opt-level >= 4

Author: shamatar

compiler/rustc_mir_transform/src/normalize_array_len.rs

@@ -15,9 +15,9 @@ pub struct NormalizeArrayLen;
 
 impl<'tcx> MirPass<'tcx> for NormalizeArrayLen {
     fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
-        // if tcx.sess.mir_opt_level() < 3 {
-        //     return;
-        // }
+        if tcx.sess.mir_opt_level() < 4 {
+            return;
+        }
 
         // early returns for edge cases of highly unrolled functions
         if body.basic_blocks().len() > MAX_NUM_BLOCKS {

src/test/mir-opt/lower_array_len.rs

@@ -1,4 +1,4 @@
-// compile-flags: -Z mir-opt-level=3
+// compile-flags: -Z mir-opt-level=4
 
 // EMIT_MIR lower_array_len.array_bound.NormalizeArrayLen.diff
 // EMIT_MIR lower_array_len.array_bound.SimplifyLocals.diff