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Booth:
result = multiplier << 1
loop (operand length) times:
if last two bits are 01:
result(upper half) += multiplicand
if last two bits are 10:
result(upper half) += twos_comp(multiplicand)
remove extra bits from result
arithmatic shift result right
result >> 1
Modified booth:
multiplicand(MSB) = multiplicand(second MSB)
result = multiplier << 1
loop (operand length / 2) times:
if last two bits are 001 or 010:
result(upper half) += multiplicand
if last two bits are 011:
result(upper half) += multiplicand * 2
if last two bits are 100:
result(upper half) += twos_comp(multiplicand) * 2
if last two bits are 101 or 110:
result(upper half) += twos_comp(multiplicand)
remove extra bits from result
arithmatic shift result right twice
result >> 1
result(second MSB) = result(MSB)
result(MSB) = 0
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