Fix definition of `stack-top-address' to make it consistent with

definition of `object-datum' (which will be used to extract the
address value of a stack address).  Implement new primitive
`stack-address-offset' which computes the offset (in objects) between
the stack-address argument and the top of stack.

diff --git a/v7/src/microcode/comutl.c b/v7/src/microcode/comutl.c
index f412f32b009ed25fb6b2e708d7b26af80d2b9ca2..f4c59522d7dc6b0981882c143d4af387f622beaf 100644 (file)
--- a/v7/src/microcode/comutl.c
+++ b/v7/src/microcode/comutl.c
@@ -1,6 +1,6 @@
 /* -*-C-*-
 
-$Header: /Users/cph/tmp/foo/mit-scheme/mit-scheme/v7/src/microcode/comutl.c,v 1.15 1988/12/23 04:32:24 cph Exp $
+$Header: /Users/cph/tmp/foo/mit-scheme/mit-scheme/v7/src/microcode/comutl.c,v 1.16 1988/12/23 04:50:23 cph Exp $
 
 Copyright (c) 1987, 1988 Massachusetts Institute of Technology
 
@@ -77,7 +77,7 @@ DEFINE_PRIMITIVE ("STACK-TOP-ADDRESS", Prim_stack_top_address, 0, 0, 0)
 {
   PRIMITIVE_HEADER (0);
 
-  PRIMITIVE_RETURN (C_Integer_To_Scheme_Integer (OBJECT_DATUM (Stack_Top)));
+  PRIMITIVE_RETURN (C_Integer_To_Scheme_Integer ((long) (Stack_Top)));
 }
 
 #define STACK_ADDRESS_P(object)                                                \
@@ -91,7 +91,7 @@ DEFINE_PRIMITIVE ("STACK-ADDRESS-OFFSET", Prim_stack_address_offset, 1, 1, 0)
   PRIMITIVE_RETURN
     (C_Integer_To_Scheme_Integer
      ((STACK_LOCATIVE_DIFFERENCE
-       ((OBJECT_DATUM (ARG_REF (1))), (OBJECT_DATUM (Stack_Top))))
+       ((OBJECT_DATUM (ARG_REF (1))), ((long) (Stack_Top))))
       / (sizeof (Pointer))));
 }