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/*

 * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers

 * Copyright (c) 1991-1994 by Xerox Corporation.  All rights reserved.

 * Copyright (c) 1996 by Silicon Graphics.  All rights reserved.

 * Copyright (c) 2000 by Hewlett-Packard Company.  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.

 */

/*

 * These are extra allocation routines which are likely to be less

 * frequently used than those in malloc.c.  They are separate in the

 * hope that the .o file will be excluded from statically linked

 * executables.  We should probably break this up further.

 */

#include <stdio.h>

#include "private/gc_priv.h"

extern ptr_t GC_clear_stack();  /* in misc.c, behaves like identity */

void GC_extend_size_map();      /* in misc.c. */

GC_bool GC_alloc_reclaim_list();        /* in malloc.c */

/* Some externally visible but unadvertised variables to allow access to */

/* free lists from inlined allocators without including gc_priv.h        */

/* or introducing dependencies on internal data structure layouts.       */

ptr_t * GC_CONST GC_objfreelist_ptr = GC_objfreelist;

ptr_t * GC_CONST GC_aobjfreelist_ptr = GC_aobjfreelist;

ptr_t * GC_CONST GC_uobjfreelist_ptr = GC_uobjfreelist;

# ifdef ATOMIC_UNCOLLECTABLE

    ptr_t * GC_CONST GC_auobjfreelist_ptr = GC_auobjfreelist;

# endif

GC_PTR GC_generic_or_special_malloc(lb,knd)

word lb;

int knd;

{

    switch(knd) {

#     ifdef STUBBORN_ALLOC

        case STUBBORN:

            return(GC_malloc_stubborn((size_t)lb));

#     endif

        case PTRFREE:

            return(GC_malloc_atomic((size_t)lb));

        case NORMAL:

            return(GC_malloc((size_t)lb));

        case UNCOLLECTABLE:

            return(GC_malloc_uncollectable((size_t)lb));

#       ifdef ATOMIC_UNCOLLECTABLE

          case AUNCOLLECTABLE:

            return(GC_malloc_atomic_uncollectable((size_t)lb));

#       endif /* ATOMIC_UNCOLLECTABLE */

        default:

            return(GC_generic_malloc(lb,knd));

    }

}

/* Change the size of the block pointed to by p to contain at least   */

/* lb bytes.  The object may be (and quite likely will be) moved.     */

/* The kind (e.g. atomic) is the same as that of the old.             */

/* Shrinking of large blocks is not implemented well.                 */

# ifdef __STDC__

    GC_PTR GC_realloc(GC_PTR p, size_t lb)

# else

    GC_PTR GC_realloc(p,lb)

    GC_PTR p;

    size_t lb;

# endif

{

register struct hblk * h;

register hdr * hhdr;

register word sz;        /* Current size in bytes       */

register word orig_sz;   /* Original sz in bytes        */

int obj_kind;

    if (p == 0) return(GC_malloc(lb));   /* Required by ANSI */

    h = HBLKPTR(p);

    hhdr = HDR(h);

    sz = hhdr -> hb_sz;

    obj_kind = hhdr -> hb_obj_kind;

    sz = WORDS_TO_BYTES(sz);

    orig_sz = sz;

    if (sz > MAXOBJBYTES) {

        /* Round it up to the next whole heap block */

          register word descr;

          sz = (sz+HBLKSIZE-1) & (~HBLKMASK);

          hhdr -> hb_sz = BYTES_TO_WORDS(sz);

          descr = GC_obj_kinds[obj_kind].ok_descriptor;

          if (GC_obj_kinds[obj_kind].ok_relocate_descr) descr += sz;

          hhdr -> hb_descr = descr;

          if (IS_UNCOLLECTABLE(obj_kind)) GC_non_gc_bytes += (sz - orig_sz);

          /* Extra area is already cleared by GC_alloc_large_and_clear. */

    }

    if (ADD_SLOP(lb) <= sz) {

        if (lb >= (sz >> 1)) {

#           ifdef STUBBORN_ALLOC

                if (obj_kind == STUBBORN) GC_change_stubborn(p);

#           endif

            if (orig_sz > lb) {

              /* Clear unneeded part of object to avoid bogus pointer */

              /* tracing.                                             */

              /* Safe for stubborn objects.                           */

                BZERO(((ptr_t)p) + lb, orig_sz - lb);

            }

            return(p);

        } else {

            /* shrink */

              GC_PTR result =

                        GC_generic_or_special_malloc((word)lb, obj_kind);

              if (result == 0) return(0);

                  /* Could also return original object.  But this       */

                  /* gives the client warning of imminent disaster.     */

              BCOPY(p, result, lb);

#             ifndef IGNORE_FREE

                GC_free(p);

#             endif

              return(result);

        }

    } else {

        /* grow */

          GC_PTR result =

                GC_generic_or_special_malloc((word)lb, obj_kind);

          if (result == 0) return(0);

          BCOPY(p, result, sz);

#         ifndef IGNORE_FREE

            GC_free(p);

#         endif

          return(result);

    }

}

# if defined(REDIRECT_MALLOC) && !defined(REDIRECT_REALLOC)

#   define REDIRECT_REALLOC GC_realloc

# endif

# ifdef REDIRECT_REALLOC

/* As with malloc, avoid two levels of extra calls here.        */

# ifdef GC_ADD_CALLER

#   define RA GC_RETURN_ADDR,

# else

#   define RA

# endif

# define GC_debug_realloc_replacement(p, lb) \

        GC_debug_realloc(p, lb, RA "unknown", 0)

# ifdef __STDC__

    GC_PTR realloc(GC_PTR p, size_t lb)

# else

    GC_PTR realloc(p,lb)

    GC_PTR p;

    size_t lb;

# endif

  {

    return(REDIRECT_REALLOC(p, lb));

  }

# undef GC_debug_realloc_replacement

# endif /* REDIRECT_REALLOC */

/* The same thing, except caller does not hold allocation lock. */

/* We avoid holding allocation lock while we clear memory.      */

ptr_t GC_generic_malloc_ignore_off_page(lb, k)

register size_t lb;

register int k;

{

    register ptr_t result;

    word lw;

    word n_blocks;

    GC_bool init;

    DCL_LOCK_STATE;

    if (SMALL_OBJ(lb))

        return(GC_generic_malloc((word)lb, k));

    lw = ROUNDED_UP_WORDS(lb);

    n_blocks = OBJ_SZ_TO_BLOCKS(lw);

    init = GC_obj_kinds[k].ok_init;

    if (GC_have_errors) GC_print_all_errors();

    GC_INVOKE_FINALIZERS();

    DISABLE_SIGNALS();

    LOCK();

    result = (ptr_t)GC_alloc_large(lw, k, IGNORE_OFF_PAGE);

    if (0 != result) {

        if (GC_debugging_started) {

            BZERO(result, n_blocks * HBLKSIZE);

        } else {

#           ifdef THREADS

              /* Clear any memory that might be used for GC descriptors */

              /* before we release the lock.                          */

                ((word *)result)[0] = 0;

                ((word *)result)[1] = 0;

                ((word *)result)[lw-1] = 0;

                ((word *)result)[lw-2] = 0;

#           endif

        }

    }

    GC_words_allocd += lw;

    UNLOCK();

    ENABLE_SIGNALS();

    if (0 == result) {

        return((*GC_oom_fn)(lb));

    } else {

        if (init && !GC_debugging_started) {

            BZERO(result, n_blocks * HBLKSIZE);

        }

        return(result);

    }

}

# if defined(__STDC__) || defined(__cplusplus)

  void * GC_malloc_ignore_off_page(size_t lb)

# else

  char * GC_malloc_ignore_off_page(lb)

  register size_t lb;

# endif

{

    return((GC_PTR)GC_generic_malloc_ignore_off_page(lb, NORMAL));

}

# if defined(__STDC__) || defined(__cplusplus)

  void * GC_malloc_atomic_ignore_off_page(size_t lb)

# else

  char * GC_malloc_atomic_ignore_off_page(lb)

  register size_t lb;

# endif

{

    return((GC_PTR)GC_generic_malloc_ignore_off_page(lb, PTRFREE));

}

/* Increment GC_words_allocd from code that doesn't have direct access  */

/* to GC_arrays.                                                        */

# ifdef __STDC__

void GC_incr_words_allocd(size_t n)

{

    GC_words_allocd += n;

}

/* The same for GC_mem_freed.                           */

void GC_incr_mem_freed(size_t n)

{

    GC_mem_freed += n;

}

# endif /* __STDC__ */

/* Analogous to the above, but assumes a small object size, and         */

/* bypasses MERGE_SIZES mechanism.  Used by gc_inline.h.                */

ptr_t GC_generic_malloc_words_small_inner(lw, k)

register word lw;

register int k;

{

register ptr_t op;

register ptr_t *opp;

register struct obj_kind * kind = GC_obj_kinds + k;

    opp = &(kind -> ok_freelist[lw]);

    if( (op = *opp) == 0 ) {

        if (!GC_is_initialized) {

            GC_init_inner();

        }

        if (kind -> ok_reclaim_list != 0 || GC_alloc_reclaim_list(kind)) {

            op = GC_clear_stack(GC_allocobj((word)lw, k));

        }

        if (op == 0) {

            UNLOCK();

            ENABLE_SIGNALS();

            return ((*GC_oom_fn)(WORDS_TO_BYTES(lw)));

        }

    }

    *opp = obj_link(op);

    obj_link(op) = 0;

    GC_words_allocd += lw;

    return((ptr_t)op);

}

/* Analogous to the above, but assumes a small object size, and         */

/* bypasses MERGE_SIZES mechanism.  Used by gc_inline.h.                */

#ifdef __STDC__

     ptr_t GC_generic_malloc_words_small(size_t lw, int k)

#else 

     ptr_t GC_generic_malloc_words_small(lw, k)

     register word lw;

     register int k;

#endif

{

register ptr_t op;

DCL_LOCK_STATE;

    if (GC_have_errors) GC_print_all_errors();

    GC_INVOKE_FINALIZERS();

    DISABLE_SIGNALS();

    LOCK();

    op = GC_generic_malloc_words_small_inner(lw, k);

    UNLOCK();

    ENABLE_SIGNALS();

    return((ptr_t)op);

}

#if defined(THREADS) && !defined(SRC_M3)

extern signed_word GC_mem_found;   /* Protected by GC lock.  */

#ifdef PARALLEL_MARK

volatile signed_word GC_words_allocd_tmp = 0;

                        /* Number of words of memory allocated since    */

                        /* we released the GC lock.  Instead of         */

                        /* reacquiring the GC lock just to add this in, */

                        /* we add it in the next time we reacquire      */

                        /* the lock.  (Atomically adding it doesn't     */

                        /* work, since we would have to atomically      */

                        /* update it in GC_malloc, which is too         */

                        /* expensive.                                   */

#endif /* PARALLEL_MARK */

/* See reclaim.c: */

extern ptr_t GC_reclaim_generic();

/* Return a list of 1 or more objects of the indicated size, linked     */

/* through the first word in the object.  This has the advantage that   */

/* it acquires the allocation lock only once, and may greatly reduce    */

/* time wasted contending for the allocation lock.  Typical usage would */

/* be in a thread that requires many items of the same size.  It would  */

/* keep its own free list in thread-local storage, and call             */

/* GC_malloc_many or friends to replenish it.  (We do not round up      */

/* object sizes, since a call indicates the intention to consume many   */

/* objects of exactly this size.)                                       */

/* We return the free-list by assigning it to *result, since it is      */

/* not safe to return, e.g. a linked list of pointer-free objects,      */

/* since the collector would not retain the entire list if it were      */

/* invoked just as we were returning.                                   */

/* Note that the client should usually clear the link field.            */

void GC_generic_malloc_many(lb, k, result)

register word lb;

register int k;

ptr_t *result;

{

ptr_t op;

ptr_t p;

ptr_t *opp;

word lw;

word my_words_allocd = 0;

struct obj_kind * ok = &(GC_obj_kinds[k]);

DCL_LOCK_STATE;

#   if defined(GATHERSTATS) || defined(PARALLEL_MARK)

#     define COUNT_ARG , &my_words_allocd

#   else

#     define COUNT_ARG

#     define NEED_TO_COUNT

#   endif

    if (!SMALL_OBJ(lb)) {

        op = GC_generic_malloc(lb, k);

        if(0 != op) obj_link(op) = 0;

        *result = op;

        return;

    }

    lw = ALIGNED_WORDS(lb);

    if (GC_have_errors) GC_print_all_errors();

    GC_INVOKE_FINALIZERS();

    DISABLE_SIGNALS();

    LOCK();

    if (!GC_is_initialized) GC_init_inner();

    /* Do our share of marking work */

      if (GC_incremental && !GC_dont_gc) {

        ENTER_GC();

        GC_collect_a_little_inner(1);

        EXIT_GC();

      }

    /* First see if we can reclaim a page of objects waiting to be */

    /* reclaimed.                                                  */

    {

        struct hblk ** rlh = ok -> ok_reclaim_list;

        struct hblk * hbp;

        hdr * hhdr;

        rlh += lw;

        while ((hbp = *rlh) != 0) {

            hhdr = HDR(hbp);

            *rlh = hhdr -> hb_next;

            hhdr -> hb_last_reclaimed = (unsigned short) GC_gc_no;

#           ifdef PARALLEL_MARK

                {

                  signed_word my_words_allocd_tmp = GC_words_allocd_tmp;

                  GC_ASSERT(my_words_allocd_tmp >= 0);

                  /* We only decrement it while holding the GC lock.    */

                  /* Thus we can't accidentally adjust it down in more  */

                  /* than one thread simultaneously.                    */

                  if (my_words_allocd_tmp != 0) {

                    (void)GC_atomic_add(

                                (volatile GC_word *)(&GC_words_allocd_tmp),

                                (GC_word)(-my_words_allocd_tmp));

                    GC_words_allocd += my_words_allocd_tmp;

                  }

                }

                GC_acquire_mark_lock();

                ++ GC_fl_builder_count;

                UNLOCK();

                ENABLE_SIGNALS();

                GC_release_mark_lock();

#           endif

            op = GC_reclaim_generic(hbp, hhdr, lw,

                                    ok -> ok_init, 0 COUNT_ARG);

            if (op != 0) {

#             ifdef NEED_TO_COUNT

                /* We are neither gathering statistics, nor marking in  */

                /* parallel.  Thus GC_reclaim_generic doesn't count     */

                /* for us.                                              */

                for (p = op; p != 0; p = obj_link(p)) {

                  my_words_allocd += lw;

                }

#             endif

#             if defined(GATHERSTATS)

                /* We also reclaimed memory, so we need to adjust       */

                /* that count.                                          */

                /* This should be atomic, so the results may be         */

                /* inaccurate.                                          */

                GC_mem_found += my_words_allocd;

#             endif

#             ifdef PARALLEL_MARK

                *result = op;

                (void)GC_atomic_add(

                                (volatile GC_word *)(&GC_words_allocd_tmp),

                                (GC_word)(my_words_allocd));

                GC_acquire_mark_lock();

                -- GC_fl_builder_count;

                if (GC_fl_builder_count == 0) GC_notify_all_builder();

                GC_release_mark_lock();

                (void) GC_clear_stack(0);

                return;

#             else

                GC_words_allocd += my_words_allocd;

                goto out;

#             endif

            }

#           ifdef PARALLEL_MARK

              GC_acquire_mark_lock();

              -- GC_fl_builder_count;

              if (GC_fl_builder_count == 0) GC_notify_all_builder();

              GC_release_mark_lock();

              DISABLE_SIGNALS();

              LOCK();

              /* GC lock is needed for reclaim list access.     We      */

              /* must decrement fl_builder_count before reaquiring GC   */

              /* lock.  Hopefully this path is rare.                    */

#           endif

        }

    }

    /* Next try to use prefix of global free list if there is one.      */

    /* We don't refill it, but we need to use it up before allocating   */

    /* a new block ourselves.                                           */

      opp = &(GC_obj_kinds[k].ok_freelist[lw]);

      if ( (op = *opp) != 0 ) {

        *opp = 0;

        my_words_allocd = 0;

        for (p = op; p != 0; p = obj_link(p)) {

          my_words_allocd += lw;

          if (my_words_allocd >= BODY_SZ) {

            *opp = obj_link(p);

            obj_link(p) = 0;

            break;

          }

        }

        GC_words_allocd += my_words_allocd;

        goto out;

      }

    /* Next try to allocate a new block worth of objects of this size.  */

    {

        struct hblk *h = GC_allochblk(lw, k, 0);

        if (h != 0) {

          if (IS_UNCOLLECTABLE(k)) GC_set_hdr_marks(HDR(h));

          GC_words_allocd += BYTES_TO_WORDS(HBLKSIZE)

                               - BYTES_TO_WORDS(HBLKSIZE) % lw;

#         ifdef PARALLEL_MARK

            GC_acquire_mark_lock();

            ++ GC_fl_builder_count;

            UNLOCK();

            ENABLE_SIGNALS();

            GC_release_mark_lock();

#         endif

          op = GC_build_fl(h, lw, ok -> ok_init, 0);

#         ifdef PARALLEL_MARK

            *result = op;

            GC_acquire_mark_lock();

            -- GC_fl_builder_count;

            if (GC_fl_builder_count == 0) GC_notify_all_builder();

            GC_release_mark_lock();

            (void) GC_clear_stack(0);

            return;

#         else

            goto out;

#         endif

        }

    }

    /* As a last attempt, try allocating a single object.  Note that    */

    /* this may trigger a collection or expand the heap.                */

      op = GC_generic_malloc_inner(lb, k);

      if (0 != op) obj_link(op) = 0;

  out:

    *result = op;

    UNLOCK();

    ENABLE_SIGNALS();

    (void) GC_clear_stack(0);

}

GC_PTR GC_malloc_many(size_t lb)

{

    ptr_t result;

    GC_generic_malloc_many(lb, NORMAL, &result);

    return result;

}

/* Note that the "atomic" version of this would be unsafe, since the    */

/* links would not be seen by the collector.                            */

# endif

/* Allocate lb bytes of pointerful, traced, but not collectable data */

# ifdef __STDC__

    GC_PTR GC_malloc_uncollectable(size_t lb)

# else

    GC_PTR GC_malloc_uncollectable(lb)

    size_t lb;

# endif

{

register ptr_t op;

register ptr_t *opp;

register word lw;

DCL_LOCK_STATE;

    if( SMALL_OBJ(lb) ) {

#       ifdef MERGE_SIZES

          if (EXTRA_BYTES != 0 && lb != 0) lb--;

                  /* We don't need the extra byte, since this won't be  */

                  /* collected anyway.                                  */

          lw = GC_size_map[lb];

#       else

          lw = ALIGNED_WORDS(lb);

#       endif

        opp = &(GC_uobjfreelist[lw]);

        FASTLOCK();

        if( FASTLOCK_SUCCEEDED() && (op = *opp) != 0 ) {

            /* See above comment on signals.    */

            *opp = obj_link(op);

            obj_link(op) = 0;

            GC_words_allocd += lw;

            /* Mark bit ws already set on free list.  It will be        */

            /* cleared only temporarily during a collection, as a       */

            /* result of the normal free list mark bit clearing.        */

            GC_non_gc_bytes += WORDS_TO_BYTES(lw);

            FASTUNLOCK();

            return((GC_PTR) op);

        }

        FASTUNLOCK();

        op = (ptr_t)GC_generic_malloc((word)lb, UNCOLLECTABLE);

    } else {

        op = (ptr_t)GC_generic_malloc((word)lb, UNCOLLECTABLE);

    }

    if (0 == op) return(0);

    /* We don't need the lock here, since we have an undisguised        */

    /* pointer.  We do need to hold the lock while we adjust            */

    /* mark bits.                                                       */

    {

        register struct hblk * h;

        h = HBLKPTR(op);

        lw = HDR(h) -> hb_sz;

        DISABLE_SIGNALS();

        LOCK();

        GC_set_mark_bit(op);

        GC_non_gc_bytes += WORDS_TO_BYTES(lw);

        UNLOCK();

        ENABLE_SIGNALS();

        return((GC_PTR) op);

    }

}

#ifdef __STDC__

/* Not well tested nor integrated.      */

/* Debug version is tricky and currently missing.       */

#include <limits.h>

GC_PTR GC_memalign(size_t align, size_t lb)

{

    size_t new_lb;

    size_t offset;

    ptr_t result;

#   ifdef ALIGN_DOUBLE

        if (align <= WORDS_TO_BYTES(2) && lb > align) return GC_malloc(lb);

#   endif

    if (align <= WORDS_TO_BYTES(1)) return GC_malloc(lb);

    if (align >= HBLKSIZE/2 || lb >= HBLKSIZE/2) {

        if (align > HBLKSIZE) return GC_oom_fn(LONG_MAX-1024) /* Fail */;

        return GC_malloc(lb <= HBLKSIZE? HBLKSIZE : lb);

            /* Will be HBLKSIZE aligned.        */

    }

    /* We could also try to make sure that the real rounded-up object size */

    /* is a multiple of align.  That would be correct up to HBLKSIZE.      */

    new_lb = lb + align - 1;

    result = GC_malloc(new_lb);

    offset = (word)result % align;

    if (offset != 0) {

        offset = align - offset;

        if (!GC_all_interior_pointers) {

            if (offset >= VALID_OFFSET_SZ) return GC_malloc(HBLKSIZE);

            GC_register_displacement(offset);

        }

    }

    result = (GC_PTR) ((ptr_t)result + offset);

    GC_ASSERT((word)result % align == 0);

    return result;

}

#endif 

# ifdef ATOMIC_UNCOLLECTABLE

/* Allocate lb bytes of pointerfree, untraced, uncollectable data       */

/* This is normally roughly equivalent to the system malloc.            */

/* But it may be useful if malloc is redefined.                         */

# ifdef __STDC__

    GC_PTR GC_malloc_atomic_uncollectable(size_t lb)

# else

    GC_PTR GC_malloc_atomic_uncollectable(lb)

    size_t lb;

# endif

{

register ptr_t op;

register ptr_t *opp;

register word lw;

DCL_LOCK_STATE;

    if( SMALL_OBJ(lb) ) {

#       ifdef MERGE_SIZES

          if (EXTRA_BYTES != 0 && lb != 0) lb--;

                  /* We don't need the extra byte, since this won't be  */

                  /* collected anyway.                                  */

          lw = GC_size_map[lb];

#       else

          lw = ALIGNED_WORDS(lb);

#       endif

        opp = &(GC_auobjfreelist[lw]);

        FASTLOCK();

        if( FASTLOCK_SUCCEEDED() && (op = *opp) != 0 ) {

            /* See above comment on signals.    */

            *opp = obj_link(op);

            obj_link(op) = 0;

            GC_words_allocd += lw;

            /* Mark bit was already set while object was on free list. */

            GC_non_gc_bytes += WORDS_TO_BYTES(lw);

            FASTUNLOCK();

            return((GC_PTR) op);

        }

        FASTUNLOCK();

        op = (ptr_t)GC_generic_malloc((word)lb, AUNCOLLECTABLE);

    } else {

        op = (ptr_t)GC_generic_malloc((word)lb, AUNCOLLECTABLE);

    }

    if (0 == op) return(0);

    /* We don't need the lock here, since we have an undisguised        */

    /* pointer.  We do need to hold the lock while we adjust            */

    /* mark bits.                                                       */