Refactor macros for accessing Beam instructions

The BeamOp() macro in erl_vm.h is clumsy to use. All users
cast the return value to BeamInstr.

Define new macros that are easier to use. In the future,
we might want to pack an operand into the same word as
the pointer to the instruction, so we will define two macros.

BeamIsOpCode() is used to rewrite code like this:

  if (Instr == (BeamInstr) BeamOp(op_i_func_info_IaaI) {
    ...
  }

to:

  if (BeamIsOpCode(Instr, op_i_func_info_IaaI)) {
    ...
  }

BeamOpCodeAddr(op_apply_bif) is used when we need the address
for an instruction.

Also elimiminate the global variables em_* in beam_emu.c.
They are not really needed. Use the BeamOpCodeAddr() macro
instead.

17 files changed, 111 insertions, 133 deletions

diff --git a/erts/emulator/beam/beam_bif_load.c b/erts/emulator/beam/beam_bif_load.c
index e48415ecc4..00822d1415 100644
--- a/erts/emulator/beam/beam_bif_load.c
+++ b/erts/emulator/beam/beam_bif_load.c
@@ -823,11 +823,11 @@ BIF_RETTYPE finish_after_on_load_2(BIF_ALIST_2)
 		ep->beam[1] = 0;
 	    } else {
 		if (ep->addressv[code_ix] == ep->beam &&
-		    ep->beam[0] == (BeamInstr) em_apply_bif) {
+		    BeamIsOpCode(ep->beam[0], op_apply_bif)) {
 		    continue;
 		}
-		ep->addressv[code_ix] = ep->beam;
-		ep->beam[0] = (BeamInstr) em_call_error_handler;
+                ep->addressv[code_ix] = ep->beam;
+                ep->beam[0] = BeamOpCodeAddr(op_call_error_handler);
 	    }
 	}
 	modp->curr.code_hdr->on_load_function_ptr = NULL;
@@ -849,7 +849,7 @@ BIF_RETTYPE finish_after_on_load_2(BIF_ALIST_2)
 	    if (ep == NULL || ep->info.mfa.module != BIF_ARG_1) {
 		continue;
 	    }
-	    if (ep->beam[0] == (BeamInstr) em_apply_bif) {
+	    if (BeamIsOpCode(ep->beam[0], op_apply_bif)) {
 		continue;
 	    }
 	    ep->beam[1] = 0;
@@ -1766,22 +1766,23 @@ delete_code(Module* modp)
 	Export *ep = export_list(i, code_ix);
         if (ep != NULL && (ep->info.mfa.module == module)) {
 	    if (ep->addressv[code_ix] == ep->beam) {
-		if (ep->beam[0] == (BeamInstr) em_apply_bif) {
+		if (BeamIsOpCode(ep->beam[0], op_apply_bif)) {
 		    continue;
 		}
-		else if (ep->beam[0] ==
-			 (BeamInstr) BeamOp(op_i_generic_breakpoint)) {
+		else if (BeamIsOpCode(ep->beam[0], op_i_generic_breakpoint)) {
 		    ERTS_LC_ASSERT(erts_thr_progress_is_blocking());
 		    ASSERT(modp->curr.num_traced_exports > 0);
 		    DBG_TRACE_MFA_P(&ep->info.mfa,
 				  "export trace cleared, code_ix=%d", code_ix);
 		    erts_clear_export_break(modp, &ep->info);
 		}
-		else ASSERT(ep->beam[0] == (BeamInstr) em_call_error_handler
-			    || !erts_initialized);
-	    }
+		else {
+                    ASSERT(BeamIsOpCode(ep->beam[0], op_call_error_handler) ||
+                           !erts_initialized);
+                }
+            }
 	    ep->addressv[code_ix] = ep->beam;
-	    ep->beam[0] = (BeamInstr) em_call_error_handler;
+	    ep->beam[0] = BeamOpCodeAddr(op_call_error_handler);
 	    ep->beam[1] = 0;
 	    DBG_TRACE_MFA_P(&ep->info.mfa,
 			    "export invalidation, code_ix=%d", code_ix);
diff --git a/erts/emulator/beam/beam_bp.c b/erts/emulator/beam/beam_bp.c
index 49ec59c989..c81380c14d 100644
--- a/erts/emulator/beam/beam_bp.c
+++ b/erts/emulator/beam/beam_bp.c
@@ -203,7 +203,7 @@ erts_bp_match_functions(BpFunctions* f, ErtsCodeMFA *mfa, int specified)
 	for (fi = 0; fi < num_functions; fi++) {
 
 	    ci = code_hdr->functions[fi];
-	    ASSERT(ci->op == (BeamInstr) BeamOp(op_i_func_info_IaaI));
+	    ASSERT(BeamIsOpCode(ci->op, op_i_func_info_IaaI));
 	    if (erts_is_function_native(ci)) {
 		continue;
 	    }
@@ -265,11 +265,11 @@ erts_bp_match_export(BpFunctions* f, ErtsCodeMFA *mfa, int specified)
 
 	pc = ep->beam;
 	if (ep->addressv[code_ix] == pc) {
-	    if ((*pc == (BeamInstr) em_apply_bif ||
-		 *pc == (BeamInstr) em_call_error_handler)) {
-		continue;
+	    if (BeamIsOpCode(*pc, op_apply_bif) ||
+                BeamIsOpCode(*pc, op_call_error_handler)) {
+                continue;
 	    }
-	    ASSERT(*pc == (BeamInstr) BeamOp(op_i_generic_breakpoint));
+	    ASSERT(BeamIsOpCode(*pc, op_i_generic_breakpoint));
 	} else if (erts_is_function_native(erts_code_to_codeinfo(ep->addressv[code_ix]))) {
 	    continue;
 	}
@@ -366,8 +366,8 @@ consolidate_bp_data(Module* modp, ErtsCodeInfo *ci, int local)
 	    }
 	    ASSERT(modp->curr.num_breakpoints >= 0);
 	    ASSERT(modp->curr.num_traced_exports >= 0);
-	    ASSERT(*erts_codeinfo_to_code(ci) !=
-                   (BeamInstr) BeamOp(op_i_generic_breakpoint));
+	    ASSERT(! BeamIsOpCode(*erts_codeinfo_to_code(ci),
+                                  op_i_generic_breakpoint));
 	}
 	ci->u.gen_bp = NULL;
 	Free(g);
@@ -415,7 +415,7 @@ erts_install_breakpoints(BpFunctions* f)
 {
     Uint i;
     Uint n = f->matched;
-    BeamInstr br = (BeamInstr) BeamOp(op_i_generic_breakpoint);
+    BeamInstr br = BeamOpCodeAddr(op_i_generic_breakpoint);
 
