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fix(bits): terminate unsigned multiplication and preserve high-bit products - #2242
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Shubham-Padkonde wants to merge 1 commit into
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Shubham-Padkonde wants to merge 1 commit into
Shubham-Padkonde wants to merge 1 commit into
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multiplyUnsigned(1, 0xffffffff)never returns because the signed right shift keeps extending the high bit. Use a zero-fill shift so every unsigned 32-bit multiplier reaches zero.Accumulate a numerically doubled multiplicand instead of using a signed left shift, which would otherwise return incorrect negative or truncated partial products after fixing termination. For example,
multiplyUnsigned(2, 0xffffffff)now returns 8589934590.Fixes #2232.
Validation: the original high-bit case times out in an isolated 500 ms VM. The fix passes 20,001 comparisons against BigInt products within the safe-integer range, all 178 suites / 593 tests, full coverage, and ESLint. Six committed regressions cover zero, high bits, both operand orders, and products exceeding 32 bits. Results remain JavaScript Numbers, with the usual precision limits beyond safe integers.
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