2 use rustc::hir::def_id::DefId;
5 use rustc::ty::{self, Ty, TyCtxt, GenericParamDefKind};
6 use rustc::ty::layout::VariantIdx;
7 use rustc::ty::subst::{Subst, Substs};
8 use rustc::ty::query::Providers;
10 use rustc_data_structures::indexed_vec::{IndexVec, Idx};
12 use rustc_target::spec::abi::Abi;
19 use crate::transform::{
20 add_moves_for_packed_drops, add_call_guards,
21 remove_noop_landing_pads, no_landing_pads, simplify, run_passes
23 use crate::util::elaborate_drops::{self, DropElaborator, DropStyle, DropFlagMode};
24 use crate::util::patch::MirPatch;
26 pub fn provide(providers: &mut Providers<'_>) {
27 providers.mir_shims = make_shim;
30 fn make_shim<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
31 instance: ty::InstanceDef<'tcx>)
34 debug!("make_shim({:?})", instance);
36 let mut result = match instance {
37 ty::InstanceDef::Item(..) =>
38 bug!("item {:?} passed to make_shim", instance),
39 ty::InstanceDef::VtableShim(def_id) => {
43 Adjustment::DerefMove,
44 CallKind::Direct(def_id),
48 ty::InstanceDef::FnPtrShim(def_id, ty) => {
49 let trait_ = tcx.trait_of_item(def_id).unwrap();
50 let adjustment = match tcx.lang_items().fn_trait_kind(trait_) {
51 Some(ty::ClosureKind::FnOnce) => Adjustment::Identity,
52 Some(ty::ClosureKind::FnMut) |
53 Some(ty::ClosureKind::Fn) => Adjustment::Deref,
54 None => bug!("fn pointer {:?} is not an fn", ty)
56 // HACK: we need the "real" argument types for the MIR,
57 // but because our substs are (Self, Args), where Args
58 // is a tuple, we must include the *concrete* argument
59 // types in the MIR. They will be substituted again with
60 // the param-substs, but because they are concrete, this
61 // will not do any harm.
62 let sig = tcx.erase_late_bound_regions(&ty.fn_sig(tcx));
63 let arg_tys = sig.inputs();
73 ty::InstanceDef::Virtual(def_id, _) => {
74 // We are generating a call back to our def-id, which the
75 // codegen backend knows to turn to an actual virtual call.
80 CallKind::Direct(def_id),
84 ty::InstanceDef::ClosureOnceShim { call_once } => {
85 let fn_mut = tcx.lang_items().fn_mut_trait().unwrap();
86 let call_mut = tcx.global_tcx()
87 .associated_items(fn_mut)
88 .find(|it| it.kind == ty::AssociatedKind::Method)
95 CallKind::Direct(call_mut),
99 ty::InstanceDef::DropGlue(def_id, ty) => {
100 build_drop_shim(tcx, def_id, ty)
102 ty::InstanceDef::CloneShim(def_id, ty) => {
103 let name = tcx.item_name(def_id);
105 build_clone_shim(tcx, def_id, ty)
106 } else if name == "clone_from" {
107 debug!("make_shim({:?}: using default trait implementation", instance);
108 return tcx.optimized_mir(def_id);
110 bug!("builtin clone shim {:?} not supported", instance)
113 ty::InstanceDef::Intrinsic(_) => {
114 bug!("creating shims from intrinsics ({:?}) is unsupported", instance)
117 debug!("make_shim({:?}) = untransformed {:?}", instance, result);
119 run_passes(tcx, &mut result, instance, MirPhase::Const, &[
120 &add_moves_for_packed_drops::AddMovesForPackedDrops,
121 &no_landing_pads::NoLandingPads,
122 &remove_noop_landing_pads::RemoveNoopLandingPads,
123 &simplify::SimplifyCfg::new("make_shim"),
124 &add_call_guards::CriticalCallEdges,
127 debug!("make_shim({:?}) = {:?}", instance, result);
129 tcx.alloc_mir(result)
132 #[derive(Copy, Clone, Debug, PartialEq)]
140 #[derive(Copy, Clone, Debug, PartialEq)]
146 fn temp_decl(mutability: Mutability, ty: Ty<'_>, span: Span) -> LocalDecl<'_> {
147 let source_info = SourceInfo { scope: OUTERMOST_SOURCE_SCOPE, span };
151 user_ty: UserTypeProjections::none(),
154 visibility_scope: source_info.scope,
156 is_user_variable: None,
161 fn local_decls_for_sig<'tcx>(sig: &ty::FnSig<'tcx>, span: Span)
