s3c2410a Samsung Semiconductor, Inc., s3c2410a Datasheet - Page 141

• Manufacturer Part Number: s3c2410a
• Description: 16/32-bit Risc Arm Microprocessor
• Manufacturer: Samsung Semiconductor, Inc.

S3C2410A
INSTRUCTION SET EXAMPLES
The following examples show ways in which the basic ARM920T instructions can combine to give efficient code.
None of these methods saves a great deal of execution time (although they may save some), mostly they just save
code.
USING THE CONDITIONAL INSTRUCTIONS
Using Conditionals for Logical OR
This can be replaced by
Absolute Value
Multiplication by 4, 5 or 6 (Run Time)
Combining Discrete and Range Tests
CMP
BEQ
CMP
BEQ
CMP
CMPNE
BEQ
TEQ
RSBMI
MOV
CMP
ADDCS
ADDHI
TEQ
CMPNE
MOVLS
Rn,#p
Label
Rm,#q
Label
Rn,#p
Rm,#q
Label
Rn,#0
Rn,Rn,#0
Rc,Ra,LSL#2
Rb,#5
Rc,Rc,Ra
Rc,Rc,Ra
Rc,#127
Rc,# " "-1
Rc,# ""
; If Rn=p OR Rm=q THEN GOTO Label.
; If condition not satisfied try other test.
; Test sign
; and 2's complement if necessary.
; Multiply by 4,
; Test value,
; Complete multiply by 5,
; Complete multiply by 6.
; Discrete test,
; Range test
; IF Rc<= "" OR Rc=ASCII(127)
; THEN Rc:= "."
ARM INSTRUCTION SET
3-59