diff options
Diffstat (limited to 'vendor/github.com/klauspost/compress/zstd/enc_better.go')
-rw-r--r-- | vendor/github.com/klauspost/compress/zstd/enc_better.go | 64 |
1 files changed, 33 insertions, 31 deletions
diff --git a/vendor/github.com/klauspost/compress/zstd/enc_better.go b/vendor/github.com/klauspost/compress/zstd/enc_better.go index eab7b5083..602c05ee0 100644 --- a/vendor/github.com/klauspost/compress/zstd/enc_better.go +++ b/vendor/github.com/klauspost/compress/zstd/enc_better.go @@ -9,6 +9,7 @@ import "fmt" const ( betterLongTableBits = 19 // Bits used in the long match table betterLongTableSize = 1 << betterLongTableBits // Size of the table + betterLongLen = 8 // Bytes used for table hash // Note: Increasing the short table bits or making the hash shorter // can actually lead to compression degradation since it will 'steal' more from the @@ -16,6 +17,7 @@ const ( // This greatly depends on the type of input. betterShortTableBits = 13 // Bits used in the short match table betterShortTableSize = 1 << betterShortTableBits // Size of the table + betterShortLen = 5 // Bytes used for table hash betterLongTableShardCnt = 1 << (betterLongTableBits - dictShardBits) // Number of shards in the table betterLongTableShardSize = betterLongTableSize / betterLongTableShardCnt // Size of an individual shard @@ -154,8 +156,8 @@ encodeLoop: panic("offset0 was 0") } - nextHashS := hash5(cv, betterShortTableBits) - nextHashL := hash8(cv, betterLongTableBits) + nextHashS := hashLen(cv, betterShortTableBits, betterShortLen) + nextHashL := hashLen(cv, betterLongTableBits, betterLongLen) candidateL := e.longTable[nextHashL] candidateS := e.table[nextHashS] @@ -214,10 +216,10 @@ encodeLoop: for index0 < s-1 { cv0 := load6432(src, index0) cv1 := cv0 >> 8 - h0 := hash8(cv0, betterLongTableBits) + h0 := hashLen(cv0, betterLongTableBits, betterLongLen) off := index0 + e.cur e.longTable[h0] = prevEntry{offset: off, prev: e.longTable[h0].offset} - e.table[hash5(cv1, betterShortTableBits)] = tableEntry{offset: off + 1, val: uint32(cv1)} + e.table[hashLen(cv1, betterShortTableBits, betterShortLen)] = tableEntry{offset: off + 1, val: uint32(cv1)} index0 += 2 } cv = load6432(src, s) @@ -275,10 +277,10 @@ encodeLoop: for index0 < s-1 { cv0 := load6432(src, index0) cv1 := cv0 >> 8 - h0 := hash8(cv0, betterLongTableBits) + h0 := hashLen(cv0, betterLongTableBits, betterLongLen) off := index0 + e.cur e.longTable[h0] = prevEntry{offset: off, prev: e.longTable[h0].offset} - e.table[hash5(cv1, betterShortTableBits)] = tableEntry{offset: off + 1, val: uint32(cv1)} + e.table[hashLen(cv1, betterShortTableBits, betterShortLen)] = tableEntry{offset: off + 1, val: uint32(cv1)} index0 += 2 } cv = load6432(src, s) @@ -353,7 +355,7 @@ encodeLoop: // See if we can find a long match at s+1 const checkAt = 1 cv := load6432(src, s+checkAt) - nextHashL = hash8(cv, betterLongTableBits) + nextHashL = hashLen(cv, betterLongTableBits, betterLongLen) candidateL = e.longTable[nextHashL] coffsetL = candidateL.offset - e.cur @@ -413,8 +415,8 @@ encodeLoop: } // Try to find a better match by searching for a long match at the end of the current best match - if true && s+matched < sLimit { - nextHashL := hash8(load6432(src, s+matched), betterLongTableBits) + if s+matched < sLimit { + nextHashL := hashLen(load6432(src, s+matched), betterLongTableBits, betterLongLen) cv := load3232(src, s) candidateL := e.longTable[nextHashL] coffsetL := candidateL.offset - e.cur - matched @@ -495,10 +497,10 @@ encodeLoop: for index0 < s-1 { cv0 := load6432(src, index0) cv1 := cv0 >> 8 - h0 := hash8(cv0, betterLongTableBits) + h0 := hashLen(cv0, betterLongTableBits, betterLongLen) off := index0 + e.cur e.longTable[h0] = prevEntry{offset: off, prev: e.longTable[h0].offset} - e.table[hash5(cv1, betterShortTableBits)] = tableEntry{offset: off + 1, val: uint32(cv1)} + e.table[hashLen(cv1, betterShortTableBits, betterShortLen)] = tableEntry{offset: off + 1, val: uint32(cv1)} index0 += 2 } @@ -516,8 +518,8 @@ encodeLoop: } // Store this, since we have it. - nextHashS := hash5(cv, betterShortTableBits) - nextHashL := hash8(cv, betterLongTableBits) + nextHashS := hashLen(cv, betterShortTableBits, betterShortLen) + nextHashL := hashLen(cv, betterLongTableBits, betterLongLen) // We have at least 4 byte match. // No need to check backwards. We come straight from a