C.ADDIW

Compressed Add Immediate Word

C.ADDIW rd, imm

Adds a signed immediate to a register (32-bit result sign-extended, RV64).

Details

Adds a 6-bit sign-extended immediate to rd (RV64/RV128 only), truncates to 32 bits, sign-extends to 64 bits.

Pseudocode Operation

R[rd] = sext((R[rd] + sext(imm))[31:0]);

Example

C.ADDIW t0, 16

Encoding

Binary Layout
?
31:16
001
15:13
c_imm6hi
12
rd_rs1_n0
11:7
c_imm6lo
6:2
01
1:0
 
Format CI
Opcode 0x00002001
Extension C

Operands

  • rd
    Dest/Src
  • imm
    Signed immediate value