diff options
Diffstat (limited to 'vendor/github.com/klauspost/compress/flate/level3.go')
| -rw-r--r-- | vendor/github.com/klauspost/compress/flate/level3.go | 54 |
1 files changed, 26 insertions, 28 deletions
diff --git a/vendor/github.com/klauspost/compress/flate/level3.go b/vendor/github.com/klauspost/compress/flate/level3.go index 1a3ff9b6b..c22b4244a 100644 --- a/vendor/github.com/klauspost/compress/flate/level3.go +++ b/vendor/github.com/klauspost/compress/flate/level3.go @@ -15,7 +15,7 @@ func (e *fastEncL3) Encode(dst *tokens, src []byte) { minNonLiteralBlockSize = 1 + 1 + inputMargin ) - if debugDecode && e.cur < 0 { + if debugDeflate && e.cur < 0 { panic(fmt.Sprint("e.cur < 0: ", e.cur)) } @@ -81,22 +81,26 @@ func (e *fastEncL3) Encode(dst *tokens, src []byte) { } candidates := e.table[nextHash] now := load3232(src, nextS) - e.table[nextHash] = tableEntryPrev{Prev: candidates.Cur, Cur: tableEntry{offset: s + e.cur, val: cv}} + + // Safe offset distance until s + 4... + minOffset := e.cur + s - (maxMatchOffset - 4) + e.table[nextHash] = tableEntryPrev{Prev: candidates.Cur, Cur: tableEntry{offset: s + e.cur}} // Check both candidates candidate = candidates.Cur - offset := s - (candidate.offset - e.cur) - if cv == candidate.val { - if offset > maxMatchOffset { - cv = now - // Previous will also be invalid, we have nothing. - continue - } - o2 := s - (candidates.Prev.offset - e.cur) - if cv != candidates.Prev.val || o2 > maxMatchOffset { + if candidate.offset < minOffset { + cv = now + // Previous will also be invalid, we have nothing. + continue + } + + if cv == load3232(src, candidate.offset-e.cur) { + if candidates.Prev.offset < minOffset || cv != load3232(src, candidates.Prev.offset-e.cur) { break } // Both match and are valid, pick longest. + offset := s - (candidate.offset - e.cur) + o2 := s - (candidates.Prev.offset - e.cur) l1, l2 := matchLen(src[s+4:], src[s-offset+4:]), matchLen(src[s+4:], src[s-o2+4:]) if l2 > l1 { candidate = candidates.Prev @@ -106,11 +110,8 @@ func (e *fastEncL3) Encode(dst *tokens, src []byte) { // We only check if value mismatches. // Offset will always be invalid in other cases. candidate = candidates.Prev - if cv == candidate.val { - offset := s - (candidate.offset - e.cur) - if offset <= maxMatchOffset { - break - } + if candidate.offset > minOffset && cv == load3232(src, candidate.offset-e.cur) { + break } } cv = now @@ -158,7 +159,7 @@ func (e *fastEncL3) Encode(dst *tokens, src []byte) { nextHash := hash(cv) e.table[nextHash] = tableEntryPrev{ Prev: e.table[nextHash].Cur, - Cur: tableEntry{offset: e.cur + t, val: cv}, + Cur: tableEntry{offset: e.cur + t}, } } goto emitRemainder @@ -170,21 +171,21 @@ func (e *fastEncL3) Encode(dst *tokens, src []byte) { prevHash := hash(uint32(x)) e.table[prevHash] = tableEntryPrev{ Prev: e.table[prevHash].Cur, - Cur: tableEntry{offset: e.cur + s - 3, val: uint32(x)}, + Cur: tableEntry{offset: e.cur + s - 3}, } x >>= 8 prevHash = hash(uint32(x)) e.table[prevHash] = tableEntryPrev{ Prev: e.table[prevHash].Cur, - Cur: tableEntry{offset: e.cur + s - 2, val: uint32(x)}, + Cur: tableEntry{offset: e.cur + s - 2}, } x >>= 8 prevHash = hash(uint32(x)) e.table[prevHash] = tableEntryPrev{ Prev: e.table[prevHash].Cur, - Cur: tableEntry{offset: e.cur + s - 1, val: uint32(x)}, + Cur: tableEntry{offset: e.cur + s - 1}, } x >>= 8 currHash := hash(uint32(x)) @@ -192,21 +193,18 @@ func (e *fastEncL3) Encode(dst *tokens, src []byte) { cv = uint32(x) e.table[currHash] = tableEntryPrev{ Prev: candidates.Cur, - Cur: tableEntry{offset: s + e.cur, val: cv}, + Cur: tableEntry{offset: s + e.cur}, } // Check both candidates candidate = candidates.Cur - if cv == candidate.val { - offset := s - (candidate.offset - e.cur) - if offset <= maxMatchOffset { - continue - } - } else { + minOffset := e.cur + s - (maxMatchOffset - 4) + + if candidate.offset > minOffset && cv != load3232(src, candidate.offset-e.cur) { // We only check if value mismatches. // Offset will always be invalid in other cases. candidate = candidates.Prev - if cv == candidate.val { + if candidate.offset > minOffset && cv == load3232(src, candidate.offset-e.cur) { offset := s - (candidate.offset - e.cur) if offset <= maxMatchOffset { continue |