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Diffstat (limited to 'thirdparty/zstd/compress/zstd_double_fast.c')
-rw-r--r--thirdparty/zstd/compress/zstd_double_fast.c19
1 files changed, 11 insertions, 8 deletions
diff --git a/thirdparty/zstd/compress/zstd_double_fast.c b/thirdparty/zstd/compress/zstd_double_fast.c
index a661a48534..27eed66cfe 100644
--- a/thirdparty/zstd/compress/zstd_double_fast.c
+++ b/thirdparty/zstd/compress/zstd_double_fast.c
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2016-present, Yann Collet, Facebook, Inc.
+ * Copyright (c) 2016-2020, Yann Collet, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under both the BSD-style license (found in the
@@ -63,10 +63,8 @@ size_t ZSTD_compressBlock_doubleFast_generic(
const BYTE* ip = istart;
const BYTE* anchor = istart;
const U32 endIndex = (U32)((size_t)(istart - base) + srcSize);
- const U32 lowestValid = ms->window.dictLimit;
- const U32 maxDistance = 1U << cParams->windowLog;
/* presumes that, if there is a dictionary, it must be using Attach mode */
- const U32 prefixLowestIndex = (endIndex - lowestValid > maxDistance) ? endIndex - maxDistance : lowestValid;
+ const U32 prefixLowestIndex = ZSTD_getLowestPrefixIndex(ms, endIndex, cParams->windowLog);
const BYTE* const prefixLowest = base + prefixLowestIndex;
const BYTE* const iend = istart + srcSize;
const BYTE* const ilimit = iend - HASH_READ_SIZE;
@@ -96,7 +94,7 @@ size_t ZSTD_compressBlock_doubleFast_generic(
dictCParams->hashLog : hBitsL;
const U32 dictHBitsS = dictMode == ZSTD_dictMatchState ?
dictCParams->chainLog : hBitsS;
- const U32 dictAndPrefixLength = (U32)(ip - prefixLowest + dictEnd - dictStart);
+ const U32 dictAndPrefixLength = (U32)((ip - prefixLowest) + (dictEnd - dictStart));
DEBUGLOG(5, "ZSTD_compressBlock_doubleFast_generic");
@@ -104,13 +102,15 @@ size_t ZSTD_compressBlock_doubleFast_generic(
/* if a dictionary is attached, it must be within window range */
if (dictMode == ZSTD_dictMatchState) {
- assert(lowestValid + maxDistance >= endIndex);
+ assert(ms->window.dictLimit + (1U << cParams->windowLog) >= endIndex);
}
/* init */
ip += (dictAndPrefixLength == 0);
if (dictMode == ZSTD_noDict) {
- U32 const maxRep = (U32)(ip - prefixLowest);
+ U32 const current = (U32)(ip - base);
+ U32 const windowLow = ZSTD_getLowestPrefixIndex(ms, current, cParams->windowLog);
+ U32 const maxRep = current - windowLow;
if (offset_2 > maxRep) offsetSaved = offset_2, offset_2 = 0;
if (offset_1 > maxRep) offsetSaved = offset_1, offset_1 = 0;
}
@@ -198,6 +198,9 @@ size_t ZSTD_compressBlock_doubleFast_generic(
} }
ip += ((ip-anchor) >> kSearchStrength) + 1;
+#if defined(__aarch64__)
+ PREFETCH_L1(ip+256);
+#endif
continue;
_search_next_long:
@@ -271,7 +274,7 @@ _match_stored:
U32 const repIndex2 = current2 - offset_2;
const BYTE* repMatch2 = dictMode == ZSTD_dictMatchState
&& repIndex2 < prefixLowestIndex ?
- dictBase - dictIndexDelta + repIndex2 :
+ dictBase + repIndex2 - dictIndexDelta :
base + repIndex2;
if ( ((U32)((prefixLowestIndex-1) - (U32)repIndex2) >= 3 /* intentional overflow */)
&& (MEM_read32(repMatch2) == MEM_read32(ip)) ) {