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Annotation of OpenXM_contrib2/asir2000/gc/os_dep.c, Revision 1.1.1.1

1.1       noro        1: int ox_usr1_sent, ox_int_received, critical_when_signal;
                      2: static int inside_critical_section;
                      3:
                      4: /*
                      5:  * Copyright (c) 1991-1995 by Xerox Corporation.  All rights reserved.
                      6:  * Copyright (c) 1996-1997 by Silicon Graphics.  All rights reserved.
                      7:  *
                      8:  * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
                      9:  * OR IMPLIED.  ANY USE IS AT YOUR OWN RISK.
                     10:  *
                     11:  * Permission is hereby granted to use or copy this program
                     12:  * for any purpose,  provided the above notices are retained on all copies.
                     13:  * Permission to modify the code and to distribute modified code is granted,
                     14:  * provided the above notices are retained, and a notice that the code was
                     15:  * modified is included with the above copyright notice.
                     16:  */
                     17:
                     18: # include "gc_priv.h"
                     19:
                     20: # if defined(LINUX) && !defined(POWERPC)
                     21: #   include <linux/version.h>
                     22: #   if (LINUX_VERSION_CODE <= 0x10400)
                     23:       /* Ugly hack to get struct sigcontext_struct definition.  Required      */
                     24:       /* for some early 1.3.X releases.  Will hopefully go away soon. */
                     25:       /* in some later Linux releases, asm/sigcontext.h may have to   */
                     26:       /* be included instead.                                         */
                     27: #     define __KERNEL__
                     28: #     include <asm/signal.h>
                     29: #     undef __KERNEL__
                     30: #   else
                     31:       /* Kernels prior to 2.1.1 defined struct sigcontext_struct instead of */
                     32:       /* struct sigcontext.  libc6 (glibc2) uses "struct sigcontext" in     */
                     33:       /* prototypes, so we have to include the top-level sigcontext.h to    */
                     34:       /* make sure the former gets defined to be the latter if appropriate. */
                     35: #     include <features.h>
                     36: #     if 2 <= __GLIBC__
                     37: #       if 0 == __GLIBC_MINOR__
                     38:          /* glibc 2.1 no longer has sigcontext.h.  But signal.h        */
                     39:          /* has the right declaration for glibc 2.1.                   */
                     40: #         include <sigcontext.h>
                     41: #       endif /* 0 == __GLIBC_MINOR__ */
                     42: #     else /* not 2 <= __GLIBC__ */
                     43:         /* libc5 doesn't have <sigcontext.h>: go directly with the kernel   */
                     44:         /* one.  Check LINUX_VERSION_CODE to see which we should reference. */
                     45: #       include <asm/sigcontext.h>
                     46: #     endif /* 2 <= __GLIBC__ */
                     47: #   endif
                     48: # endif
                     49: # if !defined(OS2) && !defined(PCR) && !defined(AMIGA) && !defined(MACOS)
                     50: #   include <sys/types.h>
                     51: #   if !defined(MSWIN32) && !defined(SUNOS4)
                     52: #      include <unistd.h>
                     53: #   endif
                     54: # endif
                     55:
                     56: # include <stdio.h>
                     57: # include <signal.h>
                     58:
                     59: /* Blatantly OS dependent routines, except for those that are related  */
                     60: /* dynamic loading.                                                    */
                     61:
                     62: # if !defined(THREADS) && !defined(STACKBOTTOM) && defined(HEURISTIC2)
                     63: #   define NEED_FIND_LIMIT
                     64: # endif
                     65:
                     66: # if defined(IRIX_THREADS)
                     67: #   define NEED_FIND_LIMIT
                     68: # endif
                     69:
                     70: # if (defined(SUNOS4) & defined(DYNAMIC_LOADING)) && !defined(PCR)
                     71: #   define NEED_FIND_LIMIT
                     72: # endif
                     73:
                     74: # if (defined(SVR4) || defined(AUX) || defined(DGUX)) && !defined(PCR)
                     75: #   define NEED_FIND_LIMIT
                     76: # endif
                     77:
                     78: # if defined(LINUX) && (defined(POWERPC) || defined(SPARC) || defined(ALPHA))
                     79: #   define NEED_FIND_LIMIT
                     80: # endif
                     81:
                     82: #ifdef NEED_FIND_LIMIT
                     83: #   include <setjmp.h>
                     84: #endif
                     85:
                     86: #ifdef FREEBSD
                     87: #  include <machine/trap.h>
                     88: #endif
                     89:
                     90: #ifdef AMIGA
                     91: # include <proto/exec.h>
                     92: # include <proto/dos.h>
                     93: # include <dos/dosextens.h>
                     94: # include <workbench/startup.h>
                     95: #endif
                     96:
                     97: #ifdef MSWIN32
                     98: # define WIN32_LEAN_AND_MEAN
                     99: # define NOSERVICE
                    100: # include <windows.h>
                    101: #endif
                    102:
                    103: #ifdef MACOS
                    104: # include <Processes.h>
                    105: #endif
                    106:
                    107: #ifdef IRIX5
                    108: # include <sys/uio.h>
                    109: # include <malloc.h>   /* for locking */
                    110: #endif
                    111: #ifdef USE_MMAP
                    112: # include <sys/types.h>
                    113: # include <sys/mman.h>
                    114: # include <sys/stat.h>
                    115: # include <fcntl.h>
                    116: #endif
                    117:
                    118: #ifdef SUNOS5SIGS
                    119: # include <sys/siginfo.h>
                    120: # undef setjmp
                    121: # undef longjmp
                    122: # define setjmp(env) sigsetjmp(env, 1)
                    123: # define longjmp(env, val) siglongjmp(env, val)
                    124: # define jmp_buf sigjmp_buf
                    125: #endif
                    126:
                    127: #ifdef DJGPP
                    128:   /* Apparently necessary for djgpp 2.01.  May casuse problems with    */
                    129:   /* other versions.                                                   */
                    130:   typedef long unsigned int caddr_t;
                    131: #endif
                    132:
                    133: #ifdef PCR
                    134: # include "il/PCR_IL.h"
                    135: # include "th/PCR_ThCtl.h"
                    136: # include "mm/PCR_MM.h"
                    137: #endif
                    138:
                    139: #if !defined(NO_EXECUTE_PERMISSION)
                    140: # define OPT_PROT_EXEC PROT_EXEC
                    141: #else
                    142: # define OPT_PROT_EXEC 0
                    143: #endif
                    144:
                    145: #if defined(LINUX) && (defined(POWERPC) || defined(SPARC) || defined(ALPHA))
                    146:   /* The I386 case can be handled without a search.  The Alpha case    */
                    147:   /* used to be handled differently as well, but the rules changed     */
                    148:   /* for recent Linux versions.  This seems to be the easiest way to   */
                    149:   /* cover all versions.                                               */
                    150:   ptr_t GC_data_start;
                    151:
                    152:   extern char * GC_copyright[];  /* Any data symbol would do. */
                    153:
                    154:   void GC_init_linux_data_start()
                    155:   {
                    156:     extern ptr_t GC_find_limit();
                    157:
                    158:     GC_data_start = GC_find_limit((ptr_t)GC_copyright, FALSE);
                    159:   }
                    160: #endif
                    161:
                    162: # ifdef OS2
                    163:
                    164: # include <stddef.h>
                    165:
                    166: # if !defined(__IBMC__) && !defined(__WATCOMC__) /* e.g. EMX */
                    167:
                    168: struct exe_hdr {
                    169:     unsigned short      magic_number;
                    170:     unsigned short      padding[29];
                    171:     long                new_exe_offset;
                    172: };
                    173:
                    174: #define E_MAGIC(x)      (x).magic_number
                    175: #define EMAGIC          0x5A4D
                    176: #define E_LFANEW(x)     (x).new_exe_offset
                    177:
                    178: struct e32_exe {
                    179:     unsigned char       magic_number[2];
                    180:     unsigned char       byte_order;
                    181:     unsigned char       word_order;
                    182:     unsigned long       exe_format_level;
                    183:     unsigned short      cpu;
                    184:     unsigned short      os;
                    185:     unsigned long       padding1[13];
                    186:     unsigned long       object_table_offset;
                    187:     unsigned long       object_count;
                    188:     unsigned long       padding2[31];
                    189: };
                    190:
                    191: #define E32_MAGIC1(x)   (x).magic_number[0]
                    192: #define E32MAGIC1       'L'
                    193: #define E32_MAGIC2(x)   (x).magic_number[1]
                    194: #define E32MAGIC2       'X'
                    195: #define E32_BORDER(x)   (x).byte_order
                    196: #define E32LEBO         0
                    197: #define E32_WORDER(x)   (x).word_order
                    198: #define E32LEWO         0
                    199: #define E32_CPU(x)      (x).cpu
                    200: #define E32CPU286       1
                    201: #define E32_OBJTAB(x)   (x).object_table_offset
                    202: #define E32_OBJCNT(x)   (x).object_count
                    203:
                    204: struct o32_obj {
                    205:     unsigned long       size;
                    206:     unsigned long       base;
                    207:     unsigned long       flags;
                    208:     unsigned long       pagemap;
                    209:     unsigned long       mapsize;
                    210:     unsigned long       reserved;
                    211: };
                    212:
                    213: #define O32_FLAGS(x)    (x).flags
                    214: #define OBJREAD         0x0001L
                    215: #define OBJWRITE        0x0002L
                    216: #define OBJINVALID      0x0080L
                    217: #define O32_SIZE(x)     (x).size
                    218: #define O32_BASE(x)     (x).base
                    219:
                    220: # else  /* IBM's compiler */
                    221:
                    222: /* A kludge to get around what appears to be a header file bug */
                    223: # ifndef WORD
                    224: #   define WORD unsigned short
                    225: # endif
                    226: # ifndef DWORD
                    227: #   define DWORD unsigned long
                    228: # endif
                    229:
                    230: # define EXE386 1
                    231: # include <newexe.h>
                    232: # include <exe386.h>
                    233:
                    234: # endif  /* __IBMC__ */
                    235:
                    236: # define INCL_DOSEXCEPTIONS
                    237: # define INCL_DOSPROCESS
                    238: # define INCL_DOSERRORS
                    239: # define INCL_DOSMODULEMGR
                    240: # define INCL_DOSMEMMGR
                    241: # include <os2.h>
                    242:
                    243:
                    244: /* Disable and enable signals during nontrivial allocations    */
                    245:
                    246: void GC_disable_signals(void)
                    247: {
                    248:     ULONG nest;
                    249:
                    250:     DosEnterMustComplete(&nest);
                    251:     if (nest != 1) ABORT("nested GC_disable_signals");
                    252: }
                    253:
                    254: void GC_enable_signals(void)
                    255: {
                    256:     ULONG nest;
                    257:
                    258:     DosExitMustComplete(&nest);
                    259:     if (nest != 0) ABORT("GC_enable_signals");
                    260: }
                    261:
                    262:
                    263: # else
                    264:
                    265: #  if !defined(PCR) && !defined(AMIGA) && !defined(MSWIN32) \
                    266:       && !defined(MACOS) && !defined(DJGPP) && !defined(DOS4GW)
                    267:
                    268: #   if defined(sigmask) && !defined(UTS4)
                    269:        /* Use the traditional BSD interface */
                    270: #      define SIGSET_T int
                    271: #      define SIG_DEL(set, signal) (set) &= ~(sigmask(signal))
                    272: #      define SIG_FILL(set)  (set) = 0x7fffffff
                    273:          /* Setting the leading bit appears to provoke a bug in some   */
                    274:          /* longjmp implementations.  Most systems appear not to have  */
                    275:          /* a signal 32.                                               */
                    276: #      define SIGSETMASK(old, new) (old) = sigsetmask(new)
                    277: #   else
                    278:        /* Use POSIX/SYSV interface     */
                    279: #      define SIGSET_T sigset_t
                    280: #      define SIG_DEL(set, signal) sigdelset(&(set), (signal))
                    281: #      define SIG_FILL(set) sigfillset(&set)
                    282: #      define SIGSETMASK(old, new) sigprocmask(SIG_SETMASK, &(new), &(old))
                    283: #   endif
                    284:
                    285: static GC_bool mask_initialized = FALSE;
                    286:
                    287: static SIGSET_T new_mask;
                    288:
                    289: static SIGSET_T old_mask;
                    290:
                    291: static SIGSET_T dummy;
                    292:
                    293: #if defined(PRINTSTATS) && !defined(THREADS)
                    294: # define CHECK_SIGNALS
                    295:   int GC_sig_disabled = 0;
                    296: #endif
                    297:
                    298: void GC_disable_signals()
                    299: {
                    300:     if (!mask_initialized) {
                    301:        SIG_FILL(new_mask);
                    302:
                    303:        SIG_DEL(new_mask, SIGSEGV);
                    304:        SIG_DEL(new_mask, SIGILL);
                    305:        SIG_DEL(new_mask, SIGQUIT);
                    306: #      ifdef SIGBUS
                    307:            SIG_DEL(new_mask, SIGBUS);
                    308: #      endif
                    309: #      ifdef SIGIOT
                    310:            SIG_DEL(new_mask, SIGIOT);
                    311: #      endif
                    312: #      ifdef SIGEMT
                    313:            SIG_DEL(new_mask, SIGEMT);
                    314: #      endif
                    315: #      ifdef SIGTRAP
                    316:            SIG_DEL(new_mask, SIGTRAP);
                    317: #      endif
                    318:        mask_initialized = TRUE;
                    319:     }
                    320: #   ifdef CHECK_SIGNALS
                    321:        if (GC_sig_disabled != 0) ABORT("Nested disables");
                    322:        GC_sig_disabled++;
                    323: #   endif
                    324:     SIGSETMASK(old_mask,new_mask);
                    325:        if ( critical_when_signal )
                    326:                inside_critical_section = 1;
                    327:        else {
                    328:                inside_critical_section = 0;
                    329:                critical_when_signal = 1;
                    330:        }
                    331: }
                    332:
                    333: void GC_enable_signals()
                    334: {
                    335: #   ifdef CHECK_SIGNALS
                    336:        if (GC_sig_disabled != 1) ABORT("Unmatched enable");
                    337:        GC_sig_disabled--;
                    338: #   endif
                    339:     SIGSETMASK(dummy,old_mask);
                    340:        if ( !inside_critical_section ) {
                    341:                critical_when_signal = 0;
                    342:                if ( ox_usr1_sent ) {
                    343:                        ox_usr1_sent = 0; ox_usr1_handler();
                    344:                }
                    345:                if ( ox_int_received ) {
                    346:                        ox_int_received = 0; int_handler();
                    347:                }
                    348:        } else
                    349:                inside_critical_section = 0;
                    350: }
                    351:
                    352: #  endif  /* !PCR */
                    353:
                    354: # endif /*!OS/2 */
                    355:
                    356: /* Ivan Demakov: simplest way (to me) */
                    357: #ifdef DOS4GW
                    358:   void GC_disable_signals() { }
                    359:   void GC_enable_signals() { }
                    360: #endif
                    361:
                    362: /* Find the page size */
                    363: word GC_page_size;
                    364:
                    365: # ifdef MSWIN32
                    366:   void GC_setpagesize()
                    367:   {
                    368:     SYSTEM_INFO sysinfo;
                    369:
                    370:     GetSystemInfo(&sysinfo);
                    371:     GC_page_size = sysinfo.dwPageSize;
                    372:   }
                    373:
                    374: # else
                    375: #   if defined(MPROTECT_VDB) || defined(PROC_VDB) || defined(USE_MMAP) \
                    376:        || defined(USE_MUNMAP)
                    377:        void GC_setpagesize()
                    378:        {
                    379:            GC_page_size = GETPAGESIZE();
                    380:        }
                    381: #   else
                    382:        /* It's acceptable to fake it. */
                    383:        void GC_setpagesize()
                    384:        {
                    385:            GC_page_size = HBLKSIZE;
                    386:        }
                    387: #   endif
                    388: # endif
                    389:
                    390: /*
                    391:  * Find the base of the stack.
