Imported Upstream version 1.9.3.p194upstream/1.9.3.p194

1 files changed, 3634 insertions, 0 deletions

diff --git a/gc.c b/gc.c
new file mode 100644
index 0000000..064f9a8
--- /dev/null
+++ b/gc.c
@@ -0,0 +1,3634 @@
+/**********************************************************************
+
+  gc.c -
+
+  $Author: naruse $
+  created at: Tue Oct  5 09:44:46 JST 1993
+
+  Copyright (C) 1993-2007 Yukihiro Matsumoto
+  Copyright (C) 2000  Network Applied Communication Laboratory, Inc.
+  Copyright (C) 2000  Information-technology Promotion Agency, Japan
+
+**********************************************************************/
+
+#include "ruby/ruby.h"
+#include "ruby/st.h"
+#include "ruby/re.h"
+#include "ruby/io.h"
+#include "ruby/util.h"
+#include "eval_intern.h"
+#include "vm_core.h"
+#include "internal.h"
+#include "gc.h"
+#include "constant.h"
+#include <stdio.h>
+#include <setjmp.h>
+#include <sys/types.h>
+
+#ifdef HAVE_SYS_TIME_H
+#include <sys/time.h>
+#endif
+
+#ifdef HAVE_SYS_RESOURCE_H
+#include <sys/resource.h>
+#endif
+
+#if defined _WIN32 || defined __CYGWIN__
+#include <windows.h>
+#endif
+
+#ifdef HAVE_VALGRIND_MEMCHECK_H
+# include <valgrind/memcheck.h>
+# ifndef VALGRIND_MAKE_MEM_DEFINED
+#  define VALGRIND_MAKE_MEM_DEFINED(p, n) VALGRIND_MAKE_READABLE((p), (n))
+# endif
+# ifndef VALGRIND_MAKE_MEM_UNDEFINED
+#  define VALGRIND_MAKE_MEM_UNDEFINED(p, n) VALGRIND_MAKE_WRITABLE((p), (n))
+# endif
+#else
+# define VALGRIND_MAKE_MEM_DEFINED(p, n) /* empty */
+# define VALGRIND_MAKE_MEM_UNDEFINED(p, n) /* empty */
+#endif
+
+#define rb_setjmp(env) RUBY_SETJMP(env)
+#define rb_jmp_buf rb_jmpbuf_t
+
+/* Make alloca work the best possible way.  */
+#ifdef __GNUC__
+# ifndef atarist
+#  ifndef alloca
+#   define alloca __builtin_alloca
+#  endif
+# endif /* atarist */
+#else
+# ifdef HAVE_ALLOCA_H
+#  include <alloca.h>
+# else
+#  ifdef _AIX
+ #pragma alloca
+#  else
+#   ifndef alloca /* predefined by HP cc +Olibcalls */
+void *alloca ();
+#   endif
+#  endif /* AIX */
+# endif /* HAVE_ALLOCA_H */
+#endif /* __GNUC__ */
+
+#ifndef GC_MALLOC_LIMIT
+#define GC_MALLOC_LIMIT 8000000
+#endif
+#define HEAP_MIN_SLOTS 10000
+#define FREE_MIN  4096
+
+typedef struct {
+    unsigned int initial_malloc_limit;
+    unsigned int initial_heap_min_slots;
+    unsigned int initial_free_min;
+    int gc_stress;
+} ruby_gc_params_t;
+
+ruby_gc_params_t initial_params = {
+    GC_MALLOC_LIMIT,
+    HEAP_MIN_SLOTS,
+    FREE_MIN,
+#if defined(ENABLE_VM_OBJSPACE) && ENABLE_VM_OBJSPACE
+    FALSE,
+#endif
+};
+
+#define nomem_error GET_VM()->special_exceptions[ruby_error_nomemory]
+
+#define MARK_STACK_MAX 1024
+
+int ruby_gc_debug_indent = 0;
+
+/* for GC profile */
+#define GC_PROFILE_MORE_DETAIL 0
+typedef struct gc_profile_record {
+    double gc_time;
+    double gc_mark_time;
+    double gc_sweep_time;
+    double gc_invoke_time;
+
+    size_t heap_use_slots;
+    size_t heap_live_objects;
+    size_t heap_free_objects;
+    size_t heap_total_objects;
+    size_t heap_use_size;
+    size_t heap_total_size;
+
+    int have_finalize;
+    int is_marked;
+
+    size_t allocate_increase;
+    size_t allocate_limit;
+} gc_profile_record;
+
+static double
+getrusage_time(void)
+{
+#ifdef RUSAGE_SELF
+    struct rusage usage;
+    struct timeval time;
+    getrusage(RUSAGE_SELF, &usage);
+    time = usage.ru_utime;
+    return time.tv_sec + time.tv_usec * 1e-6;
+#elif defined _WIN32
+    FILETIME creation_time, exit_time, kernel_time, user_time;
+    ULARGE_INTEGER ui;
+    LONG_LONG q;
+    double t;
+
+    if (GetProcessTimes(GetCurrentProcess(),
+			&creation_time, &exit_time, &kernel_time, &user_time) == 0)
+    {
+	return 0.0;
+    }
+    memcpy(&ui, &user_time, sizeof(FILETIME));
+    q = ui.QuadPart / 10L;
+    t = (DWORD)(q % 1000000L) * 1e-6;
+    q /= 1000000L;
+#ifdef __GNUC__
+    t += q;
+#else
+    t += (double)(DWORD)(q >> 16) * (1 << 16);
+    t += (DWORD)q & ~(~0 << 16);
+#endif
+    return t;
+#else
+    return 0.0;
+#endif
+}
+
+#define GC_PROF_TIMER_START do {\
+	if (objspace->profile.run) {\
+	    if (!objspace->profile.record) {\
+		objspace->profile.size = 1000;\
+		objspace->profile.record = malloc(sizeof(gc_profile_record) * objspace->profile.size);\
+	    }\
+	    if (count >= objspace->profile.size) {\
+		objspace->profile.size += 1000;\
+		objspace->profile.record = realloc(objspace->profile.record, sizeof(gc_profile_record) * objspace->profile.size);\
+	    }\
+	    if (!objspace->profile.record) {\
+		rb_bug("gc_profile malloc or realloc miss");\
+	    }\
+	    MEMZERO(&objspace->profile.record[count], gc_profile_record, 1);\
+	    gc_time = getrusage_time();\
+	    objspace->profile.record[count].gc_invoke_time = gc_time - objspace->profile.invoke_time;\
+	}\
+    } while(0)
+
+#define GC_PROF_TIMER_STOP(marked) do {\
+	if (objspace->profile.run) {\
+	    gc_time = getrusage_time() - gc_time;\
+	    if (gc_time < 0) gc_time = 0;\
+	    objspace->profile.record[count].gc_time = gc_time;\
+	    objspace->profile.record[count].is_marked = !!(marked);\
+	    GC_PROF_SET_HEAP_INFO(objspace->profile.record[count]);\
+	    objspace->profile.count++;\
+	}\
+    } while(0)
+
+#if GC_PROFILE_MORE_DETAIL
+#define INIT_GC_PROF_PARAMS double gc_time = 0, sweep_time = 0;\
+    size_t count = objspace->profile.count, total = 0, live = 0
+
+#define GC_PROF_MARK_TIMER_START double mark_time = 0;\
+    do {\
+	if (objspace->profile.run) {\
+	    mark_time = getrusage_time();\
+	}\
+    } while(0)
+
+#define GC_PROF_MARK_TIMER_STOP do {\
+	if (objspace->profile.run) {\
+	    mark_time = getrusage_time() - mark_time;\
+	    if (mark_time < 0) mark_time = 0;\
+	    objspace->profile.record[objspace->profile.count].gc_mark_time = mark_time;\
+	}\
+    } while(0)
+
+#define GC_PROF_SWEEP_TIMER_START do {\
+	if (objspace->profile.run) {\
+	    sweep_time = getrusage_time();\
+	}\
+    } while(0)
+
+#define GC_PROF_SWEEP_TIMER_STOP do {\
+	if (objspace->profile.run) {\
+	    sweep_time = getrusage_time() - sweep_time;\
+	    if (sweep_time < 0) sweep_time = 0;\
+	    objspace->profile.record[count].gc_sweep_time = sweep_time;\
+	}\
+    } while(0)
+#define GC_PROF_SET_MALLOC_INFO do {\
+	if (objspace->profile.run) {\
+	    gc_profile_record *record = &objspace->profile.record[objspace->profile.count];\
+	    record->allocate_increase = malloc_increase;\
+	    record->allocate_limit = malloc_limit; \
+	}\
+    } while(0)
+#define GC_PROF_SET_HEAP_INFO(record) do {\
+        live = objspace->heap.live_num;\
+        total = heaps_used * HEAP_OBJ_LIMIT;\
+        (record).heap_use_slots = heaps_used;\
+        (record).heap_live_objects = live;\
+        (record).heap_free_objects = total - live;\
+        (record).heap_total_objects = total;\
+        (record).have_finalize = deferred_final_list ? Qtrue : Qfalse;\
+        (record).heap_use_size = live * sizeof(RVALUE);\
+        (record).heap_total_size = total * sizeof(RVALUE);\
+    } while(0)
+#define GC_PROF_INC_LIVE_NUM objspace->heap.live_num++
+#define GC_PROF_DEC_LIVE_NUM objspace->heap.live_num--
+#else
+#define INIT_GC_PROF_PARAMS double gc_time = 0;\
+    size_t count = objspace->profile.count, total = 0, live = 0
+#define GC_PROF_MARK_TIMER_START
+#define GC_PROF_MARK_TIMER_STOP
+#define GC_PROF_SWEEP_TIMER_START
+#define GC_PROF_SWEEP_TIMER_STOP
+#define GC_PROF_SET_MALLOC_INFO
+#define GC_PROF_SET_HEAP_INFO(record) do {\
+        live = objspace->heap.live_num;\
+        total = heaps_used * HEAP_OBJ_LIMIT;\
+        (record).heap_total_objects = total;\
+        (record).heap_use_size = live * sizeof(RVALUE);\
+        (record).heap_total_size = total * sizeof(RVALUE);\
+    } while(0)
+#define GC_PROF_INC_LIVE_NUM
+#define GC_PROF_DEC_LIVE_NUM
+#endif
+
+
+#if defined(_MSC_VER) || defined(__BORLANDC__) || defined(__CYGWIN__)
+#pragma pack(push, 1) /* magic for reducing sizeof(RVALUE): 24 -> 20 */
+#endif
+
+typedef struct RVALUE {
+    union {
+	struct {
+	    VALUE flags;		/* always 0 for freed obj */
+	    struct RVALUE *next;
+	} free;
+	struct RBasic  basic;
+	struct RObject object;
+	struct RClass  klass;
+	struct RFloat  flonum;
+	struct RString string;
+	struct RArray  array;
+	struct RRegexp regexp;
+	struct RHash   hash;
+	struct RData   data;
+	struct RTypedData   typeddata;
+	struct RStruct rstruct;
+	struct RBignum bignum;
+	struct RFile   file;
+	struct RNode   node;
+	struct RMatch  match;
+	struct RRational rational;
+	struct RComplex complex;
+    } as;
+#ifdef GC_DEBUG
+    const char *file;
+    int   line;
+#endif
+} RVALUE;
+
+#if defined(_MSC_VER) || defined(__BORLANDC__) || defined(__CYGWIN__)
+#pragma pack(pop)
+#endif
+
+struct heaps_slot {
+    void *membase;
+    RVALUE *slot;
+    size_t limit;
+    struct heaps_slot *next;
+    struct heaps_slot *prev;
+};
+
+struct sorted_heaps_slot {
+    RVALUE *start;
+    RVALUE *end;
+    struct heaps_slot *slot;
+};
+
+struct gc_list {
+    VALUE *varptr;
+    struct gc_list *next;
+};
+
+#define CALC_EXACT_MALLOC_SIZE 0
+
+typedef struct rb_objspace {
+    struct {
+	size_t limit;
+	size_t increase;
+#if CALC_EXACT_MALLOC_SIZE
+	size_t allocated_size;
+	size_t allocations;
+#endif
+    } malloc_params;
+    struct {
+	size_t increment;
+	struct heaps_slot *ptr;
+	struct heaps_slot *sweep_slots;
+	struct sorted_heaps_slot *sorted;
+	size_t length;
+	size_t used;
+	RVALUE *freelist;
+	RVALUE *range[2];
+	RVALUE *freed;
+	size_t live_num;
+	size_t free_num;
+	size_t free_min;
+	size_t final_num;
+	size_t do_heap_free;
+    } heap;
+    struct {
+	int dont_gc;
+	int dont_lazy_sweep;
+	int during_gc;
+    } flags;
+    struct {
+	st_table *table;
+	RVALUE *deferred;
+    } final;
+    struct {
+	VALUE buffer[MARK_STACK_MAX];
+	VALUE *ptr;
+	int overflow;
+    } markstack;
+    struct {
+	int run;
+	gc_profile_record *record;
+	size_t count;
+	size_t size;
+	double invoke_time;
+    } profile;
+    struct gc_list *global_list;
+    size_t count;
+    int gc_stress;
+} rb_objspace_t;
+
+#if defined(ENABLE_VM_OBJSPACE) && ENABLE_VM_OBJSPACE
+#define rb_objspace (*GET_VM()->objspace)
+#define ruby_initial_gc_stress	initial_params.gc_stress
+int *ruby_initial_gc_stress_ptr = &ruby_initial_gc_stress;
+#else
+static rb_objspace_t rb_objspace = {{GC_MALLOC_LIMIT}, {HEAP_MIN_SLOTS}};
+int *ruby_initial_gc_stress_ptr = &rb_objspace.gc_stress;
+#endif
+#define malloc_limit		objspace->malloc_params.limit
+#define malloc_increase 	objspace->malloc_params.increase
+#define heaps			objspace->heap.ptr
+#define heaps_length		objspace->heap.length
+#define heaps_used		objspace->heap.used
+#define freelist		objspace->heap.freelist
+#define lomem			objspace->heap.range[0]
+#define himem			objspace->heap.range[1]
+#define heaps_inc		objspace->heap.increment
+#define heaps_freed		objspace->heap.freed
+#define dont_gc 		objspace->flags.dont_gc
+#define during_gc		objspace->flags.during_gc
+#define finalizer_table 	objspace->final.table
+#define deferred_final_list	objspace->final.deferred
+#define mark_stack		objspace->markstack.buffer
+#define mark_stack_ptr		objspace->markstack.ptr
+#define mark_stack_overflow	objspace->markstack.overflow
+#define global_List		objspace->global_list
+#define ruby_gc_stress		objspace->gc_stress
+#define initial_malloc_limit	initial_params.initial_malloc_limit
+#define initial_heap_min_slots	initial_params.initial_heap_min_slots
+#define initial_free_min	initial_params.initial_free_min
+
