X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Frts%2FGC.c;h=adb36cc21538f1e833e5004467ac58d67c06ee75;hb=423d477bfecd490de1449c59325c8776f91d7aac;hp=b90461ccb51612309ebce1552cb4f5dc5456b23e;hpb=d283bfc1b42cd6cf4a81c56d72a71bb451dfefc6;p=ghc-hetmet.git diff --git a/ghc/rts/GC.c b/ghc/rts/GC.c index b90461c..adb36cc 100644 --- a/ghc/rts/GC.c +++ b/ghc/rts/GC.c @@ -1,5 +1,5 @@ /* ----------------------------------------------------------------------------- - * $Id: GC.c,v 1.161 2003/10/22 15:00:59 simonmar Exp $ + * $Id: GC.c,v 1.168 2004/08/13 13:09:49 simonmar Exp $ * * (c) The GHC Team 1998-2003 * @@ -13,7 +13,8 @@ #include "RtsUtils.h" #include "Apply.h" #include "Storage.h" -#include "StoragePriv.h" +#include "LdvProfile.h" +#include "Updates.h" #include "Stats.h" #include "Schedule.h" #include "SchedAPI.h" // for ReverCAFs prototype @@ -23,7 +24,6 @@ #include "ProfHeap.h" #include "SchedAPI.h" #include "Weak.h" -#include "StablePriv.h" #include "Prelude.h" #include "ParTicky.h" // ToDo: move into Rts.h #include "GCCompact.h" @@ -44,7 +44,6 @@ #endif #include "RetainerProfile.h" -#include "LdvProfile.h" #include @@ -142,11 +141,13 @@ static void mark_root ( StgClosure **root ); // Use a register argument for evacuate, if available. #if __GNUC__ >= 2 -static StgClosure * evacuate (StgClosure *q) __attribute__((regparm(1))); +#define REGPARM1 __attribute__((regparm(1))) #else -static StgClosure * evacuate (StgClosure *q); +#define REGPARM1 #endif +REGPARM1 static StgClosure * evacuate (StgClosure *q); + static void zero_static_object_list ( StgClosure* first_static ); static void zero_mutable_list ( StgMutClosure *first ); @@ -190,31 +191,31 @@ static rtsBool mark_stack_overflowed; static bdescr *oldgen_scan_bd; static StgPtr oldgen_scan; -static inline rtsBool +STATIC_INLINE rtsBool mark_stack_empty(void) { return mark_sp == mark_stack; } -static inline rtsBool +STATIC_INLINE rtsBool mark_stack_full(void) { return mark_sp >= mark_splim; } -static inline void +STATIC_INLINE void reset_mark_stack(void) { mark_sp = mark_stack; } -static inline void +STATIC_INLINE void push_mark_stack(StgPtr p) { *mark_sp++ = p; } -static inline StgPtr +STATIC_INLINE StgPtr pop_mark_stack(void) { return *--mark_sp; @@ -445,11 +446,18 @@ GarbageCollect ( void (*get_roots)(evac_fn), rtsBool force_major_gc ) // don't forget to fill it with zeros! memset(bitmap, 0, bitmap_size); - // for each block in this step, point to its bitmap from the + // For each block in this step, point to its bitmap from the // block descriptor. for (bd=stp->blocks; bd != NULL; bd = bd->link) { bd->u.bitmap = bitmap; bitmap += BLOCK_SIZE_W / (sizeof(W_)*BITS_PER_BYTE); + + // Also at this point we set the BF_COMPACTED flag + // for this block. The invariant is that + // BF_COMPACTED is always unset, except during GC + // when it is set on those blocks which will be + // compacted. + bd->flags |= BF_COMPACTED; } } } @@ -576,17 +584,6 @@ GarbageCollect ( void (*get_roots)(evac_fn), rtsBool force_major_gc ) */ markStablePtrTable(mark_root); -#ifdef INTERPRETER - { - /* ToDo: To fix the caf leak, we need to make the commented out - * parts of this code do something sensible - as described in - * the CAF document. - */ - extern void markHugsObjects(void); - markHugsObjects(); - } -#endif - /* ------------------------------------------------------------------------- * Repeatedly scavenge all the areas we know about until there's no * more scavenging to be done. @@ -751,7 +748,7 @@ GarbageCollect ( void (*get_roots)(evac_fn), rtsBool force_major_gc ) // for a compacted step, just shift the new to-space // onto the front of