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#ifndef BITOPS_H_
#define BITOPS_H_
#include "util.h"
/* Find most significant (last) bit set. */
static inline uint8_t fls16(uint16_t value)
{
uint8_t ret = 16u;
if (value == 0u)
return 0u;
if ((value & 0xFF00u) == 0u) {
value = (uint16_t)(value << 8);
ret = (uint8_t)(ret - 8u);
}
if ((value & 0xF000u) == 0u) {
value = (uint16_t)(value << 4);
ret = (uint8_t)(ret - 4u);
}
if ((value & 0xC000u) == 0u) {
value = (uint16_t)(value << 2);
ret = (uint8_t)(ret - 2u);
}
if ((value & 0x8000u) == 0u) {
value = (uint16_t)(value << 1);
ret = (uint8_t)(ret - 1u);
}
return ret;
}
/* Find most significant (last) bit set. */
static inline uint8_t fls8(uint8_t value)
{
uint8_t ret = 8u;
if (value == 0u)
return 0u;
if ((value & 0xF0u) == 0u) {
value = (uint8_t)(value << 4);
ret = (uint8_t)(ret - 4u);
}
if ((value & 0xC0u) == 0u) {
value = (uint8_t)(value << 2);
ret = (uint8_t)(ret - 2u);
}
if ((value & 0x80u) == 0u) {
value = (uint8_t)(value << 1);
ret = (uint8_t)(ret - 1u);
}
return ret;
}
#endif /* BITOPS_H_ */
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