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[Emacs-diffs] Changes to emacs/gc/os_dep.c [Boehm-versions]
|
From: |
Dave Love |
|
Subject: |
[Emacs-diffs] Changes to emacs/gc/os_dep.c [Boehm-versions] |
|
Date: |
Mon, 16 Jun 2003 11:20:04 -0400 |
Index: emacs/gc/os_dep.c
diff -c /dev/null emacs/gc/os_dep.c:1.2.2.1.2.1
*** /dev/null Mon Jun 16 11:20:04 2003
--- emacs/gc/os_dep.c Mon Jun 16 11:19:52 2003
***************
*** 0 ****
--- 1,4119 ----
+ /*
+ * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
+ * Copyright (c) 1991-1995 by Xerox Corporation. All rights reserved.
+ * Copyright (c) 1996-1999 by Silicon Graphics. All rights reserved.
+ * Copyright (c) 1999 by Hewlett-Packard Company. All rights reserved.
+ *
+ * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
+ * OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
+ *
+ * Permission is hereby granted to use or copy this program
+ * for any purpose, provided the above notices are retained on all copies.
+ * Permission to modify the code and to distribute modified code is granted,
+ * provided the above notices are retained, and a notice that the code was
+ * modified is included with the above copyright notice.
+ */
+
+ # include "private/gc_priv.h"
+
+ # if defined(LINUX) && !defined(POWERPC)
+ # include <linux/version.h>
+ # if (LINUX_VERSION_CODE <= 0x10400)
+ /* Ugly hack to get struct sigcontext_struct definition. Required
*/
+ /* for some early 1.3.X releases. Will hopefully go away soon. */
+ /* in some later Linux releases, asm/sigcontext.h may have to */
+ /* be included instead. */
+ # define __KERNEL__
+ # include <asm/signal.h>
+ # undef __KERNEL__
+ # else
+ /* Kernels prior to 2.1.1 defined struct sigcontext_struct instead of */
+ /* struct sigcontext. libc6 (glibc2) uses "struct sigcontext" in */
+ /* prototypes, so we have to include the top-level sigcontext.h to */
+ /* make sure the former gets defined to be the latter if appropriate. */
+ # include <features.h>
+ # if 2 <= __GLIBC__
+ # if 2 == __GLIBC__ && 0 == __GLIBC_MINOR__
+ /* glibc 2.1 no longer has sigcontext.h. But signal.h */
+ /* has the right declaration for glibc 2.1. */
+ # include <sigcontext.h>
+ # endif /* 0 == __GLIBC_MINOR__ */
+ # else /* not 2 <= __GLIBC__ */
+ /* libc5 doesn't have <sigcontext.h>: go directly with the kernel */
+ /* one. Check LINUX_VERSION_CODE to see which we should reference. */
+ # include <asm/sigcontext.h>
+ # endif /* 2 <= __GLIBC__ */
+ # endif
+ # endif
+ # if !defined(OS2) && !defined(PCR) && !defined(AMIGA) && !defined(MACOS) \
+ && !defined(MSWINCE)
+ # include <sys/types.h>
+ # if !defined(MSWIN32) && !defined(SUNOS4)
+ # include <unistd.h>
+ # endif
+ # endif
+
+ # include <stdio.h>
+ # if defined(MSWINCE)
+ # define SIGSEGV 0 /* value is irrelevant */
+ # else
+ # include <signal.h>
+ # endif
+
+ /* Blatantly OS dependent routines, except for those that are related
*/
+ /* to dynamic loading.
*/
+
+ # if defined(HEURISTIC2) || defined(SEARCH_FOR_DATA_START)
+ # define NEED_FIND_LIMIT
+ # endif
+
+ # if !defined(STACKBOTTOM) && defined(HEURISTIC2)
+ # define NEED_FIND_LIMIT
+ # endif
+
+ # if (defined(SUNOS4) && defined(DYNAMIC_LOADING)) && !defined(PCR)
+ # define NEED_FIND_LIMIT
+ # endif
+
+ # if (defined(SVR4) || defined(AUX) || defined(DGUX) \
+ || (defined(LINUX) && defined(SPARC))) && !defined(PCR)
+ # define NEED_FIND_LIMIT
+ # endif
+
+ #if defined(FREEBSD) && defined(I386)
+ # include <machine/trap.h>
+ # if !defined(PCR)
+ # define NEED_FIND_LIMIT
+ # endif
+ #endif
+
+ #ifdef NEED_FIND_LIMIT
+ # include <setjmp.h>
+ #endif
+
+ #ifdef AMIGA
+ # define GC_AMIGA_DEF
+ # include "AmigaOS.c"
+ # undef GC_AMIGA_DEF
+ #endif
+
+ #if defined(MSWIN32) || defined(MSWINCE)
+ # define WIN32_LEAN_AND_MEAN
+ # define NOSERVICE
+ # include <windows.h>
+ #endif
+
+ #ifdef MACOS
+ # include <Processes.h>
+ #endif
+
+ #ifdef IRIX5
+ # include <sys/uio.h>
+ # include <malloc.h> /* for locking */
+ #endif
+ #ifdef USE_MMAP
+ # include <sys/types.h>
+ # include <sys/mman.h>
+ # include <sys/stat.h>
+ #endif
+
+ #ifdef UNIX_LIKE
+ # include <fcntl.h>
+ #endif
+
+ #if defined(SUNOS5SIGS) || defined (HURD) || defined(LINUX)
+ # ifdef SUNOS5SIGS
+ # include <sys/siginfo.h>
+ # endif
+ # undef setjmp
+ # undef longjmp
+ # define setjmp(env) sigsetjmp(env, 1)
+ # define longjmp(env, val) siglongjmp(env, val)
+ # define jmp_buf sigjmp_buf
+ #endif
+
+ #ifdef DARWIN
+ /* for get_etext and friends */
+ #include <mach-o/getsect.h>
+ #endif
+
+ #ifdef DJGPP
+ /* Apparently necessary for djgpp 2.01. May cause problems with */
+ /* other versions. */
+ typedef long unsigned int caddr_t;
+ #endif
+
+ #ifdef PCR
+ # include "il/PCR_IL.h"
+ # include "th/PCR_ThCtl.h"
+ # include "mm/PCR_MM.h"
+ #endif
+
+ #if !defined(NO_EXECUTE_PERMISSION)
+ # define OPT_PROT_EXEC PROT_EXEC
+ #else
+ # define OPT_PROT_EXEC 0
+ #endif
+
+ #if defined(LINUX) && \
+ (defined(USE_PROC_FOR_LIBRARIES) || defined(IA64) ||
!defined(SMALL_CONFIG))
+
+ /* We need to parse /proc/self/maps, either to find dynamic libraries,
*/
+ /* and/or to find the register backing store base (IA64). Do it once */
+ /* here. */
+
+ #define READ read
+
+ /* Repeatedly perform a read call until the buffer is filled or */
+ /* we encounter EOF. */
+ ssize_t GC_repeat_read(int fd, char *buf, size_t count)
+ {
+ ssize_t num_read = 0;
+ ssize_t result;
+
+ while (num_read < count) {
+ result = READ(fd, buf + num_read, count - num_read);
+ if (result < 0) return result;
+ if (result == 0) break;
+ num_read += result;
+ }
+ return num_read;
+ }
+
+ /*
+ * Apply fn to a buffer containing the contents of /proc/self/maps.
+ * Return the result of fn or, if we failed, 0.
+ */
+
+ word GC_apply_to_maps(word (*fn)(char *))
+ {
+ int f;
+ int result;
+ int maps_size;
+ char maps_temp[32768];
+ char *maps_buf;
+
+ /* Read /proc/self/maps */
+ /* Note that we may not allocate, and thus can't use stdio. */
+ f = open("/proc/self/maps", O_RDONLY);
+ if (-1 == f) return 0;
+ /* stat() doesn't work for /proc/self/maps, so we have to
+ read it to find out how large it is... */
+ maps_size = 0;
+ do {
+ result = GC_repeat_read(f, maps_temp, sizeof(maps_temp));
+ if (result <= 0) return 0;
+ maps_size += result;
+ } while (result == sizeof(maps_temp));
+
+ if (maps_size > sizeof(maps_temp)) {
+ /* If larger than our buffer, close and re-read it. */
+ close(f);
+ f = open("/proc/self/maps", O_RDONLY);
+ if (-1 == f) return 0;
+ maps_buf = alloca(maps_size);
+ if (NULL == maps_buf) return 0;
+ result = GC_repeat_read(f, maps_buf, maps_size);
+ if (result <= 0) return 0;
+ } else {
+ /* Otherwise use the fixed size buffer */
+ maps_buf = maps_temp;
+ }
+
+ close(f);
+ maps_buf[result] = '\0';
+
+ /* Apply fn to result. */
+ return fn(maps_buf);
+ }
+
+ #endif /* Need GC_apply_to_maps */
+
+ #if defined(LINUX) && (defined(USE_PROC_FOR_LIBRARIES) || defined(IA64))
+ //
+ // GC_parse_map_entry parses an entry from /proc/self/maps so we can
+ // locate all writable data segments that belong to shared libraries.
+ // The format of one of these entries and the fields we care about
+ // is as follows:
+ // XXXXXXXX-XXXXXXXX r-xp 00000000 30:05 260537 name of mapping...\n
+ // ^^^^^^^^ ^^^^^^^^ ^^^^ ^^
+ // start end prot maj_dev
+ // 0 9 18 32
+ //
+ // For 64 bit ABIs:
+ // 0 17 34 56
+ //
+ // The parser is called with a pointer to the entry and the return value
+ // is either NULL or is advanced to the next entry(the byte after the
+ // trailing '\n'.)
+ //
+ #if CPP_WORDSZ == 32
+ # define OFFSET_MAP_START 0
+ # define OFFSET_MAP_END 9
+ # define OFFSET_MAP_PROT 18
+ # define OFFSET_MAP_MAJDEV 32
+ # define ADDR_WIDTH 8
+ #endif
+
+ #if CPP_WORDSZ == 64
+ # define OFFSET_MAP_START 0
+ # define OFFSET_MAP_END 17
+ # define OFFSET_MAP_PROT 34
+ # define OFFSET_MAP_MAJDEV 56
+ # define ADDR_WIDTH 16
+ #endif
+
+ /*
+ * Assign various fields of the first line in buf_ptr to *start, *end,
+ * *prot_buf and *maj_dev. Only *prot_buf may be set for unwritable maps.
+ */
+ char *GC_parse_map_entry(char *buf_ptr, word *start, word *end,
+ char *prot_buf, unsigned int *maj_dev)
+ {
+ int i;
+ char *tok;
+
+ if (buf_ptr == NULL || *buf_ptr == '\0') {
+ return NULL;
+ }
+
+ memcpy(prot_buf, buf_ptr+OFFSET_MAP_PROT, 4);
+ /* do the protections first. */
+ prot_buf[4] = '\0';
+
+ if (prot_buf[1] == 'w') {/* we can skip all of this if it's not writable.
*/
+
+ tok = buf_ptr;
+ buf_ptr[OFFSET_MAP_START+ADDR_WIDTH] = '\0';
+ *start = strtoul(tok, NULL, 16);
+
+ tok = buf_ptr+OFFSET_MAP_END;
+ buf_ptr[OFFSET_MAP_END+ADDR_WIDTH] = '\0';
+ *end = strtoul(tok, NULL, 16);
+
+ buf_ptr += OFFSET_MAP_MAJDEV;
+ tok = buf_ptr;
+ while (*buf_ptr != ':') buf_ptr++;
+ *buf_ptr++ = '\0';
+ *maj_dev = strtoul(tok, NULL, 16);
+ }
+
+ while (*buf_ptr && *buf_ptr++ != '\n');
+
+ return buf_ptr;
+ }
+
+ #endif /* Need to parse /proc/self/maps. */
+
+ #if defined(SEARCH_FOR_DATA_START)
+ /* The I386 case can be handled without a search. The Alpha case */
+ /* used to be handled differently as well, but the rules changed */
+ /* for recent Linux versions. This seems to be the easiest way to */
+ /* cover all versions. */
+
+ # ifdef LINUX
+ /* Some Linux distributions arrange to define __data_start. Some */
+ /* define data_start as a weak symbol. The latter is technically */
+ /* broken, since the user program may define data_start, in which */
+ /* case we lose. Nonetheless, we try both, prefering __data_start.
*/
+ /* We assume gcc-compatible pragmas. */
+ # pragma weak __data_start
+ extern int __data_start[];
+ # pragma weak data_start
+ extern int data_start[];
+ # endif /* LINUX */
+ extern int _end[];
+
+ ptr_t GC_data_start;
+
+ void GC_init_linux_data_start()
+ {
+ extern ptr_t GC_find_limit();
+
+ # ifdef LINUX
+ /* Try the easy approaches first: */
+ if ((ptr_t)__data_start != 0) {
+ GC_data_start = (ptr_t)(__data_start);
+ return;
+ }
+ if ((ptr_t)data_start != 0) {
+ GC_data_start = (ptr_t)(data_start);
+ return;
+ }
+ # endif /* LINUX */
+ GC_data_start = GC_find_limit((ptr_t)(_end), FALSE);
+ }
+ #endif
+
+ # ifdef ECOS
+
+ # ifndef ECOS_GC_MEMORY_SIZE
+ # define ECOS_GC_MEMORY_SIZE (448 * 1024)
+ # endif /* ECOS_GC_MEMORY_SIZE */
+
+ // setjmp() function, as described in ANSI para 7.6.1.1
+ #define setjmp( __env__ ) hal_setjmp( __env__ )
+
+ // FIXME: This is a simple way of allocating memory which is
+ // compatible with ECOS early releases. Later releases use a more
+ // sophisticated means of allocating memory than this simple static
+ // allocator, but this method is at least bound to work.
+ static char memory[ECOS_GC_MEMORY_SIZE];
+ static char *brk = memory;
+
+ static void *tiny_sbrk(ptrdiff_t increment)
+ {
+ void *p = brk;
+
+ brk += increment;
+
+ if (brk > memory + sizeof memory)
+ {
+ brk -= increment;
+ return NULL;
+ }
+
+ return p;
+ }
+ #define sbrk tiny_sbrk
+ # endif /* ECOS */
+
+ #if (defined(NETBSD) || defined(OPENBSD)) && defined(__ELF__)
+ ptr_t GC_data_start;
+
+ void GC_init_netbsd_elf()
+ {
+ extern ptr_t GC_find_limit();
+ extern char **environ;
+ /* This may need to be environ, without the underscore, for */
+ /* some versions. */
+ GC_data_start = GC_find_limit((ptr_t)&environ, FALSE);
+ }
+ #endif
+
+ # ifdef OS2
+
+ # include <stddef.h>
+
+ # if !defined(__IBMC__) && !defined(__WATCOMC__) /* e.g. EMX */
+
+ struct exe_hdr {
+ unsigned short magic_number;
+ unsigned short padding[29];
+ long new_exe_offset;
+ };
+
+ #define E_MAGIC(x) (x).magic_number
+ #define EMAGIC 0x5A4D
+ #define E_LFANEW(x) (x).new_exe_offset
+
+ struct e32_exe {
+ unsigned char magic_number[2];
+ unsigned char byte_order;
+ unsigned char word_order;
+ unsigned long exe_format_level;
+ unsigned short cpu;
+ unsigned short os;
+ unsigned long padding1[13];
+ unsigned long object_table_offset;
+ unsigned long object_count;
+ unsigned long padding2[31];
+ };
+
+ #define E32_MAGIC1(x) (x).magic_number[0]
+ #define E32MAGIC1 'L'
+ #define E32_MAGIC2(x) (x).magic_number[1]
+ #define E32MAGIC2 'X'
+ #define E32_BORDER(x) (x).byte_order
+ #define E32LEBO 0
+ #define E32_WORDER(x) (x).word_order
+ #define E32LEWO 0
+ #define E32_CPU(x) (x).cpu
+ #define E32CPU286 1
+ #define E32_OBJTAB(x) (x).object_table_offset
+ #define E32_OBJCNT(x) (x).object_count
+
+ struct o32_obj {
+ unsigned long size;
+ unsigned long base;
+ unsigned long flags;
+ unsigned long pagemap;
+ unsigned long mapsize;
+ unsigned long reserved;
+ };
+
+ #define O32_FLAGS(x) (x).flags
+ #define OBJREAD 0x0001L
+ #define OBJWRITE 0x0002L
+ #define OBJINVALID 0x0080L
+ #define O32_SIZE(x) (x).size
+ #define O32_BASE(x) (x).base
+
+ # else /* IBM's compiler */
+
+ /* A kludge to get around what appears to be a header file bug */
+ # ifndef WORD
+ # define WORD unsigned short
+ # endif
+ # ifndef DWORD
+ # define DWORD unsigned long
+ # endif
+
+ # define EXE386 1
+ # include <newexe.h>
+ # include <exe386.h>
+
+ # endif /* __IBMC__ */
+
+ # define INCL_DOSEXCEPTIONS
+ # define INCL_DOSPROCESS
+ # define INCL_DOSERRORS
+ # define INCL_DOSMODULEMGR
+ # define INCL_DOSMEMMGR
+ # include <os2.h>
+
+
+ /* Disable and enable signals during nontrivial allocations */
+
+ void GC_disable_signals(void)
+ {
+ ULONG nest;
+
+ DosEnterMustComplete(&nest);
+ if (nest != 1) ABORT("nested GC_disable_signals");
+ }
+
+ void GC_enable_signals(void)
+ {
+ ULONG nest;
+
+ DosExitMustComplete(&nest);
+ if (nest != 0) ABORT("GC_enable_signals");
+ }
+
+
+ # else
+
+ # if !defined(PCR) && !defined(AMIGA) && !defined(MSWIN32) \
+ && !defined(MSWINCE) \
+ && !defined(MACOS) && !defined(DJGPP) && !defined(DOS4GW) \
+ && !defined(NOSYS) && !defined(ECOS)
+
+ # if defined(sigmask) && !defined(UTS4) && !defined(HURD)
+ /* Use the traditional BSD interface */
+ # define SIGSET_T int
+ # define SIG_DEL(set, signal) (set) &= ~(sigmask(signal))
+ # define SIG_FILL(set) (set) = 0x7fffffff
+ /* Setting the leading bit appears to provoke a bug in some */
+ /* longjmp implementations. Most systems appear not to have */
+ /* a signal 32. */
+ # define SIGSETMASK(old, new) (old) = sigsetmask(new)
+ # else
+ /* Use POSIX/SYSV interface */
+ # define SIGSET_T sigset_t
+ # define SIG_DEL(set, signal) sigdelset(&(set), (signal))
+ # define SIG_FILL(set) sigfillset(&set)
+ # define SIGSETMASK(old, new) sigprocmask(SIG_SETMASK, &(new), &(old))
+ # endif
+
+ static GC_bool mask_initialized = FALSE;
+
+ static SIGSET_T new_mask;
+
+ static SIGSET_T old_mask;
+
+ static SIGSET_T dummy;
+
+ #if defined(PRINTSTATS) && !defined(THREADS)
+ # define CHECK_SIGNALS
+ int GC_sig_disabled = 0;
+ #endif
+
+ void GC_disable_signals()
+ {
+ if (!mask_initialized) {
+ SIG_FILL(new_mask);
+
+ SIG_DEL(new_mask, SIGSEGV);
+ SIG_DEL(new_mask, SIGILL);
+ SIG_DEL(new_mask, SIGQUIT);
+ # ifdef SIGBUS
+ SIG_DEL(new_mask, SIGBUS);
+ # endif
+ # ifdef SIGIOT
+ SIG_DEL(new_mask, SIGIOT);
+ # endif
+ # ifdef SIGEMT
+ SIG_DEL(new_mask, SIGEMT);
+ # endif
+ # ifdef SIGTRAP
+ SIG_DEL(new_mask, SIGTRAP);
+ # endif
+ mask_initialized = TRUE;
+ }
+ # ifdef CHECK_SIGNALS
+ if (GC_sig_disabled != 0) ABORT("Nested disables");
+ GC_sig_disabled++;
+ # endif
+ SIGSETMASK(old_mask,new_mask);
+ }
+
+ void GC_enable_signals()
+ {
+ # ifdef CHECK_SIGNALS
+ if (GC_sig_disabled != 1) ABORT("Unmatched enable");
+ GC_sig_disabled--;
+ # endif
+ SIGSETMASK(dummy,old_mask);
+ }
+
+ # endif /* !PCR */
+
+ # endif /*!OS/2 */
+
+ /* Ivan Demakov: simplest way (to me) */
+ #if defined (DOS4GW)
+ void GC_disable_signals() { }
+ void GC_enable_signals() { }
+ #endif
+
+ /* Find the page size */
+ word GC_page_size;
+
+ # if defined(MSWIN32) || defined(MSWINCE)
+ void GC_setpagesize()
+ {
+ GetSystemInfo(&GC_sysinfo);
+ GC_page_size = GC_sysinfo.dwPageSize;
+ }
+
+ # else
+ # if defined(MPROTECT_VDB) || defined(PROC_VDB) || defined(USE_MMAP) \
+ || defined(USE_MUNMAP)
+ void GC_setpagesize()
+ {
+ GC_page_size = GETPAGESIZE();
+ }
+ # else
+ /* It's acceptable to fake it. */
+ void GC_setpagesize()
+ {
+ GC_page_size = HBLKSIZE;
+ }
+ # endif
+ # endif
+
+ /*
+ * Find the base of the stack.