     for (i = 0; i < n; i++) {
 	ErtsCodeInfo* ci = f->matching[i].ci;
@@ -460,7 +460,7 @@ static void
 uninstall_breakpoint(ErtsCodeInfo *ci)
 {
     BeamInstr *pc = erts_codeinfo_to_code(ci);
-    if (*pc == (BeamInstr) BeamOp(op_i_generic_breakpoint)) {
+    if (BeamIsOpCode(*pc, op_i_generic_breakpoint)) {
 	GenericBp* g = ci->u.gen_bp;
 	if (g->data[erts_active_bp_ix()].flags == 0) {
 	    /*
@@ -642,7 +642,7 @@ erts_generic_breakpoint(Process* c_p, ErtsCodeInfo *info, Eterm* reg)
     Uint bp_flags;
     ErtsBpIndex ix = erts_active_bp_ix();
 
-    ASSERT(info->op == (BeamInstr) BeamOp(op_i_func_info_IaaI));
+    ASSERT(BeamIsOpCode(info->op, op_i_func_info_IaaI));
 
     g = info->u.gen_bp;
     bp = &g->data[ix];
@@ -695,9 +695,9 @@ erts_generic_breakpoint(Process* c_p, ErtsCodeInfo *info, Eterm* reg)
 	Eterm w;
 	erts_trace_time_call(c_p, info, bp->time);
 	w = (BeamInstr) *c_p->cp;
-	if (! (w == (BeamInstr) BeamOp(op_i_return_time_trace) ||
-	       w == (BeamInstr) BeamOp(op_return_trace) ||
-	       w == (BeamInstr) BeamOp(op_i_return_to_trace)) ) {
+	if (! (BeamIsOpCode(w, op_i_return_time_trace) ||
+	       BeamIsOpCode(w, op_return_trace) ||
+               BeamIsOpCode(w, op_i_return_to_trace)) ) {
 	    Eterm* E = c_p->stop;
 	    ASSERT(c_p->htop <= E && E <= c_p->hend);
 	    if (E - 2 < c_p->htop) {
@@ -717,7 +717,7 @@ erts_generic_breakpoint(Process* c_p, ErtsCodeInfo *info, Eterm* reg)
     }
 
     if (bp_flags & ERTS_BPF_DEBUG) {
-	return (BeamInstr) BeamOp(op_i_debug_breakpoint);
+	return BeamOpCodeAddr(op_i_debug_breakpoint);
     } else {
 	return g->orig_instr;
     }
@@ -946,12 +946,12 @@ do_call_trace(Process* c_p, ErtsCodeInfo* info, Eterm* reg,
     Eterm* E = c_p->stop;
 
     w = *c_p->cp;
-    if (w == (BeamInstr) BeamOp(op_return_trace)) {
+    if (BeamIsOpCode(w, op_return_trace)) {
 	cpp = &E[2];
-    } else if (w == (BeamInstr) BeamOp(op_i_return_to_trace)) {
+    } else if (BeamIsOpCode(w, op_i_return_to_trace)) {
 	return_to_trace = 1;
 	cpp = &E[0];
-    } else if (w == (BeamInstr) BeamOp(op_i_return_time_trace)) {
+    } else if (BeamIsOpCode(w, op_i_return_time_trace)) {
 	cpp = &E[0];
     } else {
 	cpp = NULL;
@@ -959,12 +959,12 @@ do_call_trace(Process* c_p, ErtsCodeInfo* info, Eterm* reg,
     if (cpp) {
 	for (;;) {
 	    BeamInstr w = *cp_val(*cpp);
-	    if (w == (BeamInstr) BeamOp(op_return_trace)) {
+	    if (BeamIsOpCode(w, op_return_trace)) {
 		cpp += 3;
-	    } else if (w == (BeamInstr) BeamOp(op_i_return_to_trace)) {
+	    } else if (BeamIsOpCode(w, op_i_return_to_trace)) {
 		return_to_trace = 1;
 		cpp += 1;
-	    } else if (w == (BeamInstr) BeamOp(op_i_return_time_trace)) {
+            } else if (BeamIsOpCode(w, op_i_return_time_trace)) {
 		cpp += 2;
 	    } else {
 		break;
@@ -1293,7 +1293,7 @@ erts_find_local_func(ErtsCodeMFA *mfa) {
     n = (BeamInstr) code_hdr->num_functions;
     for (i = 0; i < n; ++i) {
 	ci = code_hdr->functions[i];
-	ASSERT(((BeamInstr) BeamOp(op_i_func_info_IaaI)) == ci->op);
+	ASSERT(BeamIsOpCode(ci->op, op_i_func_info_IaaI));
 	ASSERT(mfa->module == ci->mfa.module || is_nil(ci->mfa.module));
 	if (mfa->function == ci->mfa.function &&
 	    mfa->arity == ci->mfa.arity) {
@@ -1708,7 +1708,7 @@ check_break(ErtsCodeInfo *ci, Uint break_flags)
 {
     GenericBp* g = ci->u.gen_bp;
 
