263 lines
6.7 KiB
C
263 lines
6.7 KiB
C
/*
|
|
* Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
|
|
* Copyright (c) 1991-1994 by Xerox Corporation. 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.
|
|
*
|
|
* This file contains the functions:
|
|
* ptr_t GC_build_flXXX(h, old_fl)
|
|
* void GC_new_hblk(n)
|
|
*/
|
|
/* Boehm, May 19, 1994 2:09 pm PDT */
|
|
|
|
|
|
# include <stdio.h>
|
|
# include "private/gc_priv.h"
|
|
|
|
#ifndef SMALL_CONFIG
|
|
/*
|
|
* Build a free list for size 1 objects inside hblk h. Set the last link to
|
|
* be ofl. Return a pointer tpo the first free list entry.
|
|
*/
|
|
ptr_t GC_build_fl1(h, ofl)
|
|
struct hblk *h;
|
|
ptr_t ofl;
|
|
{
|
|
register word * p = h -> hb_body;
|
|
register word * lim = (word *)(h + 1);
|
|
|
|
p[0] = (word)ofl;
|
|
p[1] = (word)(p);
|
|
p[2] = (word)(p+1);
|
|
p[3] = (word)(p+2);
|
|
p += 4;
|
|
for (; p < lim; p += 4) {
|
|
p[0] = (word)(p-1);
|
|
p[1] = (word)(p);
|
|
p[2] = (word)(p+1);
|
|
p[3] = (word)(p+2);
|
|
};
|
|
return((ptr_t)(p-1));
|
|
}
|
|
|
|
/* The same for size 2 cleared objects */
|
|
ptr_t GC_build_fl_clear2(h, ofl)
|
|
struct hblk *h;
|
|
ptr_t ofl;
|
|
{
|
|
register word * p = h -> hb_body;
|
|
register word * lim = (word *)(h + 1);
|
|
|
|
p[0] = (word)ofl;
|
|
p[1] = 0;
|
|
p[2] = (word)p;
|
|
p[3] = 0;
|
|
p += 4;
|
|
for (; p < lim; p += 4) {
|
|
p[0] = (word)(p-2);
|
|
p[1] = 0;
|
|
p[2] = (word)p;
|
|
p[3] = 0;
|
|
};
|
|
return((ptr_t)(p-2));
|
|
}
|
|
|
|
/* The same for size 3 cleared objects */
|
|
ptr_t GC_build_fl_clear3(h, ofl)
|
|
struct hblk *h;
|
|
ptr_t ofl;
|
|
{
|
|
register word * p = h -> hb_body;
|
|
register word * lim = (word *)(h + 1) - 2;
|
|
|
|
p[0] = (word)ofl;
|
|
p[1] = 0;
|
|
p[2] = 0;
|
|
p += 3;
|
|
for (; p < lim; p += 3) {
|
|
p[0] = (word)(p-3);
|
|
p[1] = 0;
|
|
p[2] = 0;
|
|
};
|
|
return((ptr_t)(p-3));
|
|
}
|
|
|
|
/* The same for size 4 cleared objects */
|
|
ptr_t GC_build_fl_clear4(h, ofl)
|
|
struct hblk *h;
|
|
ptr_t ofl;
|
|
{
|
|
register word * p = h -> hb_body;
|
|
register word * lim = (word *)(h + 1);
|
|
|
|
p[0] = (word)ofl;
|
|
p[1] = 0;
|
|
p[2] = 0;
|
|
p[3] = 0;
|
|
p += 4;
|
|
for (; p < lim; p += 4) {
|
|
PREFETCH_FOR_WRITE(p+64);
|
|
p[0] = (word)(p-4);
|
|
p[1] = 0;
|
|
CLEAR_DOUBLE(p+2);
|
|
};
|
|
return((ptr_t)(p-4));
|
|
}
|
|
|
|
/* The same for size 2 uncleared objects */
|
|
ptr_t GC_build_fl2(h, ofl)
|
|
struct hblk *h;
|
|
ptr_t ofl;
|
|
{
|
|
register word * p = h -> hb_body;
|
|
register word * lim = (word *)(h + 1);
|
|
|
|
p[0] = (word)ofl;
|
|
p[2] = (word)p;
|
|
p += 4;
|
|
for (; p < lim; p += 4) {
|
|
p[0] = (word)(p-2);
|
|
p[2] = (word)p;
|
|
};
|
|
return((ptr_t)(p-2));
|
|
}
|
|
|
|
/* The same for size 4 uncleared objects */
|
|
ptr_t GC_build_fl4(h, ofl)
|
|
struct hblk *h;
|
|
ptr_t ofl;
|
|
{
|
|
register word * p = h -> hb_body;
|
|
register word * lim = (word *)(h + 1);
|
|
|
|
p[0] = (word)ofl;
|
|
p[4] = (word)p;
|
|
p += 8;
|
|
for (; p < lim; p += 8) {
|
|
PREFETCH_FOR_WRITE(p+64);
|
|
p[0] = (word)(p-4);
|
|
p[4] = (word)p;
|
|
};
|
|
return((ptr_t)(p-4));
|
|
}
|
|
|
|
#endif /* !SMALL_CONFIG */
|
|
|
|
|
|
/* Build a free list for objects of size sz inside heap block h. */
|
|
/* Clear objects inside h if clear is set. Add list to the end of */
