PACK

Pack two words into a register

PACK rd, rs1, rs2

Packs the lower halves of rs1 and rs2 into rd.

Encoding

Binary Layout

0000100

31:25

rs2

24:20

rs1

19:15

100

14:12

rd

11:7

0110011

6:0

 

Format R-Type

Opcode 0x08004033

Extension Zbkb

Operands

• rd
  Destination register (integer)
• rs1
  Lower Half
• rs2
  Upper Half

Example

PACK t0, a0, a1

Related

More in Zbkb

Reference

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

Description

Pack two words into a register: Packs the lower halves of rs1 and rs2 into rd. Operation: R[rd] = (R[rs2] << XLEN/2) | (R[rs1] & ((1 << XLEN/2)-1));.

Operation

R[rd] = (R[rs2] << XLEN/2) | (R[rs1] & ((1 << XLEN/2)-1));