162 -> IndexVec<Local, LocalDecl<'tcx>>
164 iter::once(temp_decl(Mutability::Mut, sig.output(), span))
165 .chain(sig.inputs().iter().map(
166 |ity| temp_decl(Mutability::Not, ity, span)))
170 fn build_drop_shim<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
172 ty: Option<Ty<'tcx>>)
175 debug!("build_drop_shim(def_id={:?}, ty={:?})", def_id, ty);
177 // Check if this is a generator, if so, return the drop glue for it
178 if let Some(&ty::TyS { sty: ty::Generator(gen_def_id, substs, _), .. }) = ty {
179 let mir = &**tcx.optimized_mir(gen_def_id).generator_drop.as_ref().unwrap();
180 return mir.subst(tcx, substs.substs);
183 let substs = if let Some(ty) = ty {
184 tcx.intern_substs(&[ty.into()])
186 Substs::identity_for_item(tcx, def_id)
188 let sig = tcx.fn_sig(def_id).subst(tcx, substs);
189 let sig = tcx.erase_late_bound_regions(&sig);
190 let span = tcx.def_span(def_id);
192 let source_info = SourceInfo { span, scope: OUTERMOST_SOURCE_SCOPE };
194 let return_block = BasicBlock::new(1);
195 let mut blocks = IndexVec::with_capacity(2);
196 let block = |blocks: &mut IndexVec<_, _>, kind| {
197 blocks.push(BasicBlockData {
199 terminator: Some(Terminator { source_info, kind }),
203 block(&mut blocks, TerminatorKind::Goto { target: return_block });
204 block(&mut blocks, TerminatorKind::Return);
206 let mut mir = Mir::new(
208 IndexVec::from_elem_n(
209 SourceScopeData { span: span, parent_scope: None }, 1
211 ClearCrossCrate::Clear,
214 local_decls_for_sig(&sig, span),
222 if let Some(..) = ty {
223 // The first argument (index 0), but add 1 for the return value.
224 let dropee_ptr = Place::Local(Local::new(1+0));
225 if tcx.sess.opts.debugging_opts.mir_emit_retag {
226 // Function arguments should be retagged, and we make this one raw.
227 mir.basic_blocks_mut()[START_BLOCK].statements.insert(0, Statement {
229 kind: StatementKind::Retag(RetagKind::Raw, dropee_ptr.clone()),
233 let param_env = tcx.param_env(def_id).with_reveal_all();
234 let mut elaborator = DropShimElaborator {
236 patch: MirPatch::new(&mir),
240 let dropee = dropee_ptr.deref();
241 let resume_block = elaborator.patch.resume_block();
242 elaborate_drops::elaborate_drop(
248 elaborate_drops::Unwind::To(resume_block),
253 patch.apply(&mut mir);
259 pub struct DropShimElaborator<'a, 'tcx: 'a> {
260 pub mir: &'a Mir<'tcx>,
261 pub patch: MirPatch<'tcx>,
262 pub tcx: TyCtxt<'a, 'tcx, 'tcx>,
263 pub param_env: ty::ParamEnv<'tcx>,
266 impl<'a, 'tcx> fmt::Debug for DropShimElaborator<'a, 'tcx> {
267 fn fmt(&self, _f: &mut fmt::Formatter<'_>) -> Result<(), fmt::Error> {
272 impl<'a, 'tcx> DropElaborator<'a, 'tcx> for DropShimElaborator<'a, 'tcx> {
275 fn patch(&mut self) -> &mut MirPatch<'tcx> { &mut self.patch }
276 fn mir(&self) -> &'a Mir<'tcx> { self.mir }
277 fn tcx(&self) -> TyCtxt<'a, 'tcx, 'tcx> { self.tcx }
278 fn param_env(&self) -> ty::ParamEnv<'tcx> { self.param_env }
280 fn drop_style(&self, _path: Self::Path, mode: DropFlagMode) -> DropStyle {
281 if let DropFlagMode::Shallow = mode {
288 fn get_drop_flag(&mut self, _path: Self::Path) -> Option<Operand<'tcx>> {
292 fn clear_drop_flag(&mut self, _location: Location, _path: Self::Path, _mode: DropFlagMode) {
295 fn field_subpath(&self, _path: Self::Path, _field: Field) -> Option<Self::Path> {
298 fn deref_subpath(&self, _path: Self::Path) -> Option<Self::Path> {
301 fn downcast_subpath(&self, _path: Self::Path, _variant: VariantIdx) -> Option<Self::Path> {
304 fn array_subpath(&self, _path: Self::Path, _index: u32, _size: u32) -> Option<Self::Path> {
309 /// Builds a `Clone::clone` shim for `self_ty`. Here, `def_id` is `Clone::clone`.
