Implement unboxed sum primitive type
[ghc.git] / rts / StgMiscClosures.cmm
index 58cbaf9..70d219a 100644 (file)
 
 #include "Cmm.h"
 
+import pthread_mutex_lock;
+import ghczmprim_GHCziTypes_Czh_static_info;
+import ghczmprim_GHCziTypes_Izh_static_info;
+import EnterCriticalSection;
+import LeaveCriticalSection;
+
+/* ----------------------------------------------------------------------------
+   Stack underflow
+   ------------------------------------------------------------------------- */
+
+INFO_TABLE_RET (stg_stack_underflow_frame, UNDERFLOW_FRAME,
+                W_ info_ptr, P_ unused)
+    /* no args => explicit stack */
+{
+    W_ new_tso;
+    W_ ret_off;
+
+    SAVE_STGREGS
+
+    SAVE_THREAD_STATE();
+    (ret_off) = foreign "C" threadStackUnderflow(MyCapability() "ptr",
+                                                 CurrentTSO);
+    LOAD_THREAD_STATE();
+
+    RESTORE_STGREGS
+
+    jump %ENTRY_CODE(Sp(ret_off)) [*]; // NB. all registers live!
+}
+
+/* ----------------------------------------------------------------------------
+   Restore a saved cost centre
+   ------------------------------------------------------------------------- */
+
+INFO_TABLE_RET (stg_restore_cccs, RET_SMALL, W_ info_ptr, W_ cccs)
+{
+    unwind Sp = Sp + WDS(2);
+#if defined(PROFILING)
+    CCCS = Sp(1);
+#endif
+    Sp_adj(2);
+    jump %ENTRY_CODE(Sp(0)) [*]; // NB. all registers live!
+}
+
 /* ----------------------------------------------------------------------------
    Support for the bytecode interpreter.
    ------------------------------------------------------------------------- */
 
 /* 9 bits of return code for constructors created by the interpreter. */
-stg_interp_constr_entry
-{ 
-    /* R1 points at the constructor */
-    jump %ENTRY_CODE(Sp(0));
+stg_interp_constr_entry (P_ ret)
+{
+    return (ret);
 }
 
 /* Some info tables to be used when compiled code returns a value to
@@ -34,7 +76,7 @@ stg_interp_constr_entry
 
       ptr to BCO holding return continuation
       ptr to one of these info tables.
+
    The info table code, both direct and vectored, must:
       * push R1/F1/D1 on the stack, and its tag if necessary
       * push the BCO (so it's now on the stack twice)
@@ -58,76 +100,83 @@ stg_interp_constr_entry
 */
 
 INFO_TABLE_RET( stg_ctoi_R1p, RET_BCO)
+    /* explicit stack */
 {
     Sp_adj(-2);
     Sp(1) = R1;
     Sp(0) = stg_enter_info;
-    jump stg_yield_to_interpreter;
+    jump stg_yield_to_interpreter [];
 }
 
 /*
- * When the returned value is a pointer, but unlifted, in R1 ... 
+ * When the returned value is a pointer, but unlifted, in R1 ...
  */
 INFO_TABLE_RET( stg_ctoi_R1unpt, RET_BCO )
+    /* explicit stack */
 {
     Sp_adj(-2);
     Sp(1) = R1;
-    Sp(0) = stg_gc_unpt_r1_info;
-    jump stg_yield_to_interpreter;
+    Sp(0) = stg_ret_p_info;
+    jump stg_yield_to_interpreter [];
 }
 
 /*
  * When the returned value is a non-pointer in R1 ...
  */
 INFO_TABLE_RET( stg_ctoi_R1n, RET_BCO )
+    /* explicit stack */
 {
     Sp_adj(-2);
     Sp(1) = R1;
-    Sp(0) = stg_gc_unbx_r1_info;
-    jump stg_yield_to_interpreter;
+    Sp(0) = stg_ret_n_info;
+    jump stg_yield_to_interpreter [];
 }
 
 /*
  * When the returned value is in F1
  */
 INFO_TABLE_RET( stg_ctoi_F1, RET_BCO )
+    /* explicit stack */
 {
     Sp_adj(-2);
     F_[Sp + WDS(1)] = F1;
-    Sp(0) = stg_gc_f1_info;
-    jump stg_yield_to_interpreter;
+    Sp(0) = stg_ret_f_info;
+    jump stg_yield_to_interpreter [];
 }
 
 /*
  * When the returned value is in D1
  */
 INFO_TABLE_RET( stg_ctoi_D1, RET_BCO )
+    /* explicit stack */
 {
     Sp_adj(-1) - SIZEOF_DOUBLE;
     D_[Sp + WDS(1)] = D1;
-    Sp(0) = stg_gc_d1_info;
-    jump stg_yield_to_interpreter;
+    Sp(0) = stg_ret_d_info;
+    jump stg_yield_to_interpreter [];
 }
 
 /*
  * When the returned value is in L1
  */
 INFO_TABLE_RET( stg_ctoi_L1, RET_BCO )
+    /* explicit stack */
 {
     Sp_adj(-1) - 8;
     L_[Sp + WDS(1)] = L1;
-    Sp(0) = stg_gc_l1_info;
-    jump stg_yield_to_interpreter;
+    Sp(0) = stg_ret_l_info;
+    jump stg_yield_to_interpreter [];
 }
 
 /*
  * When the returned value is a void
  */
 INFO_TABLE_RET( stg_ctoi_V, RET_BCO )
+    /* explicit stack */
 {
     Sp_adj(-1);
-    Sp(0) = stg_gc_void_info;
-    jump stg_yield_to_interpreter;
+    Sp(0) = stg_ret_v_info;
+    jump stg_yield_to_interpreter [];
 }
 