the now-compacted existing blocks. for (bd = stp->to_blocks; bd != NULL; bd = bd->link) { - bd->flags &= ~BF_EVACUATED; // now from-space + bd->flags &= ~BF_EVACUATED; // now from-space } // tack the new blocks on the end of the existing blocks if (stp->blocks == NULL) { @@ -762,6 +759,11 @@ GarbageCollect ( void (*get_roots)(evac_fn), rtsBool force_major_gc ) if (next == NULL) { bd->link = stp->to_blocks; } + // NB. this step might not be compacted next + // time, so reset the BF_COMPACTED flags. + // They are set before GC if we're going to + // compact. (search for BF_COMPACTED above). + bd->flags &= ~BF_COMPACTED; } } // add the new blocks to the block tally @@ -771,7 +773,7 @@ GarbageCollect ( void (*get_roots)(evac_fn), rtsBool force_major_gc ) stp->blocks = stp->to_blocks; stp->n_blocks = stp->n_to_blocks; for (bd = stp->blocks; bd != NULL; bd = bd->link) { - bd->flags &= ~BF_EVACUATED; // now from-space + bd->flags &= ~BF_EVACUATED; // now from-space } } stp->to_blocks = NULL; @@ -1294,6 +1296,7 @@ traverse_weak_ptr_list(void) default: barf("traverse_weak_ptr_list"); + return rtsTrue; } } @@ -1374,7 +1377,7 @@ isAlive(StgClosure *p) } // check the mark bit for compacted steps - if (bd->step->is_compacted && is_marked((P_)p,bd)) { + if ((bd->flags & BF_COMPACTED) && is_marked((P_)p,bd)) { return p; } @@ -1413,19 +1416,19 @@ mark_root(StgClosure **root) *root = evacuate(*root); } -static __inline__ void +STATIC_INLINE void upd_evacuee(StgClosure *p, StgClosure *dest) { // Source object must be in from-space: ASSERT((Bdescr((P_)p)->flags & BF_EVACUATED) == 0); // not true: (ToDo: perhaps it should be) // ASSERT(Bdescr((P_)dest)->flags & BF_EVACUATED); - p->header.info = &stg_EVACUATED_info; + SET_INFO(p, &stg_EVACUATED_info); ((StgEvacuated *)p)->evacuee = dest; } -static __inline__ StgClosure * +STATIC_INLINE StgClosure * copy(StgClosure *src, nat size, step *stp) { P_ to, from, dest; @@ -1531,7 +1534,7 @@ copyPart(StgClosure *src, nat size_to_reserve, nat size_to_copy, step *stp) -------------------------------------------------------------------------- */ -static inline void +STATIC_INLINE void evacuate_large(StgPtr p) { bdescr *bd = Bdescr(p); @@ -1657,7 +1660,7 @@ mkMutCons(StgClosure *ptr, generation *gen) extra reads/writes than we save. -------------------------------------------------------------------------- */ -static StgClosure * +REGPARM1 static StgClosure * evacuate(StgClosure *q) { StgClosure *to; @@ -1699,7 +1702,7 @@ loop: /* If the object is in a step that we're compacting, then we * need to use an alternative evacuate procedure. */ - if (bd->step->is_compacted) { + if (bd->flags & BF_COMPACTED) { if (!is_marked((P_)q,bd)) { mark((P_)q,bd); if (mark_stack_full()) { @@ -2010,6 +2013,22 @@ loop: thunk is unchanged. -------------------------------------------------------------------------- */ +static inline rtsBool +is_to_space ( StgClosure *p ) +{ + bdescr *bd; + + bd = Bdescr((StgPtr)p); + if (HEAP_ALLOCED(p) && + ((bd->flags & BF_EVACUATED) + || ((bd->flags & BF_COMPACTED) && + is_marked((P_)p,bd)))) { + return rtsTrue; + } else { + return rtsFalse; + } +} + static StgClosure * eval_thunk_selector( nat field, StgSelector * p ) { @@ -2042,17 +2061,30 @@ selector_loop: // eval_thunk_selector(). There are various ways this could // happen: // - // - following an IND_STATIC + // 1. following an IND_STATIC // - // - when the old generation is compacted, the mark phase updates - // from-space pointers to be to-space pointers, and we can't - // reliably tell which we're following (eg. from an IND_STATIC). + // 2. when the old generation is compacted, the mark