From: Nathael Pajani <nathael.pajani@ed3l.fr>
Date: Thu, 21 Sep 2023 22:41:36 +0000 (+0200)
Subject: Add msb() and lsb() utility functions
X-Git-Url: http://git.techno-innov.fr/?a=commitdiff_plain;h=b6571003e22e68010978f33c8c35e0d687a88cf8;p=soft%2Flpc122x%2Fcore

Add msb() and lsb() utility functions
---

diff --git a/include/lib/utils.h b/include/lib/utils.h
index bb2f761..f337216 100644
--- a/include/lib/utils.h
+++ b/include/lib/utils.h
@@ -44,11 +44,24 @@
  */
 uint8_t clz(uint32_t x);
 
+/* Return the number of the highest '1' bit in a value
+ * Will return 255 when there's no bit set.
+ */
+static inline uint8_t msb(uint32_t x)
+{
+	return (31 - clz(x));
+}
+
 /* Count traling zeroes
  * The following function is an effitient way to implement __builtin_ctz().
  */
 uint8_t ctz(uint32_t x);
 
+/* Return the number of the lowest '1' bit in a value
+ * Will return 32 when there's no bit set.
+ */
+//static inline uint8_t lsb(uint32_t x) __attribute__ ((alias ("ctz")));
+
 /* Count bits set
  */
 uint8_t bits_set(uint32_t x);