On Wed, 24 Jan 2024 18:48:34 GMT, Aleksey Shipilev <sh...@openjdk.org> wrote:
>> @dholmes-ora Indeed it's a compiler magic, albeit not really weird. While >> the method execution only receives the evaluated value of `expr`, the method >> compilation has the expression in its original form. As a result, it can >> determine the result based on this information. > > It is still weird to talk about expressions at this level. We really check if > the value is constant, like the method name suggests now. Yes, this > implicitly tests that the expression that produced that value is fully > constant-folded. But that's a detail that we do not need to capture here. > Let's rename `expr` -> `val`, and tighten up the javadoc for the method to > mention we only test the constness of the final value. I agree. All values are produced by evaluating expressions. In this case we want to query whether a value produced by the compiler evaluating its expression is a constant value (inputs to the expression are constants and the expression had no material side-effects). Meaning if the method returns true then we could use that knowledge in subsequent expressions that may also produce constants or some specific behavior. ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/17527#discussion_r1465449454
