path: root/rts/StgMiscClosures.cmm

/* ----------------------------------------------------------------------------
 *
 * (c) The GHC Team, 1998-2004
 *
 * Entry code for various built-in closure types.
 *
 * This file is written in a subset of C--, extended with various
 * features specific to GHC.  It is compiled by GHC directly.  For the
 * syntax of .cmm files, see the parser in ghc/compiler/cmm/CmmParse.y.
 *
 * --------------------------------------------------------------------------*/

#include "Cmm.h"

import pthread_mutex_lock;
import ghczmprim_GHCziTypes_Czh_info;
import ghczmprim_GHCziTypes_Izh_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 */
{
    unwind Sp = W_[Sp + WDS(2)];

    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!
}


INFO_TABLE_RET (stg_restore_cccs_eval, RET_SMALL, W_ info_ptr, W_ cccs)
    return (P_ ret)
{
    unwind Sp = Sp + WDS(2);
#if defined(PROFILING)
    CCCS = cccs;
#endif
    jump stg_ap_0_fast(ret);
}

/* ----------------------------------------------------------------------------
   Support for the bytecode interpreter.
   ------------------------------------------------------------------------- */

/* 7 bits of return code for constructors created by the interpreter. */
stg_interp_constr1_entry (P_ ret) { return (ret + 1); }
stg_interp_constr2_entry (P_ ret) { return (ret + 2); }
stg_interp_constr3_entry (P_ ret) { return (ret + 3); }
stg_interp_constr4_entry (P_ ret) { return (ret + 4); }
stg_interp_constr5_entry (P_ ret) { return (ret + 5); }
stg_interp_constr6_entry (P_ ret) { return (ret + 6); }
stg_interp_constr7_entry (P_ ret) { return (ret + 7); }

/* Some info tables to be used when compiled code returns a value to
   the interpreter, i.e. the interpreter pushes one of these onto the
   stack before entering a value.  What the code does is to
   impedance-match the compiled return convention (in R1p/R1n/F1/D1 etc) to
   the interpreter's convention (returned value is on top of stack),
   and then cause the scheduler to enter the interpreter.

   On entry, the stack (growing down) looks like this:

      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)
      * Yield, ie, go to the scheduler.

   Scheduler examines the t.o.s, discovers it is a BCO, and proceeds
   directly to the bytecode interpreter.  That pops the top element
   (the BCO, containing the return continuation), and interprets it.
   Net result: return continuation gets interpreted, with the
   following stack:

      ptr to this BCO
      ptr to the info table just jumped thru
      return value

   which is just what we want -- the "standard" return layout for the
   interpreter.  Hurrah!

   Don't ask me how unboxed tuple returns are supposed to work.  We
   haven't got a good story about that yet.
*/

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 [];
}

/*
 * 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_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_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_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_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_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_ret_v_info;
    jump stg_yield_to_interpreter [];
}

/*
 * Dummy info table pushed on the top of the stack when the interpreter
 * should apply the BCO on the stack to its arguments, also on the
 * 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 [];
}

/* ----------------------------------------------------------------------------
   Entry code for a BCO
   ------------------------------------------------------------------------- */

INFO_TABLE_FUN( stg_BCO, 3, 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 [];
}

/* ----------------------------------------------------------------------------
   Info tables for indirections.

   SPECIALISED INDIRECTIONS: we have a specialised indirection for direct returns,
   so that we can avoid entering
   the object when we know it points directly to a value.  The update
   code (Updates.cmm) updates objects with the appropriate kind of
   indirection.  We only do this for young-gen indirections.
   ------------------------------------------------------------------------- */

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 */
    node = UNTAG(StgInd_indirectee(node));
    TICK_ENT_VIA_NODE();
    jump %GET_ENTRY(node) (node);
}
#else
    /* explicit stack */
{
    TICK_ENT_DYN_IND(); /* tick */
    R1 = UNTAG(StgInd_indirectee(R1));
    TICK_ENT_VIA_NODE();
    jump %GET_ENTRY(R1) [R1];
}
#endif

INFO_TABLE(stg_IND_direct,1,0,IND,"IND","IND")
    (P_ node)
{
    TICK_ENT_DYN_IND(); /* tick */
    node = StgInd_indirectee(node);
    TICK_ENT_VIA_NODE();
    jump %ENTRY_CODE(Sp(0)) (node);
}

INFO_TABLE(stg_IND_STATIC,1,0,IND_STATIC,"IND_STATIC","IND_STATIC")
    /* explicit stack */
{
    TICK_ENT_STATIC_IND(); /* tick */
    R1 = UNTAG(StgInd_indirectee(R1));
    TICK_ENT_VIA_NODE();
    jump %GET_ENTRY(R1) [R1];
}

/* ----------------------------------------------------------------------------
   Black holes.

