StgLargeBitmap *large_bitmap,
nat size );
-
-/* Similar to scavenge_large_bitmap(), but we don't write back the
- * pointers we get back from evacuate().
- */
-static void
-scavenge_large_srt_bitmap( StgLargeSRT *large_srt )
-{
- nat i, b, size;
- StgWord bitmap;
- StgClosure **p;
-
- b = 0;
- bitmap = large_srt->l.bitmap[b];
- size = (nat)large_srt->l.size;
- p = (StgClosure **)large_srt->srt;
- for (i = 0; i < size; ) {
- if ((bitmap & 1) != 0) {
- evacuate(p);
- }
- i++;
- p++;
- if (i % BITS_IN(W_) == 0) {
- b++;
- bitmap = large_srt->l.bitmap[b];
- } else {
- bitmap = bitmap >> 1;
- }
- }
-}
-
-/* evacuate the SRT. If srt_bitmap is zero, then there isn't an
- * srt field in the info table. That's ok, because we'll
- * never dereference it.
- */
-STATIC_INLINE void
-scavenge_srt (StgClosure **srt, nat srt_bitmap)
-{
- nat bitmap;
- StgClosure **p;
-
- bitmap = srt_bitmap;
- p = srt;
-
- if (bitmap == (StgHalfWord)(-1)) {
- scavenge_large_srt_bitmap( (StgLargeSRT *)srt );
- return;
- }
-
- while (bitmap != 0) {
- if ((bitmap & 1) != 0) {
-#if defined(__PIC__) && defined(mingw32_TARGET_OS)
- // Special-case to handle references to closures hiding out in DLLs, since
- // double indirections required to get at those. The code generator knows
- // which is which when generating the SRT, so it stores the (indirect)
- // reference to the DLL closure in the table by first adding one to it.
- // We check for this here, and undo the addition before evacuating it.
- //
- // If the SRT entry hasn't got bit 0 set, the SRT entry points to a
- // closure that's fixed at link-time, and no extra magic is required.
- if ( (unsigned long)(*srt) & 0x1 ) {
- evacuate(stgCast(StgClosure**,(stgCast(unsigned long, *srt) & ~0x1)));
- } else {
- evacuate(p);
- }
-#else
- evacuate(p);
+#if defined(THREADED_RTS) && !defined(PARALLEL_GC)
+# define evacuate(a) evacuate1(a)
+# define recordMutableGen_GC(a,b) recordMutableGen(a,b)
+# define scavenge_loop(a) scavenge_loop1(a)
+# define scavenge_mutable_list(g) scavenge_mutable_list1(g)
#endif
- }
- p++;
- bitmap = bitmap >> 1;
- }
-}
-
-
-STATIC_INLINE void
-scavenge_thunk_srt(const StgInfoTable *info)
-{
- StgThunkInfoTable *thunk_info;
-
- if (!major_gc) return;
-
- thunk_info = itbl_to_thunk_itbl(info);
- scavenge_srt((StgClosure **)GET_SRT(thunk_info), thunk_info->i.srt_bitmap);
-}
-
-STATIC_INLINE void
-scavenge_fun_srt(const StgInfoTable *info)
-{
- StgFunInfoTable *fun_info;
-
- if (!major_gc) return;
-
- fun_info = itbl_to_fun_itbl(info);
- scavenge_srt((StgClosure **)GET_FUN_SRT(fun_info), fun_info->i.srt_bitmap);
-}
/* -----------------------------------------------------------------------------
Scavenge a TSO.
}
/* -----------------------------------------------------------------------------
+ Scavenge SRTs
+ -------------------------------------------------------------------------- */
+
+/* Similar to scavenge_large_bitmap(), but we don't write back the
+ * pointers we get back from evacuate().
