arch/x86/include/asm/percpu.h | 31 ++++++++++++++++---------------
 1 file changed, 16 insertions(+), 15 deletions(-)

diff --git a/arch/x86/include/asm/percpu.h b/arch/x86/include/asm/percpu.h
index 2278797c769d..b479a0e650e5 100644
--- a/arch/x86/include/asm/percpu.h
+++ b/arch/x86/include/asm/percpu.h
@@ -86,6 +86,17 @@
 /* For arch-specific code, we can use direct single-insn ops (they
  * don't give an lvalue though). */
 extern void __bad_percpu_size(void);
+extern void __bad_expr_size(void);
+
+#define pick_type_expression(x, e8, e16, e32, e64)	\
+	__builtin_choose_expr(sizeof(x)==1, e8,		\
+	__builtin_choose_expr(sizeof(x)==2, e16,	\
+	__builtin_choose_expr(sizeof(x)==4, e32,	\
+	__builtin_choose_expr(sizeof(x)==8, e64,	\
+	__bad_expr_size()))))
+
+#define pick_type_statement(x, s8, s16, s32, s64) \
+	pick_type_expression(x, ({s8;0;}), ({s16;0;}),({s32;0;}),({s64;0;}))
 
 #define percpu_to_op(qual, op, var, val)		\
 do {							\
@@ -95,29 +106,19 @@ do {							\
 		pto_tmp__ = (val);			\
 		(void)pto_tmp__;			\
 	}						\
-	switch (sizeof(var)) {				\
-	case 1:						\
+	pick_type_statement(var,			\
 		asm qual (op "b %1,"__percpu_arg(0)	\
 		    : "+m" (var)			\
-		    : "qi" ((pto_T__)(val)));		\
-		break;					\
-	case 2:						\
+		    : "qi" ((pto_T__)(val))),		\
 		asm qual (op "w %1,"__percpu_arg(0)	\
 		    : "+m" (var)			\
-		    : "ri" ((pto_T__)(val)));		\
-		break;					\
-	case 4:						\
+		    : "ri" ((pto_T__)(val))),		\
 		asm qual (op "l %1,"__percpu_arg(0)	\
 		    : "+m" (var)			\
-		    : "ri" ((pto_T__)(val)));		\
-		break;					\
-	case 8:						\
+		    : "ri" ((pto_T__)(val))),		\
 		asm qual (op "q %1,"__percpu_arg(0)	\
 		    : "+m" (var)			\
-		    : "re" ((pto_T__)(val)));		\
-		break;					\
-	default: __bad_percpu_size();			\
-	}						\
+		    : "re" ((pto_T__)(val))));		\
 } while (0)
 
 /*