                    392:  * Used only in single-threaded environment.
                    393:  * With threads, GC_mark_roots needs to know how to do this.
                    394:  * Called with allocator lock held.
                    395:  */
                    396: # ifdef MSWIN32
                    397: # define is_writable(prot) ((prot) == PAGE_READWRITE \
                    398:                            || (prot) == PAGE_WRITECOPY \
                    399:                            || (prot) == PAGE_EXECUTE_READWRITE \
                    400:                            || (prot) == PAGE_EXECUTE_WRITECOPY)
                    401: /* Return the number of bytes that are writable starting at p. */
                    402: /* The pointer p is assumed to be page aligned.                        */
                    403: /* If base is not 0, *base becomes the beginning of the        */
                    404: /* allocation region containing p.                             */
                    405: word GC_get_writable_length(ptr_t p, ptr_t *base)
                    406: {
                    407:     MEMORY_BASIC_INFORMATION buf;
                    408:     word result;
                    409:     word protect;
                    410:
                    411:     result = VirtualQuery(p, &buf, sizeof(buf));
                    412:     if (result != sizeof(buf)) ABORT("Weird VirtualQuery result");
                    413:     if (base != 0) *base = (ptr_t)(buf.AllocationBase);
                    414:     protect = (buf.Protect & ~(PAGE_GUARD | PAGE_NOCACHE));
                    415:     if (!is_writable(protect)) {
                    416:         return(0);
                    417:     }
                    418:     if (buf.State != MEM_COMMIT) return(0);
                    419:     return(buf.RegionSize);
                    420: }
                    421:
                    422: ptr_t GC_get_stack_base()
                    423: {
                    424:     int dummy;
                    425:     ptr_t sp = (ptr_t)(&dummy);
                    426:     ptr_t trunc_sp = (ptr_t)((word)sp & ~(GC_page_size - 1));
                    427:     word size = GC_get_writable_length(trunc_sp, 0);
                    428:
                    429:     return(trunc_sp + size);
                    430: }
                    431:
                    432:
                    433: # else
                    434:
                    435: # ifdef OS2
                    436:
                    437: ptr_t GC_get_stack_base()
                    438: {
                    439:     PTIB ptib;
                    440:     PPIB ppib;
                    441:
                    442:     if (DosGetInfoBlocks(&ptib, &ppib) != NO_ERROR) {
                    443:        GC_err_printf0("DosGetInfoBlocks failed\n");
                    444:        ABORT("DosGetInfoBlocks failed\n");
                    445:     }
                    446:     return((ptr_t)(ptib -> tib_pstacklimit));
                    447: }
                    448:
                    449: # else
                    450:
                    451: # ifdef AMIGA
                    452:
                    453: ptr_t GC_get_stack_base()
                    454: {
                    455:     struct Process *proc = (struct Process*)SysBase->ThisTask;
                    456:
                    457:     /* Reference: Amiga Guru Book Pages: 42,567,574 */
                    458:     if (proc->pr_Task.tc_Node.ln_Type==NT_PROCESS
                    459:         && proc->pr_CLI != NULL) {
                    460:        /* first ULONG is StackSize */
                    461:        /*longPtr = proc->pr_ReturnAddr;
                    462:        size = longPtr[0];*/
                    463:
                    464:        return (char *)proc->pr_ReturnAddr + sizeof(ULONG);
                    465:     } else {
                    466:        return (char *)proc->pr_Task.tc_SPUpper;
                    467:     }
                    468: }
                    469:
                    470: #if 0 /* old version */
                    471: ptr_t GC_get_stack_base()
                    472: {
                    473:     extern struct WBStartup *_WBenchMsg;
                    474:     extern long __base;
                    475:     extern long __stack;
                    476:     struct Task *task;
                    477:     struct Process *proc;
                    478:     struct CommandLineInterface *cli;
                    479:     long size;
                    480:
                    481:     if ((task = FindTask(0)) == 0) {
                    482:        GC_err_puts("Cannot find own task structure\n");
                    483:        ABORT("task missing");
                    484:     }
                    485:     proc = (struct Process *)task;
                    486:     cli = BADDR(proc->pr_CLI);
                    487:
                    488:     if (_WBenchMsg != 0 || cli == 0) {
                    489:        size = (char *)task->tc_SPUpper - (char *)task->tc_SPLower;
                    490:     } else {
                    491:        size = cli->cli_DefaultStack * 4;
                    492:     }
                    493:     return (ptr_t)(__base + GC_max(size, __stack));
                    494: }
                    495: #endif /* 0 */
                    496:
                    497: # else /* !AMIGA, !OS2, ... */
                    498:
                    499: # ifdef NEED_FIND_LIMIT
                    500:   /* Some tools to implement HEURISTIC2        */
                    501: #   define MIN_PAGE_SIZE 256   /* Smallest conceivable page size, bytes */
                    502:     /* static */ jmp_buf GC_jmp_buf;
                    503:
                    504:     /*ARGSUSED*/
                    505:     void GC_fault_handler(sig)
                    506:     int sig;
                    507:     {
                    508:         longjmp(GC_jmp_buf, 1);
                    509:     }
                    510:
                    511: #   ifdef __STDC__
                    512:        typedef void (*handler)(int);
                    513: #   else
                    514:        typedef void (*handler)();
                    515: #   endif
                    516:
                    517: #   if defined(SUNOS5SIGS) || defined(IRIX5) || defined(OSF1)
                    518:        static struct sigaction old_segv_act;
                    519: #      if defined(_sigargs) /* !Irix6.x */
                    520:            static struct sigaction old_bus_act;
                    521: #      endif
                    522: #   else
                    523:         static handler old_segv_handler, old_bus_handler;
                    524: #   endif
                    525:
                    526:     void GC_setup_temporary_fault_handler()
                    527:     {
                    528: #      if defined(SUNOS5SIGS) || defined(IRIX5) || defined(OSF1)
                    529:          struct sigaction      act;
                    530:
                    531:          act.sa_handler        = GC_fault_handler;
                    532:           act.sa_flags          = SA_RESTART | SA_NODEFER;
                    533:           /* The presence of SA_NODEFER represents yet another gross    */
                    534:           /* hack.  Under Solaris 2.3, siglongjmp doesn't appear to     */
                    535:           /* interact correctly with -lthread.  We hide the confusion   */
                    536:           /* by making sure that signal handling doesn't affect the     */
                    537:           /* signal mask.                                               */
                    538:
                    539:          (void) sigemptyset(&act.sa_mask);
                    540: #        ifdef IRIX_THREADS
                    541:                /* Older versions have a bug related to retrieving and  */
                    542:                /* and setting a handler at the same time.              */
                    543:                (void) sigaction(SIGSEGV, 0, &old_segv_act);
                    544:                (void) sigaction(SIGSEGV, &act, 0);
                    545: #        else
                    546:                (void) sigaction(SIGSEGV, &act, &old_segv_act);
                    547: #              ifdef _sigargs  /* Irix 5.x, not 6.x */
                    548:                    /* Under 5.x, we may get SIGBUS.                    */
                    549:                    /* Pthreads doesn't exist under 5.x, so we don't    */
                    550:                    /* have to worry in the threads case.               */
                    551:                    (void) sigaction(SIGBUS, &act, &old_bus_act);
                    552: #              endif
                    553: #        endif /* IRIX_THREADS */
                    554: #      else
                    555:          old_segv_handler = signal(SIGSEGV, GC_fault_handler);
                    556: #        ifdef SIGBUS
                    557:            old_bus_handler = signal(SIGBUS, GC_fault_handler);
                    558: #        endif
                    559: #      endif
                    560:     }
                    561:
                    562:     void GC_reset_fault_handler()
                    563:     {
                    564: #       if defined(SUNOS5SIGS) || defined(IRIX5) || defined(OSF1)
                    565:          (void) sigaction(SIGSEGV, &old_segv_act, 0);
                    566: #        ifdef _sigargs        /* Irix 5.x, not 6.x */
                    567:              (void) sigaction(SIGBUS, &old_bus_act, 0);
                    568: #        endif
                    569: #       else
                    570:          (void) signal(SIGSEGV, old_segv_handler);
                    571: #        ifdef SIGBUS
                    572:            (void) signal(SIGBUS, old_bus_handler);
                    573: #        endif
                    574: #       endif
                    575:     }
                    576:
                    577:     /* Return the first nonaddressible location > p (up) or    */
                    578:     /* the smallest location q s.t. [q,p] is addressible (!up).        */
                    579:     ptr_t GC_find_limit(p, up)
                    580:     ptr_t p;
                    581:     GC_bool up;
                    582:     {
                    583:         static VOLATILE ptr_t result;
                    584:                /* Needs to be static, since otherwise it may not be    */
                    585:                /* preserved across the longjmp.  Can safely be         */
                    586:                /* static since it's only called once, with the         */
                    587:                /* allocation lock held.                                */
                    588:
                    589:
                    590:        GC_setup_temporary_fault_handler();
                    591:        if (setjmp(GC_jmp_buf) == 0) {
                    592:            result = (ptr_t)(((word)(p))
                    593:                              & ~(MIN_PAGE_SIZE-1));
                    594:            for (;;) {
                    595:                if (up) {
                    596:                    result += MIN_PAGE_SIZE;
                    597:                } else {
                    598:                    result -= MIN_PAGE_SIZE;
                    599:                }
                    600:                GC_noop1((word)(*result));
                    601:            }
                    602:        }
                    603:        GC_reset_fault_handler();
                    604:        if (!up) {
                    605:            result += MIN_PAGE_SIZE;
                    606:        }
                    607:        return(result);
                    608:     }
                    609: # endif
                    610:
                    611:
                    612: ptr_t GC_get_stack_base()
                    613: {
                    614:     word dummy;
                    615:     ptr_t result;
                    616:
                    617: #   define STACKBOTTOM_ALIGNMENT_M1 ((word)STACK_GRAN - 1)
                    618:
                    619: #   ifdef STACKBOTTOM
                    620:        return(STACKBOTTOM);
                    621: #   else
                    622: #      ifdef HEURISTIC1
                    623: #         ifdef STACK_GROWS_DOWN
                    624:             result = (ptr_t)((((word)(&dummy))
                    625:                               + STACKBOTTOM_ALIGNMENT_M1)
                    626:                              & ~STACKBOTTOM_ALIGNMENT_M1);
                    627: #         else
                    628:             result = (ptr_t)(((word)(&dummy))
                    629:                              & ~STACKBOTTOM_ALIGNMENT_M1);
                    630: #         endif
                    631: #      endif /* HEURISTIC1 */
                    632: #      ifdef HEURISTIC2
                    633: #          ifdef STACK_GROWS_DOWN
                    634:                result = GC_find_limit((ptr_t)(&dummy), TRUE);
                    635: #              ifdef HEURISTIC2_LIMIT
                    636:                    if (result > HEURISTIC2_LIMIT
                    637:                        && (ptr_t)(&dummy) < HEURISTIC2_LIMIT) {
                    638:                            result = HEURISTIC2_LIMIT;
                    639:                    }
                    640: #              endif
                    641: #          else
                    642:                result = GC_find_limit((ptr_t)(&dummy), FALSE);
                    643: #              ifdef HEURISTIC2_LIMIT
                    644:                    if (result < HEURISTIC2_LIMIT
                    645:                        && (ptr_t)(&dummy) > HEURISTIC2_LIMIT) {
                    646:                            result = HEURISTIC2_LIMIT;
                    647:                    }
                    648: #              endif
                    649: #          endif
                    650:
                    651: #      endif /* HEURISTIC2 */
                    652: #      ifdef STACK_GROWS_DOWN
                    653:            if (result == 0) result = (ptr_t)(signed_word)(-sizeof(ptr_t));
                    654: #      endif
                    655:        return(result);
                    656: #   endif /* STACKBOTTOM */
                    657: }
                    658:
                    659: # endif /* ! AMIGA */
                    660: # endif /* ! OS2 */
                    661: # endif /* ! MSWIN32 */
                    662:
                    663: /*
                    664:  * Register static data segment(s) as roots.
                    665:  * If more data segments are added later then they need to be registered
                    666:  * add that point (as we do with SunOS dynamic loading),
                    667:  * or GC_mark_roots needs to check for them (as we do with PCR).
