Put deaggregated statements after original constant.

compiler/rustc_mir_transform/src/sroa.rs

@@ -318,6 +318,8 @@ impl<'tcx, 'll> MutVisitor<'tcx> for ReplacementVisitor<'tcx, 'll> {
             // ConstProp will pick up the pieces and replace them by actual constants.
             StatementKind::Assign(box (place, Rvalue::Use(Operand::Constant(_)))) => {
                 if let Some(final_locals) = self.replacements.place_fragments(place) {
+                    // Put the deaggregated statements *after* the original one.
+                    let location = location.successor_within_block();
                     for (field, ty, new_local) in final_locals {
                         let rplace = self.tcx.mk_place_field(place, field, ty);
                         let rvalue = Rvalue::Use(Operand::Move(rplace));