Signed-off-by: Miloslav Trmač <mitr@redhat.com>
This commit is contained in:
Miloslav Trmač
2023-01-23 16:22:08 +01:00
parent 47919520f5
commit 48b9d94c87
73 changed files with 11300 additions and 634 deletions

View File

@@ -146,54 +146,51 @@ func (s *Scratch) compress(src []byte) error {
c1.encodeZero(tt[src[ip-2]])
ip -= 2
}
src = src[:ip]
// Main compression loop.
switch {
case !s.zeroBits && s.actualTableLog <= 8:
// We can encode 4 symbols without requiring a flush.
// We do not need to check if any output is 0 bits.
for ip >= 4 {
for ; len(src) >= 4; src = src[:len(src)-4] {
s.bw.flush32()
v3, v2, v1, v0 := src[ip-4], src[ip-3], src[ip-2], src[ip-1]
v3, v2, v1, v0 := src[len(src)-4], src[len(src)-3], src[len(src)-2], src[len(src)-1]
c2.encode(tt[v0])
c1.encode(tt[v1])
c2.encode(tt[v2])
c1.encode(tt[v3])
ip -= 4
}
case !s.zeroBits:
// We do not need to check if any output is 0 bits.
for ip >= 4 {
for ; len(src) >= 4; src = src[:len(src)-4] {
s.bw.flush32()
v3, v2, v1, v0 := src[ip-4], src[ip-3], src[ip-2], src[ip-1]
v3, v2, v1, v0 := src[len(src)-4], src[len(src)-3], src[len(src)-2], src[len(src)-1]
c2.encode(tt[v0])
c1.encode(tt[v1])
s.bw.flush32()
c2.encode(tt[v2])
c1.encode(tt[v3])
ip -= 4
}
case s.actualTableLog <= 8:
// We can encode 4 symbols without requiring a flush
for ip >= 4 {
for ; len(src) >= 4; src = src[:len(src)-4] {
s.bw.flush32()
v3, v2, v1, v0 := src[ip-4], src[ip-3], src[ip-2], src[ip-1]
v3, v2, v1, v0 := src[len(src)-4], src[len(src)-3], src[len(src)-2], src[len(src)-1]
c2.encodeZero(tt[v0])
c1.encodeZero(tt[v1])
c2.encodeZero(tt[v2])
c1.encodeZero(tt[v3])
ip -= 4
}
default:
for ip >= 4 {
for ; len(src) >= 4; src = src[:len(src)-4] {
s.bw.flush32()
v3, v2, v1, v0 := src[ip-4], src[ip-3], src[ip-2], src[ip-1]
v3, v2, v1, v0 := src[len(src)-4], src[len(src)-3], src[len(src)-2], src[len(src)-1]
c2.encodeZero(tt[v0])
c1.encodeZero(tt[v1])
s.bw.flush32()
c2.encodeZero(tt[v2])
c1.encodeZero(tt[v3])
ip -= 4
}
}
@@ -459,15 +456,17 @@ func (s *Scratch) countSimple(in []byte) (max int) {
for _, v := range in {
s.count[v]++
}
m := uint32(0)
m, symlen := uint32(0), s.symbolLen
for i, v := range s.count[:] {
if v == 0 {
continue
}
if v > m {
m = v
}
if v > 0 {
s.symbolLen = uint16(i) + 1
}
symlen = uint16(i) + 1
}
s.symbolLen = symlen
return int(m)
}