+ * Used only in single-threaded environment.
+ * With threads, GC_mark_roots needs to know how to do this.
+ * Called with allocator lock held.
+ */
+ # if defined(MSWIN32) || defined(MSWINCE)
+ # define is_writable(prot) ((prot) == PAGE_READWRITE \
+ || (prot) == PAGE_WRITECOPY \
+ || (prot) == PAGE_EXECUTE_READWRITE \
+ || (prot) == PAGE_EXECUTE_WRITECOPY)
+ /* Return the number of bytes that are writable starting at p. */
+ /* The pointer p is assumed to be page aligned. */
+ /* If base is not 0, *base becomes the beginning of the */
+ /* allocation region containing p. */
+ word GC_get_writable_length(ptr_t p, ptr_t *base)
+ {
+ MEMORY_BASIC_INFORMATION buf;
+ word result;
+ word protect;
+
+ result = VirtualQuery(p, &buf, sizeof(buf));
+ if (result != sizeof(buf)) ABORT("Weird VirtualQuery result");
+ if (base != 0) *base = (ptr_t)(buf.AllocationBase);
+ protect = (buf.Protect & ~(PAGE_GUARD | PAGE_NOCACHE));
+ if (!is_writable(protect)) {
+ return(0);
+ }
+ if (buf.State != MEM_COMMIT) return(0);
+ return(buf.RegionSize);
+ }
+
+ ptr_t GC_get_stack_base()
+ {
+ int dummy;
+ ptr_t sp = (ptr_t)(&dummy);
+ ptr_t trunc_sp = (ptr_t)((word)sp & ~(GC_page_size - 1));
+ word size = GC_get_writable_length(trunc_sp, 0);
+
+ return(trunc_sp + size);
+ }
+
+
+ # endif /* MS Windows */
+
+ # ifdef BEOS
+ # include <kernel/OS.h>
+ ptr_t GC_get_stack_base(){
+ thread_info th;
+ get_thread_info(find_thread(NULL),&th);
+ return th.stack_end;
+ }
+ # endif /* BEOS */
+
+
+ # ifdef OS2
+
+ ptr_t GC_get_stack_base()
+ {
+ PTIB ptib;
+ PPIB ppib;
+
+ if (DosGetInfoBlocks(&ptib, &ppib) != NO_ERROR) {
+ GC_err_printf0("DosGetInfoBlocks failed\n");
+ ABORT("DosGetInfoBlocks failed\n");
+ }
+ return((ptr_t)(ptib -> tib_pstacklimit));
+ }
+
+ # endif /* OS2 */
+
+ # ifdef AMIGA
+ # define GC_AMIGA_SB
+ # include "AmigaOS.c"
+ # undef GC_AMIGA_SB
+ # endif /* AMIGA */
+
+ # if defined(NEED_FIND_LIMIT) || defined(UNIX_LIKE)
+
+ # ifdef __STDC__
+ typedef void (*handler)(int);
+ # else
+ typedef void (*handler)();
+ # endif
+
+ # if defined(SUNOS5SIGS) || defined(IRIX5) || defined(OSF1) || defined(HURD)
+ static struct sigaction old_segv_act;
+ # if defined(_sigargs) /* !Irix6.x */ || defined(HPUX) || defined(HURD)
+ static struct sigaction old_bus_act;
+ # endif
+ # else
+ static handler old_segv_handler, old_bus_handler;
+ # endif
+
+ # ifdef __STDC__
+ void GC_set_and_save_fault_handler(handler h)
+ # else
+ void GC_set_and_save_fault_handler(h)
+ handler h;
+ # endif
+ {
+ # if defined(SUNOS5SIGS) || defined(IRIX5) \
+ || defined(OSF1) || defined(HURD)
+ struct sigaction act;
+
+ act.sa_handler = h;
+ # ifdef SUNOS5SIGS
+ act.sa_flags = SA_RESTART | SA_NODEFER;
+ # else
+ act.sa_flags = SA_RESTART;
+ # endif
+ /* The presence of SA_NODEFER represents yet another gross */
+ /* hack. Under Solaris 2.3, siglongjmp doesn't appear to */
+ /* interact correctly with -lthread. We hide the confusion */
+ /* by making sure that signal handling doesn't affect the */
+ /* signal mask. */
+
+ (void) sigemptyset(&act.sa_mask);
+ # ifdef GC_IRIX_THREADS
+ /* Older versions have a bug related to retrieving and */
+ /* and setting a handler at the same time. */
+ (void) sigaction(SIGSEGV, 0, &old_segv_act);
+ (void) sigaction(SIGSEGV, &act, 0);
+ # else
+ (void) sigaction(SIGSEGV, &act, &old_segv_act);
+ # if defined(IRIX5) && defined(_sigargs) /* Irix 5.x, not 6.x */ \
+ || defined(HPUX) || defined(HURD)
+ /* Under Irix 5.x or HP/UX, we may get SIGBUS. */
+ /* Pthreads doesn't exist under Irix 5.x, so we */
+ /* don't have to worry in the threads case. */
+ (void) sigaction(SIGBUS, &act, &old_bus_act);
+ # endif
+ # endif /* GC_IRIX_THREADS */
+ # else
+ old_segv_handler = signal(SIGSEGV, h);
+ # ifdef SIGBUS
+ old_bus_handler = signal(SIGBUS, h);
+ # endif
+ # endif
+ }
+ # endif /* NEED_FIND_LIMIT || UNIX_LIKE */
+
+ # ifdef NEED_FIND_LIMIT
+ /* Some tools to implement HEURISTIC2 */
+ # define MIN_PAGE_SIZE 256 /* Smallest conceivable page size, bytes */
+ /* static */ jmp_buf GC_jmp_buf;
+
+ /*ARGSUSED*/
+ void GC_fault_handler(sig)
+ int sig;
+ {
+ longjmp(GC_jmp_buf, 1);
+ }
+
+ void GC_setup_temporary_fault_handler()
+ {
+ GC_set_and_save_fault_handler(GC_fault_handler);
+ }
+
+ void GC_reset_fault_handler()
+ {
+ # if defined(SUNOS5SIGS) || defined(IRIX5) \
+ || defined(OSF1) || defined(HURD)
+ (void) sigaction(SIGSEGV, &old_segv_act, 0);
+ # if defined(IRIX5) && defined(_sigargs) /* Irix 5.x, not 6.x */ \
+ || defined(HPUX) || defined(HURD)
+ (void) sigaction(SIGBUS, &old_bus_act, 0);
+ # endif
+ # else
+ (void) signal(SIGSEGV, old_segv_handler);
+ # ifdef SIGBUS
+ (void) signal(SIGBUS, old_bus_handler);
+ # endif
+ # endif
+ }
+
+ /* Return the first nonaddressible location > p (up) or */
+ /* the smallest location q s.t. [q,p) is addressable (!up). */
+ /* We assume that p (up) or p-1 (!up) is addressable. */
+ ptr_t GC_find_limit(p, up)
+ ptr_t p;
+ GC_bool up;
+ {
+ static VOLATILE ptr_t result;
+ /* Needs to be static, since otherwise it may not be */
+ /* preserved across the longjmp. Can safely be */
+ /* static since it's only called once, with the */
+ /* allocation lock held. */
+
+
+ GC_setup_temporary_fault_handler();
+ if (setjmp(GC_jmp_buf) == 0) {
+ result = (ptr_t)(((word)(p))
+ & ~(MIN_PAGE_SIZE-1));
+ for (;;) {
+ if (up) {
+ result += MIN_PAGE_SIZE;
+ } else {
+ result -= MIN_PAGE_SIZE;
+ }
+ GC_noop1((word)(*result));
+ }
+ }
+ GC_reset_fault_handler();
+ if (!up) {
+ result += MIN_PAGE_SIZE;
+ }
+ return(result);
+ }
+ # endif
+
+ #if defined(ECOS) || defined(NOSYS)
+ ptr_t GC_get_stack_base()
+ {
+ return STACKBOTTOM;
+ }
+ #endif
+
+ #ifdef LINUX_STACKBOTTOM
+
+ #include <sys/types.h>
+ #include <sys/stat.h>
+ #include <ctype.h>
+
+ # define STAT_SKIP 27 /* Number of fields preceding startstack */
+ /* field in /proc/self/stat */
+
+ # pragma weak __libc_stack_end
+ extern ptr_t __libc_stack_end;
+
+ # ifdef IA64
+ /* Try to read the backing store base from /proc/self/maps. */
+ /* We look for the writable mapping with a 0 major device, */
+ /* which is as close to our frame as possible, but below it.*/
+ static word backing_store_base_from_maps(char *maps)
+ {
+ char prot_buf[5];
+ char *buf_ptr = maps;
+ word start, end;
+ unsigned int maj_dev;
+ word current_best = 0;
+ word dummy;
+
+ for (;;) {
+ buf_ptr = GC_parse_map_entry(buf_ptr, &start, &end, prot_buf,
&maj_dev);
+ if (buf_ptr == NULL) return current_best;
+ if (prot_buf[1] == 'w' && maj_dev == 0) {
+ if (end < (word)(&dummy) && start > current_best) current_best =
start;
+ }
+ }
+ return current_best;
+ }
+
+ static word backing_store_base_from_proc(void)
+ {
+ return GC_apply_to_maps(backing_store_base_from_maps);
+ }
+
+ # pragma weak __libc_ia64_register_backing_store_base
+ extern ptr_t __libc_ia64_register_backing_store_base;
+
+ ptr_t GC_get_register_stack_base(void)
+ {
+ if (0 != &__libc_ia64_register_backing_store_base
+ && 0 != __libc_ia64_register_backing_store_base) {
+ /* Glibc 2.2.4 has a bug such that for dynamically linked */
+ /* executables __libc_ia64_register_backing_store_base is */
+ /* defined but uninitialized during constructor calls. */
+ /* Hence we check for both nonzero address and value. */
+ return __libc_ia64_register_backing_store_base;
+ } else {
+ word result = backing_store_base_from_proc();
+ if (0 == result) {
+ /* Use dumb heuristics. Works only for default configuration. */
+ result = (word)GC_stackbottom - BACKING_STORE_DISPLACEMENT;
+ result += BACKING_STORE_ALIGNMENT - 1;
+ result &= ~(BACKING_STORE_ALIGNMENT - 1);
+ /* Verify that it's at least readable. If not, we goofed. */
+ GC_noop1(*(word *)result);
+ }
+ return (ptr_t)result;
+ }
+ }
+ # endif
+
+ ptr_t GC_linux_stack_base(void)
+ {
+ /* We read the stack base value from /proc/self/stat. We do this */
+ /* using direct I/O system calls in order to avoid calling malloc */
+ /* in case REDIRECT_MALLOC is defined. */
+ # define STAT_BUF_SIZE 4096
+ # define STAT_READ read
+ /* Should probably call the real read, if read is wrapped. */
+ char stat_buf[STAT_BUF_SIZE];
+ int f;
+ char c;
+ word result = 0;
+ size_t i, buf_offset = 0;
+
+ /* First try the easy way. This should work for glibc 2.2 */
+ if (0 != &__libc_stack_end) {
+ # ifdef IA64
+ /* Some versions of glibc set the address 16 bytes too */
+ /* low while the initialization code is running. */
+ if (((word)__libc_stack_end & 0xfff) + 0x10 < 0x1000) {
+ return __libc_stack_end + 0x10;
+ } /* Otherwise it's not safe to add 16 bytes and we fall */
+ /* back to using /proc. */
+ # else
+ return __libc_stack_end;
+ # endif
+ }
+ f = open("/proc/self/stat", O_RDONLY);
+ if (f < 0 || STAT_READ(f, stat_buf, STAT_BUF_SIZE) < 2 * STAT_SKIP) {
+ ABORT("Couldn't read /proc/self/stat");
+ }
+ c = stat_buf[buf_offset++];
+ /* Skip the required number of fields. This number is hopefully */
+ /* constant across all Linux implementations. */
+ for (i = 0; i < STAT_SKIP; ++i) {
+ while (isspace(c)) c = stat_buf[buf_offset++];
+ while (!isspace(c)) c = stat_buf[buf_offset++];
+ }
+ while (isspace(c)) c = stat_buf[buf_offset++];
+ while (isdigit(c)) {
+ result *= 10;
+ result += c - '0';
+ c = stat_buf[buf_offset++];
+ }
+ close(f);
+ if (result < 0x10000000) ABORT("Absurd stack bottom value");
+ return (ptr_t)result;
+ }
+
+ #endif /* LINUX_STACKBOTTOM */
+
+ #ifdef FREEBSD_STACKBOTTOM
+
+ /* This uses an undocumented sysctl call, but at least one expert */
+ /* believes it will stay. */
+
+ #include <unistd.h>
+ #include <sys/types.h>
+ #include <sys/sysctl.h>
+
+ ptr_t GC_freebsd_stack_base(void)
+ {
+ int nm[2] = {CTL_KERN, KERN_USRSTACK};
+ ptr_t base;
+ size_t len = sizeof(ptr_t);
+ int r = sysctl(nm, 2, &base, &len, NULL, 0);
+
+ if (r) ABORT("Error getting stack base");
+
+ return base;
+ }
+
+ #endif /* FREEBSD_STACKBOTTOM */
+
+ #if !defined(BEOS) && !defined(AMIGA) && !defined(MSWIN32) \
+ && !defined(MSWINCE) && !defined(OS2)
+
+ ptr_t GC_get_stack_base()
+ {
+ # if defined(HEURISTIC1) || defined(HEURISTIC2) || \
+ defined(LINUX_STACKBOTTOM) || defined(FREEBSD_STACKBOTTOM)
+ word dummy;
+ ptr_t result;
+ # endif
+
+ # define STACKBOTTOM_ALIGNMENT_M1 ((word)STACK_GRAN - 1)
+
+ # ifdef STACKBOTTOM
+ return(STACKBOTTOM);
+ # else
+ # ifdef HEURISTIC1
+ # ifdef STACK_GROWS_DOWN
+ result = (ptr_t)((((word)(&dummy))
+ + STACKBOTTOM_ALIGNMENT_M1)
+ & ~STACKBOTTOM_ALIGNMENT_M1);
+ # else
+ result = (ptr_t)(((word)(&dummy))
+ & ~STACKBOTTOM_ALIGNMENT_M1);
+ # endif
+ # endif /* HEURISTIC1 */
+ # ifdef LINUX_STACKBOTTOM
+ result = GC_linux_stack_base();
+ # endif
+ # ifdef FREEBSD_STACKBOTTOM
+ result = GC_freebsd_stack_base();
+ # endif
+ # ifdef HEURISTIC2
+ # ifdef STACK_GROWS_DOWN
+ result = GC_find_limit((ptr_t)(&dummy), TRUE);
+ # ifdef HEURISTIC2_LIMIT
+ if (result > HEURISTIC2_LIMIT
+ && (ptr_t)(&dummy) < HEURISTIC2_LIMIT) {
+ result = HEURISTIC2_LIMIT;
+ }
+ # endif
+ # else
+ result = GC_find_limit((ptr_t)(&dummy), FALSE);
+ # ifdef HEURISTIC2_LIMIT
+ if (result < HEURISTIC2_LIMIT
+ && (ptr_t)(&dummy) > HEURISTIC2_LIMIT) {
+ result = HEURISTIC2_LIMIT;
+ }
+ # endif
+ # endif
+
+ # endif /* HEURISTIC2 */
+ # ifdef STACK_GROWS_DOWN
+ if (result == 0) result = (ptr_t)(signed_word)(-sizeof(ptr_t));
+ # endif
+ return(result);
+ # endif /* STACKBOTTOM */
+ }
+
+ # endif /* ! AMIGA, !OS 2, ! MS Windows, !BEOS */
+
+ /*
+ * Register static data segment(s) as roots.
+ * If more data segments are added later then they need to be registered
+ * add that point (as we do with SunOS dynamic loading),
+ * or GC_mark_roots needs to check for them (as we do with PCR).
+ * Called with allocator lock held.
