ADDUW

Add Unsigned Word

ADDUW rd, rs1, rs2

Zero-extends the lower 32 bits of rs1 and adds it to rs2. Useful for 64-bit address calculations with 32-bit unsigned indices.

Details

ADDUW zero-extends the lower 32 bits of rs1 to XLEN bits, adds the result to rs2, and writes to rd. Used for pointer arithmetic with zero-extended 32-bit offsets.

Pseudocode Operation

R[rd] = R[rs2] + zext(R[rs1][31:0]);

Example

ADDUW x10, x11, x12

Encoding

Binary Layout
0000100
31:25
rs2
24:20
rs1
19:15
000
14:12
rd
11:7
0111011
6:0
 
Format R-Type
Opcode 0x3B
Extension Zba

Operands

  • rd
    Destination register (integer)
  • rs1
    Index (32-bit)
  • rs2
    Base