   Entering a black hole normally causes a cyclic data dependency, but
   in the concurrent world, black holes are synchronization points,
   and they are turned into blocking queues when there are threads
   waiting for the evaluation of the closure to finish.
   ------------------------------------------------------------------------- */

INFO_TABLE(stg_BLACKHOLE,1,0,BLACKHOLE,"BLACKHOLE","BLACKHOLE")
    (P_ node)
{
    W_ r, info, owner, bd;
    P_ p, bq, msg;

    TICK_ENT_DYN_IND(); /* tick */

retry:
    prim_read_barrier;
    p = StgInd_indirectee(node);
    if (GETTAG(p) != 0) {
        return (p);
    }

    info = StgHeader_info(p);
    prim_read_barrier;
    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().
        // See Note [BLACKHOLE pointing to IND] in sm/Evac.c
        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));

        MessageBlackHole_tso(msg) = CurrentTSO;
        MessageBlackHole_bh(msg) = node;
        SET_HDR(msg, stg_MSG_BLACKHOLE_info, CCS_SYSTEM);
        // messageBlackHole has appropriate memory barriers when this object is exposed.
        // See Note [Heap memory barriers].

        (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);
    }
}

// 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)
{
    jump ENTRY_LBL(stg_BLACKHOLE) (node);
}

// EAGER_BLACKHOLE exists for the same reason as CAF_BLACKHOLE (see above).
INFO_TABLE(__stg_EAGER_BLACKHOLE,1,0,BLACKHOLE,"BLACKHOLE","BLACKHOLE")
    (P_ node)
{
    jump ENTRY_LBL(stg_BLACKHOLE) (node);
}

INFO_TABLE(stg_BLOCKING_QUEUE_CLEAN,4,0,BLOCKING_QUEUE,"BLOCKING_QUEUE","BLOCKING_QUEUE")
{ foreign "C" barf("BLOCKING_QUEUE_CLEAN object (%p) entered!", R1) never returns; }


INFO_TABLE(stg_BLOCKING_QUEUE_DIRTY,4,0,BLOCKING_QUEUE,"BLOCKING_QUEUE","BLOCKING_QUEUE")
{ foreign "C" barf("BLOCKING_QUEUE_DIRTY object (%p) entered!", R1) never returns; }


/* ----------------------------------------------------------------------------
   Whiteholes are used for the "locked" state of a closure (see lockClosure())
   ------------------------------------------------------------------------- */

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) {
#if defined(PROF_SPIN)
        W_[whitehole_lockClosure_spin] =
            W_[whitehole_lockClosure_spin] + 1;
#endif
        i = i + 1;
        if (i == SPIN_COUNT) {
            i = 0;
#if defined(PROF_SPIN)
            W_[whitehole_lockClosure_yield] =
                W_[whitehole_lockClosure_yield] + 1;
#endif
            ccall yieldThread();
        }
        // TODO: We should busy_wait_nop() here, but that's not currently
        // defined in CMM.
        goto loop;
    }
    jump %ENTRY_CODE(info) (node);
#else
    ccall barf("WHITEHOLE object (%p) entered!", R1) never returns;
#endif
}

/* ----------------------------------------------------------------------------
   Some static info tables for things that don't get entered, and
   therefore don't need entry code (i.e. boxed but unpointed objects)
   NON_ENTERABLE_ENTRY_CODE now defined at the beginning of the file
   ------------------------------------------------------------------------- */

INFO_TABLE(stg_TSO, 0,0,TSO, "TSO", "TSO")
{ foreign "C" barf("TSO object (%p) entered!", R1) never returns; }

INFO_TABLE(stg_STACK, 0,0, STACK, "STACK", "STACK")
{ foreign "C" barf("STACK object (%p) entered!", R1) never returns; }

/* ----------------------------------------------------------------------------
   Weak pointers

   Live weak pointers have a special closure type.  Dead ones are just
   nullary constructors (although they live on the heap - we overwrite
   live weak pointers with dead ones).
   ------------------------------------------------------------------------- */

