Esempio n. 1
0
static
IRSB* drd_instrument(VgCallbackClosure* const closure,
                     IRSB* const bb_in,
                     VexGuestLayout* const layout,
                     VexGuestExtents* const vge, 
                     IRType const gWordTy,
                     IRType const hWordTy)
{
  IRDirty* di;
  Int      i;
  IRSB*    bb;
  IRExpr** argv;
  Bool     instrument = True;
  Bool     bus_locked = False;

  /* Set up BB */
  bb           = emptyIRSB();
  bb->tyenv    = deepCopyIRTypeEnv(bb_in->tyenv);
  bb->next     = deepCopyIRExpr(bb_in->next);
  bb->jumpkind = bb_in->jumpkind;

  for (i = 0; i < bb_in->stmts_used; i++)
  {
    IRStmt* const st = bb_in->stmts[i];
    tl_assert(st);
    if (st->tag == Ist_NoOp)
      continue;

    switch (st->tag)
    {
    /* Note: the code for not instrumenting the code in .plt          */
    /* sections is only necessary on CentOS 3.0 x86 (kernel 2.4.21    */
    /* + glibc 2.3.2 + NPTL 0.60 + binutils 2.14.90.0.4).             */
    /* This is because on this platform dynamic library symbols are   */
    /* relocated in another way than by later binutils versions. The  */
    /* linker e.g. does not generate .got.plt sections on CentOS 3.0. */
    case Ist_IMark:
      instrument = VG_(seginfo_sect_kind)(NULL, 0, st->Ist.IMark.addr)
        != Vg_SectPLT;
      addStmtToIRSB(bb, st);
      break;

    case Ist_MBE:
      switch (st->Ist.MBE.event)
      {
      case Imbe_Fence:
        break; /* not interesting */
      case Imbe_BusLock:
      case Imbe_SnoopedStoreBegin:
        tl_assert(! bus_locked);
        bus_locked = True;
        break;
      case Imbe_BusUnlock:
      case Imbe_SnoopedStoreEnd:
        tl_assert(bus_locked);
        bus_locked = False;
        break;
      default:
        tl_assert(0);
      }
      addStmtToIRSB(bb, st);
      break;

    case Ist_Store:
      if (instrument && ! bus_locked)
      {
        instrument_store(bb,
                         st->Ist.Store.addr,
                         sizeofIRType(typeOfIRExpr(bb->tyenv,
                                                   st->Ist.Store.data)));
      }
      addStmtToIRSB(bb, st);
      break;

    case Ist_WrTmp:
      if (instrument)
      {
        const IRExpr* const data = st->Ist.WrTmp.data;
        if (data->tag == Iex_Load)
        {
          instrument_load(bb,
                          data->Iex.Load.addr,
                          sizeofIRType(data->Iex.Load.ty));
        }
      }
      addStmtToIRSB(bb, st);
      break;

    case Ist_Dirty:
      if (instrument)
      {
        IRDirty* d = st->Ist.Dirty.details;
        IREffect const mFx = d->mFx;
        switch (mFx) {
        case Ifx_None:
          break;
        case Ifx_Read:
        case Ifx_Write:
        case Ifx_Modify:
          tl_assert(d->mAddr);
          tl_assert(d->mSize > 0);
          argv = mkIRExprVec_2(d->mAddr, mkIRExpr_HWord(d->mSize));
          if (mFx == Ifx_Read || mFx == Ifx_Modify) {
            di = unsafeIRDirty_0_N(
                                   /*regparms*/2,
                                   "drd_trace_load",
                                   VG_(fnptr_to_fnentry)(drd_trace_load),
                                   argv);
            addStmtToIRSB(bb, IRStmt_Dirty(di));
          }
          if ((mFx == Ifx_Write || mFx == Ifx_Modify)
              && ! bus_locked)
          {
            di = unsafeIRDirty_0_N(
                                   /*regparms*/2,
                                   "drd_trace_store",
                                   VG_(fnptr_to_fnentry)(drd_trace_store),
                                   argv);
            addStmtToIRSB(bb, IRStmt_Dirty(di));
          }
          break;
        default:
          tl_assert(0);
        }
      }
      addStmtToIRSB(bb, st);
      break;

    default:
      addStmtToIRSB(bb, st);
      break;
    }
  }

  tl_assert(! bus_locked);

  return bb;
}
Esempio n. 2
0
static
IRSB* ca_instrument( VgCallbackClosure * closure, 
		     IRSB* bb_in, 
		     VexGuestLayout* layout, 
                     VexGuestExtents* vge,
                     IRType gWordTy, IRType hWordTy )
{
   Int      i;
   IRSB*    bb;
   Int      count1;
   Int      count2;
   Int      count3;
   Int      count4;
   Int      count5;
   Int      count6;
   Int      count7;
   Int      count8;
   Int      count9;
   Int      sum; 
   findRepMovContext * repMovContext; 

