/* -----------------------------------------------------------------------------
- * $Id: Regs.h,v 1.14 2003/11/14 14:28:08 stolz Exp $
*
- * (c) The GHC Team, 1998-1999
+ * (c) The GHC Team, 1998-2004
*
- * Registers used in STG code. Might or might not correspond to
- * actual machine registers.
+ * Registers in the STG machine.
+ *
+ * The STG machine has a collection of "registers", each one of which
+ * may or may not correspond to an actual machine register when
+ * running code.
+ *
+ * The register set is backed by a table in memory (struct
+ * StgRegTable). If a particular STG register is not mapped to a
+ * machine register, then the apprpriate slot in this table is used
+ * instead.
+ *
+ * This table is itself pointed to by another register, BaseReg. If
+ * BaseReg is not in a machine register, then the register table is
+ * used from an absolute location (MainCapability).
*
* ---------------------------------------------------------------------------*/
#ifndef REGS_H
#define REGS_H
-/*
- * This file should do the right thing if we have no machine-registers
- * defined, i.e. everything lives in the RegTable.
- */
+#include "gmp.h" // Needs MP_INT definition
-/*
- * This is the table that holds shadow-locations for all the STG
- * registers. The shadow locations are used when:
- *
- * 1) the particular register isn't mapped to a real machine
- * register, probably because there's a shortage of real registers.
- * 2) caller-saves registers are saved across a CCall
+/*
+ * Spark pools: used to store pending sparks
+ * (THREADED_RTS & PARALLEL_HASKELL only)
+ * This is a circular buffer. Invariants:
+ * - base <= hd < lim
+ * - base <= tl < lim
+ * - if hd==tl, then the pool is empty.
+ * - if hd == tl+1, then the pool is full.
+ * Adding to the pool is done by assigning to *tl++ (wrapping round as
+ * necessary). When adding to a full pool, we have the option of
+ * throwing away either the oldest (hd++) or the most recent (tl--) entry.
*/
-
typedef struct StgSparkPool_ {
StgClosure **base;
StgClosure **lim;
StgClosure **tl;
} StgSparkPool;
+#define ASSERT_SPARK_POOL_INVARIANTS(p) \
+ ASSERT((p)->base <= (p)->hd); \
+ ASSERT((p)->hd < (p)->lim); \
+ ASSERT((p)->base <= (p)->tl); \
+ ASSERT((p)->tl < (p)->lim);
+
typedef struct {
StgFunPtr stgGCEnter1;
StgFunPtr stgGCFun;
} StgFunTable;
+/*
+ * Vanilla registers are given this union type, which is purely so
+ * that we can cast the vanilla reg to a variety of types with the
+ * minimum of syntax. eg. R1.w instead of (StgWord)R1.
+ */
+typedef union {
+ StgWord w;
+ StgAddr a;
+ StgChar c;
+ StgInt8 i8;
+ StgFloat f;
+ StgInt i;
+ StgPtr p;
+ StgClosurePtr cl;
+ StgStackOffset offset; /* unused? */
+ StgByteArray b;
+ StgTSOPtr t;
+} StgUnion;
+
+/*
+ * This is the table that holds shadow-locations for all the STG
+ * registers. The shadow locations are used when:
+ *
+ * 1) the particular register isn't mapped to a real machine
+ * register, probably because there's a shortage of real registers.
