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Altera_Forum
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14 years ago

Determining the index of the first 1 bit in a vector

Let's say I have a 64b wire, and I want to efficiently determine the index of the first 1 bit. For example: wire [63:0] sum; wire [5:0] index; assign sum = 64'b0000000111010110....1010...
Altera_Forum's avatar
Altera_Forum
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14 years ago

I think the most efficient solution involves dividing your 64bit vector in halves recursively.

So, ideally you get a minimum combinatorial path log2(64) long.