ARM assembler instructions

The ARM assembler supports the following ARM Thumb instructions:

Operation   Example Flags Action Notes
Move

Immediate

Low to Low

Any to Any

($mov 'r0 23)

($mov 'r0 'r1)

($mov 'r10 'r1)

NZ

NZ

r0 = 23

r0 = r1

r10 = r1

Range 0 to 255
Add

Immediate

All Low

With carry

Immediate to SP

Form address from SP

Any to Any

($add 'r0 'r1 2)

($add 'r0 'r1 'r2)

($adc 'r0 'r1)

($add 'sp 8)

($add 'r0 'sp 4)

($add 'r10 'r11)

NZCV

NZCV

NZCV

r0 = r1 + 2

r0 = r1 + r2

r0 = r0 + r1 + C

sp = sp + 8

r0 = sp + 4

r10 = r10 + r11

Range 0 to 7

All Low.

All Low.

Range 0 to 508 (word aligned)

Range 0 to 1020 (word aligned)

Not Low to Low

Subtract

Immediate

All Low

With carry

Immediate from SP

($sub 'r0 'r1 2)

($sub 'r0 'r1 'r2)

($sbc 'r0 'r1)

($sub 'sp 8)

NZCV

NZCV

NZCV

r0 = r1 - 2

r0 = r1 - r2

r0 = r0 - r1 - NOT C

sp = sp - 8

Range to 7

All Low

Multiply Multiply ($mul 'r0 'r1) NZ?? r0 = r0 * r1 C and V unpredictable
Compare

Any to Any

Immediate

Negative

($cmp r0 r1)

($cmp 'r0 100)

($cmn r0 r1)

NZCV

NZCV

NZCV

Flags: r0 - r1

Flags: r0 - 100

Flags: r0 + r1

 

Range 0 to 255

Logical

AND

EOR

OR

Bit clear

Move NOT

Test bits

($and 'r0 'r1)

($eor 'r0 'r1)

($orr 'r0 'r1)

($bic 'r0 'r1)

($mvn 'r0 'r1)

($tst 'r0 'r1)

NZ

NZ

NZ

NZ

NZ

NZ

r0 = r0 AND r1

r0 = r0 EOR r1

r0 = r0 OR r1

r0 = r0 AND NOTr1

r0 = NOT r1

Flags: r0 AND r1

 

Shift/
rotate

Logical shift left immed.

Logical shift left

Logical shift right immed.

Logical shift right

Arithmetic shift right immed.

Arithmetic shift right

Rotate right

($lsl 'r0 'r1 3)

($lsl 'r0 'r2)

($lsr 'r0 'r1 3)

($lsr 'r0 'r2)

($asr 'r0 'r1 3)

($asr 'r0 'r2)

($ror 'r0 'r2)

NZC*

NZC*

NZC*

NZC

NZC*

NZC

NZC*

r0 = r1 << 3

r0 = r0 << r2[7:0]

r0 = r1 >> 3

r0 = r0 >> r2[7:0]

r0 = r1 ASR 3

r0 = r0 ASR r2[7:0]

r0 = r0 ROR r2[7:0]

Range 0 to 31.

 

Range 0 to 31.

 

Range 0 to 31.

Load

Immed. offset - word

- halfword

- byte

Register offset - word

- halfword

- signed halfword

- byte

- signed byte

PC-relative

SP-relative

($ldr 'r0 '(r1 2))

($ldrh 'r0 '(r1 3))

($ldrb 'r0 '(r1 4))

($ldr 'r0 '(r1 r2))

($ldrh 'r0 '(r1 r2))

($ldrsh 'r0 '(r1 r2))

($ldrb 'r0 '(r1 r2))

($ldrsb 'r0 '(r1 r2))

($ldr 'r0 label)

($ldr 'r0 '(sp 23))

 

r0 = [r1+2]

r0 = 00CD[r1+3]

r0 = 000D[r1+4]

r0 = [r1+r2]

r0 = 00CD[r1+r2]

r0 = XXCD[r1+r2]

r0 = 000D[r1+r2]

r0 = XXXD[r1+r2]

r0 = [label]

r0 = [SP + 23]

Range 0 to 124, multiple of 4.

Range 0 to 62, even.

Range 0 to 31.

 

 

 

 

 

Range PC to PC+1020 word-aligned

Range 0 to 1020, multiple of 4

Store

Immed. offset - word

- halfword

- byte

Register offset - word

- halfword

- byte

SP-relative

($str 'r0 '(r1 5))

($strh 'r0 '(r1 6))

($strb 'r0 '(r1 7))

($str 'r0 '(r1 r2))

($strh 'r0 '(r1 r2))

($strb 'r0 '(r1 r2))

($str 'r0 '(sp 8))

 

[r1+5] = r0

[r1+6] = r0

[r1+7] = r0

[r1+r2] = r0

[r1+r2] = r0

[r1+r2] = r0

[SP+8] = r0

Range 0 to 124, multiple of 4.

Range 0 to 62, even.

Range 0 to 31.

 

 

 

Range 0 to 1020, multiple of 4

Push Push ($push '(r4 r5 lr))   Push registers Any except pc.
Pop Pop ($pop '(r4 r5 pc))   Pop registers Any except lr.
Branch

Conditional branch

Unconditional branch

Long branch with link

Branch and exch.

Branch with link and exch.

Branch with link and exch.

($beq label)

($b label)

($bl label)

($bx 'r0)

($blx label)

($blx 'r0)

 

If cond PC = label

PC = label

PC = label, LR = next

PC = r0

PC = label, LR = next

PC = r0, LR = next

Label within -252 to +258 bytes.

Label within ±2Kbytes.

Label within ±4Mbytes.

 

Label within ±4Mbytes.

Extend

Signed, half to word

Signed, byte to word

Unsigned, half to word

Unsigned, byte to word

($sxth 'r0 'r1)

($sxtb 'r0 'r1)

($uxth 'r0 'r1)

($uxtb 'r0 'r1)

 

ABCD -> XXCD

ABCD -> XXXD

ABCD -> 00CD

ABCD -> 000D

A, B, C, and D are bytes.

X is sign extended.

0 is zero extended.

Reverse

Bytes in words

Bytes in both halves

Bytes in low half, sign extend

($rev 'r0 'r1)

($rev16 'r0 'r1)

($revsh 'r0 'r1)

 

ABCD -> DCBA

ABCD -> BADC

ABCD -> XXDC

A, B, C, and D are bytes.

X is sign extended.

State Not yet implemented.        
No op No operation ($nop)      
Hint Not yet implemented.