Remove unused parts of ExprUseVisitor
This commit is contained in:
parent
455945f24b
commit
b4ad612697
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@ -2,20 +2,16 @@
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//! normal visitor, which just walks the entire body in one shot, the
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//! `ExprUseVisitor` determines how expressions are being used.
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pub use self::LoanCause::*;
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pub use self::ConsumeMode::*;
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pub use self::MoveReason::*;
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pub use self::MatchMode::*;
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use self::TrackMatchMode::*;
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use self::OverloadedCallType::*;
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use crate::hir::def::{CtorOf, Res, DefKind};
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use crate::hir::def::Res;
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use crate::hir::def_id::DefId;
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use crate::hir::ptr::P;
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use crate::infer::InferCtxt;
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use crate::middle::mem_categorization as mc;
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use crate::middle::region;
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use crate::ty::{self, DefIdTree, TyCtxt, adjustment};
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use crate::ty::{self, TyCtxt, adjustment};
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use crate::hir::{self, PatKind};
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use std::rc::Rc;
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@ -29,161 +25,19 @@ use syntax_pos::Span;
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pub trait Delegate<'tcx> {
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// The value found at `cmt` is either copied or moved, depending
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// on mode.
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fn consume(&mut self,
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consume_id: hir::HirId,
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consume_span: Span,
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cmt: &mc::cmt_<'tcx>,
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mode: ConsumeMode);
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fn consume(&mut self, cmt: &mc::cmt_<'tcx>, mode: ConsumeMode);
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// The value found at `cmt` has been determined to match the
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// pattern binding `matched_pat`, and its subparts are being
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// copied or moved depending on `mode`. Note that `matched_pat`
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// is called on all variant/structs in the pattern (i.e., the
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// interior nodes of the pattern's tree structure) while
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// consume_pat is called on the binding identifiers in the pattern
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// (which are leaves of the pattern's tree structure).
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//
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// Note that variants/structs and identifiers are disjoint; thus
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// `matched_pat` and `consume_pat` are never both called on the
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// same input pattern structure (though of `consume_pat` can be
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// called on a subpart of an input passed to `matched_pat).
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fn matched_pat(&mut self,
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matched_pat: &hir::Pat,
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cmt: &mc::cmt_<'tcx>,
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mode: MatchMode);
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// The value found at `cmt` is either copied or moved via the
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// pattern binding `consume_pat`, depending on mode.
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fn consume_pat(&mut self,
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consume_pat: &hir::Pat,
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cmt: &mc::cmt_<'tcx>,
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mode: ConsumeMode);
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// The value found at `borrow` is being borrowed at the point
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// `borrow_id` for the region `loan_region` with kind `bk`.
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fn borrow(&mut self,
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borrow_id: hir::HirId,
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borrow_span: Span,
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cmt: &mc::cmt_<'tcx>,
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loan_region: ty::Region<'tcx>,
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bk: ty::BorrowKind,
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loan_cause: LoanCause);
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// The local variable `id` is declared but not initialized.
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fn decl_without_init(&mut self,
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id: hir::HirId,
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span: Span);
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// The value found at `cmt` is being borrowed with kind `bk`.
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fn borrow(&mut self, cmt: &mc::cmt_<'tcx>, bk: ty::BorrowKind);
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// The path at `cmt` is being assigned to.
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fn mutate(&mut self,
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assignment_id: hir::HirId,
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assignment_span: Span,
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assignee_cmt: &mc::cmt_<'tcx>,
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mode: MutateMode);
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// A nested closure or generator - only one layer deep.