+ */
+static void
+scavenge_large_srt_bitmap( StgLargeSRT *large_srt )
+{
+ nat i, b, size;
+ StgWord bitmap;
+ StgClosure **p;
+
+ b = 0;
+ bitmap = large_srt->l.bitmap[b];
+ size = (nat)large_srt->l.size;
+ p = (StgClosure **)large_srt->srt;
+ for (i = 0; i < size; ) {
+ if ((bitmap & 1) != 0) {
+ evacuate(p);
+ }
+ i++;
+ p++;
+ if (i % BITS_IN(W_) == 0) {
+ b++;
+ bitmap = large_srt->l.bitmap[b];
+ } else {
+ bitmap = bitmap >> 1;
+ }
+ }
+}
+
+/* evacuate the SRT. If srt_bitmap is zero, then there isn't an
+ * srt field in the info table. That's ok, because we'll
+ * never dereference it.
+ */
+STATIC_INLINE void
+scavenge_srt (StgClosure **srt, nat srt_bitmap)
+{
+ nat bitmap;
+ StgClosure **p;
+
+ bitmap = srt_bitmap;
+ p = srt;
+
+ if (bitmap == (StgHalfWord)(-1)) {
+ scavenge_large_srt_bitmap( (StgLargeSRT *)srt );
+ return;
+ }
+
+ while (bitmap != 0) {
+ if ((bitmap & 1) != 0) {
+#if defined(__PIC__) && defined(mingw32_TARGET_OS)
+ // Special-case to handle references to closures hiding out in DLLs, since
+ // double indirections required to get at those. The code generator knows
+ // which is which when generating the SRT, so it stores the (indirect)
+ // reference to the DLL closure in the table by first adding one to it.
+ // We check for this here, and undo the addition before evacuating it.
+ //
+ // If the SRT entry hasn't got bit 0 set, the SRT entry points to a
+ // closure that's fixed at link-time, and no extra magic is required.
+ if ( (unsigned long)(*srt) & 0x1 ) {
+ evacuate(stgCast(StgClosure**,(stgCast(unsigned long, *srt) & ~0x1)));
+ } else {
+ evacuate(p);
+ }
+#else
+ evacuate(p);
+#endif
+ }
+ p++;
+ bitmap = bitmap >> 1;
+ }
+}
+
+
+STATIC_INLINE void
+scavenge_thunk_srt(const StgInfoTable *info)
+{
+ StgThunkInfoTable *thunk_info;
+
+ if (!major_gc) return;
+
+ thunk_info = itbl_to_thunk_itbl(info);
+ scavenge_srt((StgClosure **)GET_SRT(thunk_info), thunk_info->i.srt_bitmap);
+}
+
+STATIC_INLINE void
+scavenge_fun_srt(const StgInfoTable *info)
+{
+ StgFunInfoTable *fun_info;
+
+ if (!major_gc) return;
+
+ fun_info = itbl_to_fun_itbl(info);
+ scavenge_srt((StgClosure **)GET_FUN_SRT(fun_info), fun_info->i.srt_bitmap);
+}
+
+/* -----------------------------------------------------------------------------
+ Scavenge a block from the given scan pointer up to bd->free.
+
+ evac_step is set by the caller to be either zero (for a step in a
+ generation < N) or G where G is the generation of the step being
+ scavenged.
+
+ We sometimes temporarily change evac_step back to zero if we're
+ scavenging a mutable object where eager promotion isn't such a good
+ idea.
+ -------------------------------------------------------------------------- */
+
+static void
+scavenge_block (bdescr *bd)
+{
+ StgPtr p, q;
+ StgInfoTable *info;
+ step *saved_evac_step;
+ rtsBool saved_eager_promotion;
+ step_workspace *ws;
+
+ debugTrace(DEBUG_gc, "scavenging block %p (gen %d, step %d) @ %p",
+ bd->start, bd->gen_no, bd->step->no, bd->u.scan);
+
+ gct->scan_bd = bd;
+ gct->evac_step = bd->step;
+ saved_evac_step = gct->evac_step;
+ saved_eager_promotion = gct->eager_promotion;
+ gct->failed_to_evac = rtsFalse;
+
+ ws = &gct->steps[bd->step->abs_no];
+
+ p = bd->u.scan;
+
+ // we might be evacuating into the very object that we're
+ // scavenging, so we have to check the real bd->free pointer each
+ // time around the loop.
