Annotation of OpenXM_contrib2/asir2000/gc/mark_rts.c, Revision 1.6
1.1 noro 1: /*
2: * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
3: * Copyright (c) 1991-1994 by Xerox Corporation. All rights reserved.
4: *
5: * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
6: * OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
7: *
8: * Permission is hereby granted to use or copy this program
9: * for any purpose, provided the above notices are retained on all copies.
10: * Permission to modify the code and to distribute modified code is granted,
11: * provided the above notices are retained, and a notice that the code was
12: * modified is included with the above copyright notice.
13: */
14: # include <stdio.h>
1.4 noro 15: # include "private/gc_priv.h"
1.1 noro 16:
17: /* Data structure for list of root sets. */
18: /* We keep a hash table, so that we can filter out duplicate additions. */
19: /* Under Win32, we need to do a better job of filtering overlaps, so */
20: /* we resort to sequential search, and pay the price. */
21: /* This is really declared in gc_priv.h:
22: struct roots {
23: ptr_t r_start;
24: ptr_t r_end;
1.4 noro 25: # if !defined(MSWIN32) && !defined(MSWINCE)
1.1 noro 26: struct roots * r_next;
27: # endif
28: GC_bool r_tmp;
29: -- Delete before registering new dynamic libraries
30: };
31:
32: struct roots GC_static_roots[MAX_ROOT_SETS];
33: */
34:
1.4 noro 35: int GC_no_dls = 0; /* Register dynamic library data segments. */
36:
1.1 noro 37: static int n_root_sets = 0;
38:
39: /* GC_static_roots[0..n_root_sets) contains the valid root sets. */
40:
41: # if !defined(NO_DEBUGGING)
42: /* For debugging: */
43: void GC_print_static_roots()
44: {
45: register int i;
46: size_t total = 0;
47:
48: for (i = 0; i < n_root_sets; i++) {
49: GC_printf2("From 0x%lx to 0x%lx ",
50: (unsigned long) GC_static_roots[i].r_start,
51: (unsigned long) GC_static_roots[i].r_end);
52: if (GC_static_roots[i].r_tmp) {
53: GC_printf0(" (temporary)\n");
54: } else {
55: GC_printf0("\n");
56: }
57: total += GC_static_roots[i].r_end - GC_static_roots[i].r_start;
58: }
59: GC_printf1("Total size: %ld\n", (unsigned long) total);
60: if (GC_root_size != total) {
61: GC_printf1("GC_root_size incorrect: %ld!!\n",
62: (unsigned long) GC_root_size);
63: }
64: }
65: # endif /* NO_DEBUGGING */
66:
67: /* Primarily for debugging support: */
68: /* Is the address p in one of the registered static */
69: /* root sections? */
70: GC_bool GC_is_static_root(p)
71: ptr_t p;
72: {
1.4 noro 73: static int last_root_set = MAX_ROOT_SETS;
1.1 noro 74: register int i;
75:
76:
1.4 noro 77: if (last_root_set < n_root_sets
78: && p >= GC_static_roots[last_root_set].r_start
1.1 noro 79: && p < GC_static_roots[last_root_set].r_end) return(TRUE);
80: for (i = 0; i < n_root_sets; i++) {
81: if (p >= GC_static_roots[i].r_start
82: && p < GC_static_roots[i].r_end) {
83: last_root_set = i;
84: return(TRUE);
85: }
86: }
87: return(FALSE);
88: }
89:
1.4 noro 90: #if !defined(MSWIN32) && !defined(MSWINCE)
1.1 noro 91: /*
92: # define LOG_RT_SIZE 6
93: # define RT_SIZE (1 << LOG_RT_SIZE) -- Power of 2, may be != MAX_ROOT_SETS
94:
95: struct roots * GC_root_index[RT_SIZE];
96: -- Hash table header. Used only to check whether a range is
97: -- already present.
