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https://github.com/wren-lang/wren.git
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2a1499b04b
hashBits() is used to generate a hash code from the same 64 bits used to represent a Wren number as a double. When building a map containing a large number of integer keys, it's important for this to do a good job scattering the bits across the 32-bit key space. Alas, it does not. Worse, the benchmark to test this happens to stop just before the performance falls off a cliff, so this was easy to overlook. This replaces it with the hash function V8 uses, which has much better performance across the numeric range.
20 lines
286 B
Lua
20 lines
286 B
Lua
local start = os.clock()
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local map = {}
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for i = 1, 2000000 do
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map[i] = i
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end
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local sum = 0
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for i = 1, 2000000 do
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sum = sum + map[i]
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end
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io.write(string.format("%d\n", sum))
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for i = 1, 2000000 do
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map[i] = nil
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end
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io.write(string.format("elapsed: %.8f\n", os.clock() - start))
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