Motorola MC68030 - Condition Code Computation

Instruction Set Summary
MOTOROLA MC68030 USER’S MANUAL 3-15
3.3.1 Condition Code Computation
Most operations take a source operand and a destination operand, compute, and store the
result in the destination location. Single-operand operations take a destination operand,
compute, and store the result in the destination location. Table 3–12 lists each instruction
and how it affects the condition code bits.
Table 3-12. Condition Code Computations (Sheet 1 of 2)
Operations X N Z V C Special Definition
ABCD * U ? U ? C =-Decimal Carry
Z =-Z Λ Rm Λ . . . Λ R0
ADD, ADDI, ADDQ * * * ? ? V = Sm Λ Dm Λ Rm V Sm Λ Dm Λ Rm
C = Sm Λ Dm V Rm Λ Dm V Sm Λ Rm
ADDX * * ? ? ? V = Sm Λ Dm Λ Rm V Sm Λ Dm Λ Rm
C = Sm Λ Dm V Rm Λ Dm V Sm Λ Rm
Z = Z Λ Rm
Λ . . . Λ R0
AND, ANDI, EOR, EORI,
MOVEQ, MOVE, OR, ORI
CLR, EXT, NOT, TAS, TST
— * * 0 0
CHK — * U U U
CHK2, CMP2 — U ? U ? Z = (R = LB) V (R = UB)
C = (LB < = UB) Λ (IR < LB) V (R > UB))
V = (UB <LB) Λ (R >UB) Λ (R <LB)
SUB, SUBI, SUBQ * * * ? ? V = Sm Λ Dm
Λ Rm V Sm Λ Dm Λ Rm
C = Sm Λ Dm V Rm Λ Dm V Sm Λ Rm
SUBX * * ? ? ? V = Sm Λ Dm Λ Rm V Sm Λ Dm Λ Rm
C = Sm Λ Dm V Rm Λ Dm V Sm Λ Rm
Z = Z Λ Rm Λ . . . Λ R0
CAS, CAS2, CMP, CMPI,
CMPM
— * * ? ? V = Sm Λ Dm Λ Rm V Sm Λ Dm Λ Rm
C = Sm Λ Dm V Rm Λ Dm V Sm Λ Rm
DIVS, DUVI — * * ? 0 V = Division Overflow
MULS, MULU — * * ? 0 V = Multiplication Overflow
SBCD, NBCD * U U ? C = Decimal Borrow
Z = Z Λ Rm
Λ . . . Λ R0
NEG * * * ? ? V = Dm Λ Rm
C = Dm V Rm
NEGX * * ? ? ? V = Dm Λ Rm
C = Dm V Rm
Z = Z Λ Rm Λ . . . Λ R0