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.

1 files changed, 8 insertions, 18 deletions

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);
 }