Clear Direction Flag

Encoding

EncodingOperand
zoNone

Description

The CLD instruction clears EFLAGS.DF (the direction flag).

Operation

public void CLD()
{
    EFLAGS.DF = 0;
}

Flags Affected

CF (carry flag)
Unmodified.
PF (parity flag)
Unmodified.
AF (auxiliary flag)
Unmodified.
ZF (zero flag)
Unmodified.
SF (sign flag)
Unmodified.
DF (direction flag)
Cleared.
OF (overflow flag)
Unmodified.

Exceptions

Real-Address Mode

#UD
  • If the
  • LOCK
  • prefix is used.

Virtual-8086 Mode

#UD
  • If the
  • LOCK
  • prefix is used.

Protected Mode

#UD
  • If the
  • LOCK
  • prefix is used.

Compatibility Mode

#UD
  • If the
  • LOCK
  • prefix is used.

Long Mode

#UD
  • If the
  • LOCK
  • prefix is used.