98: -- really defined in gc_priv.h
99: */
100:
101: static int rt_hash(addr)
102: char * addr;
103: {
104: word result = (word) addr;
105: # if CPP_WORDSZ > 8*LOG_RT_SIZE
106: result ^= result >> 8*LOG_RT_SIZE;
107: # endif
108: # if CPP_WORDSZ > 4*LOG_RT_SIZE
109: result ^= result >> 4*LOG_RT_SIZE;
110: # endif
111: result ^= result >> 2*LOG_RT_SIZE;
112: result ^= result >> LOG_RT_SIZE;
113: result &= (RT_SIZE-1);
114: return(result);
115: }
116:
117: /* Is a range starting at b already in the table? If so return a */
118: /* pointer to it, else NIL. */
119: struct roots * GC_roots_present(b)
120: char *b;
121: {
122: register int h = rt_hash(b);
123: register struct roots *p = GC_root_index[h];
124:
125: while (p != 0) {
126: if (p -> r_start == (ptr_t)b) return(p);
127: p = p -> r_next;
128: }
129: return(FALSE);
130: }
131:
132: /* Add the given root structure to the index. */
133: static void add_roots_to_index(p)
134: struct roots *p;
135: {
136: register int h = rt_hash(p -> r_start);
137:
138: p -> r_next = GC_root_index[h];
139: GC_root_index[h] = p;
140: }
141:
1.4 noro 142: # else /* MSWIN32 || MSWINCE */
1.1 noro 143:
144: # define add_roots_to_index(p)
145:
146: # endif
147:
148:
149:
150:
151: word GC_root_size = 0;
152:
153: void GC_add_roots(b, e)
154: char * b; char * e;
155: {
156: DCL_LOCK_STATE;
157:
158: DISABLE_SIGNALS();
159: LOCK();
160: GC_add_roots_inner(b, e, FALSE);
161: UNLOCK();
162: ENABLE_SIGNALS();
163: }
164:
165:
166: /* Add [b,e) to the root set. Adding the same interval a second time */
167: /* is a moderately fast noop, and hence benign. We do not handle */
168: /* different but overlapping intervals efficiently. (We do handle */
169: /* them correctly.) */
170: /* Tmp specifies that the interval may be deleted before */
171: /* reregistering dynamic libraries. */
172: void GC_add_roots_inner(b, e, tmp)
173: char * b; char * e;
174: GC_bool tmp;
175: {
176: struct roots * old;
177:
1.4 noro 178: # if defined(MSWIN32) || defined(MSWINCE)
1.1 noro 179: /* Spend the time to ensure that there are no overlapping */
180: /* or adjacent intervals. */
181: /* This could be done faster with e.g. a */
182: /* balanced tree. But the execution time here is */
183: /* virtually guaranteed to be dominated by the time it */
184: /* takes to scan the roots. */
185: {
186: register int i;
187:
188: for (i = 0; i < n_root_sets; i++) {
189: old = GC_static_roots + i;
190: if ((ptr_t)b <= old -> r_end && (ptr_t)e >= old -> r_start) {
191: if ((ptr_t)b < old -> r_start) {
192: old -> r_start = (ptr_t)b;
193: GC_root_size += (old -> r_start - (ptr_t)b);
194: }
195: if ((ptr_t)e > old -> r_end) {
196: old -> r_end = (ptr_t)e;
197: GC_root_size += ((ptr_t)e - old -> r_end);
198: }
199: old -> r_tmp &= tmp;
200: break;
201: }
202: }
203: if (i < n_root_sets) {
204: /* merge other overlapping intervals */
205: struct roots *other;
206:
207: for (i++; i < n_root_sets; i++) {
208: other = GC_static_roots + i;
209: b = (char *)(other -> r_start);
210: e = (char *)(other -> r_end);
211: if ((ptr_t)b <= old -> r_end && (ptr_t)e >= old -> r_start) {
212: if ((ptr_t)b < old -> r_start) {
213: old -> r_start = (ptr_t)b;
214: GC_root_size += (old -> r_start - (ptr_t)b);
215: }
216: if ((ptr_t)e > old -> r_end) {
217: old -> r_end = (ptr_t)e;
218: GC_root_size += ((ptr_t)e - old -> r_end);
219: }
220: old -> r_tmp &= other -> r_tmp;
221: /* Delete this entry. */
222: GC_root_size -= (other -> r_end - other -> r_start);
223: other -> r_start = GC_static_roots[n_root_sets-1].r_start;
