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RBIT

Reverse bits

This instruction reverses the bit order in a register.

313029282726252423222120191817161514131211109876543210
sf101101011000000000000RnRd
Sopcode2opcode

32-bit encoding

(sf == 0)

RBIT <Wd>, <Wn>

64-bit encoding

(sf == 1)

RBIT <Xd>, <Xn>

Decode (all encodings)

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.

Operation

let operand : bits(datasize) = X{}(n); var result : bits(datasize); for i = 0 to datasize-1 do result[(datasize-1)-i] = operand[i]; end; X{datasize}(d) = result;

Operational information

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


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