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fn nested_body(&mut self, _body_id: hir::BodyId) {}
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}
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#[derive(Copy, Clone, PartialEq, Debug)]
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pub enum LoanCause {
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ClosureCapture(Span),
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AddrOf,
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AutoRef,
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AutoUnsafe,
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RefBinding,
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OverloadedOperator,
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ClosureInvocation,
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ForLoop,
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MatchDiscriminant
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fn mutate(&mut self, assignee_cmt: &mc::cmt_<'tcx>);
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}
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#[derive(Copy, Clone, PartialEq, Debug)]
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pub enum ConsumeMode {
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Copy, // reference to x where x has a type that copies
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Move(MoveReason), // reference to x where x has a type that moves
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}
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#[derive(Copy, Clone, PartialEq, Debug)]
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pub enum MoveReason {
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DirectRefMove,
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PatBindingMove,
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CaptureMove,
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}
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#[derive(Copy, Clone, PartialEq, Debug)]
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pub enum MatchMode {
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NonBindingMatch,
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BorrowingMatch,
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CopyingMatch,
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MovingMatch,
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}
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#[derive(Copy, Clone, PartialEq, Debug)]
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enum TrackMatchMode {
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Unknown,
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Definite(MatchMode),
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Conflicting,
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}
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impl TrackMatchMode {
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// Builds up the whole match mode for a pattern from its constituent
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// parts. The lattice looks like this:
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//
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// Conflicting
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// / \
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// / \
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// Borrowing Moving
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// \ /
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// \ /
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// Copying
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// |
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// NonBinding
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// |
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// Unknown
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//
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// examples:
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//
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// * `(_, some_int)` pattern is Copying, since
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// NonBinding + Copying => Copying
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//
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// * `(some_int, some_box)` pattern is Moving, since
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// Copying + Moving => Moving
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//
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// * `(ref x, some_box)` pattern is Conflicting, since
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// Borrowing + Moving => Conflicting
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//
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// Note that the `Unknown` and `Conflicting` states are
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// represented separately from the other more interesting
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// `Definite` states, which simplifies logic here somewhat.
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fn lub(&mut self, mode: MatchMode) {
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*self = match (*self, mode) {
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// Note that clause order below is very significant.
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(Unknown, new) => Definite(new),
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(Definite(old), new) if old == new => Definite(old),
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(Definite(old), NonBindingMatch) => Definite(old),
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(Definite(NonBindingMatch), new) => Definite(new),
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(Definite(old), CopyingMatch) => Definite(old),
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(Definite(CopyingMatch), new) => Definite(new),
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(Definite(_), _) => Conflicting,
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(Conflicting, _) => *self,
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};
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}
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fn match_mode(&self) -> MatchMode {
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match *self {
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Unknown => NonBindingMatch,
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Definite(mode) => mode,
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Conflicting => {
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// Conservatively return MovingMatch to let the
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// compiler continue to make progress.
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MovingMatch
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}
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}
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}
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Move, // reference to x where x has a type that moves
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}
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#[derive(Copy, Clone, PartialEq, Debug)]
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@ -326,15 +180,11 @@ impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
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self.mc.tcx
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}
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fn delegate_consume(&mut self,
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consume_id: hir::HirId,
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consume_span: Span,
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cmt: &mc::cmt_<'tcx>) {
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debug!("delegate_consume(consume_id={}, cmt={:?})",
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consume_id, cmt);
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fn delegate_consume(&mut self, cmt: &mc::cmt_<'tcx>) {
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debug!("delegate_consume(cmt={:?})", cmt);
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let mode = copy_or_move(&self.mc, self.param_env, cmt, DirectRefMove);
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self.delegate.consume(consume_id, consume_span, cmt, mode);
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let mode = copy_or_move(&self.mc, self.param_env, cmt);
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self.delegate.consume(cmt, mode);
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}
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fn consume_exprs(&mut self, exprs: &[hir::Expr]) {
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@ -347,30 +197,21 @@ impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
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debug!("consume_expr(expr={:?})", expr);
