Q1.ASM

ADDITION :
	

  AREA PROGRAM2,CODE,READONLY
ENTRY
	LDR R1,VALUE1
	LDR R2,VALUE2
	ADD R3,R2,R1
	AREA PROGRAM2,DATA,READONLY
VALUE1 DCD &00000007
VALUE2 DCD &00000002
	END


SUBTRACTION :

	AREA PROGRAM2,CODE,READONLY
ENTRY
	LDR R1,VALUE1
	LDR R2,VALUE2
	SUB R3,R2,R1
	AREA PROGRAM2,DATA,READONLY
VALUE1 DCD &00000002
VALUE2 DCD &00000007
	END


ii) Indirect addressing mode=2

ADDITION :
	AREA PROGRAM,CODE,READONLY
ENTRY
	LDR R1,VALUE1
	LDR R2,[R1]
	LDR R3,VALUE2
	LDR R4,[R3]
	ADD R6,R4,R2
	AREA PROGRAM,DATA,READONLY
VALUE1 DCD &00000500
VALUE2 DCD &00000800
	END
 

SUBTRACTION :
	AREA PROGRAM,CODE,READONLY
ENTRY
	LDR R1,VALUE1
	LDR R2,[R1]
	LDR R3,VALUE2
	LDR R4,[R3]
	SUB R5,R4,R2
	AREA PROGRAM,DATA,READONLY
VALUE1 DCD &00000500
VALUE2 DCD &00000800
	END



iii) Barrel shifter=4

ADDITION USING LSL, LSR, ROR, ASR :
	AREA PROGRAM2,CODE,READONLY
ENTRY
	LDR R1,VALUE1
	ADD R3,R1,R1,LSL #0X01
	ADD R4,R1,R1,LSR #0X01
	ADD R5,R1,R1,ROR #0X01
	ADD R6,R1,R1,ASR #0X01
	AREA PROGRAM2,DATA,READONLY
VALUE1 DCD &00000004
	END	

	Subtraction using LSL
	AREA Program,CODE,READONLY
ENTRY
	LDR R1,val1
	SUBS R2,R1,R1,LSL #1
	AREA PROGRAM,DATA,READONLY
val1 DCD &00000002
	END