Ruby 3.5.0dev (2025-01-10 revision 5fab31b15e32622c4b71d1d347a41937e9f9c212)
gc.h
1#ifndef INTERNAL_GC_H /*-*-C-*-vi:se ft=c:*/
2#define INTERNAL_GC_H
11#include "ruby/internal/config.h"
12
13#include <stddef.h> /* for size_t */
14
15#include "internal/compilers.h" /* for __has_attribute */
16#include "ruby/ruby.h" /* for rb_event_flag_t */
17#include "vm_core.h" /* for GET_EC() */
18
19#ifndef USE_MODULAR_GC
20# define USE_MODULAR_GC 0
21#endif
22
23#if defined(__x86_64__) && !defined(_ILP32) && defined(__GNUC__)
24#define SET_MACHINE_STACK_END(p) __asm__ __volatile__ ("movq\t%%rsp, %0" : "=r" (*(p)))
25#elif defined(__i386) && defined(__GNUC__)
26#define SET_MACHINE_STACK_END(p) __asm__ __volatile__ ("movl\t%%esp, %0" : "=r" (*(p)))
27#elif (defined(__powerpc__) || defined(__powerpc64__)) && defined(__GNUC__) && !defined(_AIX) && !defined(__APPLE__) // Not Apple is NEEDED to unbreak ppc64 build on Darwin. Don't ask.
28#define SET_MACHINE_STACK_END(p) __asm__ __volatile__ ("mr\t%0, %%r1" : "=r" (*(p)))
29#elif (defined(__powerpc__) || defined(__powerpc64__)) && defined(__GNUC__) && defined(_AIX)
30#define SET_MACHINE_STACK_END(p) __asm__ __volatile__ ("mr %0,1" : "=r" (*(p)))
31#elif defined(__POWERPC__) && defined(__APPLE__) // Darwin ppc and ppc64
32#define SET_MACHINE_STACK_END(p) __asm__ volatile("mr %0, r1" : "=r" (*(p)))
33#elif defined(__aarch64__) && defined(__GNUC__)
34#define SET_MACHINE_STACK_END(p) __asm__ __volatile__ ("mov\t%0, sp" : "=r" (*(p)))
35#else
36NOINLINE(void rb_gc_set_stack_end(VALUE **stack_end_p));
37#define SET_MACHINE_STACK_END(p) rb_gc_set_stack_end(p)
38#define USE_CONSERVATIVE_STACK_END
39#endif
40
41/* for GC debug */
42
43#ifndef RUBY_MARK_FREE_DEBUG
44#define RUBY_MARK_FREE_DEBUG 0
45#endif
46
47#if RUBY_MARK_FREE_DEBUG
48extern int ruby_gc_debug_indent;
49
50static inline void
51rb_gc_debug_indent(void)
52{
53 ruby_debug_printf("%*s", ruby_gc_debug_indent, "");
54}
55
56static inline void
57rb_gc_debug_body(const char *mode, const char *msg, int st, void *ptr)
58{
59 if (st == 0) {
60 ruby_gc_debug_indent--;
61 }
62 rb_gc_debug_indent();
63 ruby_debug_printf("%s: %s %s (%p)\n", mode, st ? "->" : "<-", msg, ptr);
64
65 if (st) {
66 ruby_gc_debug_indent++;
67 }
68
69 fflush(stdout);
70}
71
72#define RUBY_MARK_ENTER(msg) rb_gc_debug_body("mark", (msg), 1, ptr)
73#define RUBY_MARK_LEAVE(msg) rb_gc_debug_body("mark", (msg), 0, ptr)
74#define RUBY_FREE_ENTER(msg) rb_gc_debug_body("free", (msg), 1, ptr)
75#define RUBY_FREE_LEAVE(msg) rb_gc_debug_body("free", (msg), 0, ptr)
76#define RUBY_GC_INFO rb_gc_debug_indent(), ruby_debug_printf
77
78#else
79#define RUBY_MARK_ENTER(msg)
80#define RUBY_MARK_LEAVE(msg)
81#define RUBY_FREE_ENTER(msg)
82#define RUBY_FREE_LEAVE(msg)
83#define RUBY_GC_INFO if(0)printf
84#endif
85
86#define RUBY_FREE_UNLESS_NULL(ptr) if(ptr){ruby_xfree(ptr);(ptr)=NULL;}
87
88#if STACK_GROW_DIRECTION > 0
89# define STACK_UPPER(x, a, b) (a)
90#elif STACK_GROW_DIRECTION < 0
91# define STACK_UPPER(x, a, b) (b)
92#else
93RUBY_EXTERN int ruby_stack_grow_direction;
94int ruby_get_stack_grow_direction(volatile VALUE *addr);
95# define stack_growup_p(x) ( \
96 (ruby_stack_grow_direction ? \
97 ruby_stack_grow_direction : \
98 ruby_get_stack_grow_direction(x)) > 0)
99# define STACK_UPPER(x, a, b) (stack_growup_p(x) ? (a) : (b))
