diff options
| -rw-r--r-- | compiler/rustc_middle/src/mir/consts.rs | 30 |
1 files changed, 15 insertions, 15 deletions
diff --git a/compiler/rustc_middle/src/mir/consts.rs b/compiler/rustc_middle/src/mir/consts.rs index 8f63ed757ba..4e429f316e8 100644 --- a/compiler/rustc_middle/src/mir/consts.rs +++ b/compiler/rustc_middle/src/mir/consts.rs @@ -213,10 +213,10 @@ impl<'tcx> Const<'tcx> { pub fn try_to_scalar(self) -> Option<Scalar> { match self { Const::Ty(c) => match c.kind() { - ty::ConstKind::Value(valtree) => match valtree { - ty::ValTree::Leaf(scalar_int) => Some(Scalar::Int(scalar_int)), - ty::ValTree::Branch(_) => None, - }, + ty::ConstKind::Value(valtree) if c.ty().is_primitive() => { + // A valtree of a type where leaves directly represent the scalar const value. + Some(valtree.unwrap_leaf().into()) + } _ => None, }, Const::Val(val, _) => val.try_to_scalar(), @@ -279,7 +279,16 @@ impl<'tcx> Const<'tcx> { tcx: TyCtxt<'tcx>, param_env: ty::ParamEnv<'tcx>, ) -> Option<Scalar> { - self.eval(tcx, param_env, None).ok()?.try_to_scalar() + match self { + Const::Ty(c) if c.ty().is_primitive() => { + // Avoid the `valtree_to_const_val` query. Can only be done on primitive types that + // are valtree leaves, and *not* on references. (References should return the + // pointer here, which valtrees don't represent.) + let val = c.eval(tcx, param_env, None).ok()?; + Some(val.unwrap_leaf().into()) + } + _ => self.eval(tcx, param_env, None).ok()?.try_to_scalar(), + } } #[inline] @@ -288,16 +297,7 @@ impl<'tcx> Const<'tcx> { tcx: TyCtxt<'tcx>, param_env: ty::ParamEnv<'tcx>, ) -> Option<ScalarInt> { - match self { - // If the constant is already evaluated, we shortcut here. - Const::Ty(c) if let ty::ConstKind::Value(valtree) = c.kind() => { - valtree.try_to_scalar_int() - }, - // This is a more general form of the previous case. - _ => { - self.try_eval_scalar(tcx, param_env)?.try_to_int().ok() - }, - } + self.try_eval_scalar(tcx, param_env)?.try_to_int().ok() } #[inline] |