 /*
@@ -136,9 +185,10 @@ INFO_TABLE_RET( stg_ctoi_V, RET_BCO )
  * stack.
  */
 INFO_TABLE_RET( stg_apply_interp, RET_BCO )
+    /* explicit stack */
 {
     /* Just in case we end up in here... (we shouldn't) */
-    jump stg_yield_to_interpreter;
+    jump stg_yield_to_interpreter [];
 }
 
 /* ----------------------------------------------------------------------------
@@ -146,12 +196,15 @@ INFO_TABLE_RET( stg_apply_interp, RET_BCO )
    ------------------------------------------------------------------------- */
 
 INFO_TABLE_FUN( stg_BCO, 4, 0, BCO, "BCO", "BCO", ARG_BCO )
+    /* explicit stack */
 {
   /* entering a BCO means "apply it", same as a function */
   Sp_adj(-2);
+  // Skip the stack check; the interpreter will do one before using
+  // the stack anyway.
   Sp(1) = R1;
   Sp(0) = stg_apply_interp_info;
-  jump stg_yield_to_interpreter;
+  jump stg_yield_to_interpreter [];
 }
 
 /* ----------------------------------------------------------------------------
@@ -165,107 +218,44 @@ INFO_TABLE_FUN( stg_BCO, 4, 0, BCO, "BCO", "BCO", ARG_BCO )
    ------------------------------------------------------------------------- */
 
 INFO_TABLE(stg_IND,1,0,IND,"IND","IND")
+#if 0
+/*
+  This version in high-level cmm generates slightly less good code
+  than the low-level version below it. (ToDo)
+*/
+    (P_ node)
 {
-    TICK_ENT_DYN_IND();        /* tick */
-    R1 = UNTAG(StgInd_indirectee(R1));
-    TICK_ENT_VIA_NODE();
-    jump %GET_ENTRY(R1);
-}
-
-INFO_TABLE(stg_IND_direct,1,0,IND,"IND","IND")
-{
-    TICK_ENT_DYN_IND();        /* tick */
-    R1 = StgInd_indirectee(R1);
+    TICK_ENT_DYN_IND(); /* tick */
+    node = UNTAG(StgInd_indirectee(node));
     TICK_ENT_VIA_NODE();
-    jump %ENTRY_CODE(Sp(0));
+    jump %GET_ENTRY(node) (node);
 }
-
-INFO_TABLE(stg_IND_STATIC,1,0,IND_STATIC,"IND_STATIC","IND_STATIC")
+#else
+    /* explicit stack */
 {
-    TICK_ENT_STATIC_IND();     /* tick */
+    TICK_ENT_DYN_IND(); /* tick */
     R1 = UNTAG(StgInd_indirectee(R1));
     TICK_ENT_VIA_NODE();
-    jump %GET_ENTRY(R1);
+    jump %GET_ENTRY(R1) [R1];
 }
-
-INFO_TABLE(stg_IND_PERM,1,0,IND_PERM,"IND_PERM","IND_PERM")
-{
-    /* Don't add INDs to granularity cost */
-
-    /* Don't: TICK_ENT_STATIC_IND(Node); for ticky-ticky; this ind is
-       here only to help profiling */
-
-#if defined(TICKY_TICKY) && !defined(PROFILING)
-    /* TICKY_TICKY && !PROFILING means PERM_IND *replaces* an IND, rather than
-       being extra  */
-    TICK_ENT_PERM_IND();
-#endif
-
-    LDV_ENTER(R1);
-
-    /* Enter PAP cost centre */
-    ENTER_CCS_PAP_CL(R1);
-
-    /* For ticky-ticky, change the perm_ind to a normal ind on first
-     * entry, so the number of ent_perm_inds is the number of *thunks*
-     * entered again, not the number of subsequent entries.
-     *
-     * Since this screws up cost centres, we die if profiling and
-     * ticky_ticky are on at the same time.  KSW 1999-01.
-     */
-#ifdef TICKY_TICKY
-#  ifdef PROFILING
-#    error Profiling and ticky-ticky do not mix at present!
-#  endif  /* PROFILING */
-    StgHeader_info(R1) = stg_IND_info;
-#endif /* TICKY_TICKY */
-
-    R1 = UNTAG(StgInd_indirectee(R1));
-
-#if defined(TICKY_TICKY) && !defined(PROFILING)
-    TICK_ENT_VIA_NODE();
 #endif
 
-    jump %GET_ENTRY(R1);
-}  
-
-
-INFO_TABLE(stg_IND_OLDGEN,1,0,IND_OLDGEN,"IND_OLDGEN","IND_OLDGEN")
+INFO_TABLE(stg_IND_direct,1,0,IND,"IND","IND")
+    (P_ node)
 {
-    TICK_ENT_STATIC_IND();     /* tick */
-    R1 = UNTAG(StgInd_indirectee(R1));
+    TICK_ENT_DYN_IND(); /* tick */
+    node = StgInd_indirectee(node);
     TICK_ENT_VIA_NODE();
-    jump %GET_ENTRY(R1);
+    jump %ENTRY_CODE(Sp(0)) (node);
 }
 
-INFO_TABLE(stg_IND_OLDGEN_PERM,1,0,IND_OLDGEN_PERM,"IND_OLDGEN_PERM","IND_OLDGEN_PERM")
+INFO_TABLE(stg_IND_STATIC,1,0,IND_STATIC,"IND_STATIC","IND_STATIC")
+    /* explicit stack */
 {
-    /* Don't: TICK_ENT_STATIC_IND(Node); for ticky-ticky; 
-       this ind is here only to help profiling */
-
-#if defined(TICKY_TICKY) && !defined(PROFILING)
-    /* TICKY_TICKY && !PROFILING means PERM_IND *replaces* an IND, 
-       rather than being extra  */
-    TICK_ENT_PERM_IND(); /* tick */
-#endif
-
-    LDV_ENTER(R1);
-
-    /* Enter PAP cost centre -- lexical scoping only */
-    ENTER_CCS_PAP_CL(R1);
-
-    /* see comment in IND_PERM */
-#ifdef TICKY_TICKY
-#  ifdef PROFILING
-#    error Profiling and ticky-ticky do not mix at present!
-#  endif  /* PROFILING */
-    StgHeader_info(R1) = stg_IND_OLDGEN_info;
-#endif /* TICKY_TICKY */
-
+    TICK_ENT_STATIC_IND(); /* tick */
     R1 = UNTAG(StgInd_indirectee(R1));
-
     TICK_ENT_VIA_NODE();
-    jump %GET_ENTRY(R1);
+    jump %GET_ENTRY(R1) [R1];
 }
 
