ikarus/runtime/ikarus-collect.c

1413 lines
39 KiB
C

#include "ikarus.h"
#include <stdlib.h>
#include <stdio.h>
#include <stdint.h>
#include <unistd.h>
#include <string.h>
#include <sys/mman.h>
#include <sys/types.h>
#include <assert.h>
#include <errno.h>
#define forward_ptr ((ikp)-1)
#define minimum_heap_size (pagesize * 1024 * 4)
#define maximum_heap_size (pagesize * 1024 * 8)
#define minimum_stack_size (pagesize * 128)
#define accounting 0
static int pair_count = 0;
static int symbol_count = 0;
static int closure_count = 0;
static int vector_count = 0;
static int record_count = 0;
static int continuation_count = 0;
static int string_count = 0;
static int htable_count = 0;
typedef struct qupages_t{
ikp p; /* pointer to the scan start */
ikp q; /* pointer to the scan end */
struct qupages_t* next;
} qupages_t;
typedef struct{
ikp ap;
ikp aq;
ikp ep;
ikp base;
} meta_t;
#define meta_ptrs 0
#define meta_code 1
#define meta_data 2
#define meta_weak 3
#define meta_pair 4
#define meta_count 5
static int extension_amount[meta_count] = {
4 * pagesize,
1 * pagesize,
4 * pagesize,
1 * pagesize,
1 * pagesize
};
static unsigned int meta_mt[meta_count] = {
pointers_mt,
code_mt,
data_mt,
weak_pairs_mt,
pointers_mt
};
#define generation_count 5 /* generations 0 (nursery), 1, 2, 3, 4 */
typedef struct{
meta_t meta[generation_count][meta_count];
qupages_t* queues [meta_count];
ikpcb* pcb;
unsigned int* segment_vector;
int collect_gen;
ikp tconc_ap;
ikp tconc_ep;
ikp tconc_base;
ikpages* tconc_queue;
} gc_t;
static unsigned int
next_gen_tag[generation_count] = {
(4 << meta_dirty_shift) | 1 | new_gen_tag,
(2 << meta_dirty_shift) | 2 | new_gen_tag,
(1 << meta_dirty_shift) | 3 | new_gen_tag,
(0 << meta_dirty_shift) | 4 | new_gen_tag,
(0 << meta_dirty_shift) | 4 | new_gen_tag
};
static ikp
meta_alloc_extending(int size, int old_gen, gc_t* gc, int meta_id){
int mapsize = align_to_next_page(size);
if(mapsize < extension_amount[meta_id]){
mapsize = extension_amount[meta_id];
}
meta_t* meta = &gc->meta[old_gen][meta_id];
if((meta_id != meta_data) && meta->base){
qupages_t* p = ik_malloc(sizeof(qupages_t));
ikp aq = meta->aq;
ikp ap = meta->ap;
ikp ep = meta->ep;
p->p = aq;
p->q = ap;
p->next = gc->queues[meta_id];
gc->queues[meta_id] = p;
ikp x = ap;
while(x < ep){
ref(x, 0) = 0;
x += wordsize;
}
}
ikp mem = ik_mmap_typed(
mapsize,
meta_mt[meta_id] | next_gen_tag[old_gen],
gc->pcb);
gc->segment_vector = gc->pcb->segment_vector;
meta->ap = mem + size;
meta->aq = mem;
meta->ep = mem + mapsize;
meta->base = mem;
return mem;
}
static inline ikp
meta_alloc(int size, int old_gen, gc_t* gc, int meta_id){
assert(size == align(size));
meta_t* meta = &gc->meta[old_gen][meta_id];
ikp ap = meta->ap;
ikp ep = meta->ep;
ikp nap = ap + size;
if(nap > ep){
return meta_alloc_extending(size, old_gen, gc, meta_id);
} else {
meta->ap = nap;
return ap;
}
}
static inline ikp
gc_alloc_new_ptr(int size, int old_gen, gc_t* gc){
assert(size == align(size));
return meta_alloc(size, old_gen, gc, meta_ptrs);
}
static inline ikp
gc_alloc_new_pair(int old_gen, gc_t* gc){
return meta_alloc(pair_size, old_gen, gc, meta_pair);
}
static inline ikp
gc_alloc_new_weak_pair(int old_gen, gc_t* gc){
meta_t* meta = &gc->meta[old_gen][meta_weak];
ikp ap = meta->ap;
ikp ep = meta->ep;
ikp nap = ap + pair_size;
if(nap > ep){
ikp mem = ik_mmap_typed(
pagesize,
meta_mt[meta_weak] | next_gen_tag[old_gen],
gc->pcb);
gc->segment_vector = gc->pcb->segment_vector;
meta->ap = mem + pair_size;
meta->aq = mem;
meta->ep = mem + pagesize;
meta->base = mem;
return mem;
} else {
meta->ap = nap;
return ap;
}
}
static inline ikp
gc_alloc_new_data(int size, int old_gen, gc_t* gc){
assert(size == align(size));
return meta_alloc(size, old_gen, gc, meta_data);
}
static inline ikp
gc_alloc_new_code(int size, int old_gen, gc_t* gc){
if(size < pagesize){
return meta_alloc(size, old_gen, gc, meta_code);
} else {
int memreq = align_to_next_page(size);
ikp mem = ik_mmap_code(memreq, next_gen_tag[old_gen], gc->pcb);
gc->segment_vector = gc->pcb->segment_vector;
qupages_t* p = ik_malloc(sizeof(qupages_t));
p->p = mem;
p->q = mem+size;
p->next = gc->queues[meta_code];
gc->queues[meta_code] = p;
return mem;
}
}
static void
gc_tconc_push_extending(gc_t* gc, ikp tcbucket){
if(gc->tconc_base){
ikpages* p = ik_malloc(sizeof(ikpages));
p->base = gc->tconc_base;
p->size = pagesize;
p->next = gc->tconc_queue;
gc->tconc_queue = p;
}
ikp ap = ik_mmap(pagesize);
ikp nap = ap + wordsize;
gc->tconc_base = ap;
gc->tconc_ap = nap;
gc->tconc_ep = ap + pagesize;
ref(ap,0) = tcbucket;
}
static inline void
gc_tconc_push(gc_t* gc, ikp tcbucket){
ikp ap = gc->tconc_ap;
ikp nap = ap + wordsize;
if(nap > gc->tconc_ep){
gc_tconc_push_extending(gc, tcbucket);
} else {
gc->tconc_ap = nap;
ref(ap,0) = tcbucket;
}
}
static ikp add_object(gc_t* gc, ikp x, char* caller);
static void collect_stack(gc_t*, ikp top, ikp base);
static void collect_loop(gc_t*);
static void fix_weak_pointers(gc_t*);
static void gc_add_tconcs(gc_t*);
/* ik_collect is called from scheme under the following conditions:
* 1. An attempt is made to allocate a small object and the ap is above
* the red line.
* 2. The current frame of the call is dead, so, upon return from ik_collect,
* the caller returns to its caller.
* 3. The frame-pointer of the caller to S_collect is saved at
* pcb->frame_pointer. No variables are live at that frame except for
* the return point (at *(pcb->frame_pointer)).
* 4. S_collect must return a new ap (in pcb->allocation_pointer) that has
* at least 2 pages of memory free.
* 5. S_collect must also update pcb->allocaton_redline to be 2 pages below
* the real end of heap.
* 6. ik_collect should not move the stack.
*/
ikpcb* ik_collect(int req, ikpcb* pcb);
ikpcb* ik_collect_vararg(int req, ikpcb* pcb){
return ik_collect(req, pcb);
}
static int collection_id_to_gen(int id){
if((id & 255) == 255) { return 4; }
if((id & 63) == 63) { return 3; }
if((id & 15) == 15) { return 2; }
if((id & 3) == 3) { return 1; }
return 0;
}
static void scan_dirty_pages(gc_t*);
static void deallocate_unused_pages(gc_t*);
static void fix_new_pages(gc_t* gc);
ikpcb*
ik_collect(int req, ikpcb* pcb){
struct rusage t0, t1;
getrusage(RUSAGE_SELF, &t0);
gc_t gc;
bzero(&gc, sizeof(gc_t));
gc.pcb = pcb;
gc.segment_vector = pcb->segment_vector;
gc.collect_gen = collection_id_to_gen(pcb->collection_id);
pcb->collection_id++;
#ifndef NDEBUG
fprintf(stderr, "ik_collect entry %d free=%d (collect gen=%d/id=%d)\n",
req,
(unsigned int) pcb->allocation_redline
- (unsigned int) pcb->allocation_pointer,
gc.collect_gen, pcb->collection_id-1);
#endif
/* the roots are:
* 0. dirty pages not collected in this run
* 1. the stack
* 2. the next continuation
* 3. the oblist
*/
scan_dirty_pages(&gc);
collect_stack(&gc, pcb->frame_pointer, pcb->frame_base - wordsize);
pcb->next_k = add_object(&gc, pcb->next_k, "main");
pcb->oblist = add_object(&gc, pcb->oblist, "main");
/* now we trace all live objects */
collect_loop(&gc);
fix_weak_pointers(&gc);
/* now deallocate all unused pages */
deallocate_unused_pages(&gc);
fix_new_pages(&gc);
pcb->allocation_pointer = pcb->heap_base;
gc_add_tconcs(&gc);
pcb->weak_pairs_ap = 0;
pcb->weak_pairs_ep = 0;
if(accounting){
fprintf(stderr,
"[%d cons|%d sym|%d cls|%d vec|%d rec|%d cck|%d str|%d htb]\n",
pair_count,
symbol_count,
closure_count,
vector_count,
record_count,
continuation_count,
string_count,
htable_count);
pair_count = 0;
symbol_count = 0;
closure_count = 0;
vector_count = 0;
record_count = 0;
continuation_count = 0;
string_count = 0;
htable_count = 0;
}
//ik_dump_metatable(pcb);
#ifndef NDEBUG
fprintf(stderr, "collect done\n");
#endif
getrusage(RUSAGE_SELF, &t1);
pcb->collect_utime.tv_usec += t1.ru_utime.tv_usec - t0.ru_utime.tv_usec;
pcb->collect_utime.tv_sec += t1.ru_utime.tv_sec - t0.ru_utime.tv_sec;
if (pcb->collect_utime.tv_usec >= 1000000){
pcb->collect_utime.tv_usec -= 1000000;
pcb->collect_utime.tv_sec += 1;
}
else if (pcb->collect_utime.tv_usec < 0){
pcb->collect_utime.tv_usec += 1000000;
pcb->collect_utime.tv_sec -= 1;
}
pcb->collect_stime.tv_usec += t1.ru_stime.tv_usec - t0.ru_stime.tv_usec;
pcb->collect_stime.tv_sec += t1.ru_stime.tv_sec - t0.ru_stime.tv_sec;
if (pcb->collect_stime.tv_usec >= 1000000){
pcb->collect_stime.tv_usec -= 1000000;
pcb->collect_stime.tv_sec += 1;
}
else if (pcb->collect_stime.tv_usec < 0){
pcb->collect_stime.tv_usec += 1000000;
pcb->collect_stime.tv_sec -= 1;
}
return pcb;
}
#define disp_frame_offset -13
#define disp_multivalue_rp -9
#define CODE_EXTENSION_SIZE (pagesize)
//X static ikp
//X gc_alloc_new_code_extending(int size, int old_gen, gc_t* gc){
//X int mapsize = align_to_next_page(size);
//X if(mapsize < CODE_EXTENSION_SIZE){
//X mapsize = CODE_EXTENSION_SIZE;
//X }
//X if(gc->gen[old_gen].code_base){
//X qupages_t* p = ik_malloc(sizeof(qupages_t));
//X ikp aq = gc->gen[old_gen].code_aq;
