src/runtime/gc-internal.h

   1 /*
   2  * garbage collection - shared definitions for modules "inside" the GC system
   3  */
   4
   5 /*
   6  * This software is part of the SBCL system. See the README file for
   7  * more information.
   8  *
   9  * This software is derived from the CMU CL system, which was
  10  * written at Carnegie Mellon University and released into the
  11  * public domain. The software is in the public domain and is
  12  * provided with absolutely no warranty. See the COPYING and CREDITS
  13  * files for more information.
  14  */
  15
  16 #ifndef _GC_INTERNAL_H_
  17 #define _GC_INTERNAL_H_
  18
  19 #include "genesis/simple-fun.h"
  20 #include "thread.h"
  21 #include "interr.h"
  22
  23 #ifdef LISP_FEATURE_GENCGC
  24 #include "gencgc-internal.h"
  25 #else
  26 #include "cheneygc-internal.h"
  27 #endif
  28
  29 /* disabling gc assertions made no discernable difference to GC speed,
  30  * last I tried it - dan 2003.12.21
  31  *
  32  * And it's unsafe to do so while things like gc_assert(0 ==
  33  * thread_mutex_lock(&allocation_lock)) exist. - MG 2009-01-13
  34  */
  35 #if 1
  36 # define gc_assert(ex)                                                 \
  37 do {                                                                   \
  38     if (!(ex)) gc_abort();                                             \
  39 } while (0)
  40 # define gc_assert_verbose(ex, fmt, ...)                               \
  41 do {                                                                   \
  42     if (!(ex)) {                                                       \
  43         fprintf(stderr, fmt, ## __VA_ARGS__);                          \
  44         gc_abort();                                                    \
  45     }                                                                  \
  46 } while (0)
  47 #else
  48 # define gc_assert(ex)
  49 # define gc_assert_verbose(ex, fmt, ...)
  50 #endif
  51
  52 #define gc_abort()                                                     \
  53   lose("GC invariant lost, file \"%s\", line %d\n", __FILE__, __LINE__)
  54
  55 #define CEILING(x,y) (((x) + ((y) - 1)) & (~((y) - 1)))
  56
  57 static inline uword_t
  58 NWORDS(uword_t x, uword_t n_bits)
  59 {
  60     /* A good compiler should be able to constant-fold this whole thing,
  61        even with the conditional. */
  62     if(n_bits <= N_WORD_BITS) {
  63         uword_t elements_per_word = N_WORD_BITS/n_bits;
  64
  65         return CEILING(x, elements_per_word)/elements_per_word;
  66     }
  67     else {
  68         /* FIXME: should have some sort of assertion that N_WORD_BITS
  69            evenly divides n_bits */
  70         return x * (n_bits/N_WORD_BITS);
  71     }
  72 }
  73
  74 /* FIXME: Shouldn't this be defined in sbcl.h? */
  75
  76 #if defined(LISP_FEATURE_SPARC) || defined(LISP_FEATURE_ARM)
  77 #define FUN_RAW_ADDR_OFFSET 0
  78 #else
  79 #define FUN_RAW_ADDR_OFFSET (offsetof(struct simple_fun, code) - FUN_POINTER_LOWTAG)
  80 #endif
  81
  82 #define SIMPLE_FUN_SCAV_START(fun_ptr) &fun_ptr->name
  83 #define SIMPLE_FUN_SCAV_NWORDS(fun_ptr) ((lispobj*)fun_ptr->code - &fun_ptr->name)
  84
  85 /* values for the *_alloc_* parameters, also see the commentary for
  86  * struct page in gencgc-internal.h.  FIXME: Perhaps these constants
  87  * should be there, or at least defined on gencgc only? */
  88 #define FREE_PAGE_FLAG 0
  89 #define BOXED_PAGE_FLAG 1
  90 #define UNBOXED_PAGE_FLAG 2
  91 #define OPEN_REGION_PAGE_FLAG 4
  92 #define CODE_PAGE_FLAG        (BOXED_PAGE_FLAG|UNBOXED_PAGE_FLAG)
  93
  94 #define ALLOC_BOXED 0
  95 #define ALLOC_UNBOXED 1
  96 #define ALLOC_QUICK 1
  97
  98 #ifdef LISP_FEATURE_GENCGC
  99 #include "gencgc-alloc-region.h"
 100 void *
 101 gc_alloc_with_region(sword_t nbytes,int page_type_flag, struct alloc_region *my_region,
 102                      int quick_p);