+ while (p < bd->free || (bd == ws->todo_bd && p < ws->todo_free)) {
+
+ ASSERT(LOOKS_LIKE_CLOSURE_PTR(p));
+ info = get_itbl((StgClosure *)p);
+
+ ASSERT(gct->thunk_selector_depth == 0);
+
+ q = p;
+ switch (info->type) {
+
+ case MVAR_CLEAN:
+ case MVAR_DIRTY:
+ {
+ StgMVar *mvar = ((StgMVar *)p);
+ gct->eager_promotion = rtsFalse;
+ evacuate((StgClosure **)&mvar->head);
+ evacuate((StgClosure **)&mvar->tail);
+ evacuate((StgClosure **)&mvar->value);
+ gct->eager_promotion = saved_eager_promotion;
+
+ if (gct->failed_to_evac) {
+ mvar->header.info = &stg_MVAR_DIRTY_info;
+ } else {
+ mvar->header.info = &stg_MVAR_CLEAN_info;
+ }
+ p += sizeofW(StgMVar);
+ break;
+ }
+
+ case FUN_2_0:
+ scavenge_fun_srt(info);
+ evacuate(&((StgClosure *)p)->payload[1]);
+ evacuate(&((StgClosure *)p)->payload[0]);
+ p += sizeofW(StgHeader) + 2;
+ break;
+
+ case THUNK_2_0:
+ scavenge_thunk_srt(info);
+ evacuate(&((StgThunk *)p)->payload[1]);
+ evacuate(&((StgThunk *)p)->payload[0]);
+ p += sizeofW(StgThunk) + 2;
+ break;
+
+ case CONSTR_2_0:
+ evacuate(&((StgClosure *)p)->payload[1]);
+ evacuate(&((StgClosure *)p)->payload[0]);
+ p += sizeofW(StgHeader) + 2;
+ break;
+
+ case THUNK_1_0:
+ scavenge_thunk_srt(info);
+ evacuate(&((StgThunk *)p)->payload[0]);
+ p += sizeofW(StgThunk) + 1;
+ break;
+
+ case FUN_1_0:
+ scavenge_fun_srt(info);
+ case CONSTR_1_0:
+ evacuate(&((StgClosure *)p)->payload[0]);
+ p += sizeofW(StgHeader) + 1;
+ break;
+
+ case THUNK_0_1:
+ scavenge_thunk_srt(info);
+ p += sizeofW(StgThunk) + 1;
+ break;
+
+ case FUN_0_1:
+ scavenge_fun_srt(info);
+ case CONSTR_0_1:
+ p += sizeofW(StgHeader) + 1;
+ break;
+
+ case THUNK_0_2:
+ scavenge_thunk_srt(info);
+ p += sizeofW(StgThunk) + 2;
+ break;
+
+ case FUN_0_2:
+ scavenge_fun_srt(info);
+ case CONSTR_0_2:
+ p += sizeofW(StgHeader) + 2;
+ break;
+
+ case THUNK_1_1:
+ scavenge_thunk_srt(info);
+ evacuate(&((StgThunk *)p)->payload[0]);
+ p += sizeofW(StgThunk) + 2;
+ break;
+
+ case FUN_1_1:
+ scavenge_fun_srt(info);
+ case CONSTR_1_1:
+ evacuate(&((StgClosure *)p)->payload[0]);
+ p += sizeofW(StgHeader) + 2;
+ break;
+
+ case FUN:
+ scavenge_fun_srt(info);
+ goto gen_obj;
+
+ case THUNK:
+ {
+ StgPtr end;
+
+ scavenge_thunk_srt(info);
+ end = (P_)((StgThunk *)p)->payload + info->layout.payload.ptrs;
+ for (p = (P_)((StgThunk *)p)->payload; p < end; p++) {
+ evacuate((StgClosure **)p);
+ }
+ p += info->layout.payload.nptrs;
+ break;
+ }
+
+ gen_obj:
+ case CONSTR:
+ case WEAK:
+ case STABLE_NAME:
+ {
+ StgPtr end;
+
+ end = (P_)((StgClosure *)p)->payload + info->layout.payload.ptrs;
+ for (p = (P_)((StgClosure *)p)->payload; p < end; p++) {
+ evacuate((StgClosure **)p);
+ }
+ p += info->layout.payload.nptrs;
+ break;
+ }
+
+ case BCO: {
+ StgBCO *bco = (StgBCO *)p;
+ evacuate((StgClosure **)&bco->instrs);
+ evacuate((StgClosure **)&bco->literals);
+ evacuate((StgClosure **)&bco->ptrs);
+ p += bco_sizeW(bco);
+ break;
+ }
+
+ case IND_PERM:
+ if (bd->gen_no != 0) {
+#ifdef PROFILING
+ // @LDV profiling
+ // No need to call LDV_recordDead_FILL_SLOP_DYNAMIC() because an
+ // IND_OLDGEN_PERM closure is larger than an IND_PERM closure.