+ */
+
+ # ifdef OS2
+
+ void GC_register_data_segments()
+ {
+ PTIB ptib;
+ PPIB ppib;
+ HMODULE module_handle;
+ # define PBUFSIZ 512
+ UCHAR path[PBUFSIZ];
+ FILE * myexefile;
+ struct exe_hdr hdrdos; /* MSDOS header. */
+ struct e32_exe hdr386; /* Real header for my executable */
+ struct o32_obj seg; /* Currrent segment */
+ int nsegs;
+
+
+ if (DosGetInfoBlocks(&ptib, &ppib) != NO_ERROR) {
+ GC_err_printf0("DosGetInfoBlocks failed\n");
+ ABORT("DosGetInfoBlocks failed\n");
+ }
+ module_handle = ppib -> pib_hmte;
+ if (DosQueryModuleName(module_handle, PBUFSIZ, path) != NO_ERROR) {
+ GC_err_printf0("DosQueryModuleName failed\n");
+ ABORT("DosGetInfoBlocks failed\n");
+ }
+ myexefile = fopen(path, "rb");
+ if (myexefile == 0) {
+ GC_err_puts("Couldn't open executable ");
+ GC_err_puts(path); GC_err_puts("\n");
+ ABORT("Failed to open executable\n");
+ }
+ if (fread((char *)(&hdrdos), 1, sizeof hdrdos, myexefile) < sizeof
hdrdos) {
+ GC_err_puts("Couldn't read MSDOS header from ");
+ GC_err_puts(path); GC_err_puts("\n");
+ ABORT("Couldn't read MSDOS header");
+ }
+ if (E_MAGIC(hdrdos) != EMAGIC) {
+ GC_err_puts("Executable has wrong DOS magic number: ");
+ GC_err_puts(path); GC_err_puts("\n");
+ ABORT("Bad DOS magic number");
+ }
+ if (fseek(myexefile, E_LFANEW(hdrdos), SEEK_SET) != 0) {
+ GC_err_puts("Seek to new header failed in ");
+ GC_err_puts(path); GC_err_puts("\n");
+ ABORT("Bad DOS magic number");
+ }
+ if (fread((char *)(&hdr386), 1, sizeof hdr386, myexefile) < sizeof
hdr386) {
+ GC_err_puts("Couldn't read MSDOS header from ");
+ GC_err_puts(path); GC_err_puts("\n");
+ ABORT("Couldn't read OS/2 header");
+ }
+ if (E32_MAGIC1(hdr386) != E32MAGIC1 || E32_MAGIC2(hdr386) != E32MAGIC2) {
+ GC_err_puts("Executable has wrong OS/2 magic number:");
+ GC_err_puts(path); GC_err_puts("\n");
+ ABORT("Bad OS/2 magic number");
+ }
+ if ( E32_BORDER(hdr386) != E32LEBO || E32_WORDER(hdr386) != E32LEWO) {
+ GC_err_puts("Executable %s has wrong byte order: ");
+ GC_err_puts(path); GC_err_puts("\n");
+ ABORT("Bad byte order");
+ }
+ if ( E32_CPU(hdr386) == E32CPU286) {
+ GC_err_puts("GC can't handle 80286 executables: ");
+ GC_err_puts(path); GC_err_puts("\n");
+ EXIT();
+ }
+ if (fseek(myexefile, E_LFANEW(hdrdos) + E32_OBJTAB(hdr386),
+ SEEK_SET) != 0) {
+ GC_err_puts("Seek to object table failed: ");
+ GC_err_puts(path); GC_err_puts("\n");
+ ABORT("Seek to object table failed");
+ }
+ for (nsegs = E32_OBJCNT(hdr386); nsegs > 0; nsegs--) {
+ int flags;
+ if (fread((char *)(&seg), 1, sizeof seg, myexefile) < sizeof seg) {
+ GC_err_puts("Couldn't read obj table entry from ");
+ GC_err_puts(path); GC_err_puts("\n");
+ ABORT("Couldn't read obj table entry");
+ }
+ flags = O32_FLAGS(seg);
+ if (!(flags & OBJWRITE)) continue;
+ if (!(flags & OBJREAD)) continue;
+ if (flags & OBJINVALID) {
+ GC_err_printf0("Object with invalid pages?\n");
+ continue;
+ }
+ GC_add_roots_inner(O32_BASE(seg), O32_BASE(seg)+O32_SIZE(seg), FALSE);
+ }
+ }
+
+ # else /* !OS2 */
+
+ # if defined(MSWIN32) || defined(MSWINCE)
+
+ # ifdef MSWIN32
+ /* Unfortunately, we have to handle win32s very differently from NT,
*/
+ /* Since VirtualQuery has very different semantics. In particular, */
+ /* under win32s a VirtualQuery call on an unmapped page returns an */
+ /* invalid result. Under NT, GC_register_data_segments is a noop and
*/
+ /* all real work is done by GC_register_dynamic_libraries. Under */
+ /* win32s, we cannot find the data segments associated with dll's. */
+ /* We register the main data segment here. */
+ GC_bool GC_no_win32_dlls = FALSE;
+ /* This used to be set for gcc, to avoid dealing with */
+ /* the structured exception handling issues. But we now have */
+ /* assembly code to do that right. */
+
+ void GC_init_win32()
+ {
+ /* if we're running under win32s, assume that no DLLs will be loaded */
+ DWORD v = GetVersion();
+ GC_no_win32_dlls |= ((v & 0x80000000) && (v & 0xff) <= 3);
+ }
+
+ /* Return the smallest address a such that VirtualQuery */
+ /* returns correct results for all addresses between a and start. */
+ /* Assumes VirtualQuery returns correct information for start. */
+ ptr_t GC_least_described_address(ptr_t start)
+ {
+ MEMORY_BASIC_INFORMATION buf;
+ DWORD result;
+ LPVOID limit;
+ ptr_t p;
+ LPVOID q;
+
+ limit = GC_sysinfo.lpMinimumApplicationAddress;
+ p = (ptr_t)((word)start & ~(GC_page_size - 1));
+ for (;;) {
+ q = (LPVOID)(p - GC_page_size);
+ if ((ptr_t)q > (ptr_t)p /* underflow */ || q < limit) break;
+ result = VirtualQuery(q, &buf, sizeof(buf));
+ if (result != sizeof(buf) || buf.AllocationBase == 0) break;
+ p = (ptr_t)(buf.AllocationBase);
+ }
+ return(p);
+ }
+ # endif
+
+ # ifndef REDIRECT_MALLOC
+ /* We maintain a linked list of AllocationBase values that we know */
+ /* correspond to malloc heap sections. Currently this is only called */
+ /* during a GC. But there is some hope that for long running
*/
+ /* programs we will eventually see most heap sections. */
+
+ /* In the long run, it would be more reliable to occasionally walk */
+ /* the malloc heap with HeapWalk on the default heap. But that */
+ /* apparently works only for NT-based Windows. */
+
+ /* In the long run, a better data structure would also be nice ... */
+ struct GC_malloc_heap_list {
+ void * allocation_base;
+ struct GC_malloc_heap_list *next;
+ } *GC_malloc_heap_l = 0;
+
+ /* Is p the base of one of the malloc heap sections we already know */
+ /* about? */
+ GC_bool GC_is_malloc_heap_base(ptr_t p)
+ {
+ struct GC_malloc_heap_list *q = GC_malloc_heap_l;
+
+ while (0 != q) {
+ if (q -> allocation_base == p) return TRUE;
+ q = q -> next;
+ }
+ return FALSE;
+ }
+
+ void *GC_get_allocation_base(void *p)
+ {
+ MEMORY_BASIC_INFORMATION buf;
+ DWORD result = VirtualQuery(p, &buf, sizeof(buf));
+ if (result != sizeof(buf)) {
+ ABORT("Weird VirtualQuery result");
+ }
+ return buf.AllocationBase;
+ }
+
+ size_t GC_max_root_size = 100000; /* Appr. largest root size. */
+
+ void GC_add_current_malloc_heap()
+ {
+ struct GC_malloc_heap_list *new_l =
+ malloc(sizeof(struct GC_malloc_heap_list));
+ void * candidate = GC_get_allocation_base(new_l);
+
+ if (new_l == 0) return;
+ if (GC_is_malloc_heap_base(candidate)) {
+ /* Try a little harder to find malloc heap. */
+ size_t req_size = 10000;
+ do {
+ void *p = malloc(req_size);
+ if (0 == p) { free(new_l); return; }
+ candidate = GC_get_allocation_base(p);
+ free(p);
+ req_size *= 2;
+ } while (GC_is_malloc_heap_base(candidate)
+ && req_size < GC_max_root_size/10 && req_size < 500000);
+ if (GC_is_malloc_heap_base(candidate)) {
+ free(new_l); return;
+ }
+ }
+ # ifdef CONDPRINT
+ if (GC_print_stats)
+ GC_printf1("Found new system malloc AllocationBase at 0x%lx\n",
+ candidate);
+ # endif
+ new_l -> allocation_base = candidate;
+ new_l -> next = GC_malloc_heap_l;
+ GC_malloc_heap_l = new_l;
+ }
+ # endif /* REDIRECT_MALLOC */
+
+ /* Is p the start of either the malloc heap, or of one of our */
+ /* heap sections? */
+ GC_bool GC_is_heap_base (ptr_t p)
+ {
+
+ unsigned i;
+
+ # ifndef REDIRECT_MALLOC
+ static word last_gc_no = -1;
+
+ if (last_gc_no != GC_gc_no) {
+ GC_add_current_malloc_heap();
+ last_gc_no = GC_gc_no;
+ }
+ if (GC_root_size > GC_max_root_size) GC_max_root_size = GC_root_size;
+ if (GC_is_malloc_heap_base(p)) return TRUE;
+ # endif
+ for (i = 0; i < GC_n_heap_bases; i++) {
+ if (GC_heap_bases[i] == p) return TRUE;
+ }
+ return FALSE ;
+ }
+
+ # ifdef MSWIN32
+ void GC_register_root_section(ptr_t static_root)
+ {
+ MEMORY_BASIC_INFORMATION buf;
+ DWORD result;
+ DWORD protect;
+ LPVOID p;
+ char * base;
+ char * limit, * new_limit;
+
+ if (!GC_no_win32_dlls) return;
+ p = base = limit = GC_least_described_address(static_root);
+ while (p < GC_sysinfo.lpMaximumApplicationAddress) {
+ result = VirtualQuery(p, &buf, sizeof(buf));
+ if (result != sizeof(buf) || buf.AllocationBase == 0
+ || GC_is_heap_base(buf.AllocationBase)) break;
+ new_limit = (char *)p + buf.RegionSize;
+ protect = buf.Protect;
+ if (buf.State == MEM_COMMIT
+ && is_writable(protect)) {
+ if ((char *)p == limit) {
+ limit = new_limit;
+ } else {
+ if (base != limit) GC_add_roots_inner(base, limit, FALSE);
+ base = p;
+ limit = new_limit;
+ }
+ }
+ if (p > (LPVOID)new_limit /* overflow */) break;
+ p = (LPVOID)new_limit;
+ }
+ if (base != limit) GC_add_roots_inner(base, limit, FALSE);
+ }
+ #endif
+
+ void GC_register_data_segments()
+ {
+ # ifdef MSWIN32
+ static char dummy;
+ GC_register_root_section((ptr_t)(&dummy));
+ # endif
+ }
+
+ # else /* !OS2 && !Windows */
+
+ # if (defined(SVR4) || defined(AUX) || defined(DGUX) \
+ || (defined(LINUX) && defined(SPARC))) && !defined(PCR)
+ ptr_t GC_SysVGetDataStart(max_page_size, etext_addr)
+ int max_page_size;
+ int * etext_addr;
+ {
+ word text_end = ((word)(etext_addr) + sizeof(word) - 1)
+ & ~(sizeof(word) - 1);
+ /* etext rounded to word boundary */
+ word next_page = ((text_end + (word)max_page_size - 1)
+ & ~((word)max_page_size - 1));
+ word page_offset = (text_end & ((word)max_page_size - 1));
+ VOLATILE char * result = (char *)(next_page + page_offset);
+ /* Note that this isnt equivalent to just adding */
+ /* max_page_size to &etext if &etext is at a page boundary */
+
+ GC_setup_temporary_fault_handler();
+ if (setjmp(GC_jmp_buf) == 0) {
+ /* Try writing to the address. */
+ *result = *result;
+ GC_reset_fault_handler();
+ } else {
+ GC_reset_fault_handler();
+ /* We got here via a longjmp. The address is not readable. */
+ /* This is known to happen under Solaris 2.4 + gcc, which place */
+ /* string constants in the text segment, but after etext. */
+ /* Use plan B. Note that we now know there is a gap between */
+ /* text and data segments, so plan A bought us something. */
+ result = (char *)GC_find_limit((ptr_t)(DATAEND), FALSE);
+ }
+ return((ptr_t)result);
+ }
+ # endif
+
+ # if defined(FREEBSD) && defined(I386) && !defined(PCR)
+ /* Its unclear whether this should be identical to the above, or */
+ /* whether it should apply to non-X86 architectures. */
+ /* For now we don't assume that there is always an empty page after */
+ /* etext. But in some cases there actually seems to be slightly more. */
+ /* This also deals with holes between read-only data and writable data.
*/
+ ptr_t GC_FreeBSDGetDataStart(max_page_size, etext_addr)
+ int max_page_size;
+ int * etext_addr;
+ {
+ word text_end = ((word)(etext_addr) + sizeof(word) - 1)
+ & ~(sizeof(word) - 1);
+ /* etext rounded to word boundary */
+ VOLATILE word next_page = (text_end + (word)max_page_size - 1)
+ & ~((word)max_page_size - 1);
+ VOLATILE ptr_t result = (ptr_t)text_end;
+ GC_setup_temporary_fault_handler();
+ if (setjmp(GC_jmp_buf) == 0) {
+ /* Try reading at the address. */
+ /* This should happen before there is another thread. */
+ for (; next_page < (word)(DATAEND); next_page += (word)max_page_size)
+ *(VOLATILE char *)next_page;
+ GC_reset_fault_handler();
+ } else {
+ GC_reset_fault_handler();
+ /* As above, we go to plan B */
+ result = GC_find_limit((ptr_t)(DATAEND), FALSE);
+ }
+ return(result);
+ }
+
+ # endif
+
+
+ #ifdef AMIGA
+
+ # define GC_AMIGA_DS
+ # include "AmigaOS.c"
+ # undef GC_AMIGA_DS
+
+ #else /* !OS2 && !Windows && !AMIGA */
+
+ void GC_register_data_segments()
+ {
+ # if !defined(PCR) && !defined(SRC_M3) && !defined(MACOS)
+ # if defined(REDIRECT_MALLOC) && defined(GC_SOLARIS_THREADS)
+ /* As of Solaris 2.3, the Solaris threads implementation */
+ /* allocates the data structure for the initial thread with */
+ /* sbrk at process startup. It needs to be scanned, so that */
+ /* we don't lose some malloc allocated data structures */
+ /* hanging from it. We're on thin ice here ... */
+ extern caddr_t sbrk();
+
+ GC_add_roots_inner(DATASTART, (char *)sbrk(0), FALSE);
+ # else
+ GC_add_roots_inner(DATASTART, (char *)(DATAEND), FALSE);
+ # if defined(DATASTART2)
+ GC_add_roots_inner(DATASTART2, (char *)(DATAEND2), FALSE);
+ # endif
+ # endif
+ # endif
+ # if defined(MACOS)
+ {
+ # if defined(THINK_C)
+ extern void* GC_MacGetDataStart(void);
+ /* globals begin above stack and end at a5. */
+ GC_add_roots_inner((ptr_t)GC_MacGetDataStart(),
+ (ptr_t)LMGetCurrentA5(), FALSE);
+ # else
+ # if defined(__MWERKS__)
+ # if !__POWERPC__
+ extern void* GC_MacGetDataStart(void);
+ /* MATTHEW: Function to handle Far Globals (CW Pro 3) */
+ # if __option(far_data)
+ extern void* GC_MacGetDataEnd(void);
+ # endif
+ /* globals begin above stack and end at a5. */
+ GC_add_roots_inner((ptr_t)GC_MacGetDataStart(),
+ (ptr_t)LMGetCurrentA5(), FALSE);
+ /* MATTHEW: Handle Far Globals */
+ # if __option(far_data)
+ /* Far globals follow he QD globals: */
+ GC_add_roots_inner((ptr_t)LMGetCurrentA5(),
+ (ptr_t)GC_MacGetDataEnd(), FALSE);
+ # endif
+ # else
+ extern char __data_start__[], __data_end__[];
+ GC_add_roots_inner((ptr_t)&__data_start__,
+ (ptr_t)&__data_end__, FALSE);
+ # endif /* __POWERPC__ */
+ # endif /* __MWERKS__ */
+ # endif /* !THINK_C */
+ }
+ # endif /* MACOS */
+
+ /* Dynamic libraries are added at every collection, since they may */
+ /* change.
*/
+ }
+
+ # endif /* ! AMIGA */
+ # endif /* ! MSWIN32 && ! MSWINCE*/
+ # endif /* ! OS2 */
+
+ /*
+ * Auxiliary routines for obtaining memory from OS.
+ */
+
+ # if !defined(OS2) && !defined(PCR) && !defined(AMIGA) \
+ && !defined(MSWIN32) && !defined(MSWINCE) \
+ && !defined(MACOS) && !defined(DOS4GW)
+
+ # ifdef SUNOS4
+ extern caddr_t sbrk();
+ # endif
+ # ifdef __STDC__
+ # define SBRK_ARG_T ptrdiff_t
+ # else
+ # define SBRK_ARG_T int
+ # endif
+
+
+ # ifdef RS6000
+ /* The compiler seems to generate speculative reads one past the end of
*/
+ /* an allocated object. Hence we need to make sure that the page */
+ /* following the last heap page is also mapped.