//X ikp ap = gc->gen[old_gen].code_ap;
//X ikp ep = gc->gen[old_gen].code_ep;
//X p->p = aq;
//X p->q = ap;
//X p->next = gc->code_queue;
//X gc->code_queue = p;
//X ikp x = ap;
//X while(x < ep){
//X ref(x, 0) = 0;
//X x += wordsize;
//X }
//X }
//X ikp mem = ik_mmap_typed(
//X mapsize,
//X code_mt | next_gen_tag[old_gen],
//X gc->pcb);
//X gc->segment_vector = gc->pcb->segment_vector;
//X gc->gen[old_gen].code_ap = mem + size;
//X gc->gen[old_gen].code_aq = mem;
//X gc->gen[old_gen].code_ep = mem + mapsize;
//X gc->gen[old_gen].code_base = mem;
//X return mem;
//X }
//X
static int alloc_code_count = 0;
static ikp
add_code_entry(gc_t* gc, ikp entry){
ikp x = entry - disp_code_data;
if(ref(x,0) == forward_ptr){
return ref(x,wordsize) + off_code_data;
}
int idx = page_index(x);
unsigned int t = gc->segment_vector[idx];
int gen = t & gen_mask;
if(gen > gc->collect_gen){
return entry;
}
int code_size = unfix(ref(x, disp_code_code_size));
ikp reloc_vec = ref(x, disp_code_reloc_vector);
ikp freevars = ref(x, disp_code_freevars);
int required_mem = align(disp_code_data + code_size);
if(required_mem >= pagesize){
int new_tag = next_gen_tag[gen];
int idx = page_index(x);
gc->segment_vector[idx] = new_tag | code_mt;
int i;
for(i=pagesize, idx++; i<required_mem; i+=pagesize, idx++){
gc->segment_vector[idx] = new_tag | data_mt;
}
qupages_t* p = ik_malloc(sizeof(qupages_t));
p->p = x;
p->q = x+required_mem;
p->next = gc->queues[meta_code];
gc->queues[meta_code] = p;
return entry;
} else {
ikp y = gc_alloc_new_code(required_mem, gen, gc);
ref(y, 0) = code_tag;
ref(y, disp_code_code_size) = fix(code_size);
ref(y, disp_code_reloc_vector) = reloc_vec;
ref(y, disp_code_freevars) = freevars;
memcpy(y+disp_code_data, x+disp_code_data, code_size);
ref(x, 0) = forward_ptr;
ref(x, wordsize) = y + vector_tag;
return y+disp_code_data;
}
}
#define DEBUG_STACK 0
static void collect_stack(gc_t* gc, ikp top, ikp end){
if(DEBUG_STACK){
fprintf(stderr, "collecting stack from 0x%08x .. 0x%08x\n",
(int) top, (int) end);
}
while(top < end){
if(DEBUG_STACK){
fprintf(stderr, "collecting frame at 0x%08x: ", (int) top);
}
ikp rp = ref(top, 0);
int rp_offset = unfix(ref(rp, disp_frame_offset));
if(DEBUG_STACK){
fprintf(stderr, "rp_offset=%d\n", rp_offset);
}
if(rp_offset <= 0){
fprintf(stderr, "invalid rp_offset %d\n", rp_offset);
exit(-1);
}
/* since the return point is alive, we need to find the code
* object containing it and mark it live as well. the rp is
* updated to reflect the new code object. */
int code_offset = rp_offset - disp_frame_offset;
ikp code_entry = rp - code_offset;
ikp new_code_entry = add_code_entry(gc, code_entry);
ikp new_rp = new_code_entry + code_offset;
ref(top, 0) = new_rp;
/* now for some livemask action.
* every return point has a live mark above it. the live mask
* is a sequence of bytes (every byte for 8 frame cells). the
* size of the live mask is determined by the size of the frame.
* this is how the call frame instruction sequence looks like:
*
* | ... |
* | code junk |
* +------------+
* | byte 0 | for fv0 .. fv7
* | byte 1 | for fv8 .. fv15
* | ... | ...
* +------------+
* | framesize |
* | word |
* +------------+
* | multivalue |
* | word |
* +------------+
* | frameoffst | the frame offset determined how far its
* | word | address is off from the start of the code
* +------------+
* | padding | the size of this part is fixed so that we
* | and call | can correlate the frame info (above) with rp
* +------------+
* | code junk | <---- rp
* | ... |
*
* WITH ONE EXCEPTION:
* if the framesize is 0, then the actual frame size is stored
* on the stack immediately below the return point.
* there is no live mask in this case, instead all values in the
* frame are live.
