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Add a couple of prefetch in LZMA for a 4%-18% improvement.

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Cleanup some whitespace.
This commit is contained in:
Moinak Ghosh 2014-11-09 22:04:34 +05:30
parent 507e7c75d3
commit cfe2cea544
3 changed files with 12 additions and 3 deletions
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9
lzma/LzFind.c
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@ -33,6 +33,8 @@
#else #else
#include <emmintrin.h> #include <emmintrin.h>
#endif #endif
#define PREFETCH_T0(addr,nrOfBytesAhead) _mm_prefetch(((char *)(addr))+nrOfBytesAhead,_MM_HINT_T0)
#define PREFETCH_FETCH_DIST 64
#endif #endif
#include "LzFind.h" #include "LzFind.h"
@ -405,6 +407,7 @@ UInt32 * GetMatchesSpec1(UInt32 lenLimit, UInt32 curMatch, UInt32 pos, const Byt
} }
{ {
CLzRef *pair = son + ((_cyclicBufferPos - delta + ((delta > _cyclicBufferPos) ? _cyclicBufferSize : 0)) << 1); CLzRef *pair = son + ((_cyclicBufferPos - delta + ((delta > _cyclicBufferPos) ? _cyclicBufferSize : 0)) << 1);
PREFETCH_T0((const char *)pair, 0);
const Byte *pb = cur - delta; const Byte *pb = cur - delta;
UInt32 len = (len0 < len1 ? len0 : len1); UInt32 len = (len0 < len1 ? len0 : len1);
if (pb[len] == cur[len]) if (pb[len] == cur[len])
@ -473,6 +476,9 @@ diff_cont_g:
} }
if (pb[len] < cur[len]) if (pb[len] < cur[len])
{ {
UInt32 llen = (len0 < len ? len0 : len);
if (llen > 0)
PREFETCH_T0((cur - (pos - *(pair + 1))) + llen, PREFETCH_FETCH_DIST);
*ptr1 = curMatch; *ptr1 = curMatch;
ptr1 = pair + 1; ptr1 = pair + 1;
curMatch = *ptr1; curMatch = *ptr1;
@ -480,6 +486,9 @@ diff_cont_g:
} }
else else
{ {
UInt32 llen = (len < len1 ? len : len1);
if (llen > 0)
PREFETCH_T0((cur - (pos - *pair)) + llen, PREFETCH_FETCH_DIST);
*ptr0 = curMatch; *ptr0 = curMatch;
ptr0 = pair; ptr0 = pair;
curMatch = *ptr0; curMatch = *ptr0;