| b2i(by1) * b2i(by2) < ~32768, 0 < b2i(by1), b2i(by2) < 0 ⊦ b2i(by1) * b2i(by2) = s2i(i2s(b2i(by1) * b2i(by2))) |
~32768 = 128 * ~256, b2i(by1) * b2i(by2) < ~32768, 0 < b2i(by1), b2i(by2) < 0 ⊦ b2i(by1) * b2i(by2) = s2i(i2s(b2i(by1) * b2i(by2)))
Used formulas: ~32768 = 128 * ~256