*/
int framesize = (int) ref(rp, disp_frame_size);
if(DEBUG_STACK){
fprintf(stderr, "fs=%d\n", framesize);
}
if(framesize < 0){
fprintf(stderr, "invalid frame size %d\n", framesize);
exit(-1);
}
else if(framesize == 0){
framesize = (int)ref(top, wordsize);
if(framesize <= 0){
fprintf(stderr, "invalid redirected framesize=%d\n", framesize);
exit(-1);
}
ikp base = top + framesize - wordsize;
while(base > top){
ikp new_obj = add_object(gc,ref(base,0), "frame");
ref(base,0) = new_obj;
base -= wordsize;
}
} else {
int frame_cells = framesize >> fx_shift;
int bytes_in_mask = (frame_cells+7) >> 3;
unsigned char* mask = rp + disp_frame_size - bytes_in_mask;
ikp* fp = (ikp*)(top + framesize);
int i;
for(i=0; i<bytes_in_mask; i++, fp-=8){
unsigned char m = mask[i];
#if DEBUG_STACK
fprintf(stderr, "m[%d]=0x%x\n", i, m);
#endif
if(m & 0x01) { fp[-0] = add_object(gc, fp[-0], "frame0"); }
if(m & 0x02) { fp[-1] = add_object(gc, fp[-1], "frame1"); }
if(m & 0x04) { fp[-2] = add_object(gc, fp[-2], "frame2"); }
if(m & 0x08) { fp[-3] = add_object(gc, fp[-3], "frame3"); }
if(m & 0x10) { fp[-4] = add_object(gc, fp[-4], "frame4"); }
if(m & 0x20) { fp[-5] = add_object(gc, fp[-5], "frame5"); }
if(m & 0x40) { fp[-6] = add_object(gc, fp[-6], "frame6"); }
if(m & 0x80) { fp[-7] = add_object(gc, fp[-7], "frame7"); }
}
}
top += framesize;
}
if(top != end){
fprintf(stderr, "frames did not match up 0x%08x .. 0x%08x\n",
(int) top, (int) end);
exit(-1);
}
if(DEBUG_STACK){
fprintf(stderr, "done with stack!\n");
}
}
static void
add_list(gc_t* gc, unsigned int t, int gen, ikp x, ikp* loc){
int collect_gen = gc->collect_gen;
while(1){
ikp fst = ref(x, off_car);
ikp snd = ref(x, off_cdr);
ikp y;
if((t & type_mask) != weak_pairs_type){
y = gc_alloc_new_pair(gen, gc) + pair_tag;
} else {
y = gc_alloc_new_weak_pair(gen, gc) + pair_tag;
}
*loc = y;
ref(x,off_car) = forward_ptr;
ref(x,off_cdr) = y;
ref(y,off_car) = fst;
int stag = tagof(snd);
if(stag == pair_tag){
if(ref(snd, -pair_tag) == forward_ptr){
ref(y, off_cdr) = ref(snd, wordsize-pair_tag);
return;
}
else {
t = gc->segment_vector[page_index(snd)];
gen = t & gen_mask;
if(gen > collect_gen){
ref(y, off_cdr) = snd;
return;
} else {
x = snd;
loc = (ikp*)(y + off_cdr);
/* don't return */
}
}
}
else if( (stag == immediate_tag)
|| (stag == 0)
|| (stag == (1<<fx_shift))) {
ref(y,off_cdr) = snd;
return;
}
else if (ref(snd, -stag) == forward_ptr){
ref(y, off_cdr) = ref(snd, wordsize-stag);
return;
}
else {
ref(y, off_cdr) = add_object(gc, snd, "add_list");
return;
}
}
}
static ikp
add_object(gc_t* gc, ikp x, char* caller){
if(is_fixnum(x)){
return x;
}
if(x == forward_ptr){
fprintf(stderr, "GOTCHA\n");
exit(-1);
}
int tag = tagof(x);
if(tag == immediate_tag){
return x;
}
ikp fst = ref(x, -tag);
if(fst == forward_ptr){
/* already moved */
return ref(x, wordsize-tag);
}
unsigned int t = gc->segment_vector[page_index(x)];
int gen = t & gen_mask;
if(gen > gc->collect_gen){
return x;
}
if(tag == pair_tag){
ikp y;
add_list(gc, t, gen, x, &y);
return y;
}
else if(tag == symbol_tag){
ikp y = gc_alloc_new_ptr(symbol_size, gen, gc) + symbol_tag;
ref(y, off_symbol_string) = ref(x, off_symbol_string);
ref(y, off_symbol_ustring) = ref(x, off_symbol_ustring);
ref(y, off_symbol_value) = ref(x, off_symbol_value);
ref(y, off_symbol_plist) = ref(x, off_symbol_plist);
ref(y, off_symbol_system_value) = ref(x, off_symbol_system_value);
ref(y, off_symbol_system_plist) = ref(x, off_symbol_system_plist);
ref(x, -symbol_tag) = forward_ptr;
ref(x, wordsize-symbol_tag) = y;
if(accounting){
symbol_count++;
}
return y;
}
else if(tag == closure_tag){
int size = disp_closure_data+
(int) ref(fst, disp_code_freevars - disp_code_data);
if(size > 1024){
fprintf(stderr, "large closure size=0x%08x\n", size);
}
int asize = align(size);
ikp y = gc_alloc_new_ptr(asize, gen, gc) + closure_tag;
ref(y, asize-closure_tag-wordsize) = 0;
memcpy(y-closure_tag, x-closure_tag, size);
ref(y,-closure_tag) = add_code_entry(gc, ref(y,-closure_tag));
ref(x,-closure_tag) = forward_ptr;
ref(x,wordsize-closure_tag) = y;
if(accounting){
closure_count++;
}
return y;
}
else if(tag == vector_tag){
if(is_fixnum(fst)){
/* real vector */
