X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fincludes%2FClosures.h;h=d160ac5901687b0c6e59e6e9d850e9aedc08ebe9;hb=b61f70ce5ff947642c96b1ad980351691bb1e07a;hp=cb2270a9a0b289b2d82be0435855ce0273d7eeda;hpb=b75f6d049a3bad4c964087bd810ccca435912ae9;p=ghc-hetmet.git diff --git a/ghc/includes/Closures.h b/ghc/includes/Closures.h index cb2270a..d160ac5 100644 --- a/ghc/includes/Closures.h +++ b/ghc/includes/Closures.h @@ -1,7 +1,6 @@ /* ---------------------------------------------------------------------------- - * $Id: Closures.h,v 1.11 1999/03/09 14:24:46 sewardj Exp $ * - * (c) The GHC Team, 1998-1999 + * (c) The GHC Team, 1998-2004 * * Closures * @@ -19,71 +18,22 @@ The profiling header -------------------------------------------------------------------------- */ -#ifdef PROFILING - typedef struct { - CostCentreStack *ccs; + CostCentreStack *ccs; + union { + struct _RetainerSet *rs; // Retainer Set + StgWord ldvw; // Lag/Drag/Void Word + } hp; } StgProfHeader; -#else /* !PROFILING */ - -typedef struct { - /* empty */ -} StgProfHeader; - -#endif /* PROFILING */ - /* ----------------------------------------------------------------------------- - The parallel header + The GranSim header -------------------------------------------------------------------------- */ -#ifdef GRAN - -typedef struct { - W_ procs; -} StgGranHeader; - -#else /* !PAR */ - typedef struct { - /* empty */ + StgWord procs; /* bitmask indicating on which PEs this closure resides */ } StgGranHeader; -#endif /* PAR */ - -/* ----------------------------------------------------------------------------- - The ticky-ticky header - - Comment from old Ticky.h: - - This is used to record if a closure has been updated but not yet - entered. It is set when the closure is updated and cleared when - subsequently entered. - - NB: It is {\em not} an ``entry count'', it is an - ``entries-after-update count.'' - - The commoning up of @CONST@, @CHARLIKE@ and @INTLIKE@ closures is - turned off(?) if this is required. This has only been done for 2s - collection. It is done using a nasty hack which defines the - @_Evacuate@ and @_Scavenge@ code for @CONST@, @CHARLIKE@ and @INTLIKE@ - info tables to be @_Evacuate_1@ and @_Scavenge_1_0@. - -------------------------------------------------------------------------- */ - -#ifdef TICKY - -typedef struct { - W_ updated; -} StgTickyHeader; - -#else /* !TICKY */ - -typedef struct { - /* empty */ -} StgTickyHeader; - -#endif /* TICKY */ - /* ----------------------------------------------------------------------------- The full fixed-size closure header @@ -97,15 +47,10 @@ typedef struct { StgProfHeader prof; #endif #ifdef GRAN - StgGranHeader par; -#endif -#ifdef TICKY - StgTickyHeader ticky; + StgGranHeader gran; #endif } StgHeader; -#define FIXED_HS (sizeof(StgHeader)) - /* ----------------------------------------------------------------------------- Closure Types @@ -116,10 +61,10 @@ typedef struct { /* All closures follow the generic format */ -typedef struct StgClosure_ { +struct StgClosure_ { StgHeader header; - struct StgClosure_ *payload[0]; -} StgClosure; + struct StgClosure_ *payload[FLEXIBLE_ARRAY]; +}; /* What a stroke of luck - all our mutable closures follow the same * basic layout, with the mutable link field as the second field after @@ -129,9 +74,9 @@ typedef struct StgClosure_ { typedef struct StgMutClosure_ { StgHeader header; - StgPtr *padding; + StgWord padding; struct StgMutClosure_ *mut_link; - struct StgClosure_ *payload[0]; + struct StgClosure_ *payload[FLEXIBLE_ARRAY]; } StgMutClosure; typedef struct { @@ -141,26 +86,21 @@ typedef struct { typedef struct { StgHeader header; - StgWord n_args; - StgClosure *fun; - StgPtr payload[0]; + StgHalfWord arity; /* zero if it is an AP */ + StgHalfWord n_args; + StgClosure *fun; /* really points to a fun */ + StgClosure *payload[FLEXIBLE_ARRAY]; } StgPAP; +// AP closures have the same layout, for convenience +typedef StgPAP StgAP; + typedef struct { StgHeader header; - StgWord n_args; + StgWord size; // number of words in payload StgClosure *fun; - StgPtr payload[0]; -} StgAP_UPD; - -typedef struct { - StgHeader header; - StgWord n_ptrs; - StgWord n_words; - StgWord n_instrs; - StgWord stgexpr; - StgPtr payload[0]; -} StgBCO; + StgClosure *payload[FLEXIBLE_ARRAY]; // contains a chunk of *stack* +} StgAP_STACK; typedef struct { StgHeader header; @@ -174,36 +114,23 @@ typedef struct { } StgIndOldGen; typedef struct { - StgHeader header; - StgClosure *indirectee; - StgClosure *static_link; -} StgIndStatic; - -typedef struct StgCAF_ { StgHeader header; - StgClosure *body; - StgMutClosure *mut_link; - StgClosure *value; - struct StgCAF_ *link; -} StgCAF; - -typedef struct { - StgHeader header; - struct StgTSO_ *blocking_queue; - StgMutClosure *mut_link; -} StgBlockingQueue; + StgClosure *indirectee; + StgClosure *static_link; + struct _StgInfoTable *saved_info; +} StgIndStatic; typedef struct { StgHeader header; StgWord words; - StgWord payload[0]; + StgWord payload[FLEXIBLE_ARRAY]; } StgArrWords; typedef struct { StgHeader header; StgWord ptrs; StgMutClosure *mut_link; /* mutable list */ - StgClosure *payload[0]; + StgClosure *payload[FLEXIBLE_ARRAY]; } StgMutArrPtrs; typedef struct { @@ -214,18 +141,12 @@ typedef struct { typedef struct _StgUpdateFrame { StgHeader header; - struct _StgUpdateFrame *link; StgClosure *updatee; } StgUpdateFrame; typedef struct { StgHeader header; - struct _StgUpdateFrame *link; -} StgSeqFrame; - -typedef struct { - StgHeader header; - struct _StgUpdateFrame *link; + StgInt exceptions_blocked; StgClosure *handler; } StgCatchFrame; @@ -257,7 +178,7 @@ typedef struct _StgStableName { StgHeader header; StgWord sn; } StgStableName; - + typedef struct _StgWeak { /* Weak v */ StgHeader header; StgClosure *key; @@ -271,18 +192,112 @@ typedef struct _StgDeadWeak { /* Weak v */ struct _StgWeak *link; } StgDeadWeak; -/* Dynamic stack frames - these have a liveness mask in the object - * itself, rather than in the info table. Useful for generic heap - * check code. +/* Byte code objects. These are fixed size objects with pointers to + * four arrays, designed so that a BCO can be easily "re-linked" to + * other BCOs, to facilitate GHC's intelligent recompilation. The + * array of instructions is static and not re-generated when the BCO + * is re-linked, but the other 3 arrays will be regenerated. + * + * A BCO represents either a function or a stack frame. In each case, + * it needs a bitmap to describe to the garbage collector the + * pointerhood of its arguments/free variables respectively, and in + * the case of a function it also needs an arity. These are stored + * directly in the BCO, rather than in the instrs array, for two + * reasons: + * (a) speed: we need to get at the bitmap info quickly when + * the GC is examining APs and PAPs that point to this BCO + * (b) a subtle interaction with the compacting GC. In compacting + * GC, the info that describes the size/layout of a closure + * cannot be in an object more than one level of indirection + * away from the current object, because of the order in + * which pointers are updated to point to their new locations. */ - + typedef struct { - StgHeader header; - StgWord liveness; - StgWord ret_addr; - StgWord payload[0]; + StgHeader header; + StgArrWords *instrs; // a pointer to an ArrWords + StgArrWords *literals; // a pointer to an ArrWords + StgMutArrPtrs *ptrs; // a pointer to a MutArrPtrs + StgArrWords *itbls; // a pointer to an ArrWords + StgHalfWord arity; // arity of this BCO + StgHalfWord size; // size of this BCO (in words) + StgWord bitmap[FLEXIBLE_ARRAY]; // an StgLargeBitmap +} StgBCO; + +#define BCO_BITMAP(bco) ((StgLargeBitmap *)((StgBCO *)(bco))->bitmap) +#define BCO_BITMAP_SIZE(bco) (BCO_BITMAP(bco)->size) +#define BCO_BITMAP_BITS(bco) (BCO_BITMAP(bco)->bitmap) +#define BCO_BITMAP_SIZEW(bco) ((BCO_BITMAP_SIZE(bco) + BITS_IN(StgWord) - 1) \ + / BITS_IN(StgWord)) + +/* ----------------------------------------------------------------------------- + Dynamic stack frames for generic heap checks. + + These generic heap checks are slow, but have the advantage of being + usable in a variety of situations. + + The one restriction is that any relevant SRTs must already be pointed + to from the stack. The return address doesn't need to have an info + table attached: hence it can be any old code pointer. + + The liveness mask contains a 1 at bit n, if register Rn contains a + non-pointer. The contents of all 8 vanilla registers are always saved + on the stack; the liveness mask tells the GC which ones contain + pointers. + + Good places to use a generic heap check: + + - case alternatives (the return address with an SRT is already + on the stack). + + - primitives (no SRT required). + + The stack frame layout for a RET_DYN is like this: + + some pointers |-- RET_DYN_PTRS(liveness) words + some nonpointers |-- RET_DYN_NONPTRS(liveness) words + + L1 \ + D1-2 |-- RET_DYN_NONPTR_REGS_SIZE words + F1-4 / + + R1-8 |-- RET_DYN_BITMAP_SIZE words + + return address \ + liveness mask |-- StgRetDyn structure + stg_gen_chk_info / + + we assume that the size of a double is always 2 pointers (wasting a + word when it is only one pointer, but avoiding lots of #ifdefs). + + See Liveness.h for the macros (RET_DYN_PTRS() etc.). + + NOTE: if you change the layout of RET_DYN stack frames, then you + might also need to adjust the value of RESERVED_STACK_WORDS in + Constants.h. + -------------------------------------------------------------------------- */ + +typedef struct { + const struct _StgInfoTable* info; + StgWord liveness; + StgWord ret_addr; + StgClosure * payload[FLEXIBLE_ARRAY]; } StgRetDyn; +/* A function return stack frame: used when saving the state for a + * garbage collection at a function entry point. The function + * arguments are on the stack, and we also save the function (its + * info table describes the pointerhood of the arguments). + * + * The stack frame size is also cached in the frame for convenience. + */ +typedef struct { + const struct _StgInfoTable* info; + StgWord size; + StgClosure * fun; + StgClosure * payload[FLEXIBLE_ARRAY]; +} StgRetFun; + /* Concurrent communication objects */ typedef struct { @@ -293,12 +308,169 @@ typedef struct { StgClosure* value; } StgMVar; -/* Parallel FETCH_ME closures */ -#ifdef PAR +/* STM data structures + * + * StgTVar defines the only type that can be updated through the STM + * interface. + * + * Note that various optimisations may be possible in order to use less + * space for these data structures at the cost of more complexity in the + * implementation: + * + * - In StgTVar, current_value and first_wait_queue_entry could be held in + * the same field: if any thread is waiting then its expected_value for + * the tvar is the current value. + * + * - In StgTRecHeader, it might be worthwhile having separate chunks + * of read-only and read-write locations. This would save a + * new_value field in the read-only locations. + */ + +typedef struct StgTVarWaitQueue_ { + StgHeader header; + struct StgTSO_ *waiting_tso; + StgMutClosure *mut_link; + struct StgTVarWaitQueue_ *next_queue_entry; + struct StgTVarWaitQueue_ *prev_queue_entry; +} StgTVarWaitQueue; + +typedef struct { + StgHeader header; + StgClosure *current_value; + StgMutClosure *mut_link; + StgTVarWaitQueue *first_wait_queue_entry; +} StgTVar; + +// new_value == expected_value for read-only accesses +// new_value is a StgTVarWaitQueue entry when trec in state TREC_WAITING +typedef struct { + StgTVar *tvar; + StgClosure *expected_value; + StgClosure *new_value; +} TRecEntry; + +#define TREC_CHUNK_NUM_ENTRIES 256 + +typedef struct StgTRecChunk_ { + StgHeader header; + struct StgTRecChunk_ *prev_chunk; + StgMutClosure *mut_link; + StgWord next_entry_idx; + TRecEntry entries[TREC_CHUNK_NUM_ENTRIES]; +} StgTRecChunk; + +typedef enum { + TREC_ACTIVE, // Transaction in progress, outcome