-    ASSERT(ci->op == (BeamInstr) BeamOp(op_i_func_info_IaaI));
+    ASSERT(BeamIsOpCode(ci->op, op_i_func_info_IaaI));
     if (erts_is_function_native(ci)) {
 	return 0;
     }
diff --git a/erts/emulator/beam/beam_debug.c b/erts/emulator/beam/beam_debug.c
index 7819e9907d..0f332da63f 100644
--- a/erts/emulator/beam/beam_debug.c
+++ b/erts/emulator/beam/beam_debug.c
@@ -199,7 +199,7 @@ void debug_dump_code(BeamInstr *I, int num)
 	erts_print(ERTS_PRINT_DSBUF, (void *) dsbufp, HEXF ": ", code_ptr);
 	instr = (BeamInstr) code_ptr[0];
 	for (i = 0; i < NUM_SPECIFIC_OPS; i++) {
-	    if (instr == (BeamInstr) BeamOp(i) && opc[i].name[0] != '\0') {
+	    if (BeamIsOpCode(instr, i) && opc[i].name[0] != '\0') {
 		code_ptr += print_op(ERTS_PRINT_DSBUF, (void *) dsbufp,
 				     i, opc[i].sz-1, code_ptr+1) + 1;
 		break;
@@ -319,7 +319,7 @@ erts_debug_disassemble_1(BIF_ALIST_1)
     erts_print(ERTS_PRINT_DSBUF, (void *) dsbufp, HEXF ": ", code_ptr);
     instr = (BeamInstr) code_ptr[0];
     for (i = 0; i < NUM_SPECIFIC_OPS; i++) {
-	if (instr == (BeamInstr) BeamOp(i) && opc[i].name[0] != '\0') {
+	if (BeamIsOpCode(instr, i) && opc[i].name[0] != '\0') {
 	    code_ptr += print_op(ERTS_PRINT_DSBUF, (void *) dsbufp,
 				 i, opc[i].sz-1, code_ptr+1) + 1;
 	    break;
diff --git a/erts/emulator/beam/beam_emu.c b/erts/emulator/beam/beam_emu.c
index c2aab32995..8d5cc76015 100644
--- a/erts/emulator/beam/beam_emu.c
+++ b/erts/emulator/beam/beam_emu.c
@@ -158,11 +158,6 @@ BeamInstr beam_apply[2];
 BeamInstr beam_exit[1];
 BeamInstr beam_continue_exit[1];
 
-BeamInstr* em_call_error_handler;
-BeamInstr* em_apply_bif;
-BeamInstr* em_call_nif;
-BeamInstr* em_call_bif_e;
-
 
 /* NOTE These should be the only variables containing trace instructions.
 **      Sometimes tests are form the instruction value, and sometimes
@@ -977,11 +972,6 @@ void process_main(Eterm * x_reg_array, FloatDef* f_reg_array)
 #endif /* ERTS_OPCODE_COUNTER_SUPPORT */
 #endif /* NO_JUMP_TABLE */
      
-     em_call_error_handler = OpCode(call_error_handler);
-     em_apply_bif = OpCode(apply_bif);
-     em_call_nif = OpCode(call_nif);
-     em_call_bif_e = OpCode(call_bif_e);
-
      beam_apply[0]             = (BeamInstr) OpCode(i_apply);
      beam_apply[1]             = (BeamInstr) OpCode(normal_exit);
      beam_exit[0]              = (BeamInstr) OpCode(error_action_code);
@@ -1002,7 +992,7 @@ void process_main(Eterm * x_reg_array, FloatDef* f_reg_array)
 	 ep->beam[0] = (BeamInstr) OpCode(apply_bif);
 	 ep->beam[1] = (BeamInstr) bif_table[i].f;
 	 /* XXX: set func info for bifs */
-	 ep->info.op = (BeamInstr) BeamOp(op_i_func_info_IaaI);
+	 ep->info.op = BeamOpCodeAddr(op_i_func_info_IaaI);
      }
 
      return;
@@ -1249,12 +1239,12 @@ void erts_dirty_process_main(ErtsSchedulerData *esdp)
 	ERTS_UNREQ_PROC_MAIN_LOCK(c_p);
 
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-	if (em_apply_bif == (BeamInstr *) *I) {
+	if (BeamIsOpCode(*I, op_apply_bif)) {
 	    exiting = erts_call_dirty_bif(esdp, c_p, I, reg);
 	}
 	else {
-	    ASSERT(em_call_nif == (BeamInstr *) *I);
-	    exiting = erts_call_dirty_nif(esdp, c_p, I, reg);
+	    ASSERT(BeamIsOpCode(*I, op_call_nif));
+            exiting = erts_call_dirty_nif(esdp, c_p, I, reg);
 	}
 
 	ASSERT(!(c_p->flags & F_HIBERNATE_SCHED));
@@ -2089,8 +2079,8 @@ apply_bif_error_adjustment(Process *p, Export *ep,
      * and apply_last_IP.
      */
     if (I
-	&& ep->beam[0] == (BeamInstr) em_apply_bif
-	&& (ep == bif_export[BIF_error_1]
+	&& BeamIsOpCode(ep->beam[0], op_apply_bif)
+        && (ep == bif_export[BIF_error_1]
 	    || ep == bif_export[BIF_error_2]
 	    || ep == bif_export[BIF_exit_1]
 	    || ep == bif_export[BIF_throw_1])) {
@@ -3196,8 +3186,8 @@ erts_is_builtin(Eterm Mod, Eterm Name, int arity)
     if ((ep = export_get(&e)) == NULL) {
 	return 0;
     }
-    return ep->addressv[erts_active_code_ix()] == ep->beam
-	&& (ep->beam[0] == (BeamInstr) em_apply_bif);
+    return ep->addressv[erts_active_code_ix()] == ep->beam &&
+	BeamIsOpCode(ep->beam[0], op_apply_bif);
 }
 
 
diff --git a/erts/emulator/beam/beam_load.c b/erts/emulator/beam/beam_load.c
index 3f9dc2c1aa..1fb284a303 100644
--- a/erts/emulator/beam/beam_load.c
+++ b/erts/emulator/beam/beam_load.c
@@ -55,12 +55,6 @@ ErlDrvBinary* erts_gzinflate_buffer(char*, int);
 #define DEFINED   1
 #define EXPORTED  2
 