phase updates + // from-space pointers to be to-space pointers, and we can't + // reliably tell which we're following (eg. from an IND_STATIC). // - // So we use the block-descriptor test to find out if we're in - // to-space. + // 3. compacting GC again: if we're looking at a constructor in + // the compacted generation, it might point directly to objects + // in to-space. We must bale out here, otherwise doing the selection + // will result in a to-space pointer being returned. + // + // (1) is dealt with using a BF_EVACUATED test on the + // selectee. (2) and (3): we can tell if we're looking at an + // object in the compacted generation that might point to + // to-space objects by testing that (a) it is BF_COMPACTED, (b) + // the compacted generation is being collected, and (c) the + // object is marked. Only a marked object may have pointers that + // point to to-space objects, because that happens when + // scavenging. // - if (HEAP_ALLOCED(selectee) && - Bdescr((StgPtr)selectee)->flags & BF_EVACUATED) { + // The to-space test is now embodied in the in_to_space() inline + // function, as it is re-used below. + // + if (is_to_space(selectee)) { goto bale_out; } @@ -2070,9 +2102,21 @@ selector_loop: ASSERT(field < (StgWord32)(info->layout.payload.ptrs + info->layout.payload.nptrs)); - // ToDo: shouldn't we test whether this pointer is in - // to-space? - return selectee->payload[field]; + // Select the right field from the constructor, and check + // that the result isn't in to-space. It might be in + // to-space if, for example, this constructor contains + // pointers to younger-gen objects (and is on the mut-once + // list). + // + { + StgClosure *q; + q = selectee->payload[field]; + if (is_to_space(q)) { + goto bale_out; + } else { + return q; + } + } case IND: case IND_PERM: @@ -2116,15 +2160,15 @@ selector_loop: // For the purposes of LDV profiling, we have destroyed // the original selector thunk. SET_INFO(p, info_ptr); - LDV_recordDead_FILL_SLOP_DYNAMIC(selectee); + LDV_RECORD_DEAD_FILL_SLOP_DYNAMIC(selectee); #endif ((StgInd *)selectee)->indirectee = val; SET_INFO(selectee,&stg_IND_info); -#ifdef PROFILING + // For the purposes of LDV profiling, we have created an // indirection. - LDV_recordCreate(selectee); -#endif + LDV_RECORD_CREATE(selectee); + selectee = val; goto selector_loop; } @@ -2215,7 +2259,7 @@ scavenge_large_srt_bitmap( StgLargeSRT *large_srt ) * srt field in the info table. That's ok, because we'll * never dereference it. */ -static inline void +STATIC_INLINE void scavenge_srt (StgClosure **srt, nat srt_bitmap) { nat bitmap; @@ -2255,7 +2299,7 @@ scavenge_srt (StgClosure **srt, nat srt_bitmap) } -static inline void +STATIC_INLINE void scavenge_thunk_srt(const StgInfoTable *info) { StgThunkInfoTable *thunk_info; @@ -2264,16 +2308,16 @@ scavenge_thunk_srt(const StgInfoTable *info) scavenge_srt((StgClosure **)thunk_info->srt, thunk_info->i.srt_bitmap); } -static inline void +STATIC_INLINE void scavenge_fun_srt(const StgInfoTable *info) { StgFunInfoTable *fun_info; fun_info = itbl_to_fun_itbl(info); - scavenge_srt((StgClosure **)fun_info->srt, fun_info->i.srt_bitmap); + scavenge_srt((StgClosure **)fun_info->f.srt, fun_info->i.srt_bitmap); } -static inline void +STATIC_INLINE void scavenge_ret_srt(const StgInfoTable *info) { StgRetInfoTable *ret_info; @@ -2315,7 +2359,7 @@ scavengeTSO (StgTSO *tso) in PAPs. -------------------------------------------------------------------------- */ -static inline StgPtr +STATIC_INLINE StgPtr scavenge_arg_block (StgFunInfoTable *fun_info, StgClosure **args) { StgPtr p; @@ -2323,19 +2367,19 @@ scavenge_arg_block (StgFunInfoTable *fun_info, StgClosure **args) nat size; p = (StgPtr)args; - switch (fun_info->fun_type) { + switch (fun_info->f.fun_type) { case ARG_GEN: - bitmap = BITMAP_BITS(fun_info->bitmap); - size = BITMAP_SIZE(fun_info->bitmap); + bitmap = BITMAP_BITS(fun_info->f.bitmap); + size = BITMAP_SIZE(fun_info->f.bitmap); goto small_bitmap; case ARG_GEN_BIG: - size = ((StgLargeBitmap *)fun_info->bitmap)->size; - scavenge_large_bitmap(p, (StgLargeBitmap *)fun_info->bitmap, size); + size = ((StgLargeBitmap *)fun_info->f.bitmap)->size; + scavenge_large_bitmap(p, (StgLargeBitmap *)fun_info->f.bitmap, size); p += size; break; default: - bitmap = BITMAP_BITS(stg_arg_bitmaps[fun_info->fun_type]); - size = BITMAP_SIZE(stg_arg_bitmaps[fun_info->fun_type]); + bitmap = BITMAP_BITS(stg_arg_bitmaps[fun_info->f.fun_type]); + size = BITMAP_SIZE(stg_arg_bitmaps[fun_info->f.fun_type]); small_bitmap: while (size > 0) { if ((bitmap & 1) == 0) { @@ -2350,7 +2394,7 @@ scavenge_arg_block (StgFunInfoTable *fun_info, StgClosure **args) return p; } -static inline StgPtr +STATIC_INLINE StgPtr scavenge_PAP (StgPAP *pap) { StgPtr p; @@ -2364,12 +2408,12 @@ scavenge_PAP (StgPAP *pap) p = (StgPtr)pap->payload; size = pap->n_args; - switch (fun_info->fun_type) { + switch (fun_info->f.fun_type) { case ARG_GEN: - bitmap = BITMAP_BITS(fun_info->bitmap); + bitmap = BITMAP_BITS(fun_info->f.bitmap); goto small_bitmap; case ARG_GEN_BIG: - scavenge_large_bitmap(p, (StgLargeBitmap *)fun_info->bitmap, size); + scavenge_large_bitmap(p, (StgLargeBitmap *)fun_info->f.bitmap, size); p += size; break; case ARG_BCO: @@ -2377,7 +2421,7 @@ scavenge_PAP (StgPAP *pap) p += size; break; default: - bitmap = BITMAP_BITS(stg_arg_bitmaps[fun_info->fun_type]); + bitmap = BITMAP_BITS(stg_arg_bitmaps[fun_info->f.fun_type]); small_bitmap: size = pap->n_args; while (size > 0) { @@ -2563,14 +2607,12 @@ scavenge(step *stp) LDV_recordDead((StgClosure *)p, sizeofW(StgInd)); #endif // - // Todo: maybe use SET_HDR() and remove LDV_recordCreate()? + // Todo: maybe use SET_HDR() and remove LDV_RECORD_CREATE()? // SET_INFO(((StgClosure *)p), &stg_IND_OLDGEN_PERM_info); -#ifdef PROFILING - // @LDV profiling + // We pretend that p has just been created. - LDV_recordCreate((StgClosure *)p); -#endif + LDV_RECORD_CREATE((StgClosure *)p); } // fall through case IND_OLDGEN_PERM: @@ -2666,6 +2708,11 @@ scavenge(step *stp) { StgPtr next; + // Set the mut_link field to NULL, so that we will put this + // array back on the mutable list if it is subsequently thawed + // by unsafeThaw#. + ((StgMutArrPtrs*)p)->mut_link = NULL; + next = p + mut_arr_ptrs_sizeW((StgMutArrPtrs*)p); for (p = (P_)((StgMutArrPtrs *)p)->payload; p < next; p++) { (StgClosure *)*p = evacuate((StgClosure *)*p); @@ -2674,11 +2721,6 @@ scavenge(step *stp) // false, but that breaks some assumptions (eg. every // closure on the mutable list is supposed to have the MUT // flag set, and MUT_ARR_PTRS_FROZEN doesn't). - - // Set the mut_link field to NULL, so that we will put this - // array back on the mutable list if it is subsequently thawed - // by unsafeThaw#. - ((StgMutArrPtrs*)p)->mut_link = NULL; break; } @@ -2981,14 +3023,15 @@ linear_scan: { StgPtr next; - next = p + mut_arr_ptrs_sizeW((StgMutArrPtrs*)p); - for (p = (P_)((StgMutArrPtrs *)p)->payload; p < next; p++) { - (StgClosure *)*p = evacuate((StgClosure *)*p); - } // Set the mut_link field to NULL, so that we will put this // array on the mutable list if it is subsequently thawed // by unsafeThaw#. ((StgMutArrPtrs*)p)->mut_link = NULL; + + next = p + mut_arr_ptrs_sizeW((StgMutArrPtrs*)p); + for (p = (P_)((StgMutArrPtrs *)p)->payload; p < next; p++) { + (StgClosure *)*p = evacuate((StgClosure *)*p); + } break; } @@ -3207,14 +3250,15 @@ scavenge_one(StgPtr p) // follow everything StgPtr next; - next = p + mut_arr_ptrs_sizeW((StgMutArrPtrs*)p); - for (p = (P_)((StgMutArrPtrs *)p)->payload; p < next; p++) { - (StgClosure *)*p = evacuate((StgClosure *)*p); - } // Set the mut_link field to NULL, so that we will put this // array on the mutable list if it is subsequently thawed // by unsafeThaw#. ((StgMutArrPtrs*)p)->mut_link = NULL; + + next = p + mut_arr_ptrs_sizeW((StgMutArrPtrs*)p); + for (p = (P_)((StgMutArrPtrs *)p)->payload; p < next; p++) { + (StgClosure *)*p = evacuate((StgClosure *)*p); + } break; } @@ -3671,7 +3715,7 @@ scavenge_large_bitmap( StgPtr p, StgLargeBitmap *large_bitmap, nat size ) } } -static inline StgPtr +STATIC_INLINE StgPtr scavenge_small_bitmap (StgPtr p, nat size, StgWord bitmap) { while (size > 0) { @@ -3771,16 +3815,16 @@ scavenge_stack(StgPtr p, StgPtr stack_end) dyn = ((StgRetDyn *)p)->liveness; // traverse the bitmap first - bitmap = GET_LIVENESS(dyn); + bitmap = RET_DYN_LIVENESS(dyn); p = (P_)&((StgRetDyn *)p)->payload[0]; size = RET_DYN_BITMAP_SIZE; p = scavenge_small_bitmap(p, size, bitmap); // skip over the non-ptr words - p += GET_NONPTRS(dyn) + RET_DYN_NONPTR_REGS_SIZE; + p += RET_DYN_NONPTRS(dyn) + RET_DYN_NONPTR_REGS_SIZE; // follow the ptr words - for (size = GET_PTRS(dyn); size > 0; size--) { + for (size = RET_DYN_PTRS(dyn); size > 0; size--) { (StgClosure *)*p = evacuate((StgClosure *)*p); p++; } @@ -3891,7 +3935,7 @@ revertCAFs( void ) for (c = (StgIndStatic *)caf_list; c != NULL; c = (StgIndStatic *)c->static_link) { - c->header.info = c->saved_info; + SET_INFO(c, c->saved_info); c->saved_info = NULL; // could, but not necessary: c->static_link = NULL; } @@ -4012,11 +4056,9 @@ threadLazyBlackHole(StgTSO *tso) LDV_recordDead_FILL_SLOP_DYNAMIC((StgClosure *)bh); #endif SET_INFO(bh,&stg_BLACKHOLE_info); -#ifdef PROFILING - // @LDV profiling + // We pretend that bh has just been created. - LDV_recordCreate(bh); -#endif + LDV_RECORD_CREATE(bh); } frame = (StgClosure *) ((StgUpdateFrame *)frame + 1); @@ -4159,12 +4201,11 @@ threadSqueezeStack(StgTSO *tso) // We pretend that bh is now dead. LDV_recordDead_FILL_SLOP_DYNAMIC((StgClosure *)bh); #endif - // Todo: maybe use SET_HDR() and remove LDV_recordCreate()? + // Todo: maybe use SET_HDR() and remove LDV_RECORD_CREATE()? SET_INFO(bh,&stg_BLACKHOLE_info); -#ifdef PROFILING + // We pretend that bh has just been created. - LDV_recordCreate(bh); -#endif + LDV_RECORD_CREATE(bh); } prev_was_update_frame = rtsTrue; @@ -4219,20 +4260,20 @@ done_traversing: void *gap_start, *next_gap_start, *gap_end; nat chunk_size; - next_gap_start = (void *)gap + sizeof(StgUpdateFrame); + next_gap_start = (void *)((unsigned char*)gap + sizeof(StgUpdateFrame)); sp = next_gap_start; while ((StgPtr)gap > tso->sp) { // we're working in *bytes* now... gap_start = next_gap_start; - gap_end = gap_start - gap->gap_size * sizeof(W_); + gap_end = (void*) ((unsigned char*)gap_start - gap->gap_size * sizeof(W_)); gap = gap->next_gap; - next_gap_start = (void *)gap + sizeof(StgUpdateFrame); + next_gap_start = (void *)((unsigned char*)gap + sizeof(StgUpdateFrame)); - chunk_size = gap_end - next_gap_start; - sp -= chunk_size; + chunk_size = (unsigned char*)gap_end - (unsigned char*)next_gap_start; + (unsigned char*)sp -= chunk_size; memmove(sp, next_gap_start, chunk_size); } @@ -4293,7 +4334,7 @@ printMutableList(generation *gen) fputc('\n', stderr); } -static inline rtsBool +STATIC_INLINE rtsBool maybeLarge(StgClosure *closure) { StgInfoTable *info = get_itbl(closure);