erts: Refactor out func_info into struct

This commit adds two new structs to be used to represent
erlang code in erts.

ErtsCodeInfo is used to describe the i_func_info header
that is part of all Export entries and the prelude of
each function. This replaces all the BeamInstr * that
were previously used to point to these locations.
After this change the code should never use BeamInstr *
with offsets to figure out different parts of the
func_info header.

ErtsCodeMFA is a struct that is used to descripe a
MFA in code. It is used within ErtsCodeInfo and also
in Process->current.

All function that previously took Eterm * or BeamInstr *
to identify a MFA now use the ErtsCodeMFA or ErtsCodeInfo
where appropriate.

The code has been tested to work when adding a new field to the
ErtsCodeInfo struct, but some updates are needed in ops.tab to
make it work.

1 files changed, 6 insertions, 9 deletions

diff --git a/erts/emulator/beam/erl_process.h b/erts/emulator/beam/erl_process.h
index 3347a7a60e..b266d32e76 100644
--- a/erts/emulator/beam/erl_process.h
+++ b/erts/emulator/beam/erl_process.h
@@ -93,10 +93,6 @@ struct ErtsNodesMonitor_;
 #define ERTS_HEAP_FREE(Type, Ptr, Size)					\
      erts_free((Type), (Ptr))
 
-#define INITIAL_MOD 0
-#define INITIAL_FUN 1
-#define INITIAL_ARI 2
-
 #include "export.h"
 
 struct saved_calls {
@@ -1022,15 +1018,16 @@ struct process {
 #endif
     union {
 	void *terminate;
-	BeamInstr initial[3];	/* Initial module(0), function(1), arity(2), often used instead
-				   of pointer to funcinfo instruction, hence the BeamInstr datatype */
+	ErtsCodeMFA initial;	/* Initial module(0), function(1), arity(2),
+                                   often used instead of pointer to funcinfo
+                                   instruction. */
     } u;
-    BeamInstr* current;		/* Current Erlang function, part of the funcinfo:
+    ErtsCodeMFA* current;	/* Current Erlang function, part of the funcinfo:
 				 * module(0), function(1), arity(2)
 				 * (module and functions are tagged atoms;
-				 * arity an untagged integer). BeamInstr * because it references code
+				 * arity an untagged integer).
 				 */
-    
+
     /*
      * Information mainly for post-mortem use (erl crash dump).
      */