/* ----------------------------------------------------------------------------
- * $Id: InfoTables.h,v 1.31 2003/11/14 09:27:00 stolz Exp $
*
* (c) The GHC Team, 1998-2002
*
#if 0 && (defined(PAR) || defined(GRAN))
-// CURRENTLY UNUSED
-// ToDo: use this in StgInfoTable (mutually recursive) -- HWL
+/* CURRENTLY UNUSED
+ ToDo: use this in StgInfoTable (mutually recursive) -- HWL */
typedef struct {
StgInfoTable *rbh_infoptr; /* infoptr to the RBH */
# endif
/* see ParallelRts.h */
-// EXTFUN(RBH_entry);
-//StgClosure *convertToRBH(StgClosure *closure);
-//#if defined(GRAN)
-//void convertFromRBH(StgClosure *closure);
-//#elif defined(PAR)
-//void convertToFetchMe(StgPtr closure, globalAddr *ga);
-//#endif
+/*
+EXTFUN(RBH_entry);
+StgClosure *convertToRBH(StgClosure *closure);
+#if defined(GRAN)
+void convertFromRBH(StgClosure *closure);
+#elif defined(PAR)
+void convertToFetchMe(StgPtr closure, globalAddr *ga);
+#endif
+*/
#endif
/* -----------------------------------------------------------------------------
Ticky info
- -------------------------------------------------------------------------- */
-#if defined(SUPPORTS_EMPTY_STRUCTS)
-typedef struct {
- /* empty */
-} StgTickyInfo;
-#endif
+ There is no ticky-specific stuff in an info table at this time.
+ -------------------------------------------------------------------------- */
/* -----------------------------------------------------------------------------
Debugging info
#else /* !DEBUG_CLOSURE */
-# if defined(SUPPORTS_EMPTY_STRUCTS)
-typedef struct StgDebugInfo {
- /* empty */
-} StgDebugInfo;
-# endif
+/* There is no DEBUG-specific stuff in an info table at this time. */
#endif /* DEBUG_CLOSURE */
(usually on the stack) to the garbage collector. The two primary
uses are for stack frames, and functions (where we need to describe
the layout of a PAP to the GC).
+
+ In these bitmaps: 0 == ptr, 1 == non-ptr.
-------------------------------------------------------------------------- */
/*
- Small bitmaps: for a small bitmap, we store the size and bitmap in
- the same word, using the following macros. If the bitmap doesn't
- fit in a single word, we use a pointer to an StgLargeBitmap below.
-*/
+ * Small bitmaps: for a small bitmap, we store the size and bitmap in
+ * the same word, using the following macros. If the bitmap doesn't
+ * fit in a single word, we use a pointer to an StgLargeBitmap below.
+ */
#define MK_SMALL_BITMAP(size,bits) (((bits)<<BITMAP_BITS_SHIFT) | (size))
#define BITMAP_SIZE(bitmap) ((bitmap) & BITMAP_SIZE_MASK)
#define BITMAP_BITS(bitmap) ((bitmap) >> BITMAP_BITS_SHIFT)
/*
- A large bitmap.
-*/
+ * A large bitmap.
+ */
typedef struct {
StgWord size;
StgWord bitmap[FLEXIBLE_ARRAY];
/* An SRT is just an array of closure pointers: */
typedef StgClosure* StgSRT[];
-/* Each info table refers to some subset of the closure pointers in an
- SRT. It does this using a pair of an StgSRT pointer and a
- half-word bitmap. If the half-word bitmap isn't large enough, then
- we fall back to a large SRT, including an unbounded bitmap. If the
- half-word bitmap is set to all ones (0xffff), then the StgSRT
- pointer instead points to an StgLargeSRT: */
+/*
+ * Each info table refers to some subset of the closure pointers in an
+ * SRT. It does this using a pair of an StgSRT pointer and a
+ * half-word bitmap. If the half-word bitmap isn't large enough, then
+ * we fall back to a large SRT, including an unbounded bitmap. If the
+ * half-word bitmap is set to all ones (0xffff), then the StgSRT
+ * pointer instead points to an StgLargeSRT:
+ */
typedef struct StgLargeSRT_ {
StgSRT *srt;
StgLargeBitmap l;
} StgLargeSRT;
/* ----------------------------------------------------------------------------
+ Relative pointers
+
+ Several pointer fields in info tables are expressed as offsets
+ relative to the info pointer, so that we can generate
+ position-independent code.
