adr.w

Form PC-relative Address (Wide)

ADR.W <Rd>, <label>

Thumb-2 32-bit ADR.

Pseudocode Operation

offset ← expand_12bit_imm(i : imm3 : imm8)
Rd ← Align(PC, 4) + offset

Example

ADR.W r0, label

Encoding

Binary Layout

11110

31:27

i

26

10

25:24

0

23

0

22

0

21

0

20

1111

19:16

0

15

imm3

14:12

Rd

11:8

imm8

7:0

 

Format Thumb Data Proc

Opcode 0xF20F0000

Extension T32 (Thumb2)

Operands

• Rd
  Destination general-purpose register
• label
  Label

Related

More in T32 (Thumb2)

Reference

View in Arm A64 ISA Reference ↗ Arm AArch32 ISA

Instruction Forms

Encoding	Instruction		ISA		Bit pattern
0x028F0000	ADR{<c>}{<q>} <Rd>, <label>		A32		cond | 0010 | 100 | 0 | 1111 | Rd | imm12
0x024F0000	ADR{<c>}{<q>} <Rd>, <label>		A32		cond | 0010 | 010 | 0 | 1111 | Rd | imm12
0xA000	ADR{<c>}{<q>} <Rd>, <label>		T32		1010 | 0 | Rd | imm8
0xF2AF0000	ADR{<c>}{<q>} <Rd>, <label>		T32		11110 | i | 10 | 1 | 0 | 1 | 0 | 1111 | 0 | imm3 | Rd | imm8
0xF20F0000	ADR{<c>}.W <Rd>, <label>		T32		11110 | i | 10 | 0 | 0 | 0 | 0 | 1111 | 0 | imm3 | Rd | imm8

Description

Form PC-relative address adds an immediate value to the PC value to form a PC-relative address, and writes the result to the destination register.

Operation

if ConditionPassed() then
    EncodingSpecificOperations();
    result = if add then (Align(PC,4) + imm32) else (Align(PC,4) - imm32);
    if d == 15 then          // Can only occur for A32 encodings
        ALUWritePC(result);
    else
        R[d] = result;