+static void rb_objspace_call_finalizer(rb_objspace_t *objspace);
+
+#if defined(ENABLE_VM_OBJSPACE) && ENABLE_VM_OBJSPACE
+rb_objspace_t *
+rb_objspace_alloc(void)
+{
+    rb_objspace_t *objspace = malloc(sizeof(rb_objspace_t));
+    memset(objspace, 0, sizeof(*objspace));
+    malloc_limit = initial_malloc_limit;
+    ruby_gc_stress = ruby_initial_gc_stress;
+
+    return objspace;
+}
+#endif
+
+static void initial_expand_heap(rb_objspace_t *objspace);
+
+void
+rb_gc_set_params(void)
+{
+    char *malloc_limit_ptr, *heap_min_slots_ptr, *free_min_ptr;
+
+    if (rb_safe_level() > 0) return;
+
+    malloc_limit_ptr = getenv("RUBY_GC_MALLOC_LIMIT");
+    if (malloc_limit_ptr != NULL) {
+	int malloc_limit_i = atoi(malloc_limit_ptr);
+	if (RTEST(ruby_verbose))
+	    fprintf(stderr, "malloc_limit=%d (%d)\n",
+		    malloc_limit_i, initial_malloc_limit);
+	if (malloc_limit_i > 0) {
+	    initial_malloc_limit = malloc_limit_i;
+	}
+    }
+
+    heap_min_slots_ptr = getenv("RUBY_HEAP_MIN_SLOTS");
+    if (heap_min_slots_ptr != NULL) {
+	int heap_min_slots_i = atoi(heap_min_slots_ptr);
+	if (RTEST(ruby_verbose))
+	    fprintf(stderr, "heap_min_slots=%d (%d)\n",
+		    heap_min_slots_i, initial_heap_min_slots);
+	if (heap_min_slots_i > 0) {
+	    initial_heap_min_slots = heap_min_slots_i;
+            initial_expand_heap(&rb_objspace);
+	}
+    }
+
+    free_min_ptr = getenv("RUBY_FREE_MIN");
+    if (free_min_ptr != NULL) {
+	int free_min_i = atoi(free_min_ptr);
+	if (RTEST(ruby_verbose))
+	    fprintf(stderr, "free_min=%d (%d)\n", free_min_i, initial_free_min);
+	if (free_min_i > 0) {
+	    initial_free_min = free_min_i;
+	}
+    }
+}
+
+#if defined(ENABLE_VM_OBJSPACE) && ENABLE_VM_OBJSPACE
+static void gc_sweep(rb_objspace_t *);
+static void slot_sweep(rb_objspace_t *, struct heaps_slot *);
+static void rest_sweep(rb_objspace_t *);
+
+void
+rb_objspace_free(rb_objspace_t *objspace)
+{
+    rest_sweep(objspace);
+    if (objspace->profile.record) {
+	free(objspace->profile.record);
+	objspace->profile.record = 0;
+    }
+    if (global_List) {
+	struct gc_list *list, *next;
+	for (list = global_List; list; list = next) {
+	    next = list->next;
+	    free(list);
+	}
+    }
+    if (objspace->heap.sorted) {
+	size_t i;
+	for (i = 0; i < heaps_used; ++i) {
+	    free(objspace->heap.sorted[i].slot->membase);
+	    free(objspace->heap.sorted[i].slot);
+	}
+	free(objspace->heap.sorted);
+	heaps_used = 0;
+	heaps = 0;
+    }
+    free(objspace);
+}
+#endif
+
+/* tiny heap size */
+/* 32KB */
+/*#define HEAP_SIZE 0x8000 */
+/* 128KB */
+/*#define HEAP_SIZE 0x20000 */
+/* 64KB */
+/*#define HEAP_SIZE 0x10000 */
+/* 16KB */
+#define HEAP_SIZE 0x4000
+/* 8KB */
+/*#define HEAP_SIZE 0x2000 */
+/* 4KB */
+/*#define HEAP_SIZE 0x1000 */
+/* 2KB */
+/*#define HEAP_SIZE 0x800 */
+
+#define HEAP_OBJ_LIMIT (unsigned int)(HEAP_SIZE / sizeof(struct RVALUE))
+
+extern st_table *rb_class_tbl;
+
+int ruby_disable_gc_stress = 0;
+
+static void run_final(rb_objspace_t *objspace, VALUE obj);
+static int garbage_collect(rb_objspace_t *objspace);
+static int gc_lazy_sweep(rb_objspace_t *objspace);
+
+void
+rb_global_variable(VALUE *var)
+{
+    rb_gc_register_address(var);
+}
+
+static void *
+ruby_memerror_body(void *dummy)
+{
+    rb_memerror();
+    return 0;
+}
+
+static void
+ruby_memerror(void)
+{
+    if (ruby_thread_has_gvl_p()) {
+	rb_memerror();
+    }
+    else {
+	if (ruby_native_thread_p()) {
+	    rb_thread_call_with_gvl(ruby_memerror_body, 0);
+	}
+	else {
+	    /* no ruby thread */
+	    fprintf(stderr, "[FATAL] failed to allocate memory\n");
+	    exit(EXIT_FAILURE);
+	}
+    }
+}
+
+void
+rb_memerror(void)
+{
+    rb_thread_t *th = GET_THREAD();
+    if (!nomem_error ||
+	(rb_thread_raised_p(th, RAISED_NOMEMORY) && rb_safe_level() < 4)) {
+	fprintf(stderr, "[FATAL] failed to allocate memory\n");
+	exit(EXIT_FAILURE);
+    }
+    if (rb_thread_raised_p(th, RAISED_NOMEMORY)) {
+	rb_thread_raised_clear(th);
+	GET_THREAD()->errinfo = nomem_error;
+	JUMP_TAG(TAG_RAISE);
+    }
+    rb_thread_raised_set(th, RAISED_NOMEMORY);
+    rb_exc_raise(nomem_error);
+}
+
+/*
+ *  call-seq:
+ *    GC.stress                 -> true or false
+ *
+ *  returns current status of GC stress mode.
+ */
+
+static VALUE
+gc_stress_get(VALUE self)
+{
+    rb_objspace_t *objspace = &rb_objspace;
+    return ruby_gc_stress ? Qtrue : Qfalse;
+}
+
+/*
+ *  call-seq:
+ *    GC.stress = bool          -> bool
+ *
+ *  Updates the GC stress mode.
+ *
+ *  When stress mode is enabled the GC is invoked at every GC opportunity:
+ *  all memory and object allocations.
+ *
+ *  Enabling stress mode makes Ruby very slow, it is only for debugging.
+ */
+
+static VALUE
+gc_stress_set(VALUE self, VALUE flag)
+{
+    rb_objspace_t *objspace = &rb_objspace;
+    rb_secure(2);
+    ruby_gc_stress = RTEST(flag);
+    return flag;
+}
+
+/*
+ *  call-seq:
+ *    GC::Profiler.enable?                 -> true or false
+ *
+ *  The current status of GC profile mode.
+ */
+
+static VALUE
+gc_profile_enable_get(VALUE self)
+{
+    rb_objspace_t *objspace = &rb_objspace;
+    return objspace->profile.run;
+}
+
+/*
+ *  call-seq:
+ *    GC::Profiler.enable          -> nil
+ *
+ *  Starts the GC profiler.
+ *
+ */
+
+static VALUE
+gc_profile_enable(void)
+{
+    rb_objspace_t *objspace = &rb_objspace;
+
+    objspace->profile.run = TRUE;
+    return Qnil;
+}
+
+/*
+ *  call-seq:
+ *    GC::Profiler.disable          -> nil
+ *
+ *  Stops the GC profiler.
+ *
+ */
+
+static VALUE
+gc_profile_disable(void)
+{
+    rb_objspace_t *objspace = &rb_objspace;
+
+    objspace->profile.run = FALSE;
+    return Qnil;
+}
+
+/*
+ *  call-seq:
+ *    GC::Profiler.clear          -> nil
+ *
+ *  Clears the GC profiler data.
+ *
+ */
+
+static VALUE
+gc_profile_clear(void)
+{
+    rb_objspace_t *objspace = &rb_objspace;
+    MEMZERO(objspace->profile.record, gc_profile_record, objspace->profile.size);
+    objspace->profile.count = 0;
+    return Qnil;
+}
+
+static void *
+negative_size_allocation_error_with_gvl(void *ptr)
+{
+    rb_raise(rb_eNoMemError, "%s", (const char *)ptr);
+    return 0; /* should not be reached */
+}
+
+static void
+negative_size_allocation_error(const char *msg)
+{
+    if (ruby_thread_has_gvl_p()) {
+	rb_raise(rb_eNoMemError, "%s", msg);
+    }
+    else {
+	if (ruby_native_thread_p()) {
+	    rb_thread_call_with_gvl(negative_size_allocation_error_with_gvl, (void *)msg);
+	}
+	else {
+	    fprintf(stderr, "[FATAL] %s\n", msg);
+	    exit(EXIT_FAILURE);
+	}
+    }
+}
+
+static void *
+gc_with_gvl(void *ptr)
+{
+    return (void *)(VALUE)garbage_collect((rb_objspace_t *)ptr);
+}
+
+static int
+garbage_collect_with_gvl(rb_objspace_t *objspace)
+{
+    if (dont_gc) return TRUE;
+    if (ruby_thread_has_gvl_p()) {
+	return garbage_collect(objspace);
+    }
+    else {
+	if (ruby_native_thread_p()) {
+	    return (int)(VALUE)rb_thread_call_with_gvl(gc_with_gvl, (void *)objspace);
+	}
+	else {
+	    /* no ruby thread */
+	    fprintf(stderr, "[FATAL] failed to allocate memory\n");
+	    exit(EXIT_FAILURE);
+	}
+    }
+}
+
+static void vm_xfree(rb_objspace_t *objspace, void *ptr);
+
+static inline size_t
+vm_malloc_prepare(rb_objspace_t *objspace, size_t size)
+{
+    if ((ssize_t)size < 0) {
+	negative_size_allocation_error("negative allocation size (or too big)");
+    }
+    if (size == 0) size = 1;
+
+#if CALC_EXACT_MALLOC_SIZE
+    size += sizeof(size_t);
+#endif
+
+    if ((ruby_gc_stress && !ruby_disable_gc_stress) ||
+	(malloc_increase+size) > malloc_limit) {
+	garbage_collect_with_gvl(objspace);
+    }
+
+    return size;
+}
+
+static inline void *
+vm_malloc_fixup(rb_objspace_t *objspace, void *mem, size_t size)
+{
+    malloc_increase += size;
+
+#if CALC_EXACT_MALLOC_SIZE
+    objspace->malloc_params.allocated_size += size;
+    objspace->malloc_params.allocations++;
+    ((size_t *)mem)[0] = size;
+    mem = (size_t *)mem + 1;
+#endif
+
+    return mem;
+}
+
+#define TRY_WITH_GC(alloc) do { \
+	if (!(alloc) && \
+	    (!garbage_collect_with_gvl(objspace) || \
+	     !(alloc))) { \
+	    ruby_memerror(); \
+	} \
+    } while (0)
+
+static void *
+vm_xmalloc(rb_objspace_t *objspace, size_t size)
+{
+    void *mem;
+
+    size = vm_malloc_prepare(objspace, size);
+    TRY_WITH_GC(mem = malloc(size));
+    return vm_malloc_fixup(objspace, mem, size);
+}
+
+static void *
+vm_xrealloc(rb_objspace_t *objspace, void *ptr, size_t size)
+{
+    void *mem;
+
+    if ((ssize_t)size < 0) {
+	negative_size_allocation_error("negative re-allocation size");
+    }
+    if (!ptr) return vm_xmalloc(objspace, size);
+    if (size == 0) {
+	vm_xfree(objspace, ptr);
+	return 0;
+    }
+    if (ruby_gc_stress && !ruby_disable_gc_stress)
+	garbage_collect_with_gvl(objspace);
+
+#if CALC_EXACT_MALLOC_SIZE
+    size += sizeof(size_t);
+    objspace->malloc_params.allocated_size -= size;
+    ptr = (size_t *)ptr - 1;
+#endif
+
+    mem = realloc(ptr, size);
+    if (!mem) {
+	if (garbage_collect_with_gvl(objspace)) {
+	    mem = realloc(ptr, size);
+	}
+	if (!mem) {
+	    ruby_memerror();
+        }
+    }
+    malloc_increase += size;
+
+#if CALC_EXACT_MALLOC_SIZE
+    objspace->malloc_params.allocated_size += size;
+    ((size_t *)mem)[0] = size;
+    mem = (size_t *)mem + 1;
+#endif
+
+    return mem;
+}
+
+static void
+vm_xfree(rb_objspace_t *objspace, void *ptr)
+{
+#if CALC_EXACT_MALLOC_SIZE
+    size_t size;
+    ptr = ((size_t *)ptr) - 1;
+    size = ((size_t*)ptr)[0];
+    objspace->malloc_params.allocated_size -= size;
+    objspace->malloc_params.allocations--;
+#endif
+
+    free(ptr);
+}
+
+void *
+ruby_xmalloc(size_t size)
+{
+    return vm_xmalloc(&rb_objspace, size);
+}
+
+static inline size_t
+xmalloc2_size(size_t n, size_t size)
+{
+    size_t len = size * n;
+    if (n != 0 && size != len / n) {
+	rb_raise(rb_eArgError, "malloc: possible integer overflow");
+    }
+    return len;
+}
+
+void *
+ruby_xmalloc2(size_t n, size_t size)
+{
+    return vm_xmalloc(&rb_objspace, xmalloc2_size(n, size));
+}
+
+static void *
+vm_xcalloc(rb_objspace_t *objspace, size_t count, size_t elsize)
+{
+    void *mem;
+    size_t size;
+
+    size = xmalloc2_size(count, elsize);
+    size = vm_malloc_prepare(objspace, size);
+
+    TRY_WITH_GC(mem = calloc(1, size));
+    return vm_malloc_fixup(objspace, mem, size);
+}
+
+void *
+ruby_xcalloc(size_t n, size_t size)
+{
+    return vm_xcalloc(&rb_objspace, n, size);
+}
+
+void *
+ruby_xrealloc(void *ptr, size_t size)
+{
+    return vm_xrealloc(&rb_objspace, ptr, size);
+}
+
+void *
+ruby_xrealloc2(void *ptr, size_t n, size_t size)
+{
+    size_t len = size * n;
+    if (n != 0 && size != len / n) {
+	rb_raise(rb_eArgError, "realloc: possible integer overflow");
+    }
+    return ruby_xrealloc(ptr, len);
+}
+
+void
+ruby_xfree(void *x)
+{
+    if (x)
+	vm_xfree(&rb_objspace, x);
+}
+
+
+/*
+ *  call-seq:
+ *     GC.enable    -> true or false
+ *
+ *  Enables garbage collection, returning <code>true</code> if garbage
+ *  collection was previously disabled.
+ *
+ *     GC.disable   #=> false
+ *     GC.enable    #=> true
+ *     GC.enable    #=> false
+ *
+ */
+
+VALUE
+rb_gc_enable(void)
+{
+    rb_objspace_t *objspace = &rb_objspace;
+    int old = dont_gc;
+
+    dont_gc = FALSE;
+    return old ? Qtrue : Qfalse;
+}
+
+/*
+ *  call-seq:
+ *     GC.disable    -> true or false
+ *
+ *  Disables garbage collection, returning <code>true</code> if garbage
+ *  collection was already disabled.