+
+ There is a complication on the x86_64 platform, where pointeres are
+ 64 bits, but the tools don't support 64-bit relative relocations.
+ However, the default memory model (small) ensures that all symbols
+ have values in the lower 2Gb of the address space, so offsets all
+ fit in 32 bits. Hence we can use 32-bit offset fields.
+ ------------------------------------------------------------------------- */
+
+#if x86_64_TARGET_ARCH
+#define OFFSET_FIELD(n) StgHalfInt n; StgHalfWord __pad_##n;
+#else
+#define OFFSET_FIELD(n) StgInt n;
+#endif
+
+/* ----------------------------------------------------------------------------
Info Tables
------------------------------------------------------------------------- */
/*
- Stuff describing the closure layout. Well, actually, it might
- contain the selector index for a THUNK_SELECTOR. This union is one
- word long.
-*/
+ * Stuff describing the closure layout. Well, actually, it might
+ * contain the selector index for a THUNK_SELECTOR. This union is one
+ * word long.
+ */
typedef union {
struct { /* Heap closure payload layout: */
StgHalfWord ptrs; /* number of pointers */
StgWord bitmap; /* word-sized bit pattern describing */
/* a stack frame: see below */
+#ifndef TABLES_NEXT_TO_CODE
StgLargeBitmap* large_bitmap; /* pointer to large bitmap structure */
+#else
+ OFFSET_FIELD( large_bitmap_offset ); /* offset from info table to large bitmap structure */
+#endif
StgWord selector_offset; /* used in THUNK_SELECTORs */
/*
- The "standard" part of an info table. Every info table has this bit.
-*/
+ * The "standard" part of an info table. Every info table has this bit.
+ */
typedef struct _StgInfoTable {
#ifndef TABLES_NEXT_TO_CODE
- StgFunPtr entry; // pointer to the entry code
+ StgFunPtr entry; /* pointer to the entry code */
#endif
#if defined(PAR) || defined(GRAN)
StgProfInfo prof;
#endif
#ifdef TICKY
- MAYBE_EMPTY_STRUCT(StgTickyInfo,ticky)
+ /* Ticky-specific stuff would go here. */
#endif
#ifdef DEBUG_CLOSURE
- MAYBE_EMPTY_STRUCT(StgDebugInfo,debug)
+ /* Debug-specific stuff would go here. */
#endif
StgClosureInfo layout; /* closure layout info (one word) */
bitmap fields have also been omitted.
-------------------------------------------------------------------------- */
-typedef struct _StgFunInfoTable {
-#if defined(TABLES_NEXT_TO_CODE)
- StgFun *slow_apply; /* apply to args on the stack */
- StgWord bitmap; /* arg ptr/nonptr bitmap */
- StgSRT *srt; /* pointer to the SRT table */
+typedef struct _StgFunInfoExtraRev {
+ OFFSET_FIELD ( slow_apply_offset ); /* apply to args on the stack */
+ union {
+ StgWord bitmap;
+ OFFSET_FIELD ( bitmap_offset ); /* arg ptr/nonptr bitmap */
+ } b;
+ OFFSET_FIELD ( srt_offset ); /* pointer to the SRT table */
StgHalfWord fun_type; /* function type */
StgHalfWord arity; /* function arity */
- StgInfoTable i;
-#else
- StgInfoTable i;
+} StgFunInfoExtraRev;
+
+typedef struct _StgFunInfoExtraFwd {
StgHalfWord fun_type; /* function type */
StgHalfWord arity; /* function arity */
StgSRT *srt; /* pointer to the SRT table */
- StgWord bitmap; /* arg ptr/nonptr bitmap */
+ union { /* union for compat. with TABLES_NEXT_TO_CODE version */
+ StgWord bitmap; /* arg ptr/nonptr bitmap */
+ } b;
StgFun *slow_apply; /* apply to args on the stack */
+} StgFunInfoExtraFwd;
+
+typedef struct {
+#if defined(TABLES_NEXT_TO_CODE)
+ StgFunInfoExtraRev f;
+ StgInfoTable i;
+#else
+ StgInfoTable i;
+ StgFunInfoExtraFwd f;
#endif
} StgFunInfoTable;
Return info tables
-------------------------------------------------------------------------- */
-/* When info tables are laid out backwards, we can omit the SRT
- pointer iff srt_bitmap is zero. */
+/*
+ * When info tables are laid out backwards, we can omit the SRT
+ * pointer iff srt_bitmap is zero.