-#ifdef NO_JUMP_TABLE
-#  define BeamOpCode(Op) ((BeamInstr)(Op))
-#else
-#  define BeamOpCode(Op) ((BeamInstr)beam_ops[Op])
-#endif
-
 #if defined(WORDS_BIGENDIAN)
 # define NATIVE_ENDIAN(F)			\
   if ((F).val & BSF_NATIVE) {			\
@@ -849,10 +843,9 @@ erts_finish_loading(Binary* magic, Process* c_p,
 		continue;
 	    }
 	    if (ep->addressv[code_ix] == ep->beam) {
-		if (ep->beam[0] == (BeamInstr) em_apply_bif) {
+		if (BeamIsOpCode(ep->beam[0], op_apply_bif)) {
 		    continue;
-		} else if (ep->beam[0] ==
-			   (BeamInstr) BeamOp(op_i_generic_breakpoint)) {
+		} else if (BeamIsOpCode(ep->beam[0], op_i_generic_breakpoint)) {
 		    ERTS_LC_ASSERT(erts_thr_progress_is_blocking());
 		    ASSERT(mod_tab_p->curr.num_traced_exports > 0);
 		    erts_clear_export_break(mod_tab_p, &ep->info);
@@ -1482,7 +1475,7 @@ load_import_table(LoaderState* stp)
 	 * the BIF function.
 	 */
 	if ((e = erts_active_export_entry(mod, func, arity)) != NULL) {
-	    if (e->beam[0] == (BeamInstr) em_apply_bif) {
+	    if (BeamIsOpCode(e->beam[0], op_apply_bif)) {
 		stp->import[i].bf = (BifFunction) e->beam[1];
 		if (func == am_load_nif && mod == am_erlang && arity == 2) {
 		    stp->may_load_nif = 1;
@@ -1576,7 +1569,7 @@ is_bif(Eterm mod, Eterm func, unsigned arity)
     if (e == NULL) {
 	return 0;
     }
-    if (e->beam[0] != (BeamInstr) em_apply_bif) {
+    if (! BeamIsOpCode(e->beam[0], op_apply_bif)) {
 	return 0;
     }
     if (mod == am_erlang && func == am_apply && arity == 3) {
@@ -2323,7 +2316,7 @@ load_code(LoaderState* stp)
 	    stp->specific_op = specific;
 	    CodeNeed(opc[stp->specific_op].sz+16); /* Extra margin for packing */
             last_instr_start = ci + opc[stp->specific_op].adjust;
-	    code[ci++] = BeamOpCode(stp->specific_op);
+	    code[ci++] = BeamOpCodeAddr(stp->specific_op);
 	}
 	
 	/*
@@ -5079,7 +5072,7 @@ final_touch(LoaderState* stp, struct erl_module_instance* inst_p)
     while (index != 0) {
 	BeamInstr next = codev[index];
         BeamInstr* abs_addr;
-	codev[index] = BeamOpCode(op_catch_yf);
+	codev[index] = BeamOpCodeAddr(op_catch_yf);
         /* We must make the address of the label absolute again. */
         abs_addr = (BeamInstr *)codev + index + codev[index+2];
 	catches = beam_catches_cons(abs_addr, catches);
@@ -6033,9 +6026,9 @@ int
 erts_is_function_native(ErtsCodeInfo *ci)
 {
 #ifdef HIPE
-    ASSERT(ci->op == (BeamInstr) BeamOp(op_i_func_info_IaaI));
-    return erts_codeinfo_to_code(ci)[0] == (BeamInstr) BeamOp(op_hipe_trap_call)
-	|| erts_codeinfo_to_code(ci)[0] == (BeamInstr) BeamOp(op_hipe_trap_call_closure);
+    ASSERT(BeamIsOpCode(ci->op, op_i_func_info_IaaI));
+    return BeamIsOpCode(erts_codeinfo_to_code(ci)[0], op_hipe_trap_call) ||
+	BeamIsOpCode(erts_codeinfo_to_code(ci)[0], op_hipe_trap_call_closure);
 #else
     return 0;
 #endif
@@ -6104,7 +6097,7 @@ exported_from_module(Process* p, /* Process whose heap to use. */
 	    Eterm tuple;
 	    
 	    if (ep->addressv[code_ix] == ep->beam &&
-		ep->beam[0] == (BeamInstr) em_call_error_handler) {
+		BeamIsOpCode(ep->beam[0], op_call_error_handler)) {
 		/* There is a call to the function, but it does not exist. */ 
 		continue;
 	    }
@@ -6375,7 +6368,7 @@ make_stub(ErtsCodeInfo* info, Eterm mod, Eterm func, Uint arity, Uint native, Be
 {
     DBG_TRACE_MFA(mod,func,arity,"make beam stub at %p", erts_codeinfo_to_code(info));
     ASSERT(WORDS_PER_FUNCTION == 6);
-    info->op = (BeamInstr) BeamOp(op_i_func_info_IaaI);
+    info->op = BeamOpCodeAddr(op_i_func_info_IaaI);
     info->u.ncallee = (void (*)(void)) native;
     info->mfa.module = mod;
     info->mfa.function = func;
@@ -6480,7 +6473,7 @@ stub_final_touch(LoaderState* stp, ErtsCodeInfo* ci)
     for (i = 0, lp = stp->lambdas; i < n; i++, lp++) {
         ErlFunEntry* fe = stp->lambdas[i].fe;
 	if (lp->function == ci->mfa.function && lp->arity == ci->mfa.arity) {
-	    *erts_codeinfo_to_code(ci) = (Eterm) BeamOpCode(op_hipe_trap_call_closure);
+	    *erts_codeinfo_to_code(ci) = BeamOpCodeAddr(op_hipe_trap_call_closure);
             fe->address = erts_codeinfo_to_code(ci);
 	}
     }
@@ -6804,7 +6797,7 @@ erts_make_stub_module(Process* p, Eterm hipe_magic_bin, Eterm Beam, Eterm Info)
 	 * as the body until we know what kind of trap we should put there.
 	 */
 	code_hdr->functions[i] = (ErtsCodeInfo*)fp;
-	op = (Eterm) BeamOpCode(op_hipe_trap_call); /* Might be changed later. */
+	op = BeamOpCodeAddr(op_hipe_trap_call); /* Might be changed later. */
 	fp = make_stub((ErtsCodeInfo*)fp, hipe_stp->module, func, arity,
                        (Uint)native_address, op);
     }
@@ -6814,7 +6807,7 @@ erts_make_stub_module(Process* p, Eterm hipe_magic_bin, Eterm Beam, Eterm Info)
      */
 
     code_hdr->functions[i] = (ErtsCodeInfo*)fp;
-    *fp++ = (BeamInstr) BeamOp(op_int_code_end);
+    *fp++ = BeamOpCodeAddr(op_int_code_end);
 