*/
+ ptr_t GC_unix_get_mem(bytes)
+ word bytes;
+ {
+ caddr_t cur_brk = (caddr_t)sbrk(0);
+ caddr_t result;
+ SBRK_ARG_T lsbs = (word)cur_brk & (GC_page_size-1);
+ static caddr_t my_brk_val = 0;
+
+ if ((SBRK_ARG_T)bytes < 0) return(0); /* too big */
+ if (lsbs != 0) {
+ if((caddr_t)(sbrk(GC_page_size - lsbs)) == (caddr_t)(-1)) return(0);
+ }
+ if (cur_brk == my_brk_val) {
+ /* Use the extra block we allocated last time. */
+ result = (ptr_t)sbrk((SBRK_ARG_T)bytes);
+ if (result == (caddr_t)(-1)) return(0);
+ result -= GC_page_size;
+ } else {
+ result = (ptr_t)sbrk(GC_page_size + (SBRK_ARG_T)bytes);
+ if (result == (caddr_t)(-1)) return(0);
+ }
+ my_brk_val = result + bytes + GC_page_size; /* Always page aligned
*/
+ return((ptr_t)result);
+ }
+
+ #else /* Not RS6000 */
+
+ #if defined(USE_MMAP)
+ /* Tested only under Linux, IRIX5 and Solaris 2 */
+
+ #ifdef USE_MMAP_FIXED
+ # define GC_MMAP_FLAGS MAP_FIXED | MAP_PRIVATE
+ /* Seems to yield better performance on Solaris 2, but can */
+ /* be unreliable if something is already mapped at the address. */
+ #else
+ # define GC_MMAP_FLAGS MAP_PRIVATE
+ #endif
+
+ #ifndef HEAP_START
+ # define HEAP_START 0
+ #endif
+
+ ptr_t GC_unix_get_mem(bytes)
+ word bytes;
+ {
+ void *result;
+ static ptr_t last_addr = HEAP_START;
+
+ # ifndef USE_MMAP_ANON
+ static GC_bool initialized = FALSE;
+ static int fd;
+
+ if (!initialized) {
+ fd = open("/dev/zero", O_RDONLY);
+ fcntl(fd, F_SETFD, FD_CLOEXEC);
+ initialized = TRUE;
+ }
+ # endif
+
+ if (bytes & (GC_page_size -1)) ABORT("Bad GET_MEM arg");
+ # ifdef USE_MMAP_ANON
+ result = mmap(last_addr, bytes, PROT_READ | PROT_WRITE | OPT_PROT_EXEC,
+ GC_MMAP_FLAGS | MAP_ANON, -1, 0/* offset */);
+ # else
+ result = mmap(last_addr, bytes, PROT_READ | PROT_WRITE | OPT_PROT_EXEC,
+ GC_MMAP_FLAGS, fd, 0/* offset */);
+ # endif
+ if (result == MAP_FAILED) return(0);
+ last_addr = (ptr_t)result + bytes + GC_page_size - 1;
+ last_addr = (ptr_t)((word)last_addr & ~(GC_page_size - 1));
+ # if !defined(LINUX)
+ if (last_addr == 0) {
+ /* Oops. We got the end of the address space. This isn't */
+ /* usable by arbitrary C code, since one-past-end pointers */
+ /* don't work, so we discard it and try again. */
+ munmap(result, (size_t)(-GC_page_size) - (size_t)result);
+ /* Leave last page mapped, so we can't repeat. */
+ return GC_unix_get_mem(bytes);
+ }
+ # else
+ GC_ASSERT(last_addr != 0);
+ # endif
+ return((ptr_t)result);
+ }
+
+ #else /* Not RS6000, not USE_MMAP */
+ ptr_t GC_unix_get_mem(bytes)
+ word bytes;
+ {
+ ptr_t result;
+ # ifdef IRIX5
+ /* Bare sbrk isn't thread safe. Play by malloc rules. */
+ /* The equivalent may be needed on other systems as well. */
+ __LOCK_MALLOC();
+ # endif
+ {
+ ptr_t cur_brk = (ptr_t)sbrk(0);
+ SBRK_ARG_T lsbs = (word)cur_brk & (GC_page_size-1);
+
+ if ((SBRK_ARG_T)bytes < 0) return(0); /* too big */
+ if (lsbs != 0) {
+ if((ptr_t)sbrk(GC_page_size - lsbs) == (ptr_t)(-1)) return(0);
+ }
+ result = (ptr_t)sbrk((SBRK_ARG_T)bytes);
+ if (result == (ptr_t)(-1)) result = 0;
+ }
+ # ifdef IRIX5
+ __UNLOCK_MALLOC();
+ # endif
+ return(result);
+ }
+
+ #endif /* Not USE_MMAP */
+ #endif /* Not RS6000 */
+
+ # endif /* UN*X */
+
+ # ifdef OS2
+
+ void * os2_alloc(size_t bytes)
+ {
+ void * result;
+
+ if (DosAllocMem(&result, bytes, PAG_EXECUTE | PAG_READ |
+ PAG_WRITE | PAG_COMMIT)
+ != NO_ERROR) {
+ return(0);
+ }
+ if (result == 0) return(os2_alloc(bytes));
+ return(result);
+ }
+
+ # endif /* OS2 */
+
+
+ # if defined(MSWIN32) || defined(MSWINCE)
+ SYSTEM_INFO GC_sysinfo;
+ # endif
+
+ # ifdef MSWIN32
+
+ # ifdef USE_GLOBAL_ALLOC
+ # define GLOBAL_ALLOC_TEST 1
+ # else
+ # define GLOBAL_ALLOC_TEST GC_no_win32_dlls
+ # endif
+
+ word GC_n_heap_bases = 0;
+
+ ptr_t GC_win32_get_mem(bytes)
+ word bytes;
+ {
+ ptr_t result;
+
+ if (GLOBAL_ALLOC_TEST) {
+ /* VirtualAlloc doesn't like PAGE_EXECUTE_READWRITE. */
+ /* There are also unconfirmed rumors of other */
+ /* problems, so we dodge the issue. */
+ result = (ptr_t) GlobalAlloc(0, bytes + HBLKSIZE);
+ result = (ptr_t)(((word)result + HBLKSIZE) & ~(HBLKSIZE-1));
+ } else {
+ /* VirtualProtect only works on regions returned by a */
+ /* single VirtualAlloc call. Thus we allocate one */
+ /* extra page, which will prevent merging of blocks */
+ /* in separate regions, and eliminate any temptation */
+ /* to call VirtualProtect on a range spanning regions. */
+ /* This wastes a small amount of memory, and risks */
+ /* increased fragmentation. But better alternatives */
+ /* would require effort. */
+ result = (ptr_t) VirtualAlloc(NULL, bytes + 1,
+ MEM_COMMIT | MEM_RESERVE,
+ PAGE_EXECUTE_READWRITE);
+ }
+ if (HBLKDISPL(result) != 0) ABORT("Bad VirtualAlloc result");
+ /* If I read the documentation correctly, this can */
+ /* only happen if HBLKSIZE > 64k or not a power of 2. */
+ if (GC_n_heap_bases >= MAX_HEAP_SECTS) ABORT("Too many heap sections");
+ GC_heap_bases[GC_n_heap_bases++] = result;
+ return(result);
+ }
+
+ void GC_win32_free_heap ()
+ {
+ if (GC_no_win32_dlls) {
+ while (GC_n_heap_bases > 0) {
+ GlobalFree (GC_heap_bases[--GC_n_heap_bases]);
+ GC_heap_bases[GC_n_heap_bases] = 0;
+ }
+ }
+ }
+ # endif
+
+ #ifdef AMIGA
+ # define GC_AMIGA_AM
+ # include "AmigaOS.c"
+ # undef GC_AMIGA_AM
+ #endif
+
+
+ # ifdef MSWINCE
+ word GC_n_heap_bases = 0;
+
+ ptr_t GC_wince_get_mem(bytes)
+ word bytes;
+ {
+ ptr_t result;
+ word i;
+
+ /* Round up allocation size to multiple of page size */
+ bytes = (bytes + GC_page_size-1) & ~(GC_page_size-1);
+
+ /* Try to find reserved, uncommitted pages */
+ for (i = 0; i < GC_n_heap_bases; i++) {
+ if (((word)(-(signed_word)GC_heap_lengths[i])
+ & (GC_sysinfo.dwAllocationGranularity-1))
+ >= bytes) {
+ result = GC_heap_bases[i] + GC_heap_lengths[i];
+ break;
+ }
+ }
+
+ if (i == GC_n_heap_bases) {
+ /* Reserve more pages */
+ word res_bytes = (bytes + GC_sysinfo.dwAllocationGranularity-1)
+ & ~(GC_sysinfo.dwAllocationGranularity-1);
+ /* If we ever support MPROTECT_VDB here, we will probably need to
*/
+ /* ensure that res_bytes is strictly > bytes, so that VirtualProtect
*/
+ /* never spans regions. It seems to be OK for a VirtualFree argument
*/
+ /* to span regions, so we should be OK for now.
*/
+ result = (ptr_t) VirtualAlloc(NULL, res_bytes,
+ MEM_RESERVE | MEM_TOP_DOWN,
+ PAGE_EXECUTE_READWRITE);
+ if (HBLKDISPL(result) != 0) ABORT("Bad VirtualAlloc result");
+ /* If I read the documentation correctly, this can */
+ /* only happen if HBLKSIZE > 64k or not a power of 2. */
+ if (GC_n_heap_bases >= MAX_HEAP_SECTS) ABORT("Too many heap sections");
+ GC_heap_bases[GC_n_heap_bases] = result;
+ GC_heap_lengths[GC_n_heap_bases] = 0;
+ GC_n_heap_bases++;
+ }
+
+ /* Commit pages */
+ result = (ptr_t) VirtualAlloc(result, bytes,
+ MEM_COMMIT,
+ PAGE_EXECUTE_READWRITE);
+ if (result != NULL) {
+ if (HBLKDISPL(result) != 0) ABORT("Bad VirtualAlloc result");
+ GC_heap_lengths[i] += bytes;
+ }
+
+ return(result);
+ }
+ # endif
+
+ #ifdef USE_MUNMAP
+
+ /* For now, this only works on Win32/WinCE and some Unix-like */
+ /* systems. If you have something else, don't define */
+ /* USE_MUNMAP. */
+ /* We assume ANSI C to support this feature. */
+
+ #if !defined(MSWIN32) && !defined(MSWINCE)
+
+ #include <unistd.h>
+ #include <sys/mman.h>
+ #include <sys/stat.h>
+ #include <sys/types.h>
+
+ #endif
+
+ /* Compute a page aligned starting address for the unmap */
+ /* operation on a block of size bytes starting at start. */
+ /* Return 0 if the block is too small to make this feasible. */
+ ptr_t GC_unmap_start(ptr_t start, word bytes)
+ {
+ ptr_t result = start;
+ /* Round start to next page boundary. */
+ result += GC_page_size - 1;
+ result = (ptr_t)((word)result & ~(GC_page_size - 1));
+ if (result + GC_page_size > start + bytes) return 0;
+ return result;
+ }
+
+ /* Compute end address for an unmap operation on the indicated */
+ /* block. */
+ ptr_t GC_unmap_end(ptr_t start, word bytes)
+ {
+ ptr_t end_addr = start + bytes;
+ end_addr = (ptr_t)((word)end_addr & ~(GC_page_size - 1));
+ return end_addr;
+ }
+
+ /* Under Win32/WinCE we commit (map) and decommit (unmap) */
+ /* memory using VirtualAlloc and VirtualFree. These functions */
+ /* work on individual allocations of virtual memory, made */
+ /* previously using VirtualAlloc with the MEM_RESERVE flag. */
+ /* The ranges we need to (de)commit may span several of these */
+ /* allocations; therefore we use VirtualQuery to check */
+ /* allocation lengths, and split up the range as necessary. */
+
+ /* We assume that GC_remap is called on exactly the same range */
+ /* as a previous call to GC_unmap. It is safe to consistently */
+ /* round the endpoints in both places. */
+ void GC_unmap(ptr_t start, word bytes)
+ {
+ ptr_t start_addr = GC_unmap_start(start, bytes);
+ ptr_t end_addr = GC_unmap_end(start, bytes);
+ word len = end_addr - start_addr;
+ if (0 == start_addr) return;
+ # if defined(MSWIN32) || defined(MSWINCE)
+ while (len != 0) {
+ MEMORY_BASIC_INFORMATION mem_info;
+ GC_word free_len;
+ if (VirtualQuery(start_addr, &mem_info, sizeof(mem_info))
+ != sizeof(mem_info))
+ ABORT("Weird VirtualQuery result");
+ free_len = (len < mem_info.RegionSize) ? len : mem_info.RegionSize;
+ if (!VirtualFree(start_addr, free_len, MEM_DECOMMIT))
+ ABORT("VirtualFree failed");
+ GC_unmapped_bytes += free_len;
+ start_addr += free_len;
+ len -= free_len;
+ }
+ # else
+ if (munmap(start_addr, len) != 0) ABORT("munmap failed");
+ GC_unmapped_bytes += len;
+ # endif
+ }
+
+
+ void GC_remap(ptr_t start, word bytes)
+ {
+ static int zero_descr = -1;
+ ptr_t start_addr = GC_unmap_start(start, bytes);
+ ptr_t end_addr = GC_unmap_end(start, bytes);
+ word len = end_addr - start_addr;
+ ptr_t result;
+
+ # if defined(MSWIN32) || defined(MSWINCE)
+ if (0 == start_addr) return;
+ while (len != 0) {
+ MEMORY_BASIC_INFORMATION mem_info;
+ GC_word alloc_len;
+ if (VirtualQuery(start_addr, &mem_info, sizeof(mem_info))
+ != sizeof(mem_info))
+ ABORT("Weird VirtualQuery result");
+ alloc_len = (len < mem_info.RegionSize) ? len : mem_info.RegionSize;
+ result = VirtualAlloc(start_addr, alloc_len,
+ MEM_COMMIT,
+ PAGE_EXECUTE_READWRITE);
+ if (result != start_addr) {
+ ABORT("VirtualAlloc remapping failed");
+ }
+ GC_unmapped_bytes -= alloc_len;
+ start_addr += alloc_len;
+ len -= alloc_len;
+ }
+ # else
+ if (-1 == zero_descr) zero_descr = open("/dev/zero", O_RDWR);
+ fcntl(zero_descr, F_SETFD, FD_CLOEXEC);
+ if (0 == start_addr) return;
+ result = mmap(start_addr, len, PROT_READ | PROT_WRITE | OPT_PROT_EXEC,
+ MAP_FIXED | MAP_PRIVATE, zero_descr, 0);
+ if (result != start_addr) {
+ ABORT("mmap remapping failed");
+ }
+ GC_unmapped_bytes -= len;
+ # endif
+ }
+
+ /* Two adjacent blocks have already been unmapped and are about to */
+ /* be merged. Unmap the whole block. This typically requires
*/
+ /* that we unmap a small section in the middle that was not previously
*/
+ /* unmapped due to alignment constraints. */
+ void GC_unmap_gap(ptr_t start1, word bytes1, ptr_t start2, word bytes2)
+ {
+ ptr_t start1_addr = GC_unmap_start(start1, bytes1);
+ ptr_t end1_addr = GC_unmap_end(start1, bytes1);
+ ptr_t start2_addr = GC_unmap_start(start2, bytes2);
+ ptr_t end2_addr = GC_unmap_end(start2, bytes2);
+ ptr_t start_addr = end1_addr;
+ ptr_t end_addr = start2_addr;
+ word len;
+ GC_ASSERT(start1 + bytes1 == start2);
+ if (0 == start1_addr) start_addr = GC_unmap_start(start1, bytes1 +
bytes2);
+ if (0 == start2_addr) end_addr = GC_unmap_end(start1, bytes1 + bytes2);
+ if (0 == start_addr) return;
+ len = end_addr - start_addr;
+ # if defined(MSWIN32) || defined(MSWINCE)
+ while (len != 0) {
+ MEMORY_BASIC_INFORMATION mem_info;
+ GC_word free_len;
+ if (VirtualQuery(start_addr, &mem_info, sizeof(mem_info))
+ != sizeof(mem_info))
+ ABORT("Weird VirtualQuery result");
+ free_len = (len < mem_info.RegionSize) ? len : mem_info.RegionSize;
+ if (!VirtualFree(start_addr, free_len, MEM_DECOMMIT))
+ ABORT("VirtualFree failed");
+ GC_unmapped_bytes += free_len;
+ start_addr += free_len;
+ len -= free_len;
+ }
+ # else
+ if (len != 0 && munmap(start_addr, len) != 0) ABORT("munmap failed");
+ GC_unmapped_bytes += len;
+ # endif
+ }
+
+ #endif /* USE_MUNMAP */
+
+ /* Routine for pushing any additional roots. In THREADS */
+ /* environment, this is also responsible for marking from */
+ /* thread stacks. */
+ #ifndef THREADS
+ void (*GC_push_other_roots)() = 0;
+ #else /* THREADS */
+
+ # ifdef PCR
+ PCR_ERes GC_push_thread_stack(PCR_Th_T *t, PCR_Any dummy)
+ {
+ struct PCR_ThCtl_TInfoRep info;
+ PCR_ERes result;
+
+ info.ti_stkLow = info.ti_stkHi = 0;
+ result = PCR_ThCtl_GetInfo(t, &info);
+ GC_push_all_stack((ptr_t)(info.ti_stkLow), (ptr_t)(info.ti_stkHi));
+ return(result);
+ }
+
+ /* Push the contents of an old object. We treat this as stack */
+ /* data only becasue that makes it robust against mark stack */
+ /* overflow. */
+ PCR_ERes GC_push_old_obj(void *p, size_t size, PCR_Any data)
+ {
+ GC_push_all_stack((ptr_t)p, (ptr_t)p + size);
+ return(PCR_ERes_okay);
+ }
+
+
+ void GC_default_push_other_roots GC_PROTO((void))
+ {
+ /* Traverse data allocated by previous memory managers. */
+ {
+ extern struct PCR_MM_ProcsRep * GC_old_allocator;
+
+ if ((*(GC_old_allocator->mmp_enumerate))(PCR_Bool_false,
+ GC_push_old_obj, 0)
+ != PCR_ERes_okay) {
+ ABORT("Old object enumeration failed");
+ }
+ }
+ /* Traverse all thread stacks. */
+ if (PCR_ERes_IsErr(
+ PCR_ThCtl_ApplyToAllOtherThreads(GC_push_thread_stack,0))
+ || PCR_ERes_IsErr(GC_push_thread_stack(PCR_Th_CurrThread(),
0))) {
+ ABORT("Thread stack marking failed\n");
+ }
+ }
+
+ # endif /* PCR */
+
+ # ifdef SRC_M3
+
+ # ifdef ALL_INTERIOR_POINTERS
+ --> misconfigured
+ # endif
+
+ void GC_push_thread_structures GC_PROTO((void))
+ {
+ /* Not our responsibibility. */
+ }
+
+ extern void ThreadF__ProcessStacks();
+
+ void GC_push_thread_stack(start, stop)
+ word start, stop;
+ {
+ GC_push_all_stack((ptr_t)start, (ptr_t)stop + sizeof(word));
+ }
+
+ /* Push routine with M3 specific calling convention. */
+ GC_m3_push_root(dummy1, p, dummy2, dummy3)
+ word *p;
+ ptr_t dummy1, dummy2;
+ int dummy3;
+ {
+ word q = *p;
+
+ GC_PUSH_ONE_STACK(q, p);
+ }
+
+ /* M3 set equivalent to RTHeap.TracedRefTypes */
+ typedef struct { int elts[1]; } RefTypeSet;
+ RefTypeSet GC_TracedRefTypes = {{0x1}};
+
+ void GC_default_push_other_roots GC_PROTO((void))
+ {
+ /* Use the M3 provided routine for finding static roots. */
+ /* This is a bit dubious, since it presumes no C roots. */
+ /* We handle the collector roots explicitly in GC_push_roots */
+ RTMain__GlobalMapProc(GC_m3_push_root, 0, GC_TracedRefTypes);
+ if (GC_words_allocd > 0) {
+ ThreadF__ProcessStacks(GC_push_thread_stack);
+ }
+ /* Otherwise this isn't absolutely necessary, and we have */
+ /* startup ordering problems. */
+ }
+
+ # endif /* SRC_M3 */
+
+ # if defined(GC_SOLARIS_THREADS) || defined(GC_PTHREADS) || \
+ defined(GC_WIN32_THREADS)
+
+ extern void GC_push_all_stacks();
+
+ void GC_default_push_other_roots GC_PROTO((void))
+ {
+ GC_push_all_stacks();
+ }
+
+ # endif /* GC_SOLARIS_THREADS || GC_PTHREADS */
+
+ void (*GC_push_other_roots) GC_PROTO((void)) = GC_default_push_other_roots;
+
+ #endif /* THREADS */
+
+ /*
+ * Routines for accessing dirty bits on virtual pages.
+ * We plan to eventually implement four strategies for doing so:
+ * DEFAULT_VDB: A simple dummy implementation that treats every page
+ * as possibly dirty. This makes incremental collection
+ * useless, but the implementation is still correct.
+ * PCR_VDB: Use PPCRs virtual dirty bit facility.
+ * PROC_VDB: Use the /proc facility for reading dirty bits. Only
+ * works under some SVR4 variants. Even then, it may be
+ * too slow to be entirely satisfactory. Requires reading
+ * dirty bits for entire address space. Implementations tend
+ * to assume that the client is a (slow) debugger.
+ * MPROTECT_VDB:Protect pages and then catch the faults to keep track of
+ * dirtied pages. The implementation (and implementability)
+ * is highly system dependent. This usually fails when system
+ * calls write to a protected page. We prevent the read system
+ * call from doing so. It is the clients responsibility to
+ * make sure that other system calls are similarly protected
+ * or write only to the stack.
+ */
+ GC_bool GC_dirty_maintained = FALSE;
+
+ # ifdef DEFAULT_VDB
+
+ /* All of the following assume the allocation lock is held, and */
+ /* signals are disabled. */
+
+ /* The client asserts that unallocated pages in the heap are never */
+ /* written. */
+
+ /* Initialize virtual dirty bit implementation. */
+ void GC_dirty_init()
+ {
+ # ifdef PRINTSTATS
+ GC_printf0("Initializing DEFAULT_VDB...\n");
+ # endif
+ GC_dirty_maintained = TRUE;
+ }
+
+ /* Retrieve system dirty bits for heap to a local buffer. */
+ /* Restore the systems notion of which pages are dirty. */
+ void GC_read_dirty()
+ {}
+
+ /* Is the HBLKSIZE sized page at h marked dirty in the local buffer? */
+ /* If the actual page size is different, this returns TRUE if any */
+ /* of the pages overlapping h are dirty. This routine may err on the */
+ /* side of labelling pages as dirty (and this implementation does). */
+ /*ARGSUSED*/
+ GC_bool GC_page_was_dirty(h)
+ struct hblk *h;
+ {
+ return(TRUE);
+ }
+
+ /*
+ * The following two routines are typically less crucial. They matter
+ * most with large dynamic libraries, or if we can't accurately identify
+ * stacks, e.g. under Solaris 2.X. Otherwise the following default
+ * versions are adequate.
+ */
+
+ /* Could any valid GC heap pointer ever have been written to this page?
*/
+ /*ARGSUSED*/
+ GC_bool GC_page_was_ever_dirty(h)
+ struct hblk *h;
+ {
+ return(TRUE);
+ }
+
+ /* Reset the n pages starting at h to "was never dirty" status. */
+ void GC_is_fresh(h, n)
+ struct hblk *h;
+ word n;
+ {
+ }
+
+ /* A call that: */
+ /* I) hints that [h, h+nblocks) is about to be written. */
+ /* II) guarantees that protection is removed. */
+ /* (I) may speed up some dirty bit implementations. */
+ /* (II) may be essential if we need to ensure that */
+ /* pointer-free system call buffers in the heap are */
+ /* not protected. */
+ /*ARGSUSED*/
+ void GC_remove_protection(h, nblocks, is_ptrfree)
+ struct hblk *h;
+ word nblocks;
+ GC_bool is_ptrfree;
+ {
+ }
+
+ # endif /* DEFAULT_VDB */
+
+
+ # ifdef MPROTECT_VDB
+
+ /*
+ * See DEFAULT_VDB for interface descriptions.