int size = (int)fst;
assert(size >= 0);
int memreq = align(size + disp_vector_data);
ikp y = gc_alloc_new_ptr(memreq, gen, gc) + vector_tag;
ref(y, disp_vector_length-vector_tag) = fst;
ref(y, memreq-vector_tag-wordsize) = 0;
memcpy(y+off_vector_data, x+off_vector_data, size);
ref(x,-vector_tag) = forward_ptr;
ref(x,wordsize-vector_tag) = y;
if(accounting){
vector_count++;
}
return y;
}
else if(tagof(fst) == rtd_tag){
/* record */
int size = (int) ref(fst, off_rtd_length);
if(size > 4096){
fprintf(stderr, "large rec size=0x%08x\n", size);
}
int memreq = align(size + disp_record_data);
ikp y = gc_alloc_new_ptr(memreq, gen, gc) + vector_tag;
ref(y, memreq-vector_tag-wordsize) = 0;
memcpy(y-vector_tag, x-vector_tag, size+wordsize);
ref(x,-vector_tag) = forward_ptr;
ref(x,wordsize-vector_tag) = y;
if(accounting){
record_count++;
}
return y;
}
else if(fst == code_tag){
ikp entry = x + off_code_data;
ikp new_entry = add_code_entry(gc, entry);
return new_entry - off_code_data;
}
else if(fst == continuation_tag){
ikp top = ref(x, off_continuation_top);
int size = (int) ref(x, off_continuation_size);
if(size > 4096){
fprintf(stderr, "large cont size=0x%08x\n", size);
}
ikp next = ref(x, off_continuation_next);
ikp y = gc_alloc_new_ptr(continuation_size, gen, gc) + vector_tag;
ref(x, -vector_tag) = forward_ptr;
ref(x, wordsize-vector_tag) = y;
ikp new_top = gc_alloc_new_data(align(size), gen, gc);
memcpy(new_top, top, size);
collect_stack(gc, new_top, new_top + size);
ref(y, -vector_tag) = continuation_tag;
ref(y, off_continuation_top) = new_top;
ref(y, off_continuation_size) = (ikp) size;
ref(y, off_continuation_next) = next;
if(accounting){
continuation_count++;
}
return y;
}
else if(tagof(fst) == pair_tag){
/* tcbucket */
ikp y = gc_alloc_new_ptr(tcbucket_size, gen, gc) + vector_tag;
ref(y,off_tcbucket_tconc) = fst;
ikp key = ref(x, off_tcbucket_key);
ref(y,off_tcbucket_key) = key;
ref(y,off_tcbucket_val) = ref(x, off_tcbucket_val);
ref(y,off_tcbucket_next) = ref(x, off_tcbucket_next);
ref(y,off_tcbucket_dlink_next) = ref(x, off_tcbucket_dlink_next);
ref(y,off_tcbucket_dlink_prev) = ref(x, off_tcbucket_dlink_prev);
if((! is_fixnum(key)) && (tagof(key) != immediate_tag)){
unsigned int kt = gc->segment_vector[page_index(key)];
if((kt & gen_mask) <= gc->collect_gen){
/* key is moved */
gc_tconc_push(gc, y);
}
}
ref(x, -vector_tag) = forward_ptr;
ref(x, wordsize-vector_tag) = y;
return y;
}
else if((((int)fst) & port_mask) == port_tag){
ikp y = gc_alloc_new_ptr(port_size, gen, gc) + vector_tag;
ref(y, -vector_tag) = fst;
int i;
for(i=wordsize; i<port_size; i+=wordsize){
ref(y, i-vector_tag) = ref(x, i-vector_tag);
}
ref(x, -vector_tag) = forward_ptr;
ref(x, wordsize-vector_tag) = y;
return y;
}
else if((((int)fst) & bignum_mask) == bignum_tag){
int len = ((unsigned int)fst) >> bignum_length_shift;
int memreq = align(disp_bignum_data + len*wordsize);
ikp new = gc_alloc_new_data(memreq, gen, gc) + vector_tag;
memcpy(new-vector_tag, x, memreq);
ref(x, 0) = forward_ptr;
ref(x, wordsize) = new;
return new;
}
else {
fprintf(stderr, "unhandled vector with fst=0x%08x\n", (int)fst);
exit(-1);
}
}
else if(tag == string_tag){
if(is_fixnum(fst)){
int strlen = unfix(fst);
int memreq = align(strlen + disp_string_data + 1);
ikp new_str = gc_alloc_new_data(memreq, gen, gc) + string_tag;
ref(new_str, off_string_length) = fst;
memcpy(new_str+off_string_data,
x + off_string_data,
strlen + 1);
ref(x, -string_tag) = forward_ptr;
ref(x, wordsize-string_tag) = new_str;
if(accounting){
string_count++;
}
return new_str;
}
else {
fprintf(stderr, "unhandled string 0x%08x with fst=0x%08x\n",
(int)x, (int)fst);
exit(-1);
}
}
fprintf(stderr, "unhandled tag: %d\n", tag);
exit(-1);
}
static void
relocate_new_code(ikp x, gc_t* gc){
ikp relocvector = ref(x, disp_code_reloc_vector);
relocvector = add_object(gc, relocvector, "reloc");
ref(x, disp_code_reloc_vector) = relocvector;
int relocsize = (int)ref(relocvector, off_vector_length);
ikp p = relocvector + off_vector_data;
ikp q = p + relocsize;
ikp code = x + disp_code_data;
while(p < q){
int r = unfix(ref(p, 0));
int tag = r & 3;
int code_off = r >> 2;
if(tag == 0){
/* undisplaced pointer */