     /*
      * Copy attributes and compilation information.
diff --git a/erts/emulator/beam/beam_load.h b/erts/emulator/beam/beam_load.h
index c4a90d3f3a..156c3c45e2 100644
--- a/erts/emulator/beam/beam_load.h
+++ b/erts/emulator/beam/beam_load.h
@@ -37,11 +37,6 @@ typedef struct gen_op_entry {
 
 extern const GenOpEntry gen_opc[];
 
-extern BeamInstr beam_debug_apply[];
-extern BeamInstr* em_call_error_handler;
-extern BeamInstr* em_apply_bif;
-extern BeamInstr* em_call_nif;
-
 struct ErtsLiteralArea_;
 
 /*
diff --git a/erts/emulator/beam/bif.c b/erts/emulator/beam/bif.c
index 80f391e91e..ad555bb195 100644
--- a/erts/emulator/beam/bif.c
+++ b/erts/emulator/beam/bif.c
@@ -5031,7 +5031,7 @@ void erts_init_trap_export(Export* ep, Eterm m, Eterm f, Uint a,
     ep->info.mfa.module = m;
     ep->info.mfa.function = f;
     ep->info.mfa.arity = a;
-    ep->beam[0] = (BeamInstr) em_apply_bif;
+    ep->beam[0] = BeamOpCodeAddr(op_apply_bif);
     ep->beam[1] = (BeamInstr) bif;
 }
 
@@ -5096,7 +5096,7 @@ schedule(Process *c_p, Process *dirty_shadow_proc,
 {
     ERTS_LC_ASSERT(ERTS_PROC_LOCK_MAIN & erts_proc_lc_my_proc_locks(c_p));
     (void) erts_nif_export_schedule(c_p, dirty_shadow_proc,
-				    mfa, pc, (BeamInstr) em_apply_bif,
+				    mfa, pc, BeamOpCodeAddr(op_apply_bif),
 				    dfunc, ifunc,
 				    module, function,
 				    argc, argv);
@@ -5145,7 +5145,6 @@ static BIF_RETTYPE dirty_bif_exception(BIF_ALIST_2)
 }
 
 
-extern BeamInstr* em_call_bif_e;
 static BIF_RETTYPE call_bif(Process *c_p, Eterm *reg, BeamInstr *I);
 
 BIF_RETTYPE
@@ -5218,13 +5217,13 @@ erts_schedule_bif(Process *proc,
 	    mfa = &exp->info.mfa;
 	}
 #endif
-	else if (em_call_bif_e == (BeamInstr *) *i) {
+	else if (BeamIsOpCode(*i, op_call_bif_e)) {
 	    /* Pointer to bif export in i+1 */
 	    exp = (Export *) i[1];
 	    pc = i;
 	    mfa = &exp->info.mfa;
 	}
-	else if (em_apply_bif == (BeamInstr *) *i) {
+	else if (BeamIsOpCode(*i, op_apply_bif)) {
 	    /* Pointer to bif in i+1, and mfa in i-3 */	    
 	    pc = c_p->cp;
 	    mfa = erts_code_to_codemfa(i);
diff --git a/erts/emulator/beam/code_ix.h b/erts/emulator/beam/code_ix.h
index 9e3280cd98..42976d2301 100644
--- a/erts/emulator/beam/code_ix.h
+++ b/erts/emulator/beam/code_ix.h
@@ -176,7 +176,7 @@ int erts_has_code_write_permission(void);
 ERTS_GLB_INLINE
 BeamInstr *erts_codeinfo_to_code(ErtsCodeInfo *ci)
 {
-    ASSERT(ci->op == (BeamInstr) BeamOp(op_i_func_info_IaaI) || !ci->op);
+    ASSERT(BeamIsOpCode(ci->op, op_i_func_info_IaaI) || !ci->op);
     ASSERT_MFA(&ci->mfa);
     return (BeamInstr*)(ci + 1);
 }
@@ -185,7 +185,7 @@ ERTS_GLB_INLINE
 ErtsCodeInfo *erts_code_to_codeinfo(BeamInstr *I)
 {
     ErtsCodeInfo *ci = ((ErtsCodeInfo *)(((char *)(I)) - sizeof(ErtsCodeInfo)));
-    ASSERT(ci->op == (BeamInstr) BeamOp(op_i_func_info_IaaI) || !ci->op);
+    ASSERT(BeamIsOpCode(ci->op, op_i_func_info_IaaI) || !ci->op);
     ASSERT_MFA(&ci->mfa);
     return ci;
 }
diff --git a/erts/emulator/beam/erl_bif_trace.c b/erts/emulator/beam/erl_bif_trace.c
index 3fe089a00e..22942b40c4 100644
--- a/erts/emulator/beam/erl_bif_trace.c
+++ b/erts/emulator/beam/erl_bif_trace.c
@@ -966,12 +966,12 @@ static int function_is_traced(Process *p,
     if ((ep = export_get(&e)) != NULL) {
 	pc = ep->beam;
 	if (ep->addressv[erts_active_code_ix()] == pc &&
-	    *pc != (BeamInstr) em_call_error_handler) {
+	    ! BeamIsOpCode(*pc, op_call_error_handler)) {
 
 	    int r = 0;
 
