_pc);
 376     if (last_func_name[0] != '\0')
 377         fprintf(stderr, " %s()", last_func_name);
 378     if (--i >= 0) {
 379         fprintf(stderr, " (included from ");
 380         for (;;) {
 381             fprintf(stderr, "%s", incl_files[i]);
 382             if (--i < 0)
 383                 break;
 384             fprintf(stderr, ", ");
 385         }
 386         fprintf(stderr, ")");
 387     }
 388     fprintf(stderr, "\n");
 389     fflush(stderr);
 390     return func_addr;
 391 }
 392
 393 /* emit a run time error at position 'pc' */
 394 static void rt_error(ucontext_t *uc, const char *fmt, ...)
 395 {
 396     va_list ap;
 397     addr_t pc;
 398     int i;
 399
 400     fprintf(stderr, "Runtime error: ");
 401     va_start(ap, fmt);
 402     vfprintf(stderr, fmt, ap);
 403     va_end(ap);
 404     fprintf(stderr, "\n");
 405
 406     for(i=0;i<rt_num_callers;i++) {
 407         if (rt_get_caller_pc(&pc, uc, i) < 0)
 408             break;
 409         pc = rt_printline(pc, i ? "by" : "at");
 410         if (pc == (addr_t)rt_prog_main && pc)
 411             break;
 412     }
 413 }
 414
 415 /* ------------------------------------------------------------- */
 416 #ifndef _WIN32
 417
 418 /* signal handler for fatal errors */
 419 static void sig_error(int signum, siginfo_t *siginf, void *puc)
 420 {
 421     ucontext_t *uc = puc;
 422
 423     switch(signum) {
 424     case SIGFPE:
 425         switch(siginf->si_code) {
 426         case FPE_INTDIV:
 427         case FPE_FLTDIV:
 428             rt_error(uc, "division by zero");
 429             break;
 430         default:
 431             rt_error(uc, "floating point exception");
 432             break;
 433         }
 434         break;
 435     case SIGBUS:
 436     case SIGSEGV:
 437         if (rt_bound_error_msg && *rt_bound_error_msg)
 438             rt_error(uc, *rt_bound_error_msg);
 439         else
 440             rt_error(uc, "dereferencing invalid pointer");
 441         break;
 442     case SIGILL:
 443         rt_error(uc, "illegal instruction");
 444         break;
 445     case SIGABRT:
 446         rt_error(uc, "abort() called");
 447         break;
 448     default:
 449         rt_error(uc, "caught signal %d", signum);
 450         break;
 451     }
 452     exit(255);
 453 }
 454
 455 #ifndef SA_SIGINFO
 456 # define SA_SIGINFO 0x00000004u
 457 #endif
 458
 459 /* Generate a stack backtrace when a CPU exception occurs. */
 460 static void set_exception_handler(void)
 461 {
 462     struct sigaction sigact;
 463     /* install TCC signal handlers to print debug info on fatal
 464        runtime errors */
 465     sigact.sa_flags = SA_SIGINFO | SA_RESETHAND;
 466     sigact.sa_sigaction = sig_error;
 467     sigemptyset(&sigact.sa_mask);
 468     sigaction(SIGFPE, &sigact, NULL);
 469     sigaction(SIGILL, &sigact, NULL);
 470     sigaction(SIGSEGV, &sigact, NULL);
 471     sigaction(SIGBUS, &sigact, NULL);
 472     sigaction(SIGABRT, &sigact, NULL);
 473 }
 474
 475 /* ------------------------------------------------------------- */
 476 #ifdef __i386__
 477
 478 /* fix for glibc 2.1 */
 479 #ifndef REG_EIP
 480 #define REG_EIP EIP
 481 #define REG_EBP EBP
 482 #endif
 483
 484 /* return the PC at frame level 'level'. Return negative if not found */
 485 static int rt_get_caller_pc(addr_t *paddr, ucontext_t *uc, int level)
 486 {
 487     addr_t fp;
 488     int i;
 489
 490     if (level == 0) {
 491 #if defined(__APPLE__)
 492         *paddr = uc->uc_mcontext->__ss.__eip;
 493 #elif defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__DragonFly__)
 494         *paddr = uc->uc_mcontext.mc_eip;
 495 #elif defined(__dietlibc__)
 496         *paddr = uc->uc_mcontext.eip;
 497 #elif defined(__NetBSD__)
 498         *paddr = uc->uc_mcontext.__gregs[_REG_EIP];
 499 #else
 500         *paddr = uc->uc_mcontext.gregs[REG_EIP];
 501 #endif
 502         return 0;
 503     } else {
