Datasheet

ARM Compiler Reference

__pure void (*h(void))(void); /* declares 'h' as a (pure?)

function that returns a pointer to a (pure?) function. It is

ambiguous which of the two function types is pure. */

void (*h1(void) __pure)(void); /* 'h1' is a pure function

returning a pointer to a (normal) function */

__softfp

This asserts that a function uses software floating-point linkage. Calls to

the function pass floating-point arguments in integer registers. If the

result is a floating-point value, the value is returned in integer registers.

This duplicates the behavior of compilation targeting software

floating-point.

This keyword allows an identical library to be used by sources compiled

to use hardware and software floating-point.

__swi

This declares a SWI function taking up to four integer-like arguments and

returning up to four results in a

value_in_regs

structure. This causes

function invocations to be compiled inline as an ATPCS compliant SWI

that behaves similarly to a normal call to a function.

For a SWI returning no results use:

void __swi(swi_num) swi_name(int arg1,…, int argn);

For example:

void __swi(42) terminate_proc(int procnum);

For a SWI returning one result, use:

int __swi(swi_num) swi_name(int arg1,…, int argn);

For a SWI returning more than 1 result use:

typedef struct res_type { int res1,…,resn;} res_type;

res_type __value_in_regs __swi(swi_num) swi_name(

int arg1,…,int argn);

The

__value_in_regs

qualifier is used to specify that a small structure of

up to four words (16 bytes) is returned in registers, rather than by the

usual structure-passing mechanism defined in the ATPCS.

See the chapter on Handling Processor Exceptions in the ADS Developer

Guide for detailed information.

__swi_indirect

This passes an operation code to the SWI handler in r12:

int __swi_indirect(swi_num)

swi_name(int real_num,

int arg1, … argn);

where:

swi_num

Is the SWI number used in the SWI instruction.