Hello! I recently started using gcc-arm and I have a problem with swi. How to call a function with arguments? For example, my swi function: "int sprintf (char * buf, const char * str, ...)" = swi 22 Previously, I used IAR it was possible to do so: # Pragma swi_number = 22 __swi __arm int sprintf (char * buf, const char * str, ...); How it organized on gcc?
You may look into these codes: http://www.siwawi.arubi.uni-kl.de/avr_projects/arm_projects/index_at91.html#at91_gamma http://www.siwawi.arubi.uni-kl.de/avr_projects/arm_projects/lpc2k_bundle_port/index.html They are rather old and I did not check them with the latest versions of the GNU tools but they should at least give an idea. Also browse through the newlib sources, there are implemantations of SWIs to implement semihosting.
Thanks, I already thought of myself today :)
but this method is why it failed to function on 8 arguments, such as the transfer goes through the stack, but normally does not work. Maybe someone knows a working method? There must be some interface for a swi in gcc ...
why the params are not transferred in this case?
_inline_ void sp(char*dest, char *cst, ...)
{
asm volatile("swi 22");
}
and it works
void sp(char*dest, char *cst, ...)
{
asm volatile("swi 22");
}
In this case, the parameres are transmitted through the stack, but I do
not need. When used inline it fits into the function.
How do I type this, an unspecified number of parameters?
_inline_ void sm(int i, int l)
{
register int p0 asm("r0") = i;
register int p1 asm("r1") = l;
asm ("swi 0x148"::"r"(p0),"r"(p1));
}
_inline_ void sm(int i,...)
Reply
Please log in before posting.