+ * 2) caller-saves registers are saved across a CCall
+ */
typedef struct StgRegTable_ {
StgUnion rR1;
StgUnion rR2;
StgUnion rR6;
StgUnion rR7;
StgUnion rR8;
- StgUnion rR9; // used occasionally by heap/stack checks
- StgUnion rR10; // used occasionally by heap/stack checks
+ StgUnion rR9; /* used occasionally by heap/stack checks */
+ StgUnion rR10; /* used occasionally by heap/stack checks */
StgFloat rF1;
StgFloat rF2;
StgFloat rF3;
StgPtr rSpLim;
StgPtr rHp;
StgPtr rHpLim;
- StgTSO *rCurrentTSO;
- struct _bdescr *rNursery;
- struct _bdescr *rCurrentNursery;
- StgWord rHpAlloc; // number of words being allocated in heap
-#if defined(SMP) || defined(PAR)
- StgSparkPool rSparks; // per-task spark pool
+ struct StgTSO_ *rCurrentTSO;
+ struct step_ *rNursery;
+ struct bdescr_ *rCurrentNursery; /* Hp/HpLim point into this block */
+ struct bdescr_ *rCurrentAlloc; /* for allocation using allocate() */
+ StgWord rHpAlloc; /* number of *bytes* being allocated in heap */
+ // rmp_tmp1..rmp_result2 are only used in THREADED_RTS builds to
+ // avoid per-thread temps in bss, but currently always incldue here
+ // so we just run mkDerivedConstants once
+ StgInt rmp_tmp_w;
+ MP_INT rmp_tmp1;
+ MP_INT rmp_tmp2;
+ MP_INT rmp_result1;
+ MP_INT rmp_result2;
+ StgWord rRet; // holds the return code of the thread
+#if defined(THREADED_RTS) || defined(PAR)
+ StgSparkPool rSparks; /* per-task spark pool */
#endif
} StgRegTable;
-
-/* A capability is a combination of a FunTable and a RegTable. In STG
- * code, BaseReg normally points to the RegTable portion of this
- * structure, so that we can index both forwards and backwards to take
- * advantage of shorter instruction forms on some archs (eg. x86).
- */
-typedef struct Capability_ {
- StgFunTable f;
- StgRegTable r;
-#if defined(SMP)
- struct Capability_ *link; /* per-task register tables are linked together */
-#endif
-} Capability;
-
-/* No such thing as a MainRegTable under SMP - each thread must
- * have its own MainRegTable.
- */
-#ifndef SMP
-extern DLL_IMPORT_RTS Capability MainCapability;
-#endif
-
#if IN_STG_CODE
/*
#define SAVE_CurrentTSO (BaseReg->rCurrentTSO)
#define SAVE_CurrentNursery (BaseReg->rCurrentNursery)
#define SAVE_HpAlloc (BaseReg->rHpAlloc)
-#if defined(SMP) || defined(PAR)
#define SAVE_SparkHd (BaseReg->rSparks.hd)
#define SAVE_SparkTl (BaseReg->rSparks.tl)
#define SAVE_SparkBase (BaseReg->rSparks.base)
#define SAVE_SparkLim (BaseReg->rSparks.lim)
-#endif
/* We sometimes need to save registers across a C-call, eg. if they
* are clobbered in the standard calling convention. We define the
* again for no good reason (on register-poor architectures).
*/
+/* define NO_REGS to omit register declarations - used in RTS C code
+ * that needs all the STG definitions but not the global register
+ * settings.
+ */
#define GLOBAL_REG_DECL(type,name,reg) register type name REG(reg);
-#ifdef REG_R1
+#if defined(REG_R1) && !defined(NO_GLOBAL_REG_DECLS)
GLOBAL_REG_DECL(StgUnion,R1,REG_R1)
#else
-#define R1 (BaseReg->rR1)
+# define R1 (BaseReg->rR1)
#endif
-#ifdef REG_R2
+#if defined(REG_R2) && !defined(NO_GLOBAL_REG_DECLS)
GLOBAL_REG_DECL(StgUnion,R2,REG_R2)
#else
-#define R2 (BaseReg->rR2)
+# define R2 (BaseReg->rR2)
#endif
-#ifdef REG_R3
