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[zstd] Backport kernel patch from @ColinIanKing

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* Make the U32 table in `FSE_normalizeCount()` static.
* Patch from https://lkml.kernel.org/r/20170922145946.14316-1-colin.king@canonical.com.
* Clang makes non-static tables static anyways. gcc however, does [weird things](https://godbolt.org/g/fvTcED).
* Benchmarks showed no difference in speed.
This commit is contained in:
Nick Terrell
2017-09-25 16:12:46 -07:00
parent 8977224b9b
commit 76cb38d085
1 changed files with 1 additions and 1 deletions
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lib/compress/fse_compress.c
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@@ -582,7 +582,7 @@ size_t FSE_normalizeCount (short* normalizedCounter, unsigned tableLog,
if (tableLog > FSE_MAX_TABLELOG) return ERROR(tableLog_tooLarge); /* Unsupported size */
if (tableLog < FSE_minTableLog(total, maxSymbolValue)) return ERROR(GENERIC); /* Too small tableLog, compression potentially impossible */
{ U32 const rtbTable[] = { 0, 473195, 504333, 520860, 550000, 700000, 750000, 830000 };
{ static U32 const rtbTable[] = { 0, 473195, 504333, 520860, 550000, 700000, 750000, 830000 };
U64 const scale = 62 - tableLog;
U64 const step = ((U64)1<<62) / total; /* <== here, one division ! */
U64 const vStep = 1ULL<<(scale-20);