+ *
+ *     GC.disable   #=> false
+ *     GC.disable   #=> true
+ *
+ */
+
+VALUE
+rb_gc_disable(void)
+{
+    rb_objspace_t *objspace = &rb_objspace;
+    int old = dont_gc;
+
+    dont_gc = TRUE;
+    return old ? Qtrue : Qfalse;
+}
+
+VALUE rb_mGC;
+
+void
+rb_gc_register_mark_object(VALUE obj)
+{
+    VALUE ary = GET_THREAD()->vm->mark_object_ary;
+    rb_ary_push(ary, obj);
+}
+
+void
+rb_gc_register_address(VALUE *addr)
+{
+    rb_objspace_t *objspace = &rb_objspace;
+    struct gc_list *tmp;
+
+    tmp = ALLOC(struct gc_list);
+    tmp->next = global_List;
+    tmp->varptr = addr;
+    global_List = tmp;
+}
+
+void
+rb_gc_unregister_address(VALUE *addr)
+{
+    rb_objspace_t *objspace = &rb_objspace;
+    struct gc_list *tmp = global_List;
+
+    if (tmp->varptr == addr) {
+	global_List = tmp->next;
+	xfree(tmp);
+	return;
+    }
+    while (tmp->next) {
+	if (tmp->next->varptr == addr) {
+	    struct gc_list *t = tmp->next;
+
+	    tmp->next = tmp->next->next;
+	    xfree(t);
+	    break;
+	}
+	tmp = tmp->next;
+    }
+}
+
+
+static void
+allocate_sorted_heaps(rb_objspace_t *objspace, size_t next_heaps_length)
+{
+    struct sorted_heaps_slot *p;
+    size_t size;
+
+    size = next_heaps_length*sizeof(struct sorted_heaps_slot);
+
+    if (heaps_used > 0) {
+	p = (struct sorted_heaps_slot *)realloc(objspace->heap.sorted, size);
+	if (p) objspace->heap.sorted = p;
+    }
+    else {
+	p = objspace->heap.sorted = (struct sorted_heaps_slot *)malloc(size);
+    }
+
+    if (p == 0) {
+	during_gc = 0;
+	rb_memerror();
+    }
+    heaps_length = next_heaps_length;
+}
+
+static void
+assign_heap_slot(rb_objspace_t *objspace)
+{
+    RVALUE *p, *pend, *membase;
+    struct heaps_slot *slot;
+    size_t hi, lo, mid;
+    size_t objs;
+
+    objs = HEAP_OBJ_LIMIT;
+    p = (RVALUE*)malloc(HEAP_SIZE);
+    if (p == 0) {
+	during_gc = 0;
+	rb_memerror();
+    }
+    slot = (struct heaps_slot *)malloc(sizeof(struct heaps_slot));
+    if (slot == 0) {
+	xfree(p);
+	during_gc = 0;
+	rb_memerror();
+    }
+    MEMZERO((void*)slot, struct heaps_slot, 1);
+
+    slot->next = heaps;
+    if (heaps) heaps->prev = slot;
+    heaps = slot;
+
+    membase = p;
+    if ((VALUE)p % sizeof(RVALUE) != 0) {
+	p = (RVALUE*)((VALUE)p + sizeof(RVALUE) - ((VALUE)p % sizeof(RVALUE)));
+	if ((HEAP_SIZE - HEAP_OBJ_LIMIT * sizeof(RVALUE)) < (size_t)((char*)p - (char*)membase)) {
+	    objs--;
+	}
+    }
+
+    lo = 0;
+    hi = heaps_used;
+    while (lo < hi) {
+	register RVALUE *mid_membase;
+	mid = (lo + hi) / 2;
+	mid_membase = objspace->heap.sorted[mid].slot->membase;
+	if (mid_membase < membase) {
+	    lo = mid + 1;
+	}
+	else if (mid_membase > membase) {
+	    hi = mid;
+	}
+	else {
+	    rb_bug("same heap slot is allocated: %p at %"PRIuVALUE, (void *)membase, (VALUE)mid);
+	}
+    }
+    if (hi < heaps_used) {
+	MEMMOVE(&objspace->heap.sorted[hi+1], &objspace->heap.sorted[hi], struct sorted_heaps_slot, heaps_used - hi);
+    }
+    objspace->heap.sorted[hi].slot = slot;
+    objspace->heap.sorted[hi].start = p;
+    objspace->heap.sorted[hi].end = (p + objs);
+    heaps->membase = membase;
+    heaps->slot = p;
+    heaps->limit = objs;
+    objspace->heap.free_num += objs;
+    pend = p + objs;
+    if (lomem == 0 || lomem > p) lomem = p;
+    if (himem < pend) himem = pend;
+    heaps_used++;
+
+    while (p < pend) {
+	p->as.free.flags = 0;
+	p->as.free.next = freelist;
+	freelist = p;
+	p++;
+    }
+}
+
+static void
+add_heap_slots(rb_objspace_t *objspace, size_t add)
+{
+    size_t i;
+
+    if ((heaps_used + add) > heaps_length) {
+        allocate_sorted_heaps(objspace, heaps_used + add);
+    }
+
+    for (i = 0; i < add; i++) {
+        assign_heap_slot(objspace);
+    }
+    heaps_inc = 0;
+}
+
+static void
+init_heap(rb_objspace_t *objspace)
+{
+    add_heap_slots(objspace, HEAP_MIN_SLOTS / HEAP_OBJ_LIMIT);
+#ifdef USE_SIGALTSTACK
+    {
+	/* altstack of another threads are allocated in another place */
+	rb_thread_t *th = GET_THREAD();
+	void *tmp = th->altstack;
+	th->altstack = malloc(ALT_STACK_SIZE);
+	free(tmp); /* free previously allocated area */
+    }
+#endif
+
+    objspace->profile.invoke_time = getrusage_time();
+    finalizer_table = st_init_numtable();
+}
+
+static void
+initial_expand_heap(rb_objspace_t *objspace)
+{
+    size_t min_size = initial_heap_min_slots / HEAP_OBJ_LIMIT;
+
+    if (min_size > heaps_used) {
+        add_heap_slots(objspace, min_size - heaps_used);
+    }
+}
+
+static void
+set_heaps_increment(rb_objspace_t *objspace)
+{
+    size_t next_heaps_length = (size_t)(heaps_used * 1.8);
+
+    if (next_heaps_length == heaps_used) {
+        next_heaps_length++;
+    }
+
+    heaps_inc = next_heaps_length - heaps_used;
+
+    if (next_heaps_length > heaps_length) {
+	allocate_sorted_heaps(objspace, next_heaps_length);
+    }
+}
+
+static int
+heaps_increment(rb_objspace_t *objspace)
+{
+    if (heaps_inc > 0) {
+        assign_heap_slot(objspace);
+	heaps_inc--;
+	return TRUE;
+    }
+    return FALSE;
+}
+
+int
+rb_during_gc(void)
+{
+    rb_objspace_t *objspace = &rb_objspace;
+    return during_gc;
+}
+
+#define RANY(o) ((RVALUE*)(o))
+
+VALUE
+rb_newobj(void)
+{
+    rb_objspace_t *objspace = &rb_objspace;
+    VALUE obj;
+
+    if (UNLIKELY(during_gc)) {
+	dont_gc = 1;
+	during_gc = 0;
+	rb_bug("object allocation during garbage collection phase");
+    }
+
+    if (UNLIKELY(ruby_gc_stress && !ruby_disable_gc_stress)) {
+	if (!garbage_collect(objspace)) {
+	    during_gc = 0;
+	    rb_memerror();
+	}
+    }
+
+    if (UNLIKELY(!freelist)) {
+	if (!gc_lazy_sweep(objspace)) {
+	    during_gc = 0;
+	    rb_memerror();
+	}
+    }
+
+    obj = (VALUE)freelist;
+    freelist = freelist->as.free.next;
+
+    MEMZERO((void*)obj, RVALUE, 1);
+#ifdef GC_DEBUG
+    RANY(obj)->file = rb_sourcefile();
+    RANY(obj)->line = rb_sourceline();
+#endif
+    GC_PROF_INC_LIVE_NUM;
+
+    return obj;
+}
+
+NODE*
+rb_node_newnode(enum node_type type, VALUE a0, VALUE a1, VALUE a2)
+{
+    NODE *n = (NODE*)rb_newobj();
+
+    n->flags |= T_NODE;
+    nd_set_type(n, type);
+
+    n->u1.value = a0;
+    n->u2.value = a1;
+    n->u3.value = a2;
+
+    return n;
+}
+
+VALUE
+rb_data_object_alloc(VALUE klass, void *datap, RUBY_DATA_FUNC dmark, RUBY_DATA_FUNC dfree)
+{
+    NEWOBJ(data, struct RData);
+    if (klass) Check_Type(klass, T_CLASS);
+    OBJSETUP(data, klass, T_DATA);
+    data->data = datap;
+    data->dfree = dfree;
+    data->dmark = dmark;
+
+    return (VALUE)data;
+}
+
+VALUE
+rb_data_typed_object_alloc(VALUE klass, void *datap, const rb_data_type_t *type)
+{
+    NEWOBJ(data, struct RTypedData);
+
+    if (klass) Check_Type(klass, T_CLASS);
+
+    OBJSETUP(data, klass, T_DATA);
+
+    data->data = datap;
+    data->typed_flag = 1;
+    data->type = type;
+
+    return (VALUE)data;
+}
+
+size_t
+rb_objspace_data_type_memsize(VALUE obj)
+{
+    if (RTYPEDDATA_P(obj) && RTYPEDDATA_TYPE(obj)->function.dsize) {
+	return RTYPEDDATA_TYPE(obj)->function.dsize(RTYPEDDATA_DATA(obj));
+    }
+    else {
+	return 0;
+    }
+}
+
+const char *
+rb_objspace_data_type_name(VALUE obj)
+{
+    if (RTYPEDDATA_P(obj)) {
+	return RTYPEDDATA_TYPE(obj)->wrap_struct_name;
+    }
+    else {
+	return 0;
+    }
+}
+
+#ifdef __ia64
+#define SET_STACK_END (SET_MACHINE_STACK_END(&th->machine_stack_end), th->machine_register_stack_end = rb_ia64_bsp())
+#else
+#define SET_STACK_END SET_MACHINE_STACK_END(&th->machine_stack_end)
+#endif
+
+#define STACK_START (th->machine_stack_start)
+#define STACK_END (th->machine_stack_end)
+#define STACK_LEVEL_MAX (th->machine_stack_maxsize/sizeof(VALUE))
+
+#if STACK_GROW_DIRECTION < 0
+# define STACK_LENGTH  (size_t)(STACK_START - STACK_END)
+#elif STACK_GROW_DIRECTION > 0
+# define STACK_LENGTH  (size_t)(STACK_END - STACK_START + 1)
+#else
+# define STACK_LENGTH  ((STACK_END < STACK_START) ? (size_t)(STACK_START - STACK_END) \
+			: (size_t)(STACK_END - STACK_START + 1))
+#endif
+#if !STACK_GROW_DIRECTION
+int ruby_stack_grow_direction;
+int
+ruby_get_stack_grow_direction(volatile VALUE *addr)
+{
+    VALUE *end;
+    SET_MACHINE_STACK_END(&end);
+
+    if (end > addr) return ruby_stack_grow_direction = 1;
+    return ruby_stack_grow_direction = -1;
+}
+#endif
+
+#define GC_LEVEL_MAX 250
+#define STACKFRAME_FOR_GC_MARK (GC_LEVEL_MAX * GC_MARK_STACKFRAME_WORD)
+
+size_t
+ruby_stack_length(VALUE **p)
+{
+    rb_thread_t *th = GET_THREAD();
+    SET_STACK_END;
+    if (p) *p = STACK_UPPER(STACK_END, STACK_START, STACK_END);
+    return STACK_LENGTH;
+}
+
+static int
+stack_check(int water_mark)
+{
+    int ret;
+    rb_thread_t *th = GET_THREAD();
+    SET_STACK_END;
+    ret = STACK_LENGTH > STACK_LEVEL_MAX - water_mark;
+#ifdef __ia64
+    if (!ret) {
+        ret = (VALUE*)rb_ia64_bsp() - th->machine_register_stack_start >
+              th->machine_register_stack_maxsize/sizeof(VALUE) - water_mark;
+    }
+#endif
+    return ret;
+}
+
+#define STACKFRAME_FOR_CALL_CFUNC 512
+
+int
+ruby_stack_check(void)
+{
+#if defined(POSIX_SIGNAL) && defined(SIGSEGV) && defined(HAVE_SIGALTSTACK)
+    return 0;
+#else
+    return stack_check(STACKFRAME_FOR_CALL_CFUNC);
+#endif
+}
+
+static void
+init_mark_stack(rb_objspace_t *objspace)
+{
+    mark_stack_overflow = 0;
+    mark_stack_ptr = mark_stack;
+}
+
+#define MARK_STACK_EMPTY (mark_stack_ptr == mark_stack)
+
+static void gc_mark(rb_objspace_t *objspace, VALUE ptr, int lev);
+static void gc_mark_children(rb_objspace_t *objspace, VALUE ptr, int lev);
+
+static void
+gc_mark_all(rb_objspace_t *objspace)
+{
+    RVALUE *p, *pend;
+    size_t i;
+
+    init_mark_stack(objspace);
+    for (i = 0; i < heaps_used; i++) {
+	p = objspace->heap.sorted[i].start; pend = objspace->heap.sorted[i].end;
+	while (p < pend) {
+	    if ((p->as.basic.flags & FL_MARK) &&
+		(p->as.basic.flags != FL_MARK)) {
+		gc_mark_children(objspace, (VALUE)p, 0);
+	    }
+	    p++;
+	}
+    }
+}
+
+static void
+gc_mark_rest(rb_objspace_t *objspace)
+{
+    VALUE tmp_arry[MARK_STACK_MAX];
+    VALUE *p;
+
+    p = (mark_stack_ptr - mark_stack) + tmp_arry;
+    MEMCPY(tmp_arry, mark_stack, VALUE, p - tmp_arry);
+
+    init_mark_stack(objspace);
+    while (p != tmp_arry) {
+	p--;
+	gc_mark_children(objspace, *p, 0);
+    }
+}
+
+static inline int
+is_pointer_to_heap(rb_objspace_t *objspace, void *ptr)
+{
+    register RVALUE *p = RANY(ptr);
+    register struct sorted_heaps_slot *heap;
+    register size_t hi, lo, mid;
+
+    if (p < lomem || p > himem) return FALSE;
+    if ((VALUE)p % sizeof(RVALUE) != 0) return FALSE;
+
+    /* check if p looks like a pointer using bsearch*/
+    lo = 0;
+    hi = heaps_used;
+    while (lo < hi) {
+	mid = (lo + hi) / 2;
+	heap = &objspace->heap.sorted[mid];
+	if (heap->start <= p) {
+	    if (p < heap->end)
+		return TRUE;
+	    lo = mid + 1;
+	}
+	else {
+	    hi = mid;
+	}
+    }
+    return FALSE;
+}
+
+static void
+mark_locations_array(rb_objspace_t *objspace, register VALUE *x, register long n)
+{
+    VALUE v;
+    while (n--) {
+        v = *x;
+        VALGRIND_MAKE_MEM_DEFINED(&v, sizeof(v));
+	if (is_pointer_to_heap(objspace, (void *)v)) {
+	    gc_mark(objspace, v, 0);
+	}
+	x++;
+    }
+}
+
+static void
+gc_mark_locations(rb_objspace_t *objspace, VALUE *start, VALUE *end)
+{
+    long n;
+
+    if (end <= start) return;
+    n = end - start;
+    mark_locations_array(objspace, start, n);
+}
+
+void