 /* ----------------------------------------------------------------------------
@@ -277,124 +267,110 @@ INFO_TABLE(stg_IND_OLDGEN_PERM,1,0,IND_OLDGEN_PERM,"IND_OLDGEN_PERM","IND_OLDGEN
    waiting for the evaluation of the closure to finish.
    ------------------------------------------------------------------------- */
 
-/* Note: a BLACKHOLE must be big enough to be
- * overwritten with an indirection/evacuee/catch.  Thus we claim it
- * has 1 non-pointer word of payload. 
- */
-INFO_TABLE(stg_BLACKHOLE,0,1,BLACKHOLE,"BLACKHOLE","BLACKHOLE")
+INFO_TABLE(stg_BLACKHOLE,1,0,BLACKHOLE,"BLACKHOLE","BLACKHOLE")
+    (P_ node)
 {
-#if defined(GRAN)
-    /* Before overwriting TSO_LINK */
-    STGCALL3(GranSimBlock,CurrentTSO,CurrentProc,(StgClosure *)R1 /*Node*/);
-#endif
-
-    TICK_ENT_BH();
-
-#ifdef THREADED_RTS
-    // foreign "C" debugBelch("BLACKHOLE entry\n");
-#endif
-
-    /* Actually this is not necessary because R1 is about to be destroyed. */
-    LDV_ENTER(R1);
-
-#if defined(THREADED_RTS)
-    foreign "C" ACQUIRE_LOCK(sched_mutex "ptr");
-    // released in stg_block_blackhole_finally
-#endif
-
-    /* Put ourselves on the blackhole queue */
-    StgTSO_link(CurrentTSO) = W_[blackhole_queue];
-    W_[blackhole_queue] = CurrentTSO;
-
-    /* jot down why and on what closure we are blocked */
-    StgTSO_why_blocked(CurrentTSO) = BlockedOnBlackHole::I16;
-    StgTSO_block_info(CurrentTSO) = R1;
-
-    jump stg_block_blackhole;
+    W_ r, info, owner, bd;
+    P_ p, bq, msg;
+
+    TICK_ENT_DYN_IND(); /* tick */
+
+retry:
+    p = StgInd_indirectee(node);
+    if (GETTAG(p) != 0) {
+        return (p);
+    }
+
+    info = StgHeader_info(p);
+    if (info == stg_IND_info) {
+        // This could happen, if e.g. we got a BLOCKING_QUEUE that has
+        // just been replaced with an IND by another thread in
+        // wakeBlockingQueue().
+        goto retry;
+    }
+
+    if (info == stg_TSO_info ||
+        info == stg_BLOCKING_QUEUE_CLEAN_info ||
+        info == stg_BLOCKING_QUEUE_DIRTY_info)
+    {
+        ("ptr" msg) = ccall allocate(MyCapability() "ptr",
+                                     BYTES_TO_WDS(SIZEOF_MessageBlackHole));
+
+        SET_HDR(msg, stg_MSG_BLACKHOLE_info, CCS_SYSTEM);
+        MessageBlackHole_tso(msg) = CurrentTSO;
+        MessageBlackHole_bh(msg) = node;
+
+        (r) = ccall messageBlackHole(MyCapability() "ptr", msg "ptr");
+
+        if (r == 0) {
+            goto retry;
+        } else {
+            StgTSO_why_blocked(CurrentTSO) = BlockedOnBlackHole::I16;
+            StgTSO_block_info(CurrentTSO) = msg;
+            jump stg_block_blackhole(node);
+        }
+    }
+    else
+    {
+        ENTER(p);
+    }
 }
 
-#if defined(PAR) || defined(GRAN)
-
-INFO_TABLE(stg_RBH,1,1,RBH,"RBH","RBH")
+// CAF_BLACKHOLE is allocated when entering a CAF.  The reason it is
+// distinct from BLACKHOLE is so that we can tell the difference
+// between an update frame on the stack that points to a CAF under
+// evaluation, and one that points to a closure that is under
+// evaluation by another thread (a BLACKHOLE).  see Note [suspend
+// duplicate work] in ThreadPaused.c
+//
+INFO_TABLE(stg_CAF_BLACKHOLE,1,0,BLACKHOLE,"BLACKHOLE","BLACKHOLE")
+    (P_ node)
 {
-# if defined(GRAN)
-    /* mainly statistics gathering for GranSim simulation */
-    STGCALL3(GranSimBlock,CurrentTSO,CurrentProc,(StgClosure *)R1 /*Node*/);
-# endif
-
-    /* exactly the same as a BLACKHOLE_BQ_entry -- HWL */
-    /* Put ourselves on the blocking queue for this black hole */
-    TSO_link(CurrentTSO) = StgBlockingQueue_blocking_queue(R1);
-    StgBlockingQueue_blocking_queue(R1) = CurrentTSO;
-    /* jot down why and on what closure we are blocked */
-    TSO_why_blocked(CurrentTSO) = BlockedOnBlackHole::I16;
-    TSO_block_info(CurrentTSO) = R1;
-
-    /* PAR: dumping of event now done in blockThread -- HWL */
-
-    /* stg_gen_block is too heavyweight, use a specialised one */
-    jump stg_block_1;
+    jump ENTRY_LBL(stg_BLACKHOLE) (node);
 }
 