+#if defined(REG_R3) && !defined(NO_GLOBAL_REG_DECLS)
GLOBAL_REG_DECL(StgUnion,R3,REG_R3)
#else
# define R3 (BaseReg->rR3)
#endif
-#ifdef REG_R4
+#if defined(REG_R4) && !defined(NO_GLOBAL_REG_DECLS)
GLOBAL_REG_DECL(StgUnion,R4,REG_R4)
#else
# define R4 (BaseReg->rR4)
#endif
-#ifdef REG_R5
+#if defined(REG_R5) && !defined(NO_GLOBAL_REG_DECLS)
GLOBAL_REG_DECL(StgUnion,R5,REG_R5)
#else
# define R5 (BaseReg->rR5)
#endif
-#ifdef REG_R6
+#if defined(REG_R6) && !defined(NO_GLOBAL_REG_DECLS)
GLOBAL_REG_DECL(StgUnion,R6,REG_R6)
#else
# define R6 (BaseReg->rR6)
#endif
-#ifdef REG_R7
+#if defined(REG_R7) && !defined(NO_GLOBAL_REG_DECLS)
GLOBAL_REG_DECL(StgUnion,R7,REG_R7)
#else
# define R7 (BaseReg->rR7)
#endif
-#ifdef REG_R8
+#if defined(REG_R8) && !defined(NO_GLOBAL_REG_DECLS)
GLOBAL_REG_DECL(StgUnion,R8,REG_R8)
#else
# define R8 (BaseReg->rR8)
#endif
-#ifdef REG_R9
+#if defined(REG_R9) && !defined(NO_GLOBAL_REG_DECLS)
GLOBAL_REG_DECL(StgUnion,R9,REG_R9)
#else
# define R9 (BaseReg->rR9)
#endif
-#ifdef REG_R10
+#if defined(REG_R10) && !defined(NO_GLOBAL_REG_DECLS)
GLOBAL_REG_DECL(StgUnion,R10,REG_R10)
#else
# define R10 (BaseReg->rR10)
#endif
-#ifdef REG_F1
+#if defined(REG_F1) && !defined(NO_GLOBAL_REG_DECLS)
GLOBAL_REG_DECL(StgFloat,F1,REG_F1)
#else
#define F1 (BaseReg->rF1)
#endif
-#ifdef REG_F2
+#if defined(REG_F2) && !defined(NO_GLOBAL_REG_DECLS)
GLOBAL_REG_DECL(StgFloat,F2,REG_F2)
#else
#define F2 (BaseReg->rF2)
#endif
-#ifdef REG_F3
+#if defined(REG_F3) && !defined(NO_GLOBAL_REG_DECLS)
GLOBAL_REG_DECL(StgFloat,F3,REG_F3)
#else
#define F3 (BaseReg->rF3)
#endif
-#ifdef REG_F4
+#if defined(REG_F4) && !defined(NO_GLOBAL_REG_DECLS)
GLOBAL_REG_DECL(StgFloat,F4,REG_F4)
#else
#define F4 (BaseReg->rF4)
#endif
-#ifdef REG_D1
+#if defined(REG_D1) && !defined(NO_GLOBAL_REG_DECLS)
GLOBAL_REG_DECL(StgDouble,D1,REG_D1)
#else
#define D1 (BaseReg->rD1)
#endif
-#ifdef REG_D2
+#if defined(REG_D2) && !defined(NO_GLOBAL_REG_DECLS)
GLOBAL_REG_DECL(StgDouble,D2,REG_D2)
#else
#define D2 (BaseReg->rD2)
#endif
-#ifdef REG_L1
+#if defined(REG_L1) && !defined(NO_GLOBAL_REG_DECLS)
GLOBAL_REG_DECL(StgWord64,L1,REG_L1)
#else
#define L1 (BaseReg->rL1)
* concurrent Haskell, MainRegTable otherwise).
*/
-#ifdef REG_Base
+/* A capability is a combination of a FunTable and a RegTable. In STG
+ * code, BaseReg normally points to the RegTable portion of this
+ * structure, so that we can index both forwards and backwards to take
+ * advantage of shorter instruction forms on some archs (eg. x86).
+ * This is a cut-down version of the Capability structure; the full
+ * version is defined in Capability.h.
+ */
+struct PartCapability_ {
+ StgFunTable f;
+ StgRegTable r;
+};
+
+/* No such thing as a MainCapability under THREADED_RTS - each thread must have
+ * its own Capability.
+ */
+#if IN_STG_CODE && !defined(THREADED_RTS)
+extern W_ MainCapability[];
+#endif
+
+/*
+ * Assigning to BaseReg (the ASSIGN_BaseReg macro): this happens on
+ * return from a "safe" foreign call, when the thread might be running
+ * on a new Capability. Obviously if BaseReg is not a register, then
+ * we are restricted to a single Capability (this invariant is enforced
+ * in Capability.c:initCapabilities), and assigning to BaseReg can be omitted.