INFO_TABLE(stg_WEAK,1,4,WEAK,"WEAK","WEAK")
{ foreign "C" barf("WEAK object (%p) entered!", R1) 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 5 non-pointer fields.
 */
INFO_TABLE_CONSTR(stg_DEAD_WEAK,0,5,0,CONSTR,"DEAD_WEAK","DEAD_WEAK")
{ foreign "C" barf("DEAD_WEAK object (%p) entered!", R1) 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 (%p) entered!", R1) never returns; }

/* ----------------------------------------------------------------------------
   NO_FINALIZER

   This is a static nullary constructor (like []) that we use to mark an empty
   finalizer in a weak pointer object.
   ------------------------------------------------------------------------- */

INFO_TABLE_CONSTR(stg_NO_FINALIZER,0,0,0,CONSTR_NOCAF,"NO_FINALIZER","NO_FINALIZER")
{ foreign "C" barf("NO_FINALIZER object (%p) entered!", R1) never returns; }

CLOSURE(stg_NO_FINALIZER_closure,stg_NO_FINALIZER);

/* ----------------------------------------------------------------------------
   Stable Names are unlifted too.
   ------------------------------------------------------------------------- */

INFO_TABLE(stg_STABLE_NAME,0,1,PRIM,"STABLE_NAME","STABLE_NAME")
{ foreign "C" barf("STABLE_NAME object (%p) entered!", R1) never returns; }

/* ----------------------------------------------------------------------------
   MVars

   There are two kinds of these: full and empty.  We need an info table
   and entry code for each type.
   ------------------------------------------------------------------------- */

INFO_TABLE(stg_MVAR_CLEAN,3,0,MVAR_CLEAN,"MVAR","MVAR")
{ foreign "C" barf("MVAR object (%p) entered!", R1) never returns; }

INFO_TABLE(stg_MVAR_DIRTY,3,0,MVAR_DIRTY,"MVAR","MVAR")
{ foreign "C" barf("MVAR object (%p) entered!", R1) never returns; }

/* -----------------------------------------------------------------------------
   STM
   -------------------------------------------------------------------------- */

INFO_TABLE(stg_TVAR_CLEAN, 2, 1, TVAR, "TVAR", "TVAR")
{ foreign "C" barf("TVAR_CLEAN object (%p) entered!", R1) never returns; }

INFO_TABLE(stg_TVAR_DIRTY, 2, 1, TVAR, "TVAR", "TVAR")
{ foreign "C" barf("TVAR_DIRTY object (%p) entered!", R1) never returns; }

INFO_TABLE(stg_TVAR_WATCH_QUEUE, 3, 0, MUT_PRIM, "TVAR_WATCH_QUEUE", "TVAR_WATCH_QUEUE")
{ foreign "C" barf("TVAR_WATCH_QUEUE object (%p) entered!", R1) never returns; }

INFO_TABLE(stg_TREC_CHUNK, 0, 0, TREC_CHUNK, "TREC_CHUNK", "TREC_CHUNK")
{ foreign "C" barf("TREC_CHUNK object (%p) entered!", R1) never returns; }

INFO_TABLE(stg_TREC_HEADER, 2, 1, MUT_PRIM, "TREC_HEADER", "TREC_HEADER")
{ foreign "C" barf("TREC_HEADER object (%p) entered!", R1) never returns; }

INFO_TABLE_CONSTR(stg_END_STM_WATCH_QUEUE,0,0,0,CONSTR_NOCAF,"END_STM_WATCH_QUEUE","END_STM_WATCH_QUEUE")
{ foreign "C" barf("END_STM_WATCH_QUEUE object (%p) entered!", R1) never returns; }

INFO_TABLE_CONSTR(stg_END_STM_CHUNK_LIST,0,0,0,CONSTR_NOCAF,"END_STM_CHUNK_LIST","END_STM_CHUNK_LIST")
{ foreign "C" barf("END_STM_CHUNK_LIST object (%p) entered!", R1) never returns; }

INFO_TABLE_CONSTR(stg_NO_TREC,0,0,0,CONSTR_NOCAF,"NO_TREC","NO_TREC")
{ foreign "C" barf("NO_TREC object (%p) entered!", R1) never returns; }

CLOSURE(stg_END_STM_WATCH_QUEUE_closure,stg_END_STM_WATCH_QUEUE);

CLOSURE(stg_END_STM_CHUNK_LIST_closure,stg_END_STM_CHUNK_LIST);

CLOSURE(stg_NO_TREC_closure,stg_NO_TREC);

