[LLVMdev] floating point exceptions in compare instructions
Rafael EspĂndola
rafael.espindola at gmail.com
Fri Oct 13 11:41:53 PDT 2006
> Nope, you want non-trapping instructions. If you use trapping
> instructions, C99 functions like isgreater will not work correctly with
> NAN's.
How do I know when to use a trapping instruction? For example consider
this C function:
------------------------
int f(float a, float b) {
return a <= b;
}
------------------------
gcc uses fcmpes instead of fcmps...
> -Chris
Thanks,
Rafael
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