diff --git a/sys/alpha/include/ipl.h b/sys/alpha/include/ipl.h
index 201aad06e4c..0e390666654 100644
--- a/sys/alpha/include/ipl.h
+++ b/sys/alpha/include/ipl.h
@@ -70,6 +70,12 @@ static __inline int name(void)				\
 	return s;					\
     } else						\
 	return cpl;					\
+}							\
+							\
+static __inline int					\
+is_##name(void)					\
+{							\
+    return (getcpl() >= ALPHA_PSL_IP_L##pri);		\
 }
 
 SPLUP(splsoftcam, SOFT)
diff --git a/sys/i386/isa/ipl_funcs.c b/sys/i386/isa/ipl_funcs.c
index 78b1c1d5fef..5a305ec7f1d 100644
--- a/sys/i386/isa/ipl_funcs.c
+++ b/sys/i386/isa/ipl_funcs.c
@@ -67,14 +67,19 @@ softclockpending(void)
 
 #ifndef SMP
 
-#define	GENSPL(NAME, OP, MODIFIER, PC)		\
-unsigned NAME(void)				\
-{						\
-	unsigned x;				\
-						\
-	x = cpl;				\
-	cpl OP MODIFIER;			\
-	return (x);				\
+#define	GENSPL(NAME, OP, MODIFIER, PC)			\
+unsigned NAME(void)					\
+{							\
+	unsigned x;					\
+							\
+	x = cpl;					\
+	cpl OP MODIFIER;				\
+	return (x);					\
+}							\
+int							\
+is_##NAME(void)						\
+{							\
+	return ((cpl & (MODIFIER)) == (MODIFIER));	\
 }
 
 void
@@ -186,23 +191,35 @@ unsigned NAME(void)							\
 	IFCPL_UNLOCK();							\
 									\
 	return (x);							\
+}									\
+int									\
+is_##NAME(void)								\
+{									\
+	return ((cpl & (MODIFIER)) == (MODIFIER));			\
 }
 
+
 #else /* INTR_SPL */
 
-#define	GENSPL(NAME, OP, MODIFIER, PC)		\
-unsigned NAME(void)				\
-{						\
-	unsigned x;				\
-						\
-	IFCPL_LOCK();				\
-	x = cpl;				\
-	cpl OP MODIFIER;			\
-	IFCPL_UNLOCK();				\
-						\
-	return (x);				\
+#define	GENSPL(NAME, OP, MODIFIER, PC)			\
+unsigned NAME(void)					\
+{							\
+	unsigned x;					\
+							\
+	IFCPL_LOCK();					\
+	x = cpl;					\
+	cpl OP MODIFIER;				\
+	IFCPL_UNLOCK();					\
+							\
+	return (x);					\
+}							\
+int							\
+is_##NAME(void)						\
+{							\
+	return ((cpl & (MODIFIER)) == (MODIFIER));	\
 }
 
+
 #endif /* INTR_SPL */
 
 
diff --git a/sys/sys/systm.h b/sys/sys/systm.h
index ffbd1ce0a59..f4e4d263dfc 100644
--- a/sys/sys/systm.h
+++ b/sys/sys/systm.h
@@ -44,6 +44,7 @@
 
 #include <machine/atomic.h>
 #include <machine/cpufunc.h>
+#include <machine/ipl.h>
 #include <sys/callout.h>
 
 extern int securelevel;		/* system security level (see init(8)) */
@@ -75,8 +76,13 @@ extern int bootverbose;		/* nonzero to print verbose messages */
 
 #ifdef	INVARIANTS		/* The option is always available */
 #define	KASSERT(exp,msg)	do { if (!(exp)) panic msg; } while (0)
+#define SPLSTRINGIZE(a) #a
+#define SPLASSERT(level, msg)						\
+	KASSERT(is_spl##level(), ("%s: not spl%s, cpl == 0x%08x\n",	\
+		(msg), SPLSTRINGIZE(level), cpl))					
 #else
 #define	KASSERT(exp,msg)
+#define SPLASSERT(level, msg)
 #endif
 
 /*
@@ -124,6 +130,7 @@ u_quad_t strtouq __P((const char *, char **, int));
 
 void	bcopy __P((const void *from, void *to, size_t len));
 void	ovbcopy __P((const void *from, void *to, size_t len));
+
 #ifdef __i386__
 extern void	(*bzero) __P((void *buf, size_t len));
 #else
@@ -227,6 +234,26 @@ intrmask_t	splsoftvm __P((void));
 intrmask_t	splstatclock __P((void));
 intrmask_t	spltty __P((void));
 intrmask_t	splvm __P((void));
+#if defined (INVARIANT_SUPPORT)
+/* 
+ * The Alpha has all of these as static __inline.
+ */
+int		is_splbio __P((void));
+int		is_splcam __P((void));
+int		is_splclock __P((void));
+int		is_splhigh __P((void));
+int		is_splimp __P((void));
+int		is_splnet __P((void));
+int		is_splsoftcam __P((void));
+int		is_splsoftcambio __P((void));
+int		is_splsoftcamnet __P((void));
+int		is_splsoftclock __P((void));
+int		is_splsofttty __P((void));
+int		is_splsoftvm __P((void));
+int		is_splstatclock __P((void));
+int		is_spltty __P((void));
+int		is_splvm __P((void));
+#endif /* INVARIANT_SUPPORT */
 void		splx __P((intrmask_t ipl));
 void		splz __P((void));
 #endif /* __i386__ */