Fit all heap data into the 32-bit address range

This is the first step in the implementation of the half-word emulator,
a 64-bit emulator where all pointers to heap data will be stored
in 32-bit words. Code specific for this emulator variant is
conditionally compiled when the HALFWORD_HEAP define has
a non-zero value.

First force all pointers to heap data to fall into a single 32-bit range,
but still store them in 64-bit words.

Temporary term data stored on C stack is moved into scheduler specific
storage (allocated as heaps) and macros are added to make this
happen only in emulators where this is needed. For a vanilla VM the
temporary terms are still stored on the C stack.

1 files changed, 3 insertions, 1 deletions

diff --git a/erts/emulator/beam/erl_bif_port.c b/erts/emulator/beam/erl_bif_port.c
index f454f2e12d..f9d97ee1ab 100644
--- a/erts/emulator/beam/erl_bif_port.c
+++ b/erts/emulator/beam/erl_bif_port.c
@@ -716,15 +716,17 @@ open_port(Process* p, Eterm name, Eterm settings, int *err_nump)
 		    }
 		} else if (option == am_cd) {
 		    Eterm iolist;
-		    Eterm heap[4];
+		    DeclareTmpHeap(heap,4,p);
 		    int r;
 
+		    UseTmpHeap(4,p);
 		    heap[0] = *tp;
 		    heap[1] = make_list(heap+2);
 		    heap[2] = make_small(0);
 		    heap[3] = NIL;
 		    iolist = make_list(heap);
 		    r = io_list_to_buf(iolist, (char*) dir, MAXPATHLEN);
+		    UnUseTmpHeap(4,p);
 		    if (r < 0) {
 			goto badarg;
 		    }