/* * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers * Copyright (c) 1991-1995 by Xerox Corporation. All rights reserved. * Copyright (c) 1997 by Silicon Graphics. All rights reserved. * * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED * OR IMPLIED. ANY USE IS AT YOUR OWN RISK. * * Permission is hereby granted to use or copy this program * for any purpose, provided the above notices are retained on all copies. * Permission to modify the code and to distribute modified code is granted, * provided the above notices are retained, and a notice that the code was * modified is included with the above copyright notice. */ /* Boehm, October 9, 1995 1:16 pm PDT */ # include "gc_priv.h" void GC_default_print_heap_obj_proc(); GC_API void GC_register_finalizer_no_order GC_PROTO((GC_PTR obj, GC_finalization_proc fn, GC_PTR cd, GC_finalization_proc *ofn, GC_PTR *ocd)); /* Do we want to and know how to save the call stack at the time of */ /* an allocation? How much space do we want to use in each object? */ # define START_FLAG ((word)0xfedcedcb) # define END_FLAG ((word)0xbcdecdef) /* Stored both one past the end of user object, and one before */ /* the end of the object as seen by the allocator. */ /* Object header */ typedef struct { char * oh_string; /* object descriptor string */ word oh_int; /* object descriptor integers */ # ifdef NEED_CALLINFO struct callinfo oh_ci[NFRAMES]; # endif word oh_sz; /* Original malloc arg. */ word oh_sf; /* start flag */ } oh; /* The size of the above structure is assumed not to dealign things, */ /* and to be a multiple of the word length. */ #define DEBUG_BYTES (sizeof (oh) + sizeof (word)) #undef ROUNDED_UP_WORDS #define ROUNDED_UP_WORDS(n) BYTES_TO_WORDS((n) + WORDS_TO_BYTES(1) - 1) #ifdef SAVE_CALL_CHAIN # define ADD_CALL_CHAIN(base, ra) GC_save_callers(((oh *)(base)) -> oh_ci) # define PRINT_CALL_CHAIN(base) GC_print_callers(((oh *)(base)) -> oh_ci) #else # ifdef GC_ADD_CALLER # define ADD_CALL_CHAIN(base, ra) ((oh *)(base)) -> oh_ci[0].ci_pc = (ra) # define PRINT_CALL_CHAIN(base) GC_print_callers(((oh *)(base)) -> oh_ci) # else # define ADD_CALL_CHAIN(base, ra) # define PRINT_CALL_CHAIN(base) # endif #endif /* Check whether object with base pointer p has debugging info */ /* p is assumed to point to a legitimate object in our part */ /* of the heap. */ GC_bool GC_has_debug_info(p) ptr_t p; { register oh * ohdr = (oh *)p; register ptr_t body = (ptr_t)(ohdr + 1); register word sz = GC_size((ptr_t) ohdr); if (HBLKPTR((ptr_t)ohdr) != HBLKPTR((ptr_t)body) || sz < sizeof (oh)) { return(FALSE); } if (ohdr -> oh_sz == sz) { /* Object may have had debug info, but has been deallocated */ return(FALSE); } if (ohdr -> oh_sf == (START_FLAG ^ (word)body)) return(TRUE); if (((word *)ohdr)[BYTES_TO_WORDS(sz)-1] == (END_FLAG ^ (word)body)) { return(TRUE); } return(FALSE); } /* Store debugging info into p. Return displaced pointer. */ /* Assumes we don't hold allocation lock. */ ptr_t GC_store_debug_info(p, sz, string, integer) register ptr_t p; /* base pointer */ word sz; /* bytes */ char * string; word integer; { register oh * ohdr = (oh *)p; register word * result = (word *)(ohdr + 1); DCL_LOCK_STATE; /* There is some argument that we should dissble signals here. */ /* But that's expensive. And this way things should only appear */ /* inconsistent while we're in the handler. */ LOCK(); ohdr -> oh_string = string; ohdr -> oh_int = integer; ohdr -> oh_sz = sz; ohdr -> oh_sf = START_FLAG ^ (word)result; ((word *)p)[BYTES_TO_WORDS(GC_size(p))-1] = result[ROUNDED_UP_WORDS(sz)] = END_FLAG ^ (word)result; UNLOCK(); return((ptr_t)result); } /* Check the object with debugging info at p */ /* return NIL if it's OK. Else return clobbered */ /* address. */ ptr_t GC_check_annotated_obj(ohdr) register oh * ohdr; { register ptr_t body = (ptr_t)(ohdr + 1); register word gc_sz = GC_size((ptr_t)ohdr); if (ohdr -> oh_sz + DEBUG_BYTES > gc_sz) { return((ptr_t)(&(ohdr -> oh_sz))); } if (ohdr -> oh_sf != (START_FLAG ^ (word)body)) { return((ptr_t)(&(ohdr -> oh_sf))); } if (((word *)ohdr)[BYTES_TO_WORDS(gc_sz)-1] != (END_FLAG ^ (word)body)) { return((ptr_t)((word *)ohdr + BYTES_TO_WORDS(gc_sz)-1)); } if (((word *)body)[ROUNDED_UP_WORDS(ohdr -> oh_sz)] != (END_FLAG ^ (word)body)) { return((ptr_t)((word *)body + ROUNDED_UP_WORDS(ohdr -> oh_sz))); } return(0); } #ifdef MACOS extern const char* getTypeName(void* ptr); #else #define getTypeName(ptr) ("void*") #endif void GC_print_obj(p) ptr_t p; { register oh * ohdr = (oh *)GC_base(p); register word *wp, *wend; wp = (word*)((unsigned long)ohdr + sizeof(oh)); GC_err_printf3("0x%08lX <%s> (%ld)\n", wp, getTypeName(wp), (unsigned long)(ohdr -> oh_sz)); /* print all potential references held by this object. */ wend = (word*)((unsigned long)wp + ohdr -> oh_sz); while (wp < wend) GC_err_printf1("\t0x%08lX\n", *wp++); PRINT_CALL_CHAIN(ohdr); } #define NEXT_WORD(ohdr) (ohdr->oh_ci[1].ci_pc) #define NEXT_OBJECT(ohdr) (*(oh**)&ohdr->oh_ci[1].ci_pc) #define IS_PLAUSIBLE_POINTER(p) ((p >= GC_least_plausible_heap_addr) && (p < GC_greatest_plausible_heap_addr)) /** * Note: this can be made completely iterative, using the mark * field as a link to the next object to be scanned. */ void GC_trace_object(ptr_t p) { register oh *head, *scan, *tail; register word *wp, *wend; head = scan = tail = (oh *)GC_base(p); if (head == 0) return; /* invariant: end of list always marked with value 1. */ NEXT_WORD(tail) = 1; for (;;) { wp = (word*)((unsigned long)scan + sizeof(oh)); GC_err_printf3("\n0x%08lX <%s> (%ld)\n", wp, getTypeName(wp), (unsigned long)(scan->oh_sz)); /* print all potential references held by this object. */ wend = (word*)((unsigned long)wp + scan->oh_sz); while (wp < wend) { p = (ptr_t) *wp++; GC_err_printf1("\t0x%08lX\n", p); if (IS_PLAUSIBLE_POINTER(p)) { oh* header = (oh *)GC_base(p); if (header && !NEXT_WORD(header)) { NEXT_OBJECT(tail) = header; tail = header; NEXT_WORD(tail) = 1; } } } PRINT_CALL_CHAIN(scan); if (NEXT_WORD(scan) == 1) break; scan = NEXT_OBJECT(scan); } /* clear all marks. */ scan = head; NEXT_WORD(tail) = 0; while (scan) { tail = NEXT_OBJECT(scan); NEXT_WORD(scan) = 0; scan = tail; } } void GC_debug_print_heap_obj_proc(p) ptr_t p; { if (GC_has_debug_info(p)) { GC_print_obj(p); } else { GC_default_print_heap_obj_proc(p); } } void GC_print_smashed_obj(p, clobbered_addr) ptr_t p, clobbered_addr; { register oh * ohdr = (oh *)GC_base(p); GC_err_printf2("0x%lx in object at 0x%lx(", (unsigned long)clobbered_addr, (unsigned long)p); if (clobbered_addr <= (ptr_t)(&(ohdr -> oh_sz)) || ohdr -> oh_string == 0) { GC_err_printf1(", appr. sz = %ld)\n", (GC_size((ptr_t)ohdr) - DEBUG_BYTES)); } else { if (ohdr -> oh_string[0] == '\0') { GC_err_puts("EMPTY(smashed?)"); } else { GC_err_puts(ohdr -> oh_string); } GC_err_printf2(":%ld, sz=%ld)\n", (unsigned long)(ohdr -> oh_int), (unsigned long)(ohdr -> oh_sz)); PRINT_CALL_CHAIN(ohdr); } } void GC_check_heap_proc(); void GC_start_debugging() { GC_check_heap = GC_check_heap_proc; GC_print_heap_obj = GC_debug_print_heap_obj_proc; GC_debugging_started = TRUE; GC_register_displacement((word)sizeof(oh)); } # if defined(__STDC__) || defined(__cplusplus) void GC_debug_register_displacement(GC_word offset) # else void GC_debug_register_displacement(offset) GC_word offset; # endif { GC_register_displacement(offset); GC_register_displacement((word)sizeof(oh) + offset); } # ifdef GC_ADD_CALLER # define EXTRA_ARGS word ra, char * s, int i # define OPT_RA ra, # else # define EXTRA_ARGS char * s, int i # define OPT_RA # endif # ifdef __STDC__ GC_PTR GC_debug_malloc(size_t lb, EXTRA_ARGS) # else GC_PTR GC_debug_malloc(lb, s, i) size_t lb; char * s; int i; # ifdef GC_ADD_CALLER --> GC_ADD_CALLER not implemented for K&R C # endif # endif { GC_PTR result = GC_malloc(lb + DEBUG_BYTES); if (result == 0) { GC_err_printf1("GC_debug_malloc(%ld) returning NIL (", (unsigned long) lb); GC_err_puts(s); GC_err_printf1(":%ld)\n", (unsigned long)i); return(0); } if (!GC_debugging_started) { GC_start_debugging(); } ADD_CALL_CHAIN(result, ra); return (GC_store_debug_info(result, (word)lb, s, (word)i)); } #ifdef STUBBORN_ALLOC # ifdef __STDC__ GC_PTR GC_debug_malloc_stubborn(size_t lb, EXTRA_ARGS) # else GC_PTR GC_debug_malloc_stubborn(lb, s, i) size_t lb; char * s; int i; # endif { GC_PTR result = GC_malloc_stubborn(lb + DEBUG_BYTES); if (result == 0) { GC_err_printf1("GC_debug_malloc(%ld) returning NIL (", (unsigned long) lb); GC_err_puts(s); GC_err_printf1(":%ld)\n", (unsigned long)i); return(0); } if (!GC_debugging_started) { GC_start_debugging(); } ADD_CALL_CHAIN(result, ra); return (GC_store_debug_info(result, (word)lb, s, (word)i)); } void GC_debug_change_stubborn(p) GC_PTR p; { register GC_PTR q = GC_base(p); register hdr * hhdr; if (q == 0) { GC_err_printf1("Bad argument: 0x%lx to GC_debug_change_stubborn\n", (unsigned