Method calcHash

src/callTraceStorage.cpp:172–201

Adaptation of MurmurHash64A by Austin Appleby

// Adaptation of MurmurHash64A by Austin Appleby
u64 CallTraceStorage::calcHash(int num_frames, ASGCT_CallFrame* frames) {
    const u64 M = 0xc6a4a7935bd1e995ULL;
    const int R = 47;

    int len = num_frames * sizeof(ASGCT_CallFrame);
    u64 h = len * M;

    const u64* data = (const u64*)frames;
    const u64* end = data + len / 8;

    while (data != end) {
        u64 k = *data++;
        k *= M;
        k ^= k >> R;
        k *= M;
        h ^= k;
        h *= M;
    }

    if (len & 4) {
        h ^= *(u32*)data;
        h *= M;
    }

    h ^= h >> R;
    h *= M;
    h ^= h >> R;

    return h;
}

CallTrace* CallTraceStorage::storeCallTrace(int num_frames, ASGCT_CallFrame* frames) {
    const size_t header_size = sizeof(CallTrace) - sizeof(ASGCT_CallFrame);