diff options
Diffstat (limited to 'vendor/github.com/klauspost/compress/flate/huffman_bit_writer.go')
-rw-r--r-- | vendor/github.com/klauspost/compress/flate/huffman_bit_writer.go | 39 |
1 files changed, 19 insertions, 20 deletions
diff --git a/vendor/github.com/klauspost/compress/flate/huffman_bit_writer.go b/vendor/github.com/klauspost/compress/flate/huffman_bit_writer.go index 208d66711..db54be139 100644 --- a/vendor/github.com/klauspost/compress/flate/huffman_bit_writer.go +++ b/vendor/github.com/klauspost/compress/flate/huffman_bit_writer.go @@ -5,6 +5,7 @@ package flate import ( + "encoding/binary" "io" ) @@ -206,7 +207,7 @@ func (w *huffmanBitWriter) write(b []byte) { } func (w *huffmanBitWriter) writeBits(b int32, nb uint16) { - w.bits |= uint64(b) << (w.nbits & reg16SizeMask64) + w.bits |= uint64(b) << w.nbits w.nbits += nb if w.nbits >= 48 { w.writeOutBits() @@ -420,13 +421,11 @@ func (w *huffmanBitWriter) writeOutBits() { w.bits >>= 48 w.nbits -= 48 n := w.nbytes - w.bytes[n] = byte(bits) - w.bytes[n+1] = byte(bits >> 8) - w.bytes[n+2] = byte(bits >> 16) - w.bytes[n+3] = byte(bits >> 24) - w.bytes[n+4] = byte(bits >> 32) - w.bytes[n+5] = byte(bits >> 40) + + // We over-write, but faster... + binary.LittleEndian.PutUint64(w.bytes[n:], bits) n += 6 + if n >= bufferFlushSize { if w.err != nil { n = 0 @@ -435,6 +434,7 @@ func (w *huffmanBitWriter) writeOutBits() { w.write(w.bytes[:n]) n = 0 } + w.nbytes = n } @@ -759,7 +759,7 @@ func (w *huffmanBitWriter) writeTokens(tokens []token, leCodes, oeCodes []hcode) } else { // inlined c := lengths[lengthCode&31] - w.bits |= uint64(c.code) << (w.nbits & reg16SizeMask64) + w.bits |= uint64(c.code) << w.nbits w.nbits += c.len if w.nbits >= 48 { w.writeOutBits() @@ -779,7 +779,7 @@ func (w *huffmanBitWriter) writeTokens(tokens []token, leCodes, oeCodes []hcode) } else { // inlined c := offs[offsetCode&31] - w.bits |= uint64(c.code) << (w.nbits & reg16SizeMask64) + w.bits |= uint64(c.code) << w.nbits w.nbits += c.len if w.nbits >= 48 { w.writeOutBits() @@ -830,8 +830,8 @@ func (w *huffmanBitWriter) writeBlockHuff(eof bool, input []byte, sync bool) { // Assume header is around 70 bytes: // https://stackoverflow.com/a/25454430 const guessHeaderSizeBits = 70 * 8 - estBits, estExtra := histogramSize(input, w.literalFreq[:], !eof && !sync) - estBits += w.lastHeader + 15 + estBits := histogramSize(input, w.literalFreq[:], !eof && !sync) + estBits += w.lastHeader + len(input)/32 if w.lastHeader == 0 { estBits += guessHeaderSizeBits } @@ -845,9 +845,9 @@ func (w *huffmanBitWriter) writeBlockHuff(eof bool, input []byte, sync bool) { return } + reuseSize := 0 if w.lastHeader > 0 { - reuseSize := w.literalEncoding.bitLength(w.literalFreq[:256]) - estBits += estExtra + reuseSize = w.literalEncoding.bitLength(w.literalFreq[:256]) if estBits < reuseSize { // We owe an EOB @@ -859,6 +859,10 @@ func (w *huffmanBitWriter) writeBlockHuff(eof bool, input []byte, sync bool) { const numLiterals = endBlockMarker + 1 const numOffsets = 1 if w.lastHeader == 0 { + if !eof && !sync { + // Generate a slightly suboptimal tree that can be used for all. + fillHist(w.literalFreq[:numLiterals]) + } w.literalFreq[endBlockMarker] = 1 w.literalEncoding.generate(w.literalFreq[:numLiterals], 15) @@ -878,19 +882,14 @@ func (w *huffmanBitWriter) writeBlockHuff(eof bool, input []byte, sync bool) { for _, t := range input { // Bitwriting inlined, ~30% speedup c := encoding[t] - w.bits |= uint64(c.code) << ((w.nbits) & reg16SizeMask64) + w.bits |= uint64(c.code) << w.nbits w.nbits += c.len if w.nbits >= 48 { bits := w.bits w.bits >>= 48 w.nbits -= 48 n := w.nbytes - w.bytes[n] = byte(bits) - w.bytes[n+1] = byte(bits >> 8) - w.bytes[n+2] = byte(bits >> 16) - w.bytes[n+3] = byte(bits >> 24) - w.bytes[n+4] = byte(bits >> 32) - w.bytes[n+5] = byte(bits >> 40) + binary.LittleEndian.PutUint64(w.bytes[n:], bits) n += 6 if n >= bufferFlushSize { if w.err != nil { |