Someone asked me a simple but classical question:
What is better:
This: if (some_syscall() < 0) {
....
}
Or this: if (some_syscall() == -1) {
....
}
For some system calls (e.g. lseek(2)) one does not have the luxury of
choice (because negative results aren't necessarily erroneous) but for
most others it is only a matter of taste and both are "right"; so I
answered "since in the first case cc(1) will generate jge
instruction and in the second jne it depends on what is faster: jge or
jne".
But what *is* faster? I don't know. And Intel's website doesn't
immediately face one with something useful, such as a table of timings of
their instructions or detailed specs of some future generation
processors but instead greets one with tons of useless b.s. :)
Any pointers?
Regards,
Tigran.
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