+ LDV_recordDead((StgClosure *)p, sizeofW(StgInd));
+#endif
+ //
+ // Todo: maybe use SET_HDR() and remove LDV_RECORD_CREATE()?
+ //
+ SET_INFO(((StgClosure *)p), &stg_IND_OLDGEN_PERM_info);
+
+ // We pretend that p has just been created.
+ LDV_RECORD_CREATE((StgClosure *)p);
+ }
+ // fall through
+ case IND_OLDGEN_PERM:
+ evacuate(&((StgInd *)p)->indirectee);
+ p += sizeofW(StgInd);
+ break;
+
+ case MUT_VAR_CLEAN:
+ case MUT_VAR_DIRTY:
+ gct->eager_promotion = rtsFalse;
+ evacuate(&((StgMutVar *)p)->var);
+ gct->eager_promotion = saved_eager_promotion;
+
+ if (gct->failed_to_evac) {
+ ((StgClosure *)q)->header.info = &stg_MUT_VAR_DIRTY_info;
+ } else {
+ ((StgClosure *)q)->header.info = &stg_MUT_VAR_CLEAN_info;
+ }
+ p += sizeofW(StgMutVar);
+ break;
+
+ case CAF_BLACKHOLE:
+ case SE_CAF_BLACKHOLE:
+ case SE_BLACKHOLE:
+ case BLACKHOLE:
+ p += BLACKHOLE_sizeW();
+ break;
+
+ case THUNK_SELECTOR:
+ {
+ StgSelector *s = (StgSelector *)p;
+ evacuate(&s->selectee);
+ p += THUNK_SELECTOR_sizeW();
+ break;
+ }
+
+ // A chunk of stack saved in a heap object
+ case AP_STACK:
+ {
+ StgAP_STACK *ap = (StgAP_STACK *)p;
+
+ evacuate(&ap->fun);
+ scavenge_stack((StgPtr)ap->payload, (StgPtr)ap->payload + ap->size);
+ p = (StgPtr)ap->payload + ap->size;
+ break;
+ }
+
+ case PAP:
+ p = scavenge_PAP((StgPAP *)p);
+ break;
+
+ case AP:
+ p = scavenge_AP((StgAP *)p);
+ break;
+
+ case ARR_WORDS:
+ // nothing to follow
+ p += arr_words_sizeW((StgArrWords *)p);
+ break;
+
+ case MUT_ARR_PTRS_CLEAN:
+ case MUT_ARR_PTRS_DIRTY:
+ // follow everything
+ {
+ StgPtr next;
+
+ // We don't eagerly promote objects pointed to by a mutable
+ // array, but if we find the array only points to objects in
+ // the same or an older generation, we mark it "clean" and
+ // avoid traversing it during minor GCs.
+ gct->eager_promotion = rtsFalse;
+ next = p + mut_arr_ptrs_sizeW((StgMutArrPtrs*)p);
+ for (p = (P_)((StgMutArrPtrs *)p)->payload; p < next; p++) {
+ evacuate((StgClosure **)p);
+ }
+ gct->eager_promotion = saved_eager_promotion;
+
+ if (gct->failed_to_evac) {
+ ((StgClosure *)q)->header.info = &stg_MUT_ARR_PTRS_DIRTY_info;
+ } else {
+ ((StgClosure *)q)->header.info = &stg_MUT_ARR_PTRS_CLEAN_info;
+ }
+
+ gct->failed_to_evac = rtsTrue; // always put it on the mutable list.
