X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fruntime%2Fruntime.h;h=91e205c12044340bfe93e4d40cbe3565f8b64888;hb=c3699db2053ff3b5ac6a98d4431c3789496002d8;hp=f054a3d71af78c464244e851fce16b8e13e8fbf7;hpb=a530bbe337109d898d5b4a001fc8f1afa3b5dc39;p=sbcl.git

diff --git a/src/runtime/runtime.h b/src/runtime/runtime.h
index f054a3d..91e205c 100644
--- a/src/runtime/runtime.h
+++ b/src/runtime/runtime.h
@@ -9,10 +9,6 @@
  * files for more information.
  */
 
-/*
- * $Header$
- */
-
 /* FIXME: Aren't symbols with underscore prefixes supposed to be
  * reserved for system libraries? Perhaps rename stuff like this
  * to names like INCLUDED_SBCL_RUNTIME_H. */
@@ -34,51 +30,70 @@
  * signal handling.)
  *
  * Note: It may be that doing this is fundamentally unsound, since it
- * causes output from signal handlers, the i/o libraries aren't
+ * causes output from signal handlers, and the i/o libraries aren't
  * necessarily reentrant. But it can still be very convenient for
  * figuring out what's going on when you have a signal handling
  * problem.. */
 #define QSHOW_SIGNALS 0
 
-/* FIXME: There seems to be no reason that LowtagOf can't be defined
- * as a (possibly inline) function instead of a macro. It would also
- * be reasonable to rename the constants in ALL CAPS. */
-
-#define lowtag_Bits 3
-#define lowtag_Mask ((1<<lowtag_Bits)-1)
-#define LowtagOf(obj) ((obj)&lowtag_Mask)
-#define type_Bits 8
-#define type_Mask ((1<<type_Bits)-1)
-
-/* FIXME: There seems to be no reason that TypeOf, HeaderValue,
- * Pointerp, PTR, CONS, SYMBOL, and FDEFN can't be defined
- * as (possibly inline) functions instead of macros. */
+#define N_LOWTAG_BITS 3
+#define LOWTAG_MASK ((1<<N_LOWTAG_BITS)-1)
+#define N_WIDETAG_BITS 8
+#define WIDETAG_MASK ((1<<N_WIDETAG_BITS)-1)
 
-#define TypeOf(obj) ((obj)&type_Mask)
-#define HeaderValue(obj) ((unsigned long) ((obj)>>type_Bits))
+/* FIXME: Make HeaderValue, CONS, SYMBOL, and FDEFN into inline
+ * functions instead of macros. */
 
-#define Pointerp(obj) ((obj) & 0x01)
-#define PTR(obj) ((obj)&~lowtag_Mask)
+#define HeaderValue(obj) ((unsigned long) ((obj) >> N_WIDETAG_BITS))
 
-#define CONS(obj) ((struct cons *)((obj)-type_ListPointer))
-#define SYMBOL(obj) ((struct symbol *)((obj)-type_OtherPointer))
-#define FDEFN(obj) ((struct fdefn *)((obj)-type_OtherPointer))
+#define CONS(obj) ((struct cons *)((obj)-LIST_POINTER_LOWTAG))
+#define SYMBOL(obj) ((struct symbol *)((obj)-OTHER_POINTER_LOWTAG))
+#define FDEFN(obj) ((struct fdefn *)((obj)-OTHER_POINTER_LOWTAG))
 
 /* KLUDGE: These are in theory machine-dependent and OS-dependent, but
  * in practice the "foo int" definitions work for all the machines
  * that SBCL runs on as of 0.6.7. If we port to the Alpha or some
  * other non-32-bit machine we'll probably need real machine-dependent
  * and OS-dependent definitions again. */
-#if defined alpha
-/* We need definitions of u32 and s32. */
-#error Alpha code is stale.
-#else
+/* even on alpha, int happens to be 4 bytes.  long is longer. */
 typedef unsigned int u32;
 typedef signed int s32;
-#endif
+#define LOW_WORD(c) ((long)(c) & 0xFFFFFFFFL)
+/* this is an integral type the same length as a machine pointer */
+typedef unsigned long pointer_sized_uint_t ;
 
 typedef u32 lispobj;
 
+static inline int
+lowtag_of(lispobj obj) {
+    return obj & LOWTAG_MASK;
+}
+
+static inline int
+widetag_of(lispobj obj) {
+    return obj & WIDETAG_MASK;
+}
+
+/* Is the Lisp object obj something with pointer nature (as opposed to
+ * e.g. a fixnum or character or unbound marker)? */
+static inline int
+is_lisp_pointer(lispobj obj)
+{
+    return obj & 1;
+}
+
+/* Convert from a lispobj with type bits to a native (ordinary
+ * C/assembly) pointer to the beginning of the object. */
+static inline lispobj *
+native_pointer(lispobj obj)
+{
+    return (lispobj *) ((pointer_sized_uint_t) (obj & ~LOWTAG_MASK));
+}
+/* inverse operation: create a suitably tagged lispobj from a native
+ * pointer or integer.  Needs to be a macro due to the tedious C type
+ * system */
+#define make_lispobj(o,low_tag) ((lispobj)(LOW_WORD(o)|low_tag))
+
 /* FIXME: There seems to be no reason that make_fixnum and fixnum_value
  * can't be implemented as (possibly inline) functions. */
 #define make_fixnum(n) ((lispobj)((n)<<2))
@@ -87,18 +102,23 @@ typedef u32 lispobj;
 /* Too bad ANSI C doesn't define "bool" as C++ does.. */
 typedef int boolean;
 
-/* FIXME: There seems to be no reason that SymbolValue, SetSymbolValue,
- * and SymbolFunction can't be defined as (possibly inline) functions
- * instead of macros. */
-
-#define SymbolValue(sym) \
-    (((struct symbol *)((sym)-type_OtherPointer))->value)
-#define SetSymbolValue(sym,val) \
-    (((struct symbol *)((sym)-type_OtherPointer))->value = (val))
+/* FIXME: There seems to be no reason that SymbolFunction can't be
+ * defined as (possibly inline) functions instead of macros. */
 
+static inline lispobj SymbolValue(u32 sym, void *thread);
+static inline void SetSymbolValue(u32 sym, lispobj val, void *thread);
 /* This only works for static symbols. */
 /* FIXME: should be called StaticSymbolFunction, right? */
 #define SymbolFunction(sym) \
-    (((struct fdefn *)(SymbolValue(sym)-type_OtherPointer))->function)
+    (((struct fdefn *)(native_pointer(SymbolValue(sym,0))))->fun)
+
+/* KLUDGE: As far as I can tell there's no ANSI C way of saying
+ * "this function never returns". This is the way that you do it
+ * in GCC later than version 2.7 or so. If you are using some 
+ * compiler that doesn't understand this, you could could just
+ * change it to "typedef void never_returns" and nothing would
+ * break, though you might get a few more bytes of compiled code or
+ * a few more compiler warnings. -- WHN 2000-10-21 */
+typedef volatile void never_returns;
 
 #endif /* _SBCL_RUNTIME_H_ */