diff --git a/src/compress/bzip2/bit_reader.go b/src/compress/bzip2/bit_reader.go
index 32d1036ae1b..ab1d6065143 100644
--- a/src/compress/bzip2/bit_reader.go
+++ b/src/compress/bzip2/bit_reader.go
@@ -77,14 +77,6 @@ func (br *bitReader) ReadBit() bool {
 	return n != 0
 }
 
-func (br *bitReader) TryReadBit() (bit byte, ok bool) {
-	if br.bits > 0 {
-		br.bits--
-		return byte(br.n>>br.bits) & 1, true
-	}
-	return 0, false
-}
-
 func (br *bitReader) Err() error {
 	return br.err
 }
diff --git a/src/compress/bzip2/bzip2_test.go b/src/compress/bzip2/bzip2_test.go
index 77c50dfe948..c315e70b9c3 100644
--- a/src/compress/bzip2/bzip2_test.go
+++ b/src/compress/bzip2/bzip2_test.go
@@ -173,6 +173,7 @@ const rand3Hex = "1744b384d68c042371244e13500d4bfb98c6244e3d71a5b700224420b59c59
 const (
 	digits = iota
 	twain
+	random
 )
 
 var testfiles = []string{
@@ -182,6 +183,8 @@ var testfiles = []string{
 	digits: "testdata/e.txt.bz2",
 	// Twain is Project Gutenberg's edition of Mark Twain's classic English novel.
 	twain: "testdata/Mark.Twain-Tom.Sawyer.txt.bz2",
+	// 16KB of random data from /dev/urandom
+	random: "testdata/random.data.bz2",
 }
 
 func benchmarkDecode(b *testing.B, testfile int) {
@@ -198,6 +201,7 @@ func benchmarkDecode(b *testing.B, testfile int) {
 
 func BenchmarkDecodeDigits(b *testing.B) { benchmarkDecode(b, digits) }
 func BenchmarkDecodeTwain(b *testing.B)  { benchmarkDecode(b, twain) }
+func BenchmarkDecodeRand(b *testing.B)   { benchmarkDecode(b, random) }
 
 func TestBufferOverrun(t *testing.T) {
 	// Tests https://golang.org/issue/5747.
diff --git a/src/compress/bzip2/huffman.go b/src/compress/bzip2/huffman.go
index 75a6223d813..9d574b9bdef 100644
--- a/src/compress/bzip2/huffman.go
+++ b/src/compress/bzip2/huffman.go
@@ -38,23 +38,35 @@ func (t *huffmanTree) Decode(br *bitReader) (v uint16) {
 
 	for {
 		node := &t.nodes[nodeIndex]
-		bit, ok := br.TryReadBit()
-		if !ok && br.ReadBit() {
-			bit = 1
-		}
-		// bzip2 encodes left as a true bit.
-		if bit != 0 {
-			// left
-			if node.left == invalidNodeValue {
-				return node.leftValue
-			}
-			nodeIndex = node.left
+
+		var bit uint16
+		if br.bits > 0 {
+			// Get next bit - fast path.
+			br.bits--
+			bit = 0 - (uint16(br.n>>br.bits) & 1)
 		} else {
-			// right
-			if node.right == invalidNodeValue {
-				return node.rightValue
-			}
-			nodeIndex = node.right
+			// Get next bit - slow path.
+			// Use ReadBits to retrieve a single bit
+			// from the underling io.ByteReader.
+			bit = 0 - uint16(br.ReadBits(1))
+		}
+		// now
+		// bit = 0xffff if the next bit was 1
+		// bit = 0x0000 if the next bit was 0
+
+		// 1 means left, 0 means right.
+		//
+		// if bit == 0xffff {
+		//     nodeIndex = node.left
+		// } else {
+		//     nodeIndex = node.right
+		// }
+		nodeIndex = (bit & node.left) | (^bit & node.right)
+
+		if nodeIndex == invalidNodeValue {
+			// We found a leaf. Use the value of bit to decide
+			// whether is a left or a right value.
+			return (bit & node.leftValue) | (^bit & node.rightValue)
 		}
 	}
 }
diff --git a/src/compress/bzip2/testdata/random.data.bz2 b/src/compress/bzip2/testdata/random.data.bz2
new file mode 100644
index 00000000000..1ef23001668
Binary files /dev/null and b/src/compress/bzip2/testdata/random.data.bz2 differ