AuroraMiddleware/zstd
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity
5,155 Commits 1 Branch 0 Tags 27 MiB
143fc9ff6c
Commit Graph

2306 Commits

Author SHA1 Message Date
Yann Collet
143fc9ff6c
Merge pull request #1157 from facebook/decompressedSize 
minor : improved zstd.h API code comment
 2018-06-01 10:28:17 -07:00
Yann Collet
7c33b48221
Merge pull request #1151 from felixhandte/zstd-dfast-in-place-dict-goto 
ZSTD_dfast: Support Searching the Dictionary Context In-Place (Alternate `goto` Implementation)
 2018-05-31 17:37:09 -07:00
W. Felix Handte
48deab92de Allow Different Dict Attachment Cut-Offs for Different Strategies 2018-05-31 17:37:44 -04:00
W. Felix Handte
f86796639e Remove Incorrect and Extraneous Repcode Bounds Check 2018-05-31 17:02:29 -04:00
Yann Collet
9b979d0e33 minor : improved API code comment 
Extend guarantee that ZSTD_getFrameContentSize() will delivering the decompressed size
to any single-pass compression function.

Answer #1156
 2018-05-31 11:12:18 -07:00
Yann Collet
809f2f9322 minor update of literal cost function 
just assert() there is no negative cost evaluation for literals
 2018-05-29 15:34:50 -07:00
Yann Collet
463a0fe38b simplified optimal parser 
removed "cached" structure.
prices are now saved in the optimal table.

Primarily done for simplification.
Might improve speed by a little.
But actually, and surprisingly, also improves ratio in some circumstances.
 2018-05-29 14:07:25 -07:00
Yann Collet
bb6eaf6495
Merge pull request #1153 from facebook/dynThreshold 
changed dynamic fse threshold for offset
 2018-05-26 08:43:45 -07:00
Yann Collet
e916c365a1 fixed minor visual warning 2018-05-25 20:43:09 -07:00
Yann Collet
a7fdceeccd changed dynamic fse threshold for offset 
recent experienced showed that
default distribution table for offset
can get it wrong pretty quickly with the nb of symbols,
while it remains a reasonable choice much longer for lengths symbols.

Changed the formula,
so that dynamic threshold is now 32 symbols for offsets.
It remains at 64 symbols for lengths.

Detection based on defaultNormLog
 2018-05-25 17:41:16 -07:00
Yann Collet
4b3a36d5d8 Merge branch 'dev' into lowCompression 2018-05-25 15:45:03 -07:00
Yann Collet
5f177f1c53 btultra accepts blocks with poorer compression ratio 
zstd rejects blocks which do not compress by at least a certain amount.
In which case, such block is simply emitted uncompressed (even if a little bit of compression could be achieved).
This is better for decompression speed, hence for energy.

The logic is controlled by ZSTD_minGain().
The rule is applied uniformly, at all compression levels.

This change makes btultra accepts blocks with poor compression ratios.
We presume that users of btultra mode prefers compression ratio over some decompress speed gains.

The threshold for minimum gain is lowered for btultra
from s>>6 (~1.5% minimum gain)
to s>>7 (~0.8% minimum gain).

