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[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [PATCH v20210701 02/40] tools: add API to work with sevaral bits at once
Introduce new API to test if a fixed number of bits is clear or set,
and clear or set them all at once.
The caller has to make sure the input bitnumber is a multiple of BITS_PER_LONG.
This API avoids the loop over each bit in a known range just to see
if all of them are either clear or set.
Signed-off-by: Olaf Hering <olaf@xxxxxxxxx>
v02:
- change return type from int to bool (jgross)
---
tools/libs/ctrl/xc_bitops.h | 28 ++++++++++++++++++++++++++++
1 file changed, 28 insertions(+)
diff --git a/tools/libs/ctrl/xc_bitops.h b/tools/libs/ctrl/xc_bitops.h
index f0bac4a071..8e8c6efb45 100644
--- a/tools/libs/ctrl/xc_bitops.h
+++ b/tools/libs/ctrl/xc_bitops.h
@@ -3,6 +3,7 @@
/* bitmap operations for single threaded access */
+#include <stdbool.h>
#include <stdlib.h>
#include <string.h>
@@ -77,4 +78,31 @@ static inline void bitmap_or(void *_dst, const void *_other,
dst[i] |= other[i];
}
+static inline bool test_bit_long_set(unsigned long nr_base, const void *_addr)
+{
+ const unsigned long *addr = _addr;
+ unsigned long val = addr[nr_base / BITS_PER_LONG];
+
+ return val == ~0;
+}
+
+static inline bool test_bit_long_clear(unsigned long nr_base, const void
*_addr)
+{
+ const unsigned long *addr = _addr;
+ unsigned long val = addr[nr_base / BITS_PER_LONG];
+
+ return val == 0;
+}
+
+static inline void clear_bit_long(unsigned long nr_base, void *_addr)
+{
+ unsigned long *addr = _addr;
+ addr[nr_base / BITS_PER_LONG] = 0;
+}
+
+static inline void set_bit_long(unsigned long nr_base, void *_addr)
+{
+ unsigned long *addr = _addr;
+ addr[nr_base / BITS_PER_LONG] = ~0;
+}
#endif /* XC_BITOPS_H */
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