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let cmt = return_if_err!(self.mc.cat_expr(expr));
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self.delegate_consume(expr.hir_id, expr.span, &cmt);
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self.delegate_consume(&cmt);
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self.walk_expr(expr);
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}
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fn mutate_expr(&mut self,
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span: Span,
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assignment_expr: &hir::Expr,
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expr: &hir::Expr,
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mode: MutateMode) {
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fn mutate_expr(&mut self, expr: &hir::Expr) {
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let cmt = return_if_err!(self.mc.cat_expr(expr));
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self.delegate.mutate(assignment_expr.hir_id, span, &cmt, mode);
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self.delegate.mutate(&cmt);
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self.walk_expr(expr);
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}
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fn borrow_expr(&mut self,
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expr: &hir::Expr,
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r: ty::Region<'tcx>,
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bk: ty::BorrowKind,
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cause: LoanCause) {
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debug!("borrow_expr(expr={:?}, r={:?}, bk={:?})",
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expr, r, bk);
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fn borrow_expr(&mut self, expr: &hir::Expr, bk: ty::BorrowKind) {
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debug!("borrow_expr(expr={:?}, bk={:?})", expr, bk);
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let cmt = return_if_err!(self.mc.cat_expr(expr));
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self.delegate.borrow(expr.hir_id, expr.span, &cmt, r, bk, cause);
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self.delegate.borrow(&cmt, bk);
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self.walk_expr(expr)
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}
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@ -388,24 +229,24 @@ impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
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hir::ExprKind::Path(_) => { }
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hir::ExprKind::Type(ref subexpr, _) => {
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self.walk_expr(&subexpr)
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self.walk_expr(subexpr)
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}
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hir::ExprKind::Unary(hir::UnDeref, ref base) => { // *base
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self.select_from_expr(&base);
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self.select_from_expr(base);
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}
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hir::ExprKind::Field(ref base, _) => { // base.f
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self.select_from_expr(&base);
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self.select_from_expr(base);
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}
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hir::ExprKind::Index(ref lhs, ref rhs) => { // lhs[rhs]
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self.select_from_expr(&lhs);
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self.consume_expr(&rhs);
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self.select_from_expr(lhs);
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self.consume_expr(rhs);
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}
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hir::ExprKind::Call(ref callee, ref args) => { // callee(args)
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self.walk_callee(expr, &callee);
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self.walk_callee(expr, callee);
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self.consume_exprs(args);
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}
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@ -423,14 +264,11 @@ impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
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hir::ExprKind::Match(ref discr, ref arms, _) => {
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let discr_cmt = Rc::new(return_if_err!(self.mc.cat_expr(&discr)));
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let r = self.tcx().lifetimes.re_empty;
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self.borrow_expr(&discr, r, ty::ImmBorrow, MatchDiscriminant);
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self.borrow_expr(&discr, ty::ImmBorrow);
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// treatment of the discriminant is handled while walking the arms.
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for arm in arms {
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let mode = self.arm_move_mode(discr_cmt.clone(), arm);
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let mode = mode.match_mode();
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self.walk_arm(discr_cmt.clone(), arm, mode);
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self.walk_arm(discr_cmt.clone(), arm);
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}
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}
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@ -441,11 +279,8 @@ impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
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hir::ExprKind::AddrOf(m, ref base) => { // &base
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// make sure that the thing we are pointing out stays valid
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// for the lifetime `scope_r` of the resulting ptr:
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let expr_ty = return_if_err!(self.mc.expr_ty(expr));
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if let ty::Ref(r, _, _) = expr_ty.kind {
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let bk = ty::BorrowKind::from_mutbl(m);
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self.borrow_expr(&base, r, bk, AddrOf);
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}
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let bk = ty::BorrowKind::from_mutbl(m);
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self.borrow_expr(&base, bk);
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}
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hir::ExprKind::InlineAsm(ref ia, ref outputs, ref inputs) => {
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@ -453,16 +288,7 @@ impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
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if o.is_indirect {
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self.consume_expr(output);
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} else {
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self.mutate_expr(
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output.span,
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expr,
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output,
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if o.is_rw {
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MutateMode::WriteAndRead
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} else {
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MutateMode::JustWrite
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},
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);
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self.mutate_expr(output);
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}
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}
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self.consume_exprs(inputs);
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@ -473,65 +299,64 @@ impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
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hir::ExprKind::Err => {}
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hir::ExprKind::Loop(ref blk, _, _) => {
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self.walk_block(&blk);
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self.walk_block(blk);
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}
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hir::ExprKind::Unary(_, ref lhs) => {
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self.consume_expr(&lhs);
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self.consume_expr(lhs);
