util: Add missing no_os_find_last_set_bit_u64 function

Add the missing 64-bit version of no_os_find_last_set_bit to provide
complete coverage for bit manipulation operations.

Signed-off-by: Antoniu Miclaus <[email protected]>

Author: amiclaus

include/no_os_util.h

@@ -137,6 +137,7 @@ uint32_t no_os_find_first_set_bit(uint32_t word);
 uint64_t no_os_find_first_set_bit_u64(uint64_t word);
 /* Find last set bit in word. */
 uint32_t no_os_find_last_set_bit(uint32_t word);
+uint64_t no_os_find_last_set_bit_u64(uint64_t word);
 /* Locate the closest element in an array. */
 uint32_t no_os_find_closest(int32_t val,
 			    const int32_t *array,

util/no_os_util.c

@@ -89,6 +89,24 @@ uint32_t no_os_find_last_set_bit(uint32_t word)
 	return last_set_bit;
 }
 
+/**
+ * Find last set bit in word.
+ */
+uint64_t no_os_find_last_set_bit_u64(uint64_t word)
+{
+	uint64_t bit = 0;
+	uint64_t last_set_bit = 64;
+
+	while (word) {
+		if (word & 0x1)
+			last_set_bit = bit;
+		word >>= 1;
+		bit ++;
+	}
+
+	return last_set_bit;
+}
+
 /**
  * Locate the closest element in an array.
  */