224: other -> r_end = GC_static_roots[n_root_sets-1].r_end;
225: n_root_sets--;
226: }
227: }
228: return;
229: }
230: }
231: # else
232: old = GC_roots_present(b);
233: if (old != 0) {
234: if ((ptr_t)e <= old -> r_end) /* already there */ return;
235: /* else extend */
236: GC_root_size += (ptr_t)e - old -> r_end;
237: old -> r_end = (ptr_t)e;
238: return;
239: }
240: # endif
241: if (n_root_sets == MAX_ROOT_SETS) {
242: ABORT("Too many root sets\n");
243: }
244: GC_static_roots[n_root_sets].r_start = (ptr_t)b;
245: GC_static_roots[n_root_sets].r_end = (ptr_t)e;
246: GC_static_roots[n_root_sets].r_tmp = tmp;
1.4 noro 247: # if !defined(MSWIN32) && !defined(MSWINCE)
1.1 noro 248: GC_static_roots[n_root_sets].r_next = 0;
249: # endif
250: add_roots_to_index(GC_static_roots + n_root_sets);
251: GC_root_size += (ptr_t)e - (ptr_t)b;
252: n_root_sets++;
253: }
254:
1.6 ! noro 255: static GC_bool roots_were_cleared = FALSE;
1.4 noro 256:
1.1 noro 257: void GC_clear_roots GC_PROTO((void))
258: {
259: DCL_LOCK_STATE;
260:
261: DISABLE_SIGNALS();
262: LOCK();
1.4 noro 263: roots_were_cleared = TRUE;
1.1 noro 264: n_root_sets = 0;
265: GC_root_size = 0;
1.4 noro 266: # if !defined(MSWIN32) && !defined(MSWINCE)
1.1 noro 267: {
268: register int i;
269:
270: for (i = 0; i < RT_SIZE; i++) GC_root_index[i] = 0;
271: }
272: # endif
273: UNLOCK();
274: ENABLE_SIGNALS();
275: }
276:
277: /* Internal use only; lock held. */
278: void GC_remove_tmp_roots()
279: {
280: register int i;
281:
282: for (i = 0; i < n_root_sets; ) {
283: if (GC_static_roots[i].r_tmp) {
284: GC_root_size -=
285: (GC_static_roots[i].r_end - GC_static_roots[i].r_start);
286: GC_static_roots[i].r_start = GC_static_roots[n_root_sets-1].r_start;
287: GC_static_roots[i].r_end = GC_static_roots[n_root_sets-1].r_end;
288: GC_static_roots[i].r_tmp = GC_static_roots[n_root_sets-1].r_tmp;
289: n_root_sets--;
290: } else {
291: i++;
292: }
293: }
1.4 noro 294: # if !defined(MSWIN32) && !defined(MSWINCE)
1.1 noro 295: {
296: register int i;
297:
298: for (i = 0; i < RT_SIZE; i++) GC_root_index[i] = 0;
299: for (i = 0; i < n_root_sets; i++)
300: add_roots_to_index(GC_static_roots + i);
301: }
302: # endif
303:
304: }
305:
1.4 noro 306: #if defined(MSWIN32) || defined(_WIN32_WCE_EMULATION)
307: /* Workaround for the OS mapping and unmapping behind our back: */
308: /* Is the address p in one of the temporary static root sections? */
309: GC_bool GC_is_tmp_root(p)
310: ptr_t p;
311: {
312: static int last_root_set = MAX_ROOT_SETS;
313: register int i;
314:
315: if (last_root_set < n_root_sets
316: && p >= GC_static_roots[last_root_set].r_start
317: && p < GC_static_roots[last_root_set].r_end)
318: return GC_static_roots[last_root_set].r_tmp;
319: for (i = 0; i < n_root_sets; i++) {
320: if (p >= GC_static_roots[i].r_start
321: && p < GC_static_roots[i].r_end) {
322: last_root_set = i;
323: return GC_static_roots[i].r_tmp;
324: }
325: }
326: return(FALSE);
327: }
328: #endif /* MSWIN32 || _WIN32_WCE_EMULATION */
329:
1.1 noro 330: ptr_t GC_approx_sp()
331: {
332: word dummy;
1.4 noro 333:
334: # ifdef _MSC_VER
335: # pragma warning(disable:4172)
336: # endif
1.1 noro 337: return((ptr_t)(&dummy));
1.4 noro 338: # ifdef _MSC_VER
339: # pragma warning(default:4172)
340: # endif
1.1 noro 341: }
342:
343: /*
344: * Data structure for excluded static roots.
345: * Real declaration is in gc_priv.h.
346:
347: struct exclusion {
348: ptr_t e_start;
349: ptr_t e_end;
350: };
351:
352: struct exclusion GC_excl_table[MAX_EXCLUSIONS];
353: -- Array of exclusions, ascending
354: -- address order.