+ break;
+ }
+
+ case MUT_ARR_PTRS_FROZEN:
+ case MUT_ARR_PTRS_FROZEN0:
+ // follow everything
+ {
+ StgPtr next;
+
+ next = p + mut_arr_ptrs_sizeW((StgMutArrPtrs*)p);
+ for (p = (P_)((StgMutArrPtrs *)p)->payload; p < next; p++) {
+ evacuate((StgClosure **)p);
+ }
+
+ // If we're going to put this object on the mutable list, then
+ // set its info ptr to MUT_ARR_PTRS_FROZEN0 to indicate that.
+ if (gct->failed_to_evac) {
+ ((StgClosure *)q)->header.info = &stg_MUT_ARR_PTRS_FROZEN0_info;
+ } else {
+ ((StgClosure *)q)->header.info = &stg_MUT_ARR_PTRS_FROZEN_info;
+ }
+ break;
+ }
+
+ case TSO:
+ {
+ StgTSO *tso = (StgTSO *)p;
+ scavengeTSO(tso);
+ p += tso_sizeW(tso);
+ break;
+ }
+
+ case TVAR_WATCH_QUEUE:
+ {
+ StgTVarWatchQueue *wq = ((StgTVarWatchQueue *) p);
+ gct->evac_step = 0;
+ evacuate((StgClosure **)&wq->closure);
+ evacuate((StgClosure **)&wq->next_queue_entry);
+ evacuate((StgClosure **)&wq->prev_queue_entry);
+ gct->evac_step = saved_evac_step;
+ gct->failed_to_evac = rtsTrue; // mutable
+ p += sizeofW(StgTVarWatchQueue);
+ break;
+ }
+
+ case TVAR:
+ {
+ StgTVar *tvar = ((StgTVar *) p);
+ gct->evac_step = 0;
+ evacuate((StgClosure **)&tvar->current_value);
+ evacuate((StgClosure **)&tvar->first_watch_queue_entry);
+ gct->evac_step = saved_evac_step;
+ gct->failed_to_evac = rtsTrue; // mutable
+ p += sizeofW(StgTVar);
+ break;
+ }
+
+ case TREC_HEADER:
+ {
+ StgTRecHeader *trec = ((StgTRecHeader *) p);
+ gct->evac_step = 0;
+ evacuate((StgClosure **)&trec->enclosing_trec);
+ evacuate((StgClosure **)&trec->current_chunk);
+ evacuate((StgClosure **)&trec->invariants_to_check);
+ gct->evac_step = saved_evac_step;
+ gct->failed_to_evac = rtsTrue; // mutable
+ p += sizeofW(StgTRecHeader);
+ break;
+ }
+
+ case TREC_CHUNK:
+ {
+ StgWord i;
+ StgTRecChunk *tc = ((StgTRecChunk *) p);
+ TRecEntry *e = &(tc -> entries[0]);
+ gct->evac_step = 0;
+ evacuate((StgClosure **)&tc->prev_chunk);
+ for (i = 0; i < tc -> next_entry_idx; i ++, e++ ) {
+ evacuate((StgClosure **)&e->tvar);
+ evacuate((StgClosure **)&e->expected_value);
+ evacuate((StgClosure **)&e->new_value);
+ }
+ gct->evac_step = saved_evac_step;
+ gct->failed_to_evac = rtsTrue; // mutable
+ p += sizeofW(StgTRecChunk);
+ break;
+ }
+
+ case ATOMIC_INVARIANT:
+ {
+ StgAtomicInvariant *invariant = ((StgAtomicInvariant *) p);
+ gct->evac_step = 0;
+ evacuate(&invariant->code);
+ evacuate((StgClosure **)&invariant->last_execution);
+ gct->evac_step = saved_evac_step;
+ gct->failed_to_evac = rtsTrue; // mutable
+ p += sizeofW(StgAtomicInvariant);
+ break;
+ }
+
+ case INVARIANT_CHECK_QUEUE:
+ {
+ StgInvariantCheckQueue *queue = ((StgInvariantCheckQueue *) p);
+ gct->evac_step = 0;
+ evacuate((StgClosure **)&queue->invariant);
+ evacuate((StgClosure **)&queue->my_execution);
+ evacuate((StgClosure **)&queue->next_queue_entry);
+ gct->evac_step = saved_evac_step;
+ gct->failed_to_evac = rtsTrue; // mutable
+ p += sizeofW(StgInvariantCheckQueue);
+ break;
+ }
+
+ default:
+ barf("scavenge: unimplemented/strange closure type %d @ %p",
+ info->type, p);
+ }
+
+ /*
+ * We need to record the current object on the mutable list if
+ * (a) It is actually mutable, or
+ * (b) It contains pointers to a younger generation.