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}
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hir::ExprKind::Binary(_, ref lhs, ref rhs) => {
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self.consume_expr(&lhs);
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self.consume_expr(&rhs);
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self.consume_expr(lhs);
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self.consume_expr(rhs);
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}
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hir::ExprKind::Block(ref blk, _) => {
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self.walk_block(&blk);
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self.walk_block(blk);
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}
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hir::ExprKind::Break(_, ref opt_expr) | hir::ExprKind::Ret(ref opt_expr) => {
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if let Some(ref expr) = *opt_expr {
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self.consume_expr(&expr);
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self.consume_expr(expr);
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}
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}
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hir::ExprKind::Assign(ref lhs, ref rhs) => {
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self.mutate_expr(expr.span, expr, &lhs, MutateMode::JustWrite);
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self.consume_expr(&rhs);
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self.mutate_expr(lhs);
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self.consume_expr(rhs);
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}
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hir::ExprKind::Cast(ref base, _) => {
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self.consume_expr(&base);
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self.consume_expr(base);
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}
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hir::ExprKind::DropTemps(ref expr) => {
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self.consume_expr(&expr);
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self.consume_expr(expr);
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}
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hir::ExprKind::AssignOp(_, ref lhs, ref rhs) => {
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if self.mc.tables.is_method_call(expr) {
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self.consume_expr(lhs);
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} else {
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self.mutate_expr(expr.span, expr, &lhs, MutateMode::WriteAndRead);
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self.mutate_expr(lhs);
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}
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self.consume_expr(&rhs);
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self.consume_expr(rhs);
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}
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hir::ExprKind::Repeat(ref base, _) => {
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self.consume_expr(&base);
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self.consume_expr(base);
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}
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hir::ExprKind::Closure(_, _, body_id, fn_decl_span, _) => {
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self.delegate.nested_body(body_id);
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hir::ExprKind::Closure(_, _, _, fn_decl_span, _) => {
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self.walk_captures(expr, fn_decl_span);
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}
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hir::ExprKind::Box(ref base) => {
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self.consume_expr(&base);
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self.consume_expr(base);
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}
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hir::ExprKind::Yield(ref value, _) => {
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self.consume_expr(&value);
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self.consume_expr(value);
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}
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}
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}
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@ -547,24 +372,12 @@ impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
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ty::Error => { }
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_ => {
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if let Some(def_id) = self.mc.tables.type_dependent_def_id(call.hir_id) {
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let call_scope = region::Scope {
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id: call.hir_id.local_id,
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data: region::ScopeData::Node
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};
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match OverloadedCallType::from_method_id(self.tcx(), def_id) {
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FnMutOverloadedCall => {
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let call_scope_r = self.tcx().mk_region(ty::ReScope(call_scope));
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self.borrow_expr(callee,
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call_scope_r,
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ty::MutBorrow,
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ClosureInvocation);
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self.borrow_expr(callee, ty::MutBorrow);
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}
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FnOverloadedCall => {
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let call_scope_r = self.tcx().mk_region(ty::ReScope(call_scope));
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self.borrow_expr(callee,
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call_scope_r,
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ty::ImmBorrow,
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ClosureInvocation);
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self.borrow_expr(callee, ty::ImmBorrow);
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}
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FnOnceOverloadedCall => self.consume_expr(callee),
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}
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@ -595,22 +408,14 @@ impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
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}
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fn walk_local(&mut self, local: &hir::Local) {
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match local.init {
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None => {
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local.pat.each_binding(|_, hir_id, span, _| {
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self.delegate.decl_without_init(hir_id, span);
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})
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}
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Some(ref expr) => {
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// Variable declarations with
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// initializers are considered
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// "assigns", which is handled by
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// `walk_pat`:
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self.walk_expr(&expr);
|
||||
let init_cmt = Rc::new(return_if_err!(self.mc.cat_expr(&expr)));
|
||||
self.walk_irrefutable_pat(init_cmt, &local.pat);
|
||||
}
|
||||
if let Some(ref expr) = local.init {
|
||||
// Variable declarations with
|
||||
// initializers are considered
|
||||
// "assigns", which is handled by
|
||||
// `walk_pat`:
|
||||
self.walk_expr(&expr);
|
||||
let init_cmt = Rc::new(return_if_err!(self.mc.cat_expr(&expr)));
|
||||
self.walk_irrefutable_pat(init_cmt, &local.pat);
|
||||
}
|
||||
}
|
||||
|
||||
|
@ -660,7 +465,7 @@ impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
|
|||
with_field.ident,
|
||||
with_field.ty(self.tcx(), substs)
|
||||
);
|
||||
self.delegate_consume(with_expr.hir_id, with_expr.span, &cmt_field);
|
||||
self.delegate_consume(&cmt_field);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
@ -695,7 +500,7 @@ impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
|
|||
adjustment::Adjust::Pointer(_) => {
|
||||
// Creating a closure/fn-pointer or unsizing consumes
|
||||
// the input and stores it into the resulting rvalue.