match @@ -672,8 +674,8 @@ encodeLoop: panic("offset0 was 0") } - nextHashS := hash5(cv, betterShortTableBits) - nextHashL := hash8(cv, betterLongTableBits) + nextHashS := hashLen(cv, betterShortTableBits, betterShortLen) + nextHashL := hashLen(cv, betterLongTableBits, betterLongLen) candidateL := e.longTable[nextHashL] candidateS := e.table[nextHashS] @@ -734,11 +736,11 @@ encodeLoop: for index0 < s-1 { cv0 := load6432(src, index0) cv1 := cv0 >> 8 - h0 := hash8(cv0, betterLongTableBits) + h0 := hashLen(cv0, betterLongTableBits, betterLongLen) off := index0 + e.cur e.longTable[h0] = prevEntry{offset: off, prev: e.longTable[h0].offset} e.markLongShardDirty(h0) - h1 := hash5(cv1, betterShortTableBits) + h1 := hashLen(cv1, betterShortTableBits, betterShortLen) e.table[h1] = tableEntry{offset: off + 1, val: uint32(cv1)} e.markShortShardDirty(h1) index0 += 2 @@ -798,11 +800,11 @@ encodeLoop: for index0 < s-1 { cv0 := load6432(src, index0) cv1 := cv0 >> 8 - h0 := hash8(cv0, betterLongTableBits) + h0 := hashLen(cv0, betterLongTableBits, betterLongLen) off := index0 + e.cur e.longTable[h0] = prevEntry{offset: off, prev: e.longTable[h0].offset} e.markLongShardDirty(h0) - h1 := hash5(cv1, betterShortTableBits) + h1 := hashLen(cv1, betterShortTableBits, betterShortLen) e.table[h1] = tableEntry{offset: off + 1, val: uint32(cv1)} e.markShortShardDirty(h1) index0 += 2 @@ -879,7 +881,7 @@ encodeLoop: // See if we can find a long match at s+1 const checkAt = 1 cv := load6432(src, s+checkAt) - nextHashL = hash8(cv, betterLongTableBits) + nextHashL = hashLen(cv, betterLongTableBits, betterLongLen) candidateL = e.longTable[nextHashL] coffsetL = candidateL.offset - e.cur @@ -940,7 +942,7 @@ encodeLoop: } // Try to find a better match by searching for a long match at the end of the current best match if s+matched < sLimit { - nextHashL := hash8(load6432(src, s+matched), betterLongTableBits) + nextHashL := hashLen(load6432(src, s+matched), betterLongTableBits, betterLongLen) cv := load3232(src, s) candidateL := e.longTable[nextHashL] coffsetL := candidateL.offset - e.cur - matched @@ -1021,11 +1023,11 @@ encodeLoop: for index0 < s-1 { cv0 := load6432(src, index0) cv1 := cv0 >> 8 - h0 := hash8(cv0, betterLongTableBits) + h0 := hashLen(cv0, betterLongTableBits, betterLongLen) off := index0 + e.cur e.longTable[h0] = prevEntry{offset: off, prev: e.longTable[h0].offset} e.markLongShardDirty(h0) - h1 := hash5(cv1, betterShortTableBits) + h1 := hashLen(cv1, betterShortTableBits, betterShortLen) e.table[h1] = tableEntry{offset: off + 1, val: uint32(cv1)} e.markShortShardDirty(h1) index0 += 2 @@ -1045,8 +1047,8 @@ encodeLoop: } // Store this, since we have it. - nextHashS := hash5(cv, betterShortTableBits) - nextHashL := hash8(cv, betterLongTableBits) + nextHashS := hashLen(cv, betterShortTableBits, betterShortLen) + nextHashL := hashLen(cv, betterLongTableBits, betterLongLen) // We have at least 4 byte match. // No need to check backwards. We come straight from a match @@ -1113,10 +1115,10 @@ func (e *betterFastEncoderDict) Reset(d *dict, singleBlock bool) { const hashLog = betterShortTableBits cv := load6432(d.content, i-e.maxMatchOff) - nextHash := hash5(cv, hashLog) // 0 -> 4 - nextHash1 := hash5(cv>>8, hashLog) // 1 -> 5 - nextHash2 := hash5(cv>>16, hashLog) // 2 -> 6 - nextHash3 := hash5(cv>>24, hashLog) // 3 -> 7 + nextHash := hashLen(cv, hashLog, betterShortLen) // 0 -> 4 + nextHash1 := hashLen(cv>>8, hashLog, betterShortLen) // 1 -> 5 + nextHash2 := hashLen(cv>>16, hashLog, betterShortLen) // 2 -> 6 + nextHash3 := hashLen(cv>>24, hashLog, betterShortLen) // 3 -> 7 e.dictTable[nextHash] = tableEntry{ val: uint32(cv), offset: i, @@ -1145,7 +1147,7 @@ func (e *betterFastEncoderDict) Reset(d *dict, singleBlock bool) { } if len(d.content) >= 8 { cv := load6432(d.content, 0) - h := hash8(cv, betterLongTableBits) + h := hashLen(cv, betterLongTableBits, betterLongLen) e.dictLongTable[h] = prevEntry{ offset: e.maxMatchOff, prev: e.dictLongTable[h].offset, @@ -1155,7 +1157,7 @@ func (e *betterFastEncoderDict) Reset(d *dict, singleBlock bool) { off := 8 // First to read for i := e.maxMatchOff + 1; i < end; i++ { cv = cv>>8 | (uint64(d.content[off]) << 56) - h := hash8(cv, betterLongTableBits) + h := hashLen(cv, betterLongTableBits, betterLongLen) e.dictLongTable[h] = prevEntry{ offset: i, prev: e.dictLongTable[h].offset, |