Index: pcpu.h
===================================================================
--- pcpu.h	(revision 261863)
+++ pcpu.h	(working copy)
@@ -70,11 +70,82 @@
 struct pcb;
 struct pcpu;
 
-register struct pcb *curpcb __asm__(__XSTRING(PCB_REG));
-register struct pcpu *pcpup __asm__(__XSTRING(PCPU_REG));
+/*
+ * Evaluates to the byte offset of the per-cpu variable name.
+ */
+#define	__pcpu_offset(name)						\
+	__offsetof(struct pcpu, name)
 
-#define	PCPU_GET(member)	(pcpup->pc_ ## member)
+/*
+ * Evaluates to the type of the per-cpu variable name.
+ */
+#define	__pcpu_type(name)						\
+	__typeof(((struct pcpu *)0)->name)
 
+#define	__PCPU_GET(name)	__extension__ ({			\
+	__pcpu_type(name) __res;					\
+									\
+	switch (sizeof(__res)) {					\
+	case 1:								\
+		__asm __volatile("ldub [%" __XSTRING(PCPU_REG) "+ %1], %0" \
+		: "=r" (__res) : "i" (__pcpu_offset(name)));		\
+		break;							\
+	case 2:								\
+		__asm __volatile("lduh [%" __XSTRING(PCPU_REG) "+ %1], %0"\
+		: "=r" (__res) : "i" (__pcpu_offset(name)));		\
+		break;							\
+	case 4:								\
+		__asm __volatile("ld [%" __XSTRING(PCPU_REG) "+ %1], %0"\
+		: "=r" (__res) : "i" (__pcpu_offset(name)));		\
+		break;							\
+	case 8:								\
+		__asm __volatile("ldd [%" __XSTRING(PCPU_REG) "+ %1], %0"\
+		: "=r" (__res) : "i" (__pcpu_offset(name)));		\
+		break;							\
+	default:							\
+		/* XXX - what to put here? */;				\
+	}								\
+	__res;								\
+	})
+
+#define	__PCPU_SET(name, val)	__extension__ ({			\
+	__pcpu_type(name) __val;					\
+									\
+	__val = (val);							\
+	switch (sizeof(__val)) {					\
+	case 1:								\
+		__asm __volatile("stub %0, [%" __XSTRING(PCPU_REG) "+ %1]" \
+		: : "r" (__val), "i" (__pcpu_offset(name)));		\
+		break;							\
+	case 2:								\
+		__asm __volatile("stuh %0, [%" __XSTRING(PCPU_REG) "+ %1]"\
+		: : "r" (__val), "i" (__pcpu_offset(name)));		\
+		break;							\
+	case 4:								\
+		__asm __volatile("st %0, [%" __XSTRING(PCPU_REG) "+ %1]"\
+		: : "r" (__val), "i" (__pcpu_offset(name)));		\
+		break;							\
+	case 8:								\
+		__asm __volatile("std %0, [%" __XSTRING(PCPU_REG) "+ %1]"\
+		: : "r" (__val), "i" (__pcpu_offset(name)));		\
+		break;							\
+	default:							\
+		/* XXX - what to put here? */;				\
+	}								\
+	__val;								\
+	})
+
+#define	__PCPU_PTR(name) __extension__	({				\
+	__pcpu_type(name) *__p;						\
+	struct pcpu *__pcpu;						\
+									\
+	__asm __volatile("mov %" __XSTRING(PCPU_REG) ", %0"		\
+	    : "=r" (__pcpu));						\
+	__p = &__pcpu->name;						\
+									\
+	__p;								\
+})
+
 static __inline __pure2 struct thread *
 __curthread(void)
 {
@@ -89,10 +160,11 @@
  * XXX The implementation of this operation should be made atomic
  * with respect to preemption.
  */
-#define	PCPU_ADD(member, value)	(pcpup->pc_ ## member += (value))
+#define	PCPU_GET(member)	__PCPU_GET(pc_ ## member)
+#define	PCPU_ADD(member, value)	PCPU_SET(member, PCPU_GET(member) + (value))
 #define	PCPU_INC(member)	PCPU_ADD(member, 1)
-#define	PCPU_PTR(member)	(&pcpup->pc_ ## member)
-#define	PCPU_SET(member,value)	(pcpup->pc_ ## member = (value))
+#define	PCPU_PTR(member)	__PCPU_PTR(pc_ ## member)
+#define	PCPU_SET(member,value)	__PCPU_SET(pc_ ## member, (value))
 
 #endif	/* _KERNEL */