+ */
+
+ /*
+ * This implementation maintains dirty bits itself by catching write
+ * faults and keeping track of them. We assume nobody else catches
+ * SIGBUS or SIGSEGV. We assume no write faults occur in system calls.
+ * This means that clients must ensure that system calls don't write
+ * to the write-protected heap. Probably the best way to do this is to
+ * ensure that system calls write at most to POINTERFREE objects in the
+ * heap, and do even that only if we are on a platform on which those
+ * are not protected. Another alternative is to wrap system calls
+ * (see example for read below), but the current implementation holds
+ * a lock across blocking calls, making it problematic for multithreaded
+ * applications.
+ * We assume the page size is a multiple of HBLKSIZE.
+ * We prefer them to be the same. We avoid protecting POINTERFREE
+ * objects only if they are the same.
+ */
+
+ # if !defined(MSWIN32) && !defined(MSWINCE) && !defined(DARWIN)
+
+ # include <sys/mman.h>
+ # include <signal.h>
+ # include <sys/syscall.h>
+
+ # define PROTECT(addr, len) \
+ if (mprotect((caddr_t)(addr), (size_t)(len), \
+ PROT_READ | OPT_PROT_EXEC) < 0) { \
+ ABORT("mprotect failed"); \
+ }
+ # define UNPROTECT(addr, len) \
+ if (mprotect((caddr_t)(addr), (size_t)(len), \
+ PROT_WRITE | PROT_READ | OPT_PROT_EXEC ) < 0) { \
+ ABORT("un-mprotect failed"); \
+ }
+
+ # else
+
+ # ifdef DARWIN
+ /* Using vm_protect (mach syscall) over mprotect (BSD syscall) seems to
+ decrease the likelihood of some of the problems described below. */
+ #include <mach/vm_map.h>
+ extern mach_port_t GC_task_self;
+ #define PROTECT(addr,len) \
+ if(vm_protect(GC_task_self,(vm_address_t)(addr),(vm_size_t)(len), \
+ FALSE,VM_PROT_READ) != KERN_SUCCESS) { \
+ ABORT("vm_portect failed"); \
+ }
+ #define UNPROTECT(addr,len) \
+ if(vm_protect(GC_task_self,(vm_address_t)(addr),(vm_size_t)(len), \
+ FALSE,VM_PROT_READ|VM_PROT_WRITE) != KERN_SUCCESS) { \
+ ABORT("vm_portect failed"); \
+ }
+ # else
+
+ # ifndef MSWINCE
+ # include <signal.h>
+ # endif
+
+ static DWORD protect_junk;
+ # define PROTECT(addr, len) \
+ if (!VirtualProtect((addr), (len), PAGE_EXECUTE_READ, \
+ &protect_junk)) { \
+ DWORD last_error = GetLastError(); \
+ GC_printf1("Last error code: %lx\n", last_error); \
+ ABORT("VirtualProtect failed"); \
+ }
+ # define UNPROTECT(addr, len) \
+ if (!VirtualProtect((addr), (len), PAGE_EXECUTE_READWRITE, \
+ &protect_junk)) { \
+ ABORT("un-VirtualProtect failed"); \
+ }
+ # endif /* !DARWIN */
+ # endif /* MSWIN32 || MSWINCE || DARWIN */
+
+ #if defined(SUNOS4) || defined(FREEBSD)
+ typedef void (* SIG_PF)();
+ #endif /* SUNOS4 || FREEBSD */
+
+ #if defined(SUNOS5SIGS) || defined(OSF1) || defined(LINUX) \
+ || defined(HURD)
+ # ifdef __STDC__
+ typedef void (* SIG_PF)(int);
+ # else
+ typedef void (* SIG_PF)();
+ # endif
+ #endif /* SUNOS5SIGS || OSF1 || LINUX || HURD */
+
+ #if defined(MSWIN32)
+ typedef LPTOP_LEVEL_EXCEPTION_FILTER SIG_PF;
+ # undef SIG_DFL
+ # define SIG_DFL (LPTOP_LEVEL_EXCEPTION_FILTER) (-1)
+ #endif
+ #if defined(MSWINCE)
+ typedef LONG (WINAPI *SIG_PF)(struct _EXCEPTION_POINTERS *);
+ # undef SIG_DFL
+ # define SIG_DFL (SIG_PF) (-1)
+ #endif
+
+ #if defined(IRIX5) || defined(OSF1) || defined(HURD)
+ typedef void (* REAL_SIG_PF)(int, int, struct sigcontext *);
+ #endif /* IRIX5 || OSF1 || HURD */
+
+ #if defined(SUNOS5SIGS)
+ # ifdef HPUX
+ # define SIGINFO __siginfo
+ # else
+ # define SIGINFO siginfo
+ # endif
+ # ifdef __STDC__
+ typedef void (* REAL_SIG_PF)(int, struct SIGINFO *, void *);
+ # else
+ typedef void (* REAL_SIG_PF)();
+ # endif
+ #endif /* SUNOS5SIGS */
+
+ #if defined(LINUX)
+ # if __GLIBC__ > 2 || __GLIBC__ == 2 && __GLIBC_MINOR__ >= 2
+ typedef struct sigcontext s_c;
+ # else /* glibc < 2.2 */
+ # include <linux/version.h>
+ # if (LINUX_VERSION_CODE >= 0x20100) && !defined(M68K) || defined(ALPHA)
|| defined(ARM32)
+ typedef struct sigcontext s_c;
+ # else
+ typedef struct sigcontext_struct s_c;
+ # endif
+ # endif /* glibc < 2.2 */
+ # if defined(ALPHA) || defined(M68K)
+ typedef void (* REAL_SIG_PF)(int, int, s_c *);
+ # else
+ # if defined(IA64) || defined(HP_PA)
+ typedef void (* REAL_SIG_PF)(int, siginfo_t *, s_c *);
+ # else
+ typedef void (* REAL_SIG_PF)(int, s_c);
+ # endif
+ # endif
+ # ifdef ALPHA
+ /* Retrieve fault address from sigcontext structure by decoding */
+ /* instruction. */
+ char * get_fault_addr(s_c *sc) {
+ unsigned instr;
+ word faultaddr;
+
+ instr = *((unsigned *)(sc->sc_pc));
+ faultaddr = sc->sc_regs[(instr >> 16) & 0x1f];
+ faultaddr += (word) (((int)instr << 16) >> 16);
+ return (char *)faultaddr;
+ }
+ # endif /* !ALPHA */
+ # endif /* LINUX */
+
+ #ifndef DARWIN
+ SIG_PF GC_old_bus_handler;
+ SIG_PF GC_old_segv_handler; /* Also old MSWIN32 ACCESS_VIOLATION filter */
+ #endif /* !DARWIN */
+
+ #if defined(THREADS)
+ /* We need to lock around the bitmap update in the write fault handler
*/
+ /* in order to avoid the risk of losing a bit. We do this with a */
+ /* test-and-set spin lock if we know how to do that. Otherwise we */
+ /* check whether we are already in the handler and use the dumb but */
+ /* safe fallback algorithm of setting all bits in the word. */
+ /* Contention should be very rare, so we do the minimum to handle it */
+ /* correctly. */
+ #ifdef GC_TEST_AND_SET_DEFINED
+ static VOLATILE unsigned int fault_handler_lock = 0;
+ void async_set_pht_entry_from_index(VOLATILE page_hash_table db, int index)
{
+ while (GC_test_and_set(&fault_handler_lock)) {}
+ /* Could also revert to set_pht_entry_from_index_safe if initial */
+ /* GC_test_and_set fails. */
+ set_pht_entry_from_index(db, index);
+ GC_clear(&fault_handler_lock);
+ }
+ #else /* !GC_TEST_AND_SET_DEFINED */
+ /* THIS IS INCORRECT! The dirty bit vector may be temporarily wrong,
*/
+ /* just before we notice the conflict and correct it. We may end up */
+ /* looking at it while it's wrong. But this requires contention */
+ /* exactly when a GC is triggered, which seems far less likely to */
+ /* fail than the old code, which had no reported failures. Thus we */
+ /* leave it this way while we think of something better, or support */
+ /* GC_test_and_set on the remaining platforms. */
+ static VOLATILE word currently_updating = 0;
+ void async_set_pht_entry_from_index(VOLATILE page_hash_table db, int index)
{
+ unsigned int update_dummy;
+ currently_updating = (word)(&update_dummy);
+ set_pht_entry_from_index(db, index);
+ /* If we get contention in the 10 or so instruction window here, */
+ /* and we get stopped by a GC between the two updates, we lose! */
+ if (currently_updating != (word)(&update_dummy)) {
+ set_pht_entry_from_index_safe(db, index);
+ /* We claim that if two threads concurrently try to update the */
+ /* dirty bit vector, the first one to execute UPDATE_START */
+ /* will see it changed when UPDATE_END is executed. (Note that */
+ /* &update_dummy must differ in two distinct threads.) It */
+ /* will then execute set_pht_entry_from_index_safe, thus */
+ /* returning us to a safe state, though not soon enough. */
+ }
+ }
+ #endif /* !GC_TEST_AND_SET_DEFINED */
+ #else /* !THREADS */
+ # define async_set_pht_entry_from_index(db, index) \
+ set_pht_entry_from_index(db, index)
+ #endif /* !THREADS */
+
+ /*ARGSUSED*/
+ #if !defined(DARWIN)
+ # if defined (SUNOS4) || defined(FREEBSD)
+ void GC_write_fault_handler(sig, code, scp, addr)
+ int sig, code;
+ struct sigcontext *scp;
+ char * addr;
+ # ifdef SUNOS4
+ # define SIG_OK (sig == SIGSEGV || sig == SIGBUS)
+ # define CODE_OK (FC_CODE(code) == FC_PROT \
+ || (FC_CODE(code) == FC_OBJERR \
+ && FC_ERRNO(code) == FC_PROT))
+ # endif
+ # ifdef FREEBSD
+ # define SIG_OK (sig == SIGBUS)
+ # define CODE_OK (code == BUS_PAGE_FAULT)
+ # endif
+ # endif /* SUNOS4 || FREEBSD */
+
+ # if defined(IRIX5) || defined(OSF1) || defined(HURD)
+ # include <errno.h>
+ void GC_write_fault_handler(int sig, int code, struct sigcontext *scp)
+ # ifdef OSF1
+ # define SIG_OK (sig == SIGSEGV)
+ # define CODE_OK (code == 2 /* experimentally determined */)
+ # endif
+ # ifdef IRIX5
+ # define SIG_OK (sig == SIGSEGV)
+ # define CODE_OK (code == EACCES)
+ # endif
+ # ifdef HURD
+ # define SIG_OK (sig == SIGBUS || sig == SIGSEGV)
+ # define CODE_OK TRUE
+ # endif
+ # endif /* IRIX5 || OSF1 || HURD */
+
+ # if defined(LINUX)
+ # if defined(ALPHA) || defined(M68K)
+ void GC_write_fault_handler(int sig, int code, s_c * sc)
+ # else
+ # if defined(IA64) || defined(HP_PA)
+ void GC_write_fault_handler(int sig, siginfo_t * si, s_c * scp)
+ # else
+ # if defined(ARM32)
+ void GC_write_fault_handler(int sig, int a2, int a3, int a4, s_c sc)
+ # else
+ void GC_write_fault_handler(int sig, s_c sc)
+ # endif
+ # endif
+ # endif
+ # define SIG_OK (sig == SIGSEGV)
+ # define CODE_OK TRUE
+ /* Empirically c.trapno == 14, on IA32, but is that useful? */
+ /* Should probably consider alignment issues on other */
+ /* architectures. */
+ # endif /* LINUX */
+
+ # if defined(SUNOS5SIGS)
+ # ifdef __STDC__
+ void GC_write_fault_handler(int sig, struct SIGINFO *scp, void * context)
+ # else
+ void GC_write_fault_handler(sig, scp, context)
+ int sig;
+ struct SIGINFO *scp;
+ void * context;
+ # endif
+ # ifdef HPUX
+ # define SIG_OK (sig == SIGSEGV || sig == SIGBUS)
+ # define CODE_OK (scp -> si_code == SEGV_ACCERR) \
+ || (scp -> si_code == BUS_ADRERR) \
+ || (scp -> si_code == BUS_UNKNOWN) \
+ || (scp -> si_code == SEGV_UNKNOWN) \
+ || (scp -> si_code == BUS_OBJERR)
+ # else
+ # define SIG_OK (sig == SIGSEGV)
+ # define CODE_OK (scp -> si_code == SEGV_ACCERR)
+ # endif
+ # endif /* SUNOS5SIGS */
+
+ # if defined(MSWIN32) || defined(MSWINCE)
+ LONG WINAPI GC_write_fault_handler(struct _EXCEPTION_POINTERS *exc_info)
+ # define SIG_OK (exc_info -> ExceptionRecord -> ExceptionCode == \
+ STATUS_ACCESS_VIOLATION)
+ # define CODE_OK (exc_info -> ExceptionRecord -> ExceptionInformation[0] ==
1)
+ /* Write fault */
+ # endif /* MSWIN32 || MSWINCE */
+ {
+ register unsigned i;
+ # if defined(HURD)
+ char *addr = (char *) code;
+ # endif
+ # ifdef IRIX5
+ char * addr = (char *) (size_t) (scp -> sc_badvaddr);
+ # endif
+ # if defined(OSF1) && defined(ALPHA)
+ char * addr = (char *) (scp -> sc_traparg_a0);
+ # endif
+ # ifdef SUNOS5SIGS
+ char * addr = (char *) (scp -> si_addr);
+ # endif
+ # ifdef LINUX
+ # if defined(I386) || defined (X86_64)
+ char * addr = (char *) (sc.cr2);
+ # else
+ # if defined(M68K)
+ char * addr = NULL;
+
+ struct sigcontext *scp = (struct sigcontext *)(sc);
+
+ int format = (scp->sc_formatvec >> 12) & 0xf;
+ unsigned long *framedata = (unsigned long *)(scp + 1);
+ unsigned long ea;
+
+ if (format == 0xa || format == 0xb) {
+ /* 68020/030 */
+ ea = framedata[2];
+ } else if (format == 7) {
+ /* 68040 */
+ ea = framedata[3];
+ if (framedata[1] & 0x08000000) {
+ /* correct addr on misaligned access */
+ ea = (ea+4095)&(~4095);
+ }
+ } else if (format == 4) {
+ /* 68060 */
+ ea = framedata[0];
+ if (framedata[1] & 0x08000000) {
+ /* correct addr on misaligned access */
+ ea = (ea+4095)&(~4095);
+ }
+ }
+ addr = (char *)ea;
+ # else
+ # ifdef ALPHA
+ char * addr = get_fault_addr(sc);
+ # else
+ # if defined(IA64) || defined(HP_PA)
+ char * addr = si -> si_addr;
+ /* I believe this is claimed to work on all platforms for */
+ /* Linux 2.3.47 and later. Hopefully we don't have to */
+ /* worry about earlier kernels on IA64. */
+ # else
+ # if defined(POWERPC)
+ char * addr = (char *) (sc.regs->dar);
+ # else
+ # if defined(ARM32)
+ char * addr = (char *)sc.fault_address;
+ # else
+ --> architecture not supported
+ # endif
+ # endif
+ # endif
+ # endif
+ # endif
+ # endif
+ # endif
+ # if defined(MSWIN32) || defined(MSWINCE)
+ char * addr = (char *) (exc_info -> ExceptionRecord
+ -> ExceptionInformation[1]);
+ # define sig SIGSEGV
+ # endif
+
+ if (SIG_OK && CODE_OK) {
+ register struct hblk * h =
+ (struct hblk *)((word)addr & ~(GC_page_size-1));
+ GC_bool in_allocd_block;
+
+ # ifdef SUNOS5SIGS
+ /* Address is only within the correct physical page. */
+ in_allocd_block = FALSE;
+ for (i = 0; i < divHBLKSZ(GC_page_size); i++) {
+ if (HDR(h+i) != 0) {
+ in_allocd_block = TRUE;
+ }
+ }
+ # else
+ in_allocd_block = (HDR(addr) != 0);
+ # endif
+ if (!in_allocd_block) {
+ /* Heap blocks now begin and end on page boundaries */
+ SIG_PF old_handler;
+
+ if (sig == SIGSEGV) {
+ old_handler = GC_old_segv_handler;
+ } else {
+ old_handler = GC_old_bus_handler;
+ }
+ if (old_handler == SIG_DFL) {
+ # if !defined(MSWIN32) && !defined(MSWINCE)
+ GC_err_printf1("Segfault at 0x%lx\n", addr);
+ ABORT("Unexpected bus error or segmentation fault");
+ # else
+ return(EXCEPTION_CONTINUE_SEARCH);
+ # endif
+ } else {
+ # if defined (SUNOS4) || defined(FREEBSD)
+ (*old_handler) (sig, code, scp, addr);
+ return;
+ # endif
+ # if defined (SUNOS5SIGS)
+ (*(REAL_SIG_PF)old_handler) (sig, scp, context);
+ return;
+ # endif
+ # if defined (LINUX)
+ # if defined(ALPHA) || defined(M68K)
+ (*(REAL_SIG_PF)old_handler) (sig, code, sc);
+ # else
+ # if defined(IA64) || defined(HP_PA)
+ (*(REAL_SIG_PF)old_handler) (sig, si, scp);
+ # else
+ (*(REAL_SIG_PF)old_handler) (sig, sc);
+ # endif
+ # endif
+ return;
+ # endif
+ # if defined (IRIX5) || defined(OSF1) || defined(HURD)
+ (*(REAL_SIG_PF)old_handler) (sig, code, scp);
+ return;
+ # endif
+ # ifdef MSWIN32
+ return((*old_handler)(exc_info));
+ # endif
+ }
+ }
+ UNPROTECT(h, GC_page_size);
+ /* We need to make sure that no collection occurs between */
+ /* the UNPROTECT and the setting of the dirty bit. Otherwise */
+ /* a write by a third thread might go unnoticed. Reversing */
+ /* the order is just as bad, since we would end up unprotecting */
+ /* a page in a GC cycle during which it's not marked. */
+ /* Currently we do this by disabling the thread stopping */
+ /* signals while this handler is running. An alternative might */
+ /* be to record the fact that we're about to unprotect, or */
+ /* have just unprotected a page in the GC's thread structure, */
+ /* and then to have the thread stopping code set the dirty */
+ /* flag, if necessary. */
+ for (i = 0; i < divHBLKSZ(GC_page_size); i++) {
+ register int index = PHT_HASH(h+i);
+
+ async_set_pht_entry_from_index(GC_dirty_pages, index);
+ }
+ # if defined(OSF1)
+ /* These reset the signal handler each time by default. */
+ signal(SIGSEGV, (SIG_PF) GC_write_fault_handler);
+ # endif
+ /* The write may not take place before dirty bits are read. */
+ /* But then we'll fault again ... */
+ # if defined(MSWIN32) || defined(MSWINCE)
+ return(EXCEPTION_CONTINUE_EXECUTION);
+ # else
+ return;
+ # endif
+ }
+ #if defined(MSWIN32) || defined(MSWINCE)
+ return EXCEPTION_CONTINUE_SEARCH;
+ #else
+ GC_err_printf1("Segfault at 0x%lx\n", addr);
+ ABORT("Unexpected bus error or segmentation fault");
+ #endif
+ }
+ #endif /* !DARWIN */
+
+ /*
+ * We hold the allocation lock. We expect block h to be written
+ * shortly. Ensure that all pages containing any part of the n hblks
+ * starting at h are no longer protected. If is_ptrfree is false,
+ * also ensure that they will subsequently appear to be dirty.