/* ----------------------------------------------------------------------------
   SRTs

   See Note [SRTs] in compiler/cmm/CmmBuildInfoTable.hs
   ------------------------------------------------------------------------- */

INFO_TABLE_CONSTR(stg_SRT_1, 1, 0, 0, CONSTR_1_0, "SRT_1", "SRT_1")
{ foreign "C" barf("SRT_1 object (%p) entered!", R1) never returns; }

INFO_TABLE_CONSTR(stg_SRT_2, 2, 0, 0, CONSTR_2_0, "SRT_2", "SRT_2")
{ foreign "C" barf("SRT_2 object (%p) entered!", R1) never returns; }

INFO_TABLE_CONSTR(stg_SRT_3, 3, 0, 0, CONSTR, "SRT_3", "SRT_3")
{ foreign "C" barf("SRT_3 object (%p) entered!", R1) never returns; }

INFO_TABLE_CONSTR(stg_SRT_4, 4, 0, 0, CONSTR, "SRT_4", "SRT_4")
{ foreign "C" barf("SRT_4 object (%p) entered!", R1) never returns; }

INFO_TABLE_CONSTR(stg_SRT_5, 5, 0, 0, CONSTR, "SRT_5", "SRT_5")
{ foreign "C" barf("SRT_5 object (%p) entered!", R1) never returns; }

INFO_TABLE_CONSTR(stg_SRT_6, 6, 0, 0, CONSTR, "SRT_6", "SRT_6")
{ foreign "C" barf("SRT_6 object (%p) entered!", R1) never returns; }

INFO_TABLE_CONSTR(stg_SRT_7, 7, 0, 0, CONSTR, "SRT_7", "SRT_7")
{ foreign "C" barf("SRT_7 object (%p) entered!", R1) never returns; }

INFO_TABLE_CONSTR(stg_SRT_8, 8, 0, 0, CONSTR, "SRT_8", "SRT_8")
{ foreign "C" barf("SRT_8 object (%p) entered!", R1) never returns; }

INFO_TABLE_CONSTR(stg_SRT_9, 9, 0, 0, CONSTR, "SRT_9", "SRT_9")
{ foreign "C" barf("SRT_9 object (%p) entered!", R1) never returns; }

INFO_TABLE_CONSTR(stg_SRT_10, 10, 0, 0, CONSTR, "SRT_10", "SRT_10")
{ foreign "C" barf("SRT_10 object (%p) entered!", R1) never returns; }

INFO_TABLE_CONSTR(stg_SRT_11, 11, 0, 0, CONSTR, "SRT_11", "SRT_11")
{ foreign "C" barf("SRT_11 object (%p) entered!", R1) never returns; }

INFO_TABLE_CONSTR(stg_SRT_12, 12, 0, 0, CONSTR, "SRT_12", "SRT_12")
{ foreign "C" barf("SRT_12 object (%p) entered!", R1) never returns; }

INFO_TABLE_CONSTR(stg_SRT_13, 13, 0, 0, CONSTR, "SRT_13", "SRT_13")
{ foreign "C" barf("SRT_13 object (%p) entered!", R1) never returns; }

INFO_TABLE_CONSTR(stg_SRT_14, 14, 0, 0, CONSTR, "SRT_14", "SRT_14")
{ foreign "C" barf("SRT_14 object (%p) entered!", R1) never returns; }

INFO_TABLE_CONSTR(stg_SRT_15, 15, 0, 0, CONSTR, "SRT_15", "SRT_15")
{ foreign "C" barf("SRT_15 object (%p) entered!", R1) never returns; }

INFO_TABLE_CONSTR(stg_SRT_16, 16, 0, 0, CONSTR, "SRT_16", "SRT_16")
{ foreign "C" barf("SRT_16 object (%p) entered!", R1) never returns; }

/* ---------------------------------------------------------------------------   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 (%p) entered!", R1) never returns; }

INFO_TABLE_CONSTR(stg_MSG_THROWTO,4,0,0,PRIM,"MSG_THROWTO","MSG_THROWTO")
{ foreign "C" barf("MSG_THROWTO object (%p) entered!", R1) never returns; }

INFO_TABLE_CONSTR(stg_MSG_BLACKHOLE,3,0,0,PRIM,"MSG_BLACKHOLE","MSG_BLACKHOLE")
{ foreign "C" barf("MSG_BLACKHOLE object (%p) entered!", R1) 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 (%p) entered!", R1) never returns; }

