facebook/zstd
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Shorten Dict Mode Conditionals in Order to Improve Readability

Browse Source
This commit is contained in:
W. Felix Handte 2020-09-02 13:27:11 -04:00
parent f49c1563ff
commit d214d8c859
1 changed files with 14 additions and 13 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

27
lib/compress/zstd_lazy.c
View File

@ -785,16 +785,18 @@ ZSTD_compressBlock_lazy_generic(
searchMax_f const searchMax = searchFuncs[dictMode][searchMethod == search_binaryTree];
U32 offset_1 = rep[0], offset_2 = rep[1], savedOffset=0;
const int isDMS = dictMode == ZSTD_dictMatchState;
const int isDDS = dictMode == ZSTD_dedicatedDictSearch;
const ZSTD_matchState_t* const dms = ms->dictMatchState;
const U32 dictLowestIndex = dictMode == ZSTD_dictMatchState || dictMode == ZSTD_dedicatedDictSearch ?
const U32 dictLowestIndex = isDMS || isDDS ?
dms->window.dictLimit : 0;
const BYTE* const dictBase = dictMode == ZSTD_dictMatchState || dictMode == ZSTD_dedicatedDictSearch ?
const BYTE* const dictBase = isDMS || isDDS ?
dms->window.base : NULL;
const BYTE* const dictLowest = dictMode == ZSTD_dictMatchState || dictMode == ZSTD_dedicatedDictSearch ?
const BYTE* const dictLowest = isDMS || isDDS ?
dictBase + dictLowestIndex : NULL;
const BYTE* const dictEnd = dictMode == ZSTD_dictMatchState || dictMode == ZSTD_dedicatedDictSearch ?
const BYTE* const dictEnd = isDMS || isDDS ?
dms->window.nextSrc : NULL;
const U32 dictIndexDelta = dictMode == ZSTD_dictMatchState || dictMode == ZSTD_dedicatedDictSearch ?
const U32 dictIndexDelta = isDMS || isDDS ?
prefixLowestIndex - (U32)(dictEnd - dictBase) :
0;
const U32 dictAndPrefixLength = (U32)((ip - prefixLowest) + (dictEnd - dictLowest));
@ -812,7 +814,7 @@ ZSTD_compressBlock_lazy_generic(
if (offset_2 > maxRep) savedOffset = offset_2, offset_2 = 0;
if (offset_1 > maxRep) savedOffset = offset_1, offset_1 = 0;
}
if (dictMode == ZSTD_dictMatchState || dictMode == ZSTD_dedicatedDictSearch) {
if (isDMS || isDDS) {
/* dictMatchState repCode checks don't currently handle repCode == 0
* disabling. */
assert(offset_1 <= dictAndPrefixLength);
@ -832,7 +834,7 @@ ZSTD_compressBlock_lazy_generic(
const BYTE* start=ip+1;
/* check repCode */
if (dictMode == ZSTD_dictMatchState || dictMode == ZSTD_dedicatedDictSearch) {
if (isDMS || isDDS) {
const U32 repIndex = (U32)(ip - base) + 1 - offset_1;
const BYTE* repMatch = ((dictMode == ZSTD_dictMatchState || dictMode == ZSTD_dedicatedDictSearch)
&& repIndex < prefixLowestIndex) ?
@ -875,7 +877,7 @@ ZSTD_compressBlock_lazy_generic(
if ((mlRep >= 4) && (gain2 > gain1))
matchLength = mlRep, offset = 0, start = ip;
}
if (dictMode == ZSTD_dictMatchState || dictMode == ZSTD_dedicatedDictSearch) {
if (isDMS || isDDS) {
const U32 repIndex = (U32)(ip - base) - offset_1;
const BYTE* repMatch = repIndex < prefixLowestIndex ?
dictBase + (repIndex - dictIndexDelta) :
@ -910,7 +912,7 @@ ZSTD_compressBlock_lazy_generic(
if ((mlRep >= 4) && (gain2 > gain1))
matchLength = mlRep, offset = 0, start = ip;
}
if (dictMode == ZSTD_dictMatchState || dictMode == ZSTD_dedicatedDictSearch) {
if (isDMS || isDDS) {
const U32 repIndex = (U32)(ip - base) - offset_1;
const BYTE* repMatch = repIndex < prefixLowestIndex ?
dictBase + (repIndex - dictIndexDelta) :
@ -948,7 +950,7 @@ ZSTD_compressBlock_lazy_generic(
&& (start[-1] == (start-(offset-ZSTD_REP_MOVE))[-1]) ) /* only search for offset within prefix */
{ start--; matchLength++; }
}
if (dictMode == ZSTD_dictMatchState || dictMode == ZSTD_dedicatedDictSearch) {
if (isDMS || isDDS) {
U32 const matchIndex = (U32)((start-base) - (offset - ZSTD_REP_MOVE));
const BYTE* match = (matchIndex < prefixLowestIndex) ? dictBase + matchIndex - dictIndexDelta : base + matchIndex;
const BYTE* const mStart = (matchIndex < prefixLowestIndex) ? dictLowest : prefixLowest;
@ -964,12 +966,11 @@ _storeSequence:
}
/* check immediate repcode */
if (dictMode == ZSTD_dictMatchState || dictMode == ZSTD_dedicatedDictSearch) {
if (isDMS || isDDS) {
while (ip <= ilimit) {
U32 const current2 = (U32)(ip-base);
U32 const repIndex = current2 - offset_2;
const BYTE* repMatch = (dictMode == ZSTD_dictMatchState || dictMode == ZSTD_dedicatedDictSearch)
&& repIndex < prefixLowestIndex ?
const BYTE* repMatch = repIndex < prefixLowestIndex ?
dictBase - dictIndexDelta + repIndex :
base + repIndex;
if ( ((U32)((prefixLowestIndex-1) - (U32)repIndex) >= 3 /* intentional overflow */)