Download Computer Org. Lecture 10 Name:_______________ Consider some common ARM Assembly language instructions:

Computer Org.
Lecture 10
Name:_______________
Consider some common ARM Assembly language instructions:
Type of Instruction
Memory Access
ARM Assembly
Language
LDR R1, Mem
STR R1, Mem
Address
ADR R1, Mem
Move
MOV R1, R2
MOV R1, #10
ADD R1, R2, R3
SUB R1, R2, R3
MUL R1, R2, R3
ADD R1, R2, #10
SUB R1, R2, #1
AND R1, R2, R3
ORR R1, R2, R3
BIC R1, R2, R3
ERR R1, R2, R3
CMP R1, R2
Arithmetic Instruction
(reg. or immediate operands
only)
Bit-wise Logical Instructions
Comparison Instructions
(set the condition codes, cc)
Conditional
Branch
Unconditional
Branch
BGT LABEL
BGE LABEL
BLT LABEL
BLE LABEL
BEQ LABEL
BNE LABEL
B LABEL
or BAL LABEL
BL LABEL
Register Transfer Language
Description
R1 b Mem (PC-relative; 32-bit operand)
MembR1 (PC-relative; 32-bit operand)
R1b load address of Mem
R1b R2
R1b 10
R1b R2 + R3
R1b R2 - R3
R1b (R2 x R3)[31:0]
R1b R2 + R3 + C
R1b R2 - 1
R1b R2 and R3
R1b R2 or R3
R1b R2 and (not R3)
R1b R2 xor R3
Sets condition codes on R1 - R2
Branch to LABEL if condition codes are set for >
Branch to LABEL if condition codes are set for >=
Branch to LABEL if condition codes are set for <
Branch to LABEL if condition codes are set for <=
Branch to LABEL if condition codes are set for =
Branch to LABEL if condition codes are set for !=
Always Branch to LABEL
Branch to LABEL and Link (save return value to LR (R14))
1. Translate the following high-level language code segment to ARM assembly language. Use the registers
indicated in the code.
a)
if X < Y then
min = X
else
min = Y
end if
Lecture 10 Page 1
Computer Org.
Lecture 10
Name:_______________
b) for R4 = 0 to 100 by steps of size 10 do
if (R3 < R4) AND (R2 >= 50) then
R2 = R2 + R3
end if
end for
c) while (R8 > 20) do
if (R8 < 100) OR (R8 > 200) then
R7 = R8
R8 = R8 - 10
else
R8 = R8 - R7
end if
R7 = R6 + 4
end while
Lecture 10 Page 2