c.lui
Load Upper Immediate
C.LUI loads the non-zero 6-bit immediate field into bits 17-12 of the destination register, clears the bottom 12 bits, and sign-extends bit 17 into all higher bits of the destination.
C.LUI expands into lui xd, imm.
C.LUI is only valid when xd≠x0 and xd≠x2, and when the immediate is not equal to zero.
The code points with imm=0 are reserved; the remaining code points with xd=x0 are HINTs; and the remaining code points with xd=x2 correspond to the C.ADDI16SP instruction
| This instruction must have data-independent timing when extension Zkt is enabled. |
Decode Variables
signed Bits<18> imm = sext({$encoding[12], $encoding[6:2], 12'd0}, 18);
Bits<5> xd = $encoding[11:7];Execution
if (implemented?(ExtensionName::C) && (CSR[misa].C == 1'b0)) {
raise(ExceptionCode::IllegalInstruction, mode(), $encoding);
}
X[xd] = $signed(imm);