34 lines
1013 B
JavaScript
34 lines
1013 B
JavaScript
import { invariant } from '../utils';
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export function ApplyUnsignedRoundingMode(x, r1, r2, unsignedRoundingMode) {
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if (x.eq(r1))
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return r1;
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invariant(r1.lessThan(x) && x.lessThan(r2), "x should be between r1 and r2 but x=".concat(x, ", r1=").concat(r1, ", r2=").concat(r2));
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if (unsignedRoundingMode === 'zero') {
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return r1;
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}
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if (unsignedRoundingMode === 'infinity') {
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return r2;
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}
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var d1 = x.minus(r1);
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var d2 = r2.minus(x);
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if (d1.lessThan(d2)) {
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return r1;
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}
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if (d2.lessThan(d1)) {
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return r2;
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}
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invariant(d1.eq(d2), 'd1 should be equal to d2');
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if (unsignedRoundingMode === 'half-zero') {
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return r1;
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}
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if (unsignedRoundingMode === 'half-infinity') {
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return r2;
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}
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invariant(unsignedRoundingMode === 'half-even', 'unsignedRoundingMode should be half-even');
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var cardinality = r1.div(r2.minus(r1)).mod(2);
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if (cardinality.isZero()) {
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return r1;
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}
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return r2;
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}
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