-INFO_TABLE(stg_RBH_Save_0,0,2,CONSTR,"RBH_Save_0","RBH_Save_0")
-{ foreign "C" barf("RBH_Save_0 object entered!"); }
-
-INFO_TABLE(stg_RBH_Save_1,1,1,CONSTR,"RBH_Save_1","RBH_Save_1");
-{ foreign "C" barf("RBH_Save_1 object entered!"); }
-
-INFO_TABLE(stg_RBH_Save_2,2,0,CONSTR,"RBH_Save_2","RBH_Save_2");
-{ foreign "C" barf("RBH_Save_2 object entered!"); }
-
-#endif /* defined(PAR) || defined(GRAN) */
-
-/* identical to BLACKHOLEs except for the infotag */
-INFO_TABLE(stg_CAF_BLACKHOLE,0,1,CAF_BLACKHOLE,"CAF_BLACKHOLE","CAF_BLACKHOLE")
+// EAGER_BLACKHOLE exists for the same reason as CAF_BLACKHOLE (see above).
+INFO_TABLE(__stg_EAGER_BLACKHOLE,1,0,BLACKHOLE,"BLACKHOLE","BLACKHOLE")
+    (P_ node)
 {
-#if defined(GRAN)
-    /* mainly statistics gathering for GranSim simulation */
-    STGCALL3(GranSimBlock,CurrentTSO,CurrentProc,(StgClosure *)R1 /*Node*/);
-#endif
-
-    TICK_ENT_BH();
-    LDV_ENTER(R1);
-
-#if defined(THREADED_RTS)
-    // foreign "C" debugBelch("BLACKHOLE entry\n");
-#endif
-
-#if defined(THREADED_RTS)
-    foreign "C" ACQUIRE_LOCK(sched_mutex "ptr");
-    // released in stg_block_blackhole_finally
-#endif
-
-    /* Put ourselves on the blackhole queue */
-    StgTSO_link(CurrentTSO) = W_[blackhole_queue];
-    W_[blackhole_queue] = CurrentTSO;
+    jump ENTRY_LBL(stg_BLACKHOLE) (node);
+}
 
-    /* jot down why and on what closure we are blocked */
-    StgTSO_why_blocked(CurrentTSO) = BlockedOnBlackHole::I16;
-    StgTSO_block_info(CurrentTSO) = R1;
+INFO_TABLE(stg_BLOCKING_QUEUE_CLEAN,4,0,BLOCKING_QUEUE,"BLOCKING_QUEUE","BLOCKING_QUEUE")
+{ foreign "C" barf("BLOCKING_QUEUE_CLEAN object entered!") never returns; }
 
-    jump stg_block_blackhole;
-}
 
-#ifdef EAGER_BLACKHOLING
-INFO_TABLE(stg_SE_BLACKHOLE,0,1,SE_BLACKHOLE,"SE_BLACKHOLE","SE_BLACKHOLE")
-{ foreign "C" barf("SE_BLACKHOLE object entered!"); }
+INFO_TABLE(stg_BLOCKING_QUEUE_DIRTY,4,0,BLOCKING_QUEUE,"BLOCKING_QUEUE","BLOCKING_QUEUE")
+{ foreign "C" barf("BLOCKING_QUEUE_DIRTY object entered!") never returns; }
 
-INFO_TABLE(stg_SE_CAF_BLACKHOLE,0,1,SE_CAF_BLACKHOLE,"SE_CAF_BLACKHOLE","SE_CAF_BLACKHOLE")
-{ foreign "C" barf("SE_CAF_BLACKHOLE object entered!"); }
-#endif
 
 /* ----------------------------------------------------------------------------
    Whiteholes are used for the "locked" state of a closure (see lockClosure())
-
-   The closure type is BLAKCHOLE, just because we need a valid closure type
-   for sanity checking.
    ------------------------------------------------------------------------- */
 
-INFO_TABLE(stg_WHITEHOLE, 0,0, BLACKHOLE, "WHITEHOLE", "WHITEHOLE")
-{ foreign "C" barf("WHITEHOLE object entered!"); }
+INFO_TABLE(stg_WHITEHOLE, 0,0, WHITEHOLE, "WHITEHOLE", "WHITEHOLE")
+    (P_ node)
+{
+#if defined(THREADED_RTS)
+    W_ info, i;
+
+    i = 0;
+loop:
+    // spin until the WHITEHOLE is updated
+    info = StgHeader_info(node);
+    if (info == stg_WHITEHOLE_info) {
+        i = i + 1;
+        if (i == SPIN_COUNT) {
+            i = 0;
+            ccall yieldThread();
+        }
+        goto loop;
+    }
+    jump %ENTRY_CODE(info) (node);
+#else
+    ccall barf("WHITEHOLE object entered!") never returns;
+#endif
+}
 
 /* ----------------------------------------------------------------------------
    Some static info tables for things that don't get entered, and
@@ -403,15 +379,13 @@ INFO_TABLE(stg_WHITEHOLE, 0,0, BLACKHOLE, "WHITEHOLE", "WHITEHOLE")
    ------------------------------------------------------------------------- */
 
 INFO_TABLE(stg_TSO, 0,0,TSO, "TSO", "TSO")
-{ foreign "C" barf("TSO object entered!"); }
+{ foreign "C" barf("TSO object entered!") never returns; }
 
-/* ----------------------------------------------------------------------------
-   Evacuees are left behind by the garbage collector.  Any attempt to enter
-   one is a real bug.
-   ------------------------------------------------------------------------- */
+INFO_TABLE(stg_STACK, 0,0, STACK, "STACK", "STACK")
+{ foreign "C" barf("STACK object entered!") never returns; }
 
