Narrowing legalize some more bitops

cranelift/codegen/meta/src/shared/legalize.rs

@@ -207,7 +207,7 @@ pub(crate) fn define(insts: &InstructionGroup, imm: &Immediates) -> TransformGro
         ],
     );
 
-    for &bin_op in &[band, bor, bxor] {
+    for &bin_op in &[band, bor, bxor, band_not, bor_not, bxor_not] {
         narrow.legalize(
             def!(a = bin_op(x, y)),
             vec![
@@ -220,6 +220,16 @@ pub(crate) fn define(insts: &InstructionGroup, imm: &Immediates) -> TransformGro
         );
     }
 
+    narrow.legalize(
+        def!(a = bnot(x)),
+        vec![
+            def!((xl, xh) = isplit(x)),
+            def!(al = bnot(xl)),
+            def!(ah = bnot(xh)),
+            def!(a = iconcat(al, ah)),
+        ],
+    );
+
     narrow.legalize(
         def!(a = select(c, x, y)),
         vec![