310 fn build_clone_shim<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
315 debug!("build_clone_shim(def_id={:?})", def_id);
317 let mut builder = CloneShimBuilder::new(tcx, def_id, self_ty);
318 let is_copy = self_ty.is_copy_modulo_regions(tcx, tcx.param_env(def_id), builder.span);
320 let dest = Place::Local(RETURN_PLACE);
321 let src = Place::Local(Local::new(1+0)).deref();
324 _ if is_copy => builder.copy_shim(),
325 ty::Array(ty, len) => {
326 let len = len.unwrap_usize(tcx);
327 builder.array_shim(dest, src, ty, len)
329 ty::Closure(def_id, substs) => {
330 builder.tuple_like_shim(
332 substs.upvar_tys(def_id, tcx)
335 ty::Tuple(tys) => builder.tuple_like_shim(dest, src, tys.iter().cloned()),
337 bug!("clone shim for `{:?}` which is not `Copy` and is not an aggregate", self_ty)
344 struct CloneShimBuilder<'a, 'tcx: 'a> {
345 tcx: TyCtxt<'a, 'tcx, 'tcx>,
347 local_decls: IndexVec<Local, LocalDecl<'tcx>>,
348 blocks: IndexVec<BasicBlock, BasicBlockData<'tcx>>,
350 sig: ty::FnSig<'tcx>,
353 impl<'a, 'tcx> CloneShimBuilder<'a, 'tcx> {
354 fn new(tcx: TyCtxt<'a, 'tcx, 'tcx>,
356 self_ty: Ty<'tcx>) -> Self {
357 // we must subst the self_ty because it's
358 // otherwise going to be TySelf and we can't index
359 // or access fields of a Place of type TySelf.
360 let substs = tcx.mk_substs_trait(self_ty, &[]);
361 let sig = tcx.fn_sig(def_id).subst(tcx, substs);
362 let sig = tcx.erase_late_bound_regions(&sig);
363 let span = tcx.def_span(def_id);
368 local_decls: local_decls_for_sig(&sig, span),
369 blocks: IndexVec::new(),
375 fn into_mir(self) -> Mir<'tcx> {
378 IndexVec::from_elem_n(
379 SourceScopeData { span: self.span, parent_scope: None }, 1
381 ClearCrossCrate::Clear,
386 self.sig.inputs().len(),
393 fn source_info(&self) -> SourceInfo {
394 SourceInfo { span: self.span, scope: OUTERMOST_SOURCE_SCOPE }
399 statements: Vec<Statement<'tcx>>,
400 kind: TerminatorKind<'tcx>,
403 let source_info = self.source_info();
404 self.blocks.push(BasicBlockData {
406 terminator: Some(Terminator { source_info, kind }),
411 /// Gives the index of an upcoming BasicBlock, with an offset.