-	    ASSERT(*pc == (BeamInstr) em_apply_bif ||
-		   *pc == (BeamInstr) BeamOp(op_i_generic_breakpoint));
+	    ASSERT(BeamIsOpCode(*pc, op_apply_bif) ||
+		   BeamIsOpCode(*pc, op_i_generic_breakpoint));
 
 	    if (erts_is_trace_break(&ep->info, ms, 0)) {
 		return FUNC_TRACE_GLOBAL_TRACE;
@@ -1361,14 +1361,14 @@ erts_set_trace_pattern(Process*p, ErtsCodeMFA *mfa, int specified,
 	    if (ep->addressv[code_ix] != pc) {
 		fp[i].mod->curr.num_traced_exports++;
 #ifdef DEBUG
-		ep->info.op = (BeamInstr) BeamOp(op_i_func_info_IaaI);
+		ep->info.op = BeamOpCodeAddr(op_i_func_info_IaaI);
 #endif
-                ep->beam[0] = (BeamInstr) BeamOp(op_trace_jump_W);
+                ep->beam[0] = BeamOpCodeAddr(op_trace_jump_W);
 		ep->beam[1] = (BeamInstr) ep->addressv[code_ix];
 	    }
 	    erts_set_call_trace_bif(ci, match_prog_set, 0);
 	    if (ep->addressv[code_ix] != pc) {
-		ep->beam[0] = (BeamInstr) BeamOp(op_i_generic_breakpoint);
+		ep->beam[0] = BeamOpCodeAddr(op_i_generic_breakpoint);
 	    }
 	} else if (!on && flags.breakpoint) {
 	    /* Turn off breakpoint tracing -- nothing to do here. */
@@ -1378,8 +1378,8 @@ erts_set_trace_pattern(Process*p, ErtsCodeMFA *mfa, int specified,
 	     * before turning on breakpoint tracing.
 	     */
 	    erts_clear_call_trace_bif(ci, 0);
-	    if (ep->beam[0] == (BeamInstr) BeamOp(op_i_generic_breakpoint)) {
-		ep->beam[0] = (BeamInstr) BeamOp(op_trace_jump_W);
+	    if (BeamIsOpCode(ep->beam[0], op_i_generic_breakpoint)) {
+		ep->beam[0] = BeamOpCodeAddr(op_trace_jump_W);
 	    }
 	}
     }
@@ -1671,7 +1671,7 @@ uninstall_exp_breakpoints(BpFunctions* f)
 	if (ep->addressv[code_ix] != ep->beam) {
 	    continue;
 	}
-	ASSERT(ep->beam[0] == (BeamInstr) BeamOp(op_trace_jump_W));
+	ASSERT(BeamIsOpCode(ep->beam[0], op_trace_jump_W));
 	ep->addressv[code_ix] = (BeamInstr *) ep->beam[1];
     }
 }
@@ -1690,7 +1690,7 @@ clean_export_entries(BpFunctions* f)
 	if (ep->addressv[code_ix] == ep->beam) {
 	    continue;
 	}
-	if (ep->beam[0] == (BeamInstr) BeamOp(op_trace_jump_W)) {
+	if (BeamIsOpCode(ep->beam[0], op_trace_jump_W)) {
 	    ep->beam[0] = (BeamInstr) 0;
 	    ep->beam[1] = (BeamInstr) 0;
 	}
diff --git a/erts/emulator/beam/erl_nfunc_sched.h b/erts/emulator/beam/erl_nfunc_sched.h
index 9be0e6f7c7..b8a4e4ebc3 100644
--- a/erts/emulator/beam/erl_nfunc_sched.h
+++ b/erts/emulator/beam/erl_nfunc_sched.h
@@ -211,8 +211,8 @@ erts_proc_shadow2real(Process *c_p)
 #define ERTS_NFUNC_SCHED_INTERNALS__
 
 #define ERTS_I_BEAM_OP_TO_NIF_EXPORT(I)					\
-    (ASSERT(BeamOp(op_apply_bif) == (BeamInstr *) (*(I))		\
-	    || BeamOp(op_call_nif) == (BeamInstr *) (*(I))),		\
+    (ASSERT(BeamIsOpCode(*(I), op_apply_bif) ||                         \
+            BeamIsOpCode(*(I), op_call_nif)),                           \
      ((NifExport *) (((char *) (I)) - offsetof(NifExport, exp.beam[0]))))
 
 
diff --git a/erts/emulator/beam/erl_nif.c b/erts/emulator/beam/erl_nif.c
index 43441e0228..f7f12efe28 100644
--- a/erts/emulator/beam/erl_nif.c
+++ b/erts/emulator/beam/erl_nif.c
@@ -292,7 +292,7 @@ schedule(ErlNifEnv* env, NativeFunPtr direct_fp, NativeFunPtr indirect_fp,
     ep = erts_nif_export_schedule(c_p, dirty_shadow_proc,
 				  c_p->current,
 				  c_p->cp,
-				  (BeamInstr) em_call_nif,
+				  BeamOpCodeAddr(op_call_nif),
 				  direct_fp, indirect_fp,
 				  mod, func_name,
 				  argc, (const Eterm *) argv);
@@ -3613,7 +3613,7 @@ static ErtsCodeInfo** get_func_pp(BeamCodeHeader* mod_code, Eterm f_atom, unsign
     int j;
     for (j = 0; j < n; ++j) {
 	ErtsCodeInfo* ci = mod_code->functions[j];
-	ASSERT(ci->op == (BeamInstr) BeamOp(op_i_func_info_IaaI));
+	ASSERT(BeamIsOpCode(ci->op, op_i_func_info_IaaI));
 	if (f_atom == ci->mfa.function
 	    && arity == ci->mfa.arity) {
 	    return mod_code->functions+j;
@@ -3982,13 +3982,12 @@ BIF_RETTYPE load_nif_2(BIF_ALIST_2)
             code_ptr = erts_codeinfo_to_code(ci);
 
 	    if (ci->u.gen_bp == NULL) {
-		code_ptr[0] = (BeamInstr) BeamOp(op_call_nif);
+		code_ptr[0] = BeamOpCodeAddr(op_call_nif);
 	    }
 	    else { /* Function traced, patch the original instruction word */
 		GenericBp* g = ci->u.gen_bp;
-		ASSERT(code_ptr[0] ==
-		       (BeamInstr) BeamOp(op_i_generic_breakpoint));
-		g->orig_instr = (BeamInstr) BeamOp(op_call_nif);
+		ASSERT(BeamIsOpCode(code_ptr[0], op_i_generic_breakpoint));
+		g->orig_instr = BeamOpCodeAddr(op_call_nif);
 	    }
 	    if (f->flags) {
 		code_ptr[3] = (BeamInstr) f->fptr;
diff --git a/erts/emulator/beam/erl_vm.h b/erts/emulator/beam/erl_vm.h
index 076767c7cd..0e32559f1b 100644
--- a/erts/emulator/beam/erl_vm.h
+++ b/erts/emulator/beam/erl_vm.h
@@ -202,11 +202,15 @@ extern int erts_pd_initial_size;/* Initial Process dictionary table size */
 
