RBIT

Reverse bits

This instruction reverses the bit order in a register.

313029282726252423222120191817161514131211109876543210
sf101101011000000000000RnRd
Sopcode2opcode

Encoding for the 32-bit variant

Applies when (sf == 0)

RBIT <Wd>, <Wn>

Encoding for the 64-bit variant

Applies when (sf == 1)

RBIT <Xd>, <Xn>

Decode for all variants of this encoding

let d : integer{} = UInt(Rd); let n : integer{} = UInt(Rn); let datasize : integer{} = 32 << UInt(sf);

Assembler Symbols

<Wd>

Is the 32-bit name of the general-purpose destination register, encoded in the "Rd" field.

<Wn>

Is the 32-bit name of the general-purpose source register, encoded in the "Rn" field.

<Xd>

Is the 64-bit name of the general-purpose destination register, encoded in the "Rd" field.

<Xn>

Is the 64-bit name of the general-purpose source register, encoded in the "Rn" field.

Operational information

This instruction is a data-independent-time instruction as described in About PSTATE.DIT.


2026-03_rel 2026-03-26 20:48:11

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