  // do not instrument block if we have not yet read from tainted data
    if (run_prefix_task == 0)
    {

      /* Update count of BBs instrumented. Do it here to agree with */
      /* Valgrind core numbering of BBs instrumented.               */ 
      /* NOTE: our numbering of BBs executed does not agree w/core! */
      caMainBBCounter++; 
      return bb_in;
    }



   /* Counting the number of entries in a hash table */
   count1 = ca_count_hashtable(ogVarOf);
   count2 = ca_count_hashtable(ogTypeOf);
   count3 = ca_count_hashtable(cgPathCond);
   count4 = ca_count_hashtable(isIsSymbolic);
   count5 = ca_count_hashtable(caIntervalTable);
   count6 = ca_count_hashtable(cgIsDeclared);
   count7 = ca_count_hashtable(cgITEWriteStackMemSt);
   count8 = ca_count_hashtable(cgITEWriteStackMaSt);
   count9 = ca_count_hashtable(tmAddrToVar);

   // debugging option
   if (ca_output_comment) {
     VG_(printf)("XXX The number of has entries in hash tables 1-9 are %d %d %d %d %d %d %d %d %d\n",
	       count1, count2, count3, count4, count5, count6, count7, count8, count9);

     sum = count1 + count2 + count3 + count4 + count5 + count6 + count7 + count8 + count9;
     VG_(printf)("XXX The total number of hash entries in all the tables is %d\n", sum);

     VG_(printf)("XXX The size of each entry for the hash tables 1-9 are %d %d %d %d %d %d %d %d %d\n", 
	       sizeof(OgVarOfHashNode), sizeof(ogTypeOf), sizeof(cgPathCond),
	       sizeof(isIsSymbolic), sizeof(caIntervalTable), sizeof(cgIsDeclared), 
	       sizeof(cgITEWriteStackMemSt), sizeof(cgITEWriteStackMaSt), sizeof(tmAddrToVar));
   }

   if (gWordTy != hWordTy) {
	VG_(printf)("MISMATCH: "); 
	ppIRType(gWordTy);
	VG_(printf)(" "); 
	ppIRType(hWordTy);
	VG_(printf)("\n"); 
      /* We don't currently support this case. */
      VG_(tool_panic)("host/guest word size mismatch");
   }


   /* Set up BB */
   bb           = emptyIRSB();
   bb->tyenv    = deepCopyIRTypeEnv(bb_in->tyenv);
   bb->next     = deepCopyIRExpr(bb_in->next);
   bb->jumpkind = bb_in->jumpkind;

   /* Set up context for finding rep mov instructions */
   /* assume at most 400 tmp vars per basic block     */ 
   repMovContext = createRepMovContext(bb->tyenv->types_used); 


   // Copy verbatim any IR preamble preceding the first IMark
   i = 0;
   while (i < bb_in->stmts_used && bb_in->stmts[i]->tag != Ist_IMark) {
      addStmtToIRSB( bb, bb_in->stmts[i] );
      i++;
   }

     cgAddPreamble(bb,caMainBBCounter); 

   for (/*use current i*/; i < bb_in->stmts_used; i++) {
      IRStmt* st = bb_in->stmts[i];
      if (!st || st->tag == Ist_NoOp) continue;

      
      if (st->tag == Ist_Exit)
	{
	  cgAddExitPre(bb,st);
	}

      addStmtToIRSB(bb, st );
      if (ca_type_inference)
      {
	ogIRStmt(bb, st, caMainBBCounter);
      }
      
      ufInstOgIRStmt(bb, st, caMainBBCounter); 
      findRepMovIRStmt(bb, st, repMovContext, caMainBBCounter); 
      isIRStmt(bb, st, caMainBBCounter); 
      tmIRStmt(bb, st, caMainBBCounter);
      cgIRStmt(bb, st, caMainBBCounter); 
     
      if (st->tag == Ist_Exit)
      {
	cgAddExitPost(bb,st);  
      }
      
   }


   /* Update count of BBs instrumented. Do it here to agree with */
   /* Valgrind core numbering of BBs instrumented.               */ 
   caMainBBCounter++; 