 #include "erl_term.h"
 
-#ifdef NO_JUMP_TABLE 
-#define BeamOp(Op) (Op)
+#if defined(NO_JUMP_TABLE)
+#  define BeamOpsAreInitialized() (1)
+#  define BeamOpCodeAddr(OpCode) ((BeamInstr)(OpCode))
 #else
 extern void** beam_ops;
-#define BeamOp(Op) beam_ops[(Op)]
+#  define BeamOpsAreInitialized() (beam_ops != 0)
+#  define BeamOpCodeAddr(OpCode) ((BeamInstr)beam_ops[(OpCode)])
 #endif
 
+#define BeamIsOpCode(InstrWord, OpCode) ((InstrWord) == BeamOpCodeAddr(OpCode))
+
 #endif	/* __ERL_VM_H__ */
diff --git a/erts/emulator/beam/export.c b/erts/emulator/beam/export.c
index c81503f722..946ffeffb8 100644
--- a/erts/emulator/beam/export.c
+++ b/erts/emulator/beam/export.c
@@ -48,7 +48,6 @@ static erts_atomic_t total_entries_bytes;
  */
 erts_mtx_t export_staging_lock;
 
-extern BeamInstr* em_call_error_handler;
 extern BeamInstr* em_call_traced_function;
 
 struct export_entry
@@ -130,7 +129,10 @@ export_alloc(struct export_entry* tmpl_e)
 	obj->info.mfa.module = tmpl->info.mfa.module;
 	obj->info.mfa.function = tmpl->info.mfa.function;
 	obj->info.mfa.arity = tmpl->info.mfa.arity;
-	obj->beam[0] = (BeamInstr) em_call_error_handler;
+        obj->beam[0] = 0;
+        if (BeamOpsAreInitialized()) {
+            obj->beam[0] = BeamOpCodeAddr(op_call_error_handler);
+        }
 	obj->beam[1] = 0;
 
 	for (ix=0; ix<ERTS_NUM_CODE_IX; ix++) {
@@ -267,7 +269,7 @@ erts_find_function(Eterm m, Eterm f, unsigned int a, ErtsCodeIndex code_ix)
     ee = hash_get(&export_tables[code_ix].htable, init_template(&templ, m, f, a));
     if (ee == NULL ||
 	(ee->ep->addressv[code_ix] == ee->ep->beam &&
-	 ee->ep->beam[0] != (BeamInstr) BeamOp(op_i_generic_breakpoint))) {
+	 ! BeamIsOpCode(ee->ep->beam[0], op_i_generic_breakpoint))) {
 	return NULL;
     }
     return ee->ep;
diff --git a/erts/emulator/beam/export.h b/erts/emulator/beam/export.h
index be6cce07bf..194e514b12 100644
--- a/erts/emulator/beam/export.h
+++ b/erts/emulator/beam/export.h
@@ -73,7 +73,7 @@ extern erts_mtx_t export_staging_lock;
 #include "beam_load.h" /* For em_* extern declarations */ 
 #define ExportIsBuiltIn(EntryPtr) 			\
 (((EntryPtr)->addressv[erts_active_code_ix()] == (EntryPtr)->beam) && \
- ((EntryPtr)->beam[0] == (BeamInstr) em_apply_bif))
+ (BeamIsOpCode((EntryPtr)->beam[0], op_apply_bif)))
 
 #if ERTS_GLB_INLINE_INCL_FUNC_DEF
 
diff --git a/erts/emulator/hipe/hipe_bif0.c b/erts/emulator/hipe/hipe_bif0.c
index 05663648e9..380031bf13 100644
--- a/erts/emulator/hipe/hipe_bif0.c
+++ b/erts/emulator/hipe/hipe_bif0.c
@@ -53,8 +53,6 @@
 #include "hipe_literals.h"
 #endif
 
-#define BeamOpCode(Op)	((Uint)BeamOp(Op))
-
 
 int term_to_Sint32(Eterm term, Sint *sp)
 {
@@ -615,7 +613,7 @@ static ErtsCodeInfo* hipe_find_emu_address(Eterm mod, Eterm name, unsigned int a
     n = code_hdr->num_functions;
     for (i = 0; i < n; ++i) {
 	ErtsCodeInfo *ci = code_hdr->functions[i];
-	ASSERT(ci->op == BeamOpCode(op_i_func_info_IaaI));
+	ASSERT(BeamIsOpCode(ci->op, op_i_func_info_IaaI));
 	if (ci->mfa.function == name && ci->mfa.arity == arity)
 	    return ci;
     }
diff --git a/erts/emulator/hipe/hipe_bif1.c b/erts/emulator/hipe/hipe_bif1.c
index 3d3df4fd48..73d07f0ce5 100644
--- a/erts/emulator/hipe/hipe_bif1.c
+++ b/erts/emulator/hipe/hipe_bif1.c
@@ -32,11 +32,10 @@
 #include "big.h"
 #include "error.h"
 #include "beam_load.h"
+#include "erl_vm.h"
 #include "hipe_bif0.h"
 #include "hipe_bif1.h"
 