long) p); ABORT("GC_debug_change_stubborn: bad arg"); } hhdr = HDR(q); if (hhdr -> hb_obj_kind != STUBBORN) { GC_err_printf1("GC_debug_change_stubborn arg not stubborn: 0x%lx\n", (unsigned long) p); ABORT("GC_debug_change_stubborn: arg not stubborn"); } GC_change_stubborn(q); } void GC_debug_end_stubborn_change(p) GC_PTR p; { register GC_PTR q = GC_base(p); register hdr * hhdr; if (q == 0) { GC_err_printf1("Bad argument: 0x%lx to GC_debug_end_stubborn_change\n", (unsigned long) p); ABORT("GC_debug_end_stubborn_change: bad arg"); } hhdr = HDR(q); if (hhdr -> hb_obj_kind != STUBBORN) { GC_err_printf1("debug_end_stubborn_change arg not stubborn: 0x%lx\n", (unsigned long) p); ABORT("GC_debug_end_stubborn_change: arg not stubborn"); } GC_end_stubborn_change(q); } #endif /* STUBBORN_ALLOC */ # ifdef __STDC__ GC_PTR GC_debug_malloc_atomic(size_t lb, EXTRA_ARGS) # else GC_PTR GC_debug_malloc_atomic(lb, s, i) size_t lb; char * s; int i; # endif { GC_PTR result = GC_malloc_atomic(lb + DEBUG_BYTES); if (result == 0) { GC_err_printf1("GC_debug_malloc_atomic(%ld) returning NIL (", (unsigned long) lb); GC_err_puts(s); GC_err_printf1(":%ld)\n", (unsigned long)i); return(0); } if (!GC_debugging_started) { GC_start_debugging(); } ADD_CALL_CHAIN(result, ra); return (GC_store_debug_info(result, (word)lb, s, (word)i)); } # ifdef __STDC__ GC_PTR GC_debug_malloc_uncollectable(size_t lb, EXTRA_ARGS) # else GC_PTR GC_debug_malloc_uncollectable(lb, s, i) size_t lb; char * s; int i; # endif { GC_PTR result = GC_malloc_uncollectable(lb + DEBUG_BYTES); if (result == 0) { GC_err_printf1("GC_debug_malloc_uncollectable(%ld) returning NIL (", (unsigned long) lb); GC_err_puts(s); GC_err_printf1(":%ld)\n", (unsigned long)i); return(0); } if (!GC_debugging_started) { GC_start_debugging(); } ADD_CALL_CHAIN(result, ra); return (GC_store_debug_info(result, (word)lb, s, (word)i)); } #ifdef ATOMIC_UNCOLLECTABLE # ifdef __STDC__ GC_PTR GC_debug_malloc_atomic_uncollectable(size_t lb, EXTRA_ARGS) # else GC_PTR GC_debug_malloc_atomic_uncollectable(lb, s, i) size_t lb; char * s; int i; # endif { GC_PTR result = GC_malloc_atomic_uncollectable(lb + DEBUG_BYTES); if (result == 0) { GC_err_printf1( "GC_debug_malloc_atomic_uncollectable(%ld) returning NIL (", (unsigned long) lb); GC_err_puts(s); GC_err_printf1(":%ld)\n", (unsigned long)i); return(0); } if (!GC_debugging_started) { GC_start_debugging(); } ADD_CALL_CHAIN(result, ra); return (GC_store_debug_info(result, (word)lb, s, (word)i)); } #endif /* ATOMIC_UNCOLLECTABLE */ # ifdef __STDC__ void GC_debug_free(GC_PTR p) # else void GC_debug_free(p) GC_PTR p; # endif { register GC_PTR base = GC_base(p); register ptr_t clobbered; /* ignore free(NULL) */ if (p == 0) return; if (base == 0) { GC_err_printf1("Attempt to free invalid pointer %lx\n", (unsigned long)p); if (p != 0) ABORT("free(invalid pointer)"); } if ((ptr_t)p - (ptr_t)base != sizeof(oh)) { GC_err_printf1( "GC_debug_free called on pointer %lx wo debugging info\n", (unsigned