 504 #if defined(__APPLE__)
 505         fp = uc->uc_mcontext->__ss.__ebp;
 506 #elif defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__DragonFly__)
 507         fp = uc->uc_mcontext.mc_ebp;
 508 #elif defined(__dietlibc__)
 509         fp = uc->uc_mcontext.ebp;
 510 #elif defined(__NetBSD__)
 511         fp = uc->uc_mcontext.__gregs[_REG_EBP];
 512 #else
 513         fp = uc->uc_mcontext.gregs[REG_EBP];
 514 #endif
 515         for(i=1;i<level;i++) {
 516             /* XXX: check address validity with program info */
 517             if (fp <= 0x1000 || fp >= 0xc0000000)
 518                 return -1;
 519             fp = ((addr_t *)fp)[0];
 520         }
 521         *paddr = ((addr_t *)fp)[1];
 522         return 0;
 523     }
 524 }
 525
 526 /* ------------------------------------------------------------- */
 527 #elif defined(__x86_64__)
 528
 529 /* return the PC at frame level 'level'. Return negative if not found */
 530 static int rt_get_caller_pc(addr_t *paddr, ucontext_t *uc, int level)
 531 {
 532     addr_t fp;
 533     int i;
 534
 535     if (level == 0) {
 536         /* XXX: only support linux */
 537 #if defined(__APPLE__)
 538         *paddr = uc->uc_mcontext->__ss.__rip;
 539 #elif defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__DragonFly__)
 540         *paddr = uc->uc_mcontext.mc_rip;
 541 #elif defined(__NetBSD__)
 542         *paddr = uc->uc_mcontext.__gregs[_REG_RIP];
 543 #else
 544         *paddr = uc->uc_mcontext.gregs[REG_RIP];
 545 #endif
 546         return 0;
 547     } else {
 548 #if defined(__APPLE__)
 549         fp = uc->uc_mcontext->__ss.__rbp;
 550 #elif defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__DragonFly__)
 551         fp = uc->uc_mcontext.mc_rbp;
 552 #elif defined(__NetBSD__)
 553         fp = uc->uc_mcontext.__gregs[_REG_RBP];
 554 #else
 555         fp = uc->uc_mcontext.gregs[REG_RBP];
 556 #endif
 557         for(i=1;i<level;i++) {
 558             /* XXX: check address validity with program info */
 559             if (fp <= 0x1000)
 560                 return -1;
 561             fp = ((addr_t *)fp)[0];
 562         }
 563         *paddr = ((addr_t *)fp)[1];
 564         return 0;
 565     }
 566 }
 567
 568 /* ------------------------------------------------------------- */
 569 #elif defined(__arm__)
 570
 571 /* return the PC at frame level 'level'. Return negative if not found */
 572 static int rt_get_caller_pc(addr_t *paddr, ucontext_t *uc, int level)
 573 {
 574     addr_t fp, sp;
 575     int i;
 576
 577     if (level == 0) {
 578         /* XXX: only supports linux */
 579 #if defined(__linux__)
 580         *paddr = uc->uc_mcontext.arm_pc;
 581 #else
 582         return -1;
 583 #endif
 584         return 0;
 585     } else {
 586 #if defined(__linux__)
 587         fp = uc->uc_mcontext.arm_fp;
 588         sp = uc->uc_mcontext.arm_sp;
 589         if (sp < 0x1000)
 590             sp = 0x1000;
 591 #else
 592         return -1;
 593 #endif
 594         /* XXX: specific to tinycc stack frames */
 595         if (fp < sp + 12 || fp & 3)
 596             return -1;
 597         for(i = 1; i < level; i++) {
 598             sp = ((addr_t *)fp)[-2];
 599             if (sp < fp || sp - fp > 16 || sp & 3)
 600                 return -1;
 601             fp = ((addr_t *)fp)[-3];
 602             if (fp <= sp || fp - sp < 12 || fp & 3)
 603                 return -1;
 604         }
 605         /* XXX: check address validity with program info */
 606         *paddr = ((addr_t *)fp)[-1];
 607         return 0;
 608     }
 609 }
 610
 611 /* ------------------------------------------------------------- */
 612 #elif defined(__aarch64__)
 613
 614 static int rt_get_caller_pc(addr_t *paddr, ucontext_t *uc, int level)
 615 {
 616     if (level < 0)
 617         return -1;
 618     else if (level == 0) {
 619         *paddr = uc->uc_mcontext.pc;
 620         return 0;
 621     }
 622     else {
