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##### 9.4.2.3 Relocatable Expression Modifiers

The assembler supports several modifiers when using relocatable addresses in AVR instruction operands. The general syntax is the following:

         modifier(relocatable-expression)

`lo8`
  This modifier allows you to use bits 0 through 7 of an address expression as 8 bit relocatable expression.
`hi8`
  This modifier allows you to use bits 7 through 15 of an address expression as 8 bit relocatable expression. This is useful with, for example, the AVR ldi instruction and lo8 modifier.

  For example

                ldi r26, lo8(sym+10)
                ldi r27, hi8(sym+10)

`hh8`
  This modifier allows you to use bits 16 through 23 of an address expression as 8 bit relocatable expression. Also, can be useful for loading 32 bit constants.
`hlo8`
  Synonym of hh8.
`hhi8`
  This modifier allows you to use bits 24 through 31 of an expression as 8 bit expression. This is useful with, for example, the AVR ldi instruction and lo8, hi8, hlo8, hhi8, modifier.

  For example

                ldi r26, lo8(285774925)
                ldi r27, hi8(285774925)
                ldi r28, hlo8(285774925)
                ldi r29, hhi8(285774925)
                ; r29,r28,r27,r26 = 285774925

`pm_lo8`
  This modifier allows you to use bits 0 through 7 of an address expression as 8 bit relocatable expression. This modifier useful for addressing data or code from Flash/Program memory. The using of pm_lo8 similar to lo8.
`pm_hi8`
  This modifier allows you to use bits 8 through 15 of an address expression as 8 bit relocatable expression. This modifier useful for addressing data or code from Flash/Program memory.
`pm_hh8`
  This modifier allows you to use bits 15 through 23 of an address expression as 8 bit relocatable expression. This modifier useful for addressing data or code from Flash/Program memory.