1244 lines
49 KiB
Rust
1244 lines
49 KiB
Rust
use crate::hair::*;
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use crate::hair::cx::Cx;
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use crate::hair::cx::block;
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use crate::hair::cx::to_ref::ToRef;
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use crate::hair::util::UserAnnotatedTyHelpers;
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use rustc_data_structures::indexed_vec::Idx;
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use rustc::hir::def::{CtorOf, Res, DefKind, CtorKind};
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use rustc::mir::interpret::{GlobalId, ErrorHandled, ConstValue};
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use rustc::ty::{self, AdtKind, DefIdTree, Ty};
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use rustc::ty::adjustment::{Adjustment, Adjust, AutoBorrow, AutoBorrowMutability, PointerCast};
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use rustc::ty::subst::{InternalSubsts, SubstsRef};
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use rustc::hir;
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use rustc::hir::def_id::LocalDefId;
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use rustc::mir::BorrowKind;
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use syntax_pos::Span;
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impl<'tcx> Mirror<'tcx> for &'tcx hir::Expr {
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type Output = Expr<'tcx>;
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fn make_mirror<'a, 'gcx>(self, cx: &mut Cx<'a, 'gcx, 'tcx>) -> Expr<'tcx> {
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let temp_lifetime = cx.region_scope_tree.temporary_scope(self.hir_id.local_id);
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let expr_scope = region::Scope {
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id: self.hir_id.local_id,
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data: region::ScopeData::Node
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};
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debug!("Expr::make_mirror(): id={}, span={:?}", self.hir_id, self.span);
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let mut expr = make_mirror_unadjusted(cx, self);
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// Now apply adjustments, if any.
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for adjustment in cx.tables().expr_adjustments(self) {
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debug!("make_mirror: expr={:?} applying adjustment={:?}",
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expr,
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adjustment);
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expr = apply_adjustment(cx, self, expr, adjustment);
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}
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// Next, wrap this up in the expr's scope.
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expr = Expr {
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temp_lifetime,
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ty: expr.ty,
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span: self.span,
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kind: ExprKind::Scope {
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region_scope: expr_scope,
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value: expr.to_ref(),
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lint_level: LintLevel::Explicit(self.hir_id),
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},
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};
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// Finally, create a destruction scope, if any.
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if let Some(region_scope) =
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cx.region_scope_tree.opt_destruction_scope(self.hir_id.local_id) {
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expr = Expr {
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temp_lifetime,
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ty: expr.ty,
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span: self.span,
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kind: ExprKind::Scope {
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region_scope,
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value: expr.to_ref(),
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lint_level: LintLevel::Inherited,
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},
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};
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}
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// OK, all done!
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expr
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}
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}
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fn apply_adjustment<'a, 'gcx, 'tcx>(cx: &mut Cx<'a, 'gcx, 'tcx>,
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hir_expr: &'tcx hir::Expr,
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mut expr: Expr<'tcx>,
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adjustment: &Adjustment<'tcx>)
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-> Expr<'tcx> {
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let Expr { temp_lifetime, mut span, .. } = expr;
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// Adjust the span from the block, to the last expression of the
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// block. This is a better span when returning a mutable reference
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// with too short a lifetime. The error message will use the span
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// from the assignment to the return place, which should only point
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// at the returned value, not the entire function body.
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//
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// fn return_short_lived<'a>(x: &'a mut i32) -> &'static mut i32 {
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// x
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// // ^ error message points at this expression.
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// }
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let mut adjust_span = |expr: &mut Expr<'tcx>| {
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if let ExprKind::Block { body } = expr.kind {
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if let Some(ref last_expr) = body.expr {
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span = last_expr.span;
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expr.span = span;
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}
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}
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};
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let kind = match adjustment.kind {
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Adjust::Pointer(PointerCast::Unsize) => {
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adjust_span(&mut expr);
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ExprKind::Pointer { cast: PointerCast::Unsize, source: expr.to_ref() }
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}
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Adjust::Pointer(cast) => {
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ExprKind::Pointer { cast, source: expr.to_ref() }
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}
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Adjust::NeverToAny => {
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ExprKind::NeverToAny { source: expr.to_ref() }
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}
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Adjust::Deref(None) => {
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adjust_span(&mut expr);
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ExprKind::Deref { arg: expr.to_ref() }
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}
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Adjust::Deref(Some(deref)) => {
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// We don't need to do call adjust_span here since
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// deref coercions always start with a built-in deref.