355: */
356:
357: size_t GC_excl_table_entries = 0; /* Number of entries in use. */
358:
359: /* Return the first exclusion range that includes an address >= start_addr */
360: /* Assumes the exclusion table contains at least one entry (namely the */
361: /* GC data structures). */
362: struct exclusion * GC_next_exclusion(start_addr)
363: ptr_t start_addr;
364: {
365: size_t low = 0;
366: size_t high = GC_excl_table_entries - 1;
367: size_t mid;
368:
369: while (high > low) {
370: mid = (low + high) >> 1;
371: /* low <= mid < high */
372: if ((word) GC_excl_table[mid].e_end <= (word) start_addr) {
373: low = mid + 1;
374: } else {
375: high = mid;
376: }
377: }
378: if ((word) GC_excl_table[low].e_end <= (word) start_addr) return 0;
379: return GC_excl_table + low;
380: }
381:
382: void GC_exclude_static_roots(start, finish)
383: GC_PTR start;
384: GC_PTR finish;
385: {
386: struct exclusion * next;
387: size_t next_index, i;
388:
389: if (0 == GC_excl_table_entries) {
390: next = 0;
391: } else {
392: next = GC_next_exclusion(start);
393: }
394: if (0 != next) {
395: if ((word)(next -> e_start) < (word) finish) {
396: /* incomplete error check. */
397: ABORT("exclusion ranges overlap");
398: }
399: if ((word)(next -> e_start) == (word) finish) {
400: /* extend old range backwards */
401: next -> e_start = (ptr_t)start;
402: return;
403: }
404: next_index = next - GC_excl_table;
405: for (i = GC_excl_table_entries; i > next_index; --i) {
406: GC_excl_table[i] = GC_excl_table[i-1];
407: }
408: } else {
409: next_index = GC_excl_table_entries;
410: }
411: if (GC_excl_table_entries == MAX_EXCLUSIONS) ABORT("Too many exclusions");
412: GC_excl_table[next_index].e_start = (ptr_t)start;
413: GC_excl_table[next_index].e_end = (ptr_t)finish;
414: ++GC_excl_table_entries;
415: }
416:
417: /* Invoke push_conditional on ranges that are not excluded. */
418: void GC_push_conditional_with_exclusions(bottom, top, all)
419: ptr_t bottom;
420: ptr_t top;
421: int all;
422: {
423: struct exclusion * next;
424: ptr_t excl_start;
425:
426: while (bottom < top) {
427: next = GC_next_exclusion(bottom);
428: if (0 == next || (excl_start = next -> e_start) >= top) {
429: GC_push_conditional(bottom, top, all);
430: return;
431: }
432: if (excl_start > bottom) GC_push_conditional(bottom, excl_start, all);
433: bottom = next -> e_end;
434: }
435: }
436:
437: /*
438: * In the absence of threads, push the stack contents.
439: * In the presence of threads, push enough of the current stack
440: * to ensure that callee-save registers saved in collector frames have been
441: * seen.
442: */
443: void GC_push_current_stack(cold_gc_frame)
444: ptr_t cold_gc_frame;
445: {
446: # if defined(THREADS)
447: if (0 == cold_gc_frame) return;
448: # ifdef STACK_GROWS_DOWN
449: GC_push_all_eager(GC_approx_sp(), cold_gc_frame);
1.3 noro 450: /* For IA64, the register stack backing store is handled */
451: /* in the thread-specific code. */
1.1 noro 452: # else
453: GC_push_all_eager( cold_gc_frame, GC_approx_sp() );
454: # endif
455: # else
456: # ifdef STACK_GROWS_DOWN
457: GC_push_all_stack_partially_eager( GC_approx_sp(), GC_stackbottom,
458: cold_gc_frame );
1.2 noro 459: # ifdef IA64
460: /* We also need to push the register stack backing store. */
461: /* This should really be done in the same way as the */
462: /* regular stack. For now we fudge it a bit. */
463: /* Note that the backing store grows up, so we can't use */
464: /* GC_push_all_stack_partially_eager. */
465: {
466: extern word GC_save_regs_ret_val;
467: /* Previously set to backing store pointer. */
468: ptr_t bsp = (ptr_t) GC_save_regs_ret_val;
469: ptr_t cold_gc_bs_pointer;
1.4 noro 470: if (GC_all_interior_pointers) {
1.2 noro 471: cold_gc_bs_pointer = bsp - 2048;
472: if (cold_gc_bs_pointer < BACKING_STORE_BASE) {
473: cold_gc_bs_pointer = BACKING_STORE_BASE;
1.6 ! noro 474: } else {
! 475: GC_push_all_stack(BACKING_STORE_BASE, cold_gc_bs_pointer);
1.2 noro 476: }
1.4 noro 477: } else {
1.2 noro 478: cold_gc_bs_pointer = BACKING_STORE_BASE;
1.4 noro 479: }
1.2 noro 480: GC_push_all_eager(cold_gc_bs_pointer, bsp);
481: /* All values should be sufficiently aligned that we */
482: /* dont have to worry about the boundary. */
483: }
484: # endif
1.1 noro 485: # else
486: GC_push_all_stack_partially_eager( GC_stackbottom, GC_approx_sp(),
487: cold_gc_frame );
488: # endif
489: # endif /* !THREADS */
490: }
491:
492: /*
1.4 noro 493: * Push GC internal roots. Only called if there is some reason to believe
494: * these would not otherwise get registered.
