add.uw
Add unsigned word
Performs an XLEN-wide addition between rs2 and the zero-extended least-significant word of rs1.
Decode Variables
Bits<5> xs2 = $encoding[24:20];
Bits<5> xs1 = $encoding[19:15];
Bits<5> xd = $encoding[11:7];Execution
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IDL
-
Sail
if (implemented?(ExtensionName::B) && (misa.B == 1'b0)) {
raise(ExceptionCode::IllegalInstruction, mode(), $encoding);
}
X[xd] = X[xs2] + X[xs1][31:0];{
let rs1_val = X(rs1);
let rs2_val = X(rs2);
let shamt : bits(2) = match op {
RISCV_ADDUW => 0b00,
RISCV_SH1ADDUW => 0b01,
RISCV_SH2ADDUW => 0b10,
RISCV_SH3ADDUW => 0b11
};
let result : xlenbits = (zero_extend(rs1_val[31..0]) << shamt) + rs2_val;
X(rd) = result;
RETIRE_SUCCESS
}