412 /// offset=0 will give you the index of the next BasicBlock,
413 /// offset=1 will give the index of the next-to-next block,
414 /// offset=-1 will give you the index of the last-created block
415 fn block_index_offset(&mut self, offset: usize) -> BasicBlock {
416 BasicBlock::new(self.blocks.len() + offset)
419 fn make_statement(&self, kind: StatementKind<'tcx>) -> Statement<'tcx> {
421 source_info: self.source_info(),
426 fn copy_shim(&mut self) {
427 let rcvr = Place::Local(Local::new(1+0)).deref();
428 let ret_statement = self.make_statement(
429 StatementKind::Assign(
430 Place::Local(RETURN_PLACE),
431 box Rvalue::Use(Operand::Copy(rcvr))
434 self.block(vec![ret_statement], TerminatorKind::Return, false);
437 fn make_place(&mut self, mutability: Mutability, ty: Ty<'tcx>) -> Place<'tcx> {
438 let span = self.span;
440 self.local_decls.push(temp_decl(mutability, ty, span))
454 let substs = Substs::for_item(tcx, self.def_id, |param, _| {
456 GenericParamDefKind::Lifetime => tcx.types.re_erased.into(),
457 GenericParamDefKind::Type {..} => ty.into(),
461 // `func == Clone::clone(&ty) -> ty`
462 let func_ty = tcx.mk_fn_def(self.def_id, substs);
463 let func = Operand::Constant(box Constant {
467 literal: tcx.mk_lazy_const(ty::LazyConst::Evaluated(
468 ty::Const::zero_sized(func_ty),
472 let ref_loc = self.make_place(
474 tcx.mk_ref(tcx.types.re_erased, ty::TypeAndMut {
476 mutbl: hir::Mutability::MutImmutable,
480 // `let ref_loc: &ty = &src;`
481 let statement = self.make_statement(
482 StatementKind::Assign(
484 box Rvalue::Ref(tcx.types.re_erased, BorrowKind::Shared, src)
488 // `let loc = Clone::clone(ref_loc);`
489 self.block(vec![statement], TerminatorKind::Call {
491 args: vec![Operand::Move(ref_loc)],
492 destination: Some((dest, next)),
493 cleanup: Some(cleanup),
502 loop_body: BasicBlock,
503 loop_end: BasicBlock,
508 let cond = self.make_place(Mutability::Mut, tcx.types.bool);
509 let compute_cond = self.make_statement(
510 StatementKind::Assign(
512 box Rvalue::BinaryOp(BinOp::Ne, Operand::Copy(end), Operand::Copy(beg))
516 // `if end != beg { goto loop_body; } else { goto loop_end; }`
519 TerminatorKind::if_(tcx, Operand::Move(cond), loop_body, loop_end),
524 fn make_usize(&self, value: u64) -> Box<Constant<'tcx>> {
527 ty: self.tcx.types.usize,
529 literal: self.tcx.mk_lazy_const(ty::LazyConst::Evaluated(
530 ty::Const::from_usize(self.tcx, value),
535 fn array_shim(&mut self, dest: Place<'tcx>, src: Place<'tcx>, ty: Ty<'tcx>, len: u64) {
537 let span = self.span;
539 let beg = self.local_decls.push(temp_decl(Mutability::Mut, tcx.types.usize, span));
540 let end = self.make_place(Mutability::Not, tcx.types.usize);
543 // `let mut beg = 0;`
548 StatementKind::Assign(
550 box Rvalue::Use(Operand::Constant(self.make_usize(0)))
554 StatementKind::Assign(
556 box Rvalue::Use(Operand::Constant(self.make_usize(len)))
560 self.block(inits, TerminatorKind::Goto { target: BasicBlock::new(1) }, false);
567 self.loop_header(Place::Local(beg), end, BasicBlock::new(2), BasicBlock::new(4), false);
570 // `dest[i] = Clone::clone(src[beg])`;
571 // Goto #3 if ok, #5 if unwinding happens.