+ */
+ void GC_remove_protection(h, nblocks, is_ptrfree)
+ struct hblk *h;
+ word nblocks;
+ GC_bool is_ptrfree;
+ {
+ struct hblk * h_trunc; /* Truncated to page boundary */
+ struct hblk * h_end; /* Page boundary following block end */
+ struct hblk * current;
+ GC_bool found_clean;
+
+ if (!GC_dirty_maintained) return;
+ h_trunc = (struct hblk *)((word)h & ~(GC_page_size-1));
+ h_end = (struct hblk *)(((word)(h + nblocks) + GC_page_size-1)
+ & ~(GC_page_size-1));
+ found_clean = FALSE;
+ for (current = h_trunc; current < h_end; ++current) {
+ int index = PHT_HASH(current);
+
+ if (!is_ptrfree || current < h || current >= h + nblocks) {
+ async_set_pht_entry_from_index(GC_dirty_pages, index);
+ }
+ }
+ UNPROTECT(h_trunc, (ptr_t)h_end - (ptr_t)h_trunc);
+ }
+
+ #if !defined(DARWIN)
+ void GC_dirty_init()
+ {
+ # if defined(SUNOS5SIGS) || defined(IRIX5) || defined(LINUX) || \
+ defined(OSF1) || defined(HURD)
+ struct sigaction act, oldact;
+ /* We should probably specify SA_SIGINFO for Linux, and handle */
+ /* the different architectures more uniformly. */
+ # if defined(IRIX5) || defined(LINUX) || defined(OSF1) || defined(HURD)
+ act.sa_flags = SA_RESTART;
+ act.sa_handler = (SIG_PF)GC_write_fault_handler;
+ # else
+ act.sa_flags = SA_RESTART | SA_SIGINFO;
+ act.sa_sigaction = GC_write_fault_handler;
+ # endif
+ (void)sigemptyset(&act.sa_mask);
+ # ifdef SIG_SUSPEND
+ /* Arrange to postpone SIG_SUSPEND while we're in a write fault
*/
+ /* handler. This effectively makes the handler atomic w.r.t. */
+ /* stopping the world for GC. */
+ (void)sigaddset(&act.sa_mask, SIG_SUSPEND);
+ # endif /* SIG_SUSPEND */
+ # endif
+ # ifdef PRINTSTATS
+ GC_printf0("Inititalizing mprotect virtual dirty bit implementation\n");
+ # endif
+ GC_dirty_maintained = TRUE;
+ if (GC_page_size % HBLKSIZE != 0) {
+ GC_err_printf0("Page size not multiple of HBLKSIZE\n");
+ ABORT("Page size not multiple of HBLKSIZE");
+ }
+ # if defined(SUNOS4) || defined(FREEBSD)
+ GC_old_bus_handler = signal(SIGBUS, GC_write_fault_handler);
+ if (GC_old_bus_handler == SIG_IGN) {
+ GC_err_printf0("Previously ignored bus error!?");
+ GC_old_bus_handler = SIG_DFL;
+ }
+ if (GC_old_bus_handler != SIG_DFL) {
+ # ifdef PRINTSTATS
+ GC_err_printf0("Replaced other SIGBUS handler\n");
+ # endif
+ }
+ # endif
+ # if defined(SUNOS4)
+ GC_old_segv_handler = signal(SIGSEGV, (SIG_PF)GC_write_fault_handler);
+ if (GC_old_segv_handler == SIG_IGN) {
+ GC_err_printf0("Previously ignored segmentation violation!?");
+ GC_old_segv_handler = SIG_DFL;
+ }
+ if (GC_old_segv_handler != SIG_DFL) {
+ # ifdef PRINTSTATS
+ GC_err_printf0("Replaced other SIGSEGV handler\n");
+ # endif
+ }
+ # endif
+ # if defined(SUNOS5SIGS) || defined(IRIX5) || defined(LINUX) \
+ || defined(OSF1) || defined(HURD)
+ /* SUNOS5SIGS includes HPUX */
+ # if defined(GC_IRIX_THREADS)
+ sigaction(SIGSEGV, 0, &oldact);
+ sigaction(SIGSEGV, &act, 0);
+ # else
+ {
+ int res = sigaction(SIGSEGV, &act, &oldact);
+ if (res != 0) ABORT("Sigaction failed");
+ }
+ # endif
+ # if defined(_sigargs) || defined(HURD) || !defined(SA_SIGINFO)
+ /* This is Irix 5.x, not 6.x. Irix 5.x does not have */
+ /* sa_sigaction. */
+ GC_old_segv_handler = oldact.sa_handler;
+ # else /* Irix 6.x or SUNOS5SIGS or LINUX */
+ if (oldact.sa_flags & SA_SIGINFO) {
+ GC_old_segv_handler = (SIG_PF)(oldact.sa_sigaction);
+ } else {
+ GC_old_segv_handler = oldact.sa_handler;
+ }
+ # endif
+ if (GC_old_segv_handler == SIG_IGN) {
+ GC_err_printf0("Previously ignored segmentation violation!?");
+ GC_old_segv_handler = SIG_DFL;
+ }
+ if (GC_old_segv_handler != SIG_DFL) {
+ # ifdef PRINTSTATS
+ GC_err_printf0("Replaced other SIGSEGV handler\n");
+ # endif
+ }
+ # endif
+ # if defined(HPUX) || defined(LINUX) || defined(HURD)
+ sigaction(SIGBUS, &act, &oldact);
+ GC_old_bus_handler = oldact.sa_handler;
+ if (GC_old_bus_handler == SIG_IGN) {
+ GC_err_printf0("Previously ignored bus error!?");
+ GC_old_bus_handler = SIG_DFL;
+ }
+ if (GC_old_bus_handler != SIG_DFL) {
+ # ifdef PRINTSTATS
+ GC_err_printf0("Replaced other SIGBUS handler\n");
+ # endif
+ }
+ # endif /* HPUX || LINUX || HURD */
+ # if defined(MSWIN32)
+ GC_old_segv_handler =
SetUnhandledExceptionFilter(GC_write_fault_handler);
+ if (GC_old_segv_handler != NULL) {
+ # ifdef PRINTSTATS
+ GC_err_printf0("Replaced other UnhandledExceptionFilter\n");
+ # endif
+ } else {
+ GC_old_segv_handler = SIG_DFL;
+ }
+ # endif
+ }
+ #endif /* !DARWIN */
+
+ int GC_incremental_protection_needs()
+ {
+ if (GC_page_size == HBLKSIZE) {
+ return GC_PROTECTS_POINTER_HEAP;
+ } else {
+ return GC_PROTECTS_POINTER_HEAP | GC_PROTECTS_PTRFREE_HEAP;
+ }
+ }
+
+ #define HAVE_INCREMENTAL_PROTECTION_NEEDS
+
+ #define IS_PTRFREE(hhdr) ((hhdr)->hb_descr == 0)
+
+ #define PAGE_ALIGNED(x) !((word)(x) & (GC_page_size - 1))
+ void GC_protect_heap()
+ {
+ ptr_t start;
+ word len;
+ struct hblk * current;
+ struct hblk * current_start; /* Start of block to be protected. */
+ struct hblk * limit;
+ unsigned i;
+ GC_bool protect_all =
+ (0 != (GC_incremental_protection_needs() & GC_PROTECTS_PTRFREE_HEAP));
+ for (i = 0; i < GC_n_heap_sects; i++) {
+ start = GC_heap_sects[i].hs_start;
+ len = GC_heap_sects[i].hs_bytes;
+ if (protect_all) {
+ PROTECT(start, len);
+ } else {
+ GC_ASSERT(PAGE_ALIGNED(len))
+ GC_ASSERT(PAGE_ALIGNED(start))
+ current_start = current = (struct hblk *)start;
+ limit = (struct hblk *)(start + len);
+ while (current < limit) {
+ hdr * hhdr;
+ word nhblks;
+ GC_bool is_ptrfree;
+
+ GC_ASSERT(PAGE_ALIGNED(current));
+ GET_HDR(current, hhdr);
+ if (IS_FORWARDING_ADDR_OR_NIL(hhdr)) {
+ /* This can happen only if we're at the beginning of a */
+ /* heap segment, and a block spans heap segments. */
+ /* We will handle that block as part of the preceding */
+ /* segment. */
+ GC_ASSERT(current_start == current);
+ current_start = ++current;
+ continue;
+ }
+ if (HBLK_IS_FREE(hhdr)) {
+ GC_ASSERT(PAGE_ALIGNED(hhdr -> hb_sz));
+ nhblks = divHBLKSZ(hhdr -> hb_sz);
+ is_ptrfree = TRUE; /* dirty on alloc */
+ } else {
+ nhblks = OBJ_SZ_TO_BLOCKS(hhdr -> hb_sz);
+ is_ptrfree = IS_PTRFREE(hhdr);
+ }
+ if (is_ptrfree) {
+ if (current_start < current) {
+ PROTECT(current_start, (ptr_t)current - (ptr_t)current_start);
+ }
+ current_start = (current += nhblks);
+ } else {
+ current += nhblks;
+ }
+ }
+ if (current_start < current) {
+ PROTECT(current_start, (ptr_t)current - (ptr_t)current_start);
+ }
+ }
+ }
+ }
+
+ /* We assume that either the world is stopped or its OK to lose dirty */
+ /* bits while this is happenning (as in GC_enable_incremental).
*/
+ void GC_read_dirty()
+ {
+ BCOPY((word *)GC_dirty_pages, GC_grungy_pages,
+ (sizeof GC_dirty_pages));
+ BZERO((word *)GC_dirty_pages, (sizeof GC_dirty_pages));
+ GC_protect_heap();
+ }
+
+ GC_bool GC_page_was_dirty(h)
+ struct hblk * h;
+ {
+ register word index = PHT_HASH(h);
+
+ return(HDR(h) == 0 || get_pht_entry_from_index(GC_grungy_pages, index));
+ }
+
+ /*
+ * Acquiring the allocation lock here is dangerous, since this
+ * can be called from within GC_call_with_alloc_lock, and the cord
+ * package does so. On systems that allow nested lock acquisition, this
+ * happens to work.
+ * On other systems, SET_LOCK_HOLDER and friends must be suitably defined.
+ */
+
+ static GC_bool syscall_acquired_lock = FALSE; /* Protected by GC lock. */
+
+ void GC_begin_syscall()
+ {
+ if (!I_HOLD_LOCK()) {
+ LOCK();
+ syscall_acquired_lock = TRUE;
+ }
+ }
+
+ void GC_end_syscall()
+ {
+ if (syscall_acquired_lock) {
+ syscall_acquired_lock = FALSE;
+ UNLOCK();
+ }
+ }
+
+ void GC_unprotect_range(addr, len)
+ ptr_t addr;
+ word len;
+ {
+ struct hblk * start_block;
+ struct hblk * end_block;
+ register struct hblk *h;
+ ptr_t obj_start;
+
+ if (!GC_dirty_maintained) return;
+ obj_start = GC_base(addr);
+ if (obj_start == 0) return;
+ if (GC_base(addr + len - 1) != obj_start) {
+ ABORT("GC_unprotect_range(range bigger than object)");
+ }
+ start_block = (struct hblk *)((word)addr & ~(GC_page_size - 1));
+ end_block = (struct hblk *)((word)(addr + len - 1) & ~(GC_page_size - 1));
+ end_block += GC_page_size/HBLKSIZE - 1;
+ for (h = start_block; h <= end_block; h++) {
+ register word index = PHT_HASH(h);
+
+ async_set_pht_entry_from_index(GC_dirty_pages, index);
+ }
+ UNPROTECT(start_block,
+ ((ptr_t)end_block - (ptr_t)start_block) + HBLKSIZE);
+ }
+
+ #if 0
+
+ /* We no longer wrap read by default, since that was causing too many */
+ /* problems. It is preferred that the client instead avoids writing */
+ /* to the write-protected heap with a system call. */
+ /* This still serves as sample code if you do want to wrap system calls.*/
+
+ #if !defined(MSWIN32) && !defined(MSWINCE) && !defined(GC_USE_LD_WRAP)
+ /* Replacement for UNIX system call. */
+ /* Other calls that write to the heap should be handled similarly. */
+ /* Note that this doesn't work well for blocking reads: It will hold */
+ /* the allocation lock for the entire duration of the call. Multithreaded */
+ /* clients should really ensure that it won't block, either by setting
*/
+ /* the descriptor nonblocking, or by calling select or poll first, to */
+ /* make sure that input is available. */
+ /* Another, preferred alternative is to ensure that system calls never
*/
+ /* write to the protected heap (see above). */
+ # if defined(__STDC__) && !defined(SUNOS4)
+ # include <unistd.h>
+ # include <sys/uio.h>
+ ssize_t read(int fd, void *buf, size_t nbyte)
+ # else
+ # ifndef LINT
+ int read(fd, buf, nbyte)
+ # else
+ int GC_read(fd, buf, nbyte)
+ # endif
+ int fd;
+ char *buf;
+ int nbyte;
+ # endif
+ {
+ int result;
+
+ GC_begin_syscall();
+ GC_unprotect_range(buf, (word)nbyte);
+ # if defined(IRIX5) || defined(GC_LINUX_THREADS)
+ /* Indirect system call may not always be easily available. */
+ /* We could call _read, but that would interfere with the */
+ /* libpthread interception of read. */
+ /* On Linux, we have to be careful with the linuxthreads */
+ /* read interception. */
+ {
+ struct iovec iov;
+
+ iov.iov_base = buf;
+ iov.iov_len = nbyte;
+ result = readv(fd, &iov, 1);
+ }
+ # else
+ # if defined(HURD)
+ result = __read(fd, buf, nbyte);
+ # else
+ /* The two zero args at the end of this list are because one
+ IA-64 syscall() implementation actually requires six args
+ to be passed, even though they aren't always used. */
+ result = syscall(SYS_read, fd, buf, nbyte, 0, 0);
+ # endif /* !HURD */
+ # endif
+ GC_end_syscall();
+ return(result);
+ }
+ #endif /* !MSWIN32 && !MSWINCE && !GC_LINUX_THREADS */
+
+ #if defined(GC_USE_LD_WRAP) && !defined(THREADS)
+ /* We use the GNU ld call wrapping facility. */
+ /* This requires that the linker be invoked with "--wrap read". */
+ /* This can be done by passing -Wl,"--wrap read" to gcc. */
+ /* I'm not sure that this actually wraps whatever version of read */
+ /* is called by stdio. That code also mentions __read. */
+ # include <unistd.h>
+ ssize_t __wrap_read(int fd, void *buf, size_t nbyte)
+ {
+ int result;
+
+ GC_begin_syscall();
+ GC_unprotect_range(buf, (word)nbyte);
+ result = __real_read(fd, buf, nbyte);
+ GC_end_syscall();
+ return(result);
+ }
+
+ /* We should probably also do this for __read, or whatever stdio */
+ /* actually calls.
*/
+ #endif
+
+ #endif /* 0 */
+
+ /*ARGSUSED*/
+ GC_bool GC_page_was_ever_dirty(h)
+ struct hblk *h;
+ {
+ return(TRUE);
+ }
+
+ /* Reset the n pages starting at h to "was never dirty" status. */
+ /*ARGSUSED*/
+ void GC_is_fresh(h, n)
+ struct hblk *h;
+ word n;
+ {
+ }
+
+ # endif /* MPROTECT_VDB */
+
+ # ifdef PROC_VDB
+
+ /*
+ * See DEFAULT_VDB for interface descriptions.
+ */
+
+ /*
+ * This implementaion assumes a Solaris 2.X like /proc pseudo-file-system
+ * from which we can read page modified bits. This facility is far from
+ * optimal (e.g. we would like to get the info for only some of the
+ * address space), but it avoids intercepting system calls.
+ */
+
+ #include <errno.h>
+ #include <sys/types.h>
+ #include <sys/signal.h>
+ #include <sys/fault.h>
+ #include <sys/syscall.h>
+ #include <sys/procfs.h>
+ #include <sys/stat.h>
+
+ #define INITIAL_BUF_SZ 4096
+ word GC_proc_buf_size = INITIAL_BUF_SZ;
+ char *GC_proc_buf;
+
+ #ifdef GC_SOLARIS_THREADS
+ /* We don't have exact sp values for threads. So we count on */
+ /* occasionally declaring stack pages to be fresh. Thus we */
+ /* need a real implementation of GC_is_fresh. We can't clear */
+ /* entries in GC_written_pages, since that would declare all */
+ /* pages with the given hash address to be fresh. */
+ # define MAX_FRESH_PAGES 8*1024 /* Must be power of 2 */
+ struct hblk ** GC_fresh_pages; /* A direct mapped cache. */
+ /* Collisions are dropped. */
+
+ # define FRESH_PAGE_SLOT(h) (divHBLKSZ((word)(h)) & (MAX_FRESH_PAGES-1))
+ # define ADD_FRESH_PAGE(h) \
+ GC_fresh_pages[FRESH_PAGE_SLOT(h)] = (h)
+ # define PAGE_IS_FRESH(h) \
+ (GC_fresh_pages[FRESH_PAGE_SLOT(h)] == (h) && (h) != 0)
+ #endif
+
+ /* Add all pages in pht2 to pht1 */
+ void GC_or_pages(pht1, pht2)
+ page_hash_table pht1, pht2;
+ {
+ register int i;
+
+ for (i = 0; i < PHT_SIZE; i++) pht1[i] |= pht2[i];
+ }
+
+ int GC_proc_fd;
+
+ void GC_dirty_init()
+ {
+ int fd;
+ char buf[30];
+
+ GC_dirty_maintained = TRUE;
+ if (GC_words_allocd != 0 || GC_words_allocd_before_gc != 0) {
+ register int i;
+
+ for (i = 0; i < PHT_SIZE; i++) GC_written_pages[i] = (word)(-1);
+ # ifdef PRINTSTATS
+ GC_printf1("Allocated words:%lu:all pages may have been written\n",
+ (unsigned long)
+ (GC_words_allocd + GC_words_allocd_before_gc));
+ # endif
+ }
+ sprintf(buf, "/proc/%d", getpid());
+ fd = open(buf, O_RDONLY);
+ if (fd < 0) {
+ ABORT("/proc open failed");
+ }
+ GC_proc_fd = syscall(SYS_ioctl, fd, PIOCOPENPD, 0);
+ close(fd);
+ syscall(SYS_fcntl, GC_proc_fd, F_SETFD, FD_CLOEXEC);
+ if (GC_proc_fd < 0) {
+ ABORT("/proc ioctl failed");
+ }
+ GC_proc_buf = GC_scratch_alloc(GC_proc_buf_size);
+ # ifdef GC_SOLARIS_THREADS
+ GC_fresh_pages = (struct hblk **)
+ GC_scratch_alloc(MAX_FRESH_PAGES * sizeof (struct hblk *));
+ if (GC_fresh_pages == 0) {
+ GC_err_printf0("No space for fresh pages\n");
+ EXIT();
+ }
+ BZERO(GC_fresh_pages, MAX_FRESH_PAGES * sizeof (struct hblk *));
+ # endif
+ }
+
+ /* Ignore write hints. They don't help us here. */
+ /*ARGSUSED*/
+ void GC_remove_protection(h, nblocks, is_ptrfree)
+ struct hblk *h;
+ word nblocks;
+ GC_bool is_ptrfree;
+ {
+ }
+
+ #ifdef GC_SOLARIS_THREADS
+ # define READ(fd,buf,nbytes) syscall(SYS_read, fd, buf, nbytes)
+ #else
+ # define READ(fd,buf,nbytes) read(fd, buf, nbytes)
+ #endif
+
+ void GC_read_dirty()
+ {
+ unsigned long ps, np;
+ int nmaps;
+ ptr_t vaddr;
+ struct prasmap * map;
+ char * bufp;
+ ptr_t current_addr, limit;
+ int i;
+ int dummy;
+
+ BZERO(GC_grungy_pages, (sizeof GC_grungy_pages));
+
+ bufp = GC_proc_buf;
+ if (READ(GC_proc_fd, bufp, GC_proc_buf_size) <= 0) {
+ # ifdef PRINTSTATS
+ GC_printf1("/proc read failed: GC_proc_buf_size = %lu\n",
+ GC_proc_buf_size);
+ # endif
+ {
+ /* Retry with larger buffer. */
+ word new_size = 2 * GC_proc_buf_size;
+ char * new_buf = GC_scratch_alloc(new_size);
+
+ if (new_buf != 0) {
+ GC_proc_buf = bufp = new_buf;
+ GC_proc_buf_size = new_size;
+ }
+ if (syscall(SYS_read, GC_proc_fd, bufp, GC_proc_buf_size) <= 0) {
+ WARN("Insufficient space for /proc read\n", 0);
+ /* Punt: */
+ memset(GC_grungy_pages, 0xff, sizeof (page_hash_table));
+ memset(GC_written_pages, 0xff, sizeof(page_hash_table));
+ # ifdef GC_SOLARIS_THREADS
+ BZERO(GC_fresh_pages,
+ MAX_FRESH_PAGES * sizeof (struct hblk *));
+ # endif
+ return;
+ }
+ }
+ }
+ /* Copy dirty bits into GC_grungy_pages */
+ nmaps = ((struct prpageheader *)bufp) -> pr_nmap;
+ /* printf( "nmaps = %d, PG_REFERENCED = %d, PG_MODIFIED = %d\n",
+ nmaps, PG_REFERENCED, PG_MODIFIED); */
+ bufp = bufp + sizeof(struct prpageheader);
+ for (i = 0; i < nmaps; i++) {
+ map = (struct prasmap *)bufp;
+ vaddr = (ptr_t)(map -> pr_vaddr);
+ ps = map -> pr_pagesize;
+ np = map -> pr_npage;
+ /* printf("vaddr = 0x%X, ps = 0x%X, np = 0x%X\n", vaddr, ps, np); */
+ limit = vaddr + ps * np;
+ bufp += sizeof (struct prasmap);
+ for (current_addr = vaddr;
+ current_addr < limit; current_addr += ps){
+ if ((*bufp++) & PG_MODIFIED) {
+ register struct hblk * h = (struct hblk *) current_addr;
+
+ while ((ptr_t)h < current_addr + ps) {
+ register word index = PHT_HASH(h);
+
+ set_pht_entry_from_index(GC_grungy_pages, index);
+ # ifdef GC_SOLARIS_THREADS
+ {
+ register int slot = FRESH_PAGE_SLOT(h);
+
+ if (GC_fresh_pages[slot] == h) {
+ GC_fresh_pages[slot] = 0;
+ }
+ }
+ # endif
+ h++;
+ }
+ }
+ }
+ bufp += sizeof(long) - 1;
+ bufp = (char *)((unsigned long)bufp & ~(sizeof(long)-1));
+ }
+ /* Update GC_written_pages. */
+ GC_or_pages(GC_written_pages, GC_grungy_pages);
+ # ifdef GC_SOLARIS_THREADS
+ /* Make sure that old stacks are considered completely clean */
+ /* unless written again.