   /* Destroy the rep mov context */ 
   destroyRepMovContext(repMovContext); 

   /* Return the new bb */ 
    return bb;
}
Esempio n. 3
0
/* For tools that want to know about SP changes, this pass adds
   in the appropriate hooks.  We have to do it after the tool's
   instrumentation, so the tool doesn't have to worry about the C calls
   it adds in, and we must do it before register allocation because
   spilled temps make it much harder to work out the SP deltas.
   This it is done with Vex's "second instrumentation" pass.

   Basically, we look for GET(SP)/PUT(SP) pairs and track constant
   increments/decrements of SP between them.  (This requires tracking one or
   more "aliases", which are not exact aliases but instead are tempregs
   whose value is equal to the SP's plus or minus a known constant.)
   If all the changes to SP leading up to a PUT(SP) are by known, small
   constants, we can do a specific call to eg. new_mem_stack_4, otherwise
   we fall back to the case that handles an unknown SP change.
*/
static
IRSB* vg_SP_update_pass ( void*             closureV,
                          IRSB*             sb_in, 
                          VexGuestLayout*   layout, 
                          VexGuestExtents*  vge,
                          IRType            gWordTy, 
                          IRType            hWordTy )
{
   Int         i, j, minoff_ST, maxoff_ST, sizeof_SP, offset_SP;
   IRDirty     *dcall, *d;
   IRStmt*     st;
   IRExpr*     e;
   IRRegArray* descr;
   IRType      typeof_SP;
   Long        delta, con;

   /* Set up BB */
   IRSB* bb     = emptyIRSB();
   bb->tyenv    = deepCopyIRTypeEnv(sb_in->tyenv);
   bb->next     = deepCopyIRExpr(sb_in->next);
   bb->jumpkind = sb_in->jumpkind;

   delta = 0;

   sizeof_SP = layout->sizeof_SP;
   offset_SP = layout->offset_SP;
   typeof_SP = sizeof_SP==4 ? Ity_I32 : Ity_I64;
   vg_assert(sizeof_SP == 4 || sizeof_SP == 8);

#  define IS_ADD(op) (sizeof_SP==4 ? ((op)==Iop_Add32) : ((op)==Iop_Add64))
#  define IS_SUB(op) (sizeof_SP==4 ? ((op)==Iop_Sub32) : ((op)==Iop_Sub64))

#  define IS_ADD_OR_SUB(op) (IS_ADD(op) || IS_SUB(op))

#  define GET_CONST(con)                                                \
       (sizeof_SP==4 ? (Long)(Int)(con->Ico.U32)                        \
                     : (Long)(con->Ico.U64))

// XXX: convert this to a function
#  define DO(kind, syze, tmpp)                                          \
      do {                                                              \
         if (!VG_(tdict).track_##kind##_mem_stack_##syze)               \
            goto generic;                                               \
                                                                        \
         /* I don't know if it's really necessary to say that the */    \
         /* call reads the stack pointer.  But anyway, we do. */        \
         dcall = unsafeIRDirty_0_N(                                     \
                    1/*regparms*/,                                      \
                    "track_" #kind "_mem_stack_" #syze,                 \
                    VG_(fnptr_to_fnentry)(                              \
                       VG_(tdict).track_##kind##_mem_stack_##syze ),    \
                    mkIRExprVec_1(IRExpr_RdTmp(tmpp))                   \
                 );                                                     \
         dcall->nFxState = 1;                                           \
         dcall->fxState[0].fx     = Ifx_Read;                           \
         dcall->fxState[0].offset = layout->offset_SP;                  \
         dcall->fxState[0].size   = layout->sizeof_SP;                  \
                                                                        \
         addStmtToIRSB( bb, IRStmt_Dirty(dcall) );                      \
                                                                        \
         update_SP_aliases(-delta);                                     \
                                                                        \
         n_SP_updates_fast++;                                           \
                                                                        \
      } while (0)

   clear_SP_aliases();

   for (i = 0; i <  sb_in->stmts_used; i++) {

      st = sb_in->stmts[i];