|
||||
self.delegate_consume(expr.hir_id, expr.span, &cmt);
|
||||
self.delegate_consume(&cmt);
|
||||
}
|
||||
|
||||
adjustment::Adjust::Deref(None) => {}
|
||||
|
@ -707,7 +512,7 @@ impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
|
|||
// this is an autoref of `x`.
|
||||
adjustment::Adjust::Deref(Some(ref deref)) => {
|
||||
let bk = ty::BorrowKind::from_mutbl(deref.mutbl);
|
||||
self.delegate.borrow(expr.hir_id, expr.span, &cmt, deref.region, bk, AutoRef);
|
||||
self.delegate.borrow(&cmt, bk);
|
||||
}
|
||||
|
||||
adjustment::Adjust::Borrow(ref autoref) => {
|
||||
|
@ -731,13 +536,8 @@ impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
|
|||
autoref);
|
||||
|
||||
match *autoref {
|
||||
adjustment::AutoBorrow::Ref(r, m) => {
|
||||
self.delegate.borrow(expr.hir_id,
|
||||
expr.span,
|
||||
cmt_base,
|
||||
r,
|
||||
ty::BorrowKind::from_mutbl(m.into()),
|
||||
AutoRef);
|
||||
adjustment::AutoBorrow::Ref(_, m) => {
|
||||
self.delegate.borrow(cmt_base, ty::BorrowKind::from_mutbl(m.into()));
|
||||
}
|
||||
|
||||
adjustment::AutoBorrow::RawPtr(m) => {
|
||||
|
@ -745,33 +545,14 @@ impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
|
|||
expr.hir_id,
|
||||
cmt_base);
|
||||
|
||||
// Converting from a &T to *T (or &mut T to *mut T) is
|
||||
// treated as borrowing it for the enclosing temporary
|
||||
// scope.
|
||||
let r = self.tcx().mk_region(ty::ReScope(
|
||||
region::Scope {
|
||||
id: expr.hir_id.local_id,
|
||||
data: region::ScopeData::Node
|
||||
}));
|
||||
|
||||
self.delegate.borrow(expr.hir_id,
|
||||
expr.span,
|
||||
cmt_base,
|
||||
r,
|
||||
ty::BorrowKind::from_mutbl(m),
|
||||
AutoUnsafe);
|
||||
self.delegate.borrow(cmt_base, ty::BorrowKind::from_mutbl(m));
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
fn arm_move_mode(&mut self, discr_cmt: mc::cmt<'tcx>, arm: &hir::Arm) -> TrackMatchMode {
|
||||
let mut mode = Unknown;
|
||||
self.determine_pat_move_mode(discr_cmt.clone(), &arm.pat, &mut mode);
|
||||
mode
|
||||
}
|
||||
|
||||
fn walk_arm(&mut self, discr_cmt: mc::cmt<'tcx>, arm: &hir::Arm, mode: MatchMode) {
|
||||
self.walk_pat(discr_cmt.clone(), &arm.pat, mode);
|
||||
fn walk_arm(&mut self, discr_cmt: mc::cmt<'tcx>, arm: &hir::Arm) {
|
||||
self.walk_pat(discr_cmt.clone(), &arm.pat);
|
||||
|
||||
if let Some(hir::Guard::If(ref e)) = arm.guard {
|
||||
self.consume_expr(e)
|
||||
|
@ -783,44 +564,12 @@ impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
|
|||
/// Walks a pat that occurs in isolation (i.e., top-level of fn argument or
|
||||
/// let binding, and *not* a match arm or nested pat.)
|
||||
fn walk_irrefutable_pat(&mut self, cmt_discr: mc::cmt<'tcx>, pat: &hir::Pat) {
|
||||
let mut mode = Unknown;
|
||||
self.determine_pat_move_mode(cmt_discr.clone(), pat, &mut mode);
|
||||
let mode = mode.match_mode();
|
||||
self.walk_pat(cmt_discr, pat, mode);
|
||||
self.walk_pat(cmt_discr, pat);
|
||||
}
|
||||
|
||||
/// Identifies any bindings within `pat` and accumulates within
|
||||
/// `mode` whether the overall pattern/match structure is a move,
|
||||
/// copy, or borrow.