/* ----------------------------------------------------------------------------
   END_TSO_QUEUE

   This is a static nullary constructor (like []) that we use to mark the
   end of a linked TSO queue.
   ------------------------------------------------------------------------- */

INFO_TABLE_CONSTR(stg_END_TSO_QUEUE,0,0,0,CONSTR_NOCAF,"END_TSO_QUEUE","END_TSO_QUEUE")
{ foreign "C" barf("END_TSO_QUEUE object (%p) entered!", R1) never returns; }

CLOSURE(stg_END_TSO_QUEUE_closure,stg_END_TSO_QUEUE);

/* ----------------------------------------------------------------------------
   GCD_CAF
   ------------------------------------------------------------------------- */

INFO_TABLE_CONSTR(stg_GCD_CAF,0,0,0,CONSTR_NOCAF,"GCD_CAF","GCD_CAF")
{ foreign "C" barf("Evaluated a CAF (%p) that was GC'd!", R1) never returns; }

/* ----------------------------------------------------------------------------
   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,"STM_AWOKEN","STM_AWOKEN")
{ foreign "C" barf("STM_AWOKEN object (%p) entered!", R1) never returns; }

CLOSURE(stg_STM_AWOKEN_closure,stg_STM_AWOKEN);

/* ----------------------------------------------------------------------------
   Arrays

   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  |
   ---------------------------

   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 (%p) entered!", R1) 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 (%p) entered!", R1) 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 (%p) entered!", R1) never returns; }

INFO_TABLE(stg_MUT_ARR_PTRS_FROZEN_CLEAN, 0, 0, MUT_ARR_PTRS_FROZEN_CLEAN, "MUT_ARR_PTRS_FROZEN_CLEAN", "MUT_ARR_PTRS_FROZEN_CLEAN")
{ foreign "C" barf("MUT_ARR_PTRS_FROZEN_CLEAN object (%p) entered!", R1) never returns; }

INFO_TABLE(stg_MUT_ARR_PTRS_FROZEN_DIRTY, 0, 0, MUT_ARR_PTRS_FROZEN_DIRTY, "MUT_ARR_PTRS_FROZEN_DIRTY", "MUT_ARR_PTRS_FROZEN_DIRTY")
{ foreign "C" barf("MUT_ARR_PTRS_FROZEN_DIRTY object (%p) entered!", R1) 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 (%p) entered!", R1) 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 (%p) entered!", R1) never returns; }

INFO_TABLE(stg_SMALL_MUT_ARR_PTRS_FROZEN_CLEAN, 0, 0, SMALL_MUT_ARR_PTRS_FROZEN_CLEAN, "SMALL_MUT_ARR_PTRS_FROZEN_CLEAN", "SMALL_MUT_ARR_PTRS_FROZEN_CLEAN")
{ foreign "C" barf("SMALL_MUT_ARR_PTRS_FROZEN_CLEAN object (%p) entered!", R1) never returns; }

INFO_TABLE(stg_SMALL_MUT_ARR_PTRS_FROZEN_DIRTY, 0, 0, SMALL_MUT_ARR_PTRS_FROZEN_DIRTY, "SMALL_MUT_ARR_PTRS_FROZEN_DIRTY", "SMALL_MUT_ARR_PTRS_FROZEN_DIRTY")
{ foreign "C" barf("SMALL_MUT_ARR_PTRS_FROZEN_DIRTY object (%p) entered!", R1) 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 (%p) entered!", R1) 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 (%p) entered!", R1) 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, "DUMMY_RET", "DUMMY_RET")
    ()
{
    return ();
}
CLOSURE(stg_dummy_ret_closure,stg_dummy_ret);

/* ----------------------------------------------------------------------------
   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 (%p) entered!", R1) never returns; }

/* ----------------------------------------------------------------------------
   COMPACT_NFDATA (a blob of data in NF with no outgoing pointers)

   See Note [Compact Normal Forms] in sm/CNF.c

   CLEAN/DIRTY refer to the state of the "hash" field: DIRTY means that
   compaction is in progress and the hash table needs to be scanned by the GC.
   ------------------------------------------------------------------------- */

INFO_TABLE( stg_COMPACT_NFDATA_CLEAN, 0, 8, COMPACT_NFDATA, "COMPACT_NFDATA", "COMPACT_NFDATA")
    ()
{ foreign "C" barf("COMPACT_NFDATA_CLEAN object (%p) entered!", R1) never returns; }

