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Extract Working Variables

dev
W. Felix Handte 2021-09-02 12:03:49 -04:00
parent 1bdf041071
commit 072ffaad67
1 changed files with 43 additions and 27 deletions
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70
lib/compress/zstd_double_fast.c
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@ -74,6 +74,21 @@ size_t ZSTD_compressBlock_doubleFast_singleSegment_generic(
const size_t kStepIncr = 1 << kSearchStrength;
const BYTE* nextStep = ip + kStepIncr;
size_t hl0;
size_t hs0;
size_t hl1;
// size_t hs1;
U32 idxl0;
U32 idxs0;
U32 idxl1;
// U32 idxs0;
const BYTE* matchl0;
const BYTE* matchs0;
const BYTE* matchl1;
// const BYTE* matchs1;
DEBUGLOG(5, "ZSTD_compressBlock_doubleFast_singleSegment_generic");
/* init */
@ -90,14 +105,15 @@ size_t ZSTD_compressBlock_doubleFast_singleSegment_generic(
while (ip < ilimit) { /* < instead of <=, because repcode check at (ip+1) */
size_t mLength;
U32 offset;
size_t const h2 = ZSTD_hashPtr(ip, hBitsL, 8);
size_t const h = ZSTD_hashPtr(ip, hBitsS, mls);
U32 const curr = (U32)(ip-base);
U32 const matchIndexL = hashLong[h2];
U32 matchIndexS = hashSmall[h];
const BYTE* matchLong = base + matchIndexL;
const BYTE* match = base + matchIndexS;
hashLong[h2] = hashSmall[h] = curr; /* update hash tables */
hl0 = ZSTD_hashPtr(ip, hBitsL, 8);
hs0 = ZSTD_hashPtr(ip, hBitsS, mls);
idxl0 = hashLong[hl0];
idxs0 = hashSmall[hs0];
matchl0 = base + idxl0;
matchs0 = base + idxs0;
hashLong[hl0] = hashSmall[hs0] = curr; /* update hash tables */
/* check noDict repcode */
if ((offset_1 > 0) & (MEM_read32(ip+1-offset_1) == MEM_read32(ip+1))) {
@ -107,19 +123,19 @@ size_t ZSTD_compressBlock_doubleFast_singleSegment_generic(
goto _match_stored;
}
if (matchIndexL > prefixLowestIndex) {
if (idxl0 > prefixLowestIndex) {
/* check prefix long match */
if (MEM_read64(matchLong) == MEM_read64(ip)) {
mLength = ZSTD_count(ip+8, matchLong+8, iend) + 8;
offset = (U32)(ip-matchLong);
while (((ip>anchor) & (matchLong>prefixLowest)) && (ip[-1] == matchLong[-1])) { ip--; matchLong--; mLength++; } /* catch up */
if (MEM_read64(matchl0) == MEM_read64(ip)) {
mLength = ZSTD_count(ip+8, matchl0+8, iend) + 8;
offset = (U32)(ip-matchl0);
while (((ip>anchor) & (matchl0>prefixLowest)) && (ip[-1] == matchl0[-1])) { ip--; matchl0--; mLength++; } /* catch up */
goto _match_found;
}
}
if (matchIndexS > prefixLowestIndex) {
if (idxs0 > prefixLowestIndex) {
/* check prefix short match */
if (MEM_read32(match) == MEM_read32(ip)) {
if (MEM_read32(matchs0) == MEM_read32(ip)) {
goto _search_next_long;
}
}
@ -139,18 +155,18 @@ size_t ZSTD_compressBlock_doubleFast_singleSegment_generic(
_search_next_long:
{ size_t const hl3 = ZSTD_hashPtr(ip+1, hBitsL, 8);
U32 const matchIndexL3 = hashLong[hl3];
const BYTE* matchL3 = base + matchIndexL3;
hashLong[hl3] = curr + 1;
{ hl1 = ZSTD_hashPtr(ip+1, hBitsL, 8);
idxl1 = hashLong[hl1];
matchl1 = base + idxl1;
hashLong[hl1] = curr + 1;
/* check prefix long +1 match */
if (matchIndexL3 > prefixLowestIndex) {
if (MEM_read64(matchL3) == MEM_read64(ip+1)) {
mLength = ZSTD_count(ip+9, matchL3+8, iend) + 8;
if (idxl1 > prefixLowestIndex) {
if (MEM_read64(matchl1) == MEM_read64(ip+1)) {
mLength = ZSTD_count(ip+9, matchl1+8, iend) + 8;
ip++;
offset = (U32)(ip-matchL3);
while (((ip>anchor) & (matchL3>prefixLowest)) && (ip[-1] == matchL3[-1])) { ip--; matchL3--; mLength++; } /* catch up */
offset = (U32)(ip-matchl1);
while (((ip>anchor) & (matchl1>prefixLowest)) && (ip[-1] == matchl1[-1])) { ip--; matchl1--; mLength++; } /* catch up */
goto _match_found;
}
}
@ -158,14 +174,14 @@ _search_next_long:
/* if no long +1 match, explore the short match we found */
{
mLength = ZSTD_count(ip+4, match+4, iend) + 4;
offset = (U32)(ip - match);
while (((ip>anchor) & (match>prefixLowest)) && (ip[-1] == match[-1])) { ip--; match--; mLength++; } /* catch up */
mLength = ZSTD_count(ip+4, matchs0+4, iend) + 4;
offset = (U32)(ip - matchs0);
while (((ip>anchor) & (matchs0>prefixLowest)) && (ip[-1] == matchs0[-1])) { ip--; matchs0--; mLength++; } /* catch up */
}
/* fall-through */
_match_found:
_match_found: /* requires ip, offset, mLength */
offset_2 = offset_1;
offset_1 = offset;