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| Linia 1: |
Linia 1: |
| − | '''Session 1, x86 optimization''':
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| − | C/C++: increase the execution speed for the code that reverses the order of the bits composing a 100 M esantioane of unsigned 32-bit (eg. 10111...11 -> 11..11101)
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| − | Expected/Presented techniques:
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| − | Grade 7/10: first implementation ~ 10 seconds
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| − | Grade 8/10: compiler optimized ~ 5 seconds
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| − | Grade 9/10:
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| − | loop unrolling ( > 1s )
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| − | optimizing variables into registers ( > 1s )
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| − | Grade 10: bit-tricks 500 ms
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| − | Grade 10: 256-entry 8-bit table of 1 KB ~ 400 ms
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| − | Grade 10: 16-bit table of 64 k entries (256 KB) ~ 200 ms
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| − | 32-bit table of 4 G entries (16 GB) ~ 66 ms
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