INFO_TABLE( stg_COMPACT_NFDATA_DIRTY, 0, 8, COMPACT_NFDATA, "COMPACT_NFDATA", "COMPACT_NFDATA")
    ()
{ foreign "C" barf("COMPACT_NFDATA_DIRTY object (%p) entered!", R1) never returns; }

/* ----------------------------------------------------------------------------
   Note [INTLIKE closures]
   ~~~~~~~~~~~~~~~~~~~~~~~

   These are static representations of Closures like small Ints, Chars and other
   compatible closures so that we can remove their dynamic versions during garbage
   collection and replace them with references to the static objects.

   We do so by looking for CONSTR_0_1 closures checking their payload and tags.
   If we have a matching static closure we replace the reference to the dynamic object
   with a reference to a static closure with the same payload.

   A matching closure must have:
   * A tag of 1
   * Closure type CONSTR_0_1
   * MIN_INTLIKE <= payload <= MAX_INTLIKE

   This is because we only preallocate closures with tag 1 (1-based tag) and payloads in the range of
   MIN_INTLIKE to MAX_INTLIKE.

   This works since any closure of type `CONSTR_0_1` for non-profiling builds
   has the same info table content if it has the same tag.
   This follows from the fact that info tables describe:
   * closure type
   * heap layout
   * pointer tag

   The fact that we do so is only observeable if users manually inspect and compare
   the info table pointers of objects. Something GHC makes no guarantees about.

   In profiled builds the info tables also include type and constructor name.

   This difference does not show up in heap profiles, as static objects are not included
   in the heap census. If users manually inspect the heap of a profiled program then
   this could be observed when reading the constructor name or type from the info table.
   In this case instead of the original constructor/type name the one of the static closure
   will show up. For this reason we rewrite closures to the type "StaticBoxedWordType"
   instead of simply using Int closures, as this is hopefully less confusing in these cases.
   The type StaticBoxedWordType is defined in ghc-prim for the benefit of this
   substitution.

   This works for GHC defined types like Word/Int/Char/Int8/... and user defined
   types of the same shape.

   ------------------------------------------------------------------------- */

#if defined(COMPILING_WINDOWS_DLL)
/*
 * 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.
 */
// #warning Is this correct? _imp is a pointer!
#define Int_hash_con_info _imp__ghczmprim_GHCziTypes_Izh_con_info
#define ConstILike_hash_con_info _imp__ghczmprim_GHCziIntlike_ConstILikezh_con_info
#else
#define Int_hash_con_info ghczmprim_GHCziTypes_Izh_con_info
#define ConstILike_hash_con_info ghczmprim_GHCziIntlike_ConstILikezh_con_info

#endif

#define INTLIKE_HDR(n)   CLOSURE(ConstILike_hash_con_info, n)

