1 files changed, 44 insertions, 0 deletions
diff --git a/compiler/rustc_mir_transform/src/reveal_all.rs b/compiler/rustc_mir_transform/src/reveal_all.rs
new file mode 100644
index 000000000..4919ad400
--- /dev/null
+++ b/compiler/rustc_mir_transform/src/reveal_all.rs
@@ -0,0 +1,44 @@
+//! Normalizes MIR in RevealAll mode.
+
+use crate::MirPass;
+use rustc_middle::mir::visit::*;
+use rustc_middle::mir::*;
+use rustc_middle::ty::{self, Ty, TyCtxt};
+
+pub struct RevealAll;
+
+impl<'tcx> MirPass<'tcx> for RevealAll {
+    fn is_enabled(&self, sess: &rustc_session::Session) -> bool {
+        sess.mir_opt_level() >= 3 || super::inline::Inline.is_enabled(sess)
+    }
+
+    fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
+        // Do not apply this transformation to generators.
+        if body.generator.is_some() {
+            return;
+        }
+
+        let param_env = tcx.param_env_reveal_all_normalized(body.source.def_id());
+        RevealAllVisitor { tcx, param_env }.visit_body(body);
+    }
+}
+
+struct RevealAllVisitor<'tcx> {
+    tcx: TyCtxt<'tcx>,
+    param_env: ty::ParamEnv<'tcx>,
+}
+
+impl<'tcx> MutVisitor<'tcx> for RevealAllVisitor<'tcx> {
+    #[inline]
+    fn tcx(&self) -> TyCtxt<'tcx> {
+        self.tcx
+    }
+
+    #[inline]
+    fn visit_ty(&mut self, ty: &mut Ty<'tcx>, _: TyContext) {
+        // We have to use `try_normalize_erasing_regions` here, since it's
+        // possible that we visit impossible-to-satisfy where clauses here,
+        // see #91745
+        *ty = self.tcx.try_normalize_erasing_regions(self.param_env, *ty).unwrap_or(*ty);
+    }
+}