+ IF_DEBUG(gc, statDescribeGens());
+}
+
+void
+exitStorage (void)
+{
+ stat_exit(calcAllocated());
+}
+
+/* -----------------------------------------------------------------------------
+ CAF management.
+
+ The entry code for every CAF does the following:
+
+ - builds a CAF_BLACKHOLE in the heap
+ - pushes an update frame pointing to the CAF_BLACKHOLE
+ - invokes UPD_CAF(), which:
+ - calls newCaf, below
+ - updates the CAF with a static indirection to the CAF_BLACKHOLE
+
+ Why do we build a BLACKHOLE in the heap rather than just updating
+ the thunk directly? It's so that we only need one kind of update
+ frame - otherwise we'd need a static version of the update frame too.
+
+ newCaf() does the following:
+
+ - it puts the CAF on the oldest generation's mut-once list.
+ This is so that we can treat the CAF as a root when collecting
+ younger generations.
+
+ For GHCI, we have additional requirements when dealing with CAFs:
+
+ - we must *retain* all dynamically-loaded CAFs ever entered,
+ just in case we need them again.
+ - we must be able to *revert* CAFs that have been evaluated, to
+ their pre-evaluated form.
+
+ To do this, we use an additional CAF list. When newCaf() is
+ called on a dynamically-loaded CAF, we add it to the CAF list
+ instead of the old-generation mutable list, and save away its
+ old info pointer (in caf->saved_info) for later reversion.
+
+ To revert all the CAFs, we traverse the CAF list and reset the
+ info pointer to caf->saved_info, then throw away the CAF list.
+ (see GC.c:revertCAFs()).
+
+ -- SDM 29/1/01
+
+ -------------------------------------------------------------------------- */
+
+void
+newCAF(StgClosure* caf)
+{
+ ACQUIRE_SM_LOCK;
+
+ if(keepCAFs)
+ {
+ // HACK:
+ // If we are in GHCi _and_ we are using dynamic libraries,
+ // then we can't redirect newCAF calls to newDynCAF (see below),
+ // so we make newCAF behave almost like newDynCAF.
+ // The dynamic libraries might be used by both the interpreted
+ // program and GHCi itself, so they must not be reverted.
+ // This also means that in GHCi with dynamic libraries, CAFs are not
+ // garbage collected. If this turns out to be a problem, we could
+ // do another hack here and do an address range test on caf to figure
+ // out whether it is from a dynamic library.
+ ((StgIndStatic *)caf)->saved_info = (StgInfoTable *)caf->header.info;
+ ((StgIndStatic *)caf)->static_link = caf_list;
+ caf_list = caf;
+ }
+ else
+ {
+ /* Put this CAF on the mutable list for the old generation.
+ * This is a HACK - the IND_STATIC closure doesn't really have
+ * a mut_link field, but we pretend it has - in fact we re-use
+ * the STATIC_LINK field for the time being, because when we
+ * come to do a major GC we won't need the mut_link field
+ * any more and can use it as a STATIC_LINK.
+ */
+ ((StgIndStatic *)caf)->saved_info = NULL;
+ recordMutableGen(caf, oldest_gen);
+ }
+
+ RELEASE_SM_LOCK;
+
+#ifdef PAR
+ /* If we are PAR or DIST then we never forget a CAF */
+ { globalAddr *newGA;
+ //debugBelch("<##> Globalising CAF %08x %s",caf,info_type(caf));
+ newGA=makeGlobal(caf,rtsTrue); /*given full weight*/
+ ASSERT(newGA);
+ }
+#endif /* PAR */
+}
+
+// An alternate version of newCaf which is used for dynamically loaded
+// object code in GHCi. In this case we want to retain *all* CAFs in
+// the object code, because they might be demanded at any time from an
+// expression evaluated on the command line.
+// Also, GHCi might want to revert CAFs, so we add these to the
+// revertible_caf_list.
+//
+// The linker hackily arranges that references to newCaf from dynamic
+// code end up pointing to newDynCAF.
+void
+newDynCAF(StgClosure *caf)
+{
+ ACQUIRE_SM_LOCK;
+
+ ((StgIndStatic *)caf)->saved_info = (StgInfoTable *)caf->header.info;
+ ((StgIndStatic *)caf)->static_link = revertible_caf_list;
+ revertible_caf_list = caf;
+
+ RELEASE_SM_LOCK;
+}
+
+/* -----------------------------------------------------------------------------
+ Nursery management.
+ -------------------------------------------------------------------------- */
+
+void
+allocNurseries( void )
+{
+#ifdef SMP
+ Capability *cap;
+ bdescr *bd;
+
+ g0s0->blocks = NULL;
+ g0s0->n_blocks = 0;
+ for (cap = free_capabilities; cap != NULL; cap = cap->link) {
+ cap->r.rNursery = allocNursery(NULL, RtsFlags.GcFlags.minAllocAreaSize);
+ cap->r.rCurrentNursery = cap->r.rNursery;
+ /* Set the back links to be equal to the Capability,
+ * so we can do slightly better informed locking.
+ */
+ for (bd = cap->r.rNursery; bd != NULL; bd = bd->link) {
+ bd->u.back = (bdescr *)cap;
+ }
+ }
+#else /* SMP */
+ g0s0->blocks = allocNursery(NULL, RtsFlags.GcFlags.minAllocAreaSize);
+ g0s0->n_blocks = RtsFlags.GcFlags.minAllocAreaSize;
+ g0s0->to_blocks = NULL;
+ g0s0->n_to_blocks = 0;
+ MainCapability.r.rNursery = g0s0->blocks;
+ MainCapability.r.rCurrentNursery = g0s0->blocks;
+ /* hp, hpLim, hp_bd, to_space etc. aren't used in G0S0 */
+#endif
+}
+
+void
+resetNurseries( void )
+{
+ bdescr *bd;
+#ifdef SMP
+ Capability *cap;
+
+ /* All tasks must be stopped */
+ ASSERT(n_free_capabilities == RtsFlags.ParFlags.nNodes);
+
+ for (cap = free_capabilities; cap != NULL; cap = cap->link) {
+ for (bd = cap->r.rNursery; bd; bd = bd->link) {
+ bd->free = bd->start;
+ ASSERT(bd->gen_no == 0);
+ ASSERT(bd->step == g0s0);
+ IF_DEBUG(sanity,memset(bd->start, 0xaa, BLOCK_SIZE));
+ }
+ cap->r.rCurrentNursery = cap->r.rNursery;
+ }
+#else
+ for (bd = g0s0->blocks; bd; bd = bd->link) {
+ bd->free = bd->start;
+ ASSERT(bd->gen_no == 0);
+ ASSERT(bd->step == g0s0);
+ IF_DEBUG(sanity,memset(bd->start, 0xaa, BLOCK_SIZE));
+ }
+ MainCapability.r.rNursery = g0s0->blocks;
+ MainCapability.r.rCurrentNursery = g0s0->blocks;
+#endif