                    668:  * Called with allocator lock held.
                    669:  */
                    670:
                    671: # ifdef OS2
                    672:
                    673: void GC_register_data_segments()
                    674: {
                    675:     PTIB ptib;
                    676:     PPIB ppib;
                    677:     HMODULE module_handle;
                    678: #   define PBUFSIZ 512
                    679:     UCHAR path[PBUFSIZ];
                    680:     FILE * myexefile;
                    681:     struct exe_hdr hdrdos;     /* MSDOS header.        */
                    682:     struct e32_exe hdr386;     /* Real header for my executable */
                    683:     struct o32_obj seg;        /* Currrent segment */
                    684:     int nsegs;
                    685:
                    686:
                    687:     if (DosGetInfoBlocks(&ptib, &ppib) != NO_ERROR) {
                    688:        GC_err_printf0("DosGetInfoBlocks failed\n");
                    689:        ABORT("DosGetInfoBlocks failed\n");
                    690:     }
                    691:     module_handle = ppib -> pib_hmte;
                    692:     if (DosQueryModuleName(module_handle, PBUFSIZ, path) != NO_ERROR) {
                    693:        GC_err_printf0("DosQueryModuleName failed\n");
                    694:        ABORT("DosGetInfoBlocks failed\n");
                    695:     }
                    696:     myexefile = fopen(path, "rb");
                    697:     if (myexefile == 0) {
                    698:         GC_err_puts("Couldn't open executable ");
                    699:         GC_err_puts(path); GC_err_puts("\n");
                    700:         ABORT("Failed to open executable\n");
                    701:     }
                    702:     if (fread((char *)(&hdrdos), 1, sizeof hdrdos, myexefile) < sizeof hdrdos) {
                    703:         GC_err_puts("Couldn't read MSDOS header from ");
                    704:         GC_err_puts(path); GC_err_puts("\n");
                    705:         ABORT("Couldn't read MSDOS header");
                    706:     }
                    707:     if (E_MAGIC(hdrdos) != EMAGIC) {
                    708:         GC_err_puts("Executable has wrong DOS magic number: ");
                    709:         GC_err_puts(path); GC_err_puts("\n");
                    710:         ABORT("Bad DOS magic number");
                    711:     }
                    712:     if (fseek(myexefile, E_LFANEW(hdrdos), SEEK_SET) != 0) {
                    713:         GC_err_puts("Seek to new header failed in ");
                    714:         GC_err_puts(path); GC_err_puts("\n");
                    715:         ABORT("Bad DOS magic number");
                    716:     }
                    717:     if (fread((char *)(&hdr386), 1, sizeof hdr386, myexefile) < sizeof hdr386) {
                    718:         GC_err_puts("Couldn't read MSDOS header from ");
                    719:         GC_err_puts(path); GC_err_puts("\n");
                    720:         ABORT("Couldn't read OS/2 header");
                    721:     }
                    722:     if (E32_MAGIC1(hdr386) != E32MAGIC1 || E32_MAGIC2(hdr386) != E32MAGIC2) {
                    723:         GC_err_puts("Executable has wrong OS/2 magic number:");
                    724:         GC_err_puts(path); GC_err_puts("\n");
                    725:         ABORT("Bad OS/2 magic number");
                    726:     }
                    727:     if ( E32_BORDER(hdr386) != E32LEBO || E32_WORDER(hdr386) != E32LEWO) {
                    728:         GC_err_puts("Executable %s has wrong byte order: ");
                    729:         GC_err_puts(path); GC_err_puts("\n");
                    730:         ABORT("Bad byte order");
                    731:     }
                    732:     if ( E32_CPU(hdr386) == E32CPU286) {
                    733:         GC_err_puts("GC can't handle 80286 executables: ");
                    734:         GC_err_puts(path); GC_err_puts("\n");
                    735:         EXIT();
                    736:     }
                    737:     if (fseek(myexefile, E_LFANEW(hdrdos) + E32_OBJTAB(hdr386),
                    738:              SEEK_SET) != 0) {
                    739:         GC_err_puts("Seek to object table failed: ");
                    740:         GC_err_puts(path); GC_err_puts("\n");
                    741:         ABORT("Seek to object table failed");
                    742:     }
                    743:     for (nsegs = E32_OBJCNT(hdr386); nsegs > 0; nsegs--) {
                    744:       int flags;
                    745:       if (fread((char *)(&seg), 1, sizeof seg, myexefile) < sizeof seg) {
                    746:         GC_err_puts("Couldn't read obj table entry from ");
                    747:         GC_err_puts(path); GC_err_puts("\n");
                    748:         ABORT("Couldn't read obj table entry");
                    749:       }
                    750:       flags = O32_FLAGS(seg);
                    751:       if (!(flags & OBJWRITE)) continue;
                    752:       if (!(flags & OBJREAD)) continue;
                    753:       if (flags & OBJINVALID) {
                    754:           GC_err_printf0("Object with invalid pages?\n");
                    755:           continue;
                    756:       }
                    757:       GC_add_roots_inner(O32_BASE(seg), O32_BASE(seg)+O32_SIZE(seg), FALSE);
                    758:     }
                    759: }
                    760:
                    761: # else
                    762:
                    763: # ifdef MSWIN32
                    764:   /* Unfortunately, we have to handle win32s very differently from NT,         */
                    765:   /* Since VirtualQuery has very different semantics.  In particular,  */
                    766:   /* under win32s a VirtualQuery call on an unmapped page returns an   */
                    767:   /* invalid result.  Under GC_register_data_segments is a noop and    */
                    768:   /* all real work is done by GC_register_dynamic_libraries.  Under    */
                    769:   /* win32s, we cannot find the data segments associated with dll's.   */
                    770:   /* We rgister the main data segment here.                            */
                    771:   GC_bool GC_win32s = FALSE;   /* We're running under win32s.  */
                    772:
                    773:   GC_bool GC_is_win32s()
                    774:   {
                    775:       DWORD v = GetVersion();
                    776:
                    777:       /* Check that this is not NT, and Windows major version <= 3     */
                    778:       return ((v & 0x80000000) && (v & 0xff) <= 3);
                    779:   }
                    780:
                    781:   void GC_init_win32()
                    782:   {
                    783:       GC_win32s = GC_is_win32s();
                    784:   }
                    785:
                    786:   /* Return the smallest address a such that VirtualQuery              */
                    787:   /* returns correct results for all addresses between a and start.    */
                    788:   /* Assumes VirtualQuery returns correct information for start.       */
                    789:   ptr_t GC_least_described_address(ptr_t start)
                    790:   {
                    791:     MEMORY_BASIC_INFORMATION buf;
                    792:     SYSTEM_INFO sysinfo;
                    793:     DWORD result;
                    794:     LPVOID limit;
                    795:     ptr_t p;
                    796:     LPVOID q;
                    797:
                    798:     GetSystemInfo(&sysinfo);
                    799:     limit = sysinfo.lpMinimumApplicationAddress;
                    800:     p = (ptr_t)((word)start & ~(GC_page_size - 1));
                    801:     for (;;) {
                    802:        q = (LPVOID)(p - GC_page_size);
                    803:        if ((ptr_t)q > (ptr_t)p /* underflow */ || q < limit) break;
                    804:        result = VirtualQuery(q, &buf, sizeof(buf));
                    805:        if (result != sizeof(buf) || buf.AllocationBase == 0) break;
                    806:        p = (ptr_t)(buf.AllocationBase);
                    807:     }
                    808:     return(p);
                    809:   }
                    810:
                    811:   /* Is p the start of either the malloc heap, or of one of our */
                    812:   /* heap sections?                                            */
                    813:   GC_bool GC_is_heap_base (ptr_t p)
                    814:   {
                    815:
                    816:      register unsigned i;
                    817:
                    818: #    ifndef REDIRECT_MALLOC
                    819:        static ptr_t malloc_heap_pointer = 0;
                    820:
                    821:        if (0 == malloc_heap_pointer) {
                    822:          MEMORY_BASIC_INFORMATION buf;
                    823:          register DWORD result = VirtualQuery(malloc(1), &buf, sizeof(buf));
                    824:
                    825:          if (result != sizeof(buf)) {
                    826:              ABORT("Weird VirtualQuery result");
                    827:          }
                    828:          malloc_heap_pointer = (ptr_t)(buf.AllocationBase);
                    829:        }
                    830:        if (p == malloc_heap_pointer) return(TRUE);
                    831: #    endif
                    832:      for (i = 0; i < GC_n_heap_bases; i++) {
                    833:          if (GC_heap_bases[i] == p) return(TRUE);
                    834:      }
                    835:      return(FALSE);
                    836:   }
                    837:
                    838:   void GC_register_root_section(ptr_t static_root)
                    839:   {
                    840:       MEMORY_BASIC_INFORMATION buf;
                    841:       SYSTEM_INFO sysinfo;
                    842:       DWORD result;
                    843:       DWORD protect;
                    844:       LPVOID p;
                    845:       char * base;
                    846:       char * limit, * new_limit;
                    847:
                    848:       if (!GC_win32s) return;
                    849:       p = base = limit = GC_least_described_address(static_root);
                    850:       GetSystemInfo(&sysinfo);
                    851:       while (p < sysinfo.lpMaximumApplicationAddress) {
                    852:         result = VirtualQuery(p, &buf, sizeof(buf));
                    853:         if (result != sizeof(buf) || buf.AllocationBase == 0
                    854:             || GC_is_heap_base(buf.AllocationBase)) break;
                    855:         new_limit = (char *)p + buf.RegionSize;
                    856:         protect = buf.Protect;
                    857:         if (buf.State == MEM_COMMIT
                    858:             && is_writable(protect)) {
                    859:             if ((char *)p == limit) {
                    860:                 limit = new_limit;
                    861:             } else {
                    862:                 if (base != limit) GC_add_roots_inner(base, limit, FALSE);
                    863:                 base = p;
                    864:                 limit = new_limit;
                    865:             }
                    866:         }
                    867:         if (p > (LPVOID)new_limit /* overflow */) break;
                    868:         p = (LPVOID)new_limit;
                    869:       }
                    870:       if (base != limit) GC_add_roots_inner(base, limit, FALSE);
                    871:   }
                    872:
                    873:   void GC_register_data_segments()
                    874:   {
                    875:       static char dummy;
                    876:
                    877:       GC_register_root_section((ptr_t)(&dummy));
                    878:   }
                    879: # else
                    880: # ifdef AMIGA
                    881:
                    882:    void GC_register_data_segments()
                    883:    {
                    884:      struct Process    *proc;
                    885:      struct CommandLineInterface *cli;
                    886:      BPTR myseglist;
                    887:      ULONG *data;
                    888:
                    889:      int       num;
                    890:
                    891:
                    892: #    ifdef __GNUC__
                    893:         ULONG dataSegSize;
                    894:         GC_bool found_segment = FALSE;
                    895:        extern char __data_size[];
                    896:
                    897:        dataSegSize=__data_size+8;
                    898:        /* Can`t find the Location of __data_size, because
                    899:            it`s possible that is it, inside the segment. */
                    900:
                    901: #     endif
                    902:
                    903:        proc= (struct Process*)SysBase->ThisTask;
                    904:
                    905:        /* Reference: Amiga Guru Book Pages: 538ff,565,573
                    906:                     and XOper.asm */
                    907:        if (proc->pr_Task.tc_Node.ln_Type==NT_PROCESS) {
                    908:          if (proc->pr_CLI == NULL) {
                    909:            myseglist = proc->pr_SegList;
                    910:          } else {
                    911:            /* ProcLoaded       'Loaded as a command: '*/
                    912:            cli = BADDR(proc->pr_CLI);
                    913:            myseglist = cli->cli_Module;
                    914:          }
                    915:        } else {
                    916:          ABORT("Not a Process.");
                    917:        }
                    918:
                    919:        if (myseglist == NULL) {
                    920:            ABORT("Arrrgh.. can't find segments, aborting");
                    921:        }
                    922:
                    923:        /* xoper hunks Shell Process */
                    924:
                    925:        num=0;
                    926:         for (data = (ULONG *)BADDR(myseglist); data != NULL;
                    927:              data = (ULONG *)BADDR(data[0])) {
                    928:          if (((ULONG) GC_register_data_segments < (ULONG) &data[1]) ||
                    929:              ((ULONG) GC_register_data_segments > (ULONG) &data[1] + data[-1])) {
                    930: #             ifdef __GNUC__
                    931:                if (dataSegSize == data[-1]) {
                    932:                  found_segment = TRUE;
                    933:                }
                    934: #            endif
                    935:              GC_add_roots_inner((char *)&data[1],
                    936:                                 ((char *)&data[1]) + data[-1], FALSE);
                    937:           }
                    938:           ++num;
                    939:         } /* for */
                    940: #      ifdef __GNUC__
                    941:           if (!found_segment) {
                    942:             ABORT("Can`t find correct Segments.\nSolution: Use an newer version of ixemul.library");
                    943:           }
                    944: #      endif
                    945:   }
                    946:
                    947: #if 0 /* old version */
                    948:   void GC_register_data_segments()
                    949:   {
                    950:     extern struct WBStartup *_WBenchMsg;
                    951:     struct Process     *proc;
                    952:     struct CommandLineInterface *cli;
                    953:     BPTR myseglist;
                    954:     ULONG *data;
                    955:
                    956:     if ( _WBenchMsg != 0 ) {
                    957:        if ((myseglist = _WBenchMsg->sm_Segment) == 0) {
                    958:            GC_err_puts("No seglist from workbench\n");
                    959:            return;
                    960:        }
                    961:     } else {
                    962:        if ((proc = (struct Process *)FindTask(0)) == 0) {
                    963:            GC_err_puts("Cannot find process structure\n");
                    964:            return;
                    965:        }
                    966:        if ((cli = BADDR(proc->pr_CLI)) == 0) {
