Conditional branch with flags in ARM Architecture - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to branch if the zero flag is set.

ARM Architecture

B[1] label_zero

Drag options to blanks, or click blank then click option'

AGT

BNE

CEQ

DLT

Attempts:

3 left

💡 Hint

Common Mistakes

Using NE (not equal) instead of EQ.

Using GT or LT which check other flags.

The EQ condition code means "equal" and is used to branch if the zero flag (Z) is set, indicating the previous operation resulted in zero.

2fill in blank

medium

Complete the code to branch if the negative flag is clear.

ARM Architecture

B[1] label_positive

Drag options to blanks, or click blank then click option'

AMI

BPL

CVS

DVC

Attempts:

3 left

💡 Hint

Common Mistakes

Using MI which branches if negative flag is set.

Confusing VS and VC which relate to overflow flag.

The PL condition code means "plus" and branches if the negative flag (N) is clear, indicating a positive or zero result.

3fill in blank

hard

Fix the error in the branch instruction to branch if carry flag is set.

ARM Architecture

B[1] label_carry

Drag options to blanks, or click blank then click option'

ACS

BCC

CNE

DEQ

Attempts:

3 left

💡 Hint

Common Mistakes

Using CC which branches if carry flag is clear.

Using NE or EQ which check zero flag instead.

The CS condition code means "carry set" and branches if the carry flag (C) is set. Using CC means carry clear, which is incorrect here.

4fill in blank

hard

Fill both blanks to branch if the overflow flag is clear and zero flag is set.

ARM Architecture

B[1][2] label_special

Drag options to blanks, or click blank then click option'

AVC

BEQ

CNE

DVS

Attempts:

3 left

💡 Hint

Common Mistakes

Using VS instead of VC for overflow flag.

Using NE instead of EQ for zero flag.

VC means overflow clear, and EQ means zero flag set. Combining them checks both conditions.

5fill in blank

hard

Fill all three blanks to branch if negative flag is set, zero flag clear, and carry flag set.

ARM Architecture

B[1][2][3] label_complex

Drag options to blanks, or click blank then click option'

AMI

BNE

CCS

DPL

Attempts:

3 left

💡 Hint

Common Mistakes

Using PL instead of MI for negative flag.

Using EQ instead of NE for zero flag.

Using CC instead of CS for carry flag.

MI means negative flag set, NE means zero flag clear, and CS means carry flag set. Combining these condition codes checks all three flags.