|
|
/* the free list we build. Return the new free list. */
|
|
/* This could be called without the main GC lock, if we ensure that */
|
|
/* there is no concurrent collection which might reclaim objects that */
|
|
/* we have not yet allocated. */
|
|
ptr_t GC_build_fl(h, sz, clear, list)
|
|
struct hblk *h;
|
|
word sz;
|
|
GC_bool clear;
|
|
ptr_t list;
|
|
{
|
|
word *p, *prev;
|
|
word *last_object; /* points to last object in new hblk */
|
|
|
|
/* Do a few prefetches here, just because its cheap. */
|
|
/* If we were more serious about it, these should go inside */
|
|
/* the loops. But write prefetches usually don't seem to */
|
|
/* matter much. */
|
|
PREFETCH_FOR_WRITE((char *)h);
|
|
PREFETCH_FOR_WRITE((char *)h + 128);
|
|
PREFETCH_FOR_WRITE((char *)h + 256);
|
|
PREFETCH_FOR_WRITE((char *)h + 378);
|
|
/* Handle small objects sizes more efficiently. For larger objects */
|
|
/* the difference is less significant. */
|
|
# ifndef SMALL_CONFIG
|
|
switch (sz) {
|
|
case 1: return GC_build_fl1(h, list);
|
|
case 2: if (clear) {
|
|
return GC_build_fl_clear2(h, list);
|
|
} else {
|
|
return GC_build_fl2(h, list);
|
|
}
|
|
case 3: if (clear) {
|
|
return GC_build_fl_clear3(h, list);
|
|
} else {
|
|
/* It's messy to do better than the default here. */
|
|
break;
|
|
}
|
|
case 4: if (clear) {
|
|
return GC_build_fl_clear4(h, list);
|
|
} else {
|
|
return GC_build_fl4(h, list);
|
|
}
|
|
default:
|
|
break;
|
|
}
|
|
# endif /* !SMALL_CONFIG */
|
|
|
|
/* Clear the page if necessary. */
|
|
if (clear) BZERO(h, HBLKSIZE);
|
|
|
|
/* Add objects to free list */
|
|
p = &(h -> hb_body[sz]); /* second object in *h */
|
|
prev = &(h -> hb_body[0]); /* One object behind p */
|
|
last_object = (word *)((char *)h + HBLKSIZE);
|
|
last_object -= sz;
|
|
/* Last place for last object to start */
|
|
|
|
/* make a list of all objects in *h with head as last object */
|
|
while (p <= last_object) {
|
|
/* current object's link points to last object */
|
|
obj_link(p) = (ptr_t)prev;
|
|
prev = p;
|
|
p += sz;
|
|
}
|
|
p -= sz; /* p now points to last object */
|
|
|
|
/*
|
|
* put p (which is now head of list of objects in *h) as first
|
|
* pointer in the appropriate free list for this size.
|
|
*/
|
|
obj_link(h -> hb_body) = list;
|
|
return ((ptr_t)p);
|
|
}
|
|
|
|
/*
|
|
* Allocate a new heapblock for small objects of size n.
|
|
* Add all of the heapblock's objects to the free list for objects
|
|
* of that size.
|
|
* Set all mark bits if objects are uncollectable.
|
|
* Will fail to do anything if we are out of memory.
|
|
*/
|
|
void GC_new_hblk(sz, kind)
|
|
register word sz;
|
|
int kind;
|
|
{
|
|
register struct hblk *h; /* the new heap block */
|
|
register GC_bool clear = GC_obj_kinds[kind].ok_init;
|
|
|
|
# ifdef PRINTSTATS
|
|
if ((sizeof (struct hblk)) > HBLKSIZE) {
|
|
ABORT("HBLK SZ inconsistency");
|
|
}
|
|
# endif
|
|
|
|
/* Allocate a new heap block */
|
|
h = GC_allochblk(sz, kind, 0);
|
|
if (h == 0) return;
|
|
|
|
/* Mark all objects if appropriate. */
|
|
if (IS_UNCOLLECTABLE(kind)) GC_set_hdr_marks(HDR(h));
|
|
|
|
/* Build the free list */
|
|
GC_obj_kinds[kind].ok_freelist[sz] =
|
|
GC_build_fl(h, sz, clear, GC_obj_kinds[kind].ok_freelist[sz]);
|
|
}
|
|
|