X68k/Condition

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This is a sub-page of X68k.

・符号なしの表現		[条件成立フラグ状態]
				 X:  N:  Z:  V:  C:

 x<y	HI (High)		 -   -   0:  -   0:	HI:成立
 x≦y	CC (Carry Clear)	 -   -   -   -   0:	CC:成立
 x>y	CS (Carry Set)		 -   -   -   -   1:	CS:成立
 x≧y	LS (Lower or Same)	 -   -   -   -   1:	LS:成立
	LS (Lower or Same)	 -   -   1:  -   -	LS:成立


・符号ありの表現		[条件成立フラグ状態]
				 X:  N:  Z:  V:  C:

 x<y	GT (Greater Than)	 -   0:  0:  0:  -	GT:成立
	GT (Greater Than)	 -   1:  0:  1:  -	GT:成立
 x≦y	GE (Greater or Equal)	 -   0:  -   0:  -	GE:成立
	GE (Greater or Equal)	 -   1:  -   1:  -	GE:成立
 x>y	LT (Less Than)		 -   0:  -   1:  -	LT:成立
	LT (Less Than)		 -   1:  -   0:  -	LT:成立
 x≧y	LE (Less or Equal)	 -   0:  -   1:  -	LE:成立
	LE (Less or Equal)	 -   1:  -   0:  -	LE:成立
	LE (Less or Equal)	 -   -   1:  -   -	LE:成立


・その他の表現			[条件成立フラグ状態]
				 X:  N:  Z:  V:  C:

 x=y	EQ (Equal)		 -   -   1:  -   -	EQ:成立
 x≠y	NE (Not Equal)		 -   -   0:  -   -	NE:成立
	PL (Plus)		 -   0:  -   -   -	PL:成立
	MI (Minus)		 -   1:  -   -   -	MI:成立
	VC (Overflow Clear)	 -   -   -   0:  -	VC:成立
	VS (Overflow Set)	 -   -   -   1:  -	VS:成立
	T  (True)		 -   -   -   -   -	T :成立
	F  (False)		 -   -   -   -   -	F :不成立

==============================================================================

Pattern	Condition (in words)	CC    Formula	Condition
-----	----			--	--	--------
0000	always True		T		 1
0001	always False		F		 0
0010	High			HI	<(u)	!C・!Z
0011	Lower or Same		LS	≧(u)	 C+ Z
0100	Carry Clear		CC	≦(u)	!C
0101	Carry Set		CS	>(u)	 C
0110	Not Equal		NE	≠	!Z
0111	Equal			EQ	=	 Z
1000	Overflow Clear		VC		!V
1001	Overflow Set		VS		 V
1010	Plus			PL		!N
1011	Minus			MI		 N
1100	Greater or Equal	GE	≦(s)	 N・ V+!N・!V
1101	Less Than		LT	>(s)	 N・!V+!N・ V
1110	Greater Than		GT	<(s)	 N・ V・!Z+!N・!V・!Z
1111	Less or Equal		LE	≧(s)	 N・!V+!N・ V+ Z

Note:
	For the greater/lesser comparisons, (u) means unsigned and (s) signed.
        For the Bcc instructions, the bit pattern belonging to the conition
        ($61??) yields BSR, the one belonging to the T condition yields BRA.