long)p); } else { oh * ohdr = (oh *)base; clobbered = GC_check_annotated_obj(ohdr); if (clobbered != 0) { if (ohdr -> oh_sz == GC_size(base)) { GC_err_printf0( "GC_debug_free: found previously deallocated (?) object at "); } else { GC_err_printf0("GC_debug_free: found smashed object at "); } GC_print_smashed_obj(p, clobbered); } /* Invalidate size */ ohdr -> oh_sz = GC_size(base); } # ifdef FIND_LEAK GC_free(base); # else { register hdr * hhdr = HDR(p); GC_bool uncollectable = FALSE; if (hhdr -> hb_obj_kind == UNCOLLECTABLE) { uncollectable = TRUE; } # ifdef ATOMIC_UNCOLLECTABLE if (hhdr -> hb_obj_kind == AUNCOLLECTABLE) { uncollectable = TRUE; } # endif if (uncollectable) GC_free(base); } # endif } # ifdef __STDC__ GC_PTR GC_debug_realloc(GC_PTR p, size_t lb, EXTRA_ARGS) # else GC_PTR GC_debug_realloc(p, lb, s, i) GC_PTR p; size_t lb; char *s; int i; # endif { register GC_PTR base = GC_base(p); register ptr_t clobbered; register GC_PTR result; register size_t copy_sz = lb; register size_t old_sz; register hdr * hhdr; if (p == 0) return(GC_debug_malloc(lb, OPT_RA s, i)); if (base == 0) { GC_err_printf1( "Attempt to reallocate invalid pointer %lx\n", (unsigned long)p); ABORT("realloc(invalid pointer)"); } if ((ptr_t)p - (ptr_t)base != sizeof(oh)) { GC_err_printf1( "GC_debug_realloc called on pointer %lx wo debugging info\n", (unsigned long)p); return(GC_realloc(p, lb)); } hhdr = HDR(base); switch (hhdr -> hb_obj_kind) { # ifdef STUBBORN_ALLOC case STUBBORN: result = GC_debug_malloc_stubborn(lb, OPT_RA s, i); break; # endif case NORMAL: result = GC_debug_malloc(lb, OPT_RA s, i); break; case PTRFREE: result = GC_debug_malloc_atomic(lb, OPT_RA s, i); break; case UNCOLLECTABLE: result = GC_debug_malloc_uncollectable(lb, OPT_RA s, i); break; # ifdef ATOMIC_UNCOLLECTABLE case AUNCOLLECTABLE: result = GC_debug_malloc_atomic_uncollectable(lb, OPT_RA s, i); break; # endif default: GC_err_printf0("GC_debug_realloc: encountered bad kind\n"); ABORT("bad kind"); } clobbered = GC_check_annotated_obj((oh *)base); if (clobbered != 0) { GC_err_printf0("GC_debug_realloc: found smashed object at "); GC_print_smashed_obj(p, clobbered); } old_sz = ((oh *)base) -> oh_sz; if (old_sz < copy_sz) copy_sz = old_sz; if (result == 0) return(0); BCOPY(p, result, copy_sz); GC_debug_free(p); return(result); } /* Check all marked objects in the given block for validity */ /*ARGSUSED*/ void GC_check_heap_block(hbp, dummy) register struct hblk *hbp; /* ptr to current heap block */ word dummy; { register struct hblkhdr * hhdr = HDR(hbp); register word sz = hhdr -> hb_sz; register int word_no; register word *p, *plim; p = (word *)(hbp->hb_body); word_no = HDR_WORDS; if (sz > MAXOBJSZ) { plim = p; } else { plim = (word *)((((word)hbp) + HBLKSIZE) - WORDS_TO_BYTES(sz)); } /* go through all words in block */ while( p <= plim ) { if( mark_bit_from_hdr(hhdr, word_no) && GC_has_debug_info((ptr_t)p)) { ptr_t clobbered = GC_check_annotated_obj((oh *)p); if (clobbered != 0) { GC_err_printf0( "GC_check_heap_block: found smashed object at "); GC_print_smashed_obj((ptr_t)p, clobbered); } } word_no += sz; p += sz; } } /* This assumes that all accessible objects are marked, and that */ /* I hold the allocation lock. Normally called by collector. */ void GC_check_heap_proc() { # ifndef SMALL_CONFIG if (sizeof(oh) & (2 * sizeof(word) - 1) != 0) { ABORT("Alignment problem: object header has inappropriate size\n"); } # endif GC_apply_to_all_blocks(GC_check_heap_block, (word)0); } struct closure { GC_finalization_proc cl_fn; GC_PTR cl_data; }; # ifdef __STDC__ void * GC_make_closure(GC_finalization_proc fn, void * data) # else GC_PTR GC_make_closure(fn, data) GC_finalization_proc fn; GC_PTR data; # endif { struct closure * result = (struct closure *) GC_malloc(sizeof (struct closure)); result -> cl_fn = fn; result -> cl_data = data; return((GC_PTR)result); } # ifdef __STDC__ void GC_debug_invoke_finalizer(void * obj, void * data) # else void GC_debug_invoke_finalizer(obj, data) char * obj; char * data; # endif { register struct closure * cl = (struct closure *) data; (*(cl -> cl_fn))((GC_PTR)((char *)obj + sizeof(oh)), cl -> cl_data); } # ifdef __STDC__ void GC_debug_register_finalizer(GC_PTR obj, GC_finalization_proc fn, GC_PTR cd, GC_finalization_proc *ofn, GC_PTR *ocd) # else void GC_debug_register_finalizer(obj, fn, cd, ofn, ocd) GC_PTR obj; GC_finalization_proc fn; GC_PTR cd; GC_finalization_proc *ofn; GC_PTR *ocd; # endif { ptr_t base = GC_base(obj); if (0 == base || (ptr_t)obj - base != sizeof(oh)) { GC_err_printf1( "GC_register_finalizer called with non-base-pointer 0x%lx\n", obj); } GC_register_finalizer(base, GC_debug_invoke_finalizer, GC_make_closure(fn,cd), ofn, ocd); } # ifdef __STDC__ void GC_debug_register_finalizer_no_order (GC_PTR obj, GC_finalization_proc fn, GC_PTR cd, GC_finalization_proc *ofn, GC_PTR *ocd) # else void GC_debug_register_finalizer_no_order (obj, fn, cd, ofn, ocd) GC_PTR obj; GC_finalization_proc fn; GC_PTR cd; GC_finalization_proc *ofn; GC_PTR *ocd; # endif { ptr_t base = GC_base(obj); if (0 == base || (ptr_t)obj - base != sizeof(oh)) { GC_err_printf1( "GC_register_finalizer_no_order called with non-base-pointer 0x%lx\n", obj); } GC_register_finalizer_no_order(base, GC_debug_invoke_finalizer, GC_make_closure(fn,cd), ofn, ocd); } # ifdef __STDC__ void GC_debug_register_finalizer_ignore_self (GC_PTR obj, GC_finalization_proc fn, GC_PTR cd, GC_finalization_proc *ofn, GC_PTR *ocd) # else void GC_debug_register_finalizer_ignore_self (obj, fn, cd, ofn, ocd) GC_PTR obj; GC_finalization_proc fn; GC_PTR cd; GC_finalization_proc *ofn; GC_PTR *ocd; # endif { ptr_t base = GC_base(obj); if (0 == base || (ptr_t)obj - base != sizeof(oh)) { GC_err_printf1( "GC_register_finalizer_ignore_self called with non-base-pointer 0x%lx\n", obj); } GC_register_finalizer_ignore_self(base, GC_debug_invoke_finalizer, GC_make_closure(fn,cd), ofn, ocd); }