      /* t = Get(sp):   curr = t, delta = 0 */
      if (st->tag != Ist_WrTmp) goto case2;
      e = st->Ist.WrTmp.data;
      if (e->tag != Iex_Get)              goto case2;
      if (e->Iex.Get.offset != offset_SP) goto case2;
      if (e->Iex.Get.ty != typeof_SP)     goto case2;
      add_SP_alias(st->Ist.WrTmp.tmp, 0);
      addStmtToIRSB( bb, st );
      continue;

     case2:
      /* t' = curr +/- const:   curr = t',  delta +=/-= const */
      if (st->tag != Ist_WrTmp) goto case3;
      e = st->Ist.WrTmp.data;
      if (e->tag != Iex_Binop) goto case3;
      if (e->Iex.Binop.arg1->tag != Iex_RdTmp) goto case3;
      if (!get_SP_delta(e->Iex.Binop.arg1->Iex.RdTmp.tmp, &delta)) goto case3;
      if (e->Iex.Binop.arg2->tag != Iex_Const) goto case3;
      if (!IS_ADD_OR_SUB(e->Iex.Binop.op)) goto case3;
      con = GET_CONST(e->Iex.Binop.arg2->Iex.Const.con);
      if (IS_ADD(e->Iex.Binop.op)) {
         add_SP_alias(st->Ist.WrTmp.tmp, delta + con);
      } else {
         add_SP_alias(st->Ist.WrTmp.tmp, delta - con);
      }
      addStmtToIRSB( bb, st );
      continue;

     case3:
      /* t' = curr:   curr = t' */
      if (st->tag != Ist_WrTmp) goto case4;
      e = st->Ist.WrTmp.data;
      if (e->tag != Iex_RdTmp) goto case4;
      if (!get_SP_delta(e->Iex.RdTmp.tmp, &delta)) goto case4;
      add_SP_alias(st->Ist.WrTmp.tmp, delta);
      addStmtToIRSB( bb, st );
      continue;

     case4:
      /* Put(sp) = curr */
      if (st->tag != Ist_Put) goto case5;
      if (st->Ist.Put.offset != offset_SP) goto case5;
      if (st->Ist.Put.data->tag != Iex_RdTmp) goto case5;
      if (get_SP_delta(st->Ist.Put.data->Iex.RdTmp.tmp, &delta)) {
         IRTemp tttmp = st->Ist.Put.data->Iex.RdTmp.tmp;
         switch (delta) {
            case    0:                      addStmtToIRSB(bb,st); continue;
            case    4: DO(die,  4,  tttmp); addStmtToIRSB(bb,st); continue;
            case   -4: DO(new,  4,  tttmp); addStmtToIRSB(bb,st); continue;
            case    8: DO(die,  8,  tttmp); addStmtToIRSB(bb,st); continue;
            case   -8: DO(new,  8,  tttmp); addStmtToIRSB(bb,st); continue;
            case   12: DO(die,  12, tttmp); addStmtToIRSB(bb,st); continue;
            case  -12: DO(new,  12, tttmp); addStmtToIRSB(bb,st); continue;
            case   16: DO(die,  16, tttmp); addStmtToIRSB(bb,st); continue;
            case  -16: DO(new,  16, tttmp); addStmtToIRSB(bb,st); continue;
            case   32: DO(die,  32, tttmp); addStmtToIRSB(bb,st); continue;
            case  -32: DO(new,  32, tttmp); addStmtToIRSB(bb,st); continue;
            case  112: DO(die, 112, tttmp); addStmtToIRSB(bb,st); continue;
            case -112: DO(new, 112, tttmp); addStmtToIRSB(bb,st); continue;
            case  128: DO(die, 128, tttmp); addStmtToIRSB(bb,st); continue;
            case -128: DO(new, 128, tttmp); addStmtToIRSB(bb,st); continue;
            case  144: DO(die, 144, tttmp); addStmtToIRSB(bb,st); continue;
            case -144: DO(new, 144, tttmp); addStmtToIRSB(bb,st); continue;
            case  160: DO(die, 160, tttmp); addStmtToIRSB(bb,st); continue;
            case -160: DO(new, 160, tttmp); addStmtToIRSB(bb,st); continue;
            default:  
               /* common values for ppc64: 144 128 160 112 176 */
               n_SP_updates_generic_known++;
               goto generic;
         }
      } else {
Esempio n. 4
0
IRSB* DRD_(instrument)(VgCallbackClosure* const closure,
                       IRSB* const bb_in,
                       VexGuestLayout* const layout,
                       VexGuestExtents* const vge, 
                       IRType const gWordTy,
                       IRType const hWordTy)
{
   IRDirty* di;
   Int      i;
   IRSB*    bb;
   IRExpr** argv;
   Bool     instrument = True;