-INFO_TABLE(stg_EVACUATED,1,0,EVACUATED,"EVACUATED","EVACUATED")
-{ foreign "C" barf("EVACUATED object entered!"); }
+INFO_TABLE(stg_RUBBISH_ENTRY, 0, 0, THUNK, "RUBBISH_ENTRY", "RUBBISH_ENTRY")
+{ foreign "C" barf("RUBBISH object entered!") never returns; }
 
 /* ----------------------------------------------------------------------------
    Weak pointers
@@ -421,17 +395,26 @@ INFO_TABLE(stg_EVACUATED,1,0,EVACUATED,"EVACUATED","EVACUATED")
    live weak pointers with dead ones).
    ------------------------------------------------------------------------- */
 
-INFO_TABLE(stg_WEAK,0,4,WEAK,"WEAK","WEAK")
-{ foreign "C" barf("WEAK object entered!"); }
+INFO_TABLE(stg_WEAK,1,4,WEAK,"WEAK","WEAK")
+{ foreign "C" barf("WEAK object entered!") never returns; }
 
 /*
  * It's important when turning an existing WEAK into a DEAD_WEAK
  * (which is what finalizeWeak# does) that we don't lose the link
  * field and break the linked list of weak pointers.  Hence, we give
- * DEAD_WEAK 4 non-pointer fields, the same as WEAK.
+ * DEAD_WEAK 5 non-pointer fields.
  */
-INFO_TABLE_CONSTR(stg_DEAD_WEAK,0,4,0,CONSTR,"DEAD_WEAK","DEAD_WEAK")
-{ foreign "C" barf("DEAD_WEAK object entered!"); }
+INFO_TABLE_CONSTR(stg_DEAD_WEAK,0,5,0,CONSTR,"DEAD_WEAK","DEAD_WEAK")
+{ foreign "C" barf("DEAD_WEAK object entered!") never returns; }
+
+/* ----------------------------------------------------------------------------
+   C finalizer lists
+
+   Singly linked lists that chain multiple C finalizers on a weak pointer.
+   ------------------------------------------------------------------------- */
+
+INFO_TABLE_CONSTR(stg_C_FINALIZER_LIST,1,4,0,CONSTR,"C_FINALIZER_LIST","C_FINALIZER_LIST")
+{ foreign "C" barf("C_FINALIZER_LIST object entered!") never returns; }
 
 /* ----------------------------------------------------------------------------
    NO_FINALIZER
@@ -441,7 +424,7 @@ INFO_TABLE_CONSTR(stg_DEAD_WEAK,0,4,0,CONSTR,"DEAD_WEAK","DEAD_WEAK")
    ------------------------------------------------------------------------- */
 
 INFO_TABLE_CONSTR(stg_NO_FINALIZER,0,0,0,CONSTR_NOCAF_STATIC,"NO_FINALIZER","NO_FINALIZER")
-{ foreign "C" barf("NO_FINALIZER object entered!"); }
+{ foreign "C" barf("NO_FINALIZER object entered!") never returns; }
 
 CLOSURE(stg_NO_FINALIZER_closure,stg_NO_FINALIZER);
 
@@ -449,8 +432,8 @@ CLOSURE(stg_NO_FINALIZER_closure,stg_NO_FINALIZER);
    Stable Names are unlifted too.
    ------------------------------------------------------------------------- */
 
-INFO_TABLE(stg_STABLE_NAME,0,1,STABLE_NAME,"STABLE_NAME","STABLE_NAME")
-{ foreign "C" barf("STABLE_NAME object entered!"); }
+INFO_TABLE(stg_STABLE_NAME,0,1,PRIM,"STABLE_NAME","STABLE_NAME")
+{ foreign "C" barf("STABLE_NAME object entered!") never returns; }
 
 /* ----------------------------------------------------------------------------
    MVars
@@ -459,45 +442,48 @@ INFO_TABLE(stg_STABLE_NAME,0,1,STABLE_NAME,"STABLE_NAME","STABLE_NAME")
    and entry code for each type.
    ------------------------------------------------------------------------- */
 
-INFO_TABLE(stg_FULL_MVAR,3,0,MVAR,"MVAR","MVAR")
-{ foreign "C" barf("FULL_MVAR object entered!"); }
+INFO_TABLE(stg_MVAR_CLEAN,3,0,MVAR_CLEAN,"MVAR","MVAR")
+{ foreign "C" barf("MVAR object entered!") never returns; }
 
-INFO_TABLE(stg_EMPTY_MVAR,3,0,MVAR,"MVAR","MVAR")
-{ foreign "C" barf("EMPTY_MVAR object entered!"); }
+INFO_TABLE(stg_MVAR_DIRTY,3,0,MVAR_DIRTY,"MVAR","MVAR")
+{ foreign "C" barf("MVAR object entered!") never returns; }
 
 /* -----------------------------------------------------------------------------
    STM
    -------------------------------------------------------------------------- */
 
-INFO_TABLE(stg_TVAR, 0, 0, TVAR, "TVAR", "TVAR")
-{ foreign "C" barf("TVAR object entered!"); }
+INFO_TABLE(stg_TVAR_CLEAN, 2, 1, TVAR, "TVAR", "TVAR")
+{ foreign "C" barf("TVAR_CLEAN object entered!") never returns; }
+
+INFO_TABLE(stg_TVAR_DIRTY, 2, 1, TVAR, "TVAR", "TVAR")
+{ foreign "C" barf("TVAR_DIRTY object entered!") never returns; }
 
-INFO_TABLE(stg_TVAR_WATCH_QUEUE, 0, 0, TVAR_WATCH_QUEUE, "TVAR_WATCH_QUEUE", "TVAR_WATCH_QUEUE")
-{ foreign "C" barf("TVAR_WATCH_QUEUE object entered!"); }
+INFO_TABLE(stg_TVAR_WATCH_QUEUE, 3, 0, MUT_PRIM, "TVAR_WATCH_QUEUE", "TVAR_WATCH_QUEUE")
+{ foreign "C" barf("TVAR_WATCH_QUEUE object entered!") never returns; }
 
