Difference between revisions of "Count Instruction Extension"
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Latest revision as of 18:25, 29 August 2019
Initially implemented in the EV67 processor, the Count Instruction Extension adds three instructions to count bits.
Added Instructions
Mnemonic | Description |
---|---|
ctlz | Count Leading Zeros |
ctpop | Count Population (Count number of 1's) |
cttz | Count Trailing Zeros |
Determining Presence
To determine the presence of CIX, use the amask instruction.
Latency and Slotting
The CIX instructions are slotted U0 and have a latency of 3 cycles. [1].