ikp old_object = ref(p, wordsize);
ikp new_object = add_object(gc, old_object, "reloc");
ref(code, code_off) = new_object;
p += (2*wordsize);
}
else if(tag == 2){
/* displaced pointer */
int obj_off = unfix(ref(p, wordsize));
ikp old_object = ref(p, 2*wordsize);
ikp new_object = add_object(gc, old_object, "reloc");
ref(code, code_off) = new_object + obj_off;
p += (3 * wordsize);
}
else if(tag == 3){
/* displaced relative pointer */
int obj_off = unfix(ref(p, wordsize));
ikp obj = add_object(gc, ref(p, 2*wordsize), "reloc");
ikp displaced_object = obj + obj_off;
ikp next_word = code + code_off + wordsize;
ikp relative_distance = displaced_object - (int)next_word;
ref(next_word, -wordsize) = relative_distance;
p += (3*wordsize);
}
else if(tag == 1){
/* do nothing */
p += (2 * wordsize);
}
else {
fprintf(stderr, "invalid rtag %d in 0x%08x\n", tag, r);
exit(-1);
}
}
}
static void
collect_loop(gc_t* gc){
int done;
do{
done = 1;
{ /* scan the pending pairs pages */
qupages_t* qu = gc->queues[meta_pair];
if(qu){
done = 0;
gc->queues[meta_pair] = 0;
do{
ikp p = qu->p;
ikp q = qu->q;
while(p < q){
ref(p,0) = add_object(gc, ref(p,0), "loop");
p += (2*wordsize);
}
qupages_t* next = qu->next;
ik_free(qu, sizeof(qupages_t));
qu = next;
} while(qu);
}
}
{ /* scan the pending pointer pages */
qupages_t* qu = gc->queues[meta_ptrs];
if(qu){
done = 0;
gc->queues[meta_ptrs] = 0;
do{
ikp p = qu->p;
ikp q = qu->q;
while(p < q){
ref(p,0) = add_object(gc, ref(p,0), "pending");
p += wordsize;
}
qupages_t* next = qu->next;
ik_free(qu, sizeof(qupages_t));
qu = next;
} while(qu);
}
}
{ /* scan the pending code objects */
qupages_t* codes = gc->queues[meta_code];
if(codes){
gc->queues[meta_code] = 0;
done = 0;
do{
ikp p = codes->p;
ikp q = codes->q;
while(p < q){
relocate_new_code(p, gc);
alloc_code_count--;
p += align(disp_code_data + unfix(ref(p, disp_code_code_size)));
}
qupages_t* next = codes->next;
ik_free(codes, sizeof(qupages_t));
codes = next;
} while(codes);
}
}
{/* see if there are any remaining in the main ptr segment */
int i;
for(i=0; i<=gc->collect_gen; i++){
meta_t* meta = &gc->meta[i][meta_pair];
ikp p = meta->aq;
ikp q = meta->ap;
if(p < q){
done = 0;
do{
meta->aq = q;
while(p < q){
ref(p,0) = add_object(gc, ref(p,0), "rem");
p += (2*wordsize);
}
p = meta->aq;
q = meta->ap;
} while (p < q);
}
}
for(i=0; i<=gc->collect_gen; i++){
meta_t* meta = &gc->meta[i][meta_ptrs];
ikp p = meta->aq;
ikp q = meta->ap;
if(p < q){
done = 0;
do{
meta->aq = q;
while(p < q){
ref(p,0) = add_object(gc, ref(p,0), "rem2");
p += wordsize;
}
p = meta->aq;
q = meta->ap;
} while (p < q);
}
}
for(i=0; i<=gc->collect_gen; i++){
meta_t* meta = &gc->meta[i][meta_code];
ikp p = meta->aq;
ikp q = meta->ap;
if(p < q){
done = 0;
do{
meta->aq = q;
do{
alloc_code_count--;
relocate_new_code(p, gc);
p += align(disp_code_data + unfix(ref(p, disp_code_code_size)));
} while (p < q);
p = meta->aq;
q = meta->ap;
} while (p < q);
}
}
}
/* phew */
} while (! done);
{
int i;
for(i=0; i<=gc->collect_gen; i++){
meta_t* meta = &gc->meta[i][meta_pair];
ikp p = meta->ap;
ikp q = meta->ep;
while(p < q){
ref(p, 0) = 0;
p += wordsize;
}
}
for(i=0; i<=gc->collect_gen; i++){
meta_t* meta = &gc->meta[i][meta_ptrs];
ikp p = meta->ap;
ikp q = meta->ep;
while(p < q){
ref(p, 0) = 0;
p += wordsize;
}
}
for(i=0; i<=gc->collect_gen; i++){
meta_t* meta = &gc->meta[i][meta_weak];
ikp p = meta->ap;
ikp q = meta->ep;
while(p < q){
ref(p, 0) = 0;
p += wordsize;
}
}
for(i=0; i<=gc->collect_gen; i++){
meta_t* meta = &gc->meta[i][meta_code];
ikp p = meta->ap;
ikp q = meta->ep;
while(p < q){
ref(p, 0) = 0;
p += wordsize;
}
}
}
}
static void
fix_weak_pointers(gc_t* gc){
unsigned int* segment_vec = gc->segment_vector;
ikpcb* pcb = gc->pcb;
int lo_idx = page_index(pcb->memory_base);
int hi_idx = page_index(pcb->memory_end);
int i = lo_idx;
int collect_gen = gc->collect_gen;
while(i < hi_idx){
unsigned int t = segment_vec[i];
if((t & type_mask) == weak_pairs_type){
int gen = t & gen_mask;
if(gen > collect_gen){
ikp p = (ikp)(i << pageshift);
ikp q = p + pagesize;
while(p < q){
ikp x = ref(p, 0);
if(! is_fixnum(x)){
int tag = tagof(x);
if(tag != immediate_tag){
ikp fst = ref(x, -tag);
