[Bug middle-end/108992] Regression: Branch direction canonicalization leads to pointless tail duplication / CSE/sinking by inverting branch

["nok.raven at gmail dot com" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108992

--- Comment #6 from Nikita Kniazev <nok.raven at gmail dot com> ---
> Did you see this in real code or you just noticed this while looking at code generation?

If you mean do I have any benchmark - unfortunately no. I noticed it for a
while by poking different code to compare Clang codegen to GCC.

> In the first case GCC predicts that the cond is going to be true 66% of the time

The 66% thing is what I also noticed for a while.

> because there is comparison against 0 prediction going in the heurstics.

The duplication happens even if I make cond int and compare with any other
value

void use(int *);
void use2(int *);

void foo(int * p, int cond)
{
    if (cond == 789) {
        use(p);
    }
    use2(p);
}