                    967:            GC_err_puts("No CLI\n");
                    968:            return;
                    969:        }
                    970:        if ((myseglist = cli->cli_Module) == 0) {
                    971:            GC_err_puts("No seglist from CLI\n");
                    972:            return;
                    973:        }
                    974:     }
                    975:
                    976:     for (data = (ULONG *)BADDR(myseglist); data != 0;
                    977:          data = (ULONG *)BADDR(data[0])) {
                    978: #        ifdef AMIGA_SKIP_SEG
                    979:            if (((ULONG) GC_register_data_segments < (ULONG) &data[1]) ||
                    980:            ((ULONG) GC_register_data_segments > (ULONG) &data[1] + data[-1])) {
                    981: #       else
                    982:           {
                    983: #       endif /* AMIGA_SKIP_SEG */
                    984:           GC_add_roots_inner((char *)&data[1],
                    985:                             ((char *)&data[1]) + data[-1], FALSE);
                    986:          }
                    987:     }
                    988:   }
                    989: #endif /* old version */
                    990:
                    991:
                    992: # else
                    993:
                    994: # if (defined(SVR4) || defined(AUX) || defined(DGUX)) && !defined(PCR)
                    995: char * GC_SysVGetDataStart(max_page_size, etext_addr)
                    996: int max_page_size;
                    997: int * etext_addr;
                    998: {
                    999:     word text_end = ((word)(etext_addr) + sizeof(word) - 1)
                   1000:                    & ~(sizeof(word) - 1);
                   1001:        /* etext rounded to word boundary       */
                   1002:     word next_page = ((text_end + (word)max_page_size - 1)
                   1003:                      & ~((word)max_page_size - 1));
                   1004:     word page_offset = (text_end & ((word)max_page_size - 1));
                   1005:     VOLATILE char * result = (char *)(next_page + page_offset);
                   1006:     /* Note that this isnt equivalent to just adding           */
                   1007:     /* max_page_size to &etext if &etext is at a page boundary */
                   1008:
                   1009:     GC_setup_temporary_fault_handler();
                   1010:     if (setjmp(GC_jmp_buf) == 0) {
                   1011:        /* Try writing to the address.  */
                   1012:        *result = *result;
                   1013:         GC_reset_fault_handler();
                   1014:     } else {
                   1015:         GC_reset_fault_handler();
                   1016:        /* We got here via a longjmp.  The address is not readable.     */
                   1017:        /* This is known to happen under Solaris 2.4 + gcc, which place */
                   1018:        /* string constants in the text segment, but after etext.       */
                   1019:        /* Use plan B.  Note that we now know there is a gap between    */
                   1020:        /* text and data segments, so plan A bought us something.       */
                   1021:        result = (char *)GC_find_limit((ptr_t)(DATAEND) - MIN_PAGE_SIZE, FALSE);
                   1022:     }
                   1023:     return((char *)result);
                   1024: }
                   1025: # endif
                   1026:
                   1027:
                   1028: void GC_register_data_segments()
                   1029: {
                   1030: #   if !defined(PCR) && !defined(SRC_M3) && !defined(NEXT) && !defined(MACOS) \
                   1031:        && !defined(MACOSX)
                   1032: #     if defined(REDIRECT_MALLOC) && defined(SOLARIS_THREADS)
                   1033:        /* As of Solaris 2.3, the Solaris threads implementation        */
                   1034:        /* allocates the data structure for the initial thread with     */
                   1035:        /* sbrk at process startup.  It needs to be scanned, so that    */
                   1036:        /* we don't lose some malloc allocated data structures          */
                   1037:        /* hanging from it.  We're on thin ice here ...                 */
                   1038:         extern caddr_t sbrk();
                   1039:
                   1040:        GC_add_roots_inner(DATASTART, (char *)sbrk(0), FALSE);
                   1041: #     else
                   1042:        GC_add_roots_inner(DATASTART, (char *)(DATAEND), FALSE);
                   1043: #     endif
                   1044: #   endif
                   1045: #   if !defined(PCR) && (defined(NEXT) || defined(MACOSX))
                   1046:       GC_add_roots_inner(DATASTART, (char *) get_end(), FALSE);
                   1047: #   endif
                   1048: #   if defined(MACOS)
                   1049:     {
                   1050: #   if defined(THINK_C)
                   1051:        extern void* GC_MacGetDataStart(void);
                   1052:        /* globals begin above stack and end at a5. */
                   1053:        GC_add_roots_inner((ptr_t)GC_MacGetDataStart(),
                   1054:                           (ptr_t)LMGetCurrentA5(), FALSE);
                   1055: #   else
                   1056: #     if defined(__MWERKS__)
                   1057: #       if !__POWERPC__
                   1058:          extern void* GC_MacGetDataStart(void);
                   1059:          /* MATTHEW: Function to handle Far Globals (CW Pro 3) */
                   1060: #         if __option(far_data)
                   1061:          extern void* GC_MacGetDataEnd(void);
                   1062: #         endif
                   1063:          /* globals begin above stack and end at a5. */
                   1064:          GC_add_roots_inner((ptr_t)GC_MacGetDataStart(),
                   1065:                             (ptr_t)LMGetCurrentA5(), FALSE);
                   1066:          /* MATTHEW: Handle Far Globals */
                   1067: #         if __option(far_data)
                   1068:       /* Far globals follow he QD globals: */
                   1069:          GC_add_roots_inner((ptr_t)LMGetCurrentA5(),
                   1070:                             (ptr_t)GC_MacGetDataEnd(), FALSE);
                   1071: #         endif
                   1072: #       else
                   1073:          extern char __data_start__[], __data_end__[];
                   1074:          GC_add_roots_inner((ptr_t)&__data_start__,
                   1075:                             (ptr_t)&__data_end__, FALSE);
                   1076: #       endif /* __POWERPC__ */
                   1077: #     endif /* __MWERKS__ */
                   1078: #   endif /* !THINK_C */
                   1079:     }
                   1080: #   endif /* MACOS */
                   1081:
                   1082:     /* Dynamic libraries are added at every collection, since they may  */
                   1083:     /* change.                                                         */
                   1084: }
                   1085:
                   1086: # endif  /* ! AMIGA */
                   1087: # endif  /* ! MSWIN32 */
                   1088: # endif  /* ! OS2 */
                   1089:
                   1090: /*
                   1091:  * Auxiliary routines for obtaining memory from OS.
                   1092:  */
                   1093:
                   1094: # if !defined(OS2) && !defined(PCR) && !defined(AMIGA) \
                   1095:        && !defined(MSWIN32) && !defined(MACOS) && !defined(DOS4GW)
                   1096:
                   1097: # ifdef SUNOS4
                   1098:     extern caddr_t sbrk();
                   1099: # endif
                   1100: # ifdef __STDC__
                   1101: #   define SBRK_ARG_T ptrdiff_t
                   1102: # else
                   1103: #   define SBRK_ARG_T int
                   1104: # endif
                   1105:
                   1106: # ifdef RS6000
                   1107: /* The compiler seems to generate speculative reads one past the end of        */
                   1108: /* an allocated object.  Hence we need to make sure that the page      */
                   1109: /* following the last heap page is also mapped.                                */
                   1110: ptr_t GC_unix_get_mem(bytes)
                   1111: word bytes;
                   1112: {
                   1113:     caddr_t cur_brk = (caddr_t)sbrk(0);
                   1114:     caddr_t result;
                   1115:     SBRK_ARG_T lsbs = (word)cur_brk & (GC_page_size-1);
                   1116:     static caddr_t my_brk_val = 0;
                   1117:
                   1118:     if ((SBRK_ARG_T)bytes < 0) return(0); /* too big */
                   1119:     if (lsbs != 0) {
                   1120:         if((caddr_t)(sbrk(GC_page_size - lsbs)) == (caddr_t)(-1)) return(0);
                   1121:     }
                   1122:     if (cur_brk == my_brk_val) {
                   1123:        /* Use the extra block we allocated last time. */
                   1124:         result = (ptr_t)sbrk((SBRK_ARG_T)bytes);
                   1125:         if (result == (caddr_t)(-1)) return(0);
                   1126:         result -= GC_page_size;
                   1127:     } else {
                   1128:         result = (ptr_t)sbrk(GC_page_size + (SBRK_ARG_T)bytes);
                   1129:         if (result == (caddr_t)(-1)) return(0);
                   1130:     }
                   1131:     my_brk_val = result + bytes + GC_page_size;        /* Always page aligned */
                   1132:     return((ptr_t)result);
                   1133: }
                   1134:
                   1135: #else  /* Not RS6000 */
                   1136:
                   1137: #if defined(USE_MMAP)
                   1138: /* Tested only under IRIX5 and Solaris 2 */
                   1139:
                   1140: #ifdef USE_MMAP_FIXED
                   1141: #   define GC_MMAP_FLAGS MAP_FIXED | MAP_PRIVATE
                   1142:        /* Seems to yield better performance on Solaris 2, but can      */
                   1143:        /* be unreliable if something is already mapped at the address. */
                   1144: #else
                   1145: #   define GC_MMAP_FLAGS MAP_PRIVATE
                   1146: #endif
                   1147:
                   1148: ptr_t GC_unix_get_mem(bytes)
                   1149: word bytes;
                   1150: {
                   1151:     static GC_bool initialized = FALSE;
                   1152:     static int fd;
                   1153:     void *result;
                   1154:     static ptr_t last_addr = HEAP_START;
                   1155:
                   1156:     if (!initialized) {
                   1157:        fd = open("/dev/zero", O_RDONLY);
                   1158:        initialized = TRUE;
                   1159:     }
                   1160:     if (bytes & (GC_page_size -1)) ABORT("Bad GET_MEM arg");
                   1161:     result = mmap(last_addr, bytes, PROT_READ | PROT_WRITE | OPT_PROT_EXEC,
                   1162:                  GC_MMAP_FLAGS, fd, 0/* offset */);
                   1163:     if (result == MAP_FAILED) return(0);
                   1164:     last_addr = (ptr_t)result + bytes + GC_page_size - 1;
                   1165:     last_addr = (ptr_t)((word)last_addr & ~(GC_page_size - 1));
                   1166:     return((ptr_t)result);
                   1167: }
                   1168:
                   1169: #else /* Not RS6000, not USE_MMAP */
                   1170: ptr_t GC_unix_get_mem(bytes)
                   1171: word bytes;
                   1172: {
                   1173:   ptr_t result;
                   1174: # ifdef IRIX5
                   1175:     /* Bare sbrk isn't thread safe.  Play by malloc rules.     */
                   1176:     /* The equivalent may be needed on other systems as well.  */
                   1177:     __LOCK_MALLOC();
                   1178: # endif
                   1179:   {
                   1180:     ptr_t cur_brk = (ptr_t)sbrk(0);
                   1181:     SBRK_ARG_T lsbs = (word)cur_brk & (GC_page_size-1);
                   1182:
                   1183:     if ((SBRK_ARG_T)bytes < 0) return(0); /* too big */
                   1184:     if (lsbs != 0) {
                   1185:         if((ptr_t)sbrk(GC_page_size - lsbs) == (ptr_t)(-1)) return(0);
                   1186:     }
                   1187:     result = (ptr_t)sbrk((SBRK_ARG_T)bytes);
                   1188:     if (result == (ptr_t)(-1)) result = 0;
                   1189:   }
                   1190: # ifdef IRIX5
                   1191:     __UNLOCK_MALLOC();
                   1192: # endif
                   1193:   return(result);
                   1194: }
                   1195:
                   1196: #endif /* Not USE_MMAP */
                   1197: #endif /* Not RS6000 */
                   1198:
                   1199: # endif /* UN*X */
                   1200:
                   1201: # ifdef OS2
                   1202:
                   1203: void * os2_alloc(size_t bytes)
                   1204: {
                   1205:     void * result;
                   1206:
                   1207:     if (DosAllocMem(&result, bytes, PAG_EXECUTE | PAG_READ |
                   1208:                                    PAG_WRITE | PAG_COMMIT)
                   1209:                    != NO_ERROR) {
                   1210:        return(0);
                   1211:     }
                   1212:     if (result == 0) return(os2_alloc(bytes));
                   1213:     return(result);
                   1214: }
                   1215:
                   1216: # endif /* OS2 */
                   1217:
                   1218:
                   1219: # ifdef MSWIN32
                   1220: word GC_n_heap_bases = 0;
                   1221:
                   1222: ptr_t GC_win32_get_mem(bytes)
                   1223: word bytes;
                   1224: {
                   1225:     ptr_t result;
                   1226:
                   1227:     if (GC_win32s) {
                   1228:        /* VirtualAlloc doesn't like PAGE_EXECUTE_READWRITE.    */
                   1229:        /* There are also unconfirmed rumors of other           */
                   1230:        /* problems, so we dodge the issue.                     */
                   1231:         result = (ptr_t) GlobalAlloc(0, bytes + HBLKSIZE);
                   1232:         result = (ptr_t)(((word)result + HBLKSIZE) & ~(HBLKSIZE-1));
                   1233:     } else {
                   1234:         result = (ptr_t) VirtualAlloc(NULL, bytes,
                   1235:                                      MEM_COMMIT | MEM_RESERVE,
                   1236:                                      PAGE_EXECUTE_READWRITE);
                   1237:     }
                   1238:     if (HBLKDISPL(result) != 0) ABORT("Bad VirtualAlloc result");
                   1239:        /* If I read the documentation correctly, this can      */
                   1240:        /* only happen if HBLKSIZE > 64k or not a power of 2.   */
                   1241:     if (GC_n_heap_bases >= MAX_HEAP_SECTS) ABORT("Too many heap sections");
                   1242:     GC_heap_bases[GC_n_heap_bases++] = result;
                   1243:     return(result);
                   1244: }
                   1245:
                   1246: void GC_win32_free_heap ()
                   1247: {
                   1248:     if (GC_win32s) {
                   1249:        while (GC_n_heap_bases > 0) {
                   1250:            GlobalFree (GC_heap_bases[--GC_n_heap_bases]);
                   1251:            GC_heap_bases[GC_n_heap_bases] = 0;
                   1252:        }
                   1253:     }
                   1254: }
                   1255:
                   1256:
                   1257: # endif
                   1258:
                   1259: #ifdef USE_MUNMAP
                   1260:
                   1261: /* For now, this only works on some Unix-like systems.  If you         */
                   1262: /* have something else, don't define USE_MUNMAP.               */
                   1263: /* We assume ANSI C to support this feature.                   */
                   1264: #include <unistd.h>
                   1265: #include <sys/mman.h>
                   1266: #include <sys/stat.h>
                   1267: #include <sys/types.h>
                   1268: #include <fcntl.h>
                   1269:
                   1270: /* Compute a page aligned starting address for the unmap       */
                   1271: /* operation on a block of size bytes starting at start.       */
                   1272: /* Return 0 if the block is too small to make this feasible.   */
                   1273: ptr_t GC_unmap_start(ptr_t start, word bytes)
                   1274: {
                   1275:     ptr_t result = start;
                   1276:     /* Round start to next page boundary.       */
                   1277:         result += GC_page_size - 1;
                   1278:         result = (ptr_t)((word)result & ~(GC_page_size - 1));
                   1279:     if (result + GC_page_size > start + bytes) return 0;
                   1280:     return result;
                   1281: }
                   1282:
                   1283: /* Compute end address for an unmap operation on the indicated */
                   1284: /* block.                                                      */
                   1285: ptr_t GC_unmap_end(ptr_t start, word bytes)
                   1286: {
                   1287:     ptr_t end_addr = start + bytes;
                   1288:     end_addr = (ptr_t)((word)end_addr & ~(GC_page_size - 1));
                   1289:     return end_addr;
                   1290: }
                   1291:
                   1292: /* We assume that GC_remap is called on exactly the same range */
                   1293: /* as a previous call to GC_unmap.  It is safe to consistently */
                   1294: /* round the endpoints in both places.                         */
                   1295: void GC_unmap(ptr_t start, word bytes)
                   1296: {
                   1297:     ptr_t start_addr = GC_unmap_start(start, bytes);
                   1298:     ptr_t end_addr = GC_unmap_end(start, bytes);
                   1299:     word len = end_addr - start_addr;
                   1300:     if (0 == start_addr) return;
                   1301:     if (munmap(start_addr, len) != 0) ABORT("munmap failed");
                   1302:     GC_unmapped_bytes += len;
                   1303: }
                   1304:
                   1305:
                   1306: void GC_remap(ptr_t start, word bytes)
                   1307: {
                   1308:     static int zero_descr = -1;
                   1309:     ptr_t start_addr = GC_unmap_start(start, bytes);
                   1310:     ptr_t end_addr = GC_unmap_end(start, bytes);
                   1311:     word len = end_addr - start_addr;
                   1312:     ptr_t result;
                   1313:
                   1314:     if (-1 == zero_descr) zero_descr = open("/dev/zero", O_RDWR);
                   1315:     if (0 == start_addr) return;
                   1316:     result = mmap(start_addr, len, PROT_READ | PROT_WRITE | OPT_PROT_EXEC,
                   1317:                  MAP_FIXED | MAP_PRIVATE, zero_descr, 0);
                   1318:     if (result != start_addr) {
                   1319:        ABORT("mmap remapping failed");
                   1320:     }
                   1321:     GC_unmapped_bytes -= len;
                   1322: }
                   1323:
                   1324: /* Two adjacent blocks have already been unmapped and are about to     */
                   1325: /* be merged.  Unmap the whole block.  This typically requires         */
                   1326: /* that we unmap a small section in the middle that was not previously */
                   1327: /* unmapped due to alignment constraints.                              */
                   1328: void GC_unmap_gap(ptr_t start1, word bytes1, ptr_t start2, word bytes2)
                   1329: {
                   1330:     ptr_t start1_addr = GC_unmap_start(start1, bytes1);
                   1331:     ptr_t end1_addr = GC_unmap_end(start1, bytes1);
                   1332:     ptr_t start2_addr = GC_unmap_start(start2, bytes2);
                   1333:     ptr_t end2_addr = GC_unmap_end(start2, bytes2);
                   1334:     ptr_t start_addr = end1_addr;
                   1335:     ptr_t end_addr = start2_addr;
                   1336:     word len;
                   1337:     GC_ASSERT(start1 + bytes1 == start2);
                   1338:     if (0 == start1_addr) start_addr = GC_unmap_start(start1, bytes1 + bytes2);
                   1339:     if (0 == start2_addr) end_addr = GC_unmap_end(start1, bytes1 + bytes2);
                   1340:     if (0 == start_addr) return;
                   1341:     len = end_addr - start_addr;
                   1342:     if (len != 0 && munmap(start_addr, len) != 0) ABORT("munmap failed");
                   1343:     GC_unmapped_bytes += len;
                   1344: }
                   1345:
                   1346: #endif /* USE_MUNMAP */
                   1347:
                   1348: /* Routine for pushing any additional roots.  In THREADS       */
                   1349: /* environment, this is also responsible for marking from      */
                   1350: /* thread stacks.  In the SRC_M3 case, it also handles         */
                   1351: /* global variables.                                           */
                   1352: #ifndef THREADS
                   1353: void (*GC_push_other_roots)() = 0;
                   1354: #else /* THREADS */
                   1355:
                   1356: # ifdef PCR
                   1357: PCR_ERes GC_push_thread_stack(PCR_Th_T *t, PCR_Any dummy)
                   1358: {
                   1359:     struct PCR_ThCtl_TInfoRep info;
                   1360:     PCR_ERes result;
                   1361:
                   1362:     info.ti_stkLow = info.ti_stkHi = 0;
                   1363:     result = PCR_ThCtl_GetInfo(t, &info);
                   1364:     GC_push_all_stack((ptr_t)(info.ti_stkLow), (ptr_t)(info.ti_stkHi));
                   1365:     return(result);
                   1366: }
                   1367:
                   1368: /* Push the contents of an old object. We treat this as stack  */
                   1369: /* data only becasue that makes it robust against mark stack   */
                   1370: /* overflow.                                                   */
                   1371: PCR_ERes GC_push_old_obj(void *p, size_t size, PCR_Any data)
                   1372: {
                   1373:     GC_push_all_stack((ptr_t)p, (ptr_t)p + size);
                   1374:     return(PCR_ERes_okay);
                   1375: }
                   1376:
                   1377:
                   1378: void GC_default_push_other_roots()
                   1379: {
                   1380:     /* Traverse data allocated by previous memory managers.            */
                   1381:        {
                   1382:          extern struct PCR_MM_ProcsRep * GC_old_allocator;
                   1383:
                   1384:          if ((*(GC_old_allocator->mmp_enumerate))(PCR_Bool_false,
                   1385:                                                   GC_push_old_obj, 0)
                   1386:              != PCR_ERes_okay) {
                   1387:              ABORT("Old object enumeration failed");
                   1388:          }
                   1389:        }
                   1390:     /* Traverse all thread stacks. */
                   1391:        if (PCR_ERes_IsErr(
                   1392:                 PCR_ThCtl_ApplyToAllOtherThreads(GC_push_thread_stack,0))
                   1393:               || PCR_ERes_IsErr(GC_push_thread_stack(PCR_Th_CurrThread(), 0))) {
                   1394:               ABORT("Thread stack marking failed\n");
                   1395:        }
                   1396: }
                   1397:
                   1398: # endif /* PCR */
                   1399:
                   1400: # ifdef SRC_M3
                   1401:
                   1402: # ifdef ALL_INTERIOR_POINTERS
                   1403:     --> misconfigured
                   1404: # endif
                   1405:
                   1406:
                   1407: extern void ThreadF__ProcessStacks();
                   1408:
                   1409: void GC_push_thread_stack(start, stop)
                   1410: word start, stop;
                   1411: {
                   1412:    GC_push_all_stack((ptr_t)start, (ptr_t)stop + sizeof(word));
                   1413: }
                   1414:
                   1415: /* Push routine with M3 specific calling convention. */
                   1416: GC_m3_push_root(dummy1, p, dummy2, dummy3)
                   1417: word *p;
                   1418: ptr_t dummy1, dummy2;
                   1419: int dummy3;
                   1420: {
                   1421:     word q = *p;
                   1422:
                   1423:     if ((ptr_t)(q) >= GC_least_plausible_heap_addr
                   1424:         && (ptr_t)(q) < GC_greatest_plausible_heap_addr) {
                   1425:         GC_push_one_checked(q,FALSE);
                   1426:     }
                   1427: }
                   1428:
                   1429: /* M3 set equivalent to RTHeap.TracedRefTypes */
                   1430: typedef struct { int elts[1]; }  RefTypeSet;
                   1431: RefTypeSet GC_TracedRefTypes = {{0x1}};
                   1432:
                   1433: /* From finalize.c */
                   1434: extern void GC_push_finalizer_structures();
                   1435:
                   1436: /* From stubborn.c: */
                   1437: # ifdef STUBBORN_ALLOC
                   1438:     extern GC_PTR * GC_changing_list_start;
                   1439: # endif
                   1440:
                   1441:
                   1442: void GC_default_push_other_roots()
                   1443: {
                   1444:     /* Use the M3 provided routine for finding static roots.   */
                   1445:     /* This is a bit dubious, since it presumes no C roots.    */
                   1446:     /* We handle the collector roots explicitly.               */
                   1447:        {
                   1448: #       ifdef STUBBORN_ALLOC
                   1449:            GC_push_one(GC_changing_list_start);
                   1450: #       endif
                   1451:         GC_push_finalizer_structures();
                   1452:         RTMain__GlobalMapProc(GC_m3_push_root, 0, GC_TracedRefTypes);
                   1453:        }
                   1454:        if (GC_words_allocd > 0) {
                   1455:            ThreadF__ProcessStacks(GC_push_thread_stack);
                   1456:        }
                   1457:        /* Otherwise this isn't absolutely necessary, and we have       */
                   1458:        /* startup ordering problems.                                   */
                   1459: }
                   1460:
                   1461: # endif /* SRC_M3 */
                   1462:
                   1463: # if defined(SOLARIS_THREADS) || defined(WIN32_THREADS) \
                   1464:      || defined(IRIX_THREADS) || defined(LINUX_THREADS) \
                   1465:      || defined(IRIX_PCR_THREADS)
                   1466:
                   1467: extern void GC_push_all_stacks();
                   1468:
                   1469: void GC_default_push_other_roots()
                   1470: {
                   1471:     GC_push_all_stacks();
                   1472: }
                   1473:
                   1474: # endif /* SOLARIS_THREADS || ... */
                   1475:
                   1476: void (*GC_push_other_roots)() = GC_default_push_other_roots;
                   1477:
                   1478: #endif
                   1479:
                   1480: /*
                   1481:  * Routines for accessing dirty  bits on virtual pages.
                   1482:  * We plan to eventaually implement four strategies for doing so:
                   1483:  * DEFAULT_VDB:        A simple dummy implementation that treats every page
                   1484:  *             as possibly dirty.  This makes incremental collection
                   1485:  *             useless, but the implementation is still correct.
                   1486:  * PCR_VDB:    Use PPCRs virtual dirty bit facility.
                   1487:  * PROC_VDB:   Use the /proc facility for reading dirty bits.  Only
                   1488:  *             works under some SVR4 variants.  Even then, it may be
                   1489:  *             too slow to be entirely satisfactory.  Requires reading
                   1490:  *             dirty bits for entire address space.  Implementations tend
                   1491:  *             to assume that the client is a (slow) debugger.
                   1492:  * MPROTECT_VDB:Protect pages and then catch the faults to keep track of
                   1493:  *             dirtied pages.  The implementation (and implementability)
                   1494:  *             is highly system dependent.  This usually fails when system
                   1495:  *             calls write to a protected page.  We prevent the read system
                   1496:  *             call from doing so.  It is the clients responsibility to
                   1497:  *             make sure that other system calls are similarly protected
                   1498:  *             or write only to the stack.
                   1499:  */
                   1500:
                   1501: GC_bool GC_dirty_maintained = FALSE;
                   1502:
                   1503: # ifdef DEFAULT_VDB
                   1504:
                   1505: /* All of the following assume the allocation lock is held, and        */
                   1506: /* signals are disabled.                                       */
                   1507:
                   1508: /* The client asserts that unallocated pages in the heap are never     */
                   1509: /* written.                                                            */
                   1510:
                   1511: /* Initialize virtual dirty bit implementation.                        */
                   1512: void GC_dirty_init()
                   1513: {
                   1514:     GC_dirty_maintained = TRUE;
                   1515: }
                   1516:
                   1517: /* Retrieve system dirty bits for heap to a local buffer.      */
                   1518: /* Restore the systems notion of which pages are dirty.                */
                   1519: void GC_read_dirty()
                   1520: {}
                   1521:
                   1522: /* Is the HBLKSIZE sized page at h marked dirty in the local buffer?   */
                   1523: /* If the actual page size is different, this returns TRUE if any      */
                   1524: /* of the pages overlapping h are dirty.  This routine may err on the  */
                   1525: /* side of labelling pages as dirty (and this implementation does).    */
                   1526: /*ARGSUSED*/
                   1527: GC_bool GC_page_was_dirty(h)
                   1528: struct hblk *h;
                   1529: {
                   1530:     return(TRUE);
                   1531: }
                   1532:
                   1533: /*
                   1534:  * The following two routines are typically less crucial.  They matter
                   1535:  * most with large dynamic libraries, or if we can't accurately identify
                   1536:  * stacks, e.g. under Solaris 2.X.  Otherwise the following default
                   1537:  * versions are adequate.
                   1538:  */
                   1539:
                   1540: /* Could any valid GC heap pointer ever have been written to this page?        */
                   1541: /*ARGSUSED*/
                   1542: GC_bool GC_page_was_ever_dirty(h)
                   1543: struct hblk *h;
                   1544: {
                   1545:     return(TRUE);
                   1546: }
                   1547:
                   1548: /* Reset the n pages starting at h to "was never dirty" status.        */
                   1549: void GC_is_fresh(h, n)
                   1550: struct hblk *h;
                   1551: word n;
                   1552: {
                   1553: }
                   1554:
                   1555: /* A call hints that h is about to be written. */
                   1556: /* May speed up some dirty bit implementations.        */
                   1557: /*ARGSUSED*/
                   1558: void GC_write_hint(h)
                   1559: struct hblk *h;
                   1560: {
                   1561: }
                   1562:
                   1563: # endif /* DEFAULT_VDB */
                   1564:
                   1565:
                   1566: # ifdef MPROTECT_VDB
                   1567:
                   1568: /*
                   1569:  * See DEFAULT_VDB for interface descriptions.