if(fst == forward_ptr){
ref(p, 0) = ref(x, wordsize-tag); }
else {
int x_gen = segment_vec[page_index(x)] & gen_mask;
if(x_gen <= collect_gen){
ref(p, 0) = bwp_object; } } } }
p += (2*wordsize); } } }
i++; } }
static unsigned int dirty_mask[generation_count] = {
0x88888888,
0xCCCCCCCC,
0xEEEEEEEE,
0xFFFFFFFF,
0x00000000
};
static unsigned int cleanup_mask[generation_count] = {
0x00000000,
0x88888888,
0xCCCCCCCC,
0xEEEEEEEE,
0xFFFFFFFF
};
static void
scan_dirty_pointers_page(gc_t* gc, int page_idx, int mask){
unsigned int* segment_vec = gc->segment_vector;
unsigned int* dirty_vec = gc->pcb->dirty_vector;
unsigned int t = segment_vec[page_idx];
unsigned int d = dirty_vec[page_idx];
unsigned int masked_d = d & mask;
ikp p = (ikp)(page_idx << pageshift);
int j;
unsigned int new_d = 0;
for(j=0; j<cards_per_page; j++){
if(masked_d & (0xF << (j*meta_dirty_shift))){
/* dirty card */
ikp q = p + cardsize;
unsigned int card_d = 0;
while(p < q){
ikp x = ref(p, 0);
if(is_fixnum(x) || (tagof(x) == immediate_tag)){
/* do nothing */
} else {
ikp y = add_object(gc, x, "nothing");
segment_vec = gc->segment_vector;
ref(p, 0) = y;
card_d = card_d | segment_vec[page_index(y)];
}
p += wordsize;
}
card_d = (card_d & meta_dirty_mask) >> meta_dirty_shift;
new_d = new_d | (card_d<<(j*meta_dirty_shift));
} else {
p += cardsize;
new_d = new_d | (d & (0xF << (j*meta_dirty_shift)));
}
}
dirty_vec = gc->pcb->dirty_vector;
new_d = new_d & cleanup_mask[t & gen_mask];
dirty_vec[page_idx] = new_d;
}
static void
scan_dirty_code_page(gc_t* gc, int page_idx, unsigned int mask){
ikp p = (ikp)(page_idx << pageshift);
ikp start = p;
ikp q = p + pagesize;
unsigned int* segment_vec = gc->segment_vector;
unsigned int* dirty_vec = gc->pcb->dirty_vector;
//unsigned int d = dirty_vec[page_idx];
unsigned int t = segment_vec[page_idx];
//unsigned int masked_d = d & mask;
unsigned int new_d = 0;
while(p < q){
if(ref(p, 0) != code_tag){
p = q;
}
else {
int j = ((int)p - (int)start) / cardsize;
int code_size = unfix(ref(p, disp_code_code_size));
relocate_new_code(p, gc);
segment_vec = gc->segment_vector;
ikp rvec = ref(p, disp_code_reloc_vector);
int len = (int)ref(rvec, off_vector_length);
assert(len >= 0);
int i;
unsigned int code_d = segment_vec[page_index(rvec)];
for(i=0; i<len; i+=wordsize){
ikp r = ref(rvec, i+off_vector_data);
if(is_fixnum(r) || (tagof(r) == immediate_tag)){
/* do nothing */
} else {
r = add_object(gc, r, "nothing2");
segment_vec = gc->segment_vector;
code_d = code_d | segment_vec[page_index(r)];
}
}
new_d = new_d | (code_d<<(j*meta_dirty_shift));
p += align(code_size + disp_code_data);
}
}
dirty_vec = gc->pcb->dirty_vector;
new_d = new_d & cleanup_mask[t & gen_mask];
dirty_vec[page_idx] = new_d;
}
/* scanning dirty weak pointers should add the cdrs of the pairs
* but leave the cars unmodified. The dirty mask is also kept
* unmodified so that the after-pass fixes it.
*/
static void
scan_dirty_weak_pointers_page(gc_t* gc, int page_idx, int mask){
unsigned int* dirty_vec = gc->pcb->dirty_vector;
unsigned int d = dirty_vec[page_idx];
unsigned int masked_d = d & mask;
ikp p = (ikp)(page_idx << pageshift);
int j;
for(j=0; j<cards_per_page; j++){
if(masked_d & (0xF << (j*meta_dirty_shift))){
/* dirty card */
ikp q = p + cardsize;
while(p < q){
ikp x = ref(p, wordsize);
if(is_fixnum(x) || tagof(x) == immediate_tag){
/* do nothing */
} else {
ikp y = add_object(gc, x, "nothing3");
ref(p, wordsize) = y;
}
p += (2*wordsize);
}
} else {
p += cardsize;
}
}
}
static void
scan_dirty_pages(gc_t* gc){
ikpcb* pcb = gc->pcb;
int lo_idx = page_index(pcb->memory_base);
int hi_idx = page_index(pcb->memory_end);
unsigned int* dirty_vec = pcb->dirty_vector;
unsigned int* segment_vec = pcb->segment_vector;
int collect_gen = gc->collect_gen;
unsigned int mask = dirty_mask[collect_gen];
int i = lo_idx;
while(i < hi_idx){
unsigned int d = dirty_vec[i];
if(d & mask){
unsigned int t = segment_vec[i];
if((t & gen_mask) > collect_gen){
int type = t & type_mask;
if(type == pointers_type){
scan_dirty_pointers_page(gc, i, mask);
dirty_vec = pcb->dirty_vector;
segment_vec = pcb->segment_vector;
}
else if (type == weak_pairs_type){
