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9.1.3.3 Relocations

Relocations for ‘MOVZ’ and ‘MOVK’ instructions can be generated by prefixing the label with ‘#:abs_g2:’ etc. For example to load the 48-bit absolute address of foo into x0:

             movz x0, #:abs_g2:foo		// bits 32-47, overflow check
             movk x0, #:abs_g1_nc:foo	// bits 16-31, no overflow check
             movk x0, #:abs_g0_nc:foo	// bits  0-15, no overflow check

Relocations for ‘ADRP’, and ‘ADD’, ‘LDR’ or ‘STR’ instructions can be generated by prefixing the label with ‘:pg_hi21:’ and ‘#:lo12:’ respectively.

For example to use 33-bit (+/-4GB) pc-relative addressing to load the address of foo into x0:

             adrp x0, :pg_hi21:foo
             add  x0, x0, #:lo12:foo

Or to load the value of foo into x0:

             adrp x0, :pg_hi21:foo
             ldr  x0, [x0, #:lo12:foo]

Note that ‘:pg_hi21:’ is optional.

             adrp x0, foo

is equivalent to

             adrp x0, :pg_hi21:foo