2012-02-21  Labutin Ivan  <barracuda72@bk.ru>

	* gcc/config/arm/arm.c: Added support for __attribute__ ((swi(x))).
          With this, you can write function prototype:
            int some_sys_call (int, char*) __attribute__ ((swi(0x15)));
          Now, if you call it:
            a = some_sys_call (5, "test");
          it will produce following assembler output:
            ...
            MOV R1, #test_adr 
            MOV R0, #5
            SWI 0x15
            ...
          This is an analogue of 
            #pragma swi_number=0x15 int some_sys_call (int, char *);
          or
            __swi(0x15) int some_sys_call (int, char*);
          in other ARM-targeted compiliers.
        * gcc/config/arm.md: Likewise.
        * gcc/config/arm-protos.h: Likewise.