if((t & gen_mask) > collect_gen){
scan_dirty_weak_pointers_page(gc, i, mask);
dirty_vec = pcb->dirty_vector;
segment_vec = pcb->segment_vector;
}
}
else if (type == code_type){
if((t & gen_mask) > collect_gen){
scan_dirty_code_page(gc, i, mask);
dirty_vec = pcb->dirty_vector;
segment_vec = pcb->segment_vector;
}
}
else if (t & scannable_mask) {
fprintf(stderr, "BUG: unhandled scan of type 0x%08x\n", t);
exit(-1);
}
}
}
i++;
}
}
static void
deallocate_unused_pages(gc_t* gc){
ikpcb* pcb = gc->pcb;
int collect_gen = gc->collect_gen;
unsigned int* segment_vec = pcb->segment_vector;
unsigned char* memory_base = pcb->memory_base;
unsigned char* memory_end = pcb->memory_end;
int lo_idx = page_index(memory_base);
int hi_idx = page_index(memory_end);
int i = lo_idx;
while(i < hi_idx){
unsigned int t = segment_vec[i];
if(t & dealloc_mask){
int gen = t & old_gen_mask;
if(gen <= collect_gen){
/* we're interested */
if(t & new_gen_mask){
/* do nothing yet */
} else {
ik_munmap_from_segment((unsigned char*)(i<<pageshift),pagesize,pcb);
}
}
}
i++;
}
}
static void
fix_new_pages(gc_t* gc){
ikpcb* pcb = gc->pcb;
unsigned int* segment_vec = pcb->segment_vector;
unsigned int* dirty_vec = pcb->dirty_vector;
unsigned char* memory_base = pcb->memory_base;
unsigned char* memory_end = pcb->memory_end;
int lo_idx = page_index(memory_base);
int hi_idx = page_index(memory_end);
int i = lo_idx;
while(i < hi_idx){
unsigned int t = segment_vec[i];
if((t & new_gen_mask) ||
((t & type_mask) == weak_pairs_type)){
segment_vec[i] = t & ~new_gen_mask;
int page_gen = t & old_gen_mask;
if(((t & type_mask) == pointers_type) ||
((t & type_mask) == weak_pairs_type)){
ikp p = (ikp)(i << pageshift);
unsigned int d = 0;
int j;
for(j=0; j<cards_per_page; j++){
ikp q = p + cardsize;
unsigned int card_d = 0;
while(p < q){
ikp x = ref(p, 0);
if(is_fixnum(x) || (tagof(x) == immediate_tag)){
/* nothing */
} else {
card_d = card_d | segment_vec[page_index(x)];
}
p += wordsize;
}
card_d = (card_d & meta_dirty_mask) >> meta_dirty_shift;
d = d | (card_d<<(j*meta_dirty_shift));
}
dirty_vec[i] = d & cleanup_mask[page_gen];
}
else if((t & type_mask) == code_type){
/* FIXME: scan codes */
ikp page_base = (ikp)(i << pageshift);
ikp p = page_base;
ikp q = p + pagesize;
int err = mprotect(page_base, pagesize, PROT_READ|PROT_WRITE|PROT_EXEC);
if(err){
fprintf(stderr, "cannot protect code page: %s\n", strerror(errno));
exit(-1);
}
unsigned int d = 0;
while(p < q){
if(ref(p, 0) != code_tag){
p = q;
}
else {
ikp rvec = ref(p, disp_code_reloc_vector);
int size = (int)ref(rvec, off_vector_length);
ikp vp = rvec + off_vector_data;
ikp vq = vp + size;
unsigned int code_d = segment_vec[page_index(rvec)];
while(vp < vq){
ikp x = ref(vp, 0);
if(is_fixnum(x) || (tagof(x) == immediate_tag)){
/* do nothing */
} else {
code_d = code_d || segment_vec[page_index(x)];
}
vp += wordsize;
}
code_d = (code_d & meta_dirty_mask) >> meta_dirty_shift;
int j = ((int)p - (int)page_base)/cardsize;
d = d | (code_d<<(j*meta_dirty_shift));
p += align(disp_code_data + unfix(ref(p, disp_code_code_size)));
}
}
dirty_vec[i] = d & cleanup_mask[page_gen];
}
else {
if(t & scannable_mask){
fprintf(stderr, "unscanned 0x%08x\n", t);
exit(-1);
}
}
}
i++;
}
}
static void
add_one_tconc(ikpcb* pcb, ikp tcbucket){
ikp tc = ref(tcbucket, off_tcbucket_tconc);
assert(tagof(tc) == pair_tag);
ikp d = ref(tc, off_cdr);
assert(tagof(d) == pair_tag);
ikp new_pair = ik_alloc(pcb, pair_size) + pair_tag;
ref(d, off_car) = tcbucket;
ref(d, off_cdr) = new_pair;
ref(new_pair, off_car) = false_object;
ref(new_pair, off_cdr) = false_object;
ref(tc, off_cdr) = new_pair;
ref(tcbucket, -vector_tag) = (ikp)(tcbucket_size - wordsize);
pcb->dirty_vector[page_index(tc)] = -1;
pcb->dirty_vector[page_index(d)] = -1;
}
static void
gc_add_tconcs(gc_t* gc){
if(gc->tconc_base == 0){
return;
}
ikpcb* pcb = gc->pcb;
{
ikp p = gc->tconc_base;
ikp q = gc->tconc_ap;
while(p < q){
add_one_tconc(pcb, ref(p,0));
p += wordsize;
}
}
ikpages* qu = gc->tconc_queue;
while(qu){
ikp p = qu->base;
ikp q = p + qu->size;
while(p < q){
add_one_tconc(pcb, ref(p,0));
p += wordsize;
}
ikpages* next = qu->next;
ik_free(qu, sizeof(ikpages));
qu = next;
}
}