1 //! A different sort of visitor for walking fn bodies. Unlike the
2 //! normal visitor, which just walks the entire body in one shot, the
3 //! `ExprUseVisitor` determines how expressions are being used.
5 pub use self::ConsumeMode::*;
7 // Export these here so that Clippy can use them.
8 pub use rustc_middle::hir::place::{Place, PlaceBase, PlaceWithHirId, Projection};
10 use rustc_data_structures::fx::FxIndexMap;
12 use rustc_hir::def::Res;
13 use rustc_hir::def_id::LocalDefId;
14 use rustc_hir::PatKind;
15 use rustc_index::vec::Idx;
16 use rustc_infer::infer::InferCtxt;
17 use rustc_middle::hir::place::ProjectionKind;
18 use rustc_middle::mir::FakeReadCause;
19 use rustc_middle::ty::{self, adjustment, TyCtxt};
20 use rustc_target::abi::VariantIdx;
22 use crate::mem_categorization as mc;
24 ///////////////////////////////////////////////////////////////////////////
27 /// This trait defines the callbacks you can expect to receive when
28 /// employing the ExprUseVisitor.
29 pub trait Delegate<'tcx> {
30 // The value found at `place` is either copied or moved, depending
31 // on `mode`. Where `diag_expr_id` is the id used for diagnostics for `place`.
33 // The parameter `diag_expr_id` indicates the HIR id that ought to be used for
34 // diagnostics. Around pattern matching such as `let pat = expr`, the diagnostic
35 // id will be the id of the expression `expr` but the place itself will have
36 // the id of the binding in the pattern `pat`.
39 place_with_id: &PlaceWithHirId<'tcx>,
40 diag_expr_id: hir::HirId,
44 // The value found at `place` is being borrowed with kind `bk`.
45 // `diag_expr_id` is the id used for diagnostics (see `consume` for more details).
48 place_with_id: &PlaceWithHirId<'tcx>,
49 diag_expr_id: hir::HirId,
53 // The path at `assignee_place` is being assigned to.
54 // `diag_expr_id` is the id used for diagnostics (see `consume` for more details).
55 fn mutate(&mut self, assignee_place: &PlaceWithHirId<'tcx>, diag_expr_id: hir::HirId);
57 // The `place` should be a fake read because of specified `cause`.
58 fn fake_read(&mut self, place: Place<'tcx>, cause: FakeReadCause, diag_expr_id: hir::HirId);
61 #[derive(Copy, Clone, PartialEq, Debug)]
62 pub enum ConsumeMode {
63 Copy, // reference to x where x has a type that copies
64 Move, // reference to x where x has a type that moves
67 #[derive(Copy, Clone, PartialEq, Debug)]
71 WriteAndRead, // x += y
74 ///////////////////////////////////////////////////////////////////////////
75 // The ExprUseVisitor type
77 // This is the code that actually walks the tree.
78 pub struct ExprUseVisitor<'a, 'tcx> {
79 mc: mc::MemCategorizationContext<'a, 'tcx>,
80 body_owner: LocalDefId,
81 delegate: &'a mut dyn Delegate<'tcx>,
84 // If the MC results in an error, it's because the type check
85 // failed (or will fail, when the error is uncovered and reported
86 // during writeback). In this case, we just ignore this part of the
89 // Note that this macro appears similar to try!(), but, unlike try!(),
90 // it does not propagate the error.
