RealView® Compilation Tools Assembler Guide 3.4. Built-in variables and constants

3.4. Built-in variables and constants

Table 3.2 lists the built-in variables defined by the ARM assembler.

Table 3.2. Built-in variables

`{ARCHITECTURE}`	Holds the name of the selected ARM architecture.
`{AREANAME}`	Holds the name of the current AREA.
`{ARMASM_VERSION}`	Holds an integer that increases with each version of `armasm`.
`\|ads$version\|`	Has the same value as `{ARMASM_VERSION}`.
`{CODESIZE}`	Is a synonym for `{CONFIG}`.
`{COMMANDLINE}`	Holds the contents of the command line.
`{CONFIG}`	Has the value `32` if the assembler is assembling ARM code, or `16` if it is assembling Thumb code.
`{CPU}`	Holds the name of the selected cpu. The default is `ARM7TDMI`. If an architecture was specified in the command line `--cpu` option, `{CPU}` holds the value "`Generic ARM`".
`{ENDIAN}`	Has the value `big` if the assembler is in big-endian mode, or `little` if it is in little-endian mode.
`{FPIC}`	Has the value True if `/fpic` is set. The default is False.
`{FPU}`	Holds the name of the selected fpu. The default is `SoftVFP`.
`{INPUTFILE}`	Holds the name of the current source file.
`{INTER}`	Has the value True if `/inter` is set. The default is False.
`{LINENUM}`	Holds an integer indicating the line number in the current source file.
`{OPT}`	Value of the currently-set listing option. The `OPT` directive can be used to save the current listing option, force a change in it, or restore its original value.
`{PC}` or `.`	Address of current instruction.
`{PCSTOREOFFSET}`	Is the offset between the address of the `STR pc,[...]` or `STM Rb,{..., pc}` instruction and the value of pc stored out. This varies depending on the CPU or architecture specified.
`{ROPI}`	Has the value True if `/ropi` is set. The default is False.
`{RWPI}`	Has the value True if `/rwpi` is set. The default is False.
`{VAR}` or `@`	Current value of the storage area location counter.

Built-in variables cannot be set using the SETA, SETL, or SETS directives. They can be used in expressions or conditions, for example:

        IF {ARCHITECTURE} = "4T"

|ads$version| must be all lowercase. The other built-in variables can be uppercase, lowercase, or mixed.

You can use the built-in variable {ARMASM_VERSION} to distinguish between versions of armasm.

The ARM assembler did not have the built-in variable {ARMASM_VERSION} before ADS. If you have to build versions of your code for legacy development tools, you can test for the built-in variable |ads$version|. Use code similar to the following:

    IF :DEF: |ads$version|
      ; code for RVCT or ADS
    ELSE
      ; code for SDT
    ENDIF

Table 3.3 lists the built-in Boolean constants defined by the ARM assembler.

Table 3.3. Built-in Boolean constants

`{FALSE}`	Logical constant false.
`{TRUE}`	Logical constant true.

Copyright © 2002-2007 ARM Limited. All rights reserved.	ARM DUI 0204H
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