|
||||
fn determine_pat_move_mode(&mut self,
|
||||
cmt_discr: mc::cmt<'tcx>,
|
||||
pat: &hir::Pat,
|
||||
mode: &mut TrackMatchMode) {
|
||||
debug!("determine_pat_move_mode cmt_discr={:?} pat={:?}", cmt_discr, pat);
|
||||
|
||||
return_if_err!(self.mc.cat_pattern(cmt_discr, pat, |cmt_pat, pat| {
|
||||
if let PatKind::Binding(..) = pat.kind {
|
||||
let bm = *self.mc.tables.pat_binding_modes()
|
||||
.get(pat.hir_id)
|
||||
.expect("missing binding mode");
|
||||
match bm {
|
||||
ty::BindByReference(..) =>
|
||||
mode.lub(BorrowingMatch),
|
||||
ty::BindByValue(..) => {
|
||||
match copy_or_move(&self.mc, self.param_env, &cmt_pat, PatBindingMove) {
|
||||
Copy => mode.lub(CopyingMatch),
|
||||
Move(..) => mode.lub(MovingMatch),
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
}));
|
||||
}
|
||||
|
||||
/// The core driver for walking a pattern; `match_mode` must be
|
||||
/// established up front, e.g., via `determine_pat_move_mode` (see
|
||||
/// also `walk_irrefutable_pat` for patterns that stand alone).
|
||||
fn walk_pat(&mut self, cmt_discr: mc::cmt<'tcx>, pat: &hir::Pat, match_mode: MatchMode) {
|
||||
/// The core driver for walking a pattern
|
||||
fn walk_pat(&mut self, cmt_discr: mc::cmt<'tcx>, pat: &hir::Pat) {
|
||||
debug!("walk_pat(cmt_discr={:?}, pat={:?})", cmt_discr, pat);
|
||||
|
||||
let tcx = self.tcx();
|
||||
|
@ -828,10 +577,9 @@ impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
|
|||
return_if_err!(mc.cat_pattern(cmt_discr.clone(), pat, |cmt_pat, pat| {
|
||||
if let PatKind::Binding(_, canonical_id, ..) = pat.kind {
|
||||
debug!(
|
||||
"walk_pat: binding cmt_pat={:?} pat={:?} match_mode={:?}",
|
||||
"walk_pat: binding cmt_pat={:?} pat={:?}",
|
||||
cmt_pat,
|
||||
pat,
|
||||
match_mode,
|
||||
);
|
||||
if let Some(&bm) = mc.tables.pat_binding_modes().get(pat.hir_id) {
|
||||
debug!("walk_pat: pat.hir_id={:?} bm={:?}", pat.hir_id, bm);
|
||||
|
@ -844,21 +592,19 @@ impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
|
|||
// binding being produced.
|
||||
let def = Res::Local(canonical_id);
|
||||
if let Ok(ref binding_cmt) = mc.cat_res(pat.hir_id, pat.span, pat_ty, def) {
|
||||
delegate.mutate(pat.hir_id, pat.span, binding_cmt, MutateMode::Init);
|
||||
delegate.mutate(binding_cmt);
|
||||
}
|
||||
|
||||
// It is also a borrow or copy/move of the value being matched.
|
||||
match bm {
|
||||
ty::BindByReference(m) => {
|
||||
if let ty::Ref(r, _, _) = pat_ty.kind {
|
||||
let bk = ty::BorrowKind::from_mutbl(m);
|
||||
delegate.borrow(pat.hir_id, pat.span, &cmt_pat, r, bk, RefBinding);
|
||||
}
|
||||
let bk = ty::BorrowKind::from_mutbl(m);
|
||||
delegate.borrow(&cmt_pat, bk);
|
||||
}
|
||||
ty::BindByValue(..) => {
|
||||
let mode = copy_or_move(mc, param_env, &cmt_pat, PatBindingMove);
|
||||
let mode = copy_or_move(mc, param_env, &cmt_pat);
|
||||
debug!("walk_pat binding consuming pat");
|
||||
delegate.consume_pat(pat, &cmt_pat, mode);
|
||||
delegate.consume(&cmt_pat, mode);
|
||||
}
|
||||
}
|
||||
} else {
|
||||
|
@ -866,45 +612,6 @@ impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
|
|||
}
|
||||
}
|
||||
}));
|
||||
|
||||
// Do a second pass over the pattern, calling `matched_pat` on
|
||||
// the interior nodes (enum variants and structs), as opposed
|
||||
// to the above loop's visit of than the bindings that form
|
||||
// the leaves of the pattern tree structure.