-INFO_TABLE(stg_ATOMIC_INVARIANT, 0, 0, ATOMIC_INVARIANT, "ATOMIC_INVARIANT", "ATOMIC_INVARIANT")
-{ foreign "C" barf("ATOMIC_INVARIANT object entered!"); }
+INFO_TABLE(stg_ATOMIC_INVARIANT, 2, 1, MUT_PRIM, "ATOMIC_INVARIANT", "ATOMIC_INVARIANT")
+{ foreign "C" barf("ATOMIC_INVARIANT object entered!") never returns; }
 
-INFO_TABLE(stg_INVARIANT_CHECK_QUEUE, 0, 0, INVARIANT_CHECK_QUEUE, "INVARIANT_CHECK_QUEUE", "INVARIANT_CHECK_QUEUE")
-{ foreign "C" barf("INVARIANT_CHECK_QUEUE object entered!"); }
+INFO_TABLE(stg_INVARIANT_CHECK_QUEUE, 3, 0, MUT_PRIM, "INVARIANT_CHECK_QUEUE", "INVARIANT_CHECK_QUEUE")
+{ foreign "C" barf("INVARIANT_CHECK_QUEUE object entered!") never returns; }
 
 INFO_TABLE(stg_TREC_CHUNK, 0, 0, TREC_CHUNK, "TREC_CHUNK", "TREC_CHUNK")
-{ foreign "C" barf("TREC_CHUNK object entered!"); }
+{ foreign "C" barf("TREC_CHUNK object entered!") never returns; }
 
-INFO_TABLE(stg_TREC_HEADER, 0, 0, TREC_HEADER, "TREC_HEADER", "TREC_HEADER")
-{ foreign "C" barf("TREC_HEADER object entered!"); }
+INFO_TABLE(stg_TREC_HEADER, 3, 1, MUT_PRIM, "TREC_HEADER", "TREC_HEADER")
+{ foreign "C" barf("TREC_HEADER object entered!") never returns; }
 
 INFO_TABLE_CONSTR(stg_END_STM_WATCH_QUEUE,0,0,0,CONSTR_NOCAF_STATIC,"END_STM_WATCH_QUEUE","END_STM_WATCH_QUEUE")
-{ foreign "C" barf("END_STM_WATCH_QUEUE object entered!"); }
+{ foreign "C" barf("END_STM_WATCH_QUEUE object entered!") never returns; }
 
 INFO_TABLE_CONSTR(stg_END_INVARIANT_CHECK_QUEUE,0,0,0,CONSTR_NOCAF_STATIC,"END_INVARIANT_CHECK_QUEUE","END_INVARIANT_CHECK_QUEUE")
-{ foreign "C" barf("END_INVARIANT_CHECK_QUEUE object entered!"); }
+{ foreign "C" barf("END_INVARIANT_CHECK_QUEUE object entered!") never returns; }
 
 INFO_TABLE_CONSTR(stg_END_STM_CHUNK_LIST,0,0,0,CONSTR_NOCAF_STATIC,"END_STM_CHUNK_LIST","END_STM_CHUNK_LIST")
-{ foreign "C" barf("END_STM_CHUNK_LIST object entered!"); }
+{ foreign "C" barf("END_STM_CHUNK_LIST object entered!") never returns; }
 
 INFO_TABLE_CONSTR(stg_NO_TREC,0,0,0,CONSTR_NOCAF_STATIC,"NO_TREC","NO_TREC")
-{ foreign "C" barf("NO_TREC object entered!"); }
+{ foreign "C" barf("NO_TREC object entered!") never returns; }
 
 CLOSURE(stg_END_STM_WATCH_QUEUE_closure,stg_END_STM_WATCH_QUEUE);
 
@@ -508,6 +494,25 @@ CLOSURE(stg_END_STM_CHUNK_LIST_closure,stg_END_STM_CHUNK_LIST);
 CLOSURE(stg_NO_TREC_closure,stg_NO_TREC);
 
 /* ----------------------------------------------------------------------------
+   Messages
+   ------------------------------------------------------------------------- */
+
+// PRIM rather than CONSTR, because PRIM objects cannot be duplicated by the GC.
+
+INFO_TABLE_CONSTR(stg_MSG_TRY_WAKEUP,2,0,0,PRIM,"MSG_TRY_WAKEUP","MSG_TRY_WAKEUP")
+{ foreign "C" barf("MSG_TRY_WAKEUP object entered!") never returns; }
+
+INFO_TABLE_CONSTR(stg_MSG_THROWTO,4,0,0,PRIM,"MSG_THROWTO","MSG_THROWTO")
+{ foreign "C" barf("MSG_THROWTO object entered!") never returns; }
+
+INFO_TABLE_CONSTR(stg_MSG_BLACKHOLE,3,0,0,PRIM,"MSG_BLACKHOLE","MSG_BLACKHOLE")
+{ foreign "C" barf("MSG_BLACKHOLE object entered!") never returns; }
+
+// used to overwrite a MSG_THROWTO when the message has been used/revoked
+INFO_TABLE_CONSTR(stg_MSG_NULL,1,0,0,PRIM,"MSG_NULL","MSG_NULL")
+{ foreign "C" barf("MSG_NULL object entered!") never returns; }
+
+/* ----------------------------------------------------------------------------
    END_TSO_QUEUE
 
    This is a static nullary constructor (like []) that we use to mark the
@@ -515,21 +520,28 @@ CLOSURE(stg_NO_TREC_closure,stg_NO_TREC);
    ------------------------------------------------------------------------- */
 
