REV8

Byte Reverse

REV8 rd, rs1

Reverses the order of bytes in a register (Endian swap).

Encoding

Binary Layout

011010111000

31:20

rs1

19:15

101

14:12

rd

11:7

0010011

6:0

 

Format I-Type

Opcode 0x6B805013

Extension Zbb

Operands

• rd
  Destination register (integer)
• rs1
  Source

Example

REV8 x10, x11

// Converts Big-Endian to Little-Endian.

Related

Across architectures

Byte Swap (Endianness Reversal) : how x86, ARM, RISC-V, and PowerISA each do this.

More in Zbb

Reference

View in RISC-V Unprivileged ISA Specification ↗ RISC-V ISA Manual

Description

REV8 reverses the byte order of rs1 (byte-swap / endianness conversion), writing the result to rd.

Operation

R[rd] = Byteswap(R[rs1]);