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#include <string.h>
#include "fail.h"
#include "freelist.h"
#include "gc.h"
#include "gc_ctrl.h"
#include "major_gc.h"
#include "memory.h"
#include "minor_gc.h"
#include "misc.h"
#include "mlvalues.h"
/* Allocate more memory from malloc for the heap.
Return a block of at least the requested size (in words).
Return NULL when out of memory.
*/
static char *expand_heap (request)
mlsize_t request;
{
char *mem;
char *new_page_table;
asize_t new_page_table_size;
asize_t malloc_request;
asize_t i, more_pages;
malloc_request = round_heap_chunk_size (Bhsize_wosize (request));
gc_message ("Growing heap to %ldk\n",
(stat_heap_size + malloc_request) / 1024);
mem = aligned_malloc (malloc_request + sizeof (heap_chunk_head),
sizeof (heap_chunk_head));
if (mem == NULL){
gc_message ("No room for growing heap\n", 0);
return NULL;
}
mem += sizeof (heap_chunk_head);
(((heap_chunk_head *) mem) [-1]).size = malloc_request;
Assert (Wosize_bhsize (malloc_request) >= request);
Hd_hp (mem) = Make_header (Wosize_bhsize (malloc_request), 0, Blue);
if (mem < heap_start){
more_pages = -Page (mem);
}else if (Page (mem + malloc_request) > page_table_size){
Assert (mem >= heap_end);
more_pages = Page (mem + malloc_request) - page_table_size;
}else{
more_pages = 0;
}
if (more_pages != 0){
new_page_table_size = page_table_size + more_pages;
new_page_table = (char *) malloc (new_page_table_size);
if (new_page_table == NULL){
gc_message ("No room for growing page table\n", 0);
free (mem);
return NULL;
}
} else {
new_page_table = NULL;
new_page_table_size = 0;
}
if (mem < heap_start){
Assert (more_pages != 0);
for (i = 0; i < more_pages; i++){
new_page_table [i] = Not_in_heap;
}
bcopy (page_table, new_page_table + more_pages, page_table_size);
(((heap_chunk_head *) mem) [-1]).next = heap_start;
heap_start = mem;
}else{
char **last;
char *cur;
if (mem >= heap_end) heap_end = mem + malloc_request;
if (more_pages != 0){
for (i = page_table_size; i < new_page_table_size; i++){
new_page_table [i] = Not_in_heap;
}
bcopy (page_table, new_page_table, page_table_size);
}
last = &heap_start;
cur = *last;
while (cur != NULL && cur < mem){
last = &((((heap_chunk_head *) cur) [-1]).next);
cur = *last;
}
(((heap_chunk_head *) mem) [-1]).next = cur;
*last = mem;
}
if (more_pages != 0){
free (page_table);
page_table = new_page_table;
page_table_size = new_page_table_size;
}
for (i = Page (mem); i < Page (mem + malloc_request); i++){
page_table [i] = In_heap;
}
stat_heap_size += malloc_request;
return Bp_hp (mem);
}
value alloc_shr (wosize, tag)
mlsize_t wosize;
tag_t tag;
{
char *hp, *new_block;
hp = fl_allocate (wosize);
if (hp == NULL){
new_block = expand_heap (wosize);
if (new_block == NULL) raise_out_of_memory ();
fl_add_block (new_block);
hp = fl_allocate (wosize);
}
Assert (Is_in_heap (Val_hp (hp)));
if (gc_phase == Phase_mark || (addr)hp >= (addr)gc_sweep_hp){
Hd_hp (hp) = Make_header (wosize, tag, Black);
}else{
Hd_hp (hp) = Make_header (wosize, tag, White);
}
allocated_words += Whsize_wosize (wosize);
if (allocated_words > Wsize_bsize (minor_heap_size)) force_minor_gc ();
return Val_hp (hp);
}
/* Use this function to tell the major GC to speed up when you use
finalized objects to automatically deallocate extra-heap objects.
The GC will do at least one cycle every [max] allocated words;
[mem] is the number of words allocated this time.
Note that only [mem/max] is relevant. You can use numbers of bytes
(or kilobytes, ...) instead of words. You can change units between
calls to [adjust_collector_speed].
*/
void adjust_gc_speed (mem, max)
mlsize_t mem, max;
{
if (max == 0) max = 1;
if (mem > max) mem = max;
extra_heap_memory += ((float) mem / max) * stat_heap_size;
if (extra_heap_memory > stat_heap_size){
extra_heap_memory = stat_heap_size;
}
if (extra_heap_memory > Wsize_bsize (minor_heap_size) / 2) force_minor_gc ();
}
/* You must use [initialize] to store the initial value in a field of
a shared block, unless you are sure the value is not a young block.
A block value [v] is a shared block if and only if [Is_in_heap (v)]
is true.
*/
/* [initialize] never calls the GC, so you may call it while an object is
unfinished (i.e. just after a call to [alloc_shr].) */
void initialize (fp, val)
value *fp;
value val;
{
*fp = val;
Assert (Is_in_heap (fp));
if (Is_block (val) && Is_young (val)){
*ref_table_ptr++ = fp;
if (ref_table_ptr >= ref_table_limit){
realloc_ref_table ();
}
}
}
/* You must use [modify] to change a field of an existing shared block,
unless you are sure the value being overwritten is not a shared block and
the value being written is not a young block. */
/* [modify] never calls the GC. */
void modify (fp, val)
value *fp;
value val;
{
Modify (fp, val);
}
char *stat_alloc (sz)
asize_t sz;
{
char *result = (char *) malloc (sz);
if (result == NULL) raise_out_of_memory ();
return result;
}
void stat_free (blk)
char * blk;
{
free (blk);
}
char *stat_resize (blk, sz)
char *blk;
asize_t sz;
{
char *result = (char *) realloc (blk, sz);
if (result == NULL) raise_out_of_memory ();
return result;
}
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