Store pointers to heap data in 32-bit words

Store Erlang terms in 32-bit entities on the heap, expanding the
pointers to 64-bit when needed. This works because all terms are stored
on addresses in the 32-bit address range (the 32 most significant bits
of pointers to term data are always 0).

Introduce a new datatype called UWord (along with its companion SWord),
which is an integer having the exact same size as the machine word
(a void *), but might be larger than Eterm/Uint.

Store code as machine words, as the instructions are pointers to
executable code which might reside outside the 32-bit address range.

Continuation pointers are stored on the 32-bit stack and hence must
point to addresses in the low range, which means that loaded beam code
much be placed in the low 32-bit address range (but, as said earlier,
the instructions themselves are full words).

No Erlang term data can be stored on C stacks (enforced by an
earlier commit).

This version gives a prompt, but test cases still fail (and dump core).

The loader (and emulator loop) has instruction packing disabled.

The main issues has been in rewriting loader and actual virtual
machine. Subsystems (like distribution) does not work yet.

1 files changed, 13 insertions, 13 deletions

diff --git a/erts/emulator/beam/erl_mtrace.c b/erts/emulator/beam/erl_mtrace.c
index 8b8ac2ec80..9f2aa62a9a 100644
--- a/erts/emulator/beam/erl_mtrace.c
+++ b/erts/emulator/beam/erl_mtrace.c
@@ -79,7 +79,7 @@ static erts_mtx_t mtrace_buf_mutex;
 #define UI16_SZ					(2)
 #define UI32_SZ					(4)
 #define UI64_SZ					(8)
-#ifdef ARCH_64
+#ifdef ARCH_64 /* XXX:PaN Halfword? (whole file...) */
 #  define UI_SZ					UI64_SZ
 #else
 #  define UI_SZ					UI32_SZ
@@ -188,7 +188,7 @@ check_alloc_entry(byte *sp, byte *ep,
 		  byte tag,
 		  Uint16 ct_no, int ct_no_n,
 		  Uint16 type, int type_n,
-		  Uint res, int res_n,
+		  UWord res, int res_n,
 		  Uint size, int size_n,
 		  Uint32 ti,int ti_n);
 void
@@ -196,8 +196,8 @@ check_realloc_entry(byte *sp, byte *ep,
 		    byte tag,
 		    Uint16 ct_no, int ct_no_n,
 		    Uint16 type, int type_n,
-		    Uint res, int res_n,
-		    Uint ptr, int ptr_n,
+		    UWord res, int res_n,
+		    UWord ptr, int ptr_n,
 		    Uint size, int size_n,
 		    Uint32 ti,int ti_n);
 void
@@ -205,7 +205,7 @@ check_free_entry(byte *sp, byte *ep,
 		 byte tag,
 		 Uint16 ct_no, int ct_no_n,
 		 Uint16 t_no, int t_no_n,
-		 Uint ptr, int ptr_n,
+		 UWord ptr, int ptr_n,
 		 Uint32 ti,int ti_n);
 void
 check_time_inc_entry(byte *sp, byte *ep,
@@ -785,7 +785,7 @@ write_alloc_entry(byte tag,
 			      tag,
 			      ct_no, ct_no_n,
 			      t_no, t_no_n,
-			      (Uint) res, res_n,
+			      (UWord) res, res_n,
 			      size, size_n,
 			      ti, ti_n);
 #endif
@@ -865,8 +865,8 @@ write_realloc_entry(byte tag,
 				tag,
 				ct_no, ct_no_n,
 				t_no, t_no_n,
-				(Uint) res, res_n,
-				(Uint) ptr, ptr_n,
+				(UWord) res, res_n,
+				(UWord) ptr, ptr_n,
 				size, size_n,
 				ti, ti_n);
 #endif
@@ -934,7 +934,7 @@ write_free_entry(byte tag,
 			     tag,
 			     ct_no, ct_no_n,
 			     t_no, t_no_n,
-			     (Uint) ptr, ptr_n,
+			     (UWord) ptr, ptr_n,
 			     ti, ti_n);
 #endif
 	}
@@ -1135,7 +1135,7 @@ check_alloc_entry(byte *sp, byte *ep,
 		  byte tag,
 		  Uint16 ct_no, int ct_no_n,
 		  Uint16 t_no, int t_no_n,
-		  Uint res, int res_n,
+		  UWord res, int res_n,
 		  Uint size, int size_n,
 		  Uint32 ti,int ti_n)
 {
@@ -1163,8 +1163,8 @@ check_realloc_entry(byte *sp, byte *ep,
 		    byte tag,
 		    Uint16 ct_no, int ct_no_n,
 		    Uint16 t_no, int t_no_n,
-		    Uint res, int res_n,
-		    Uint ptr, int ptr_n,
+		    UWord res, int res_n,
+		    UWord ptr, int ptr_n,
 		    Uint size, int size_n,
 		    Uint32 ti,int ti_n)
 {
@@ -1193,7 +1193,7 @@ check_free_entry(byte *sp, byte *ep,
 		 byte tag,
 		 Uint16 ct_no, int ct_no_n,
 		 Uint16 t_no, int t_no_n,
-		 Uint ptr, int ptr_n,
+		 UWord ptr, int ptr_n,
 		 Uint32 ti,int ti_n)
 {
     byte *p = sp;