Auto merge of #88965 - fee1-dead:const-drop-1, r=oli-obk

Fast reject for NeedsNonConstDrop

Hopefully fixes the regression in #88558.

I've always wanted to help with the performance of rustc, but it doesn't feel the same when you are fixing a regression caused by your own PR...

r? `@oli-obk`
This commit is contained in:
bors 2021-09-18 00:18:28 +00:00
commit 8e398f5ba7

View File

@ -111,7 +111,17 @@ impl Qualif for NeedsNonConstDrop {
qualifs.needs_drop
}
fn in_any_value_of_ty(cx: &ConstCx<'_, 'tcx>, ty: Ty<'tcx>) -> bool {
fn in_any_value_of_ty(cx: &ConstCx<'_, 'tcx>, mut ty: Ty<'tcx>) -> bool {
// Avoid selecting for simple cases.
match ty::util::needs_drop_components(ty, &cx.tcx.data_layout).as_deref() {
Ok([]) => return false,
Err(ty::util::AlwaysRequiresDrop) => return true,
// If we've got a single component, select with that
// to increase the chance that we hit the selection cache.
Ok([t]) => ty = t,
Ok([..]) => {}
}
let drop_trait = if let Some(did) = cx.tcx.lang_items().drop_trait() {
did
} else {