.::Program Manipulation Instructions::.

CALL operand

• calls a subroutine

RET/RETN/RETF (operand)

• returns from a subroutine
• also has near and far returns

INT/INTO (interrupt number)

• calls an interrupt routine
• INTO causes a software breakpoint if overflow flag is set

IRET

• special form of RET
• must be used for an INT/INTO call so that flags are popped

UNCONDITIONAL JUMP

• JMP target

CONDITIONAL JUMP

• Jxxx target
  • Test flags - JC / JNC / JZ / JNZ / JS / JNS / JO / JNO / JP / JPE / JNP / JPO
  • Unsigned comparison - JA / JNBE / JAE / JNB / JB / JNAE / JBE / JNA / JE / JNE
  • Signed comparison - JG / JNLE / JGE / JNL / JL / JNGE / JLE / JNG / JE / JNE

JCXZ/JECXZ target

• jump if CX/ECX is zero

LOOP target

• decrements CX
• branches to target if CX is not zero

LOOPE/LOOPZ target

• loop while equal/zero
• same as LOOP but branches if CX not zero and zero flag is set

LOOPNE/LOOPNZ target

• like LOOPE/LOOPZ but branches if CX is not zero and zero flag is clear