|
||||
return_if_err!(mc.cat_pattern(cmt_discr, pat, |cmt_pat, pat| {
|
||||
let qpath = match pat.kind {
|
||||
PatKind::Path(ref qpath) |
|
||||
PatKind::TupleStruct(ref qpath, ..) |
|
||||
PatKind::Struct(ref qpath, ..) => qpath,
|
||||
_ => return
|
||||
};
|
||||
let res = mc.tables.qpath_res(qpath, pat.hir_id);
|
||||
match res {
|
||||
Res::Def(DefKind::Ctor(CtorOf::Variant, ..), variant_ctor_did) => {
|
||||
let variant_did = mc.tcx.parent(variant_ctor_did).unwrap();
|
||||
let downcast_cmt = mc.cat_downcast_if_needed(pat, cmt_pat, variant_did);
|
||||
|
||||
debug!("variantctor downcast_cmt={:?} pat={:?}", downcast_cmt, pat);
|
||||
delegate.matched_pat(pat, &downcast_cmt, match_mode);
|
||||
}
|
||||
Res::Def(DefKind::Variant, variant_did) => {
|
||||
let downcast_cmt = mc.cat_downcast_if_needed(pat, cmt_pat, variant_did);
|
||||
|
||||
debug!("variant downcast_cmt={:?} pat={:?}", downcast_cmt, pat);
|
||||
delegate.matched_pat(pat, &downcast_cmt, match_mode);
|
||||
}
|
||||
Res::Def(DefKind::Struct, _)
|
||||
| Res::Def(DefKind::Ctor(..), _)
|
||||
| Res::Def(DefKind::Union, _)
|
||||
| Res::Def(DefKind::TyAlias, _)
|
||||
| Res::Def(DefKind::AssocTy, _)
|
||||
| Res::SelfTy(..) => {
|
||||
debug!("struct cmt_pat={:?} pat={:?}", cmt_pat, pat);
|
||||
delegate.matched_pat(pat, &cmt_pat, match_mode);
|
||||
}
|
||||
_ => {}
|
||||
}
|
||||
}));
|
||||
}
|
||||
|
||||
fn walk_captures(&mut self, closure_expr: &hir::Expr, fn_decl_span: Span) {
|
||||
|
@ -912,7 +619,7 @@ impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
|
|||
|
||||
let closure_def_id = self.tcx().hir().local_def_id(closure_expr.hir_id);
|
||||
if let Some(upvars) = self.tcx().upvars(closure_def_id) {
|
||||
for (&var_id, upvar) in upvars.iter() {
|
||||
for &var_id in upvars.keys() {
|
||||
let upvar_id = ty::UpvarId {
|
||||
var_path: ty::UpvarPath { hir_id: var_id },
|
||||
closure_expr_id: closure_def_id.to_local(),
|
||||
|
@ -923,19 +630,11 @@ impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
|
|||
var_id));
|
||||
match upvar_capture {
|
||||
ty::UpvarCapture::ByValue => {
|
||||
let mode = copy_or_move(&self.mc,
|
||||
self.param_env,
|
||||
&cmt_var,
|
||||
CaptureMove);
|
||||
self.delegate.consume(closure_expr.hir_id, upvar.span, &cmt_var, mode);
|
||||
let mode = copy_or_move(&self.mc, self.param_env, &cmt_var);
|
||||
self.delegate.consume(&cmt_var, mode);
|
||||
}
|
||||
ty::UpvarCapture::ByRef(upvar_borrow) => {
|
||||
self.delegate.borrow(closure_expr.hir_id,
|
||||
fn_decl_span,
|
||||
&cmt_var,
|
||||
upvar_borrow.region,
|
||||
upvar_borrow.kind,
|
||||
ClosureCapture(upvar.span));
|
||||
self.delegate.borrow(&cmt_var, upvar_borrow.kind);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