 INFO_TABLE_CONSTR(stg_END_TSO_QUEUE,0,0,0,CONSTR_NOCAF_STATIC,"END_TSO_QUEUE","END_TSO_QUEUE")
-{ foreign "C" barf("END_TSO_QUEUE object entered!"); }
+{ foreign "C" barf("END_TSO_QUEUE object entered!") never returns; }
 
 CLOSURE(stg_END_TSO_QUEUE_closure,stg_END_TSO_QUEUE);
 
 /* ----------------------------------------------------------------------------
-   Exception lists
+   GCD_CAF
    ------------------------------------------------------------------------- */
 
-INFO_TABLE_CONSTR(stg_END_EXCEPTION_LIST,0,0,0,CONSTR_NOCAF_STATIC,"END_EXCEPTION_LIST","END_EXCEPTION_LIST")
-{ foreign "C" barf("END_EXCEPTION_LIST object entered!"); }
+INFO_TABLE_CONSTR(stg_GCD_CAF,0,0,0,CONSTR_NOCAF_STATIC,"GCD_CAF","GCD_CAF")
+{ foreign "C" barf("Evaluated a CAF that was GC'd!") never returns; }
 
-CLOSURE(stg_END_EXCEPTION_LIST_closure,stg_END_EXCEPTION_LIST);
+/* ----------------------------------------------------------------------------
+   STM_AWOKEN
+
+   This is a static nullary constructor (like []) that we use to mark a
+   thread waiting on an STM wakeup
+   ------------------------------------------------------------------------- */
+
+INFO_TABLE_CONSTR(stg_STM_AWOKEN,0,0,0,CONSTR_NOCAF_STATIC,"STM_AWOKEN","STM_AWOKEN")
+{ foreign "C" barf("STM_AWOKEN object entered!") never returns; }
 
-INFO_TABLE(stg_EXCEPTION_CONS,1,1,CONSTR,"EXCEPTION_CONS","EXCEPTION_CONS")
-{ foreign "C" barf("EXCEPTION_CONS object entered!"); }
+CLOSURE(stg_STM_AWOKEN_closure,stg_STM_AWOKEN);
 
 /* ----------------------------------------------------------------------------
    Arrays
@@ -537,75 +549,108 @@ INFO_TABLE(stg_EXCEPTION_CONS,1,1,CONSTR,"EXCEPTION_CONS","EXCEPTION_CONS")
    These come in two basic flavours: arrays of data (StgArrWords) and arrays of
    pointers (StgArrPtrs).  They all have a similar layout:
 
-       ___________________________
-       | Info | No. of | data....
-        |  Ptr | Words  |
-       ---------------------------
+   ___________________________
+   | Info | No. of | data....
+   |  Ptr | Words  |
+   ---------------------------
 
    These are *unpointed* objects: i.e. they cannot be entered.
 
    ------------------------------------------------------------------------- */
 
 INFO_TABLE(stg_ARR_WORDS, 0, 0, ARR_WORDS, "ARR_WORDS", "ARR_WORDS")
-{ foreign "C" barf("ARR_WORDS object entered!"); }
+{ foreign "C" barf("ARR_WORDS object entered!") never returns; }
 
 INFO_TABLE(stg_MUT_ARR_PTRS_CLEAN, 0, 0, MUT_ARR_PTRS_CLEAN, "MUT_ARR_PTRS_CLEAN", "MUT_ARR_PTRS_CLEAN")
-{ foreign "C" barf("MUT_ARR_PTRS_CLEAN object entered!"); }
+{ foreign "C" barf("MUT_ARR_PTRS_CLEAN object entered!") never returns; }
 
 INFO_TABLE(stg_MUT_ARR_PTRS_DIRTY, 0, 0, MUT_ARR_PTRS_DIRTY, "MUT_ARR_PTRS_DIRTY", "MUT_ARR_PTRS_DIRTY")
-{ foreign "C" barf("MUT_ARR_PTRS_DIRTY object entered!"); }
+{ foreign "C" barf("MUT_ARR_PTRS_DIRTY object entered!") never returns; }
 
 INFO_TABLE(stg_MUT_ARR_PTRS_FROZEN, 0, 0, MUT_ARR_PTRS_FROZEN, "MUT_ARR_PTRS_FROZEN", "MUT_ARR_PTRS_FROZEN")
-{ foreign "C" barf("MUT_ARR_PTRS_FROZEN object entered!"); }
+{ foreign "C" barf("MUT_ARR_PTRS_FROZEN object entered!") never returns; }
 
 INFO_TABLE(stg_MUT_ARR_PTRS_FROZEN0, 0, 0, MUT_ARR_PTRS_FROZEN0, "MUT_ARR_PTRS_FROZEN0", "MUT_ARR_PTRS_FROZEN0")
-{ foreign "C" barf("MUT_ARR_PTRS_FROZEN0 object entered!"); }
+{ foreign "C" barf("MUT_ARR_PTRS_FROZEN0 object entered!") never returns; }
+
+INFO_TABLE(stg_SMALL_MUT_ARR_PTRS_CLEAN, 0, 0, SMALL_MUT_ARR_PTRS_CLEAN, "SMALL_MUT_ARR_PTRS_CLEAN", "SMALL_MUT_ARR_PTRS_CLEAN")
+{ foreign "C" barf("SMALL_MUT_ARR_PTRS_CLEAN object entered!") never returns; }
+
+INFO_TABLE(stg_SMALL_MUT_ARR_PTRS_DIRTY, 0, 0, SMALL_MUT_ARR_PTRS_DIRTY, "SMALL_MUT_ARR_PTRS_DIRTY", "SMALL_MUT_ARR_PTRS_DIRTY")
+{ foreign "C" barf("SMALL_MUT_ARR_PTRS_DIRTY object entered!") never returns; }
+
+INFO_TABLE(stg_SMALL_MUT_ARR_PTRS_FROZEN, 0, 0, SMALL_MUT_ARR_PTRS_FROZEN, "SMALL_MUT_ARR_PTRS_FROZEN", "SMALL_MUT_ARR_PTRS_FROZEN")
+{ foreign "C" barf("SMALL_MUT_ARR_PTRS_FROZEN object entered!") never returns; }
+
+INFO_TABLE(stg_SMALL_MUT_ARR_PTRS_FROZEN0, 0, 0, SMALL_MUT_ARR_PTRS_FROZEN0, "SMALL_MUT_ARR_PTRS_FROZEN0", "SMALL_MUT_ARR_PTRS_FROZEN0")
+{ foreign "C" barf("SMALL_MUT_ARR_PTRS_FROZEN0 object entered!") never returns; }
 