   /* Set up BB */
   bb           = emptyIRSB();
   bb->tyenv    = deepCopyIRTypeEnv(bb_in->tyenv);
   bb->next     = deepCopyIRExpr(bb_in->next);
   bb->jumpkind = bb_in->jumpkind;

   for (i = 0; i < bb_in->stmts_used; i++)
   {
      IRStmt* const st = bb_in->stmts[i];
      tl_assert(st);
      if (st->tag == Ist_NoOp)
         continue;

      switch (st->tag)
      {
         /* Note: the code for not instrumenting the code in .plt          */
         /* sections is only necessary on CentOS 3.0 x86 (kernel 2.4.21    */
         /* + glibc 2.3.2 + NPTL 0.60 + binutils 2.14.90.0.4).             */
         /* This is because on this platform dynamic library symbols are   */
         /* relocated in another way than by later binutils versions. The  */
         /* linker e.g. does not generate .got.plt sections on CentOS 3.0. */
      case Ist_IMark:
         instrument = VG_(seginfo_sect_kind)(NULL, 0, st->Ist.IMark.addr)
            != Vg_SectPLT;
         addStmtToIRSB(bb, st);
         break;

      case Ist_MBE:
         switch (st->Ist.MBE.event)
         {
         case Imbe_Fence:
            break; /* not interesting */
         default:
            tl_assert(0);
         }
         addStmtToIRSB(bb, st);
         break;

      case Ist_Store:
         if (instrument && /* ignore stores resulting from st{d,w}cx. */
                           st->Ist.Store.resSC == IRTemp_INVALID)
         {
            instrument_store(bb,
                             st->Ist.Store.addr,
                             sizeofIRType(typeOfIRExpr(bb->tyenv,
                                                       st->Ist.Store.data)));
         }
         addStmtToIRSB(bb, st);
         break;

      case Ist_WrTmp:
         if (instrument)
         {
            const IRExpr* const data = st->Ist.WrTmp.data;
            if (data->tag == Iex_Load)
            {
               instrument_load(bb,
                               data->Iex.Load.addr,
                               sizeofIRType(data->Iex.Load.ty));
            }
         }
         addStmtToIRSB(bb, st);
         break;

      case Ist_Dirty:
         if (instrument)
         {
            IRDirty* d = st->Ist.Dirty.details;
            IREffect const mFx = d->mFx;
            switch (mFx) {
            case Ifx_None:
               break;
            case Ifx_Read:
            case Ifx_Write:
            case Ifx_Modify:
               tl_assert(d->mAddr);
               tl_assert(d->mSize > 0);
               argv = mkIRExprVec_2(d->mAddr, mkIRExpr_HWord(d->mSize));
               if (mFx == Ifx_Read || mFx == Ifx_Modify) {
                  di = unsafeIRDirty_0_N(
                          /*regparms*/2,
                          "drd_trace_load",
                          VG_(fnptr_to_fnentry)(DRD_(trace_load)),
                          argv);
                  addStmtToIRSB(bb, IRStmt_Dirty(di));
               }
               if (mFx == Ifx_Write || mFx == Ifx_Modify)
               {
                  di = unsafeIRDirty_0_N(
                          /*regparms*/2,
                          "drd_trace_store",
                          VG_(fnptr_to_fnentry)(DRD_(trace_store)),
                          argv);
                  addStmtToIRSB(bb, IRStmt_Dirty(di));
               }
               break;
            default:
               tl_assert(0);
            }
         }
         addStmtToIRSB(bb, st);
         break;