+ */
+
+#if defined(REG_Base) && !defined(NO_GLOBAL_REG_DECLS)
GLOBAL_REG_DECL(StgRegTable *,BaseReg,REG_Base)
+#define ASSIGN_BaseReg(e) (BaseReg = (e))
#else
-#ifdef SMP
-#error BaseReg must be in a register for SMP
+#ifdef THREADED_RTS
+#error BaseReg must be in a register for THREADED_RTS
#endif
-#define BaseReg (&MainCapability.r)
+#define BaseReg (&((struct PartCapability_ *)MainCapability)->r)
+#define ASSIGN_BaseReg(e) (e)
#endif
-#ifdef REG_Sp
+#if defined(REG_Sp) && !defined(NO_GLOBAL_REG_DECLS)
GLOBAL_REG_DECL(P_,Sp,REG_Sp)
#else
#define Sp (BaseReg->rSp)
#endif
-#ifdef REG_SpLim
+#if defined(REG_SpLim) && !defined(NO_GLOBAL_REG_DECLS)
GLOBAL_REG_DECL(P_,SpLim,REG_SpLim)
#else
#define SpLim (BaseReg->rSpLim)
#endif
-#ifdef REG_Hp
+#if defined(REG_Hp) && !defined(NO_GLOBAL_REG_DECLS)
GLOBAL_REG_DECL(P_,Hp,REG_Hp)
#else
#define Hp (BaseReg->rHp)
#endif
-#ifdef REG_HpLim
+#if defined(REG_HpLim) && !defined(NO_GLOBAL_REG_DECLS)
GLOBAL_REG_DECL(P_,HpLim,REG_HpLim)
#else
#define HpLim (BaseReg->rHpLim)
#endif
-#ifdef REG_CurrentTSO
-GLOBAL_REG_DECL(StgTSO *,CurrentTSO,REG_CurrentTSO)
+#if defined(REG_CurrentTSO) && !defined(NO_GLOBAL_REG_DECLS)
+GLOBAL_REG_DECL(struct _StgTSO *,CurrentTSO,REG_CurrentTSO)
#else
#define CurrentTSO (BaseReg->rCurrentTSO)
#endif
-#ifdef REG_CurrentNursery
+#if defined(REG_CurrentNursery) && !defined(NO_GLOBAL_REG_DECLS)
GLOBAL_REG_DECL(bdescr *,CurrentNursery,REG_CurrentNursery)
#else
#define CurrentNursery (BaseReg->rCurrentNursery)
#endif
-#ifdef REG_HpAlloc
+#if defined(REG_HpAlloc) && !defined(NO_GLOBAL_REG_DECLS)
GLOBAL_REG_DECL(bdescr *,HpAlloc,REG_HpAlloc)
#else
#define HpAlloc (BaseReg->rHpAlloc)
#endif
-#ifdef REG_SparkHd
+#if defined(REG_SparkHd) && !defined(NO_GLOBAL_REG_DECLS)
GLOBAL_REG_DECL(bdescr *,SparkHd,REG_SparkHd)
#else
#define SparkHd (BaseReg->rSparks.hd)
#endif
-#ifdef REG_SparkTl
+#if defined(REG_SparkTl) && !defined(NO_GLOBAL_REG_DECLS)
GLOBAL_REG_DECL(bdescr *,SparkTl,REG_SparkTl)
#else
#define SparkTl (BaseReg->rSparks.tl)
#endif
-#ifdef REG_SparkBase
+#if defined(REG_SparkBase) && !defined(NO_GLOBAL_REG_DECLS)
GLOBAL_REG_DECL(bdescr *,SparkBase,REG_SparkBase)
#else
#define SparkBase (BaseReg->rSparks.base)
#endif
-#ifdef REG_SparkLim
+#if defined(REG_SparkLim) && !defined(NO_GLOBAL_REG_DECLS)
GLOBAL_REG_DECL(bdescr *,SparkLim,REG_SparkLim)
#else
#define SparkLim (BaseReg->rSparks.lim)
#endif
#ifdef CALLER_SAVES_Base
-#ifdef SMP
-#error "Can't have caller-saved BaseReg with SMP"
+#ifdef THREADED_RTS
+#error "Can't have caller-saved BaseReg with THREADED_RTS"
#endif
#define CALLER_SAVE_Base /* nothing */
#define CALLER_RESTORE_Base BaseReg = &MainRegTable;
#define CALLER_RESTORE_SYSTEM /* nothing */
#endif /* IN_STG_CODE */
-
#define CALLER_SAVE_ALL \
CALLER_SAVE_SYSTEM \
CALLER_SAVE_USER
CALLER_RESTORE_USER
#endif /* REGS_H */
-