+rb_gc_mark_locations(VALUE *start, VALUE *end)
+{
+    gc_mark_locations(&rb_objspace, start, end);
+}
+
+#define rb_gc_mark_locations(start, end) gc_mark_locations(objspace, (start), (end))
+
+struct mark_tbl_arg {
+    rb_objspace_t *objspace;
+    int lev;
+};
+
+static int
+mark_entry(ID key, VALUE value, st_data_t data)
+{
+    struct mark_tbl_arg *arg = (void*)data;
+    gc_mark(arg->objspace, value, arg->lev);
+    return ST_CONTINUE;
+}
+
+static void
+mark_tbl(rb_objspace_t *objspace, st_table *tbl, int lev)
+{
+    struct mark_tbl_arg arg;
+    if (!tbl || tbl->num_entries == 0) return;
+    arg.objspace = objspace;
+    arg.lev = lev;
+    st_foreach(tbl, mark_entry, (st_data_t)&arg);
+}
+
+static int
+mark_key(VALUE key, VALUE value, st_data_t data)
+{
+    struct mark_tbl_arg *arg = (void*)data;
+    gc_mark(arg->objspace, key, arg->lev);
+    return ST_CONTINUE;
+}
+
+static void
+mark_set(rb_objspace_t *objspace, st_table *tbl, int lev)
+{
+    struct mark_tbl_arg arg;
+    if (!tbl) return;
+    arg.objspace = objspace;
+    arg.lev = lev;
+    st_foreach(tbl, mark_key, (st_data_t)&arg);
+}
+
+void
+rb_mark_set(st_table *tbl)
+{
+    mark_set(&rb_objspace, tbl, 0);
+}
+
+static int
+mark_keyvalue(VALUE key, VALUE value, st_data_t data)
+{
+    struct mark_tbl_arg *arg = (void*)data;
+    gc_mark(arg->objspace, key, arg->lev);
+    gc_mark(arg->objspace, value, arg->lev);
+    return ST_CONTINUE;
+}
+
+static void
+mark_hash(rb_objspace_t *objspace, st_table *tbl, int lev)
+{
+    struct mark_tbl_arg arg;
+    if (!tbl) return;
+    arg.objspace = objspace;
+    arg.lev = lev;
+    st_foreach(tbl, mark_keyvalue, (st_data_t)&arg);
+}
+
+void
+rb_mark_hash(st_table *tbl)
+{
+    mark_hash(&rb_objspace, tbl, 0);
+}
+
+static void
+mark_method_entry(rb_objspace_t *objspace, const rb_method_entry_t *me, int lev)
+{
+    const rb_method_definition_t *def = me->def;
+
+    gc_mark(objspace, me->klass, lev);
+    if (!def) return;
+    switch (def->type) {
+      case VM_METHOD_TYPE_ISEQ:
+	gc_mark(objspace, def->body.iseq->self, lev);
+	break;
+      case VM_METHOD_TYPE_BMETHOD:
+	gc_mark(objspace, def->body.proc, lev);
+	break;
+      case VM_METHOD_TYPE_ATTRSET:
+      case VM_METHOD_TYPE_IVAR:
+	gc_mark(objspace, def->body.attr.location, lev);
+	break;
+      default:
+	break; /* ignore */
+    }
+}
+
+void
+rb_mark_method_entry(const rb_method_entry_t *me)
+{
+    mark_method_entry(&rb_objspace, me, 0);
+}
+
+static int
+mark_method_entry_i(ID key, const rb_method_entry_t *me, st_data_t data)
+{
+    struct mark_tbl_arg *arg = (void*)data;
+    mark_method_entry(arg->objspace, me, arg->lev);
+    return ST_CONTINUE;
+}
+
+static void
+mark_m_tbl(rb_objspace_t *objspace, st_table *tbl, int lev)
+{
+    struct mark_tbl_arg arg;
+    if (!tbl) return;
+    arg.objspace = objspace;
+    arg.lev = lev;
+    st_foreach(tbl, mark_method_entry_i, (st_data_t)&arg);
+}
+
+static int
+free_method_entry_i(ID key, rb_method_entry_t *me, st_data_t data)
+{
+    rb_free_method_entry(me);
+    return ST_CONTINUE;
+}
+
+void
+rb_free_m_table(st_table *tbl)
+{
+    st_foreach(tbl, free_method_entry_i, 0);
+    st_free_table(tbl);
+}
+
+static int
+mark_const_entry_i(ID key, const rb_const_entry_t *ce, st_data_t data)
+{
+    struct mark_tbl_arg *arg = (void*)data;
+    gc_mark(arg->objspace, ce->value, arg->lev);
+    return ST_CONTINUE;
+}
+
+static void
+mark_const_tbl(rb_objspace_t *objspace, st_table *tbl, int lev)
+{
+    struct mark_tbl_arg arg;
+    if (!tbl) return;
+    arg.objspace = objspace;
+    arg.lev = lev;
+    st_foreach(tbl, mark_const_entry_i, (st_data_t)&arg);
+}
+
+static int
+free_const_entry_i(ID key, rb_const_entry_t *ce, st_data_t data)
+{
+    xfree(ce);
+    return ST_CONTINUE;
+}
+
+void
+rb_free_const_table(st_table *tbl)
+{
+    st_foreach(tbl, free_const_entry_i, 0);
+    st_free_table(tbl);
+}
+
+void
+rb_mark_tbl(st_table *tbl)
+{
+    mark_tbl(&rb_objspace, tbl, 0);
+}
+
+void
+rb_gc_mark_maybe(VALUE obj)
+{
+    if (is_pointer_to_heap(&rb_objspace, (void *)obj)) {
+	gc_mark(&rb_objspace, obj, 0);
+    }
+}
+
+static void
+gc_mark(rb_objspace_t *objspace, VALUE ptr, int lev)
+{
+    register RVALUE *obj;
+
+    obj = RANY(ptr);
+    if (rb_special_const_p(ptr)) return; /* special const not marked */
+    if (obj->as.basic.flags == 0) return;       /* free cell */
+    if (obj->as.basic.flags & FL_MARK) return;  /* already marked */
+    obj->as.basic.flags |= FL_MARK;
+    objspace->heap.live_num++;
+
+    if (lev > GC_LEVEL_MAX || (lev == 0 && stack_check(STACKFRAME_FOR_GC_MARK))) {
+	if (!mark_stack_overflow) {
+	    if (mark_stack_ptr - mark_stack < MARK_STACK_MAX) {
+		*mark_stack_ptr = ptr;
+		mark_stack_ptr++;
+	    }
+	    else {
+		mark_stack_overflow = 1;
+	    }
+	}
+	return;
+    }
+    gc_mark_children(objspace, ptr, lev+1);
+}
+
+void
+rb_gc_mark(VALUE ptr)
+{
+    gc_mark(&rb_objspace, ptr, 0);
+}
+
+static void
+gc_mark_children(rb_objspace_t *objspace, VALUE ptr, int lev)
+{
+    register RVALUE *obj = RANY(ptr);
+
+    goto marking;		/* skip */
+
+  again:
+    obj = RANY(ptr);
+    if (rb_special_const_p(ptr)) return; /* special const not marked */
+    if (obj->as.basic.flags == 0) return;       /* free cell */
+    if (obj->as.basic.flags & FL_MARK) return;  /* already marked */
+    obj->as.basic.flags |= FL_MARK;
+    objspace->heap.live_num++;
+
+  marking:
+    if (FL_TEST(obj, FL_EXIVAR)) {
+	rb_mark_generic_ivar(ptr);
+    }
+
+    switch (BUILTIN_TYPE(obj)) {
+      case T_NIL:
+      case T_FIXNUM:
+	rb_bug("rb_gc_mark() called for broken object");
+	break;
+
+      case T_NODE:
+	switch (nd_type(obj)) {
+	  case NODE_IF:		/* 1,2,3 */
+	  case NODE_FOR:
+	  case NODE_ITER:
+	  case NODE_WHEN:
+	  case NODE_MASGN:
+	  case NODE_RESCUE:
+	  case NODE_RESBODY:
+	  case NODE_CLASS:
+	  case NODE_BLOCK_PASS:
+	    gc_mark(objspace, (VALUE)obj->as.node.u2.node, lev);
+	    /* fall through */
+	  case NODE_BLOCK:	/* 1,3 */
+	  case NODE_OPTBLOCK:
+	  case NODE_ARRAY:
+	  case NODE_DSTR:
+	  case NODE_DXSTR:
+	  case NODE_DREGX:
+	  case NODE_DREGX_ONCE:
+	  case NODE_ENSURE:
+	  case NODE_CALL:
+	  case NODE_DEFS:
+	  case NODE_OP_ASGN1:
+	  case NODE_ARGS:
+	    gc_mark(objspace, (VALUE)obj->as.node.u1.node, lev);
+	    /* fall through */
+	  case NODE_SUPER:	/* 3 */
+	  case NODE_FCALL:
+	  case NODE_DEFN:
+	  case NODE_ARGS_AUX:
+	    ptr = (VALUE)obj->as.node.u3.node;
+	    goto again;
+
+	  case NODE_WHILE:	/* 1,2 */
+	  case NODE_UNTIL:
+	  case NODE_AND:
+	  case NODE_OR:
+	  case NODE_CASE:
+	  case NODE_SCLASS:
+	  case NODE_DOT2:
+	  case NODE_DOT3:
+	  case NODE_FLIP2:
+	  case NODE_FLIP3:
+	  case NODE_MATCH2:
+	  case NODE_MATCH3:
+	  case NODE_OP_ASGN_OR:
+	  case NODE_OP_ASGN_AND:
+	  case NODE_MODULE:
+	  case NODE_ALIAS:
+	  case NODE_VALIAS:
+	  case NODE_ARGSCAT:
+	    gc_mark(objspace, (VALUE)obj->as.node.u1.node, lev);
+	    /* fall through */
+	  case NODE_GASGN:	/* 2 */
+	  case NODE_LASGN:
+	  case NODE_DASGN:
+	  case NODE_DASGN_CURR:
+	  case NODE_IASGN:
+	  case NODE_IASGN2:
+	  case NODE_CVASGN:
+	  case NODE_COLON3:
+	  case NODE_OPT_N:
+	  case NODE_EVSTR:
+	  case NODE_UNDEF:
+	  case NODE_POSTEXE:
+	    ptr = (VALUE)obj->as.node.u2.node;
+	    goto again;
+
+	  case NODE_HASH:	/* 1 */
+	  case NODE_LIT:
+	  case NODE_STR:
+	  case NODE_XSTR:
+	  case NODE_DEFINED:
+	  case NODE_MATCH:
+	  case NODE_RETURN:
+	  case NODE_BREAK:
+	  case NODE_NEXT:
+	  case NODE_YIELD:
+	  case NODE_COLON2:
+	  case NODE_SPLAT:
+	  case NODE_TO_ARY:
+	    ptr = (VALUE)obj->as.node.u1.node;
+	    goto again;
+
+	  case NODE_SCOPE:	/* 2,3 */
+	  case NODE_CDECL:
+	  case NODE_OPT_ARG:
+	    gc_mark(objspace, (VALUE)obj->as.node.u3.node, lev);
+	    ptr = (VALUE)obj->as.node.u2.node;
+	    goto again;
+
+	  case NODE_ZARRAY:	/* - */
+	  case NODE_ZSUPER:
+	  case NODE_VCALL:
+	  case NODE_GVAR:
+	  case NODE_LVAR:
+	  case NODE_DVAR:
+	  case NODE_IVAR:
+	  case NODE_CVAR:
+	  case NODE_NTH_REF:
+	  case NODE_BACK_REF:
+	  case NODE_REDO:
+	  case NODE_RETRY:
+	  case NODE_SELF:
+	  case NODE_NIL:
+	  case NODE_TRUE:
+	  case NODE_FALSE:
+	  case NODE_ERRINFO:
+	  case NODE_BLOCK_ARG:
+	    break;
+	  case NODE_ALLOCA:
+	    mark_locations_array(objspace,
+				 (VALUE*)obj->as.node.u1.value,
+				 obj->as.node.u3.cnt);
+	    ptr = (VALUE)obj->as.node.u2.node;
+	    goto again;
+
+	  default:		/* unlisted NODE */
+	    if (is_pointer_to_heap(objspace, obj->as.node.u1.node)) {
+		gc_mark(objspace, (VALUE)obj->as.node.u1.node, lev);
+	    }
+	    if (is_pointer_to_heap(objspace, obj->as.node.u2.node)) {
+		gc_mark(objspace, (VALUE)obj->as.node.u2.node, lev);
+	    }
+	    if (is_pointer_to_heap(objspace, obj->as.node.u3.node)) {
+		gc_mark(objspace, (VALUE)obj->as.node.u3.node, lev);
+	    }
+	}
+	return;			/* no need to mark class. */
+    }
+
+    gc_mark(objspace, obj->as.basic.klass, lev);
+    switch (BUILTIN_TYPE(obj)) {
+      case T_ICLASS:
+      case T_CLASS:
+      case T_MODULE:
+	mark_m_tbl(objspace, RCLASS_M_TBL(obj), lev);
+	mark_tbl(objspace, RCLASS_IV_TBL(obj), lev);
+	mark_const_tbl(objspace, RCLASS_CONST_TBL(obj), lev);
+	ptr = RCLASS_SUPER(obj);
+	goto again;
+
+      case T_ARRAY:
+	if (FL_TEST(obj, ELTS_SHARED)) {
+	    ptr = obj->as.array.as.heap.aux.shared;
+	    goto again;
+	}
+	else {
+	    long i, len = RARRAY_LEN(obj);
+	    VALUE *ptr = RARRAY_PTR(obj);
+	    for (i=0; i < len; i++) {
+		gc_mark(objspace, *ptr++, lev);
+	    }
+	}
+	break;
+
+      case T_HASH:
+	mark_hash(objspace, obj->as.hash.ntbl, lev);
+	ptr = obj->as.hash.ifnone;
+	goto again;
+
+      case T_STRING:
+#define STR_ASSOC FL_USER3   /* copied from string.c */
+	if (FL_TEST(obj, RSTRING_NOEMBED) && FL_ANY(obj, ELTS_SHARED|STR_ASSOC)) {
+	    ptr = obj->as.string.as.heap.aux.shared;
+	    goto again;
+	}
+	break;
+
+      case T_DATA:
+	if (RTYPEDDATA_P(obj)) {
+	    RUBY_DATA_FUNC mark_func = obj->as.typeddata.type->function.dmark;
+	    if (mark_func) (*mark_func)(DATA_PTR(obj));
+	}
+	else {
+	    if (obj->as.data.dmark) (*obj->as.data.dmark)(DATA_PTR(obj));
+	}
+	break;
+
+      case T_OBJECT:
+        {
+            long i, len = ROBJECT_NUMIV(obj);
+	    VALUE *ptr = ROBJECT_IVPTR(obj);
+            for (i  = 0; i < len; i++) {
+		gc_mark(objspace, *ptr++, lev);
+            }
+        }
+	break;
+
+      case T_FILE:
+        if (obj->as.file.fptr) {
+            gc_mark(objspace, obj->as.file.fptr->pathv, lev);
+            gc_mark(objspace, obj->as.file.fptr->tied_io_for_writing, lev);
+            gc_mark(objspace, obj->as.file.fptr->writeconv_asciicompat, lev);
+            gc_mark(objspace, obj->as.file.fptr->writeconv_pre_ecopts, lev);
+            gc_mark(objspace, obj->as.file.fptr->encs.ecopts, lev);
+            gc_mark(objspace, obj->as.file.fptr->write_lock, lev);
+        }
+        break;
+
+      case T_REGEXP:
+        gc_mark(objspace, obj->as.regexp.src, lev);
+        break;
+
+      case T_FLOAT:
+      case T_BIGNUM:
+      case T_ZOMBIE:
+	break;
+
+      case T_MATCH:
+	gc_mark(objspace, obj->as.match.regexp, lev);
+	if (obj->as.match.str) {
+	    ptr = obj->as.match.str;
+	    goto again;
+	}
+	break;
+
+      case T_RATIONAL:
+	gc_mark(objspace, obj->as.rational.num, lev);
+	gc_mark(objspace, obj->as.rational.den, lev);
+	break;
+
+      case T_COMPLEX:
+	gc_mark(objspace, obj->as.complex.real, lev);