      case Ist_CAS:
         if (instrument)
         {
            /*
             * Treat compare-and-swap as a read. By handling atomic
             * instructions as read instructions no data races are reported
             * between conflicting atomic operations nor between atomic
             * operations and non-atomic reads. Conflicts between atomic
             * operations and non-atomic write operations are still reported
             * however.
             */
            Int    dataSize;
            IRCAS* cas = st->Ist.CAS.details;
            tl_assert(cas->addr != NULL);
            tl_assert(cas->dataLo != NULL);
            dataSize = sizeofIRType(typeOfIRExpr(bb->tyenv, cas->dataLo));
            if (cas->dataHi != NULL)
               dataSize *= 2; /* since it's a doubleword-CAS */
            instrument_load(bb, cas->addr, dataSize);
         }
         addStmtToIRSB(bb, st);
         break;

      default:
         addStmtToIRSB(bb, st);
         break;
      }
   }

   return bb;
}
Esempio n. 5
0
static
IRSB* drd_instrument(VgCallbackClosure* const closure,
                     IRSB* const bb_in,
                     VexGuestLayout* const layout,
                     VexGuestExtents* const vge,
                     IRType const gWordTy,
                     IRType const hWordTy)
{
    IRDirty* di;
    Int      i;
    IRSB*    bb;
    IRExpr** argv;
    Bool     instrument = True;
    Bool     bus_locked = False;

    /* Set up BB */
    bb           = emptyIRSB();
    bb->tyenv    = deepCopyIRTypeEnv(bb_in->tyenv);
    bb->next     = deepCopyIRExpr(bb_in->next);
    bb->jumpkind = bb_in->jumpkind;

    for (i = 0; i < bb_in->stmts_used; i++)
    {
        IRStmt* const st = bb_in->stmts[i];
        tl_assert(st);
        if (st->tag == Ist_NoOp)
            continue;

        switch (st->tag)
        {
        case Ist_MBE:
            switch (st->Ist.MBE.event)
            {
            case Imbe_Fence:
                break; /* not interesting */
            case Imbe_BusLock:
                tl_assert(! bus_locked);
                bus_locked = True;
                break;
            case Imbe_BusUnlock:
                tl_assert(bus_locked);
                bus_locked = False;
                break;
            default:
                tl_assert(0);
            }
            addStmtToIRSB(bb, st);
            break;

        case Ist_Store:
            if (instrument && ! bus_locked)
            {
                instrument_store(bb,
                                 st->Ist.Store.addr,
                                 sizeofIRType(typeOfIRExpr(bb->tyenv,
                                              st->Ist.Store.data)));
            }
            addStmtToIRSB(bb, st);
            break;

        case Ist_WrTmp:
            if (instrument)
            {
                const IRExpr* const data = st->Ist.WrTmp.data;
                if (data->tag == Iex_Load)
                {
                    instrument_load(bb,
                                    data->Iex.Load.addr,
                                    sizeofIRType(data->Iex.Load.ty));
                }
            }
            addStmtToIRSB(bb, st);
            break;

        case Ist_Dirty:
            if (instrument)
            {
                IRDirty* d = st->Ist.Dirty.details;
                IREffect const mFx = d->mFx;
                switch (mFx) {
                case Ifx_None:
                    break;
                case Ifx_Read:
                case Ifx_Write:
                case Ifx_Modify:
                    tl_assert(d->mAddr);
                    tl_assert(d->mSize > 0);
                    argv = mkIRExprVec_2(d->mAddr, mkIRExpr_HWord(d->mSize));
                    if (mFx == Ifx_Read || mFx == Ifx_Modify) {
                        di = unsafeIRDirty_0_N(
                                 /*regparms*/2,
                                 "drd_trace_load",
                                 VG_(fnptr_to_fnentry)(drd_trace_load),
                                 argv);
                        addStmtToIRSB(bb, IRStmt_Dirty(di));
                    }
                    if ((mFx == Ifx_Write || mFx == Ifx_Modify)
                            && ! bus_locked)
                    {
                        di = unsafeIRDirty_0_N(
                                 /*regparms*/2,
                                 "drd_trace_store",
                                 VG_(fnptr_to_fnentry)(drd_trace_store),
                                 argv);
                        addStmtToIRSB(bb, IRStmt_Dirty(di));
                    }
                    break;
                default:
                    tl_assert(0);
                }
            }
            addStmtToIRSB(bb, st);
            break;

        default:
            addStmtToIRSB(bb, st);
            break;
        }
    }

    tl_assert(! bus_locked);

    return bb;
}