X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fincludes%2FClosures.h;h=d160ac5901687b0c6e59e6e9d850e9aedc08ebe9;hb=b61f70ce5ff947642c96b1ad980351691bb1e07a;hp=5f0b5709542fab2586fd4dacd9db4fd0c286ee75;hpb=b4623557bb3c8bec7232e4e68a8be8cf28fbbda6;p=ghc-hetmet.git diff --git a/ghc/includes/Closures.h b/ghc/includes/Closures.h index 5f0b570..d160ac5 100644 --- a/ghc/includes/Closures.h +++ b/ghc/includes/Closures.h @@ -1,7 +1,6 @@ /* ---------------------------------------------------------------------------- - * $Id: Closures.h,v 1.28 2001/10/03 13:57:42 simonmar Exp $ * - * (c) The GHC Team, 1998-1999 + * (c) The GHC Team, 1998-2004 * * Closures * @@ -20,18 +19,14 @@ -------------------------------------------------------------------------- */ typedef struct { - CostCentreStack *ccs; + CostCentreStack *ccs; + union { + struct _RetainerSet *rs; // Retainer Set + StgWord ldvw; // Lag/Drag/Void Word + } hp; } StgProfHeader; /* ----------------------------------------------------------------------------- - The parallel header - -------------------------------------------------------------------------- */ - -typedef struct { - /* StgWord ga; */ /* nope! global addresses are managed via a hash table */ -} StgParHeader; - -/* ----------------------------------------------------------------------------- The GranSim header -------------------------------------------------------------------------- */ @@ -40,29 +35,6 @@ typedef struct { } StgGranHeader; /* ----------------------------------------------------------------------------- - 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@. - -------------------------------------------------------------------------- */ - -typedef struct { - /* old: W_ updated; */ -} StgTickyHeader; - -/* ----------------------------------------------------------------------------- The full fixed-size closure header The size of the fixed header is the sum of the optional parts plus a single @@ -74,19 +46,11 @@ typedef struct { #ifdef PROFILING StgProfHeader prof; #endif -#ifdef PAR - StgParHeader par; -#endif #ifdef GRAN StgGranHeader gran; #endif -#ifdef TICKY_TICKY - StgTickyHeader ticky; -#endif } StgHeader; -#define FIXED_HS (sizeof(StgHeader)) - /* ----------------------------------------------------------------------------- Closure Types @@ -122,17 +86,21 @@ typedef struct { typedef struct { StgHeader header; - StgWord n_args; - StgClosure *fun; + 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; - StgClosure *payload[FLEXIBLE_ARRAY]; -} StgAP_UPD; + StgClosure *payload[FLEXIBLE_ARRAY]; // contains a chunk of *stack* +} StgAP_STACK; typedef struct { StgHeader header; @@ -171,37 +139,13 @@ typedef struct { StgMutClosure *mut_link; } StgMutVar; -typedef struct { - 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 */ -} StgBCO; - -/* - A collective typedef for all linkable stack frames i.e. - StgUpdateFrame, StgSeqFrame, StgCatchFrame -*/ -typedef struct _StgFrame { - StgHeader header; - struct _StgFrame *link; -} StgFrame; - 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; @@ -248,18 +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 { - const struct _StgInfoTable* info; - StgWord liveness; - StgWord ret_addr; - StgWord payload[FLEXIBLE_ARRAY]; + 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 { @@ -270,6 +308,93 @@ typedef struct { StgClosure* value; } StgMVar; +/* 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