+	gc_mark(objspace, obj->as.complex.imag, lev);
+	break;
+
+      case T_STRUCT:
+	{
+	    long len = RSTRUCT_LEN(obj);
+	    VALUE *ptr = RSTRUCT_PTR(obj);
+
+	    while (len--) {
+		gc_mark(objspace, *ptr++, lev);
+	    }
+	}
+	break;
+
+      default:
+	rb_bug("rb_gc_mark(): unknown data type 0x%x(%p) %s",
+	       BUILTIN_TYPE(obj), (void *)obj,
+	       is_pointer_to_heap(objspace, obj) ? "corrupted object" : "non object");
+    }
+}
+
+static int obj_free(rb_objspace_t *, VALUE);
+
+static inline void
+add_freelist(rb_objspace_t *objspace, RVALUE *p)
+{
+    VALGRIND_MAKE_MEM_UNDEFINED((void*)p, sizeof(RVALUE));
+    p->as.free.flags = 0;
+    p->as.free.next = freelist;
+    freelist = p;
+}
+
+static void
+finalize_list(rb_objspace_t *objspace, RVALUE *p)
+{
+    while (p) {
+	RVALUE *tmp = p->as.free.next;
+	run_final(objspace, (VALUE)p);
+	if (!FL_TEST(p, FL_SINGLETON)) { /* not freeing page */
+            if (objspace->heap.sweep_slots) {
+                p->as.free.flags = 0;
+            }
+            else {
+                GC_PROF_DEC_LIVE_NUM;
+                add_freelist(objspace, p);
+            }
+	}
+	else {
+	    struct heaps_slot *slot = (struct heaps_slot *)(VALUE)RDATA(p)->dmark;
+	    slot->limit--;
+	}
+	p = tmp;
+    }
+}
+
+static void
+unlink_heap_slot(rb_objspace_t *objspace, struct heaps_slot *slot)
+{
+    if (slot->prev)
+        slot->prev->next = slot->next;
+    if (slot->next)
+        slot->next->prev = slot->prev;
+    if (heaps == slot)
+        heaps = slot->next;
+    if (objspace->heap.sweep_slots == slot)
+        objspace->heap.sweep_slots = slot->next;
+    slot->prev = NULL;
+    slot->next = NULL;
+}
+
+
+static void
+free_unused_heaps(rb_objspace_t *objspace)
+{
+    size_t i, j;
+    RVALUE *last = 0;
+
+    for (i = j = 1; j < heaps_used; i++) {
+	if (objspace->heap.sorted[i].slot->limit == 0) {
+	    if (!last) {
+		last = objspace->heap.sorted[i].slot->membase;
+	    }
+	    else {
+		free(objspace->heap.sorted[i].slot->membase);
+	    }
+            free(objspace->heap.sorted[i].slot);
+	    heaps_used--;
+	}
+	else {
+	    if (i != j) {
+		objspace->heap.sorted[j] = objspace->heap.sorted[i];
+	    }
+	    j++;
+	}
+    }
+    if (last) {
+	if (last < heaps_freed) {
+	    free(heaps_freed);
+	    heaps_freed = last;
+	}
+	else {
+	    free(last);
+	}
+    }
+}
+
+static void
+slot_sweep(rb_objspace_t *objspace, struct heaps_slot *sweep_slot)
+{
+    size_t free_num = 0, final_num = 0;
+    RVALUE *p, *pend;
+    RVALUE *free = freelist, *final = deferred_final_list;
+    int deferred;
+
+    p = sweep_slot->slot; pend = p + sweep_slot->limit;
+    while (p < pend) {
+        if (!(p->as.basic.flags & FL_MARK)) {
+            if (p->as.basic.flags &&
+                ((deferred = obj_free(objspace, (VALUE)p)) ||
+		 (FL_TEST(p, FL_FINALIZE)))) {
+                if (!deferred) {
+                    p->as.free.flags = T_ZOMBIE;
+                    RDATA(p)->dfree = 0;
+                }
+                p->as.free.flags |= FL_MARK;
+                p->as.free.next = deferred_final_list;
+                deferred_final_list = p;
+                final_num++;
+            }
+            else {
+                add_freelist(objspace, p);
+                free_num++;
+            }
+        }
+        else if (BUILTIN_TYPE(p) == T_ZOMBIE) {
+            /* objects to be finalized */
+            /* do nothing remain marked */
+        }
+        else {
+            RBASIC(p)->flags &= ~FL_MARK;
+        }
+        p++;
+    }
+    if (final_num + free_num == sweep_slot->limit &&
+        objspace->heap.free_num > objspace->heap.do_heap_free) {
+        RVALUE *pp;
+
+        for (pp = deferred_final_list; pp != final; pp = pp->as.free.next) {
+	    RDATA(pp)->dmark = (void (*)(void *))(VALUE)sweep_slot;
+            pp->as.free.flags |= FL_SINGLETON; /* freeing page mark */
+        }
+        sweep_slot->limit = final_num;
+        freelist = free;	/* cancel this page from freelist */
+        unlink_heap_slot(objspace, sweep_slot);
+    }
+    else {
+        objspace->heap.free_num += free_num;
+    }
+    objspace->heap.final_num += final_num;
+
+    if (deferred_final_list) {
+        rb_thread_t *th = GET_THREAD();
+        if (th) {
+            RUBY_VM_SET_FINALIZER_INTERRUPT(th);
+        }
+    }
+}
+
+static int
+ready_to_gc(rb_objspace_t *objspace)
+{
+    if (dont_gc || during_gc) {
+	if (!freelist) {
+            if (!heaps_increment(objspace)) {
+                set_heaps_increment(objspace);
+                heaps_increment(objspace);
+            }
+	}
+	return FALSE;
+    }
+    return TRUE;
+}
+
+static void
+before_gc_sweep(rb_objspace_t *objspace)
+{
+    freelist = 0;
+    objspace->heap.do_heap_free = (size_t)((heaps_used * HEAP_OBJ_LIMIT) * 0.65);
+    objspace->heap.free_min = (size_t)((heaps_used * HEAP_OBJ_LIMIT)  * 0.2);
+    if (objspace->heap.free_min < initial_free_min) {
+	objspace->heap.do_heap_free = heaps_used * HEAP_OBJ_LIMIT;
+        objspace->heap.free_min = initial_free_min;
+    }
+    objspace->heap.sweep_slots = heaps;
+    objspace->heap.free_num = 0;
+
+    /* sweep unlinked method entries */
+    if (GET_VM()->unlinked_method_entry_list) {
+	rb_sweep_method_entry(GET_VM());
+    }
+}
+
+static void
+after_gc_sweep(rb_objspace_t *objspace)
+{
+    GC_PROF_SET_MALLOC_INFO;
+
+    if (objspace->heap.free_num < objspace->heap.free_min) {
+        set_heaps_increment(objspace);
+        heaps_increment(objspace);
+    }
+
+    if (malloc_increase > malloc_limit) {
+	malloc_limit += (size_t)((malloc_increase - malloc_limit) * (double)objspace->heap.live_num / (heaps_used * HEAP_OBJ_LIMIT));
+	if (malloc_limit < initial_malloc_limit) malloc_limit = initial_malloc_limit;
+    }
+    malloc_increase = 0;
+
+    free_unused_heaps(objspace);
+}
+
+static int
+lazy_sweep(rb_objspace_t *objspace)
+{
+    struct heaps_slot *next;
+
+    heaps_increment(objspace);
+    while (objspace->heap.sweep_slots) {
+        next = objspace->heap.sweep_slots->next;
+	slot_sweep(objspace, objspace->heap.sweep_slots);
+        objspace->heap.sweep_slots = next;
+        if (freelist) {
+            during_gc = 0;
+            return TRUE;
+        }
+    }
+    return FALSE;
+}
+
+static void
+rest_sweep(rb_objspace_t *objspace)
+{
+    if (objspace->heap.sweep_slots) {
+       while (objspace->heap.sweep_slots) {
+           lazy_sweep(objspace);
+       }
+       after_gc_sweep(objspace);
+    }
+}
+
+static void gc_marks(rb_objspace_t *objspace);
+
+static int
+gc_lazy_sweep(rb_objspace_t *objspace)
+{
+    int res;
+    INIT_GC_PROF_PARAMS;
+
+    if (objspace->flags.dont_lazy_sweep)
+        return garbage_collect(objspace);
+
+
+    if (!ready_to_gc(objspace)) return TRUE;
+
+    during_gc++;
+    GC_PROF_TIMER_START;
+    GC_PROF_SWEEP_TIMER_START;
+
+    if (objspace->heap.sweep_slots) {
+        res = lazy_sweep(objspace);
+        if (res) {
+            GC_PROF_SWEEP_TIMER_STOP;
+            GC_PROF_SET_MALLOC_INFO;
+            GC_PROF_TIMER_STOP(Qfalse);
+            return res;
+        }
+        after_gc_sweep(objspace);
+    }
+    else {
+        if (heaps_increment(objspace)) {
+            during_gc = 0;
+            return TRUE;
+        }
+    }
+
+    gc_marks(objspace);
+
+    before_gc_sweep(objspace);
+    if (objspace->heap.free_min > (heaps_used * HEAP_OBJ_LIMIT - objspace->heap.live_num)) {
+	set_heaps_increment(objspace);
+    }
+
+    GC_PROF_SWEEP_TIMER_START;
+    if(!(res = lazy_sweep(objspace))) {
+        after_gc_sweep(objspace);
+        if(freelist) {
+            res = TRUE;
+            during_gc = 0;
+        }
+    }
+    GC_PROF_SWEEP_TIMER_STOP;
+
+    GC_PROF_TIMER_STOP(Qtrue);
+    return res;
+}
+
+static void
+gc_sweep(rb_objspace_t *objspace)
+{
+    struct heaps_slot *next;
+
+    before_gc_sweep(objspace);
+
+    while (objspace->heap.sweep_slots) {
+        next = objspace->heap.sweep_slots->next;
+	slot_sweep(objspace, objspace->heap.sweep_slots);
+        objspace->heap.sweep_slots = next;
+    }
+
+    after_gc_sweep(objspace);
+
+    during_gc = 0;
+}
+
+void
+rb_gc_force_recycle(VALUE p)
+{
+    rb_objspace_t *objspace = &rb_objspace;
+    GC_PROF_DEC_LIVE_NUM;
+    if (RBASIC(p)->flags & FL_MARK) {
+        RANY(p)->as.free.flags = 0;
+    }
+    else {
+        add_freelist(objspace, (RVALUE *)p);
+    }
+}
+
+static inline void
+make_deferred(RVALUE *p)
+{
+    p->as.basic.flags = (p->as.basic.flags & ~T_MASK) | T_ZOMBIE;
+}
+
+static inline void
+make_io_deferred(RVALUE *p)
+{
+    rb_io_t *fptr = p->as.file.fptr;
+    make_deferred(p);
+    p->as.data.dfree = (void (*)(void*))rb_io_fptr_finalize;
+    p->as.data.data = fptr;
+}
+
+static int
+obj_free(rb_objspace_t *objspace, VALUE obj)
+{
+    switch (BUILTIN_TYPE(obj)) {
+      case T_NIL:
+      case T_FIXNUM:
+      case T_TRUE:
+      case T_FALSE:
+	rb_bug("obj_free() called for broken object");
+	break;
+    }
+
+    if (FL_TEST(obj, FL_EXIVAR)) {
+	rb_free_generic_ivar((VALUE)obj);
+	FL_UNSET(obj, FL_EXIVAR);
+    }
+
+    switch (BUILTIN_TYPE(obj)) {
+      case T_OBJECT:
+	if (!(RANY(obj)->as.basic.flags & ROBJECT_EMBED) &&
+            RANY(obj)->as.object.as.heap.ivptr) {
+	    xfree(RANY(obj)->as.object.as.heap.ivptr);
+	}
+	break;
+      case T_MODULE:
+      case T_CLASS:
+	rb_clear_cache_by_class((VALUE)obj);
+	rb_free_m_table(RCLASS_M_TBL(obj));
+	if (RCLASS_IV_TBL(obj)) {
+	    st_free_table(RCLASS_IV_TBL(obj));
+	}
+	if (RCLASS_CONST_TBL(obj)) {
+	    rb_free_const_table(RCLASS_CONST_TBL(obj));
+	}
+	if (RCLASS_IV_INDEX_TBL(obj)) {
+	    st_free_table(RCLASS_IV_INDEX_TBL(obj));
+	}
+        xfree(RANY(obj)->as.klass.ptr);
+	break;
+      case T_STRING:
+	rb_str_free(obj);
+	break;
+      case T_ARRAY:
+	rb_ary_free(obj);
+	break;
+      case T_HASH:
+	if (RANY(obj)->as.hash.ntbl) {
+	    st_free_table(RANY(obj)->as.hash.ntbl);
+	}
+	break;
+      case T_REGEXP:
+	if (RANY(obj)->as.regexp.ptr) {
+	    onig_free(RANY(obj)->as.regexp.ptr);
+	}
+	break;
+      case T_DATA:
+	if (DATA_PTR(obj)) {
+	    if (RTYPEDDATA_P(obj)) {
+		RDATA(obj)->dfree = RANY(obj)->as.typeddata.type->function.dfree;
+	    }
+	    if (RANY(obj)->as.data.dfree == (RUBY_DATA_FUNC)-1) {
+		xfree(DATA_PTR(obj));
+	    }
+	    else if (RANY(obj)->as.data.dfree) {
+		make_deferred(RANY(obj));
+		return 1;
+	    }
+	}
+	break;
+      case T_MATCH:
+	if (RANY(obj)->as.match.rmatch) {
+            struct rmatch *rm = RANY(obj)->as.match.rmatch;
+	    onig_region_free(&rm->regs, 0);
+            if (rm->char_offset)
+		xfree(rm->char_offset);
+	    xfree(rm);
+	}
+	break;
+      case T_FILE:
+	if (RANY(obj)->as.file.fptr) {
+	    make_io_deferred(RANY(obj));
+	    return 1;
+	}
+	break;
+      case T_RATIONAL:
+      case T_COMPLEX:
+	break;
+      case T_ICLASS:
+	/* iClass shares table with the module */
+	xfree(RANY(obj)->as.klass.ptr);
+	break;
+
+      case T_FLOAT:
+	break;
+
+      case T_BIGNUM:
+	if (!(RBASIC(obj)->flags & RBIGNUM_EMBED_FLAG) && RBIGNUM_DIGITS(obj)) {
+	    xfree(RBIGNUM_DIGITS(obj));
+	}
+	break;
+      case T_NODE:
+	switch (nd_type(obj)) {
+	  case NODE_SCOPE:
+	    if (RANY(obj)->as.node.u1.tbl) {
+		xfree(RANY(obj)->as.node.u1.tbl);
+	    }
+	    break;
+	  case NODE_ALLOCA:
+	    xfree(RANY(obj)->as.node.u1.node);
+	    break;
+	}
+	break;			/* no need to free iv_tbl */
+
+      case T_STRUCT:
+	if ((RBASIC(obj)->flags & RSTRUCT_EMBED_LEN_MASK) == 0 &&
+	    RANY(obj)->as.rstruct.as.heap.ptr) {
+	    xfree(RANY(obj)->as.rstruct.as.heap.ptr);
+	}
+	break;
+
+      default:
+	rb_bug("gc_sweep(): unknown data type 0x%x(%p)",
+	       BUILTIN_TYPE(obj), (void*)obj);
+    }
+
+    return 0;
+}
+
+#define GC_NOTIFY 0
+
+#if STACK_GROW_DIRECTION < 0
+#define GET_STACK_BOUNDS(start, end, appendix) ((start) = STACK_END, (end) = STACK_START)
+#elif STACK_GROW_DIRECTION > 0
+#define GET_STACK_BOUNDS(start, end, appendix) ((start) = STACK_START, (end) = STACK_END+(appendix))
+#else
+#define GET_STACK_BOUNDS(start, end, appendix) \
+    ((STACK_END < STACK_START) ? \
+     ((start) = STACK_END, (end) = STACK_START) : ((start) = STACK_START, (end) = STACK_END+(appendix)))
+#endif
+
+#define numberof(array) (int)(sizeof(array) / sizeof((array)[0]))
+
+static void
+mark_current_machine_context(rb_objspace_t *objspace, rb_thread_t *th)
+{
+    union {
+	rb_jmp_buf j;
+	VALUE v[sizeof(rb_jmp_buf) / sizeof(VALUE)];
+    } save_regs_gc_mark;
+    VALUE *stack_start, *stack_end;
+
+    FLUSH_REGISTER_WINDOWS;
+    /* This assumes that all registers are saved into the jmp_buf (and stack) */
+    rb_setjmp(save_regs_gc_mark.j);
+
+    SET_STACK_END;
+    GET_STACK_BOUNDS(stack_start, stack_end, 1);
+
+    mark_locations_array(objspace, save_regs_gc_mark.v, numberof(save_regs_gc_mark.v));
+
+    rb_gc_mark_locations(stack_start, stack_end);
+#ifdef __ia64
+    rb_gc_mark_locations(th->machine_register_stack_start, th->machine_register_stack_end);
+#endif
+#if defined(__mc68000__)
+    mark_locations_array(objspace, (VALUE*)((char*)STACK_END + 2),
+			 (STACK_START - STACK_END));
+#endif
+}
+
+static void
+gc_marks(rb_objspace_t *objspace)
+{
+    struct gc_list *list;
+    rb_thread_t *th = GET_THREAD();
+    GC_PROF_MARK_TIMER_START;
+
+    objspace->heap.live_num = 0;
+    objspace->count++;
+
+
+    SET_STACK_END;
+
+    init_mark_stack(objspace);
+
+    th->vm->self ? rb_gc_mark(th->vm->self) : rb_vm_mark(th->vm);
+
+    mark_tbl(objspace, finalizer_table, 0);
+    mark_current_machine_context(objspace, th);
+
+    rb_gc_mark_symbols();
+    rb_gc_mark_encodings();
+
+    /* mark protected global variables */
+    for (list = global_List; list; list = list->next) {
+	rb_gc_mark_maybe(*list->varptr);
+    }
+    rb_mark_end_proc();
+    rb_gc_mark_global_tbl();
+
+    mark_tbl(objspace, rb_class_tbl, 0);
+
+    /* mark generic instance variables for special constants */
+    rb_mark_generic_ivar_tbl();
+
+    rb_gc_mark_parser();
+
+    rb_gc_mark_unlinked_live_method_entries(th->vm);
+
+    /* gc_mark objects whose marking are not completed*/
+    while (!MARK_STACK_EMPTY) {
+	if (mark_stack_overflow) {
+	    gc_mark_all(objspace);
+	}
+	else {
+	    gc_mark_rest(objspace);
+	}
+    }
+    GC_PROF_MARK_TIMER_STOP;
+}
+
+static int
+garbage_collect(rb_objspace_t *objspace)
+{
+    INIT_GC_PROF_PARAMS;
+
+    if (GC_NOTIFY) printf("start garbage_collect()\n");
+
+    if (!heaps) {
+	return FALSE;
+    }
+    if (!ready_to_gc(objspace)) {
+        return TRUE;
+    }
+
+    GC_PROF_TIMER_START;
+
+    rest_sweep(objspace);
+
+    during_gc++;
+    gc_marks(objspace);
+
+    GC_PROF_SWEEP_TIMER_START;
+    gc_sweep(objspace);
+    GC_PROF_SWEEP_TIMER_STOP;
+
+    GC_PROF_TIMER_STOP(Qtrue);
+    if (GC_NOTIFY) printf("end garbage_collect()\n");
+    return TRUE;
+}
+
+int
+rb_garbage_collect(void)
+{
+    return garbage_collect(&rb_objspace);
+}
+
+void
+rb_gc_mark_machine_stack(rb_thread_t *th)
+{
+    rb_objspace_t *objspace = &rb_objspace;
+    VALUE *stack_start, *stack_end;
+
+    GET_STACK_BOUNDS(stack_start, stack_end, 0);
+    rb_gc_mark_locations(stack_start, stack_end);
+#ifdef __ia64
+    rb_gc_mark_locations(th->machine_register_stack_start, th->machine_register_stack_end);
+#endif
+}
+
+
+/*
+ *  call-seq:
+ *     GC.start                     -> nil
+ *     gc.garbage_collect           -> nil
+ *     ObjectSpace.garbage_collect  -> nil
+ *
+ *  Initiates garbage collection, unless manually disabled.
+ *
+ */
+
+VALUE
+rb_gc_start(void)
+{
+    rb_gc();
+    return Qnil;
+}
+
+#undef Init_stack
+
+void
+Init_stack(volatile VALUE *addr)
+{
+    ruby_init_stack(addr);
+}
+
+/*
+ * Document-class: ObjectSpace
+ *
+ *  The <code>ObjectSpace</code> module contains a number of routines
+ *  that interact with the garbage collection facility and allow you to
+ *  traverse all living objects with an iterator.
+ *
+ *  <code>ObjectSpace</code> also provides support for object
+ *  finalizers, procs that will be called when a specific object is
+ *  about to be destroyed by garbage collection.
+ *
+ *     include ObjectSpace
+ *
+ *
+ *     a = "A"
+ *     b = "B"
+ *     c = "C"
+ *
+ *
+ *     define_finalizer(a, proc {|id| puts "Finalizer one on #{id}" })
+ *     define_finalizer(a, proc {|id| puts "Finalizer two on #{id}" })
+ *     define_finalizer(b, proc {|id| puts "Finalizer three on #{id}" })
+ *
+ *  <em>produces:</em>
+ *
+ *     Finalizer three on 537763470
+ *     Finalizer one on 537763480
+ *     Finalizer two on 537763480
+ *
+ */
+
+void
+Init_heap(void)
+{
+    init_heap(&rb_objspace);
+}
+
+static VALUE
+lazy_sweep_enable(void)
+{
+    rb_objspace_t *objspace = &rb_objspace;
+
+    objspace->flags.dont_lazy_sweep = FALSE;
+    return Qnil;
+}
+
+typedef int each_obj_callback(void *, void *, size_t, void *);
+
+struct each_obj_args {
+    each_obj_callback *callback;
+    void *data;
+};
+
+static VALUE
+objspace_each_objects(VALUE arg)
+{
+    size_t i;
+    RVALUE *membase = 0;
+    RVALUE *pstart, *pend;
+    rb_objspace_t *objspace = &rb_objspace;
+    struct each_obj_args *args = (struct each_obj_args *)arg;
+    volatile VALUE v;
+
+    i = 0;
+    while (i < heaps_used) {
+	while (0 < i && (uintptr_t)membase < (uintptr_t)objspace->heap.sorted[i-1].slot->membase)
+	    i--;
+	while (i < heaps_used && (uintptr_t)objspace->heap.sorted[i].slot->membase <= (uintptr_t)membase)
+	    i++;
+	if (heaps_used <= i)
+	  break;
+	membase = objspace->heap.sorted[i].slot->membase;
+
+	pstart = objspace->heap.sorted[i].slot->slot;
+	pend = pstart + objspace->heap.sorted[i].slot->limit;
+
+	for (; pstart != pend; pstart++) {
+	    if (pstart->as.basic.flags) {
+		v = (VALUE)pstart; /* acquire to save this object */
+		break;
+	    }
+	}
+	if (pstart != pend) {
+	    if ((*args->callback)(pstart, pend, sizeof(RVALUE), args->data)) {
+		break;
+	    }
+	}
+    }
+
+    return Qnil;
+}
+
+/*
+ * rb_objspace_each_objects() is special C API to walk through
+ * Ruby object space.  This C API is too difficult to use it.
+ * To be frank, you should not use it. Or you need to read the
+ * source code of this function and understand what this function does.
+ *
+ * 'callback' will be called several times (the number of heap slot,
+ * at current implementation) with:
+ *   vstart: a pointer to the first living object of the heap_slot.
+ *   vend: a pointer to next to the valid heap_slot area.
+ *   stride: a distance to next VALUE.
+ *
+ * If callback() returns non-zero, the iteration will be stopped.
+ *
+ * This is a sample callback code to iterate liveness objects:
+ *
+ *   int
+ *   sample_callback(void *vstart, void *vend, int stride, void *data) {
+ *     VALUE v = (VALUE)vstart;
+ *     for (; v != (VALUE)vend; v += stride) {
+ *       if (RBASIC(v)->flags) { // liveness check
+ *       // do something with live object 'v'
+ *     }
+ *     return 0; // continue to iteration
+ *   }
+ *
+ * Note: 'vstart' is not a top of heap_slot.  This point the first
+ *       living object to grasp at least one object to avoid GC issue.
+ *       This means that you can not walk through all Ruby object slot
+ *       including freed object slot.
+ *
+ * Note: On this implementation, 'stride' is same as sizeof(RVALUE).
+ *       However, there are possibilities to pass variable values with
+ *       'stride' with some reasons.  You must use stride instead of
+ *       use some constant value in the iteration.
+ */
+void
+rb_objspace_each_objects(each_obj_callback *callback, void *data)
+{
+    struct each_obj_args args;
+    rb_objspace_t *objspace = &rb_objspace;
+
+    rest_sweep(objspace);
+    objspace->flags.dont_lazy_sweep = TRUE;
+
+    args.callback = callback;
+    args.data = data;
+    rb_ensure(objspace_each_objects, (VALUE)&args, lazy_sweep_enable, Qnil);
+}
+
+struct os_each_struct {
+    size_t num;
+    VALUE of;
+};
+
+static int
+os_obj_of_i(void *vstart, void *vend, size_t stride, void *data)
+{
+    struct os_each_struct *oes = (struct os_each_struct *)data;
+    RVALUE *p = (RVALUE *)vstart, *pend = (RVALUE *)vend;
+    volatile VALUE v;
+
+    for (; p != pend; p++) {
+	if (p->as.basic.flags) {
+	    switch (BUILTIN_TYPE(p)) {
+	      case T_NONE:
+	      case T_ICLASS:
+	      case T_NODE:
+	      case T_ZOMBIE:
+		continue;
+	      case T_CLASS:
+		if (FL_TEST(p, FL_SINGLETON))
+		  continue;
+	      default:
+		if (!p->as.basic.klass) continue;
+		v = (VALUE)p;
+		if (!oes->of || rb_obj_is_kind_of(v, oes->of)) {
+		    rb_yield(v);
+		    oes->num++;
+		}
+	    }
+	}
+    }
+
+    return 0;
+}
+
+static VALUE
+os_obj_of(VALUE of)
+{
+    struct os_each_struct oes;
+
+    oes.num = 0;
+    oes.of = of;
+    rb_objspace_each_objects(os_obj_of_i, &oes);
+    return SIZET2NUM(oes.num);
+}
+
+/*
+ *  call-seq:
+ *     ObjectSpace.each_object([module]) {|obj| ... } -> fixnum
+ *     ObjectSpace.each_object([module])              -> an_enumerator
+ *
+ *  Calls the block once for each living, nonimmediate object in this
+ *  Ruby process. If <i>module</i> is specified, calls the block
+ *  for only those classes or modules that match (or are a subclass of)
+ *  <i>module</i>. Returns the number of objects found. Immediate
+ *  objects (<code>Fixnum</code>s, <code>Symbol</code>s
+ *  <code>true</code>, <code>false</code>, and <code>nil</code>) are
+ *  never returned. In the example below, <code>each_object</code>
+ *  returns both the numbers we defined and several constants defined in
+ *  the <code>Math</code> module.
+ *
+ *  If no block is given, an enumerator is returned instead.
+ *
+ *     a = 102.7
+ *     b = 95       # Won't be returned
+ *     c = 12345678987654321
+ *     count = ObjectSpace.each_object(Numeric) {|x| p x }
+ *     puts "Total count: #{count}"
+ *
+ *  <em>produces:</em>
+ *
+ *     12345678987654321
+ *     102.7
+ *     2.71828182845905
+ *     3.14159265358979
+ *     2.22044604925031e-16
+ *     1.7976931348623157e+308
+ *     2.2250738585072e-308
+ *     Total count: 7
+ *
+ */
+
+static VALUE
+os_each_obj(int argc, VALUE *argv, VALUE os)
+{
+    VALUE of;
+
+    rb_secure(4);
+    if (argc == 0) {
+	of = 0;
+    }
+    else {
+	rb_scan_args(argc, argv, "01", &of);
+    }
+    RETURN_ENUMERATOR(os, 1, &of);
+    return os_obj_of(of);
+}
+
+/*
+ *  call-seq:
+ *     ObjectSpace.undefine_finalizer(obj)
+ *
+ *  Removes all finalizers for <i>obj</i>.
+ *
+ */
+
+static VALUE
+undefine_final(VALUE os, VALUE obj)
+{
+    rb_objspace_t *objspace = &rb_objspace;
+    st_data_t data = obj;
+    rb_check_frozen(obj);
+    st_delete(finalizer_table, &data, 0);
+    FL_UNSET(obj, FL_FINALIZE);
+    return obj;
+}
+
+/*
+ *  call-seq:
+ *     ObjectSpace.define_finalizer(obj, aProc=proc())
+ *
+ *  Adds <i>aProc</i> as a finalizer, to be called after <i>obj</i>
+ *  was destroyed.