100#endif
101
102/*
103 STACK_GROW_DIR_DETECTION is used with STACK_DIR_UPPER.
104
105 On most normal systems, stacks grow from high address to lower address. In
106 this case, STACK_DIR_UPPER(a, b) will return (b), but on exotic systems where
107 the stack grows UP (from low address to high address), it will return (a).
108*/
109
110#if STACK_GROW_DIRECTION
111#define STACK_GROW_DIR_DETECTION
112#define STACK_DIR_UPPER(a,b) STACK_UPPER(0, (a), (b))
113#else
114#define STACK_GROW_DIR_DETECTION VALUE stack_grow_dir_detection
115#define STACK_DIR_UPPER(a,b) STACK_UPPER(&stack_grow_dir_detection, (a), (b))
116#endif
117#define IS_STACK_DIR_UPPER() STACK_DIR_UPPER(1,0)
118
119const char *rb_obj_info(VALUE obj);
120const char *rb_raw_obj_info(char *const buff, const size_t buff_size, VALUE obj);
121
122struct rb_execution_context_struct; /* in vm_core.h */
123struct rb_objspace; /* in vm_core.h */
124
125#define NEWOBJ_OF(var, T, c, f, s, ec) \
126 T *(var) = (T *)(((f) & FL_WB_PROTECTED) ? \
127 rb_wb_protected_newobj_of((ec ? ec : GET_EC()), (c), (f) & ~FL_WB_PROTECTED, s) : \
128 rb_wb_unprotected_newobj_of((c), (f), s))
129
130#define RB_OBJ_GC_FLAGS_MAX 6 /* used in ext/objspace */
131
132#ifndef USE_UNALIGNED_MEMBER_ACCESS
133# define UNALIGNED_MEMBER_ACCESS(expr) (expr)
134#elif ! USE_UNALIGNED_MEMBER_ACCESS
135# define UNALIGNED_MEMBER_ACCESS(expr) (expr)
136#elif ! (__has_warning("-Waddress-of-packed-member") || GCC_VERSION_SINCE(9, 0, 0))
137# define UNALIGNED_MEMBER_ACCESS(expr) (expr)
138#else
139# include "internal/warnings.h"
140# define UNALIGNED_MEMBER_ACCESS(expr) __extension__({ \
141 COMPILER_WARNING_PUSH; \
142 COMPILER_WARNING_IGNORED(-Waddress-of-packed-member); \
143 __typeof__(expr) unaligned_member_access_result = (expr); \
144 COMPILER_WARNING_POP; \
145 unaligned_member_access_result; \
146})
147
148# define UNALIGNED_MEMBER_PTR(ptr, mem) __extension__({ \
149 COMPILER_WARNING_PUSH; \
150 COMPILER_WARNING_IGNORED(-Waddress-of-packed-member); \
151 const volatile void *unaligned_member_ptr_result = &(ptr)->mem; \
152 COMPILER_WARNING_POP; \
153 (__typeof__((ptr)->mem) *)unaligned_member_ptr_result; \
154})
155#endif
156
157#ifndef UNALIGNED_MEMBER_PTR
158# define UNALIGNED_MEMBER_PTR(ptr, mem) UNALIGNED_MEMBER_ACCESS(&(ptr)->mem)
159#endif
160
161#define RB_OBJ_WRITE_UNALIGNED(old, slot, young) do { \
162 VALUE *_slot = UNALIGNED_MEMBER_ACCESS(slot); \
163 RB_OBJ_WRITE(old, _slot, young); \
164} while (0)
165
166/* Used in places that could malloc during, which can cause the GC to run. We
167 * need to temporarily disable the GC to allow the malloc to happen.
