Functions that always return

[Michael Hayes]

Is there a mechanism where we tell if a CALL_INSN will always return?

I had always assumed that a libcall would always return but looking in
libgcc2.c, I see that udivmoddi4 may generate a divide by zero
exception.  This puzzles me since I see that a libcall to udivmoddi4
has a REG_EH_REGION note with a value of -1 which I thought indicated
that the call could not throw an exception?

Could someone please clarify the situation.

Thanks, Michael.