+ *
+ */
+
+static VALUE
+define_final(int argc, VALUE *argv, VALUE os)
+{
+    rb_objspace_t *objspace = &rb_objspace;
+    VALUE obj, block, table;
+    st_data_t data;
+
+    rb_scan_args(argc, argv, "11", &obj, &block);
+    rb_check_frozen(obj);
+    if (argc == 1) {
+	block = rb_block_proc();
+    }
+    else if (!rb_respond_to(block, rb_intern("call"))) {
+	rb_raise(rb_eArgError, "wrong type argument %s (should be callable)",
+		 rb_obj_classname(block));
+    }
+    if (!FL_ABLE(obj)) {
+	rb_raise(rb_eArgError, "cannot define finalizer for %s",
+		 rb_obj_classname(obj));
+    }
+    RBASIC(obj)->flags |= FL_FINALIZE;
+
+    block = rb_ary_new3(2, INT2FIX(rb_safe_level()), block);
+    OBJ_FREEZE(block);
+
+    if (st_lookup(finalizer_table, obj, &data)) {
+	table = (VALUE)data;
+	rb_ary_push(table, block);
+    }
+    else {
+	table = rb_ary_new3(1, block);
+	RBASIC(table)->klass = 0;
+	st_add_direct(finalizer_table, obj, table);
+    }
+    return block;
+}
+
+void
+rb_gc_copy_finalizer(VALUE dest, VALUE obj)
+{
+    rb_objspace_t *objspace = &rb_objspace;
+    VALUE table;
+    st_data_t data;
+
+    if (!FL_TEST(obj, FL_FINALIZE)) return;
+    if (st_lookup(finalizer_table, obj, &data)) {
+	table = (VALUE)data;
+	st_insert(finalizer_table, dest, table);
+    }
+    FL_SET(dest, FL_FINALIZE);
+}
+
+static VALUE
+run_single_final(VALUE arg)
+{
+    VALUE *args = (VALUE *)arg;
+    rb_eval_cmd(args[0], args[1], (int)args[2]);
+    return Qnil;
+}
+
+static void
+run_finalizer(rb_objspace_t *objspace, VALUE objid, VALUE table)
+{
+    long i;
+    int status;
+    VALUE args[3];
+
+    if (RARRAY_LEN(table) > 0) {
+	args[1] = rb_obj_freeze(rb_ary_new3(1, objid));
+    }
+    else {
+	args[1] = 0;
+    }
+
+    args[2] = (VALUE)rb_safe_level();
+    for (i=0; i<RARRAY_LEN(table); i++) {
+	VALUE final = RARRAY_PTR(table)[i];
+	args[0] = RARRAY_PTR(final)[1];
+	args[2] = FIX2INT(RARRAY_PTR(final)[0]);
+	status = 0;
+	rb_protect(run_single_final, (VALUE)args, &status);
+	if (status)
+	    rb_set_errinfo(Qnil);
+    }
+}
+
+static void
+run_final(rb_objspace_t *objspace, VALUE obj)
+{
+    VALUE objid;
+    RUBY_DATA_FUNC free_func = 0;
+    st_data_t key, table;
+
+    objspace->heap.final_num--;
+
+    objid = rb_obj_id(obj);	/* make obj into id */
+    RBASIC(obj)->klass = 0;
+
+    if (RTYPEDDATA_P(obj)) {
+	free_func = RTYPEDDATA_TYPE(obj)->function.dfree;
+    }
+    else {
+	free_func = RDATA(obj)->dfree;
+    }
+    if (free_func) {
+	(*free_func)(DATA_PTR(obj));
+    }
+
+    key = (st_data_t)obj;
+    if (st_delete(finalizer_table, &key, &table)) {
+	run_finalizer(objspace, objid, (VALUE)table);
+    }
+}
+
+static void
+finalize_deferred(rb_objspace_t *objspace)
+{
+    RVALUE *p = deferred_final_list;
+    deferred_final_list = 0;
+
+    if (p) {
+	finalize_list(objspace, p);
+    }
+}
+
+void
+rb_gc_finalize_deferred(void)
+{
+    finalize_deferred(&rb_objspace);
+}
+
+static int
+chain_finalized_object(st_data_t key, st_data_t val, st_data_t arg)
+{
+    RVALUE *p = (RVALUE *)key, **final_list = (RVALUE **)arg;
+    if ((p->as.basic.flags & (FL_FINALIZE|FL_MARK)) == FL_FINALIZE) {
+	if (BUILTIN_TYPE(p) != T_ZOMBIE) {
+	    p->as.free.flags = FL_MARK | T_ZOMBIE; /* remain marked */
+	    RDATA(p)->dfree = 0;
+	}
+	p->as.free.next = *final_list;
+	*final_list = p;
+    }
+    return ST_CONTINUE;
+}
+
+struct force_finalize_list {
+    VALUE obj;
+    VALUE table;
+    struct force_finalize_list *next;
+};
+
+static int
+force_chain_object(st_data_t key, st_data_t val, st_data_t arg)
+{
+    struct force_finalize_list **prev = (struct force_finalize_list **)arg;
+    struct force_finalize_list *curr = ALLOC(struct force_finalize_list);
+    curr->obj = key;
+    curr->table = val;
+    curr->next = *prev;
+    *prev = curr;
+    return ST_CONTINUE;
+}
+
+void
+rb_gc_call_finalizer_at_exit(void)
+{
+    rb_objspace_call_finalizer(&rb_objspace);
+}
+
+static void
+rb_objspace_call_finalizer(rb_objspace_t *objspace)
+{
+    RVALUE *p, *pend;
+    RVALUE *final_list = 0;
+    size_t i;
+
+    /* run finalizers */
+    rest_sweep(objspace);
+
+    do {
+	/* XXX: this loop will make no sense */
+	/* because mark will not be removed */
+	finalize_deferred(objspace);
+	mark_tbl(objspace, finalizer_table, 0);
+	st_foreach(finalizer_table, chain_finalized_object,
+		   (st_data_t)&deferred_final_list);
+    } while (deferred_final_list);
+    /* force to run finalizer */
+    while (finalizer_table->num_entries) {
+	struct force_finalize_list *list = 0;
+	st_foreach(finalizer_table, force_chain_object, (st_data_t)&list);
+	while (list) {
+	    struct force_finalize_list *curr = list;
+	    run_finalizer(objspace, rb_obj_id(curr->obj), curr->table);
+	    st_delete(finalizer_table, (st_data_t*)&curr->obj, 0);
+	    list = curr->next;
+	    xfree(curr);
+	}
+    }
+
+    /* finalizers are part of garbage collection */
+    during_gc++;
+
+    /* run data object's finalizers */
+    for (i = 0; i < heaps_used; i++) {
+	p = objspace->heap.sorted[i].start; pend = objspace->heap.sorted[i].end;
+	while (p < pend) {
+	    if (BUILTIN_TYPE(p) == T_DATA &&
+		DATA_PTR(p) && RANY(p)->as.data.dfree &&
+		!rb_obj_is_thread((VALUE)p) && !rb_obj_is_mutex((VALUE)p) &&
+		!rb_obj_is_fiber((VALUE)p)) {
+		p->as.free.flags = 0;
+		if (RTYPEDDATA_P(p)) {
+		    RDATA(p)->dfree = RANY(p)->as.typeddata.type->function.dfree;
+		}
+		if (RANY(p)->as.data.dfree == (RUBY_DATA_FUNC)-1) {
+		    xfree(DATA_PTR(p));
+		}
+		else if (RANY(p)->as.data.dfree) {
+		    make_deferred(RANY(p));
+		    RANY(p)->as.free.next = final_list;
+		    final_list = p;
+		}
+	    }
+	    else if (BUILTIN_TYPE(p) == T_FILE) {
+		if (RANY(p)->as.file.fptr) {
+		    make_io_deferred(RANY(p));
+		    RANY(p)->as.free.next = final_list;
+		    final_list = p;
+		}
+	    }
+	    p++;
+	}
+    }
+    during_gc = 0;
+    if (final_list) {
+	finalize_list(objspace, final_list);
+    }
+
+    st_free_table(finalizer_table);
+    finalizer_table = 0;
+}
+
+void
+rb_gc(void)
+{
+    rb_objspace_t *objspace = &rb_objspace;
+    garbage_collect(objspace);
+    finalize_deferred(objspace);
+    free_unused_heaps(objspace);
+}
+
+/*
+ *  call-seq:
+ *     ObjectSpace._id2ref(object_id) -> an_object
+ *
+ *  Converts an object id to a reference to the object. May not be
+ *  called on an object id passed as a parameter to a finalizer.
+ *
+ *     s = "I am a string"                    #=> "I am a string"
+ *     r = ObjectSpace._id2ref(s.object_id)   #=> "I am a string"
+ *     r == s                                 #=> true
+ *
+ */
+
+static VALUE
+id2ref(VALUE obj, VALUE objid)
+{
+#if SIZEOF_LONG == SIZEOF_VOIDP
+#define NUM2PTR(x) NUM2ULONG(x)
+#elif SIZEOF_LONG_LONG == SIZEOF_VOIDP
+#define NUM2PTR(x) NUM2ULL(x)
+#endif
+    rb_objspace_t *objspace = &rb_objspace;
+    VALUE ptr;
+    void *p0;
+
+    rb_secure(4);
+    ptr = NUM2PTR(objid);
+    p0 = (void *)ptr;
+
+    if (ptr == Qtrue) return Qtrue;
+    if (ptr == Qfalse) return Qfalse;
+    if (ptr == Qnil) return Qnil;
+    if (FIXNUM_P(ptr)) return (VALUE)ptr;
+    ptr = objid ^ FIXNUM_FLAG;	/* unset FIXNUM_FLAG */
+
+    if ((ptr % sizeof(RVALUE)) == (4 << 2)) {
+        ID symid = ptr / sizeof(RVALUE);
+        if (rb_id2name(symid) == 0)
+	    rb_raise(rb_eRangeError, "%p is not symbol id value", p0);
+	return ID2SYM(symid);
+    }
+
+    if (!is_pointer_to_heap(objspace, (void *)ptr) ||
+	BUILTIN_TYPE(ptr) > T_FIXNUM || BUILTIN_TYPE(ptr) == T_ICLASS) {
+	rb_raise(rb_eRangeError, "%p is not id value", p0);
+    }
+    if (BUILTIN_TYPE(ptr) == 0 || RBASIC(ptr)->klass == 0) {
+	rb_raise(rb_eRangeError, "%p is recycled object", p0);
+    }
+    return (VALUE)ptr;
+}
+
+/*
+ *  Document-method: __id__
+ *  Document-method: object_id
+ *
+ *  call-seq:
+ *     obj.__id__       -> fixnum
+ *     obj.object_id    -> fixnum
+ *
+ *  Returns an integer identifier for <i>obj</i>. The same number will
+ *  be returned on all calls to <code>id</code> for a given object, and
+ *  no two active objects will share an id.
+ *  <code>Object#object_id</code> is a different concept from the
+ *  <code>:name</code> notation, which returns the symbol id of
+ *  <code>name</code>. Replaces the deprecated <code>Object#id</code>.
+ */
+
+/*
+ *  call-seq:
+ *     obj.hash    -> fixnum
+ *
+ *  Generates a <code>Fixnum</code> hash value for this object. This
+ *  function must have the property that <code>a.eql?(b)</code> implies
+ *  <code>a.hash == b.hash</code>. The hash value is used by class
+ *  <code>Hash</code>. Any hash value that exceeds the capacity of a
+ *  <code>Fixnum</code> will be truncated before being used.
+ */
+
+VALUE
+rb_obj_id(VALUE obj)
+{
+    /*
+     *                32-bit VALUE space
+     *          MSB ------------------------ LSB
+     *  false   00000000000000000000000000000000
+     *  true    00000000000000000000000000000010
+     *  nil     00000000000000000000000000000100
+     *  undef   00000000000000000000000000000110
+     *  symbol  ssssssssssssssssssssssss00001110
+     *  object  oooooooooooooooooooooooooooooo00        = 0 (mod sizeof(RVALUE))
+     *  fixnum  fffffffffffffffffffffffffffffff1
+     *
+     *                    object_id space
+     *                                       LSB
+     *  false   00000000000000000000000000000000
+     *  true    00000000000000000000000000000010
+     *  nil     00000000000000000000000000000100
+     *  undef   00000000000000000000000000000110
+     *  symbol   000SSSSSSSSSSSSSSSSSSSSSSSSSSS0        S...S % A = 4 (S...S = s...s * A + 4)
+     *  object   oooooooooooooooooooooooooooooo0        o...o % A = 0
+     *  fixnum  fffffffffffffffffffffffffffffff1        bignum if required
+     *
+     *  where A = sizeof(RVALUE)/4
+     *
+     *  sizeof(RVALUE) is
+     *  20 if 32-bit, double is 4-byte aligned
+     *  24 if 32-bit, double is 8-byte aligned
+     *  40 if 64-bit
+     */
+    if (SYMBOL_P(obj)) {
+        return (SYM2ID(obj) * sizeof(RVALUE) + (4 << 2)) | FIXNUM_FLAG;
+    }
+    if (SPECIAL_CONST_P(obj)) {
+        return LONG2NUM((SIGNED_VALUE)obj);
+    }
+    return (VALUE)((SIGNED_VALUE)obj|FIXNUM_FLAG);
+}
+
+static int
+set_zero(st_data_t key, st_data_t val, st_data_t arg)
+{
+    VALUE k = (VALUE)key;
+    VALUE hash = (VALUE)arg;
+    rb_hash_aset(hash, k, INT2FIX(0));
+    return ST_CONTINUE;
+}
+
+/*
+ *  call-seq:
+ *     ObjectSpace.count_objects([result_hash]) -> hash
+ *
+ *  Counts objects for each type.
+ *
+ *  It returns a hash as:
+ *  {:TOTAL=>10000, :FREE=>3011, :T_OBJECT=>6, :T_CLASS=>404, ...}
+ *
+ *  If the optional argument, result_hash, is given,
+ *  it is overwritten and returned.
+ *  This is intended to avoid probe effect.
+ *
+ *  The contents of the returned hash is implementation defined.
+ *  It may be changed in future.
+ *
+ *  This method is not expected to work except C Ruby.
+ *
+ */
+
+static VALUE
+count_objects(int argc, VALUE *argv, VALUE os)
+{
+    rb_objspace_t *objspace = &rb_objspace;
+    size_t counts[T_MASK+1];
+    size_t freed = 0;
+    size_t total = 0;
+    size_t i;
+    VALUE hash;
+
+    if (rb_scan_args(argc, argv, "01", &hash) == 1) {
+        if (TYPE(hash) != T_HASH)
+            rb_raise(rb_eTypeError, "non-hash given");
+    }
+
+    for (i = 0; i <= T_MASK; i++) {
+        counts[i] = 0;
+    }
+
+    for (i = 0; i < heaps_used; i++) {
+        RVALUE *p, *pend;
+
+        p = objspace->heap.sorted[i].start; pend = objspace->heap.sorted[i].end;
+        for (;p < pend; p++) {
+            if (p->as.basic.flags) {
+                counts[BUILTIN_TYPE(p)]++;
+            }
+            else {
+                freed++;
+            }
+        }
+        total += objspace->heap.sorted[i].slot->limit;
+    }
+
+    if (hash == Qnil) {
+        hash = rb_hash_new();
+    }
+    else if (!RHASH_EMPTY_P(hash)) {
+        st_foreach(RHASH_TBL(hash), set_zero, hash);
+    }
+    rb_hash_aset(hash, ID2SYM(rb_intern("TOTAL")), SIZET2NUM(total));
+    rb_hash_aset(hash, ID2SYM(rb_intern("FREE")), SIZET2NUM(freed));
+
+    for (i = 0; i <= T_MASK; i++) {
+        VALUE type;
+        switch (i) {
+#define COUNT_TYPE(t) case (t): type = ID2SYM(rb_intern(#t)); break;
+	    COUNT_TYPE(T_NONE);
+	    COUNT_TYPE(T_OBJECT);
+	    COUNT_TYPE(T_CLASS);
+	    COUNT_TYPE(T_MODULE);
+	    COUNT_TYPE(T_FLOAT);
+	    COUNT_TYPE(T_STRING);
+	    COUNT_TYPE(T_REGEXP);
+	    COUNT_TYPE(T_ARRAY);
+	    COUNT_TYPE(T_HASH);
+	    COUNT_TYPE(T_STRUCT);
+	    COUNT_TYPE(T_BIGNUM);
+	    COUNT_TYPE(T_FILE);
+	    COUNT_TYPE(T_DATA);
+	    COUNT_TYPE(T_MATCH);
+	    COUNT_TYPE(T_COMPLEX);
+	    COUNT_TYPE(T_RATIONAL);
+	    COUNT_TYPE(T_NIL);
+	    COUNT_TYPE(T_TRUE);
+	    COUNT_TYPE(T_FALSE);
+	    COUNT_TYPE(T_SYMBOL);
+	    COUNT_TYPE(T_FIXNUM);
+	    COUNT_TYPE(T_UNDEF);
+	    COUNT_TYPE(T_NODE);
+	    COUNT_TYPE(T_ICLASS);
+	    COUNT_TYPE(T_ZOMBIE);
+#undef COUNT_TYPE
+          default:              type = INT2NUM(i); break;
+        }
+        if (counts[i])
+            rb_hash_aset(hash, type, SIZET2NUM(counts[i]));
+    }
+
+    return hash;
+}
+
+/*
+ *  call-seq:
+ *     GC.count -> Integer
+ *
+ *  The number of times GC occurred.
