29 lines
609 B
JavaScript
29 lines
609 B
JavaScript
import { MASK } from "./config.js";
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/**
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* Hamming weight.
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*
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* Taken from: http://jsperf.com/hamming-weight
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*
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* @internal
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*/
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export function popcount(x) {
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x -= x >> 1 & 0x55555555;
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x = (x & 0x33333333) + (x >> 2 & 0x33333333);
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x = x + (x >> 4) & 0x0f0f0f0f;
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x += x >> 8;
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x += x >> 16;
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return x & 0x7f;
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}
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/** @internal */
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export function hashFragment(shift, h) {
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return h >>> shift & MASK;
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}
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/** @internal */
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export function toBitmap(x) {
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return 1 << x;
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}
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/** @internal */
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export function fromBitmap(bitmap, bit) {
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return popcount(bitmap & bit - 1);
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}
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//# sourceMappingURL=bitwise.js.map
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