In C++20, is there a way to annotate a ternary expression with [[likely]]/[[unlikely]] to hint the compiler which of the two outcomes is more likely?
The following syntax doesn't seem to work
condition ? [[likely]] function1() : function2()
Is there a different syntax to annotate ternary expressions? Or will I have to use an if instead?
Is there a different syntax to annotate ternary expressions?
No, there is no way to annotate a ternary conditional expression with the [[likely]] attribute.
Or will I have to use an if instead?
Yes. Or alternatively, you can omit the attribute.
For what it's worth, it is possible using the GNU extension:
__builtin_expect(!!condition, 1) ? function1() : function2()