REV

Reverse bytes

This instruction reverses the byte order in a register.

This instruction is used by the pseudo-instruction REV64.

31	30	29	28	27	26	25	24	23	22	21	20	19	18	17	16	15	14	13	12	11	10	9	8	7	6	5	4	3	2	1	0
sf	1	0	1	1	0	1	0	1	1	0	0	0	0	0	0	0	0	0	0	1	x	Rn					Rd
		S									opcode2									opc

32-bit encoding

(sf == 0 && opc == 10)

REV <Wd>, <Wn>

64-bit encoding

(sf == 1 && opc == 11)

REV <Xd>, <Xn>

Decode (all encodings)

if opc == '11' && sf == '0' then EndOfDecode(Decode_UNDEF); end; let d : integer{} = UInt(Rd); let n : integer{} = UInt(Rn); let datasize : integer{} = 32 << UInt(sf); let container_size : integer{} = 8 << UInt(opc);

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); let containers : integer = datasize DIV container_size; for c = 0 to containers-1 do let container : bits(container_size) = operand[c*:container_size]; result[c*:container_size] = Reverse{container_size}(container, 8); 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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