@ -958,10 +657,9 @@ fn copy_or_move<'a, 'tcx>(
|
|||
mc: &mc::MemCategorizationContext<'a, 'tcx>,
|
||||
param_env: ty::ParamEnv<'tcx>,
|
||||
cmt: &mc::cmt_<'tcx>,
|
||||
move_reason: MoveReason,
|
||||
) -> ConsumeMode {
|
||||
if !mc.type_is_copy_modulo_regions(param_env, cmt.ty, cmt.span) {
|
||||
Move(move_reason)
|
||||
Move
|
||||
} else {
|
||||
Copy
|
||||
}
|
||||
|
|
|
@ -321,7 +321,7 @@ impl<'a, 'tcx> InferBorrowKind<'a, 'tcx> {
|
|||
euv::Copy => {
|
||||
return;
|
||||
}
|
||||
euv::Move(_) => {}
|
||||
euv::Move => {}
|
||||
}
|
||||
|
||||
let tcx = self.fcx.tcx;
|
||||
|
@ -582,48 +582,13 @@ impl<'a, 'tcx> InferBorrowKind<'a, 'tcx> {
|
|||
}
|
||||
|
||||
impl<'a, 'tcx> euv::Delegate<'tcx> for InferBorrowKind<'a, 'tcx> {
|
||||
fn consume(
|
||||
&mut self,
|
||||
_consume_id: hir::HirId,
|
||||
_consume_span: Span,
|
||||
cmt: &mc::cmt_<'tcx>,
|
||||
mode: euv::ConsumeMode,
|
||||
) {
|
||||
fn consume(&mut self, cmt: &mc::cmt_<'tcx>,mode: euv::ConsumeMode) {
|
||||
debug!("consume(cmt={:?},mode={:?})", cmt, mode);
|
||||
self.adjust_upvar_borrow_kind_for_consume(cmt, mode);
|
||||
}
|
||||
|
||||
fn matched_pat(
|
||||
&mut self,
|
||||
_matched_pat: &hir::Pat,
|
||||
_cmt: &mc::cmt_<'tcx>,
|
||||
_mode: euv::MatchMode,
|
||||
) {
|
||||
}
|
||||
|
||||
fn consume_pat(
|
||||
&mut self,
|
||||
_consume_pat: &hir::Pat,
|
||||
cmt: &mc::cmt_<'tcx>,
|
||||
mode: euv::ConsumeMode,
|
||||
) {
|
||||
debug!("consume_pat(cmt={:?},mode={:?})", cmt, mode);
|
||||
self.adjust_upvar_borrow_kind_for_consume(cmt, mode);
|
||||
}
|
||||
|
||||
fn borrow(
|
||||
&mut self,
|
||||
borrow_id: hir::HirId,
|
||||
_borrow_span: Span,
|
||||
cmt: &mc::cmt_<'tcx>,
|
||||
_loan_region: ty::Region<'tcx>,
|
||||
bk: ty::BorrowKind,
|
||||
_loan_cause: euv::LoanCause,
|
||||
) {
|
||||
debug!(
|
||||
"borrow(borrow_id={}, cmt={:?}, bk={:?})",
|
||||
borrow_id, cmt, bk
|
||||
);
|
||||
fn borrow(&mut self, cmt: &mc::cmt_<'tcx>, bk: ty::BorrowKind) {
|
||||
debug!("borrow(cmt={:?}, bk={:?})", cmt, bk);
|
||||
|
||||
match bk {
|
||||
ty::ImmBorrow => {}
|
||||
|
@ -636,15 +601,7 @@ impl<'a, 'tcx> euv::Delegate<'tcx> for InferBorrowKind<'a, 'tcx> {
|
|||
}
|
||||
}
|
||||
|
||||
fn decl_without_init(&mut self, _id: hir::HirId, _span: Span) {}
|
||||
|
||||
fn mutate(
|
||||
&mut self,
|
||||
_assignment_id: hir::HirId,
|
||||
_assignment_span: Span,
|
||||
assignee_cmt: &mc::cmt_<'tcx>,
|
||||
_mode: euv::MutateMode,
|
||||
) {
|
||||
fn mutate(&mut self, assignee_cmt: &mc::cmt_<'tcx>) {
|
||||
debug!("mutate(assignee_cmt={:?})", assignee_cmt);
|
||||
|
||||
self.adjust_upvar_borrow_kind_for_mut(assignee_cmt);
|
||||
|
|
Loading…
Reference in New Issue