                   1570:  */
                   1571:
                   1572: /*
                   1573:  * This implementation maintains dirty bits itself by catching write
                   1574:  * faults and keeping track of them.  We assume nobody else catches
                   1575:  * SIGBUS or SIGSEGV.  We assume no write faults occur in system calls
                   1576:  * except as a result of a read system call.  This means clients must
                   1577:  * either ensure that system calls do not touch the heap, or must
                   1578:  * provide their own wrappers analogous to the one for read.
                   1579:  * We assume the page size is a multiple of HBLKSIZE.
                   1580:  * This implementation is currently SunOS 4.X and IRIX 5.X specific, though we
                   1581:  * tried to use portable code where easily possible.  It is known
                   1582:  * not to work under a number of other systems.
                   1583:  */
                   1584:
                   1585: # ifndef MSWIN32
                   1586:
                   1587: #   include <sys/mman.h>
                   1588: #   include <signal.h>
                   1589: #   include <sys/syscall.h>
                   1590:
                   1591: #   define PROTECT(addr, len) \
                   1592:          if (mprotect((caddr_t)(addr), (int)(len), \
                   1593:                       PROT_READ | OPT_PROT_EXEC) < 0) { \
                   1594:            ABORT("mprotect failed"); \
                   1595:          }
                   1596: #   define UNPROTECT(addr, len) \
                   1597:          if (mprotect((caddr_t)(addr), (int)(len), \
                   1598:                       PROT_WRITE | PROT_READ | OPT_PROT_EXEC ) < 0) { \
                   1599:            ABORT("un-mprotect failed"); \
                   1600:          }
                   1601:
                   1602: # else
                   1603:
                   1604: #   include <signal.h>
                   1605:
                   1606:     static DWORD protect_junk;
                   1607: #   define PROTECT(addr, len) \
                   1608:          if (!VirtualProtect((addr), (len), PAGE_EXECUTE_READ, \
                   1609:                              &protect_junk)) { \
                   1610:            DWORD last_error = GetLastError(); \
                   1611:            GC_printf1("Last error code: %lx\n", last_error); \
                   1612:            ABORT("VirtualProtect failed"); \
                   1613:          }
                   1614: #   define UNPROTECT(addr, len) \
                   1615:          if (!VirtualProtect((addr), (len), PAGE_EXECUTE_READWRITE, \
                   1616:                              &protect_junk)) { \
                   1617:            ABORT("un-VirtualProtect failed"); \
                   1618:          }
                   1619:
                   1620: # endif
                   1621:
                   1622: #if defined(SUNOS4) || defined(FREEBSD)
                   1623:     typedef void (* SIG_PF)();
                   1624: #endif
                   1625: #if defined(SUNOS5SIGS) || defined(OSF1) || defined(LINUX)
                   1626:     typedef void (* SIG_PF)(int);
                   1627: #endif
                   1628: #if defined(MSWIN32)
                   1629:     typedef LPTOP_LEVEL_EXCEPTION_FILTER SIG_PF;
                   1630: #   undef SIG_DFL
                   1631: #   define SIG_DFL (LPTOP_LEVEL_EXCEPTION_FILTER) (-1)
                   1632: #endif
                   1633:
                   1634: #if defined(IRIX5) || defined(OSF1)
                   1635:     typedef void (* REAL_SIG_PF)(int, int, struct sigcontext *);
                   1636: #endif
                   1637: #if defined(SUNOS5SIGS)
                   1638:     typedef void (* REAL_SIG_PF)(int, struct siginfo *, void *);
                   1639: #endif
                   1640: #if defined(LINUX)
                   1641: #   include <linux/version.h>
                   1642: #   if (LINUX_VERSION_CODE >= 0x20100) && !defined(M68K) || defined(ALPHA)
                   1643:       typedef struct sigcontext s_c;
                   1644: #   else
                   1645:       typedef struct sigcontext_struct s_c;
                   1646: #   endif
                   1647: #   ifdef ALPHA
                   1648:     typedef void (* REAL_SIG_PF)(int, int, s_c *);
                   1649:     /* Retrieve fault address from sigcontext structure by decoding    */
                   1650:     /* instruction.                                                    */
                   1651:     char * get_fault_addr(s_c *sc) {
                   1652:         unsigned instr;
                   1653:        word faultaddr;
                   1654:
                   1655:        instr = *((unsigned *)(sc->sc_pc));
                   1656:        faultaddr = sc->sc_regs[(instr >> 16) & 0x1f];
                   1657:        faultaddr += (word) (((int)instr << 16) >> 16);
                   1658:        return (char *)faultaddr;
                   1659:     }
                   1660: #   else /* !ALPHA */
                   1661:     typedef void (* REAL_SIG_PF)(int, s_c);
                   1662: #   endif /* !ALPHA */
                   1663: # endif
                   1664:
                   1665: SIG_PF GC_old_bus_handler;
                   1666: SIG_PF GC_old_segv_handler;    /* Also old MSWIN32 ACCESS_VIOLATION filter */
                   1667:
                   1668: /*ARGSUSED*/
                   1669: # if defined (SUNOS4) || defined(FREEBSD)
                   1670:     void GC_write_fault_handler(sig, code, scp, addr)
                   1671:     int sig, code;
                   1672:     struct sigcontext *scp;
                   1673:     char * addr;
                   1674: #   ifdef SUNOS4
                   1675: #     define SIG_OK (sig == SIGSEGV || sig == SIGBUS)
                   1676: #     define CODE_OK (FC_CODE(code) == FC_PROT \
                   1677:                    || (FC_CODE(code) == FC_OBJERR \
                   1678:                       && FC_ERRNO(code) == FC_PROT))
                   1679: #   endif
                   1680: #   ifdef FREEBSD
                   1681: #     define SIG_OK (sig == SIGBUS)
                   1682: #     define CODE_OK (code == BUS_PAGE_FAULT)
                   1683: #   endif
                   1684: # endif
                   1685: # if defined(IRIX5) || defined(OSF1)
                   1686: #   include <errno.h>
                   1687:     void GC_write_fault_handler(int sig, int code, struct sigcontext *scp)
                   1688: #   define SIG_OK (sig == SIGSEGV)
                   1689: #   ifdef OSF1
                   1690: #     define CODE_OK (code == 2 /* experimentally determined */)
                   1691: #   endif
                   1692: #   ifdef IRIX5
                   1693: #     define CODE_OK (code == EACCES)
                   1694: #   endif
                   1695: # endif
                   1696: # if defined(LINUX)
                   1697: #   ifdef ALPHA
                   1698:       void GC_write_fault_handler(int sig, int code, s_c * sc)
                   1699: #   else
                   1700:       void GC_write_fault_handler(int sig, s_c sc)
                   1701: #   endif
                   1702: #   define SIG_OK (sig == SIGSEGV)
                   1703: #   define CODE_OK TRUE
                   1704:        /* Empirically c.trapno == 14, but is that useful?      */
                   1705:        /* We assume Intel architecture, so alignment           */
                   1706:        /* faults are not possible.                             */
                   1707: # endif
                   1708: # if defined(SUNOS5SIGS)
                   1709:     void GC_write_fault_handler(int sig, struct siginfo *scp, void * context)
                   1710: #   define SIG_OK (sig == SIGSEGV)
                   1711: #   define CODE_OK (scp -> si_code == SEGV_ACCERR)
                   1712: # endif
                   1713: # if defined(MSWIN32)
                   1714:     LONG WINAPI GC_write_fault_handler(struct _EXCEPTION_POINTERS *exc_info)
                   1715: #   define SIG_OK (exc_info -> ExceptionRecord -> ExceptionCode == \
                   1716:                        EXCEPTION_ACCESS_VIOLATION)
                   1717: #   define CODE_OK (exc_info -> ExceptionRecord -> ExceptionInformation[0] == 1)
                   1718:                        /* Write fault */
                   1719: # endif
                   1720: {
                   1721:     register unsigned i;
                   1722: #   ifdef IRIX5
                   1723:        char * addr = (char *) (size_t) (scp -> sc_badvaddr);
                   1724: #   endif
                   1725: #   if defined(OSF1) && defined(ALPHA)
                   1726:        char * addr = (char *) (scp -> sc_traparg_a0);
                   1727: #   endif
                   1728: #   ifdef SUNOS5SIGS
                   1729:        char * addr = (char *) (scp -> si_addr);
                   1730: #   endif
                   1731: #   ifdef LINUX
                   1732: #     ifdef I386
                   1733:        char * addr = (char *) (sc.cr2);
                   1734: #     else
                   1735: #      if defined(M68K)
                   1736:           char * addr = NULL;
                   1737:
                   1738:          struct sigcontext *scp = (struct sigcontext *)(&sc);
                   1739:
                   1740:          int format = (scp->sc_formatvec >> 12) & 0xf;
                   1741:          unsigned long *framedata = (unsigned long *)(scp + 1);
                   1742:          unsigned long ea;
                   1743:
                   1744:          if (format == 0xa || format == 0xb) {
                   1745:                /* 68020/030 */
                   1746:                ea = framedata[2];
                   1747:          } else if (format == 7) {
                   1748:                /* 68040 */
                   1749:                ea = framedata[3];
                   1750:          } else if (format == 4) {
                   1751:                /* 68060 */
                   1752:                ea = framedata[0];
                   1753:                if (framedata[1] & 0x08000000) {
                   1754:                        /* correct addr on misaligned access */
                   1755:                        ea = (ea+4095)&(~4095);
                   1756:                }
                   1757:          }
                   1758:          addr = (char *)ea;
                   1759: #      else
                   1760: #        ifdef ALPHA
                   1761:             char * addr = get_fault_addr(sc);
                   1762: #        else
                   1763:                --> architecture not supported
                   1764: #        endif
                   1765: #      endif
                   1766: #     endif
                   1767: #   endif
                   1768: #   if defined(MSWIN32)
                   1769:        char * addr = (char *) (exc_info -> ExceptionRecord
                   1770:                                -> ExceptionInformation[1]);
                   1771: #      define sig SIGSEGV
                   1772: #   endif
                   1773:
                   1774:     if (SIG_OK && CODE_OK) {
                   1775:         register struct hblk * h =
                   1776:                        (struct hblk *)((word)addr & ~(GC_page_size-1));
                   1777:         GC_bool in_allocd_block;
                   1778:
                   1779: #      ifdef SUNOS5SIGS
                   1780:            /* Address is only within the correct physical page.        */
                   1781:            in_allocd_block = FALSE;
                   1782:             for (i = 0; i < divHBLKSZ(GC_page_size); i++) {
                   1783:               if (HDR(h+i) != 0) {
                   1784:                 in_allocd_block = TRUE;
                   1785:               }
                   1786:             }
                   1787: #      else
                   1788:            in_allocd_block = (HDR(addr) != 0);
                   1789: #      endif
                   1790:         if (!in_allocd_block) {
                   1791:            /* Heap blocks now begin and end on page boundaries */
                   1792:             SIG_PF old_handler;
                   1793:
                   1794:             if (sig == SIGSEGV) {
                   1795:                old_handler = GC_old_segv_handler;
                   1796:             } else {
                   1797:                 old_handler = GC_old_bus_handler;
                   1798:             }
                   1799:             if (old_handler == SIG_DFL) {
                   1800: #              ifndef MSWIN32
                   1801:                    GC_err_printf1("Segfault at 0x%lx\n", addr);
                   1802:                     ABORT("Unexpected bus error or segmentation fault");
                   1803: #              else
                   1804:                    return(EXCEPTION_CONTINUE_SEARCH);
                   1805: #              endif
                   1806:             } else {
                   1807: #              if defined (SUNOS4) || defined(FREEBSD)
                   1808:                    (*old_handler) (sig, code, scp, addr);
                   1809:                    return;
                   1810: #              endif
                   1811: #              if defined (SUNOS5SIGS)
                   1812:                    (*(REAL_SIG_PF)old_handler) (sig, scp, context);
                   1813:                    return;
                   1814: #              endif
                   1815: #              if defined (LINUX)
                   1816: #                  ifdef ALPHA
                   1817:                        (*(REAL_SIG_PF)old_handler) (sig, code, sc);
                   1818: #                  else
                   1819:                        (*(REAL_SIG_PF)old_handler) (sig, sc);
                   1820: #                  endif
                   1821:                    return;
                   1822: #              endif
                   1823: #              if defined (IRIX5) || defined(OSF1)
                   1824:                    (*(REAL_SIG_PF)old_handler) (sig, code, scp);
                   1825:                    return;
                   1826: #              endif
                   1827: #              ifdef MSWIN32
                   1828:                    return((*old_handler)(exc_info));
                   1829: #              endif
                   1830:             }
                   1831:         }
                   1832:         for (i = 0; i < divHBLKSZ(GC_page_size); i++) {
                   1833:             register int index = PHT_HASH(h+i);
                   1834:
                   1835:             set_pht_entry_from_index(GC_dirty_pages, index);
                   1836:         }
                   1837:         UNPROTECT(h, GC_page_size);
                   1838: #      if defined(OSF1) || defined(LINUX)
                   1839:            /* These reset the signal handler each time by default. */
                   1840:            signal(SIGSEGV, (SIG_PF) GC_write_fault_handler);
                   1841: #      endif
                   1842:        /* The write may not take place before dirty bits are read.     */
                   1843:        /* But then we'll fault again ...                               */
                   1844: #      ifdef MSWIN32
                   1845:            return(EXCEPTION_CONTINUE_EXECUTION);
                   1846: #      else
                   1847:            return;
                   1848: #      endif
                   1849:     }
                   1850: #ifdef MSWIN32
                   1851:     return EXCEPTION_CONTINUE_SEARCH;
                   1852: #else
                   1853:     GC_err_printf1("Segfault at 0x%lx\n", addr);
                   1854:     ABORT("Unexpected bus error or segmentation fault");
                   1855: #endif
                   1856: }
                   1857:
                   1858: /*
                   1859:  * We hold the allocation lock.  We expect block h to be written
                   1860:  * shortly.