*/
+ GC_old_stacks_are_fresh();
+ # endif
+ }
+
+ #undef READ
+
+ GC_bool GC_page_was_dirty(h)
+ struct hblk *h;
+ {
+ register word index = PHT_HASH(h);
+ register GC_bool result;
+
+ result = get_pht_entry_from_index(GC_grungy_pages, index);
+ # ifdef GC_SOLARIS_THREADS
+ if (result && PAGE_IS_FRESH(h)) result = FALSE;
+ /* This happens only if page was declared fresh since */
+ /* the read_dirty call, e.g. because it's in an unused */
+ /* thread stack. It's OK to treat it as clean, in */
+ /* that case. And it's consistent with */
+ /* GC_page_was_ever_dirty. */
+ # endif
+ return(result);
+ }
+
+ GC_bool GC_page_was_ever_dirty(h)
+ struct hblk *h;
+ {
+ register word index = PHT_HASH(h);
+ register GC_bool result;
+
+ result = get_pht_entry_from_index(GC_written_pages, index);
+ # ifdef GC_SOLARIS_THREADS
+ if (result && PAGE_IS_FRESH(h)) result = FALSE;
+ # endif
+ return(result);
+ }
+
+ /* Caller holds allocation lock. */
+ void GC_is_fresh(h, n)
+ struct hblk *h;
+ word n;
+ {
+
+ register word index;
+
+ # ifdef GC_SOLARIS_THREADS
+ register word i;
+
+ if (GC_fresh_pages != 0) {
+ for (i = 0; i < n; i++) {
+ ADD_FRESH_PAGE(h + i);
+ }
+ }
+ # endif
+ }
+
+ # endif /* PROC_VDB */
+
+
+ # ifdef PCR_VDB
+
+ # include "vd/PCR_VD.h"
+
+ # define NPAGES (32*1024) /* 128 MB */
+
+ PCR_VD_DB GC_grungy_bits[NPAGES];
+
+ ptr_t GC_vd_base; /* Address corresponding to GC_grungy_bits[0] */
+ /* HBLKSIZE aligned. */
+
+ void GC_dirty_init()
+ {
+ GC_dirty_maintained = TRUE;
+ /* For the time being, we assume the heap generally grows up */
+ GC_vd_base = GC_heap_sects[0].hs_start;
+ if (GC_vd_base == 0) {
+ ABORT("Bad initial heap segment");
+ }
+ if (PCR_VD_Start(HBLKSIZE, GC_vd_base, NPAGES*HBLKSIZE)
+ != PCR_ERes_okay) {
+ ABORT("dirty bit initialization failed");
+ }
+ }
+
+ void GC_read_dirty()
+ {
+ /* lazily enable dirty bits on newly added heap sects */
+ {
+ static int onhs = 0;
+ int nhs = GC_n_heap_sects;
+ for( ; onhs < nhs; onhs++ ) {
+ PCR_VD_WriteProtectEnable(
+ GC_heap_sects[onhs].hs_start,
+ GC_heap_sects[onhs].hs_bytes );
+ }
+ }
+
+
+ if (PCR_VD_Clear(GC_vd_base, NPAGES*HBLKSIZE, GC_grungy_bits)
+ != PCR_ERes_okay) {
+ ABORT("dirty bit read failed");
+ }
+ }
+
+ GC_bool GC_page_was_dirty(h)
+ struct hblk *h;
+ {
+ if((ptr_t)h < GC_vd_base || (ptr_t)h >= GC_vd_base + NPAGES*HBLKSIZE) {
+ return(TRUE);
+ }
+ return(GC_grungy_bits[h - (struct hblk *)GC_vd_base] &
PCR_VD_DB_dirtyBit);
+ }
+
+ /*ARGSUSED*/
+ void GC_remove_protection(h, nblocks, is_ptrfree)
+ struct hblk *h;
+ word nblocks;
+ GC_bool is_ptrfree;
+ {
+ PCR_VD_WriteProtectDisable(h, nblocks*HBLKSIZE);
+ PCR_VD_WriteProtectEnable(h, nblocks*HBLKSIZE);
+ }
+
+ # endif /* PCR_VDB */
+
+ #if defined(MPROTECT_VDB) && defined(DARWIN)
+ /* The following sources were used as a *reference* for this exception
handling
+ code:
+ 1. Apple's mach/xnu documentation
+ 2. Timothy J. Wood's "Mach Exception Handlers 101" post to the
+ omnigroup's macosx-dev list.
+ www.omnigroup.com/mailman/archive/macosx-dev/2000-June/002030.html
+ 3. macosx-nat.c from Apple's GDB source code.
+ */
+
+ /* There seem to be numerous problems with darwin's mach exception handling.
+ I'm pretty sure they are not problems in my code. Search for
+ BROKEN_EXCEPTION_HANDLING for more information. */
+ #define BROKEN_EXCEPTION_HANDLING
+
+ #include <mach/mach.h>
+ #include <mach/mach_error.h>
+ #include <mach/thread_status.h>
+ #include <mach/exception.h>
+ #include <mach/task.h>
+ #include <pthread.h>
+
+ /* These are not defined in any header, although they are documented */
+ extern boolean_t exc_server(mach_msg_header_t *,mach_msg_header_t *);
+ extern kern_return_t exception_raise(
+ mach_port_t,mach_port_t,mach_port_t,
+ exception_type_t,exception_data_t,mach_msg_type_number_t);
+ extern kern_return_t exception_raise_state(
+ mach_port_t,mach_port_t,mach_port_t,
+ exception_type_t,exception_data_t,mach_msg_type_number_t,
+ thread_state_flavor_t*,thread_state_t,mach_msg_type_number_t,
+ thread_state_t,mach_msg_type_number_t*);
+ extern kern_return_t exception_raise_state_identity(
+ mach_port_t,mach_port_t,mach_port_t,
+ exception_type_t,exception_data_t,mach_msg_type_number_t,
+ thread_state_flavor_t*,thread_state_t,mach_msg_type_number_t,
+ thread_state_t,mach_msg_type_number_t*);
+
+
+ #define MAX_EXCEPTION_PORTS 16
+
+ static mach_port_t GC_task_self;
+
+ static struct {
+ mach_msg_type_number_t count;
+ exception_mask_t masks[MAX_EXCEPTION_PORTS];
+ exception_handler_t ports[MAX_EXCEPTION_PORTS];
+ exception_behavior_t behaviors[MAX_EXCEPTION_PORTS];
+ thread_state_flavor_t flavors[MAX_EXCEPTION_PORTS];
+ } GC_old_exc_ports;
+
+ static struct {
+ mach_port_t exception;
+ #if defined(THREADS)
+ mach_port_t reply;
+ #endif
+ } GC_ports;
+
+ typedef struct {
+ mach_msg_header_t head;
+ } GC_msg_t;
+
+ typedef enum {
+ GC_MP_NORMAL, GC_MP_DISCARDING, GC_MP_STOPPED
+ } GC_mprotect_state_t;
+
+ /* FIXME: 1 and 2 seem to be safe to use in the msgh_id field,
+ but it isn't documented. Use the source and see if they
+ should be ok. */
+ #define ID_STOP 1
+ #define ID_RESUME 2
+
+ /* These values are only used on the reply port */
+ #define ID_ACK 3
+
+ #if defined(THREADS)
+
+ GC_mprotect_state_t GC_mprotect_state;
+
+ /* The following should ONLY be called when the world is stopped */
+ static void GC_mprotect_thread_notify(mach_msg_id_t id) {
+ struct {
+ GC_msg_t msg;
+ mach_msg_trailer_t trailer;
+ } buf;
+ mach_msg_return_t r;
+ /* remote, local */
+ buf.msg.head.msgh_bits =
+ MACH_MSGH_BITS(MACH_MSG_TYPE_MAKE_SEND,0);
+ buf.msg.head.msgh_size = sizeof(buf.msg);
+ buf.msg.head.msgh_remote_port = GC_ports.exception;
+ buf.msg.head.msgh_local_port = MACH_PORT_NULL;
+ buf.msg.head.msgh_id = id;
+
+ r = mach_msg(
+ &buf.msg.head,
+ MACH_SEND_MSG|MACH_RCV_MSG|MACH_RCV_LARGE,
+ sizeof(buf.msg),
+ sizeof(buf),
+ GC_ports.reply,
+ MACH_MSG_TIMEOUT_NONE,
+ MACH_PORT_NULL);
+ if(r != MACH_MSG_SUCCESS)
+ ABORT("mach_msg failed in GC_mprotect_thread_notify");
+ if(buf.msg.head.msgh_id != ID_ACK)
+ ABORT("invalid ack in GC_mprotect_thread_notify");
+ }
+
+ /* Should only be called by the mprotect thread */
+ static void GC_mprotect_thread_reply() {
+ GC_msg_t msg;
+ mach_msg_return_t r;
+ /* remote, local */
+ msg.head.msgh_bits =
+ MACH_MSGH_BITS(MACH_MSG_TYPE_MAKE_SEND,0);
+ msg.head.msgh_size = sizeof(msg);
+ msg.head.msgh_remote_port = GC_ports.reply;
+ msg.head.msgh_local_port = MACH_PORT_NULL;
+ msg.head.msgh_id = ID_ACK;
+
+ r = mach_msg(
+ &msg.head,
+ MACH_SEND_MSG,
+ sizeof(msg),
+ 0,
+ MACH_PORT_NULL,
+ MACH_MSG_TIMEOUT_NONE,
+ MACH_PORT_NULL);
+ if(r != MACH_MSG_SUCCESS)
+ ABORT("mach_msg failed in GC_mprotect_thread_reply");
+ }
+
+ void GC_mprotect_stop() {
+ GC_mprotect_thread_notify(ID_STOP);
+ }
+ void GC_mprotect_resume() {
+ GC_mprotect_thread_notify(ID_RESUME);
+ }
+
+ #else /* !THREADS */
+ /* The compiler should optimize away any GC_mprotect_state computations */
+ #define GC_mprotect_state GC_MP_NORMAL
+ #endif
+
+ static void *GC_mprotect_thread(void *arg) {
+ mach_msg_return_t r;
+ /* These two structures contain some private kernel data. We don't need to
+ access any of it so we don't bother defining a proper struct. The
+ correct definitions are in the xnu source code. */
+ struct {
+ mach_msg_header_t head;
+ char data[256];
+ } reply;
+ struct {
+ mach_msg_header_t head;
+ mach_msg_body_t msgh_body;
+ char data[1024];
+ } msg;
+
+ mach_msg_id_t id;
+
+ for(;;) {
+ r = mach_msg(
+ &msg.head,
+ MACH_RCV_MSG|MACH_RCV_LARGE|
+ (GC_mprotect_state == GC_MP_DISCARDING ? MACH_RCV_TIMEOUT :
0),
+ 0,
+ sizeof(msg),
+ GC_ports.exception,
+ GC_mprotect_state == GC_MP_DISCARDING ? 0 : MACH_MSG_TIMEOUT_NONE,
+ MACH_PORT_NULL);
+
+ id = r == MACH_MSG_SUCCESS ? msg.head.msgh_id : -1;
+
+ #if defined(THREADS)
+ if(GC_mprotect_state == GC_MP_DISCARDING) {
+ if(r == MACH_RCV_TIMED_OUT) {
+ GC_mprotect_state = GC_MP_STOPPED;
+ GC_mprotect_thread_reply();
+ continue;
+ }
+ if(r == MACH_MSG_SUCCESS && (id == ID_STOP || id == ID_RESUME))
+ ABORT("out of order mprotect thread request");
+ }
+ #endif
+
+ if(r != MACH_MSG_SUCCESS) {
+ GC_err_printf2("mach_msg failed with %d %s\n",
+ (int)r,mach_error_string(r));
+ ABORT("mach_msg failed");
+ }
+
+ switch(id) {
+ #if defined(THREADS)
+ case ID_STOP:
+ if(GC_mprotect_state != GC_MP_NORMAL)
+ ABORT("Called mprotect_stop when state wasn't normal");
+ GC_mprotect_state = GC_MP_DISCARDING;
+ break;
+ case ID_RESUME:
+ if(GC_mprotect_state != GC_MP_STOPPED)
+ ABORT("Called mprotect_resume when state wasn't stopped");
+ GC_mprotect_state = GC_MP_NORMAL;
+ GC_mprotect_thread_reply();
+ break;
+ #endif /* THREADS */
+ default:
+ /* Handle the message (calls catch_exception_raise) */
+ if(!exc_server(&msg.head,&reply.head))
+ ABORT("exc_server failed");
+ /* Send the reply */
+ r = mach_msg(
+ &reply.head,
+ MACH_SEND_MSG,
+ reply.head.msgh_size,
+ 0,
+ MACH_PORT_NULL,
+ MACH_MSG_TIMEOUT_NONE,
+ MACH_PORT_NULL);
+ if(r != MACH_MSG_SUCCESS) {
+ /* This will fail if the thread dies, but the thread
shouldn't
+ die... */
+ #ifdef BROKEN_EXCEPTION_HANDLING
+ GC_err_printf2(
+ "mach_msg failed with %d %s while sending exc
reply\n",
+ (int)r,mach_error_string(r));
+ #else
+ ABORT("mach_msg failed while sending exception reply");
+ #endif
+ }
+ } /* switch */
+ } /* for(;;) */
+ /* NOT REACHED */
+ return NULL;
+ }
+
+ /* All this SIGBUS code shouldn't be necessary. All protection faults should
+ be going throught the mach exception handler. However, it seems a SIGBUS is
+ occasionally sent for some unknown reason. Even more odd, it seems to be
+ meaningless and safe to ignore. */
+ #ifdef BROKEN_EXCEPTION_HANDLING
+
+ typedef void (* SIG_PF)();
+ static SIG_PF GC_old_bus_handler;
+
+ /* Updates to this aren't atomic, but the SIGBUSs seem pretty rare.