168 * Allocating memory during GC is a bad idea, so use this only when absolutely
169 * necessary. */
170#define DURING_GC_COULD_MALLOC_REGION_START() \
171 assert(rb_during_gc()); \
172 VALUE _already_disabled = rb_gc_disable_no_rest()
173
174#define DURING_GC_COULD_MALLOC_REGION_END() \
175 if (_already_disabled == Qfalse) rb_gc_enable()
176
177/* gc.c */
178RUBY_ATTR_MALLOC void *ruby_mimmalloc(size_t size);
179RUBY_ATTR_MALLOC void *ruby_mimcalloc(size_t num, size_t size);
180void ruby_mimfree(void *ptr);
181void rb_gc_prepare_heap(void);
182void rb_objspace_set_event_hook(const rb_event_flag_t event);
183VALUE rb_objspace_gc_enable(void *objspace);
184VALUE rb_objspace_gc_disable(void *objspace);
185void ruby_gc_set_params(void);
186void rb_gc_copy_attributes(VALUE dest, VALUE obj);
187size_t rb_size_mul_or_raise(size_t, size_t, VALUE); /* used in compile.c */
188size_t rb_size_mul_add_or_raise(size_t, size_t, size_t, VALUE); /* used in iseq.h */
189size_t rb_malloc_grow_capa(size_t current_capacity, size_t type_size);
190RUBY_ATTR_MALLOC void *rb_xmalloc_mul_add(size_t, size_t, size_t);
191RUBY_ATTR_MALLOC void *rb_xcalloc_mul_add(size_t, size_t, size_t);
192void *rb_xrealloc_mul_add(const void *, size_t, size_t, size_t);
193RUBY_ATTR_MALLOC void *rb_xmalloc_mul_add_mul(size_t, size_t, size_t, size_t);
194RUBY_ATTR_MALLOC void *rb_xcalloc_mul_add_mul(size_t, size_t, size_t, size_t);
195static inline void *ruby_sized_xrealloc_inlined(void *ptr, size_t new_size, size_t old_size) RUBY_ATTR_RETURNS_NONNULL RUBY_ATTR_ALLOC_SIZE((2));
196static inline void *ruby_sized_xrealloc2_inlined(void *ptr, size_t new_count, size_t elemsiz, size_t old_count) RUBY_ATTR_RETURNS_NONNULL RUBY_ATTR_ALLOC_SIZE((2, 3));
197static inline void ruby_sized_xfree_inlined(void *ptr, size_t size);
198
199void *rb_gc_ractor_cache_alloc(rb_ractor_t *ractor);
200void rb_gc_ractor_cache_free(void *cache);
201
202bool rb_gc_size_allocatable_p(size_t size);
203size_t *rb_gc_heap_sizes(void);
204size_t rb_gc_heap_id_for_size(size_t size);
205
206void rb_gc_mark_and_move(VALUE *ptr);
207
208void rb_gc_mark_weak(VALUE *ptr);
209void rb_gc_remove_weak(VALUE parent_obj, VALUE *ptr);
210
211void rb_gc_ref_update_table_values_only(st_table *tbl);
212
213void rb_gc_initial_stress_set(VALUE flag);
214
215void rb_gc_before_fork(void);
216void rb_gc_after_fork(rb_pid_t pid);
217
218#define rb_gc_mark_and_move_ptr(ptr) do { \
219 VALUE _obj = (VALUE)*(ptr); \
220 rb_gc_mark_and_move(&_obj); \
221 if (_obj != (VALUE)*(ptr)) *(ptr) = (void *)_obj; \
222} while (0)
223
224RUBY_SYMBOL_EXPORT_BEGIN
225/* exports for objspace module */
226void rb_objspace_reachable_objects_from(VALUE obj, void (func)(VALUE, void *), void *data);
227void rb_objspace_reachable_objects_from_root(void (func)(const char *category, VALUE, void *), void *data);
228int rb_objspace_internal_object_p(VALUE obj);
229int rb_objspace_garbage_object_p(VALUE obj);
230bool rb_gc_pointer_to_heap_p(VALUE obj);
231
232void rb_objspace_each_objects(
233 int (*callback)(void *start, void *end, size_t stride, void *data),
234 void *data);
235
236size_t rb_gc_obj_slot_size(VALUE obj);
237
238VALUE rb_gc_disable_no_rest(void);
239
240#define RB_GC_MAX_NAME_LEN 20
241
242/* gc.c (export) */
243const char *rb_objspace_data_type_name(VALUE obj);
244VALUE rb_wb_protected_newobj_of(struct rb_execution_context_struct *, VALUE, VALUE, size_t);