 103 static inline void *
 104 gc_general_alloc(sword_t nbytes, int page_type_flag, int quick_p)
 105 {
 106     struct alloc_region *my_region;
 107     if (UNBOXED_PAGE_FLAG == page_type_flag) {
 108         my_region = &unboxed_region;
 109     } else if (BOXED_PAGE_FLAG & page_type_flag) {
 110         my_region = &boxed_region;
 111     } else {
 112         lose("bad page type flag: %d", page_type_flag);
 113     }
 114     return gc_alloc_with_region(nbytes, page_type_flag, my_region, quick_p);
 115 }
 116 #else
 117 extern void *gc_general_alloc(word_t nbytes,int page_type_flag,int quick_p);
 118 #endif
 119
 120 static inline lispobj
 121 gc_general_copy_object(lispobj object, long nwords, int page_type_flag)
 122 {
 123     lispobj *new;
 124
 125     gc_assert(is_lisp_pointer(object));
 126     gc_assert(from_space_p(object));
 127     gc_assert((nwords & 0x01) == 0);
 128
 129     /* Allocate space. */
 130     new = gc_general_alloc(nwords*N_WORD_BYTES, page_type_flag, ALLOC_QUICK);
 131
 132     /* Copy the object. */
 133     memcpy(new,native_pointer(object),nwords*N_WORD_BYTES);
 134
 135     return make_lispobj(new, lowtag_of(object));
 136 }
 137
 138 extern sword_t (*scavtab[256])(lispobj *where, lispobj object);
 139 extern lispobj (*transother[256])(lispobj object);
 140 extern sword_t (*sizetab[256])(lispobj *where);
 141
 142 extern struct weak_pointer *weak_pointers; /* in gc-common.c */
 143 extern struct hash_table *weak_hash_tables; /* in gc-common.c */
 144
 145 extern void scavenge(lispobj *start, sword_t n_words);
 146 extern void scavenge_interrupt_contexts(struct thread *thread);
 147 extern void scav_weak_hash_tables(void);
 148 extern void scan_weak_hash_tables(void);
 149 extern void scan_weak_pointers(void);
 150
 151 lispobj  copy_large_unboxed_object(lispobj object, sword_t nwords);
 152 lispobj  copy_unboxed_object(lispobj object, sword_t nwords);
 153 lispobj  copy_large_object(lispobj object, sword_t nwords);
 154 lispobj  copy_object(lispobj object, sword_t nwords);
 155 lispobj  copy_code_object(lispobj object, sword_t nwords);
 156
 157 lispobj *search_read_only_space(void *pointer);
 158 lispobj *search_static_space(void *pointer);
 159 lispobj *search_immobile_space(void *pointer);
 160 lispobj *search_dynamic_space(void *pointer);
 161
 162 lispobj *gc_search_space(lispobj *start, size_t words, lispobj *pointer);
 163
 164 extern int looks_like_valid_lisp_pointer_p(lispobj pointer, lispobj *start_addr);
 165
 166 extern void scavenge_control_stack(struct thread *th);
 167 extern void scrub_control_stack(void);
 168 extern void scrub_thread_control_stack(struct thread *);
 169
 170 #include "fixnump.h"
 171
 172 #ifdef LISP_FEATURE_GENCGC
 173 #include "gencgc-internal.h"
 174 #else
 175 #include "cheneygc-internal.h"
 176 #endif
 177
 178 #if N_WORD_BITS == 32
 179 # define SIMPLE_ARRAY_WORD_WIDETAG SIMPLE_ARRAY_UNSIGNED_BYTE_32_WIDETAG
 180 #elif N_WORD_BITS == 64
 181 # define SIMPLE_ARRAY_WORD_WIDETAG SIMPLE_ARRAY_UNSIGNED_BYTE_64_WIDETAG
 182 #endif
 183
 184 extern void
 185 instance_scan_interleaved(void (*proc)(),
 186                           lispobj *instance_ptr,
 187                           sword_t n_words,
 188                           lispobj *layout_obj);
 189
 190 // Generalization of instance_scan_interleaved
 191 #define BIT_SCAN_INVERT 1
 192 #define BIT_SCAN_CLEAR  2
 193 typedef uword_t in_use_marker_t;
 194 extern void
 195 bitmap_scan(in_use_marker_t* bitmap, int n_bitmap_words, int flags,
 196             void (*proc)(void*, int, int), void* arg);
 197
 198 #ifdef LISP_FEATURE_IMMOBILE_SPACE
 199
 200 static inline boolean immobile_space_p(lispobj obj)
 201 {
 202   return IMMOBILE_SPACE_START <= obj && obj < IMMOBILE_SPACE_END;
 203 }
 204
 205 // Note that find_page_index is in gencgc,
 206 // but because this is inline and needed by 2 files, it's in a header.
