X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fincludes%2FClosures.h;h=d5467928ed48a5bf8ee8e4a03bf352c5f6419d86;hb=423d477bfecd490de1449c59325c8776f91d7aac;hp=0f413b58a1ea1a465a5ac541a22eed03c5a0d8cc;hpb=db61851c5472bf565cd1da900b33d6e033fd743d;p=ghc-hetmet.git diff --git a/ghc/includes/Closures.h b/ghc/includes/Closures.h index 0f413b5..d546792 100644 --- a/ghc/includes/Closures.h +++ b/ghc/includes/Closures.h @@ -1,7 +1,6 @@ /* ---------------------------------------------------------------------------- - * $Id: Closures.h,v 1.29 2001/11/22 14:25:11 simonmar Exp $ * - * (c) The GHC Team, 1998-1999 + * (c) The GHC Team, 1998-2004 * * Closures * @@ -22,20 +21,12 @@ typedef struct { CostCentreStack *ccs; union { - RetainerSet *rs; // Retainer Set + 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 -------------------------------------------------------------------------- */ @@ -44,29 +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 @@ -78,19 +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 @@ -126,17 +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; @@ -175,37 +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; @@ -252,18 +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; + 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; - StgWord payload[FLEXIBLE_ARRAY]; + 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 {