[clang] [Clang] Add __has_target_builtin macro (PR #126324)

[Andrew Pinski via cfe-commits]

pinskia wrote:

What is the definition of current target? Is it the current subtarget? Or is it returning true even when NOT using `#pragma GCC target` (or the target attribute) even if the builtin is not work for the subtarget?
This is unrelated to offloading but is similar issue.
With respect to offloading, the same question comes into play for the offload target too.

I am not defintely the wrong person to ask about offloading and `__has_{*}builtin` as I try to stay away from the offloading stuff.


https://github.com/llvm/llvm-project/pull/126324