i was starting to play with 64Bit coding weeks ago and could collect some
experince of my engine Homer. I don't know if it works for you or if it helps
you.
First i was reading a lot of stuff in the web about 64Bit coding and made my own
tries. I think the keypoint to become a high performance 64Bit programming are
the integer registers and how we should use this with a effective utilization.
I have a lot of tables and tables-lookup in my engine. My idea is here to go in
direction 64Bit. In the example code i have tables where i performed a bit AND
operation.
Standard 32Bit:
- Code: Select all
int a1[2048];
int a2[2048];
int a3[2048];
for (int i = 0; i < 2048; ++i)
a3[i] = a1[i] & a2[i];
Changing here int to long long (unsigned __int64) brings a lot of speedup in
64Bit:
pure 64Bit:
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long long a1[1024];
long long a2[1024];
long long a3[1024];
for (int i = 0; i < 1024; ++i)
a3[i] = a1[i] & a2[i];
I don't changes the total size of the bit set block, mostly i don't need so much
space but here is the speed more importend
I think there is allso a way for bit-counting stuff. But i'm testing currently
Best,
Daniel
