Node:ARM Directives, Next:ARM Opcodes, Previous:ARM Floating Point, Up:ARM-Dependent

#### ARM Machine Directives

`.align` expression`[,` expression`]`
  This is the generic .align directive. For the ARM however if the first argument is zero (ie no alignment is needed) the assembler will behave as if the argument had been 2 (ie pad to the next four byte boundary). This is for compatability with ARM's own assembler.
``name`.req` register name``
  This creates an alias for register name called name. For example:

                        foo .req r0

`.code [16|32]`
  This directive selects the instruction set being generated. The value 16 selects Thumb, with the value 32 selecting ARM.
`.thumb`
  This performs the same action as .code 16.
`.arm`
  This performs the same action as .code 32.
`.force_thumb`
  This directive forces the selection of Thumb instructions, even if the target processor does not support those instructions
`.thumb_func`
  This directive specifies that the following symbol is the name of a Thumb encoded function. This information is necessary in order to allow the assembler and linker to generate correct code for interworking between Arm and Thumb instructions and should be used even if interworking is not going to be performed. The presence of this directive also implies `.thumb`
`.thumb_set`
  This performs the equivalent of a `.set` directive in that it creates a symbol which is an alias for another symbol (possibly not yet defined). This directive also has the added property in that it marks the aliased symbol as being a thumb function entry point, in the same way that the `.thumb_func` directive does.
`.ltorg`
  This directive causes the current contents of the literal pool to be dumped into the current section (which is assumed to be the .text section) at the current location (aligned to a word boundary).
`.pool`
  This is a synonym for .ltorg.