 /* ----------------------------------------------------------------------------
    Mutable Variables
    ------------------------------------------------------------------------- */
 
 INFO_TABLE(stg_MUT_VAR_CLEAN, 1, 0, MUT_VAR_CLEAN, "MUT_VAR_CLEAN", "MUT_VAR_CLEAN")
-{ foreign "C" barf("MUT_VAR_CLEAN object entered!"); }
+{ foreign "C" barf("MUT_VAR_CLEAN object entered!") never returns; }
 INFO_TABLE(stg_MUT_VAR_DIRTY, 1, 0, MUT_VAR_DIRTY, "MUT_VAR_DIRTY", "MUT_VAR_DIRTY")
-{ foreign "C" barf("MUT_VAR_DIRTY object entered!"); }
+{ foreign "C" barf("MUT_VAR_DIRTY object entered!") never returns; }
 
 /* ----------------------------------------------------------------------------
    Dummy return closure
+
    Entering this closure will just return to the address on the top of the
    stack.  Useful for getting a thread in a canonical form where we can
    just enter the top stack word to start the thread.  (see deleteThread)
  * ------------------------------------------------------------------------- */
 
 INFO_TABLE( stg_dummy_ret, 0, 0, CONSTR_NOCAF_STATIC, "DUMMY_RET", "DUMMY_RET")
+    ()
 {
-  jump %ENTRY_CODE(Sp(0));
+    return ();
 }
 CLOSURE(stg_dummy_ret_closure,stg_dummy_ret);
 
 /* ----------------------------------------------------------------------------
-   CHARLIKE and INTLIKE closures.  
+   MVAR_TSO_QUEUE
+   ------------------------------------------------------------------------- */
+
+INFO_TABLE_CONSTR(stg_MVAR_TSO_QUEUE,2,0,0,PRIM,"MVAR_TSO_QUEUE","MVAR_TSO_QUEUE")
+{ foreign "C" barf("MVAR_TSO_QUEUE object entered!") never returns; }
+
+/* ----------------------------------------------------------------------------
+   COMPACT_NFDATA (a blob of data in NF with no outgoing pointers)
+
+   Just return immediately because the structure is in NF already
+   ------------------------------------------------------------------------- */
+
+INFO_TABLE( stg_COMPACT_NFDATA, 0, 0, COMPACT_NFDATA, "COMPACT_NFDATA", "COMPACT_NFDATA")
+    ()
+{
+    return ();
+}
+
+/* ----------------------------------------------------------------------------
+   CHARLIKE and INTLIKE closures.
 
    These are static representations of Chars and small Ints, so that
    we can remove dynamic Chars and Ints during garbage collection and
    replace them with references to the static objects.
    ------------------------------------------------------------------------- */
 
-#if defined(ENABLE_WIN32_DLL_SUPPORT)
+#if defined(COMPILING_WINDOWS_DLL)
 /*
- * When sticking the RTS in a DLL, we delay populating the
+ * When sticking the RTS in a Windows DLL, we delay populating the
  * Charlike and Intlike tables until load-time, which is only
  * when we've got the real addresses to the C# and I# closures.
  *
+ * -- this is currently broken BL 2009/11/14.
+ *    we don't rewrite to static closures at all with Windows DLLs.
  */
-static INFO_TBL_CONST StgInfoTable czh_static_info;
-static INFO_TBL_CONST StgInfoTable izh_static_info;
-#define Char_hash_static_info czh_static_info
-#define Int_hash_static_info izh_static_info
+// #warning Is this correct? _imp is a pointer!
+#define Char_hash_static_info _imp__ghczmprim_GHCziTypes_Czh_static_info
+#define Int_hash_static_info _imp__ghczmprim_GHCziTypes_Izh_static_info
 #else
-#define Char_hash_static_info base_GHCziBase_Czh_static
-#define Int_hash_static_info base_GHCziBase_Izh_static
+#define Char_hash_static_info ghczmprim_GHCziTypes_Czh_static_info
+#define Int_hash_static_info ghczmprim_GHCziTypes_Izh_static_info
 #endif
 
 
@@ -616,8 +661,7 @@ static INFO_TBL_CONST StgInfoTable izh_static_info;
  * on the fact that static closures live in the data section.
  */
 
-/* end the name with _closure, to convince the mangler this is a closure */
-
+#if !(defined(COMPILING_WINDOWS_DLL))
 section "data" {
  stg_CHARLIKE_closure:
     CHARLIKE_HDR(0)
@@ -880,7 +924,7 @@ section "data" {
 
 section "data" {
  stg_INTLIKE_closure:
-    INTLIKE_HDR(-16)   /* MIN_INTLIKE == -16 */
+    INTLIKE_HDR(-16) /* MIN_INTLIKE == -16 */
     INTLIKE_HDR(-15)
     INTLIKE_HDR(-14)
     INTLIKE_HDR(-13)
@@ -912,5 +956,7 @@ section "data" {
     INTLIKE_HDR(13)
     INTLIKE_HDR(14)
     INTLIKE_HDR(15)
-    INTLIKE_HDR(16)    /* MAX_INTLIKE == 16 */
+    INTLIKE_HDR(16)  /* MAX_INTLIKE == 16 */
 }
+
+#endif