                   1861:  */
                   1862: void GC_write_hint(h)
                   1863: struct hblk *h;
                   1864: {
                   1865:     register struct hblk * h_trunc;
                   1866:     register unsigned i;
                   1867:     register GC_bool found_clean;
                   1868:
                   1869:     if (!GC_dirty_maintained) return;
                   1870:     h_trunc = (struct hblk *)((word)h & ~(GC_page_size-1));
                   1871:     found_clean = FALSE;
                   1872:     for (i = 0; i < divHBLKSZ(GC_page_size); i++) {
                   1873:         register int index = PHT_HASH(h_trunc+i);
                   1874:
                   1875:         if (!get_pht_entry_from_index(GC_dirty_pages, index)) {
                   1876:             found_clean = TRUE;
                   1877:             set_pht_entry_from_index(GC_dirty_pages, index);
                   1878:         }
                   1879:     }
                   1880:     if (found_clean) {
                   1881:        UNPROTECT(h_trunc, GC_page_size);
                   1882:     }
                   1883: }
                   1884:
                   1885: void GC_dirty_init()
                   1886: {
                   1887: #if defined(SUNOS5SIGS) || defined(IRIX5) /* || defined(OSF1) */
                   1888:     struct sigaction   act, oldact;
                   1889: #   ifdef IRIX5
                   1890:        act.sa_flags    = SA_RESTART;
                   1891:         act.sa_handler  = GC_write_fault_handler;
                   1892: #   else
                   1893:        act.sa_flags    = SA_RESTART | SA_SIGINFO;
                   1894:         act.sa_sigaction = GC_write_fault_handler;
                   1895: #   endif
                   1896:     (void)sigemptyset(&act.sa_mask);
                   1897: #endif
                   1898: #   ifdef PRINTSTATS
                   1899:        GC_printf0("Inititalizing mprotect virtual dirty bit implementation\n");
                   1900: #   endif
                   1901:     GC_dirty_maintained = TRUE;
                   1902:     if (GC_page_size % HBLKSIZE != 0) {
                   1903:         GC_err_printf0("Page size not multiple of HBLKSIZE\n");
                   1904:         ABORT("Page size not multiple of HBLKSIZE");
                   1905:     }
                   1906: #   if defined(SUNOS4) || defined(FREEBSD)
                   1907:       GC_old_bus_handler = signal(SIGBUS, GC_write_fault_handler);
                   1908:       if (GC_old_bus_handler == SIG_IGN) {
                   1909:         GC_err_printf0("Previously ignored bus error!?");
                   1910:         GC_old_bus_handler = SIG_DFL;
                   1911:       }
                   1912:       if (GC_old_bus_handler != SIG_DFL) {
                   1913: #      ifdef PRINTSTATS
                   1914:           GC_err_printf0("Replaced other SIGBUS handler\n");
                   1915: #      endif
                   1916:       }
                   1917: #   endif
                   1918: #   if defined(OSF1) || defined(SUNOS4) || defined(LINUX)
                   1919:       GC_old_segv_handler = signal(SIGSEGV, (SIG_PF)GC_write_fault_handler);
                   1920:       if (GC_old_segv_handler == SIG_IGN) {
                   1921:         GC_err_printf0("Previously ignored segmentation violation!?");
                   1922:         GC_old_segv_handler = SIG_DFL;
                   1923:       }
                   1924:       if (GC_old_segv_handler != SIG_DFL) {
                   1925: #      ifdef PRINTSTATS
                   1926:           GC_err_printf0("Replaced other SIGSEGV handler\n");
                   1927: #      endif
                   1928:       }
                   1929: #   endif
                   1930: #   if defined(SUNOS5SIGS) || defined(IRIX5)
                   1931: #     if defined(IRIX_THREADS) || defined(IRIX_PCR_THREADS)
                   1932:        sigaction(SIGSEGV, 0, &oldact);
                   1933:        sigaction(SIGSEGV, &act, 0);
                   1934: #     else
                   1935:        sigaction(SIGSEGV, &act, &oldact);
                   1936: #     endif
                   1937: #     if defined(_sigargs)
                   1938:        /* This is Irix 5.x, not 6.x.  Irix 5.x does not have   */
                   1939:        /* sa_sigaction.                                        */
                   1940:        GC_old_segv_handler = oldact.sa_handler;
                   1941: #     else /* Irix 6.x or SUNOS5SIGS */
                   1942:         if (oldact.sa_flags & SA_SIGINFO) {
                   1943:           GC_old_segv_handler = (SIG_PF)(oldact.sa_sigaction);
                   1944:         } else {
                   1945:           GC_old_segv_handler = oldact.sa_handler;
                   1946:         }
                   1947: #     endif
                   1948:       if (GC_old_segv_handler == SIG_IGN) {
                   1949:             GC_err_printf0("Previously ignored segmentation violation!?");
                   1950:             GC_old_segv_handler = SIG_DFL;
                   1951:       }
                   1952:       if (GC_old_segv_handler != SIG_DFL) {
                   1953: #       ifdef PRINTSTATS
                   1954:          GC_err_printf0("Replaced other SIGSEGV handler\n");
                   1955: #       endif
                   1956:       }
                   1957: #    endif
                   1958: #   if defined(MSWIN32)
                   1959:       GC_old_segv_handler = SetUnhandledExceptionFilter(GC_write_fault_handler);
                   1960:       if (GC_old_segv_handler != NULL) {
                   1961: #      ifdef PRINTSTATS
                   1962:           GC_err_printf0("Replaced other UnhandledExceptionFilter\n");
                   1963: #      endif
                   1964:       } else {
                   1965:           GC_old_segv_handler = SIG_DFL;
                   1966:       }
                   1967: #   endif
                   1968: }
                   1969:
                   1970:
                   1971:
                   1972: void GC_protect_heap()
                   1973: {
                   1974:     ptr_t start;
                   1975:     word len;
                   1976:     unsigned i;
                   1977:
                   1978:     for (i = 0; i < GC_n_heap_sects; i++) {
                   1979:         start = GC_heap_sects[i].hs_start;
                   1980:         len = GC_heap_sects[i].hs_bytes;
                   1981:         PROTECT(start, len);
                   1982:     }
                   1983: }
                   1984:
                   1985: /* We assume that either the world is stopped or its OK to lose dirty  */
                   1986: /* bits while this is happenning (as in GC_enable_incremental).                */
                   1987: void GC_read_dirty()
                   1988: {
                   1989:     BCOPY((word *)GC_dirty_pages, GC_grungy_pages,
                   1990:           (sizeof GC_dirty_pages));
                   1991:     BZERO((word *)GC_dirty_pages, (sizeof GC_dirty_pages));
                   1992:     GC_protect_heap();
                   1993: }
                   1994:
                   1995: GC_bool GC_page_was_dirty(h)
                   1996: struct hblk * h;
                   1997: {
                   1998:     register word index = PHT_HASH(h);
                   1999:
                   2000:     return(HDR(h) == 0 || get_pht_entry_from_index(GC_grungy_pages, index));
                   2001: }
                   2002:
                   2003: /*
                   2004:  * Acquiring the allocation lock here is dangerous, since this
                   2005:  * can be called from within GC_call_with_alloc_lock, and the cord
                   2006:  * package does so.  On systems that allow nested lock acquisition, this
                   2007:  * happens to work.
                   2008:  * On other systems, SET_LOCK_HOLDER and friends must be suitably defined.
                   2009:  */
                   2010:
                   2011: void GC_begin_syscall()
                   2012: {
                   2013:     if (!I_HOLD_LOCK()) LOCK();
                   2014: }
                   2015:
                   2016: void GC_end_syscall()
                   2017: {
                   2018:     if (!I_HOLD_LOCK()) UNLOCK();
                   2019: }
                   2020:
                   2021: void GC_unprotect_range(addr, len)
                   2022: ptr_t addr;
                   2023: word len;
                   2024: {
                   2025:     struct hblk * start_block;
                   2026:     struct hblk * end_block;
                   2027:     register struct hblk *h;
                   2028:     ptr_t obj_start;
                   2029:
                   2030:     if (!GC_incremental) return;
                   2031:     obj_start = GC_base(addr);
                   2032:     if (obj_start == 0) return;
                   2033:     if (GC_base(addr + len - 1) != obj_start) {
                   2034:         ABORT("GC_unprotect_range(range bigger than object)");
                   2035:     }
                   2036:     start_block = (struct hblk *)((word)addr & ~(GC_page_size - 1));
                   2037:     end_block = (struct hblk *)((word)(addr + len - 1) & ~(GC_page_size - 1));
                   2038:     end_block += GC_page_size/HBLKSIZE - 1;
                   2039:     for (h = start_block; h <= end_block; h++) {
                   2040:         register word index = PHT_HASH(h);
                   2041:
                   2042:         set_pht_entry_from_index(GC_dirty_pages, index);
                   2043:     }
                   2044:     UNPROTECT(start_block,
                   2045:              ((ptr_t)end_block - (ptr_t)start_block) + HBLKSIZE);
                   2046: }
                   2047:
                   2048: #ifndef MSWIN32
                   2049: /* Replacement for UNIX system call.    */
                   2050: /* Other calls that write to the heap   */
                   2051: /* should be handled similarly.                 */
                   2052: # if defined(__STDC__) && !defined(SUNOS4)
                   2053: #   include <unistd.h>
                   2054:     ssize_t read(int fd, void *buf, size_t nbyte)
                   2055: # else
                   2056: #   ifndef LINT
                   2057:       int read(fd, buf, nbyte)
                   2058: #   else
                   2059:       int GC_read(fd, buf, nbyte)
                   2060: #   endif
                   2061:     int fd;
                   2062:     char *buf;
                   2063:     int nbyte;
                   2064: # endif
                   2065: {
                   2066:     int result;
                   2067:
                   2068:     GC_begin_syscall();
                   2069:     GC_unprotect_range(buf, (word)nbyte);
                   2070: #   ifdef IRIX5
                   2071:        /* Indirect system call may not always be easily available.     */
                   2072:        /* We could call _read, but that would interfere with the       */
                   2073:        /* libpthread interception of read.                             */
                   2074:        {
                   2075:            struct iovec iov;
                   2076:
                   2077:            iov.iov_base = buf;
                   2078:            iov.iov_len = nbyte;
                   2079:            result = readv(fd, &iov, 1);
                   2080:        }
                   2081: #   else
                   2082:        result = syscall(SYS_read, fd, buf, nbyte);
                   2083: #   endif
                   2084:     GC_end_syscall();
                   2085:     return(result);
                   2086: }
                   2087: #endif /* !MSWIN32 */
                   2088:
                   2089: /*ARGSUSED*/
                   2090: GC_bool GC_page_was_ever_dirty(h)
                   2091: struct hblk *h;
                   2092: {
                   2093:     return(TRUE);
                   2094: }
                   2095:
                   2096: /* Reset the n pages starting at h to "was never dirty" status.        */
                   2097: /*ARGSUSED*/
                   2098: void GC_is_fresh(h, n)
                   2099: struct hblk *h;
                   2100: word n;
                   2101: {
                   2102: }
                   2103:
                   2104: # endif /* MPROTECT_VDB */
                   2105:
                   2106: # ifdef PROC_VDB
                   2107:
                   2108: /*
                   2109:  * See DEFAULT_VDB for interface descriptions.
                   2110:  */
                   2111:
                   2112: /*
                   2113:  * This implementaion assumes a Solaris 2.X like /proc pseudo-file-system
                   2114:  * from which we can read page modified bits.  This facility is far from
                   2115:  * optimal (e.g. we would like to get the info for only some of the
                   2116:  * address space), but it avoids intercepting system calls.
