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c5c7479014
This includes a very simple pseudo-random number generator, which can be used to drive benchmarks. This doesn't include an official benchmark driver other than a trivial test routine that generates the tree. swift -emit-module -emit-library lfsr.swift -o liblfsr.dylib -O3 swift bst.swift -I. -L. -llfsr -O3 This is currently exposing an optimizer bug which will be filed shortly. Swift SVN r17044
30 lines
788 B
Python
30 lines
788 B
Python
# Linear function shift register.
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#
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# This is just to drive benchmarks. I don't make any claim about its
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# strength. According to Wikipedia, it has the maximal period for a
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# 32-bit register.
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class LFSR:
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def __init__(self):
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# set the register to some seed
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self.lfsr = 0xb78978e7
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def shift(self):
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self.lfsr = (self.lfsr >> 1) ^ (-(self.lfsr & 1) & 0xD0000001)
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def randInt(self):
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result = 0
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for i in range(0,32):
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result = (result << 1) | self.lfsr & 1
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self.shift()
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return result
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if __name__ == "__main__":
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import sys, sets
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lfsr = LFSR()
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rands = sets.Set()
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for i in range (0,int(sys.argv[1])):
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r = lfsr.randInt()
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assert r not in rands
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rands.add(r)
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print r
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