 207 typedef int low_page_index_t;
 208 static inline low_page_index_t find_immobile_page_index(void *addr)
 209 {
 210   if (addr >= (void*)IMMOBILE_SPACE_START) {
 211       // Must use full register size here to avoid truncation of quotient
 212       // and bogus result!
 213       page_index_t index =
 214           ((pointer_sized_uint_t)addr -
 215            (pointer_sized_uint_t)IMMOBILE_SPACE_START) / IMMOBILE_CARD_BYTES;
 216       if (index < (int)(IMMOBILE_SPACE_SIZE/IMMOBILE_CARD_BYTES))
 217           return index;
 218   }
 219   return -1;
 220 }
 221 int immobile_obj_younger_p(lispobj,generation_index_t);
 222 void promote_immobile_obj(lispobj*,int);
 223
 224 // Maximum number of boxed words in a code component
 225 #define CODE_HEADER_COUNT_MASK 0xFFFFFF
 226
 227 #define IMMOBILE_OBJ_VISITED_FLAG    0x10
 228 #define IMMOBILE_OBJ_GENERATION_MASK 0x0f // mask off the VISITED flag
 229
 230 #define IMMOBILE_VARYOBJ_SUBSPACE_START (IMMOBILE_SPACE_START+IMMOBILE_FIXEDOBJ_SUBSPACE_SIZE)
 231
 232 // Note: this does not work on a SIMPLE-FUN
 233 // because a simple-fun header does not contain a generation.
 234 #define __immobile_obj_generation(x) (__immobile_obj_gen_bits(x) & IMMOBILE_OBJ_GENERATION_MASK)
 235
 236 static inline struct code *code_obj_from_simple_fun(struct simple_fun *fun)
 237 {
 238   // The upper 4 bytes of any function header will point to its layout,
 239   // so mask those bytes off.
 240   uword_t offset = (HeaderValue(fun->header) & CODE_HEADER_COUNT_MASK)
 241                    * N_WORD_BYTES;
 242   return (struct code *)((uword_t)fun - offset);
 243 }
 244
 245 #ifdef LISP_FEATURE_LITTLE_ENDIAN
 246 static inline int immobile_obj_gen_bits(lispobj* pointer) // native pointer
 247 {
 248   if (widetag_of(*pointer) == SIMPLE_FUN_HEADER_WIDETAG)
 249     pointer = (lispobj*)code_obj_from_simple_fun((struct simple_fun*)pointer);
 250   return ((generation_index_t*)pointer)[3];
 251 }
 252 // Faster way when we know that the object can't be a simple-fun,
 253 // such as when walking the immobile space.
 254 static inline int __immobile_obj_gen_bits(lispobj* pointer) // native pointer
 255 {
 256   return ((generation_index_t*)pointer)[3];
 257 }
 258 #else
 259 #error "Need to define immobile_obj_gen_bits() for big-endian"
 260 #endif /* little-endian */
 261
 262 static inline boolean immobile_filler_p(lispobj* obj) {
 263   return *(int*)obj == (2<<N_WIDETAG_BITS | CODE_HEADER_WIDETAG);
 264 }
 265 #endif /* immobile space */
 266
 267 #endif /* _GC_INTERNAL_H_ */