+ *
+ *  It returns the number of times GC occurred since the process started.
+ *
+ */
+
+static VALUE
+gc_count(VALUE self)
+{
+    return UINT2NUM((&rb_objspace)->count);
+}
+
+/*
+ *  call-seq:
+ *     GC.stat -> Hash
+ *
+ *  Returns a Hash containing information about the GC.
+ *
+ *  The hash includes information about internal statistics about GC such as:
+ *
+ *    {
+ *      :count          => 18,
+ *      :heap_used      => 77,
+ *      :heap_length    => 77,
+ *      :heap_increment => 0,
+ *      :heap_live_num  => 23287,
+ *      :heap_free_num  => 8115,
+ *      :heap_final_num => 0,
+ *    }
+ *
+ *  The contents of the hash are implementation defined and may be changed in
+ *  the future.
+ *
+ *  This method is only expected to work on C Ruby.
+ *
+ */
+
+static VALUE
+gc_stat(int argc, VALUE *argv, VALUE self)
+{
+    rb_objspace_t *objspace = &rb_objspace;
+    VALUE hash;
+
+    if (rb_scan_args(argc, argv, "01", &hash) == 1) {
+        if (TYPE(hash) != T_HASH)
+            rb_raise(rb_eTypeError, "non-hash given");
+    }
+
+    if (hash == Qnil) {
+        hash = rb_hash_new();
+    }
+
+    rest_sweep(objspace);
+
+    rb_hash_aset(hash, ID2SYM(rb_intern("count")), SIZET2NUM(objspace->count));
+
+    /* implementation dependent counters */
+    rb_hash_aset(hash, ID2SYM(rb_intern("heap_used")), SIZET2NUM(objspace->heap.used));
+    rb_hash_aset(hash, ID2SYM(rb_intern("heap_length")), SIZET2NUM(objspace->heap.length));
+    rb_hash_aset(hash, ID2SYM(rb_intern("heap_increment")), SIZET2NUM(objspace->heap.increment));
+    rb_hash_aset(hash, ID2SYM(rb_intern("heap_live_num")), SIZET2NUM(objspace->heap.live_num));
+    rb_hash_aset(hash, ID2SYM(rb_intern("heap_free_num")), SIZET2NUM(objspace->heap.free_num));
+    rb_hash_aset(hash, ID2SYM(rb_intern("heap_final_num")), SIZET2NUM(objspace->heap.final_num));
+    return hash;
+}
+
+
+#if CALC_EXACT_MALLOC_SIZE
+/*
+ *  call-seq:
+ *     GC.malloc_allocated_size -> Integer
+ *
+ *  The allocated size by malloc().
+ *
+ *  It returns the allocated size by malloc().
+ */
+
+static VALUE
+gc_malloc_allocated_size(VALUE self)
+{
+    return UINT2NUM((&rb_objspace)->malloc_params.allocated_size);
+}
+
+/*
+ *  call-seq:
+ *     GC.malloc_allocations -> Integer
+ *
+ *  The number of allocated memory object by malloc().
+ *
+ *  It returns the number of allocated memory object by malloc().
+ */
+
+static VALUE
+gc_malloc_allocations(VALUE self)
+{
+    return UINT2NUM((&rb_objspace)->malloc_params.allocations);
+}
+#endif
+
+static VALUE
+gc_profile_record_get(void)
+{
+    VALUE prof;
+    VALUE gc_profile = rb_ary_new();
+    size_t i;
+    rb_objspace_t *objspace = (&rb_objspace);
+
+    if (!objspace->profile.run) {
+	return Qnil;
+    }
+
+    for (i =0; i < objspace->profile.count; i++) {
+	prof = rb_hash_new();
+        rb_hash_aset(prof, ID2SYM(rb_intern("GC_TIME")), DBL2NUM(objspace->profile.record[i].gc_time));
+        rb_hash_aset(prof, ID2SYM(rb_intern("GC_INVOKE_TIME")), DBL2NUM(objspace->profile.record[i].gc_invoke_time));
+        rb_hash_aset(prof, ID2SYM(rb_intern("HEAP_USE_SIZE")), SIZET2NUM(objspace->profile.record[i].heap_use_size));
+        rb_hash_aset(prof, ID2SYM(rb_intern("HEAP_TOTAL_SIZE")), SIZET2NUM(objspace->profile.record[i].heap_total_size));
+        rb_hash_aset(prof, ID2SYM(rb_intern("HEAP_TOTAL_OBJECTS")), SIZET2NUM(objspace->profile.record[i].heap_total_objects));
+        rb_hash_aset(prof, ID2SYM(rb_intern("GC_IS_MARKED")), objspace->profile.record[i].is_marked);
+#if GC_PROFILE_MORE_DETAIL
+        rb_hash_aset(prof, ID2SYM(rb_intern("GC_MARK_TIME")), DBL2NUM(objspace->profile.record[i].gc_mark_time));
+        rb_hash_aset(prof, ID2SYM(rb_intern("GC_SWEEP_TIME")), DBL2NUM(objspace->profile.record[i].gc_sweep_time));
+        rb_hash_aset(prof, ID2SYM(rb_intern("ALLOCATE_INCREASE")), SIZET2NUM(objspace->profile.record[i].allocate_increase));
+        rb_hash_aset(prof, ID2SYM(rb_intern("ALLOCATE_LIMIT")), SIZET2NUM(objspace->profile.record[i].allocate_limit));
+        rb_hash_aset(prof, ID2SYM(rb_intern("HEAP_USE_SLOTS")), SIZET2NUM(objspace->profile.record[i].heap_use_slots));
+        rb_hash_aset(prof, ID2SYM(rb_intern("HEAP_LIVE_OBJECTS")), SIZET2NUM(objspace->profile.record[i].heap_live_objects));
+        rb_hash_aset(prof, ID2SYM(rb_intern("HEAP_FREE_OBJECTS")), SIZET2NUM(objspace->profile.record[i].heap_free_objects));
+        rb_hash_aset(prof, ID2SYM(rb_intern("HAVE_FINALIZE")), objspace->profile.record[i].have_finalize);
+#endif
+	rb_ary_push(gc_profile, prof);
+    }
+
+    return gc_profile;
+}
+
+/*
+ *  call-seq:
+ *     GC::Profiler.result -> String
+ *
+ *  Returns a profile data report such as:
+ *
+ *    GC 1 invokes.
+ *    Index    Invoke Time(sec)       Use Size(byte)     Total Size(byte)         Total Object                    GC time(ms)
+ *        1               0.012               159240               212940                10647         0.00000000000001530000
+ */
+
+static VALUE
+gc_profile_result(void)
+{
+    rb_objspace_t *objspace = &rb_objspace;
+    VALUE record;
+    VALUE result;
+    int i, index;
+
+    record = gc_profile_record_get();
+    if (objspace->profile.run && objspace->profile.count) {
+	result = rb_sprintf("GC %d invokes.\n", NUM2INT(gc_count(0)));
+        index = 1;
+	rb_str_cat2(result, "Index    Invoke Time(sec)       Use Size(byte)     Total Size(byte)         Total Object                    GC Time(ms)\n");
+	for (i = 0; i < (int)RARRAY_LEN(record); i++) {
+	    VALUE r = RARRAY_PTR(record)[i];
+#if !GC_PROFILE_MORE_DETAIL
+            if (rb_hash_aref(r, ID2SYM(rb_intern("GC_IS_MARKED")))) {
+#endif
+	    rb_str_catf(result, "%5d %19.3f %20"PRIuSIZE" %20"PRIuSIZE" %20"PRIuSIZE" %30.20f\n",
+			index++, NUM2DBL(rb_hash_aref(r, ID2SYM(rb_intern("GC_INVOKE_TIME")))),
+			(size_t)NUM2SIZET(rb_hash_aref(r, ID2SYM(rb_intern("HEAP_USE_SIZE")))),
+			(size_t)NUM2SIZET(rb_hash_aref(r, ID2SYM(rb_intern("HEAP_TOTAL_SIZE")))),
+			(size_t)NUM2SIZET(rb_hash_aref(r, ID2SYM(rb_intern("HEAP_TOTAL_OBJECTS")))),
+			NUM2DBL(rb_hash_aref(r, ID2SYM(rb_intern("GC_TIME"))))*1000);
+#if !GC_PROFILE_MORE_DETAIL
+            }
+#endif
+	}
+#if GC_PROFILE_MORE_DETAIL
+	rb_str_cat2(result, "\n\n");
+	rb_str_cat2(result, "More detail.\n");
+	rb_str_cat2(result, "Index Allocate Increase    Allocate Limit  Use Slot  Have Finalize             Mark Time(ms)            Sweep Time(ms)\n");
+        index = 1;
+	for (i = 0; i < (int)RARRAY_LEN(record); i++) {
+	    VALUE r = RARRAY_PTR(record)[i];
+	    rb_str_catf(result, "%5d %17"PRIuSIZE" %17"PRIuSIZE" %9"PRIuSIZE" %14s %25.20f %25.20f\n",
+			index++, (size_t)NUM2SIZET(rb_hash_aref(r, ID2SYM(rb_intern("ALLOCATE_INCREASE")))),
+			(size_t)NUM2SIZET(rb_hash_aref(r, ID2SYM(rb_intern("ALLOCATE_LIMIT")))),
+			(size_t)NUM2SIZET(rb_hash_aref(r, ID2SYM(rb_intern("HEAP_USE_SLOTS")))),
+			rb_hash_aref(r, ID2SYM(rb_intern("HAVE_FINALIZE")))? "true" : "false",
+			NUM2DBL(rb_hash_aref(r, ID2SYM(rb_intern("GC_MARK_TIME"))))*1000,
+			NUM2DBL(rb_hash_aref(r, ID2SYM(rb_intern("GC_SWEEP_TIME"))))*1000);
+	}
+#endif
+    }
+    else {
+	result = rb_str_new2("");
+    }
+    return result;
+}
+
+
+/*
+ *  call-seq:
+ *     GC::Profiler.report
+ *     GC::Profiler.report io
+ *
+ *  Writes the GC::Profiler#result to <tt>$stdout</tt> or the given IO object.
+ *
+ */
+
+static VALUE
+gc_profile_report(int argc, VALUE *argv, VALUE self)
+{
+    VALUE out;
+
+    if (argc == 0) {
+	out = rb_stdout;
+    }
+    else {
+	rb_scan_args(argc, argv, "01", &out);
+    }
+    rb_io_write(out, gc_profile_result());
+
+    return Qnil;
+}
+
+/*
+ *  call-seq:
+ *     GC::Profiler.total_time -> float
+ *
+ *  The total time used for garbage collection in milliseconds
+ */
+
+static VALUE
+gc_profile_total_time(VALUE self)
+{
+    double time = 0;
+    rb_objspace_t *objspace = &rb_objspace;
+    size_t i;
+
+    if (objspace->profile.run && objspace->profile.count) {
+	for (i = 0; i < objspace->profile.count; i++) {
+	    time += objspace->profile.record[i].gc_time;
+	}
+    }
+    return DBL2NUM(time);
+}
+
+/*  Document-class: GC::Profiler
+ *
+ *  The GC profiler provides access to information on GC runs including time,
+ *  length and object space size.
+ *
+ *  Example:
+ *
+ *    GC::Profiler.enable
+ *
+ *    require 'rdoc/rdoc'
+ *
+ *    puts GC::Profiler.result
+ *
+ *    GC::Profiler.disable
+ *
+ *  See also GC.count, GC.malloc_allocated_size and GC.malloc_allocations
+ */
+
+/*
+ *  The <code>GC</code> module provides an interface to Ruby's mark and
+ *  sweep garbage collection mechanism. Some of the underlying methods
+ *  are also available via the ObjectSpace module.
+ *
+ *  You may obtain information about the operation of the GC through
+ *  GC::Profiler.
+ */
+
+void
+Init_GC(void)
+{
+    VALUE rb_mObSpace;
+    VALUE rb_mProfiler;
+
+    rb_mGC = rb_define_module("GC");
+    rb_define_singleton_method(rb_mGC, "start", rb_gc_start, 0);
+    rb_define_singleton_method(rb_mGC, "enable", rb_gc_enable, 0);
+    rb_define_singleton_method(rb_mGC, "disable", rb_gc_disable, 0);
+    rb_define_singleton_method(rb_mGC, "stress", gc_stress_get, 0);
+    rb_define_singleton_method(rb_mGC, "stress=", gc_stress_set, 1);
+    rb_define_singleton_method(rb_mGC, "count", gc_count, 0);
+    rb_define_singleton_method(rb_mGC, "stat", gc_stat, -1);
+    rb_define_method(rb_mGC, "garbage_collect", rb_gc_start, 0);
+
+    rb_mProfiler = rb_define_module_under(rb_mGC, "Profiler");
+    rb_define_singleton_method(rb_mProfiler, "enabled?", gc_profile_enable_get, 0);
+    rb_define_singleton_method(rb_mProfiler, "enable", gc_profile_enable, 0);
+    rb_define_singleton_method(rb_mProfiler, "disable", gc_profile_disable, 0);
+    rb_define_singleton_method(rb_mProfiler, "clear", gc_profile_clear, 0);
+    rb_define_singleton_method(rb_mProfiler, "result", gc_profile_result, 0);
+    rb_define_singleton_method(rb_mProfiler, "report", gc_profile_report, -1);
+    rb_define_singleton_method(rb_mProfiler, "total_time", gc_profile_total_time, 0);
+
+    rb_mObSpace = rb_define_module("ObjectSpace");
+    rb_define_module_function(rb_mObSpace, "each_object", os_each_obj, -1);
+    rb_define_module_function(rb_mObSpace, "garbage_collect", rb_gc_start, 0);
+
+    rb_define_module_function(rb_mObSpace, "define_finalizer", define_final, -1);
+    rb_define_module_function(rb_mObSpace, "undefine_finalizer", undefine_final, 1);
+
+    rb_define_module_function(rb_mObSpace, "_id2ref", id2ref, 1);
+
+    nomem_error = rb_exc_new3(rb_eNoMemError,
+			      rb_obj_freeze(rb_str_new2("failed to allocate memory")));
+    OBJ_TAINT(nomem_error);
+    OBJ_FREEZE(nomem_error);
+
+    rb_define_method(rb_cBasicObject, "__id__", rb_obj_id, 0);
+    rb_define_method(rb_mKernel, "object_id", rb_obj_id, 0);
+
+    rb_define_module_function(rb_mObSpace, "count_objects", count_objects, -1);
+
+#if CALC_EXACT_MALLOC_SIZE
+    rb_define_singleton_method(rb_mGC, "malloc_allocated_size", gc_malloc_allocated_size, 0);
+    rb_define_singleton_method(rb_mGC, "malloc_allocations", gc_malloc_allocations, 0);
+#endif
+}