undecided + TREC_CANNOT_COMMIT, // Transaction in progress, inconsistent writes performed + TREC_MUST_ABORT, // Transaction in progress, inconsistent / out of date reads + TREC_COMMITTED, // Transaction has committed, now updating tvars + TREC_ABORTED, // Transaction has aborted, now reverting tvars + TREC_WAITING, // Transaction currently waiting +} TRecState; + +typedef struct StgTRecHeader_ { + StgHeader header; + TRecState state; + StgMutClosure *mut_link; + struct StgTRecHeader_ *enclosing_trec; + StgTRecChunk *current_chunk; +} StgTRecHeader; + +typedef struct { + StgHeader header; + StgBool waiting; + StgClosure *code; +} StgAtomicallyFrame; + +typedef struct { + StgHeader header; + StgClosure *handler; +} StgCatchSTMFrame; + typedef struct { + StgHeader header; + StgBool running_alt_code; + StgClosure *first_code; + StgClosure *alt_code; + StgTRecHeader *first_code_trec; +} StgCatchRetryFrame; + +#if defined(PAR) || defined(GRAN) +/* + StgBlockingQueueElement is a ``collective type'' representing the types + of closures that can be found on a blocking queue: StgTSO, StgRBHSave, + StgBlockedFetch. (StgRBHSave can only appear at the end of a blocking + queue). Logically, this is a union type, but defining another struct + with a common layout is easier to handle in the code (same as for + StgMutClosures). + Note that in the standard setup only StgTSOs can be on a blocking queue. + This is one of the main reasons for slightly different code in files + such as Schedule.c. +*/ +typedef struct StgBlockingQueueElement_ { + StgHeader header; + struct StgBlockingQueueElement_ *link; /* next elem in BQ */ + StgMutClosure *mut_link; /* next elem in mutable list */ + struct StgClosure_ *payload[FLEXIBLE_ARRAY];/* contents of the closure */ +} StgBlockingQueueElement; + +/* only difference to std code is type of the elem in the BQ */ +typedef struct StgBlockingQueue_ { + StgHeader header; + struct StgBlockingQueueElement_ *blocking_queue; /* start of the BQ */ + StgMutClosure *mut_link; /* next elem in mutable list */ +} StgBlockingQueue; + +/* this closure is hanging at the end of a blocking queue in (see RBH.c) */ +typedef struct StgRBHSave_ { StgHeader header; - void *ga; /* type globalAddr is abstract here */ + StgClosure *payload[FLEXIBLE_ARRAY]; /* 2 words ripped out of the guts of the */ +} StgRBHSave; /* closure holding the blocking queue */ + +typedef struct StgRBH_ { + StgHeader header; + struct StgBlockingQueueElement_ *blocking_queue; /* start of the BQ */ + StgMutClosure *mut_link; /* next elem in mutable list */ +} StgRBH; + +#else + +typedef struct StgBlockingQueue_ { + StgHeader header; + struct StgTSO_ *blocking_queue; + StgMutClosure *mut_link; +} StgBlockingQueue; + +#endif + +#if defined(PAR) +/* global indirections aka FETCH_ME closures */ +typedef struct StgFetchMe_ { + StgHeader header; + globalAddr *ga; /* ptr to unique id for a closure */ + StgMutClosure *mut_link; /* next elem in mutable list */ } StgFetchMe; + +/* same contents as an ordinary StgBlockingQueue */ +typedef struct StgFetchMeBlockingQueue_ { + StgHeader header; + struct StgBlockingQueueElement_ *blocking_queue; /* start of the BQ */ + StgMutClosure *mut_link; /* next elem in mutable list */ +} StgFetchMeBlockingQueue; + +/* This is an entry in a blocking queue. It indicates a fetch request from a + TSO on another PE demanding the value of this closur. Note that a + StgBlockedFetch can only occur in a BQ. Once the node is evaluated and + updated with the result, the result will be sent back (the PE is encoded + in the globalAddr) and the StgBlockedFetch closure will be nuked. +*/ +typedef struct StgBlockedFetch_ { + StgHeader header; + struct StgBlockingQueueElement_ *link; /* next elem in the BQ */ + StgMutClosure *mut_link; /* next elem in mutable list */ + StgClosure *node; /* node to fetch */ + globalAddr ga; /* where to send the result to */ +} StgBlockedFetch; /* NB: not just a ptr to a GA */ #endif #endif /* CLOSURES_H */