 623         addr_t *fp = (addr_t *)uc->uc_mcontext.regs[29];
 624         int i;
 625         for (i = 1; i < level; i++)
 626             fp = (addr_t *)fp[0];
 627         *paddr = fp[1];
 628         return 0;
 629     }
 630 }
 631
 632 /* ------------------------------------------------------------- */
 633 #else
 634
 635 #warning add arch specific rt_get_caller_pc()
 636 static int rt_get_caller_pc(addr_t *paddr, ucontext_t *uc, int level)
 637 {
 638     return -1;
 639 }
 640
 641 #endif /* !__i386__ */
 642
 643 /* ------------------------------------------------------------- */
 644 #else /* WIN32 */
 645
 646 static long __stdcall cpu_exception_handler(EXCEPTION_POINTERS *ex_info)
 647 {
 648     EXCEPTION_RECORD *er = ex_info->ExceptionRecord;
 649     CONTEXT *uc = ex_info->ContextRecord;
 650     switch (er->ExceptionCode) {
 651     case EXCEPTION_ACCESS_VIOLATION:
 652         if (rt_bound_error_msg && *rt_bound_error_msg)
 653             rt_error(uc, *rt_bound_error_msg);
 654         else
 655             rt_error(uc, "access violation");
 656         break;
 657     case EXCEPTION_STACK_OVERFLOW:
 658         rt_error(uc, "stack overflow");
 659         break;
 660     case EXCEPTION_INT_DIVIDE_BY_ZERO:
 661         rt_error(uc, "division by zero");
 662         break;
 663     default:
 664         rt_error(uc, "exception caught");
 665         break;
 666     }
 667     return EXCEPTION_EXECUTE_HANDLER;
 668 }
 669
 670 /* Generate a stack backtrace when a CPU exception occurs. */
 671 static void set_exception_handler(void)
 672 {
 673     SetUnhandledExceptionFilter(cpu_exception_handler);
 674 }
 675
 676 #ifdef _WIN64
 677 static void win64_add_function_table(TCCState *s1)
 678 {
 679     RtlAddFunctionTable(
 680         (RUNTIME_FUNCTION*)s1->uw_pdata->sh_addr,
 681         s1->uw_pdata->data_offset / sizeof (RUNTIME_FUNCTION),
 682         text_section->sh_addr
 683         );
 684 }
 685 #endif
 686
 687 /* return the PC at frame level 'level'. Return non zero if not found */
 688 static int rt_get_caller_pc(addr_t *paddr, CONTEXT *uc, int level)
 689 {
 690     addr_t fp, pc;
 691     int i;
 692 #ifdef _WIN64
 693     pc = uc->Rip;
 694     fp = uc->Rbp;
 695 #else
 696     pc = uc->Eip;
 697     fp = uc->Ebp;
 698 #endif
 699     if (level > 0) {
 700         for(i=1;i<level;i++) {
 701             /* XXX: check address validity with program info */
 702             if (fp <= 0x1000 || fp >= 0xc0000000)
 703                 return -1;
 704             fp = ((addr_t*)fp)[0];
 705         }
 706         pc = ((addr_t*)fp)[1];
 707     }
 708     *paddr = pc;
 709     return 0;
 710 }
 711
 712 #endif /* _WIN32 */
 713 #endif /* CONFIG_TCC_BACKTRACE */
 714 /* ------------------------------------------------------------- */
 715 #ifdef CONFIG_TCC_STATIC
 716
 717 /* dummy function for profiling */
 718 ST_FUNC void *dlopen(const char *filename, int flag)
 719 {
 720     return NULL;
 721 }
 722
 723 ST_FUNC void dlclose(void *p)
 724 {
 725 }
 726
 727 ST_FUNC const char *dlerror(void)
 728 {
 729     return "error";
 730 }
 731
 732 typedef struct TCCSyms {
 733     char *str;
 734     void *ptr;
 735 } TCCSyms;
 736
 737
 738 /* add the symbol you want here if no dynamic linking is done */
 739 static TCCSyms tcc_syms[] = {
 740 #if !defined(CONFIG_TCCBOOT)
 741 #define TCCSYM(a) { #a, &a, },
 742     TCCSYM(printf)
 743     TCCSYM(fprintf)
 744     TCCSYM(fopen)
 745     TCCSYM(fclose)
 746 #undef TCCSYM
 747 #endif
 748     { NULL, NULL },
 749 };
 750
 751 ST_FUNC void *dlsym(int flag, const char *symbol)
 752 {
 753     TCCSyms *p;
 754     p = tcc_syms;
 755     while (p->str != NULL) {
 756         if (!strcmp(p->str, symbol))
 757             return p->ptr;
 758         p++;
 759     }
 760     return NULL;
 761 }
 762
 763 #endif /* CONFIG_TCC_STATIC */
 764 #endif /* TCC_IS_NATIVE */
 765 /* ------------------------------------------------------------- */