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feat: always use 64-bit hash computation #46

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feat: always use 64-bit hash computation #46

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2 changes: 1 addition & 1 deletion libfsst.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -467,7 +467,7 @@ vector<const u8*> makeSample(u8* sampleBuf, const u8* strIn[], const size_t **le
for(size_t i=0; i<nlines; i++)
sample.push_back(strIn[i]);
} else {
size_t sampleRnd = FSST_HASH(4637947);
u64 sampleRnd = FSST_HASH(4637947);
const u8* sampleLim = sampleBuf + FSST_SAMPLETARGET;
size_t *sampleLen = new size_t[nlines + FSST_SAMPLEMAXSZ/FSST_SAMPLELINE];
*lenRef = sampleLen;
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4 changes: 2 additions & 2 deletions libfsst.hpp
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Expand Up @@ -116,10 +116,10 @@ struct Symbol {
u16 first2() const { assert( length() >= 2); return 0xFFFF & load_num(); }

#define FSST_HASH_LOG2SIZE 10
#define FSST_HASH_PRIME 2971215073LL
#define FSST_HASH_PRIME 2971215073ULL
#define FSST_SHIFT 15
#define FSST_HASH(w) (((w)*FSST_HASH_PRIME)^(((w)*FSST_HASH_PRIME)>>FSST_SHIFT))
size_t hash() const { size_t v = 0xFFFFFF & load_num(); return FSST_HASH(v); } // hash on the next 3 bytes
u64 hash() const { u64 v = 0xFFFFFF & load_num(); return FSST_HASH(v); } // hash on the next 3 bytes
};

// Symbol that can be put in a queue, ordered on gain
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