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[[bits]]
== `B` Standard Extension for Bit Manipulation, Version 0.0

This chapter is a placeholder for a future standard extension to provide
bit manipulation instructions, including instructions to insert,
extract, and test bit fields, and for rotations, funnel shifts, and bit
and byte permutations.

Although bit manipulation instructions are very effective in some
application domains, particularly when dealing with externally packed
data structures, we excluded them from the base ISAs as they are not
useful in all domains and can add additional complexity or instruction
formats to supply all needed operands.

We anticipate the B extension will be a brownfield encoding within the
base 30-bit instruction space.