#if !(defined(COMPILING_WINDOWS_DLL))
section "data" {
 stg_INTLIKE_closure:
    INTLIKE_HDR(-16) /* MIN_INTLIKE == -16 */
    INTLIKE_HDR(-15)
    INTLIKE_HDR(-14)
    INTLIKE_HDR(-13)
    INTLIKE_HDR(-12)
    INTLIKE_HDR(-11)
    INTLIKE_HDR(-10)
    INTLIKE_HDR(-9)
    INTLIKE_HDR(-8)
    INTLIKE_HDR(-7)
    INTLIKE_HDR(-6)
    INTLIKE_HDR(-5)
    INTLIKE_HDR(-4)
    INTLIKE_HDR(-3)
    INTLIKE_HDR(-2)
    INTLIKE_HDR(-1)
    INTLIKE_HDR(0)
    INTLIKE_HDR(1)
    INTLIKE_HDR(2)
    INTLIKE_HDR(3)
    INTLIKE_HDR(4)
    INTLIKE_HDR(5)
    INTLIKE_HDR(6)
    INTLIKE_HDR(7)
    INTLIKE_HDR(8)
    INTLIKE_HDR(9)
    INTLIKE_HDR(10)
    INTLIKE_HDR(11)
    INTLIKE_HDR(12)
    INTLIKE_HDR(13)
    INTLIKE_HDR(14)
    INTLIKE_HDR(15)
    INTLIKE_HDR(16)
    INTLIKE_HDR(17)
    INTLIKE_HDR(18)
    INTLIKE_HDR(19)
    INTLIKE_HDR(20)
    INTLIKE_HDR(21)
    INTLIKE_HDR(22)
    INTLIKE_HDR(23)
    INTLIKE_HDR(24)
    INTLIKE_HDR(25)
    INTLIKE_HDR(26)
    INTLIKE_HDR(27)
    INTLIKE_HDR(28)
    INTLIKE_HDR(29)
    INTLIKE_HDR(30)
    INTLIKE_HDR(31)
    INTLIKE_HDR(32)
    INTLIKE_HDR(33)
    INTLIKE_HDR(34)
    INTLIKE_HDR(35)
    INTLIKE_HDR(36)
    INTLIKE_HDR(37)
    INTLIKE_HDR(38)
    INTLIKE_HDR(39)
    INTLIKE_HDR(40)
    INTLIKE_HDR(41)
    INTLIKE_HDR(42)
    INTLIKE_HDR(43)
    INTLIKE_HDR(44)
    INTLIKE_HDR(45)
    INTLIKE_HDR(46)
    INTLIKE_HDR(47)
    INTLIKE_HDR(48)
    INTLIKE_HDR(49)
    INTLIKE_HDR(50)
    INTLIKE_HDR(51)
    INTLIKE_HDR(52)
    INTLIKE_HDR(53)
    INTLIKE_HDR(54)
    INTLIKE_HDR(55)
    INTLIKE_HDR(56)
    INTLIKE_HDR(57)
    INTLIKE_HDR(58)
    INTLIKE_HDR(59)
    INTLIKE_HDR(60)
    INTLIKE_HDR(61)
    INTLIKE_HDR(62)
    INTLIKE_HDR(63)
    INTLIKE_HDR(64)
    INTLIKE_HDR(65)
    INTLIKE_HDR(66)
    INTLIKE_HDR(67)
    INTLIKE_HDR(68)
    INTLIKE_HDR(69)
    INTLIKE_HDR(70)
    INTLIKE_HDR(71)
    INTLIKE_HDR(72)
    INTLIKE_HDR(73)
    INTLIKE_HDR(74)
    INTLIKE_HDR(75)
    INTLIKE_HDR(76)
    INTLIKE_HDR(77)
    INTLIKE_HDR(78)
    INTLIKE_HDR(79)
    INTLIKE_HDR(80)
    INTLIKE_HDR(81)
    INTLIKE_HDR(82)
    INTLIKE_HDR(83)
    INTLIKE_HDR(84)
    INTLIKE_HDR(85)
    INTLIKE_HDR(86)
    INTLIKE_HDR(87)
    INTLIKE_HDR(88)
    INTLIKE_HDR(89)
    INTLIKE_HDR(90)
    INTLIKE_HDR(91)
    INTLIKE_HDR(92)
    INTLIKE_HDR(93)
    INTLIKE_HDR(94)
    INTLIKE_HDR(95)
    INTLIKE_HDR(96)
    INTLIKE_HDR(97)
    INTLIKE_HDR(98)
    INTLIKE_HDR(99)
    INTLIKE_HDR(100)
    INTLIKE_HDR(101)
    INTLIKE_HDR(102)
    INTLIKE_HDR(103)
    INTLIKE_HDR(104)
    INTLIKE_HDR(105)
    INTLIKE_HDR(106)
    INTLIKE_HDR(107)
    INTLIKE_HDR(108)
    INTLIKE_HDR(109)
    INTLIKE_HDR(110)
    INTLIKE_HDR(111)
    INTLIKE_HDR(112)
    INTLIKE_HDR(113)
    INTLIKE_HDR(114)
    INTLIKE_HDR(115)
    INTLIKE_HDR(116)
    INTLIKE_HDR(117)
    INTLIKE_HDR(118)
    INTLIKE_HDR(119)
    INTLIKE_HDR(120)
    INTLIKE_HDR(121)
    INTLIKE_HDR(122)