+ * Case (b) arises if we didn't manage to promote everything that
+ * the current object points to into the current generation.
+ */
+ if (gct->failed_to_evac) {
+ gct->failed_to_evac = rtsFalse;
+ if (bd->gen_no > 0) {
+ recordMutableGen_GC((StgClosure *)q, &generations[bd->gen_no]);
+ }
+ }
+ }
+
+ if (p > bd->free) {
+ gct->copied += ws->todo_free - bd->free;
+ bd->free = p;
+ }
+
+ debugTrace(DEBUG_gc, " scavenged %ld bytes",
+ (unsigned long)((bd->free - bd->u.scan) * sizeof(W_)));
+
+ // update stats: this is a block that has been scavenged
+ gct->scanned += bd->free - bd->u.scan;
+ bd->u.scan = bd->free;
+
+ if (bd != ws->todo_bd) {
+ // we're not going to evac any more objects into
+ // this block, so push it now.
+ push_scanned_block(bd, ws);
+ }
+
+ gct->scan_bd = NULL;
+}
+/* -----------------------------------------------------------------------------
Scavenge everything on the mark stack.
This is slightly different from scavenge():
}
/* ----------------------------------------------------------------------------
- Scavenge a block
- ------------------------------------------------------------------------- */
-
-#undef PARALLEL_GC
-#include "Scav.c-inc"
-
-#ifdef THREADED_RTS
-#define PARALLEL_GC
-#include "Scav.c-inc"
-#endif
-
-/* ----------------------------------------------------------------------------
Look for work to do.
We look for the oldest step that has either a todo block that can
// scavenge everything up to the free pointer.
if (ws->todo_bd->u.scan < ws->todo_free)
{
- if (n_gc_threads == 1) {
- scavenge_block1(ws->todo_bd);
- } else {
- scavenge_block(ws->todo_bd);
- }
+ scavenge_block(ws->todo_bd);
did_something = rtsTrue;
break;
}
}
if ((bd = grab_todo_block(ws)) != NULL) {
- if (n_gc_threads == 1) {
- scavenge_block1(bd);
- } else {
- scavenge_block(bd);
- }
+ scavenge_block(bd);
did_something = rtsTrue;
break;
}
if (work_to_do) goto loop;
}
-rtsBool
-any_work (void)
-{
- int s;
- step_workspace *ws;
-
- gct->any_work++;
-
- write_barrier();
-
- // scavenge objects in compacted generation
- if (mark_stack_overflowed || oldgen_scan_bd != NULL ||
- (mark_stack_bdescr != NULL && !mark_stack_empty())) {
- return rtsTrue;
- }
-
- // Check for global work in any step. We don't need to check for
- // local work, because we have already exited scavenge_loop(),
- // which means there is no local work for this thread.
- for (s = total_steps-1; s >= 0; s--) {
- if (s == 0 && RtsFlags.GcFlags.generations > 1) {
- continue;
- }
- ws = &gct->steps[s];
- if (ws->todo_large_objects) return rtsTrue;
- if (ws->step->todos) return rtsTrue;
- }
-
- gct->no_work++;
-
- return rtsFalse;
-}
projects / ghc-hetmet.git / blobdiff