Simplify xenomai_count_leading_zeros

Covers now all standard integer types,
no need for corner cases.
Signed-off-by: Norbert Lange <norbert.lange@andritz.com>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>

include/boilerplate/compiler.h

@@ -72,8 +72,6 @@
 extern "C" {
 #endif
 
-void __invalid_operand_size(void);
-
 #define xenomai_count_trailing_zeros(x)					\
 	((x) == 0 ? (int)(sizeof(x) * __CHAR_BIT__)			\
 	: sizeof(x) <= sizeof(unsigned int) ?				\
@@ -82,24 +80,14 @@ void __invalid_operand_size(void);
 		__builtin_ctzl((unsigned long)x)			\
 	: __builtin_ctzll(x))
 
-#define xenomai_count_leading_zeros(__v)				\
-	({								\
-		int __ret;						\
-		if (!__v)						\
-			__ret = sizeof(__v) * 8;			\
-		else							\
-			switch (sizeof(__v)) {				\
-			case sizeof(int):				\
-				__ret = __builtin_clz((unsigned int)__v); \
-				break;					\
-			case sizeof(long long):				\
-				__ret = __builtin_clzll(__v);		\
-				break;					\
-			default:					\
-				__invalid_operand_size();		\
-			}						\
-		__ret;							\
-	})
+#define xenomai_count_leading_zeros(x)					\
+	((x) == 0 ? (int)(sizeof(x) * __CHAR_BIT__)			\
+	: sizeof(x) <= sizeof(unsigned int) ?				\
+		__builtin_clz((unsigned int)x) +			\
+			(int)(sizeof(unsigned int) - sizeof(x))		\
+	: sizeof(x) <= sizeof(unsigned long) ?				\
+		__builtin_clzl((unsigned long)x)			\
+	: __builtin_clzll(x))
 
 #ifdef __cplusplus
 }