    INTLIKE_HDR(123)
    INTLIKE_HDR(124)
    INTLIKE_HDR(125)
    INTLIKE_HDR(126)
    INTLIKE_HDR(127)
    INTLIKE_HDR(128)
    INTLIKE_HDR(129)
    INTLIKE_HDR(130)
    INTLIKE_HDR(131)
    INTLIKE_HDR(132)
    INTLIKE_HDR(133)
    INTLIKE_HDR(134)
    INTLIKE_HDR(135)
    INTLIKE_HDR(136)
    INTLIKE_HDR(137)
    INTLIKE_HDR(138)
    INTLIKE_HDR(139)
    INTLIKE_HDR(140)
    INTLIKE_HDR(141)
    INTLIKE_HDR(142)
    INTLIKE_HDR(143)
    INTLIKE_HDR(144)
    INTLIKE_HDR(145)
    INTLIKE_HDR(146)
    INTLIKE_HDR(147)
    INTLIKE_HDR(148)
    INTLIKE_HDR(149)
    INTLIKE_HDR(150)
    INTLIKE_HDR(151)
    INTLIKE_HDR(152)
    INTLIKE_HDR(153)
    INTLIKE_HDR(154)
    INTLIKE_HDR(155)
    INTLIKE_HDR(156)
    INTLIKE_HDR(157)
    INTLIKE_HDR(158)
    INTLIKE_HDR(159)
    INTLIKE_HDR(160)
    INTLIKE_HDR(161)
    INTLIKE_HDR(162)
    INTLIKE_HDR(163)
    INTLIKE_HDR(164)
    INTLIKE_HDR(165)
    INTLIKE_HDR(166)
    INTLIKE_HDR(167)
    INTLIKE_HDR(168)
    INTLIKE_HDR(169)
    INTLIKE_HDR(170)
    INTLIKE_HDR(171)
    INTLIKE_HDR(172)
    INTLIKE_HDR(173)
    INTLIKE_HDR(174)
    INTLIKE_HDR(175)
    INTLIKE_HDR(176)
    INTLIKE_HDR(177)
    INTLIKE_HDR(178)
    INTLIKE_HDR(179)
    INTLIKE_HDR(180)
    INTLIKE_HDR(181)
    INTLIKE_HDR(182)
    INTLIKE_HDR(183)
    INTLIKE_HDR(184)
    INTLIKE_HDR(185)
    INTLIKE_HDR(186)
    INTLIKE_HDR(187)
    INTLIKE_HDR(188)
    INTLIKE_HDR(189)
    INTLIKE_HDR(190)
    INTLIKE_HDR(191)
    INTLIKE_HDR(192)
    INTLIKE_HDR(193)
    INTLIKE_HDR(194)
    INTLIKE_HDR(195)
    INTLIKE_HDR(196)
    INTLIKE_HDR(197)
    INTLIKE_HDR(198)
    INTLIKE_HDR(199)
    INTLIKE_HDR(200)
    INTLIKE_HDR(201)
    INTLIKE_HDR(202)
    INTLIKE_HDR(203)
    INTLIKE_HDR(204)
    INTLIKE_HDR(205)
    INTLIKE_HDR(206)
    INTLIKE_HDR(207)
    INTLIKE_HDR(208)
    INTLIKE_HDR(209)
    INTLIKE_HDR(210)
    INTLIKE_HDR(211)
    INTLIKE_HDR(212)
    INTLIKE_HDR(213)
    INTLIKE_HDR(214)
    INTLIKE_HDR(215)
    INTLIKE_HDR(216)
    INTLIKE_HDR(217)
    INTLIKE_HDR(218)
    INTLIKE_HDR(219)
    INTLIKE_HDR(220)
    INTLIKE_HDR(221)
    INTLIKE_HDR(222)
    INTLIKE_HDR(223)
    INTLIKE_HDR(224)
    INTLIKE_HDR(225)
    INTLIKE_HDR(226)
    INTLIKE_HDR(227)
    INTLIKE_HDR(228)
    INTLIKE_HDR(229)
    INTLIKE_HDR(230)
    INTLIKE_HDR(231)
    INTLIKE_HDR(232)
    INTLIKE_HDR(233)
    INTLIKE_HDR(234)
    INTLIKE_HDR(235)
    INTLIKE_HDR(236)
    INTLIKE_HDR(237)
    INTLIKE_HDR(238)
    INTLIKE_HDR(239)
    INTLIKE_HDR(240)
    INTLIKE_HDR(241)
    INTLIKE_HDR(242)
    INTLIKE_HDR(243)
    INTLIKE_HDR(244)
    INTLIKE_HDR(245)
    INTLIKE_HDR(246)
    INTLIKE_HDR(247)
    INTLIKE_HDR(248)
    INTLIKE_HDR(249)
    INTLIKE_HDR(250)
    INTLIKE_HDR(251)
    INTLIKE_HDR(252)
    INTLIKE_HDR(253)
    INTLIKE_HDR(254)
    INTLIKE_HDR(255)    /* MAX_INTLIKE == 255
                         See #16961 for why 255 */
}

#endif