-#define BeamOpCode(Op)	((Uint)BeamOp(Op))
-
 BIF_RETTYPE hipe_bifs_call_count_on_1(BIF_ALIST_1)
 {
     ErtsCodeInfo *ci;
@@ -46,17 +45,17 @@ BIF_RETTYPE hipe_bifs_call_count_on_1(BIF_ALIST_1)
     ci = hipe_bifs_find_pc_from_mfa(BIF_ARG_1);
     if (!ci)
 	BIF_ERROR(BIF_P, BADARG);
-    ASSERT(ci->op == BeamOpCode(op_i_func_info_IaaI));
+    ASSERT(BeamIsOpCode(ci->op, op_i_func_info_IaaI));
     pc = erts_codeinfo_to_code(ci);
-    if (pc[0] == BeamOpCode(op_hipe_trap_call))
+    if (BeamIsOpCode(pc[0], op_hipe_trap_call))
 	BIF_ERROR(BIF_P, BADARG);
-    if (pc[0] == BeamOpCode(op_hipe_call_count))
+    if (BeamIsOpCode(pc[0], op_hipe_call_count))
 	BIF_RET(NIL);
     hcc = erts_alloc(ERTS_ALC_T_HIPE_SL, sizeof(*hcc));
     hcc->count = 0;
     hcc->opcode = pc[0];
     ci->u.hcc = hcc;
-    pc[0] = BeamOpCode(op_hipe_call_count);
+    pc[0] = BeamOpCodeAddr(op_hipe_call_count);
     BIF_RET(am_true);
 }
 
@@ -70,9 +69,9 @@ BIF_RETTYPE hipe_bifs_call_count_off_1(BIF_ALIST_1)
     ci = hipe_bifs_find_pc_from_mfa(BIF_ARG_1);
     if (!ci)
 	BIF_ERROR(BIF_P, BADARG);
-    ASSERT(ci->op == BeamOpCode(op_i_func_info_IaaI));
+    ASSERT(BeamIsOpCode(ci->op, op_i_func_info_IaaI));
     pc = erts_codeinfo_to_code(ci);
-    if (pc[0] != BeamOpCode(op_hipe_call_count))
+    if (! BeamIsOpCode(pc[0], op_hipe_call_count))
 	BIF_RET(am_false);
     hcc = ci->u.hcc;
     count = hcc->count;
@@ -91,9 +90,9 @@ BIF_RETTYPE hipe_bifs_call_count_get_1(BIF_ALIST_1)
     ci = hipe_bifs_find_pc_from_mfa(BIF_ARG_1);
     if (!ci)
 	BIF_ERROR(BIF_P, BADARG);
-    ASSERT(ci->op == BeamOpCode(op_i_func_info_IaaI));
+    ASSERT(BeamIsOpCode(ci->op, op_i_func_info_IaaI));
     pc = erts_codeinfo_to_code(ci);
-    if (pc[0] != BeamOpCode(op_hipe_call_count))
+    if (! BeamIsOpCode(pc[0], op_hipe_call_count))
 	BIF_RET(am_false);
     hcc = ci->u.hcc;
     BIF_RET(make_small(hcc->count));
@@ -109,9 +108,9 @@ BIF_RETTYPE hipe_bifs_call_count_clear_1(BIF_ALIST_1)
     ci = hipe_bifs_find_pc_from_mfa(BIF_ARG_1);
     if (!ci)
 	BIF_ERROR(BIF_P, BADARG);
-    ASSERT(ci->op == BeamOpCode(op_i_func_info_IaaI));
+    ASSERT(BeamIsOpCode(ci->op, op_i_func_info_IaaI));
     pc = erts_codeinfo_to_code(ci);
-    if (pc[0] != BeamOpCode(op_hipe_call_count))
+    if (! BeamIsOpCode(pc[0], op_hipe_call_count))
 	BIF_RET(am_false);
     hcc = ci->u.hcc;
     count = hcc->count;
diff --git a/erts/emulator/hipe/hipe_mode_switch.c b/erts/emulator/hipe/hipe_mode_switch.c
index b7f81fc4a6..8b497c9970 100644
--- a/erts/emulator/hipe/hipe_mode_switch.c
+++ b/erts/emulator/hipe/hipe_mode_switch.c
@@ -155,8 +155,6 @@ void hipe_check_pcb(Process *p, const char *file, unsigned line)
 #include "hipe_arm_glue.h"
 #endif
 
-#define BeamOpCode(Op)		((Uint)BeamOp(Op))
-
 Uint hipe_beam_pc_return[1];	/* needed in hipe_debug.c */
 Uint hipe_beam_pc_throw[1];	/* needed in hipe_debug.c */
 Uint hipe_beam_pc_resume[1];	/* needed by hipe_set_timeout() */
@@ -166,9 +164,9 @@ void hipe_mode_switch_init(void)
 {
     hipe_arch_glue_init();
 
-    hipe_beam_pc_return[0] = BeamOpCode(op_hipe_trap_return);
-    hipe_beam_pc_throw[0] = BeamOpCode(op_hipe_trap_throw);
-    hipe_beam_pc_resume[0] = BeamOpCode(op_hipe_trap_resume);
+    hipe_beam_pc_return[0] = BeamOpCodeAddr(op_hipe_trap_return);
+    hipe_beam_pc_throw[0] = BeamOpCodeAddr(op_hipe_trap_throw);
+    hipe_beam_pc_resume[0] = BeamOpCodeAddr(op_hipe_trap_resume);
 
     hipe_beam_catch_throw =
 	make_catch(beam_catches_cons(hipe_beam_pc_throw, BEAM_CATCHES_NIL));
@@ -182,8 +180,8 @@ void hipe_set_call_trap(ErtsCodeInfo* ci, void *nfun, int is_closure)
     HIPE_ASSERT(ci->op == BeamOpCode(op_i_func_info_IaaI));
     bfun[0] =
 	is_closure
-	? BeamOpCode(op_hipe_trap_call_closure)
-	: BeamOpCode(op_hipe_trap_call);
+	? BeamOpCodeAddr(op_hipe_trap_call_closure)
+	: BeamOpCodeAddr(op_hipe_trap_call);
     ci->u.ncallee = (void (*)(void)) nfun;
 }