495: */
496: void GC_push_gc_structures GC_PROTO((void))
497: {
498: GC_push_finalizer_structures();
499: GC_push_stubborn_structures();
500: # if defined(THREADS)
501: GC_push_thread_structures();
502: # endif
503: }
504:
1.6 ! noro 505: #ifdef THREAD_LOCAL_ALLOC
! 506: void GC_mark_thread_local_free_lists();
! 507: #endif
! 508:
1.4 noro 509: /*
1.1 noro 510: * Call the mark routines (GC_tl_push for a single pointer, GC_push_conditional
511: * on groups of pointers) on every top level accessible pointer.
512: * If all is FALSE, arrange to push only possibly altered values.
513: * Cold_gc_frame is an address inside a GC frame that
514: * remains valid until all marking is complete.
515: * A zero value indicates that it's OK to miss some
516: * register values.
517: */
518: void GC_push_roots(all, cold_gc_frame)
519: GC_bool all;
520: ptr_t cold_gc_frame;
521: {
522: register int i;
523:
524: /*
525: * Next push static data. This must happen early on, since it's
526: * not robust against mark stack overflow.
527: */
528: /* Reregister dynamic libraries, in case one got added. */
1.4 noro 529: # if (defined(DYNAMIC_LOADING) || defined(MSWIN32) || defined(MSWINCE) \
530: || defined(PCR)) && !defined(SRC_M3)
1.1 noro 531: GC_remove_tmp_roots();
1.4 noro 532: if (!GC_no_dls) GC_register_dynamic_libraries();
533: # else
534: GC_no_dls = TRUE;
1.1 noro 535: # endif
1.4 noro 536:
1.1 noro 537: /* Mark everything in static data areas */
538: for (i = 0; i < n_root_sets; i++) {
539: GC_push_conditional_with_exclusions(
540: GC_static_roots[i].r_start,
541: GC_static_roots[i].r_end, all);
1.4 noro 542: }
543:
544: /* Mark from GC internal roots if those might otherwise have */
545: /* been excluded. */
546: if (GC_no_dls || roots_were_cleared) {
547: GC_push_gc_structures();
1.1 noro 548: }
549:
1.6 ! noro 550: /* Mark thread local free lists, even if their mark */
! 551: /* descriptor excludes the link field. */
! 552: # ifdef THREAD_LOCAL_ALLOC
! 553: GC_mark_thread_local_free_lists();
! 554: # endif
! 555:
1.1 noro 556: /*
1.6 ! noro 557: * Now traverse stacks, and mark from register contents.
! 558: * These must be done last, since they can legitimately overflow
! 559: * the mark stack.
1.1 noro 560: */
1.6 ! noro 561: # ifdef USE_GENERIC_PUSH_REGS
! 562: GC_generic_push_regs(cold_gc_frame);
! 563: /* Also pushes stack, so that we catch callee-save registers */
! 564: /* saved inside the GC_push_regs frame. */
! 565: # else
! 566: /*
! 567: * push registers - i.e., call GC_push_one(r) for each
! 568: * register contents r.
! 569: */
! 570: GC_push_regs(); /* usually defined in machine_dep.c */
1.1 noro 571: GC_push_current_stack(cold_gc_frame);
1.6 ! noro 572: /* In the threads case, this only pushes collector frames. */
! 573: /* In the case of linux threads on IA64, the hot section of */
1.3 noro 574: /* the main stack is marked here, but the register stack */
575: /* backing store is handled in the threads-specific code. */
1.1 noro 576: # endif
577: if (GC_push_other_roots != 0) (*GC_push_other_roots)();
578: /* In the threads case, this also pushes thread stacks. */
1.6 ! noro 579: /* Note that without interior pointer recognition lots */
! 580: /* of stuff may have been pushed already, and this */
! 581: /* should be careful about mark stack overflows. */
1.1 noro 582: }
583:
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