91 macro_rules! return_if_err {
96 debug!("mc reported err");
103 impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
104 /// Creates the ExprUseVisitor, configuring it with the various options provided:
106 /// - `delegate` -- who receives the callbacks
107 /// - `param_env` --- parameter environment for trait lookups (esp. pertaining to `Copy`)
108 /// - `typeck_results` --- typeck results for the code being analyzed
110 delegate: &'a mut (dyn Delegate<'tcx> + 'a),
111 infcx: &'a InferCtxt<'a, 'tcx>,
112 body_owner: LocalDefId,
113 param_env: ty::ParamEnv<'tcx>,
114 typeck_results: &'a ty::TypeckResults<'tcx>,
117 mc: mc::MemCategorizationContext::new(infcx, param_env, body_owner, typeck_results),
123 pub fn consume_body(&mut self, body: &hir::Body<'_>) {
124 debug!("consume_body(body={:?})", body);
126 for param in body.params {
127 let param_ty = return_if_err!(self.mc.pat_ty_adjusted(¶m.pat));
128 debug!("consume_body: param_ty = {:?}", param_ty);
130 let param_place = self.mc.cat_rvalue(param.hir_id, param.pat.span, param_ty);
132 self.walk_irrefutable_pat(¶m_place, ¶m.pat);
135 self.consume_expr(&body.value);
138 fn tcx(&self) -> TyCtxt<'tcx> {
142 fn delegate_consume(&mut self, place_with_id: &PlaceWithHirId<'tcx>, diag_expr_id: hir::HirId) {
143 debug!("delegate_consume(place_with_id={:?})", place_with_id);
145 let mode = copy_or_move(&self.mc, place_with_id);
146 self.delegate.consume(place_with_id, diag_expr_id, mode);
149 fn consume_exprs(&mut self, exprs: &[hir::Expr<'_>]) {
151 self.consume_expr(&expr);
155 pub fn consume_expr(&mut self, expr: &hir::Expr<'_>) {
156 debug!("consume_expr(expr={:?})", expr);
158 let place_with_id = return_if_err!(self.mc.cat_expr(expr));
159 self.delegate_consume(&place_with_id, place_with_id.hir_id);
160 self.walk_expr(expr);
163 fn mutate_expr(&mut self, expr: &hir::Expr<'_>) {
164 let place_with_id = return_if_err!(self.mc.cat_expr(expr));
165 self.delegate.mutate(&place_with_id, place_with_id.hir_id);
166 self.walk_expr(expr);
169 fn borrow_expr(&mut self, expr: &hir::Expr<'_>, bk: ty::BorrowKind) {
170 debug!("borrow_expr(expr={:?}, bk={:?})", expr, bk);
172 let place_with_id = return_if_err!(self.mc.cat_expr(expr));
173 self.delegate.borrow(&place_with_id, place_with_id.hir_id, bk);
178 fn select_from_expr(&mut self, expr: &hir::Expr<'_>) {
182 pub fn walk_expr(&mut self, expr: &hir::Expr<'_>) {
183 debug!("walk_expr(expr={:?})", expr);
185 self.walk_adjustment(expr);
188 hir::ExprKind::Path(_) => {}
190 hir::ExprKind::Type(ref subexpr, _) => self.walk_expr(subexpr),
192 hir::ExprKind::Unary(hir::UnOp::Deref, ref base) => {
194 self.select_from_expr(base);
197 hir::ExprKind::Field(ref base, _) => {
199 self.select_from_expr(base);
202 hir::ExprKind::Index(ref lhs, ref rhs) => {
204 self.select_from_expr(lhs);
205 self.consume_expr(rhs);
208 hir::ExprKind::Call(ref callee, ref args) => {
210 self.consume_expr(callee);
211 self.consume_exprs(args);
214 hir::ExprKind::MethodCall(.., ref args, _) => {
216 self.consume_exprs(args);
219 hir::ExprKind::Struct(_, ref fields, ref opt_with) => {
220 self.walk_struct_expr(fields, opt_with);
223 hir::ExprKind::Tup(ref exprs) => {
224 self.consume_exprs(exprs);
227 hir::ExprKind::If(ref cond_expr, ref then_expr, ref opt_else_expr) => {
228 self.consume_expr(&cond_expr);
229 self.consume_expr(&then_expr);
230 if let Some(ref else_expr) = *opt_else_expr {
231 self.consume_expr(&else_expr);
235 hir::ExprKind::Match(ref discr, arms, _) => {
236 let discr_place = return_if_err!(self.mc.cat_expr(&discr));
238 // Matching should not always be considered a use of the place, hence
239 // discr does not necessarily need to be borrowed.
240 // We only want to borrow discr if the pattern contain something other
242 let ExprUseVisitor { ref mc, body_owner: _, delegate: _ } = *self;
243 let mut needs_to_be_read = false;
244 for arm in arms.iter() {
245 return_if_err!(mc.cat_pattern(discr_place.clone(), &arm.pat, |place, pat| {
247 PatKind::Binding(.., opt_sub_pat) => {
248 // If the opt_sub_pat is None, than the binding does not count as
249 // a wildcard for the purpose of borrowing discr.
250 if opt_sub_pat.is_none() {
251 needs_to_be_read = true;
254 PatKind::TupleStruct(..)
256 | PatKind::Struct(..)
257 | PatKind::Tuple(..) => {
258 // If the PatKind is a TupleStruct, Struct or Tuple then we want to check
259 // whether the Variant is a MultiVariant or a SingleVariant. We only want
260 // to borrow discr if it is a MultiVariant.
261 // If it is a SingleVariant and creates a binding we will handle that when
262 // this callback gets called again.
263 if let ty::Adt(def, _) = place.place.base_ty.kind() {
264 if def.variants.len() > 1 {
265 needs_to_be_read = true;
270 // If the PatKind is a Lit then we want
272 needs_to_be_read = true;
279 if needs_to_be_read {
280 self.borrow_expr(&discr, ty::ImmBorrow);
282 self.delegate.fake_read(
283 discr_place.place.clone(),
284 FakeReadCause::ForMatchedPlace,
288 // We always want to walk the discriminant. We want to make sure, for instance,
289 // that the discriminant has been initialized.
290 self.walk_expr(&discr);
293 // treatment of the discriminant is handled while walking the arms.
295 self.walk_arm(&discr_place, arm);
299 hir::ExprKind::Array(ref exprs) => {
300 self.consume_exprs(exprs);
303 hir::ExprKind::AddrOf(_, m, ref base) => {
305 // make sure that the thing we are pointing out stays valid
306 // for the lifetime `scope_r` of the resulting ptr:
307 let bk = ty::BorrowKind::from_mutbl(m);
308 self.borrow_expr(&base, bk);
311 hir::ExprKind::InlineAsm(ref asm) => {
312 for (op, _op_sp) in asm.operands {
314 hir::InlineAsmOperand::In { expr, .. }
315 | hir::InlineAsmOperand::Const { expr, .. }
316 | hir::InlineAsmOperand::Sym { expr, .. } => self.consume_expr(expr),
317 hir::InlineAsmOperand::Out { expr, .. } => {
318 if let Some(expr) = expr {
319 self.mutate_expr(expr);
322 hir::InlineAsmOperand::InOut { expr, .. } => {
323 self.mutate_expr(expr);
325 hir::InlineAsmOperand::SplitInOut { in_expr, out_expr, .. } => {
326 self.consume_expr(in_expr);
327 if let Some(out_expr) = out_expr {
328 self.mutate_expr(out_expr);
335 hir::ExprKind::LlvmInlineAsm(ref ia) => {
336 for (o, output) in ia.inner.outputs.iter().zip(ia.outputs_exprs) {
338 self.consume_expr(output);
340 self.mutate_expr(output);
343 self.consume_exprs(&ia.inputs_exprs);
346 hir::ExprKind::Continue(..)
347 | hir::ExprKind::Lit(..)
348 | hir::ExprKind::ConstBlock(..)
349 | hir::ExprKind::Err => {}
351 hir::ExprKind::Loop(ref blk, ..) => {
352 self.walk_block(blk);
355 hir::ExprKind::Unary(_, ref lhs) => {
356 self.consume_expr(lhs);
359 hir::ExprKind::Binary(_, ref lhs, ref rhs) => {
360 self.consume_expr(lhs);
361 self.consume_expr(rhs);
364 hir::ExprKind::Block(ref blk, _) => {
365 self.walk_block(blk);
368 hir::ExprKind::Break(_, ref opt_expr) | hir::ExprKind::Ret(ref opt_expr) => {
369 if let Some(ref expr) = *opt_expr {
370 self.consume_expr(expr);
374 hir::ExprKind::Assign(ref lhs, ref rhs, _) => {
375 self.mutate_expr(lhs);
376 self.consume_expr(rhs);
379 hir::ExprKind::Cast(ref base, _) => {
380 self.consume_expr(base);
383 hir::ExprKind::DropTemps(ref expr) => {
384 self.consume_expr(expr);
387 hir::ExprKind::AssignOp(_, ref lhs, ref rhs) => {
388 if self.mc.typeck_results.is_method_call(expr) {
389 self.consume_expr(lhs);
391 self.mutate_expr(lhs);
393 self.consume_expr(rhs);
396 hir::ExprKind::Repeat(ref base, _) => {
397 self.consume_expr(base);
400 hir::ExprKind::Closure(..) => {
401 self.walk_captures(expr);
404 hir::ExprKind::Box(ref base) => {
405 self.consume_expr(base);
408 hir::ExprKind::Yield(ref value, _) => {
409 self.consume_expr(value);
414 fn walk_stmt(&mut self, stmt: &hir::Stmt<'_>) {
416 hir::StmtKind::Local(ref local) => {
417 self.walk_local(&local);
420 hir::StmtKind::Item(_) => {
421 // We don't visit nested items in this visitor,
422 // only the fn body we were given.
425 hir::StmtKind::Expr(ref expr) | hir::StmtKind::Semi(ref expr) => {
426 self.consume_expr(&expr);
431 fn walk_local(&mut self, local: &hir::Local<'_>) {
432 if let Some(ref expr) = local.init {
433 // Variable declarations with
434 // initializers are considered
435 // "assigns", which is handled by
437 self.walk_expr(&expr);
438 let init_place = return_if_err!(self.mc.cat_expr(&expr));
439 self.walk_irrefutable_pat(&init_place, &local.pat);
443 /// Indicates that the value of `blk` will be consumed, meaning either copied or moved
444 /// depending on its type.
445 fn walk_block(&mut self, blk: &hir::Block<'_>) {
446 debug!("walk_block(blk.hir_id={})", blk.hir_id);
448 for stmt in blk.stmts {
449 self.walk_stmt(stmt);
452 if let Some(ref tail_expr) = blk.expr {
453 self.consume_expr(&tail_expr);
459 fields: &[hir::ExprField<'_>],
460 opt_with: &Option<&'hir hir::Expr<'_>>,
462 // Consume the expressions supplying values for each field.
463 for field in fields {
464 self.consume_expr(&field.expr);
467 let with_expr = match *opt_with {
474 let with_place = return_if_err!(self.mc.cat_expr(&with_expr));
476 // Select just those fields of the `with`
477 // expression that will actually be used
478 match with_place.place.ty().kind() {
479 ty::Adt(adt, substs) if adt.is_struct() => {
480 // Consume those fields of the with expression that are needed.
481 for (f_index, with_field) in adt.non_enum_variant().fields.iter().enumerate() {
482 let is_mentioned = fields.iter().any(|f| {
483 self.tcx().field_index(f.hir_id, self.mc.typeck_results) == f_index
486 let field_place = self.mc.cat_projection(
489 with_field.ty(self.tcx(), substs),
490 ProjectionKind::Field(f_index as u32, VariantIdx::new(0)),
492 self.delegate_consume(&field_place, field_place.hir_id);
497 // the base expression should always evaluate to a
498 // struct; however, when EUV is run during typeck, it
499 // may not. This will generate an error earlier in typeck,
500 // so we can just ignore it.
501 if !self.tcx().sess.has_errors() {
502 span_bug!(with_expr.span, "with expression doesn't evaluate to a struct");
507 // walk the with expression so that complex expressions
508 // are properly handled.
509 self.walk_expr(with_expr);
512 // Invoke the appropriate delegate calls for anything that gets
513 // consumed or borrowed as part of the automatic adjustment
515 fn walk_adjustment(&mut self, expr: &hir::Expr<'_>) {
516 let adjustments = self.mc.typeck_results.expr_adjustments(expr);
517 let mut place_with_id = return_if_err!(self.mc.cat_expr_unadjusted(expr));
518 for adjustment in adjustments {
519 debug!("walk_adjustment expr={:?} adj={:?}", expr, adjustment);
520 match adjustment.kind {
521 adjustment::Adjust::NeverToAny | adjustment::Adjust::Pointer(_) => {
522 // Creating a closure/fn-pointer or unsizing consumes
523 // the input and stores it into the resulting rvalue.
524 self.delegate_consume(&place_with_id, place_with_id.hir_id);
527 adjustment::Adjust::Deref(None) => {}
529 // Autoderefs for overloaded Deref calls in fact reference
530 // their receiver. That is, if we have `(*x)` where `x`
531 // is of type `Rc<T>`, then this in fact is equivalent to
532 // `x.deref()`. Since `deref()` is declared with `&self`,
533 // this is an autoref of `x`.
534 adjustment::Adjust::Deref(Some(ref deref)) => {
535 let bk = ty::BorrowKind::from_mutbl(deref.mutbl);
536 self.delegate.borrow(&place_with_id, place_with_id.hir_id, bk);
539 adjustment::Adjust::Borrow(ref autoref) => {
540 self.walk_autoref(expr, &place_with_id, autoref);
544 return_if_err!(self.mc.cat_expr_adjusted(expr, place_with_id, &adjustment));
548 /// Walks the autoref `autoref` applied to the autoderef'd
549 /// `expr`. `base_place` is the mem-categorized form of `expr`
550 /// after all relevant autoderefs have occurred.
553 expr: &hir::Expr<'_>,
554 base_place: &PlaceWithHirId<'tcx>,
555 autoref: &adjustment::AutoBorrow<'tcx>,
558 "walk_autoref(expr.hir_id={} base_place={:?} autoref={:?})",
559 expr.hir_id, base_place, autoref
563 adjustment::AutoBorrow::Ref(_, m) => {
564 self.delegate.borrow(
567 ty::BorrowKind::from_mutbl(m.into()),
571 adjustment::AutoBorrow::RawPtr(m) => {
572 debug!("walk_autoref: expr.hir_id={} base_place={:?}", expr.hir_id, base_place);
574 self.delegate.borrow(base_place, base_place.hir_id, ty::BorrowKind::from_mutbl(m));
579 fn walk_arm(&mut self, discr_place: &PlaceWithHirId<'tcx>, arm: &hir::Arm<'_>) {
580 self.delegate.fake_read(
581 discr_place.place.clone(),
582 FakeReadCause::ForMatchedPlace,
585 self.walk_pat(discr_place, &arm.pat);
587 if let Some(hir::Guard::If(ref e)) = arm.guard {
591 self.consume_expr(&arm.body);
594 /// Walks a pat that occurs in isolation (i.e., top-level of fn argument or
595 /// let binding, and *not* a match arm or nested pat.)
596 fn walk_irrefutable_pat(&mut self, discr_place: &PlaceWithHirId<'tcx>, pat: &hir::Pat<'_>) {
597 self.delegate.fake_read(
598 discr_place.place.clone(),
599 FakeReadCause::ForLet,
602 self.walk_pat(discr_place, pat);
605 /// The core driver for walking a pattern
606 fn walk_pat(&mut self, discr_place: &PlaceWithHirId<'tcx>, pat: &hir::Pat<'_>) {
607 debug!("walk_pat(discr_place={:?}, pat={:?})", discr_place, pat);
609 let tcx = self.tcx();
610 let ExprUseVisitor { ref mc, body_owner: _, ref mut delegate } = *self;
611 return_if_err!(mc.cat_pattern(discr_place.clone(), pat, |place, pat| {
612 if let PatKind::Binding(_, canonical_id, ..) = pat.kind {
613 debug!("walk_pat: binding place={:?} pat={:?}", place, pat,);
615 mc.typeck_results.extract_binding_mode(tcx.sess, pat.hir_id, pat.span)
617 debug!("walk_pat: pat.hir_id={:?} bm={:?}", pat.hir_id, bm);
619 // pat_ty: the type of the binding being produced.
620 let pat_ty = return_if_err!(mc.node_ty(pat.hir_id));
621 debug!("walk_pat: pat_ty={:?}", pat_ty);
623 // Each match binding is effectively an assignment to the
624 // binding being produced.
625 let def = Res::Local(canonical_id);
626 if let Ok(ref binding_place) = mc.cat_res(pat.hir_id, pat.span, pat_ty, def) {
627 delegate.mutate(binding_place, binding_place.hir_id);
630 // It is also a borrow or copy/move of the value being matched.
631 // In a cases of pattern like `let pat = upvar`, don't use the span
632 // of the pattern, as this just looks confusing, instead use the span
633 // of the discriminant.
635 ty::BindByReference(m) => {
636 let bk = ty::BorrowKind::from_mutbl(m);
637 delegate.borrow(place, discr_place.hir_id, bk);
639 ty::BindByValue(..) => {
640 let mode = copy_or_move(mc, &place);
641 debug!("walk_pat binding consuming pat");
642 delegate.consume(place, discr_place.hir_id, mode);
650 /// Handle the case where the current body contains a closure.
652 /// When the current body being handled is a closure, then we must make sure that
653 /// - The parent closure only captures Places from the nested closure that are not local to it.
655 /// In the following example the closures `c` only captures `p.x`` even though `incr`
656 /// is a capture of the nested closure
658 /// ```rust,ignore(cannot-test-this-because-pseduo-code)
662 /// let nested = || p.x += incr;
666 /// - When reporting the Place back to the Delegate, ensure that the UpvarId uses the enclosing
667 /// closure as the DefId.
668 fn walk_captures(&mut self, closure_expr: &hir::Expr<'_>) {
669 fn upvar_is_local_variable(
670 upvars: Option<&'tcx FxIndexMap<hir::HirId, hir::Upvar>>,
671 upvar_id: &hir::HirId,
672 body_owner_is_closure: bool,
674 upvars.map(|upvars| !upvars.contains_key(upvar_id)).unwrap_or(body_owner_is_closure)
677 debug!("walk_captures({:?})", closure_expr);
679 let closure_def_id = self.tcx().hir().local_def_id(closure_expr.hir_id).to_def_id();
680 let upvars = self.tcx().upvars_mentioned(self.body_owner);
682 // For purposes of this function, generator and closures are equivalent.
683 let body_owner_is_closure = matches!(
684 self.tcx().type_of(self.body_owner.to_def_id()).kind(),
685 ty::Closure(..) | ty::Generator(..)
688 // If we have a nested closure, we want to include the fake reads present in the nested closure.
689 if let Some(fake_reads) = self.mc.typeck_results.closure_fake_reads.get(&closure_def_id) {
690 for (fake_read, cause, hir_id) in fake_reads.iter() {
691 match fake_read.base {
692 PlaceBase::Upvar(upvar_id) => {
693 if upvar_is_local_variable(
695 &upvar_id.var_path.hir_id,
696 body_owner_is_closure,
698 // The nested closure might be fake reading the current (enclosing) closure's local variables.
699 // The only places we want to fake read before creating the parent closure are the ones that
700 // are not local to it/ defined by it.
702 // ```rust,ignore(cannot-test-this-because-pseduo-code)
704 // let c = || { // fake reads: v1
706 // let e = || { // fake reads: v1, v2
712 // This check is performed when visiting the body of the outermost closure (`c`) and ensures
713 // that we don't add a fake read of v2 in c.
719 "Do not know how to get HirId out of Rvalue and StaticItem {:?}",
724 self.delegate.fake_read(fake_read.clone(), *cause, *hir_id);
728 if let Some(min_captures) = self.mc.typeck_results.closure_min_captures.get(&closure_def_id)
730 for (var_hir_id, min_list) in min_captures.iter() {
731 if upvars.map_or(body_owner_is_closure, |upvars| !upvars.contains_key(var_hir_id)) {
732 // The nested closure might be capturing the current (enclosing) closure's local variables.
733 // We check if the root variable is ever mentioned within the enclosing closure, if not
734 // then for the current body (if it's a closure) these aren't captures, we will ignore them.
737 for captured_place in min_list {
738 let place = &captured_place.place;
739 let capture_info = captured_place.info;
741 let place_base = if body_owner_is_closure {
742 // Mark the place to be captured by the enclosing closure
743 PlaceBase::Upvar(ty::UpvarId::new(*var_hir_id, self.body_owner))
745 // If the body owner isn't a closure then the variable must
746 // be a local variable
747 PlaceBase::Local(*var_hir_id)
749 let place_with_id = PlaceWithHirId::new(
750 capture_info.path_expr_id.unwrap_or(closure_expr.hir_id),
753 place.projections.clone(),
756 match capture_info.capture_kind {
757 ty::UpvarCapture::ByValue(_) => {
758 let mode = copy_or_move(&self.mc, &place_with_id);
759 self.delegate.consume(&place_with_id, place_with_id.hir_id, mode);
761 ty::UpvarCapture::ByRef(upvar_borrow) => {
762 self.delegate.borrow(
764 place_with_id.hir_id,
775 fn copy_or_move<'a, 'tcx>(
776 mc: &mc::MemCategorizationContext<'a, 'tcx>,
777 place_with_id: &PlaceWithHirId<'tcx>,
779 if !mc.type_is_copy_modulo_regions(
780 place_with_id.place.ty(),
781 mc.tcx().hir().span(place_with_id.hir_id),