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High-Radix Division and Square-Root with Speculation
August 1994 (vol. 43 no. 8)
pp. 919-931

The speed of high-radix digit-recurrence dividers and square-root units is mainly determined by the complexity of the result-digit selection. We present a scheme in which a simpler function speculates the result digit, and, when this speculation is incorrect, a rollback or a partial advance is performed. This results in operations with a shorter cycle time and a variable number of cycles. The scheme can be used in separate division and square-root units, or in a combined one. Several designs were realized and compared in terms of execution time and area. The fastest unit considered is a radix-512 divider with a partial advance of six bits.

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Index Terms:
digital arithmetic; square-root; high-radix division; digit-recurrence dividers; result digit; speculation; execution time; partial advance; digital arithmetic; digit recurrence; variable-time operation.
J. Cortadella, T. Lang, "High-Radix Division and Square-Root with Speculation," IEEE Transactions on Computers, vol. 43, no. 8, pp. 919-931, Aug. 1994, doi:10.1109/12.295854
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