X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fruntime%2Fruntime.h;h=f204cf157a247ee405183ee96c3236c1a17e590a;hb=bc46c8bcdd6ac8918df8ea9e9db49808e4924fcf;hp=f054a3d71af78c464244e851fce16b8e13e8fbf7;hpb=a530bbe337109d898d5b4a001fc8f1afa3b5dc39;p=sbcl.git

diff --git a/src/runtime/runtime.h b/src/runtime/runtime.h
index f054a3d..f204cf1 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 +30,68 @@
  * 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 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 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: Make HeaderValue, CONS, SYMBOL, and FDEFN into inline
+ * functions instead of macros. */
 
-/* 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 HeaderValue(obj) ((unsigned long) ((obj) >> N_WIDETAG_BITS))
 
-#define TypeOf(obj) ((obj)&type_Mask)
-#define HeaderValue(obj) ((unsigned long) ((obj)>>type_Bits))
-
-#define Pointerp(obj) ((obj) & 0x01)
-#define PTR(obj) ((obj)&~lowtag_Mask)
-
-#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.
+#if ((defined alpha) && !(defined __linux__))
+#error No u32,s32 definitions for this platform.  Write some.
 #else
+/* int happens to be 4 bytes on linux/alpha.  long is longer. */
 typedef unsigned int u32;
 typedef signed int s32;
+#define LOW_WORD(c) ((long)(c) & 0xFFFFFFFFL)
 #endif
 
 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 obj & ~LOWTAG_MASK;
+}
+
 /* 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))
@@ -92,13 +105,22 @@ typedef int boolean;
  * instead of macros. */
 
 #define SymbolValue(sym) \
-    (((struct symbol *)((sym)-type_OtherPointer))->value)
+    (((struct symbol *)((sym)-OTHER_POINTER_LOWTAG))->value)
 #define SetSymbolValue(sym,val) \
-    (((struct symbol *)((sym)-type_OtherPointer))->value = (val))
+    (((struct symbol *)((sym)-OTHER_POINTER_LOWTAG))->value = (val))
 
 /* This only works for static symbols. */
 /* FIXME: should be called StaticSymbolFunction, right? */
 #define SymbolFunction(sym) \
-    (((struct fdefn *)(SymbolValue(sym)-type_OtherPointer))->function)
+    (((struct fdefn *)(SymbolValue(sym)-OTHER_POINTER_LOWTAG))->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_ */