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-rw-r--r--web/server/h2o/libh2o/deps/klib/kbit.h30
1 files changed, 30 insertions, 0 deletions
diff --git a/web/server/h2o/libh2o/deps/klib/kbit.h b/web/server/h2o/libh2o/deps/klib/kbit.h
new file mode 100644
index 00000000..3793cf83
--- /dev/null
+++ b/web/server/h2o/libh2o/deps/klib/kbit.h
@@ -0,0 +1,30 @@
+#ifndef KBIT_H
+#define KBIT_H
+
+#include <stdint.h>
+
+static inline uint64_t kbi_popcount64(uint64_t y) // standard popcount; from wikipedia
+{
+ y -= ((y >> 1) & 0x5555555555555555ull);
+ y = (y & 0x3333333333333333ull) + (y >> 2 & 0x3333333333333333ull);
+ return ((y + (y >> 4)) & 0xf0f0f0f0f0f0f0full) * 0x101010101010101ull >> 56;
+}
+
+static inline uint64_t kbi_DNAcount64(uint64_t y, int c) // count #A/C/G/T from a 2-bit encoded integer; from BWA
+{
+ // reduce nucleotide counting to bits counting
+ y = ((c&2)? y : ~y) >> 1 & ((c&1)? y : ~y) & 0x5555555555555555ull;
+ // count the number of 1s in y
+ y = (y & 0x3333333333333333ull) + (y >> 2 & 0x3333333333333333ull);
+ return ((y + (y >> 4)) & 0xf0f0f0f0f0f0f0full) * 0x101010101010101ull >> 56;
+}
+
+#ifndef kroundup32 // round a 32-bit integer to the next closet integer; from "bit twiddling hacks"
+#define kroundup32(x) (--(x), (x)|=(x)>>1, (x)|=(x)>>2, (x)|=(x)>>4, (x)|=(x)>>8, (x)|=(x)>>16, ++(x))
+#endif
+
+#ifndef kbi_swap
+#define kbi_swap(a, b) (((a) ^= (b)), ((b) ^= (a)), ((a) ^= (b))) // from "bit twiddling hacks"
+#endif
+
+#endif