245VALUE rb_wb_unprotected_newobj_of(VALUE, VALUE, size_t);
246size_t rb_obj_memsize_of(VALUE);
247size_t rb_obj_gc_flags(VALUE, ID[], size_t);
248void rb_gc_mark_values(long n, const VALUE *values);
249void rb_gc_mark_vm_stack_values(long n, const VALUE *values);
250void rb_gc_update_values(long n, VALUE *values);
251void *ruby_sized_xrealloc(void *ptr, size_t new_size, size_t old_size) RUBY_ATTR_RETURNS_NONNULL RUBY_ATTR_ALLOC_SIZE((2));
252void *ruby_sized_xrealloc2(void *ptr, size_t new_count, size_t element_size, size_t old_count) RUBY_ATTR_RETURNS_NONNULL RUBY_ATTR_ALLOC_SIZE((2, 3));
253void ruby_sized_xfree(void *x, size_t size);
254
255const char *rb_gc_active_gc_name(void);
256int rb_gc_modular_gc_loaded_p(void);
257
258#if USE_MODULAR_GC
259void ruby_load_modular_gc_from_argv(int argc, char **argv);
260#endif
261RUBY_SYMBOL_EXPORT_END
262
263int rb_ec_stack_check(struct rb_execution_context_struct *ec);
264void rb_gc_writebarrier_remember(VALUE obj);
265const char *rb_obj_info(VALUE obj);
266void ruby_annotate_mmap(const void *addr, unsigned long size, const char *name);
267
268#if defined(HAVE_MALLOC_USABLE_SIZE) || defined(HAVE_MALLOC_SIZE) || defined(_WIN32)
269
270static inline void *
271ruby_sized_xrealloc_inlined(void *ptr, size_t new_size, size_t old_size)
272{
273 return ruby_xrealloc(ptr, new_size);
274}
275
276static inline void *
277ruby_sized_xrealloc2_inlined(void *ptr, size_t new_count, size_t elemsiz, size_t old_count)
278{
279 return ruby_xrealloc2(ptr, new_count, elemsiz);
280}
281
282static inline void
283ruby_sized_xfree_inlined(void *ptr, size_t size)
284{
285 ruby_xfree(ptr);
286}
287
288# define SIZED_REALLOC_N(x, y, z, w) REALLOC_N(x, y, z)
289
290static inline void *
291ruby_sized_realloc_n(void *ptr, size_t new_count, size_t element_size, size_t old_count)
292{
293 return ruby_xrealloc2(ptr, new_count, element_size);
294}
295
296#else
297
298static inline void *
299ruby_sized_xrealloc_inlined(void *ptr, size_t new_size, size_t old_size)
300{
301 return ruby_sized_xrealloc(ptr, new_size, old_size);
302}
303
304static inline void *
305ruby_sized_xrealloc2_inlined(void *ptr, size_t new_count, size_t elemsiz, size_t old_count)
306{
307 return ruby_sized_xrealloc2(ptr, new_count, elemsiz, old_count);
308}
309
310static inline void
311ruby_sized_xfree_inlined(void *ptr, size_t size)
312{
313 ruby_sized_xfree(ptr, size);
314}
315
316# define SIZED_REALLOC_N(v, T, m, n) \
317 ((v) = (T *)ruby_sized_xrealloc2((void *)(v), (m), sizeof(T), (n)))
318
319static inline void *
320ruby_sized_realloc_n(void *ptr, size_t new_count, size_t element_size, size_t old_count)
321{
322 return ruby_sized_xrealloc2(ptr, new_count, element_size, old_count);
323}
324
325#endif /* HAVE_MALLOC_USABLE_SIZE */
326
327#define ruby_sized_xrealloc ruby_sized_xrealloc_inlined
328#define ruby_sized_xrealloc2 ruby_sized_xrealloc2_inlined
329#define ruby_sized_xfree ruby_sized_xfree_inlined
330#endif /* INTERNAL_GC_H */
#define RUBY_EXTERN
Declaration of externally visible global variables.
Definition dllexport.h:45
uint32_t rb_event_flag_t
Represents event(s).
Definition event.h:108
Definition st.h:79
uintptr_t ID
Type that represents a Ruby identifier such as a variable name.
Definition value.h:52
uintptr_t VALUE
Type that represents a Ruby object.
Definition value.h:40