                   2117:  */
                   2118:
                   2119: #include <errno.h>
                   2120: #include <sys/types.h>
                   2121: #include <sys/signal.h>
                   2122: #include <sys/fault.h>
                   2123: #include <sys/syscall.h>
                   2124: #include <sys/procfs.h>
                   2125: #include <sys/stat.h>
                   2126: #include <fcntl.h>
                   2127:
                   2128: #define INITIAL_BUF_SZ 4096
                   2129: word GC_proc_buf_size = INITIAL_BUF_SZ;
                   2130: char *GC_proc_buf;
                   2131:
                   2132: #ifdef SOLARIS_THREADS
                   2133: /* We don't have exact sp values for threads.  So we count on  */
                   2134: /* occasionally declaring stack pages to be fresh.  Thus we    */
                   2135: /* need a real implementation of GC_is_fresh.  We can't clear  */
                   2136: /* entries in GC_written_pages, since that would declare all   */
                   2137: /* pages with the given hash address to be fresh.              */
                   2138: #   define MAX_FRESH_PAGES 8*1024      /* Must be power of 2 */
                   2139:     struct hblk ** GC_fresh_pages;     /* A direct mapped cache.       */
                   2140:                                        /* Collisions are dropped.      */
                   2141:
                   2142: #   define FRESH_PAGE_SLOT(h) (divHBLKSZ((word)(h)) & (MAX_FRESH_PAGES-1))
                   2143: #   define ADD_FRESH_PAGE(h) \
                   2144:        GC_fresh_pages[FRESH_PAGE_SLOT(h)] = (h)
                   2145: #   define PAGE_IS_FRESH(h) \
                   2146:        (GC_fresh_pages[FRESH_PAGE_SLOT(h)] == (h) && (h) != 0)
                   2147: #endif
                   2148:
                   2149: /* Add all pages in pht2 to pht1 */
                   2150: void GC_or_pages(pht1, pht2)
                   2151: page_hash_table pht1, pht2;
                   2152: {
                   2153:     register int i;
                   2154:
                   2155:     for (i = 0; i < PHT_SIZE; i++) pht1[i] |= pht2[i];
                   2156: }
                   2157:
                   2158: int GC_proc_fd;
                   2159:
                   2160: void GC_dirty_init()
                   2161: {
                   2162:     int fd;
                   2163:     char buf[30];
                   2164:
                   2165:     GC_dirty_maintained = TRUE;
                   2166:     if (GC_words_allocd != 0 || GC_words_allocd_before_gc != 0) {
                   2167:        register int i;
                   2168:
                   2169:         for (i = 0; i < PHT_SIZE; i++) GC_written_pages[i] = (word)(-1);
                   2170: #       ifdef PRINTSTATS
                   2171:            GC_printf1("Allocated words:%lu:all pages may have been written\n",
                   2172:                       (unsigned long)
                   2173:                                (GC_words_allocd + GC_words_allocd_before_gc));
                   2174: #      endif
                   2175:     }
                   2176:     sprintf(buf, "/proc/%d", getpid());
                   2177:     fd = open(buf, O_RDONLY);
                   2178:     if (fd < 0) {
                   2179:        ABORT("/proc open failed");
                   2180:     }
                   2181:     GC_proc_fd = syscall(SYS_ioctl, fd, PIOCOPENPD, 0);
                   2182:     close(fd);
                   2183:     if (GC_proc_fd < 0) {
                   2184:        ABORT("/proc ioctl failed");
                   2185:     }
                   2186:     GC_proc_buf = GC_scratch_alloc(GC_proc_buf_size);
                   2187: #   ifdef SOLARIS_THREADS
                   2188:        GC_fresh_pages = (struct hblk **)
                   2189:          GC_scratch_alloc(MAX_FRESH_PAGES * sizeof (struct hblk *));
                   2190:        if (GC_fresh_pages == 0) {
                   2191:            GC_err_printf0("No space for fresh pages\n");
                   2192:            EXIT();
                   2193:        }
                   2194:        BZERO(GC_fresh_pages, MAX_FRESH_PAGES * sizeof (struct hblk *));
                   2195: #   endif
                   2196: }
                   2197:
                   2198: /* Ignore write hints. They don't help us here.        */
                   2199: /*ARGSUSED*/
                   2200: void GC_write_hint(h)
                   2201: struct hblk *h;
                   2202: {
                   2203: }
                   2204:
                   2205: #ifdef SOLARIS_THREADS
                   2206: #   define READ(fd,buf,nbytes) syscall(SYS_read, fd, buf, nbytes)
                   2207: #else
                   2208: #   define READ(fd,buf,nbytes) read(fd, buf, nbytes)
                   2209: #endif
                   2210:
                   2211: void GC_read_dirty()
                   2212: {
                   2213:     unsigned long ps, np;
                   2214:     int nmaps;
                   2215:     ptr_t vaddr;
                   2216:     struct prasmap * map;
                   2217:     char * bufp;
                   2218:     ptr_t current_addr, limit;
                   2219:     int i;
                   2220: int dummy;
                   2221:
                   2222:     BZERO(GC_grungy_pages, (sizeof GC_grungy_pages));
                   2223:
                   2224:     bufp = GC_proc_buf;
                   2225:     if (READ(GC_proc_fd, bufp, GC_proc_buf_size) <= 0) {
                   2226: #      ifdef PRINTSTATS
                   2227:             GC_printf1("/proc read failed: GC_proc_buf_size = %lu\n",
                   2228:                       GC_proc_buf_size);
                   2229: #      endif
                   2230:         {
                   2231:             /* Retry with larger buffer. */
                   2232:             word new_size = 2 * GC_proc_buf_size;
                   2233:             char * new_buf = GC_scratch_alloc(new_size);
                   2234:
                   2235:             if (new_buf != 0) {
                   2236:                 GC_proc_buf = bufp = new_buf;
                   2237:                 GC_proc_buf_size = new_size;
                   2238:             }
                   2239:             if (syscall(SYS_read, GC_proc_fd, bufp, GC_proc_buf_size) <= 0) {
                   2240:                 WARN("Insufficient space for /proc read\n", 0);
                   2241:                 /* Punt:       */
                   2242:                memset(GC_grungy_pages, 0xff, sizeof (page_hash_table));
                   2243:                memset(GC_written_pages, 0xff, sizeof(page_hash_table));
                   2244: #              ifdef SOLARIS_THREADS
                   2245:                    BZERO(GC_fresh_pages,
                   2246:                          MAX_FRESH_PAGES * sizeof (struct hblk *));
                   2247: #              endif
                   2248:                return;
                   2249:             }
                   2250:         }
                   2251:     }
                   2252:     /* Copy dirty bits into GC_grungy_pages */
                   2253:        nmaps = ((struct prpageheader *)bufp) -> pr_nmap;
                   2254:        /* printf( "nmaps = %d, PG_REFERENCED = %d, PG_MODIFIED = %d\n",
                   2255:                     nmaps, PG_REFERENCED, PG_MODIFIED); */
                   2256:        bufp = bufp + sizeof(struct prpageheader);
                   2257:        for (i = 0; i < nmaps; i++) {
                   2258:            map = (struct prasmap *)bufp;
                   2259:            vaddr = (ptr_t)(map -> pr_vaddr);
                   2260:            ps = map -> pr_pagesize;
                   2261:            np = map -> pr_npage;
                   2262:            /* printf("vaddr = 0x%X, ps = 0x%X, np = 0x%X\n", vaddr, ps, np); */
                   2263:            limit = vaddr + ps * np;
                   2264:            bufp += sizeof (struct prasmap);
                   2265:            for (current_addr = vaddr;
                   2266:                 current_addr < limit; current_addr += ps){
                   2267:                if ((*bufp++) & PG_MODIFIED) {
                   2268:                    register struct hblk * h = (struct hblk *) current_addr;
                   2269:
                   2270:                    while ((ptr_t)h < current_addr + ps) {
                   2271:                        register word index = PHT_HASH(h);
                   2272:
                   2273:                        set_pht_entry_from_index(GC_grungy_pages, index);
                   2274: #                      ifdef SOLARIS_THREADS
                   2275:                          {
                   2276:                            register int slot = FRESH_PAGE_SLOT(h);
                   2277:
                   2278:                            if (GC_fresh_pages[slot] == h) {
                   2279:                                GC_fresh_pages[slot] = 0;
                   2280:                            }
                   2281:                          }
                   2282: #                      endif
                   2283:                        h++;
                   2284:                    }
                   2285:                }
                   2286:            }
                   2287:            bufp += sizeof(long) - 1;
                   2288:            bufp = (char *)((unsigned long)bufp & ~(sizeof(long)-1));
                   2289:        }
                   2290:     /* Update GC_written_pages. */
                   2291:         GC_or_pages(GC_written_pages, GC_grungy_pages);
                   2292: #   ifdef SOLARIS_THREADS
                   2293:       /* Make sure that old stacks are considered completely clean     */
                   2294:       /* unless written again.                                         */
                   2295:        GC_old_stacks_are_fresh();
                   2296: #   endif
                   2297: }
                   2298:
                   2299: #undef READ
                   2300:
                   2301: GC_bool GC_page_was_dirty(h)
                   2302: struct hblk *h;
                   2303: {
                   2304:     register word index = PHT_HASH(h);
                   2305:     register GC_bool result;
                   2306:
                   2307:     result = get_pht_entry_from_index(GC_grungy_pages, index);
                   2308: #   ifdef SOLARIS_THREADS
                   2309:        if (result && PAGE_IS_FRESH(h)) result = FALSE;
                   2310:        /* This happens only if page was declared fresh since   */
                   2311:        /* the read_dirty call, e.g. because it's in an unused  */
                   2312:        /* thread stack.  It's OK to treat it as clean, in      */
                   2313:        /* that case.  And it's consistent with                 */
                   2314:        /* GC_page_was_ever_dirty.                              */
                   2315: #   endif
                   2316:     return(result);
                   2317: }
                   2318:
                   2319: GC_bool GC_page_was_ever_dirty(h)
                   2320: struct hblk *h;
                   2321: {
                   2322:     register word index = PHT_HASH(h);
                   2323:     register GC_bool result;
                   2324:
                   2325:     result = get_pht_entry_from_index(GC_written_pages, index);
                   2326: #   ifdef SOLARIS_THREADS
                   2327:        if (result && PAGE_IS_FRESH(h)) result = FALSE;
                   2328: #   endif
                   2329:     return(result);
                   2330: }
                   2331:
                   2332: /* Caller holds allocation lock.       */
                   2333: void GC_is_fresh(h, n)
                   2334: struct hblk *h;
                   2335: word n;
                   2336: {
                   2337:
                   2338:     register word index;
                   2339:
                   2340: #   ifdef SOLARIS_THREADS
                   2341:       register word i;
                   2342:
                   2343:       if (GC_fresh_pages != 0) {
                   2344:         for (i = 0; i < n; i++) {
                   2345:           ADD_FRESH_PAGE(h + i);
                   2346:         }
                   2347:       }
                   2348: #   endif
                   2349: }
                   2350:
                   2351: # endif /* PROC_VDB */
                   2352:
                   2353:
                   2354: # ifdef PCR_VDB
                   2355:
                   2356: # include "vd/PCR_VD.h"
                   2357:
                   2358: # define NPAGES (32*1024)      /* 128 MB */
                   2359:
                   2360: PCR_VD_DB  GC_grungy_bits[NPAGES];
                   2361:
                   2362: ptr_t GC_vd_base;      /* Address corresponding to GC_grungy_bits[0]   */
                   2363:                        /* HBLKSIZE aligned.                            */
                   2364:
                   2365: void GC_dirty_init()
                   2366: {
                   2367:     GC_dirty_maintained = TRUE;
                   2368:     /* For the time being, we assume the heap generally grows up */
                   2369:     GC_vd_base = GC_heap_sects[0].hs_start;
                   2370:     if (GC_vd_base == 0) {
                   2371:        ABORT("Bad initial heap segment");
                   2372:     }
                   2373:     if (PCR_VD_Start(HBLKSIZE, GC_vd_base, NPAGES*HBLKSIZE)
                   2374:        != PCR_ERes_okay) {
                   2375:        ABORT("dirty bit initialization failed");
                   2376:     }
                   2377: }
                   2378:
                   2379: void GC_read_dirty()
                   2380: {
                   2381:     /* lazily enable dirty bits on newly added heap sects */
                   2382:     {
                   2383:         static int onhs = 0;
                   2384:         int nhs = GC_n_heap_sects;
                   2385:         for( ; onhs < nhs; onhs++ ) {
                   2386:             PCR_VD_WriteProtectEnable(
                   2387:                     GC_heap_sects[onhs].hs_start,
                   2388:                     GC_heap_sects[onhs].hs_bytes );
                   2389:         }
                   2390:     }
                   2391:
                   2392:
                   2393:     if (PCR_VD_Clear(GC_vd_base, NPAGES*HBLKSIZE, GC_grungy_bits)
                   2394:         != PCR_ERes_okay) {
                   2395:        ABORT("dirty bit read failed");
                   2396:     }
                   2397: }
                   2398:
                   2399: GC_bool GC_page_was_dirty(h)
                   2400: struct hblk *h;
                   2401: {
                   2402:     if((ptr_t)h < GC_vd_base || (ptr_t)h >= GC_vd_base + NPAGES*HBLKSIZE) {
                   2403:        return(TRUE);
                   2404:     }
                   2405:     return(GC_grungy_bits[h - (struct hblk *)GC_vd_base] & PCR_VD_DB_dirtyBit);
                   2406: }
                   2407:
                   2408: /*ARGSUSED*/
                   2409: void GC_write_hint(h)
                   2410: struct hblk *h;
                   2411: {
                   2412:     PCR_VD_WriteProtectDisable(h, HBLKSIZE);
                   2413:     PCR_VD_WriteProtectEnable(h, HBLKSIZE);
                   2414: }
                   2415:
                   2416: # endif /* PCR_VDB */
                   2417:
                   2418: /*
                   2419:  * Call stack save code for debugging.
                   2420:  * Should probably be in mach_dep.c, but that requires reorganization.
                   2421:  */
                   2422: #if defined(SPARC) && !defined(LINUX)
                   2423: #   if defined(SUNOS4)
                   2424: #     include <machine/frame.h>
                   2425: #   else
                   2426: #     if defined (DRSNX)
                   2427: #      include <sys/sparc/frame.h>
                   2428: #     else
                   2429: #        if defined(OPENBSD)
                   2430: #          include <frame.h>
                   2431: #        else
                   2432: #          include <sys/frame.h>
                   2433: #        endif
                   2434: #     endif
                   2435: #   endif
                   2436: #   if NARGS > 6
                   2437:        --> We only know how to to get the first 6 arguments
                   2438: #   endif
                   2439:
                   2440: #ifdef SAVE_CALL_CHAIN
                   2441: /* Fill in the pc and argument information for up to NFRAMES of my     */
                   2442: /* callers.  Ignore my frame and my callers frame.                     */
                   2443:
                   2444: #ifdef OPENBSD
                   2445: #  define FR_SAVFP fr_fp
                   2446: #  define FR_SAVPC fr_pc
                   2447: #else
                   2448: #  define FR_SAVFP fr_savfp
                   2449: #  define FR_SAVPC fr_savpc
                   2450: #endif
                   2451:
                   2452: void GC_save_callers (info)
                   2453: struct callinfo info[NFRAMES];
                   2454: {
                   2455:   struct frame *frame;
                   2456:   struct frame *fp;
                   2457:   int nframes = 0;
                   2458:   word GC_save_regs_in_stack();
                   2459:
                   2460:   frame = (struct frame *) GC_save_regs_in_stack ();
                   2461:
                   2462:   for (fp = frame -> FR_SAVFP; fp != 0 && nframes < NFRAMES;
                   2463:        fp = fp -> FR_SAVFP, nframes++) {
                   2464:       register int i;
                   2465:
                   2466:       info[nframes].ci_pc = fp->FR_SAVPC;
                   2467:       for (i = 0; i < NARGS; i++) {
                   2468:        info[nframes].ci_arg[i] = ~(fp->fr_arg[i]);
                   2469:       }
                   2470:   }
                   2471:   if (nframes < NFRAMES) info[nframes].ci_pc = 0;
                   2472: }
                   2473:
                   2474: #endif /* SAVE_CALL_CHAIN */
                   2475: #endif /* SPARC */
                   2476:
                   2477:
                   2478:

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