This is a prudent change.
Not sure if it's large enough.
 2018-05-25 15:19:52 -07:00
Yann Collet
e2c0e3d437 slightly nudge choices towards less sequences 
also slightly improve some strange detrimental corner cases.
 2018-05-25 14:52:21 -07:00
W. Felix Handte
5b292b5685 Check Long + 1 Matches in Both Prefix and Dict in Bothe Short Match Paths 2018-05-25 13:13:57 -04:00
W. Felix Handte
88b733b380 Interleave Prefix and Dict Searches 2018-05-25 13:13:57 -04:00
W. Felix Handte
1850025156 Refactor ZSTD_dfast to Use gotos 2018-05-25 13:13:57 -04:00
W. Felix Handte
43606f9c83 ... When I Said "HashTable", I Meant "ChainTable" 2018-05-25 13:13:28 -04:00
W. Felix Handte
ec7efe88f5 Fix Off-By-One Error 2018-05-25 13:13:28 -04:00
W. Felix Handte
2bfe43267e Disallow Too-Long Repcodes When Using an Attached Dict 2018-05-25 13:13:28 -04:00
W. Felix Handte
b97ad3f457 Port Changes Made to ZSTD_fast to ZSTD_dfast 2018-05-25 13:13:28 -04:00
W. Felix Handte
2313cca1b7 Implement Second Repcode Check 2018-05-25 13:13:28 -04:00
W. Felix Handte
0998f10813 Implement First Repcode Check 2018-05-25 13:13:28 -04:00
W. Felix Handte
50c5b2bb90 Find Dict Hash Table Matches 2018-05-25 13:13:28 -04:00
W. Felix Handte
7a25f7ef5b Existing Repcode Check Only Applies to noDict Case 2018-05-25 13:13:28 -04:00
W. Felix Handte
8b241da4df Properly Initialize Repcode Values 2018-05-25 13:13:28 -04:00
W. Felix Handte
7097a03749 Add Necessary Dict Variables 2018-05-25 13:13:28 -04:00
W. Felix Handte
aacbbf4f9a Rename 'lowest' to 'localLowest' to Prepare to Introduce Dict Indices 2018-05-25 13:13:28 -04:00
W. Felix Handte
c10d1b4011 Skeleton for In-Place Impl for ZSTD_dfast 2018-05-25 13:13:28 -04:00
Yann Collet
f6ad59ab5c Merge branch 'dev' into staticDictCost 2018-05-24 16:21:02 -07:00
Yann Collet
b5ef32fea7 Merge branch 'dev' into fracFse 2018-05-24 14:09:49 -07:00
Yann Collet
776128d16f fix corner case when requiring cost of an FSE symbol 
ensure that, when frequency[symbol]==0,
result is (tableLog + 1) bits
with both upper-bit and fractional-bit estimates.

Also : enable BIT_DEBUG in /tests
 2018-05-24 13:59:11 -07:00
Yann Collet
08c5be5db3
Merge pull request #1117 from felixhandte/zstd-fast-in-place-dict 
ZSTD_fast: Support Searching the Dictionary Context In-Place
 2018-05-23 19:32:25 -07:00
Nick Terrell
06b70179da
Work around bug in zstd decoder (#1147) 
Work around bug in zstd decoder

Pull request #1144 exercised a new path in the zstd decoder that proved to
be buggy. Avoid the extremely rare bug by emitting an uncompressed block.
 2018-05-23 18:02:30 -07:00
Nick Terrell
f2d0924b87 Variable declarations 2018-05-23 14:58:58 -07:00
W. Felix Handte
d9c7e67125 Assert that Dict and Current Window are Adjacent in Index Space 2018-05-23 17:53:03 -04:00
W. Felix Handte
298d24fa57 Make loadedDictEnd an Index, not the Dict Len 2018-05-23 17:53:03 -04:00
W. Felix Handte
7ef85e0618 Fixes in re Comments 2018-05-23 17:53:03 -04:00
W. Felix Handte
582b7f85ed Don't Attach Empty Dict Contents 
In weird corner cases, they produce unexpected results...
 2018-05-23 17:53:03 -04:00
W. Felix Handte
9c92223468 Avoid Undefined Behavior in Match Ptr Calculation 2018-05-23 17:53:03 -04:00
W. Felix Handte
a44ab3b475 Remove Out-of-Date Comment 2018-05-23 17:53:03 -04:00
W. Felix Handte
95bdf20a87 Moar Renames 2018-05-23 17:53:03 -04:00
W. Felix Handte
7e0402e738 Also Attach Dict When Source Size is Unknown 2018-05-23 17:53:03 -04:00
W. Felix Handte
3ba70cc759 Clear the Dictionary When Sliding the Window 2018-05-23 17:53:03 -04:00
W. Felix Handte
b05ae9b608 Refine ip Initialization to Avoid ARM Weirdness 2018-05-23 17:53:03 -04:00
W. Felix Handte
1a7b34ef28 Use New Index Invariant to Simplify Conditionals 2018-05-23 17:53:03 -04:00
W. Felix Handte
2d598e6fed Force Working Context Indices Greater than Dict Indices 2018-05-23 17:53:03 -04:00
W. Felix Handte
d005e5daf4 Whitespace Fix 2018-05-23 17:53:03 -04:00
W. Felix Handte
154eb09419 Switch to Original Match Calc for noDict Repcode Check 2018-05-23 17:53:03 -04:00
W. Felix Handte
191fc74a51 Rename 'hasDict' to 'dictMode' 2018-05-23 17:53:03 -04:00
W. Felix Handte
ae4fcf7816 Respond to PR Comments; Formatting/Style/Lint Fixes 2018-05-23 17:53:03 -04:00