1 files changed, 43 insertions, 0 deletions
diff --git a/vendor/github.com/blevesearch/bleve/numeric/bin.go b/vendor/github.com/blevesearch/bleve/numeric/bin.go
new file mode 100644
index 0000000000..cd71392dc3
--- /dev/null
+++ b/vendor/github.com/blevesearch/bleve/numeric/bin.go
@@ -0,0 +1,43 @@
+package numeric
+
+var interleaveMagic = []uint64{
+	0x5555555555555555,
+	0x3333333333333333,
+	0x0F0F0F0F0F0F0F0F,
+	0x00FF00FF00FF00FF,
+	0x0000FFFF0000FFFF,
+	0x00000000FFFFFFFF,
+	0xAAAAAAAAAAAAAAAA,
+}
+
+var interleaveShift = []uint{1, 2, 4, 8, 16}
+
+// Interleave the first 32 bits of each uint64
+// apdated from org.apache.lucene.util.BitUtil
+// whcih was adapted from:
+// http://graphics.stanford.edu/~seander/bithacks.html#InterleaveBMN
+func Interleave(v1, v2 uint64) uint64 {
+	v1 = (v1 | (v1 << interleaveShift[4])) & interleaveMagic[4]
+	v1 = (v1 | (v1 << interleaveShift[3])) & interleaveMagic[3]
+	v1 = (v1 | (v1 << interleaveShift[2])) & interleaveMagic[2]
+	v1 = (v1 | (v1 << interleaveShift[1])) & interleaveMagic[1]
+	v1 = (v1 | (v1 << interleaveShift[0])) & interleaveMagic[0]
+	v2 = (v2 | (v2 << interleaveShift[4])) & interleaveMagic[4]
+	v2 = (v2 | (v2 << interleaveShift[3])) & interleaveMagic[3]
+	v2 = (v2 | (v2 << interleaveShift[2])) & interleaveMagic[2]
+	v2 = (v2 | (v2 << interleaveShift[1])) & interleaveMagic[1]
+	v2 = (v2 | (v2 << interleaveShift[0])) & interleaveMagic[0]
+	return (v2 << 1) | v1
+}
+
+// Deinterleave the 32-bit value starting at position 0
+// to get the other 32-bit value, shift it by 1 first
+func Deinterleave(b uint64) uint64 {
+	b &= interleaveMagic[0]
+	b = (b ^ (b >> interleaveShift[0])) & interleaveMagic[1]
+	b = (b ^ (b >> interleaveShift[1])) & interleaveMagic[2]
+	b = (b ^ (b >> interleaveShift[2])) & interleaveMagic[3]
+	b = (b ^ (b >> interleaveShift[3])) & interleaveMagic[4]
+	b = (b ^ (b >> interleaveShift[4])) & interleaveMagic[5]
+	return b
+}