572 let dest_field = dest.clone().index(beg);
573 let src_field = src.index(beg);
574 self.make_clone_call(dest_field, src_field, ty, BasicBlock::new(3),
580 let statements = vec![
582 StatementKind::Assign(
584 box Rvalue::BinaryOp(
586 Operand::Copy(Place::Local(beg)),
587 Operand::Constant(self.make_usize(1))
592 self.block(statements, TerminatorKind::Goto { target: BasicBlock::new(1) }, false);
596 self.block(vec![], TerminatorKind::Return, false);
600 // `let mut beg = 0;`
603 let beg = self.local_decls.push(temp_decl(Mutability::Mut, tcx.types.usize, span));
604 let init = self.make_statement(
605 StatementKind::Assign(
607 box Rvalue::Use(Operand::Constant(self.make_usize(0)))
610 self.block(vec![init], TerminatorKind::Goto { target: BasicBlock::new(6) }, true);
612 // BB #6 (cleanup): loop {
617 self.loop_header(Place::Local(beg), Place::Local(end),
618 BasicBlock::new(7), BasicBlock::new(9), true);
621 // `drop(dest[beg])`;
622 self.block(vec![], TerminatorKind::Drop {
623 location: dest.index(beg),
624 target: BasicBlock::new(8),
631 let statement = self.make_statement(
632 StatementKind::Assign(
634 box Rvalue::BinaryOp(
636 Operand::Copy(Place::Local(beg)),
637 Operand::Constant(self.make_usize(1))
641 self.block(vec![statement], TerminatorKind::Goto { target: BasicBlock::new(6) }, true);
644 self.block(vec![], TerminatorKind::Resume, true);
647 fn tuple_like_shim<I>(&mut self, dest: Place<'tcx>,
648 src: Place<'tcx>, tys: I)
649 where I: Iterator<Item = ty::Ty<'tcx>> {
650 let mut previous_field = None;
651 for (i, ity) in tys.enumerate() {
652 let field = Field::new(i);
653 let src_field = src.clone().field(field, ity);
655 let dest_field = dest.clone().field(field, ity);
657 // #(2i + 1) is the cleanup block for the previous clone operation
658 let cleanup_block = self.block_index_offset(1);
659 // #(2i + 2) is the next cloning block
660 // (or the Return terminator if this is the last block)
661 let next_block = self.block_index_offset(2);
664 // `dest.i = Clone::clone(&src.i);`
665 // Goto #(2i + 2) if ok, #(2i + 1) if unwinding happens.
666 self.make_clone_call(
674 // BB #(2i + 1) (cleanup)
675 if let Some((previous_field, previous_cleanup)) = previous_field.take() {
676 // Drop previous field and goto previous cleanup block.
677 self.block(vec![], TerminatorKind::Drop {
678 location: previous_field,
679 target: previous_cleanup,
683 // Nothing to drop, just resume.
684 self.block(vec![], TerminatorKind::Resume, true);
687 previous_field = Some((dest_field, cleanup_block));
690 self.block(vec![], TerminatorKind::Return, false);
694 /// Builds a "call" shim for `def_id`. The shim calls the
695 /// function specified by `call_kind`, first adjusting its first
696 /// argument according to `rcvr_adjustment`.
698 /// If `untuple_args` is a vec of types, the second argument of the
699 /// function will be untupled as these types.
700 fn build_call_shim<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
702 rcvr_adjustment: Adjustment,
704 untuple_args: Option<&[Ty<'tcx>]>)
707 debug!("build_call_shim(def_id={:?}, rcvr_adjustment={:?}, \
708 call_kind={:?}, untuple_args={:?})",
709 def_id, rcvr_adjustment, call_kind, untuple_args);
711 let sig = tcx.fn_sig(def_id);
712 let sig = tcx.erase_late_bound_regions(&sig);
713 let span = tcx.def_span(def_id);
715 debug!("build_call_shim: sig={:?}", sig);
717 let mut local_decls = local_decls_for_sig(&sig, span);
718 let source_info = SourceInfo { span, scope: OUTERMOST_SOURCE_SCOPE };
720 let rcvr_arg = Local::new(1+0);
721 let rcvr_l = Place::Local(rcvr_arg);
722 let mut statements = vec![];
724 let rcvr = match rcvr_adjustment {
725 Adjustment::Identity => Operand::Move(rcvr_l),
726 Adjustment::Deref => Operand::Copy(rcvr_l.deref()),
727 Adjustment::DerefMove => {
728 // fn(Self, ...) -> fn(*mut Self, ...)
