vendor: update buildkit

Signed-off-by: CrazyMax <crazy-max@users.noreply.github.com>
This commit is contained in:
CrazyMax
2021-09-27 21:54:35 +02:00
parent c643c2ca95
commit eec1693f30
419 changed files with 20903 additions and 12229 deletions

View File

@ -245,6 +245,68 @@ func (c cTable) write(s *Scratch) error {
return nil
}
func (c cTable) estTableSize(s *Scratch) (sz int, err error) {
var (
// precomputed conversion table
bitsToWeight [tableLogMax + 1]byte
huffLog = s.actualTableLog
// last weight is not saved.
maxSymbolValue = uint8(s.symbolLen - 1)
huffWeight = s.huffWeight[:256]
)
const (
maxFSETableLog = 6
)
// convert to weight
bitsToWeight[0] = 0
for n := uint8(1); n < huffLog+1; n++ {
bitsToWeight[n] = huffLog + 1 - n
}
// Acquire histogram for FSE.
hist := s.fse.Histogram()
hist = hist[:256]
for i := range hist[:16] {
hist[i] = 0
}
for n := uint8(0); n < maxSymbolValue; n++ {
v := bitsToWeight[c[n].nBits] & 15
huffWeight[n] = v
hist[v]++
}
// FSE compress if feasible.
if maxSymbolValue >= 2 {
huffMaxCnt := uint32(0)
huffMax := uint8(0)
for i, v := range hist[:16] {
if v == 0 {
continue
}
huffMax = byte(i)
if v > huffMaxCnt {
huffMaxCnt = v
}
}
s.fse.HistogramFinished(huffMax, int(huffMaxCnt))
s.fse.TableLog = maxFSETableLog
b, err := fse.Compress(huffWeight[:maxSymbolValue], s.fse)
if err == nil && len(b) < int(s.symbolLen>>1) {
sz += 1 + len(b)
return sz, nil
}
// Unable to compress (RLE/uncompressible)
}
// write raw values as 4-bits (max : 15)
if maxSymbolValue > (256 - 128) {
// should not happen : likely means source cannot be compressed
return 0, ErrIncompressible
}
// special case, pack weights 4 bits/weight.
sz += 1 + int(maxSymbolValue/2)
return sz, nil
}
// estimateSize returns the estimated size in bytes of the input represented in the
// histogram supplied.
func (c cTable) estimateSize(hist []uint32) int {