+ Even if this doesn't get updated property, it isn't really a problem */
+ static int GC_sigbus_count;
+
+ static void GC_darwin_sigbus(int num,siginfo_t *sip,void *context) {
+ if(num != SIGBUS) ABORT("Got a non-sigbus signal in the sigbus handler");
+
+ /* Ugh... some seem safe to ignore, but too many in a row probably means
+ trouble. GC_sigbus_count is reset for each mach exception that is
+ handled */
+ if(GC_sigbus_count >= 8) {
+ ABORT("Got more than 8 SIGBUSs in a row!");
+ } else {
+ GC_sigbus_count++;
+ GC_err_printf0("GC: WARNING: Ignoring SIGBUS.\n");
+ }
+ }
+ #endif /* BROKEN_EXCEPTION_HANDLING */
+
+ void GC_dirty_init() {
+ kern_return_t r;
+ mach_port_t me;
+ pthread_t thread;
+ pthread_attr_t attr;
+ exception_mask_t mask;
+
+ # ifdef PRINTSTATS
+ GC_printf0("Inititalizing mach/darwin mprotect virtual dirty bit "
+ "implementation\n");
+ # endif
+ # ifdef BROKEN_EXCEPTION_HANDLING
+ GC_err_printf0("GC: WARNING: Enabling workarounds for various darwin "
+ "exception handling bugs.\n");
+ # endif
+ GC_dirty_maintained = TRUE;
+ if (GC_page_size % HBLKSIZE != 0) {
+ GC_err_printf0("Page size not multiple of HBLKSIZE\n");
+ ABORT("Page size not multiple of HBLKSIZE");
+ }
+
+ GC_task_self = me = mach_task_self();
+
+ r = mach_port_allocate(me,MACH_PORT_RIGHT_RECEIVE,&GC_ports.exception);
+ if(r != KERN_SUCCESS) ABORT("mach_port_allocate failed (exception port)");
+
+ r = mach_port_insert_right(me,GC_ports.exception,GC_ports.exception,
+ MACH_MSG_TYPE_MAKE_SEND);
+ if(r != KERN_SUCCESS)
+ ABORT("mach_port_insert_right failed (exception port)");
+
+ #if defined(THREADS)
+ r = mach_port_allocate(me,MACH_PORT_RIGHT_RECEIVE,&GC_ports.reply);
+ if(r != KERN_SUCCESS) ABORT("mach_port_allocate failed (reply port)");
+ #endif
+
+ /* The exceptions we want to catch */
+ mask = EXC_MASK_BAD_ACCESS;
+
+ r = task_get_exception_ports(
+ me,
+ mask,
+ GC_old_exc_ports.masks,
+ &GC_old_exc_ports.count,
+ GC_old_exc_ports.ports,
+ GC_old_exc_ports.behaviors,
+ GC_old_exc_ports.flavors
+ );
+ if(r != KERN_SUCCESS) ABORT("task_get_exception_ports failed");
+
+ r = task_set_exception_ports(
+ me,
+ mask,
+ GC_ports.exception,
+ EXCEPTION_DEFAULT,
+ MACHINE_THREAD_STATE
+ );
+ if(r != KERN_SUCCESS) ABORT("task_set_exception_ports failed");
+
+ if(pthread_attr_init(&attr) != 0) ABORT("pthread_attr_init failed");
+ if(pthread_attr_setdetachstate(&attr,PTHREAD_CREATE_DETACHED) != 0)
+ ABORT("pthread_attr_setdetachedstate failed");
+
+ # undef pthread_create
+ /* This will call the real pthread function, not our wrapper */
+ if(pthread_create(&thread,&attr,GC_mprotect_thread,NULL) != 0)
+ ABORT("pthread_create failed");
+ pthread_attr_destroy(&attr);
+
+ /* Setup the sigbus handler for ignoring the meaningless SIGBUSs */
+ #ifdef BROKEN_EXCEPTION_HANDLING
+ {
+ struct sigaction sa, oldsa;
+ sa.sa_handler = (SIG_PF)GC_darwin_sigbus;
+ sigemptyset(&sa.sa_mask);
+ sa.sa_flags = SA_RESTART|SA_SIGINFO;
+ if(sigaction(SIGBUS,&sa,&oldsa) < 0) ABORT("sigaction");
+ GC_old_bus_handler = (SIG_PF)oldsa.sa_handler;
+ if (GC_old_bus_handler != SIG_DFL) {
+ # ifdef PRINTSTATS
+ GC_err_printf0("Replaced other SIGBUS handler\n");
+ # endif
+ }
+ }
+ #endif /* BROKEN_EXCEPTION_HANDLING */
+ }
+
+ /* The source code for Apple's GDB was used as a reference for the exception
+ forwarding code. This code is similar to be GDB code only because there is
+ only one way to do it. */
+ static kern_return_t GC_forward_exception(
+ mach_port_t thread,
+ mach_port_t task,
+ exception_type_t exception,
+ exception_data_t data,
+ mach_msg_type_number_t data_count
+ ) {
+ int i;
+ kern_return_t r;
+ mach_port_t port;
+ exception_behavior_t behavior;
+ thread_state_flavor_t flavor;
+
+ thread_state_data_t thread_state;
+ mach_msg_type_number_t thread_state_count = THREAD_STATE_MAX;
+
+ for(i=0;i<GC_old_exc_ports.count;i++)
+ if(GC_old_exc_ports.masks[i] & (1 << exception))
+ break;
+ if(i==GC_old_exc_ports.count) ABORT("No handler for exception!");
+
+ port = GC_old_exc_ports.ports[i];
+ behavior = GC_old_exc_ports.behaviors[i];
+ flavor = GC_old_exc_ports.flavors[i];
+
+ if(behavior != EXCEPTION_DEFAULT) {
+ r = thread_get_state(thread,flavor,thread_state,&thread_state_count);
+ if(r != KERN_SUCCESS)
+ ABORT("thread_get_state failed in forward_exception");
+ }
+
+ switch(behavior) {
+ case EXCEPTION_DEFAULT:
+ r = exception_raise(port,thread,task,exception,data,data_count);
+ break;
+ case EXCEPTION_STATE:
+ r = exception_raise_state(port,thread,task,exception,data,
+ data_count,&flavor,thread_state,thread_state_count,
+ thread_state,&thread_state_count);
+ break;
+ case EXCEPTION_STATE_IDENTITY:
+ r =
exception_raise_state_identity(port,thread,task,exception,data,
+ data_count,&flavor,thread_state,thread_state_count,
+ thread_state,&thread_state_count);
+ break;
+ default:
+ r = KERN_FAILURE; /* make gcc happy */
+ ABORT("forward_exception: unknown behavior");
+ break;
+ }
+
+ if(behavior != EXCEPTION_DEFAULT) {
+ r = thread_set_state(thread,flavor,thread_state,thread_state_count);
+ if(r != KERN_SUCCESS)
+ ABORT("thread_set_state failed in forward_exception");
+ }
+
+ return r;
+ }
+
+ #define FWD() GC_forward_exception(thread,task,exception,code,code_count)
+
+ /* This violates the namespace rules but there isn't anything that can be done
+ about it. The exception handling stuff is hard coded to call this */
+ kern_return_t
+ catch_exception_raise(
+ mach_port_t exception_port,mach_port_t thread,mach_port_t task,
+ exception_type_t exception,exception_data_t code,
+ mach_msg_type_number_t code_count
+ ) {
+ kern_return_t r;
+ char *addr;
+ struct hblk *h;
+ int i;
+ #ifdef POWERPC
+ thread_state_flavor_t flavor = PPC_EXCEPTION_STATE;
+ mach_msg_type_number_t exc_state_count = PPC_EXCEPTION_STATE_COUNT;
+ ppc_exception_state_t exc_state;
+ #else
+ # error FIXME for non-ppc darwin
+ #endif
+
+
+ if(exception != EXC_BAD_ACCESS || code[0] != KERN_PROTECTION_FAILURE) {
+ #ifdef DEBUG_EXCEPTION_HANDLING
+ /* We aren't interested, pass it on to the old handler */
+ GC_printf3("Exception: 0x%x Code: 0x%x 0x%x in catch....\n",
+ exception,
+ code_count > 0 ? code[0] : -1,
+ code_count > 1 ? code[1] : -1);
+ #endif
+ return FWD();
+ }
+
+ r = thread_get_state(thread,flavor,
+ (natural_t*)&exc_state,&exc_state_count);
+ if(r != KERN_SUCCESS) {
+ /* The thread is supposed to be suspended while the exception handler
+ is called. This shouldn't fail. */
+ #ifdef BROKEN_EXCEPTION_HANDLING
+ GC_err_printf0("thread_get_state failed in "
+ "catch_exception_raise\n");
+ return KERN_SUCCESS;
+ #else
+ ABORT("thread_get_state failed in catch_exception_raise");
+ #endif
+ }
+
+ /* This is the address that caused the fault */
+ addr = (char*) exc_state.dar;
+
+ if((HDR(addr)) == 0) {
+ /* Ugh... just like the SIGBUS problem above, it seems we get a bogus
+ KERN_PROTECTION_FAILURE every once and a while. We wait till we get
+ a bunch in a row before doing anything about it. If a "real" fault
+ ever occurres it'll just keep faulting over and over and we'll hit
+ the limit pretty quickly. */
+ #ifdef BROKEN_EXCEPTION_HANDLING
+ static char *last_fault;
+ static int last_fault_count;
+
+ if(addr != last_fault) {
+ last_fault = addr;
+ last_fault_count = 0;
+ }
+ if(++last_fault_count < 32) {
+ if(last_fault_count == 1)
+ GC_err_printf1(
+ "GC: WARNING: Ignoring KERN_PROTECTION_FAILURE at
%p\n",
+ addr);
+ return KERN_SUCCESS;
+ }
+
+ GC_err_printf1("Unexpected KERN_PROTECTION_FAILURE at %p\n",addr);
+ /* Can't pass it along to the signal handler because that is
+ ignoring SIGBUS signals. We also shouldn't call ABORT here as
+ signals don't always work too well from the exception handler.
*/
+ GC_err_printf0("Aborting\n");
+ exit(EXIT_FAILURE);
+ #else /* BROKEN_EXCEPTION_HANDLING */
+ /* Pass it along to the next exception handler
+ (which should call SIGBUS/SIGSEGV) */
+ return FWD();
+ #endif /* !BROKEN_EXCEPTION_HANDLING */
+ }
+
+ #ifdef BROKEN_EXCEPTION_HANDLING
+ /* Reset the number of consecutive SIGBUSs */
+ GC_sigbus_count = 0;
+ #endif
+
+ if(GC_mprotect_state == GC_MP_NORMAL) { /* common case */
+ h = (struct hblk*)((word)addr & ~(GC_page_size-1));
+ UNPROTECT(h, GC_page_size);
+ for (i = 0; i < divHBLKSZ(GC_page_size); i++) {
+ register int index = PHT_HASH(h+i);
+ async_set_pht_entry_from_index(GC_dirty_pages, index);
+ }
+ } else if(GC_mprotect_state == GC_MP_DISCARDING) {
+ /* Lie to the thread for now. No sense UNPROTECT()ing the memory
+ when we're just going to PROTECT() it again later. The thread
+ will just fault again once it resumes */
+ } else {
+ /* Shouldn't happen, i don't think */
+ GC_printf0("KERN_PROTECTION_FAILURE while world is stopped\n");
+ return FWD();
+ }
+ return KERN_SUCCESS;
+ }
+ #undef FWD
+
+ /* These should never be called, but just in case... */
+ kern_return_t catch_exception_raise_state(mach_port_name_t exception_port,
+ int exception, exception_data_t code, mach_msg_type_number_t codeCnt,
+ int flavor, thread_state_t old_state, int old_stateCnt,
+ thread_state_t new_state, int new_stateCnt)
+ {
+ ABORT("catch_exception_raise_state");
+ return(KERN_INVALID_ARGUMENT);
+ }
+ kern_return_t catch_exception_raise_state_identity(
+ mach_port_name_t exception_port, mach_port_t thread, mach_port_t task,
+ int exception, exception_data_t code, mach_msg_type_number_t codeCnt,
+ int flavor, thread_state_t old_state, int old_stateCnt,
+ thread_state_t new_state, int new_stateCnt)
+ {
+ ABORT("catch_exception_raise_state_identity");
+ return(KERN_INVALID_ARGUMENT);
+ }
+
+
+ #endif /* DARWIN && MPROTECT_VDB */
+
+ # ifndef HAVE_INCREMENTAL_PROTECTION_NEEDS
+ int GC_incremental_protection_needs()
+ {
+ return GC_PROTECTS_NONE;
+ }
+ # endif /* !HAVE_INCREMENTAL_PROTECTION_NEEDS */
+
+ /*
+ * Call stack save code for debugging.
+ * Should probably be in mach_dep.c, but that requires reorganization.
+ */
+
+ /* I suspect the following works for most X86 *nix variants, so */
+ /* long as the frame pointer is explicitly stored. In the case of gcc,
*/
+ /* compiler flags (e.g. -fomit-frame-pointer) determine whether it is.
*/
+ #if defined(I386) && defined(LINUX) && defined(SAVE_CALL_CHAIN)
+ # include <features.h>
+
+ struct frame {
+ struct frame *fr_savfp;
+ long fr_savpc;
+ long fr_arg[NARGS]; /* All the arguments go here. */
+ };
+ #endif
+
+ #if defined(SPARC)
+ # if defined(LINUX)
+ # include <features.h>
+
+ struct frame {
+ long fr_local[8];
+ long fr_arg[6];
+ struct frame *fr_savfp;
+ long fr_savpc;
+ # ifndef __arch64__
+ char *fr_stret;
+ # endif
+ long fr_argd[6];
+ long fr_argx[0];
+ };
+ # else
+ # if defined(SUNOS4)
+ # include <machine/frame.h>
+ # else
+ # if defined (DRSNX)
+ # include <sys/sparc/frame.h>
+ # else
+ # if defined(OPENBSD) || defined(NETBSD)
+ # include <frame.h>
+ # else
+ # include <sys/frame.h>
+ # endif
+ # endif
+ # endif
+ # endif
+ # if NARGS > 6
+ --> We only know how to to get the first 6 arguments
+ # endif
+ #endif /* SPARC */
+
+ #ifdef NEED_CALLINFO
+ /* Fill in the pc and argument information for up to NFRAMES of my */
+ /* callers. Ignore my frame and my callers frame. */
+
+ #ifdef LINUX
+ # include <unistd.h>
+ #endif
+
+ #endif /* NEED_CALLINFO */
+
+ #ifdef SAVE_CALL_CHAIN
+
+ #if NARGS == 0 && NFRAMES % 2 == 0 /* No padding */ \
+ && defined(GC_HAVE_BUILTIN_BACKTRACE)
+
+ #include <execinfo.h>
+
+ void GC_save_callers (info)
+ struct callinfo info[NFRAMES];
+ {
+ void * tmp_info[NFRAMES + 1];
+ int npcs, i;
+ # define IGNORE_FRAMES 1
+
+ /* We retrieve NFRAMES+1 pc values, but discard the first, since it */
+ /* points to our own frame. */
+ GC_ASSERT(sizeof(struct callinfo) == sizeof(void *));
+ npcs = backtrace((void **)tmp_info, NFRAMES + IGNORE_FRAMES);
+ BCOPY(tmp_info+IGNORE_FRAMES, info, (npcs - IGNORE_FRAMES) * sizeof(void
*));
+ for (i = npcs - IGNORE_FRAMES; i < NFRAMES; ++i) info[i].ci_pc = 0;
+ }
+
+ #else /* No builtin backtrace; do it ourselves */
+
+ #if (defined(OPENBSD) || defined(NETBSD)) && defined(SPARC)
+ # define FR_SAVFP fr_fp
+ # define FR_SAVPC fr_pc
+ #else
+ # define FR_SAVFP fr_savfp
+ # define FR_SAVPC fr_savpc
+ #endif
+
+ #if defined(SPARC) && (defined(__arch64__) || defined(__sparcv9))
+ # define BIAS 2047
+ #else
+ # define BIAS 0
+ #endif
+
+ void GC_save_callers (info)
+ struct callinfo info[NFRAMES];
+ {
+ struct frame *frame;
+ struct frame *fp;
+ int nframes = 0;
+ # ifdef I386
+ /* We assume this is turned on only with gcc as the compiler. */
+ asm("movl %%ebp,%0" : "=r"(frame));
+ fp = frame;
+ # else
+ frame = (struct frame *) GC_save_regs_in_stack ();
+ fp = (struct frame *)((long) frame -> FR_SAVFP + BIAS);
+ #endif
+
+ for (; (!(fp HOTTER_THAN frame) && !(GC_stackbottom HOTTER_THAN (ptr_t)fp)
+ && (nframes < NFRAMES));
+ fp = (struct frame *)((long) fp -> FR_SAVFP + BIAS), nframes++) {
+ register int i;
+
+ info[nframes].ci_pc = fp->FR_SAVPC;
+ # if NARGS > 0
+ for (i = 0; i < NARGS; i++) {
+ info[nframes].ci_arg[i] = ~(fp->fr_arg[i]);
+ }
+ # endif /* NARGS > 0 */
+ }
+ if (nframes < NFRAMES) info[nframes].ci_pc = 0;
+ }
+
+ #endif /* No builtin backtrace */
+
+ #endif /* SAVE_CALL_CHAIN */
+
+ #ifdef NEED_CALLINFO
+
+ /* Print info to stderr. We do NOT hold the allocation lock */
+ void GC_print_callers (info)
+ struct callinfo info[NFRAMES];
+ {
+ register int i;
+ static int reentry_count = 0;
+ GC_bool stop = FALSE;
+
+ LOCK();
+ ++reentry_count;
+ UNLOCK();
+
+ # if NFRAMES == 1
+ GC_err_printf0("\tCaller at allocation:\n");
+ # else
+ GC_err_printf0("\tCall chain at allocation:\n");
+ # endif
+ for (i = 0; i < NFRAMES && !stop ; i++) {
+ if (info[i].ci_pc == 0) break;
+ # if NARGS > 0
+ {
+ int j;
+
+ GC_err_printf0("\t\targs: ");
+ for (j = 0; j < NARGS; j++) {
+ if (j != 0) GC_err_printf0(", ");
+ GC_err_printf2("%d (0x%X)", ~(info[i].ci_arg[j]),
+ ~(info[i].ci_arg[j]));
+ }
+ GC_err_printf0("\n");
+ }
+ # endif
+ if (reentry_count > 1) {
+ /* We were called during an allocation during */
+ /* a previous GC_print_callers call; punt. */
+ GC_err_printf1("\t\t##PC##= 0x%lx\n", info[i].ci_pc);
+ continue;
+ }
+ {
+ # ifdef LINUX
+ FILE *pipe;
+ # endif
+ # if defined(GC_HAVE_BUILTIN_BACKTRACE)
+ char **sym_name =
+ backtrace_symbols((void **)(&(info[i].ci_pc)), 1);
+ char *name = sym_name[0];
+ # else
+ char buf[40];
+ char *name = buf;
+ sprintf(buf, "##PC##= 0x%lx", info[i].ci_pc);
+ # endif
+ # if defined(LINUX) && !defined(SMALL_CONFIG)
+ /* Try for a line number. */
+ {
+ # define EXE_SZ 100
+ static char exe_name[EXE_SZ];
+ # define CMD_SZ 200
+ char cmd_buf[CMD_SZ];
+ # define RESULT_SZ 200
+ static char result_buf[RESULT_SZ];
+ size_t result_len;
+ static GC_bool found_exe_name = FALSE;
+ static GC_bool will_fail = FALSE;
+ int ret_code;
+ /* Try to get it via a hairy and expensive scheme. */
+ /* First we get the name of the executable: */
+ if (will_fail) goto out;
+ if (!found_exe_name) {
+ ret_code = readlink("/proc/self/exe", exe_name, EXE_SZ);
+ if (ret_code < 0 || ret_code >= EXE_SZ
+ || exe_name[0] != '/') {
+ will_fail = TRUE; /* Dont try again. */
+ goto out;
+ }
+ exe_name[ret_code] = '\0';
+ found_exe_name = TRUE;
+ }
+ /* Then we use popen to start addr2line -e <exe> <addr> */
+ /* There are faster ways to do this, but hopefully this */
+ /* isn't time critical. */
+ sprintf(cmd_buf, "/usr/bin/addr2line -f -e %s 0x%lx", exe_name,
+ (unsigned long)info[i].ci_pc);
+ pipe = popen(cmd_buf, "r");
+ if (pipe == NULL
+ || (result_len = fread(result_buf, 1, RESULT_SZ - 1, pipe))
+ == 0) {
+ if (pipe != NULL) pclose(pipe);
+ will_fail = TRUE;
+ goto out;
+ }
+ if (result_buf[result_len - 1] == '\n') --result_len;
+ result_buf[result_len] = 0;
+ if (result_buf[0] == '?'
+ || result_buf[result_len-2] == ':'
+ && result_buf[result_len-1] == '0') {
+ pclose(pipe);
+ goto out;
+ }
+ /* Get rid of embedded newline, if any. Test for "main" */
+ {
+ char * nl = strchr(result_buf, '\n');
+ if (nl != NULL && nl < result_buf + result_len) {
+ *nl = ':';
+ }
+ if (strncmp(result_buf, "main", nl - result_buf) == 0) {
+ stop = TRUE;
+ }
+ }
+ if (result_len < RESULT_SZ - 25) {
+ /* Add in hex address */
+ sprintf(result_buf + result_len, " [0x%lx]",
+ (unsigned long)info[i].ci_pc);
+ }
+ name = result_buf;
+ pclose(pipe);
+ out:;
+ }
+ # endif /* LINUX */
+ GC_err_printf1("\t\t%s\n", name);
+ # if defined(GC_HAVE_BUILTIN_BACKTRACE)
+ free(sym_name); /* May call GC_free; that's OK */
+ # endif
+ }
+ }
+ LOCK();
+ --reentry_count;
+ UNLOCK();
+ }
+
+ #endif /* NEED_CALLINFO */
+
+
+
+ #if defined(LINUX) && defined(__ELF__) && !defined(SMALL_CONFIG)
+
+ /* Dump /proc/self/maps to GC_stderr, to enable looking up names for
+ addresses in FIND_LEAK output. */
+
+ static word dump_maps(char *maps)
+ {
+ GC_err_write(maps, strlen(maps));
+ return 1;
+ }
+
+ void GC_print_address_map()
+ {
+ GC_err_printf0("---------- Begin address map ----------\n");
+ GC_apply_to_maps(dump_maps);
+ GC_err_printf0("---------- End address map ----------\n");
+ }
+
+ #endif
+
+
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