729 let arg_ty = local_decls[rcvr_arg].ty;
730 assert!(arg_ty.is_self());
731 local_decls[rcvr_arg].ty = tcx.mk_mut_ptr(arg_ty);
733 Operand::Move(rcvr_l.deref())
735 Adjustment::RefMut => {
736 // let rcvr = &mut rcvr;
737 let ref_rcvr = local_decls.push(temp_decl(
739 tcx.mk_ref(tcx.types.re_erased, ty::TypeAndMut {
741 mutbl: hir::Mutability::MutMutable
745 let borrow_kind = BorrowKind::Mut {
746 allow_two_phase_borrow: false,
748 statements.push(Statement {
750 kind: StatementKind::Assign(
751 Place::Local(ref_rcvr),
752 box Rvalue::Ref(tcx.types.re_erased, borrow_kind, rcvr_l)
755 Operand::Move(Place::Local(ref_rcvr))
759 let (callee, mut args) = match call_kind {
760 CallKind::Indirect => (rcvr, vec![]),
761 CallKind::Direct(def_id) => {
762 let ty = tcx.type_of(def_id);
763 (Operand::Constant(box Constant {
767 literal: tcx.mk_lazy_const(ty::LazyConst::Evaluated(
768 ty::Const::zero_sized(ty)
775 if let Some(untuple_args) = untuple_args {
776 args.extend(untuple_args.iter().enumerate().map(|(i, ity)| {
777 let arg_place = Place::Local(Local::new(1+1));
778 Operand::Move(arg_place.field(Field::new(i), *ity))
781 args.extend((1..sig.inputs().len()).map(|i| {
782 Operand::Move(Place::Local(Local::new(1+i)))
786 let n_blocks = if let Adjustment::RefMut = rcvr_adjustment { 5 } else { 2 };
787 let mut blocks = IndexVec::with_capacity(n_blocks);
788 let block = |blocks: &mut IndexVec<_, _>, statements, kind, is_cleanup| {
789 blocks.push(BasicBlockData {
791 terminator: Some(Terminator { source_info, kind }),
797 block(&mut blocks, statements, TerminatorKind::Call {
800 destination: Some((Place::Local(RETURN_PLACE),
801 BasicBlock::new(1))),
802 cleanup: if let Adjustment::RefMut = rcvr_adjustment {
803 Some(BasicBlock::new(3))
810 if let Adjustment::RefMut = rcvr_adjustment {
811 // BB #1 - drop for Self
812 block(&mut blocks, vec![], TerminatorKind::Drop {
813 location: Place::Local(rcvr_arg),
814 target: BasicBlock::new(2),
819 block(&mut blocks, vec![], TerminatorKind::Return, false);
820 if let Adjustment::RefMut = rcvr_adjustment {
821 // BB #3 - drop if closure panics
822 block(&mut blocks, vec![], TerminatorKind::Drop {
823 location: Place::Local(rcvr_arg),
824 target: BasicBlock::new(4),
829 block(&mut blocks, vec![], TerminatorKind::Resume, true);
832 let mut mir = Mir::new(
834 IndexVec::from_elem_n(
835 SourceScopeData { span: span, parent_scope: None }, 1
837 ClearCrossCrate::Clear,
847 if let Abi::RustCall = sig.abi {
848 mir.spread_arg = Some(Local::new(sig.inputs().len()));
853 pub fn build_adt_ctor<'a, 'gcx, 'tcx>(infcx: &infer::InferCtxt<'a, 'gcx, 'tcx>,
854 ctor_id: ast::NodeId,
855 fields: &[hir::StructField],
860 let gcx = tcx.global_tcx();
861 let def_id = tcx.hir().local_def_id(ctor_id);
862 let param_env = gcx.param_env(def_id);
864 // Normalize the sig.
865 let sig = gcx.fn_sig(def_id)
867 .expect("LBR in ADT constructor signature");
868 let sig = gcx.normalize_erasing_regions(param_env, sig);
870 let (adt_def, substs) = match sig.output().sty {
871 ty::Adt(adt_def, substs) => (adt_def, substs),
872 _ => bug!("unexpected type for ADT ctor {:?}", sig.output())
875 debug!("build_ctor: def_id={:?} sig={:?} fields={:?}", def_id, sig, fields);
877 let local_decls = local_decls_for_sig(&sig, span);
879 let source_info = SourceInfo {
881 scope: OUTERMOST_SOURCE_SCOPE
884 let variant_no = if adt_def.is_enum() {
885 adt_def.variant_index_with_id(def_id)
890 // return = ADT(arg0, arg1, ...); return
891 let start_block = BasicBlockData {
892 statements: vec![Statement {
894 kind: StatementKind::Assign(
895 Place::Local(RETURN_PLACE),
896 box Rvalue::Aggregate(
897 box AggregateKind::Adt(adt_def, variant_no, substs, None, None),
898 (1..sig.inputs().len()+1).map(|i| {
899 Operand::Move(Place::Local(Local::new(i)))
904 terminator: Some(Terminator {
906 kind: TerminatorKind::Return,
912 IndexVec::from_elem_n(start_block, 1),
913 IndexVec::from_elem_n(
914 SourceScopeData { span: span, parent_scope: None }, 1
916 ClearCrossCrate::Clear,