+ */
-typedef struct _StgRetInfoTable {
-#if !defined(TABLES_NEXT_TO_CODE)
- StgInfoTable i;
-#endif
- StgSRT *srt; /* pointer to the SRT table */
+typedef struct {
#if defined(TABLES_NEXT_TO_CODE)
+ OFFSET_FIELD( srt_offset ); /* offset to the SRT table */
StgInfoTable i;
-#endif
-#if !defined(TABLES_NEXT_TO_CODE)
+#else
+ StgInfoTable i;
+ StgSRT *srt; /* pointer to the SRT table */
StgFunPtr vector[FLEXIBLE_ARRAY];
#endif
} StgRetInfoTable;
Thunk info tables
-------------------------------------------------------------------------- */
-/* When info tables are laid out backwards, we can omit the SRT
- pointer iff srt_bitmap is zero. */
+/*
+ * When info tables are laid out backwards, we can omit the SRT
+ * pointer iff srt_bitmap is zero.
+ */
typedef struct _StgThunkInfoTable {
#if !defined(TABLES_NEXT_TO_CODE)
StgInfoTable i;
#endif
+#if defined(TABLES_NEXT_TO_CODE)
+ OFFSET_FIELD( srt_offset ); /* offset to the SRT table */
+#else
StgSRT *srt; /* pointer to the SRT table */
+#endif
#if defined(TABLES_NEXT_TO_CODE)
StgInfoTable i;
#endif
} StgThunkInfoTable;
+
+/* -----------------------------------------------------------------------------
+ Accessor macros for fields that might be offsets (C version)
+ -------------------------------------------------------------------------- */
+
+/*
+ * GET_SRT(info)
+ * info must be a Stg[Ret|Thunk]InfoTable* (an info table that has a SRT)
+ */
+#ifdef TABLES_NEXT_TO_CODE
+#define GET_SRT(info) ((StgSRT*) (((StgWord) ((info)+1)) + (info)->srt_offset))
+#else
+#define GET_SRT(info) ((info)->srt)
+#endif
+
+/*
+ * GET_FUN_SRT(info)
+ * info must be a StgFunInfoTable*
+ */
+#ifdef TABLES_NEXT_TO_CODE
+#define GET_FUN_SRT(info) ((StgSRT*) (((StgWord) ((info)+1)) + (info)->f.srt_offset))
+#else
+#define GET_FUN_SRT(info) ((info)->f.srt)
+#endif
+
+#ifdef TABLES_NEXT_TO_CODE
+#define GET_LARGE_BITMAP(info) ((StgLargeBitmap*) (((StgWord) ((info)+1)) \
+ + (info)->layout.large_bitmap_offset))
+#else
+#define GET_LARGE_BITMAP(info) ((info)->layout.large_bitmap)
+#endif
+
+#ifdef TABLES_NEXT_TO_CODE
+#define GET_FUN_LARGE_BITMAP(info) ((StgLargeBitmap*) (((StgWord) ((info)+1)) \
+ + (info)->f.b.bitmap_offset))
+#else
+#define GET_FUN_LARGE_BITMAP(info) ((StgLargeBitmap*) ((info)->f.b.bitmap))
+#endif
+
+
#endif /* INFOTABLES_H */