To help better understand the flaw, we have attached a brief introduction to the SRT division technique.
The SRT divide algorithm can basically be described in steps as:
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Sample the most significant digits of the divisor and dividend.
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Use the samples as indexes into a lookup table to get a guess of the next quotient digits. (in this case the quotient guess can be -2, -1, 0, +1, +2).
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Multiply the divisor by the quotient guess and subtract it from dividend (Note that this is an addition if the quotient guess was negative).
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Save the quotient digits in the least significant digits of a quotient register.
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Shift the remainder left by 2 and shift the quotient registers left by 2 (i.e. radix 4)
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Sample the most significant digits of the new shifted partial remainder.
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Go to step 2 unless you have generated enough significant quotient digits.
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Generate the binary quotient by assembling the values in the quotient register.
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If the last partial remainder was negative then adjust the quotient by subtracting the value.