Register‑relative and program‑relative expressions

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3.6.6. Register‑relative and program‑relative expressions

A register‑relative expression evaluates to a named register plus or minus a numeric constant (see MAP).

A program‑relative expression evaluates to the Program Counter (PC), plus or minus a numeric constant. It is normally a label combined with a numeric expression.

Note

The value used in program-relative addresses is:

the address of the instruction following the instruction being executed
OR 0xFFFFFFFC (this makes no difference in ARM code)
plus or minus the numeric constant.

Example

        LDR     r4,=data+4*n    ; n is an assembly‑time variable
        ; code
        MOV     pc,lr
data    DCD     value0
        ; n‑1 DCD directives
        DCD     valuen          ; data+4*n points here
        ; more DCD directives

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