Auto merge of #109900 - cjgillot:disable-const-prop, r=oli-obk

Only enable ConstProp at mir-opt-level >= 2.

That pass is not responsible for lints any more, so we can restrict it to optimized builds.

This reduces the amount of duplicated const-eval messages.

2 files changed, 1 insertions, 9 deletions

diff --git a/compiler/rustc_mir_transform/src/const_prop.rs b/compiler/rustc_mir_transform/src/const_prop.rs
index 79a9ac7d20c..c0146e3efb0 100644
--- a/compiler/rustc_mir_transform/src/const_prop.rs
+++ b/compiler/rustc_mir_transform/src/const_prop.rs
@@ -54,7 +54,7 @@ pub struct ConstProp;
 
 impl<'tcx> MirPass<'tcx> for ConstProp {
     fn is_enabled(&self, sess: &rustc_session::Session) -> bool {
-        sess.mir_opt_level() >= 1
+        sess.mir_opt_level() >= 2
     }
 
     #[instrument(skip(self, tcx), level = "debug")]
@@ -854,12 +854,6 @@ impl<'tcx> MutVisitor<'tcx> for ConstPropagator<'_, 'tcx> {
         }
     }
 
-    fn visit_constant(&mut self, constant: &mut Constant<'tcx>, location: Location) {
-        trace!("visit_constant: {:?}", constant);
-        self.super_constant(constant, location);
-        self.eval_constant(constant);
-    }
-
     fn visit_assign(
         &mut self,
         place: &mut Place<'tcx>,
diff --git a/compiler/rustc_mir_transform/src/lib.rs b/compiler/rustc_mir_transform/src/lib.rs
index 2e418c1dafc..fc12d423cb0 100644
--- a/compiler/rustc_mir_transform/src/lib.rs
+++ b/compiler/rustc_mir_transform/src/lib.rs
@@ -566,8 +566,6 @@ fn run_optimization_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
             &separate_const_switch::SeparateConstSwitch,
             &simplify::SimplifyLocals::new("before-const-prop"),
             &copy_prop::CopyProp,
-            //
-            // FIXME(#70073): This pass is responsible for both optimization as well as some lints.
             &const_prop::ConstProp,
             &dataflow_const_prop::DataflowConstProp,
             //