Arch86

Opcode	Encoding	16-bit	32-bit	64-bit	Description
`98` `CBW`	`zo`	Valid	Valid	Valid	Sign extend `AL` into `AX`.
Opcode: `98` Mnemonic: `CBW` Encoding: `zo` Validity (16/32/64 bit): valid, valid, valid Sign extend `AL` into `AX`.
`98` `CWDE`	`zo`	Valid	Valid	Valid	Sign extend `AX` into `EAX`.
Opcode: `98` Mnemonic: `CWDE` Encoding: `zo` Validity (16/32/64 bit): valid, valid, valid Sign extend `AX` into `EAX`.
`REX.W 98` `CDQE`	`zo`	N/E	N/E	Valid	Sign extend `EAX` into `RAX`.
Opcode: `REX.W 98` Mnemonic: `CDQE` Encoding: `zo` Validity (16/32/64 bit): N/E, N/E, valid Sign extend `EAX` into `RAX`.

Encoding

Encoding	Operand
`zo`	None

The CBW/CWDE/CDQE instructions sign extend the accumulator to the next larger size.

This instruction is similar to CWD-CDQ-CQO (Sign Extend Accumulator Into rDX), but working only with the accumulator.

public void CBW()
{
    AX = SignExtend(AL);
}

public void CWDE()
{
    EAX = SignExtend(AX);
}

public void CDQE()
{
    RAX = SignExtend(EAX);
}

None.

#UD

#UD

#UD

#UD

#UD