czero.nez

Conditional zero, if condition is nonzero

If rs2 contains a nonzero value, this instruction writes the value zero to rd. Otherwise, this instruction copies the contents of rs1 to rd. This instruction carries a syntactic dependency from both rs1 and rs2 to rd. Furthermore, if the Zkt extension is implemented, this instruction’s timing is independent of the data values in rs1 and rs2.

Assembly format

czero.nez rd, rs1, rs2

Decode Variables

Bits<5> rs2 = $encoding[24:20];
Bits<5> rs1 = $encoding[19:15];
Bits<5> rd = $encoding[11:7];

Execution

IDL
Sail

X[rd] = (X[rs2] != 0) ? 0 : X[rs1];

{
  let value = X(rs1);
  let condition = X(rs2);
  let result : xlenbits = if (condition != zeros()) then zeros()
						    else value;
  X(rd) = result;
  RETIRE_SUCCESS
}

Encoding

Defining extension

Zicond, version >= Zicond@1.0.0

Access

M	HS	U	VS	VU
Always	Always	Always	Always	Always

Always

Containing profiles

Mandatory: RVA23M64, RVA23S64, RVA23U64, RVB23M64, RVB23S64, RVB23U64
Optional: