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use rustc::hir;
use rustc::hir::def::Namespace;
use rustc::hir::def_id::DefId;
use rustc::mir::{
AggregateKind, Constant, Field, Local, LocalKind, Location, Operand,
Place, PlaceBase, PlaceRef, ProjectionElem, Rvalue, Statement, StatementKind,
Static, StaticKind, Terminator, TerminatorKind,
};
use rustc::ty::{self, DefIdTree, Ty, TyCtxt};
use rustc::ty::layout::VariantIdx;
use rustc::ty::print::Print;
use rustc_errors::DiagnosticBuilder;
use syntax_pos::Span;
use syntax::symbol::sym;
use super::borrow_set::BorrowData;
use super::{MirBorrowckCtxt};
use crate::dataflow::move_paths::{InitLocation, LookupResult};
pub(super) struct IncludingDowncast(pub(super) bool);
impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
/// Adds a suggestion when a closure is invoked twice with a moved variable or when a closure
/// is moved after being invoked.
///
/// ```text
/// note: closure cannot be invoked more than once because it moves the variable `dict` out of
/// its environment
/// --> $DIR/issue-42065.rs:16:29
/// |
/// LL | for (key, value) in dict {
/// | ^^^^
/// ```
pub(super) fn add_moved_or_invoked_closure_note(
&self,
location: Location,
place: PlaceRef<'cx, 'tcx>,
diag: &mut DiagnosticBuilder<'_>,
) {
debug!("add_moved_or_invoked_closure_note: location={:?} place={:?}", location, place);
let mut target = place.local_or_deref_local();
for stmt in &self.body[location.block].statements[location.statement_index..] {
debug!("add_moved_or_invoked_closure_note: stmt={:?} target={:?}", stmt, target);
if let StatementKind::Assign(box(into, Rvalue::Use(from))) = &stmt.kind {
debug!("add_fnonce_closure_note: into={:?} from={:?}", into, from);
match from {
Operand::Copy(ref place) |
Operand::Move(ref place) if target == place.local_or_deref_local() =>
target = into.local_or_deref_local(),
_ => {},
}
}
}
// Check if we are attempting to call a closure after it has been invoked.
let terminator = self.body[location.block].terminator();
debug!("add_moved_or_invoked_closure_note: terminator={:?}", terminator);
if let TerminatorKind::Call {
func: Operand::Constant(box Constant {
literal: ty::Const {
ty: &ty::TyS { sty: ty::FnDef(id, _), .. },
..
},
..
}),
args,
..
} = &terminator.kind {
debug!("add_moved_or_invoked_closure_note: id={:?}", id);
if self.infcx.tcx.parent(id) == self.infcx.tcx.lang_items().fn_once_trait() {
let closure = match args.first() {
Some(Operand::Copy(ref place)) |
Some(Operand::Move(ref place)) if target == place.local_or_deref_local() =>
place.local_or_deref_local().unwrap(),
_ => return,
};
debug!("add_moved_or_invoked_closure_note: closure={:?}", closure);
if let ty::Closure(did, _) = self.body.local_decls[closure].ty.sty {
let hir_id = self.infcx.tcx.hir().as_local_hir_id(did).unwrap();
if let Some((span, name)) = self.infcx.tcx.typeck_tables_of(did)
.closure_kind_origins()
.get(hir_id)
{
diag.span_note(
*span,
&format!(
"closure cannot be invoked more than once because it moves the \
variable `{}` out of its environment",
name,
),
);
return;
}
}
}
}
// Check if we are just moving a closure after it has been invoked.
if let Some(target) = target {
if let ty::Closure(did, _) = self.body.local_decls[target].ty.sty {
let hir_id = self.infcx.tcx.hir().as_local_hir_id(did).unwrap();
if let Some((span, name)) = self.infcx.tcx.typeck_tables_of(did)
.closure_kind_origins()
.get(hir_id)
{
diag.span_note(
*span,
&format!(
"closure cannot be moved more than once as it is not `Copy` due to \
moving the variable `{}` out of its environment",
name
),
);
}
}
}
}
/// End-user visible description of `place` if one can be found. If the
/// place is a temporary for instance, None will be returned.
pub(super) fn describe_place(&self, place_ref: PlaceRef<'cx, 'tcx>) -> Option<String> {
self.describe_place_with_options(place_ref, IncludingDowncast(false))
}
/// End-user visible description of `place` if one can be found. If the
/// place is a temporary for instance, None will be returned.
/// `IncludingDowncast` parameter makes the function return `Err` if `ProjectionElem` is
/// `Downcast` and `IncludingDowncast` is true
pub(super) fn describe_place_with_options(
&self,
place: PlaceRef<'cx, 'tcx>,
including_downcast: IncludingDowncast,
) -> Option<String> {
let mut buf = String::new();
match self.append_place_to_string(place, &mut buf, false, &including_downcast) {
Ok(()) => Some(buf),
Err(()) => None,
}
}
/// Appends end-user visible description of `place` to `buf`.
fn append_place_to_string(
&self,
place: PlaceRef<'cx, 'tcx>,
buf: &mut String,
mut autoderef: bool,
including_downcast: &IncludingDowncast,
) -> Result<(), ()> {
match place {
PlaceRef {
base: PlaceBase::Local(local),
projection: [],
} => {
self.append_local_to_string(*local, buf)?;
}
PlaceRef {
base:
PlaceBase::Static(box Static {
kind: StaticKind::Promoted(..),
..
}),
projection: [],
} => {
buf.push_str("promoted");
}
PlaceRef {
base:
PlaceBase::Static(box Static {
kind: StaticKind::Static,
def_id,
..
}),
projection: [],
} => {
buf.push_str(&self.infcx.tcx.item_name(*def_id).to_string());
}
PlaceRef {
base,
projection: [proj_base @ .., elem],
} => {
match elem {
ProjectionElem::Deref => {
let upvar_field_projection =
self.is_upvar_field_projection(place);
if let Some(field) = upvar_field_projection {
let var_index = field.index();
let name = self.upvars[var_index].name.to_string();
if self.upvars[var_index].by_ref {
buf.push_str(&name);
} else {
buf.push_str(&format!("*{}", &name));
}
} else {
if autoderef {
// FIXME turn this recursion into iteration
self.append_place_to_string(
PlaceRef {
base,
projection: proj_base,
},
buf,
autoderef,
&including_downcast,
)?;
} else {
match (proj_base, base) {
([], PlaceBase::Local(local)) => {
if self.body.local_decls[*local].is_ref_for_guard() {
self.append_place_to_string(
PlaceRef {
base,
projection: proj_base,
},
buf,
autoderef,
&including_downcast,
)?;
} else {
// FIXME deduplicate this and the _ => body below
buf.push_str(&"*");
self.append_place_to_string(
PlaceRef {
base,
projection: proj_base,
},
buf,
autoderef,
&including_downcast,
)?;
}
}
_ => {
buf.push_str(&"*");
self.append_place_to_string(
PlaceRef {
base,
projection: proj_base,
},
buf,
autoderef,
&including_downcast,
)?;
}
}
}
}
}
ProjectionElem::Downcast(..) => {
self.append_place_to_string(
PlaceRef {
base,
projection: proj_base,
},
buf,
autoderef,
&including_downcast,
)?;
if including_downcast.0 {
return Err(());
}
}
ProjectionElem::Field(field, _ty) => {
autoderef = true;
let upvar_field_projection =
self.is_upvar_field_projection(place);
if let Some(field) = upvar_field_projection {
let var_index = field.index();
let name = self.upvars[var_index].name.to_string();
buf.push_str(&name);
} else {
let field_name = self.describe_field(PlaceRef {
base,
projection: proj_base,
}, *field);
self.append_place_to_string(
PlaceRef {
base,
projection: proj_base,
},
buf,
autoderef,
&including_downcast,
)?;
buf.push_str(&format!(".{}", field_name));
}
}
ProjectionElem::Index(index) => {
autoderef = true;
self.append_place_to_string(
PlaceRef {
base,
projection: proj_base,
},
buf,
autoderef,
&including_downcast,
)?;
buf.push_str("[");
if self.append_local_to_string(*index, buf).is_err() {
buf.push_str("_");
}
buf.push_str("]");
}
ProjectionElem::ConstantIndex { .. } | ProjectionElem::Subslice { .. } => {
autoderef = true;
// Since it isn't possible to borrow an element on a particular index and
// then use another while the borrow is held, don't output indices details
// to avoid confusing the end-user
self.append_place_to_string(
PlaceRef {
base,
projection: proj_base,
},
buf,
autoderef,
&including_downcast,
)?;
buf.push_str(&"[..]");
}
};
}
}
Ok(())
}
/// Appends end-user visible description of the `local` place to `buf`. If `local` doesn't have
/// a name, or its name was generated by the compiler, then `Err` is returned
fn append_local_to_string(&self, local_index: Local, buf: &mut String) -> Result<(), ()> {
let local = &self.body.local_decls[local_index];
match local.name {
Some(name) if !local.from_compiler_desugaring() => {
buf.push_str(&name.as_str());
Ok(())
}
_ => Err(()),
}
}
/// End-user visible description of the `field`nth field of `base`
fn describe_field(&self, place: PlaceRef<'cx, 'tcx>, field: Field) -> String {
// FIXME Place2 Make this work iteratively
match place {
PlaceRef {
base: PlaceBase::Local(local),
projection: [],
} => {
let local = &self.body.local_decls[*local];
self.describe_field_from_ty(&local.ty, field, None)
}
PlaceRef {
base: PlaceBase::Static(static_),
projection: [],
} =>
self.describe_field_from_ty(&static_.ty, field, None),
PlaceRef {
base,
projection: [proj_base @ .., elem],
} => match elem {
ProjectionElem::Deref => {
self.describe_field(PlaceRef {
base,
projection: proj_base,
}, field)
}
ProjectionElem::Downcast(_, variant_index) => {
let base_ty =
Place::ty_from(place.base, place.projection, self.body, self.infcx.tcx).ty;
self.describe_field_from_ty(&base_ty, field, Some(*variant_index))
}
ProjectionElem::Field(_, field_type) => {
self.describe_field_from_ty(&field_type, field, None)
}
ProjectionElem::Index(..)
| ProjectionElem::ConstantIndex { .. }
| ProjectionElem::Subslice { .. } => {
self.describe_field(PlaceRef {
base,
projection: proj_base,
}, field)
}
},
}
}
/// End-user visible description of the `field_index`nth field of `ty`
fn describe_field_from_ty(
&self,
ty: Ty<'_>,
field: Field,
variant_index: Option<VariantIdx>
) -> String {
if ty.is_box() {
// If the type is a box, the field is described from the boxed type
self.describe_field_from_ty(&ty.boxed_ty(), field, variant_index)
} else {
match ty.sty {
ty::Adt(def, _) => {
let variant = if let Some(idx) = variant_index {
assert!(def.is_enum());
&def.variants[idx]
} else {
def.non_enum_variant()
};
variant.fields[field.index()]
.ident
.to_string()
},
ty::Tuple(_) => field.index().to_string(),
ty::Ref(_, ty, _) | ty::RawPtr(ty::TypeAndMut { ty, .. }) => {
self.describe_field_from_ty(&ty, field, variant_index)
}
ty::Array(ty, _) | ty::Slice(ty) =>
self.describe_field_from_ty(&ty, field, variant_index),
ty::Closure(def_id, _) | ty::Generator(def_id, _, _) => {
// `tcx.upvars(def_id)` returns an `Option`, which is `None` in case
// the closure comes from another crate. But in that case we wouldn't
// be borrowck'ing it, so we can just unwrap:
let (&var_id, _) = self.infcx.tcx.upvars(def_id).unwrap()
.get_index(field.index()).unwrap();
self.infcx.tcx.hir().name(var_id).to_string()
}
_ => {
// Might need a revision when the fields in trait RFC is implemented
// (https://github.com/rust-lang/rfcs/pull/1546)
bug!(
"End-user description not implemented for field access on `{:?}`",
ty
);
}
}
}
}
/// Checks if a place is a thread-local static.
pub fn is_place_thread_local(&self, place_ref: PlaceRef<'cx, 'tcx>) -> bool {
if let PlaceRef {
base: PlaceBase::Static(box Static {
kind: StaticKind::Static,
def_id,
..
}),
projection: [],
} = place_ref {
let attrs = self.infcx.tcx.get_attrs(*def_id);
let is_thread_local = attrs.iter().any(|attr| attr.check_name(sym::thread_local));
debug!(
"is_place_thread_local: attrs={:?} is_thread_local={:?}",
attrs, is_thread_local
);
is_thread_local
} else {
debug!("is_place_thread_local: no");
false
}
}
/// Add a note that a type does not implement `Copy`
pub(super) fn note_type_does_not_implement_copy(
&self,
err: &mut DiagnosticBuilder<'a>,
place_desc: &str,
ty: Ty<'tcx>,
span: Option<Span>,
) {
let message = format!(
"move occurs because {} has type `{}`, which does not implement the `Copy` trait",
place_desc,
ty,
);
if let Some(span) = span {
err.span_label(span, message);
} else {
err.note(&message);
}
}
pub(super) fn borrowed_content_source(
&self,
deref_base: PlaceRef<'cx, 'tcx>,
) -> BorrowedContentSource<'tcx> {
let tcx = self.infcx.tcx;
// Look up the provided place and work out the move path index for it,
// we'll use this to check whether it was originally from an overloaded
// operator.
match self.move_data.rev_lookup.find(deref_base) {
LookupResult::Exact(mpi) | LookupResult::Parent(Some(mpi)) => {
debug!("borrowed_content_source: mpi={:?}", mpi);
for i in &self.move_data.init_path_map[mpi] {
let init = &self.move_data.inits[*i];
debug!("borrowed_content_source: init={:?}", init);
// We're only interested in statements that initialized a value, not the
// initializations from arguments.
let loc = match init.location {
InitLocation::Statement(stmt) => stmt,
_ => continue,
};
let bbd = &self.body[loc.block];
let is_terminator = bbd.statements.len() == loc.statement_index;
debug!(
"borrowed_content_source: loc={:?} is_terminator={:?}",
loc,
is_terminator,
);
if !is_terminator {
continue;
} else if let Some(Terminator {
kind: TerminatorKind::Call {
ref func,
from_hir_call: false,
..
},
..
}) = bbd.terminator {
if let Some(source)
= BorrowedContentSource::from_call(func.ty(self.body, tcx), tcx)
{
return source;
}
}
}
}
// Base is a `static` so won't be from an overloaded operator
_ => (),
};
// If we didn't find an overloaded deref or index, then assume it's a
// built in deref and check the type of the base.
let base_ty = Place::ty_from(deref_base.base, deref_base.projection, self.body, tcx).ty;
if base_ty.is_unsafe_ptr() {
BorrowedContentSource::DerefRawPointer
} else if base_ty.is_mutable_ptr() {
BorrowedContentSource::DerefMutableRef
} else {
BorrowedContentSource::DerefSharedRef
}
}
}
impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
/// Return the name of the provided `Ty` (that must be a reference) with a synthesized lifetime
/// name where required.
pub(super) fn get_name_for_ty(&self, ty: Ty<'tcx>, counter: usize) -> String {
let mut s = String::new();
let mut printer = ty::print::FmtPrinter::new(self.infcx.tcx, &mut s, Namespace::TypeNS);
// We need to add synthesized lifetimes where appropriate. We do
// this by hooking into the pretty printer and telling it to label the
// lifetimes without names with the value `'0`.
match ty.sty {
ty::Ref(ty::RegionKind::ReLateBound(_, br), _, _)
| ty::Ref(
ty::RegionKind::RePlaceholder(ty::PlaceholderRegion { name: br, .. }),
_,
_,
) => printer.region_highlight_mode.highlighting_bound_region(*br, counter),
_ => {}
}
let _ = ty.print(printer);
s
}
/// Returns the name of the provided `Ty` (that must be a reference)'s region with a
/// synthesized lifetime name where required.
pub(super) fn get_region_name_for_ty(&self, ty: Ty<'tcx>, counter: usize) -> String {
let mut s = String::new();
let mut printer = ty::print::FmtPrinter::new(self.infcx.tcx, &mut s, Namespace::TypeNS);
let region = match ty.sty {
ty::Ref(region, _, _) => {
match region {
ty::RegionKind::ReLateBound(_, br)
| ty::RegionKind::RePlaceholder(ty::PlaceholderRegion { name: br, .. }) => {
printer.region_highlight_mode.highlighting_bound_region(*br, counter)
}
_ => {}
}
region
}
_ => bug!("ty for annotation of borrow region is not a reference"),
};
let _ = region.print(printer);
s
}
}
// The span(s) associated to a use of a place.
#[derive(Copy, Clone, PartialEq, Eq, Debug)]
pub(super) enum UseSpans {
// The access is caused by capturing a variable for a closure.
ClosureUse {
// This is true if the captured variable was from a generator.
is_generator: bool,
// The span of the args of the closure, including the `move` keyword if
// it's present.
args_span: Span,
// The span of the first use of the captured variable inside the closure.
var_span: Span,
},
// This access has a single span associated to it: common case.
OtherUse(Span),
}
impl UseSpans {
pub(super) fn args_or_use(self) -> Span {
match self {
UseSpans::ClosureUse {
args_span: span, ..
}
| UseSpans::OtherUse(span) => span,
}
}
pub(super) fn var_or_use(self) -> Span {
match self {
UseSpans::ClosureUse { var_span: span, .. } | UseSpans::OtherUse(span) => span,
}
}
// Add a span label to the arguments of the closure, if it exists.
pub(super) fn args_span_label(
self,
err: &mut DiagnosticBuilder<'_>,
message: impl Into<String>,
) {
if let UseSpans::ClosureUse { args_span, .. } = self {
err.span_label(args_span, message);
}
}
// Add a span label to the use of the captured variable, if it exists.
pub(super) fn var_span_label(
self,
err: &mut DiagnosticBuilder<'_>,
message: impl Into<String>,
) {
if let UseSpans::ClosureUse { var_span, .. } = self {
err.span_label(var_span, message);
}
}
/// Returns `false` if this place is not used in a closure.
pub(super) fn for_closure(&self) -> bool {
match *self {
UseSpans::ClosureUse { is_generator, .. } => !is_generator,
_ => false,
}
}
/// Returns `false` if this place is not used in a generator.
pub(super) fn for_generator(&self) -> bool {
match *self {
UseSpans::ClosureUse { is_generator, .. } => is_generator,
_ => false,
}
}
/// Describe the span associated with a use of a place.
pub(super) fn describe(&self) -> String {
match *self {
UseSpans::ClosureUse { is_generator, .. } => if is_generator {
" in generator".to_string()
} else {
" in closure".to_string()
},
_ => "".to_string(),
}
}
pub(super) fn or_else<F>(self, if_other: F) -> Self
where
F: FnOnce() -> Self,
{
match self {
closure @ UseSpans::ClosureUse { .. } => closure,
UseSpans::OtherUse(_) => if_other(),
}
}
}
pub(super) enum BorrowedContentSource<'tcx> {
DerefRawPointer,
DerefMutableRef,
DerefSharedRef,
OverloadedDeref(Ty<'tcx>),
OverloadedIndex(Ty<'tcx>),
}
impl BorrowedContentSource<'tcx> {
pub(super) fn describe_for_unnamed_place(&self) -> String {
match *self {
BorrowedContentSource::DerefRawPointer => format!("a raw pointer"),
BorrowedContentSource::DerefSharedRef => format!("a shared reference"),
BorrowedContentSource::DerefMutableRef => {
format!("a mutable reference")
}
BorrowedContentSource::OverloadedDeref(ty) => {
if ty.is_rc() {
format!("an `Rc`")
} else if ty.is_arc() {
format!("an `Arc`")
} else {
format!("dereference of `{}`", ty)
}
}
BorrowedContentSource::OverloadedIndex(ty) => format!("index of `{}`", ty),
}
}
pub(super) fn describe_for_named_place(&self) -> Option<&'static str> {
match *self {
BorrowedContentSource::DerefRawPointer => Some("raw pointer"),
BorrowedContentSource::DerefSharedRef => Some("shared reference"),
BorrowedContentSource::DerefMutableRef => Some("mutable reference"),
// Overloaded deref and index operators should be evaluated into a
// temporary. So we don't need a description here.
BorrowedContentSource::OverloadedDeref(_)
| BorrowedContentSource::OverloadedIndex(_) => None
}
}
pub(super) fn describe_for_immutable_place(&self) -> String {
match *self {
BorrowedContentSource::DerefRawPointer => format!("a `*const` pointer"),
BorrowedContentSource::DerefSharedRef => format!("a `&` reference"),
BorrowedContentSource::DerefMutableRef => {
bug!("describe_for_immutable_place: DerefMutableRef isn't immutable")
},
BorrowedContentSource::OverloadedDeref(ty) => {
if ty.is_rc() {
format!("an `Rc`")
} else if ty.is_arc() {
format!("an `Arc`")
} else {
format!("a dereference of `{}`", ty)
}
}
BorrowedContentSource::OverloadedIndex(ty) => format!("an index of `{}`", ty),
}
}
fn from_call(func: Ty<'tcx>, tcx: TyCtxt<'tcx>) -> Option<Self> {
match func.sty {
ty::FnDef(def_id, substs) => {
let trait_id = tcx.trait_of_item(def_id)?;
let lang_items = tcx.lang_items();
if Some(trait_id) == lang_items.deref_trait()
|| Some(trait_id) == lang_items.deref_mut_trait()
{
Some(BorrowedContentSource::OverloadedDeref(substs.type_at(0)))
} else if Some(trait_id) == lang_items.index_trait()
|| Some(trait_id) == lang_items.index_mut_trait()
{
Some(BorrowedContentSource::OverloadedIndex(substs.type_at(0)))
} else {
None
}
}
_ => None,
}
}
}
impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
/// Finds the spans associated to a move or copy of move_place at location.
pub(super) fn move_spans(
&self,
moved_place: PlaceRef<'cx, 'tcx>, // Could also be an upvar.
location: Location,
) -> UseSpans {
use self::UseSpans::*;
let stmt = match self.body[location.block].statements.get(location.statement_index) {
Some(stmt) => stmt,
None => return OtherUse(self.body.source_info(location).span),
};
debug!("move_spans: moved_place={:?} location={:?} stmt={:?}", moved_place, location, stmt);
if let StatementKind::Assign(
box(_, Rvalue::Aggregate(ref kind, ref places))
) = stmt.kind {
let (def_id, is_generator) = match kind {
box AggregateKind::Closure(def_id, _) => (def_id, false),
box AggregateKind::Generator(def_id, _, _) => (def_id, true),
_ => return OtherUse(stmt.source_info.span),
};
debug!(
"move_spans: def_id={:?} is_generator={:?} places={:?}",
def_id, is_generator, places
);
if let Some((args_span, var_span)) = self.closure_span(*def_id, moved_place, places) {
return ClosureUse {
is_generator,
args_span,
var_span,
};
}
}
OtherUse(stmt.source_info.span)
}
/// Finds the span of arguments of a closure (within `maybe_closure_span`)
/// and its usage of the local assigned at `location`.
/// This is done by searching in statements succeeding `location`
/// and originating from `maybe_closure_span`.
pub(super) fn borrow_spans(&self, use_span: Span, location: Location) -> UseSpans {
use self::UseSpans::*;
debug!("borrow_spans: use_span={:?} location={:?}", use_span, location);
let target = match self.body[location.block]
.statements
.get(location.statement_index)
{
Some(&Statement {
kind: StatementKind::Assign(box(Place {
base: PlaceBase::Local(local),
projection: box [],
}, _)),
..
}) => local,
_ => return OtherUse(use_span),
};
if self.body.local_kind(target) != LocalKind::Temp {
// operands are always temporaries.
return OtherUse(use_span);
}
for stmt in &self.body[location.block].statements[location.statement_index + 1..] {
if let StatementKind::Assign(
box(_, Rvalue::Aggregate(ref kind, ref places))
) = stmt.kind {
let (def_id, is_generator) = match kind {
box AggregateKind::Closure(def_id, _) => (def_id, false),
box AggregateKind::Generator(def_id, _, _) => (def_id, true),
_ => continue,
};
debug!(
"borrow_spans: def_id={:?} is_generator={:?} places={:?}",
def_id, is_generator, places
);
if let Some((args_span, var_span)) = self.closure_span(
*def_id, Place::from(target).as_ref(), places
) {
return ClosureUse {
is_generator,
args_span,
var_span,
};
} else {
return OtherUse(use_span);
}
}
if use_span != stmt.source_info.span {
break;
}
}
OtherUse(use_span)
}
/// Finds the span of a captured variable within a closure or generator.
fn closure_span(
&self,
def_id: DefId,
target_place: PlaceRef<'cx, 'tcx>,
places: &Vec<Operand<'tcx>>,
) -> Option<(Span, Span)> {
debug!(
"closure_span: def_id={:?} target_place={:?} places={:?}",
def_id, target_place, places
);
let hir_id = self.infcx.tcx.hir().as_local_hir_id(def_id)?;
let expr = &self.infcx.tcx.hir().expect_expr(hir_id).node;
debug!("closure_span: hir_id={:?} expr={:?}", hir_id, expr);
if let hir::ExprKind::Closure(
.., args_span, _
) = expr {
for (upvar, place) in self.infcx.tcx.upvars(def_id)?.values().zip(places) {
match place {
Operand::Copy(place) |
Operand::Move(place) if target_place == place.as_ref() => {
debug!("closure_span: found captured local {:?}", place);
return Some((*args_span, upvar.span));
},
_ => {}
}
}
}
None
}
/// Helper to retrieve span(s) of given borrow from the current MIR
/// representation
pub(super) fn retrieve_borrow_spans(&self, borrow: &BorrowData<'_>) -> UseSpans {
let span = self.body.source_info(borrow.reserve_location).span;
self.borrow_spans(span, borrow.reserve_location)
}
}
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