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let call = deref.method_call(cx.tcx(), expr.ty);
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expr = Expr {
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temp_lifetime,
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ty: cx.tcx.mk_ref(deref.region,
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ty::TypeAndMut {
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ty: expr.ty,
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mutbl: deref.mutbl,
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}),
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span,
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kind: ExprKind::Borrow {
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borrow_kind: deref.mutbl.to_borrow_kind(),
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arg: expr.to_ref(),
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},
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};
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overloaded_place(cx, hir_expr, adjustment.target, Some(call), vec![expr.to_ref()])
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}
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Adjust::Borrow(AutoBorrow::Ref(_, m)) => {
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ExprKind::Borrow {
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borrow_kind: m.to_borrow_kind(),
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arg: expr.to_ref(),
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}
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}
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Adjust::Borrow(AutoBorrow::RawPtr(m)) => {
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// Convert this to a suitable `&foo` and
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// then an unsafe coercion.
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expr = Expr {
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temp_lifetime,
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ty: cx.tcx.mk_ref(cx.tcx.lifetimes.re_erased,
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ty::TypeAndMut {
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ty: expr.ty,
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mutbl: m,
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}),
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span,
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kind: ExprKind::Borrow {
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borrow_kind: m.to_borrow_kind(),
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arg: expr.to_ref(),
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},
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};
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let cast_expr = Expr {
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temp_lifetime,
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ty: adjustment.target,
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span,
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kind: ExprKind::Cast { source: expr.to_ref() }
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};
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// To ensure that both implicit and explicit coercions are
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// handled the same way, we insert an extra layer of indirection here.
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// For explicit casts (e.g., 'foo as *const T'), the source of the 'Use'
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// will be an ExprKind::Hair with the appropriate cast expression. Here,
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// we make our Use source the generated Cast from the original coercion.
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//
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// In both cases, this outer 'Use' ensures that the inner 'Cast' is handled by
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// as_operand, not by as_rvalue - causing the cast result to be stored in a temporary.
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// Ordinary, this is identical to using the cast directly as an rvalue. However, if the
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// source of the cast was previously borrowed as mutable, storing the cast in a
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// temporary gives the source a chance to expire before the cast is used. For
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// structs with a self-referential *mut ptr, this allows assignment to work as
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// expected.
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//
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// For example, consider the type 'struct Foo { field: *mut Foo }',
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// The method 'fn bar(&mut self) { self.field = self }'
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// triggers a coercion from '&mut self' to '*mut self'. In order
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// for the assignment to be valid, the implicit borrow
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// of 'self' involved in the coercion needs to end before the local
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// containing the '*mut T' is assigned to 'self.field' - otherwise,
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// we end up trying to assign to 'self.field' while we have another mutable borrow
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// active.
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//
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// We only need to worry about this kind of thing for coercions from refs to ptrs,
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// since they get rid of a borrow implicitly.
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ExprKind::Use { source: cast_expr.to_ref() }
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}
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};
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Expr {
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temp_lifetime,
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ty: adjustment.target,
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span,
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kind,
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}
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}
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fn make_mirror_unadjusted<'a, 'gcx, 'tcx>(cx: &mut Cx<'a, 'gcx, 'tcx>,
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expr: &'tcx hir::Expr)
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-> Expr<'tcx> {
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let expr_ty = cx.tables().expr_ty(expr);
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let temp_lifetime = cx.region_scope_tree.temporary_scope(expr.hir_id.local_id);
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let kind = match expr.node {
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// Here comes the interesting stuff:
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hir::ExprKind::MethodCall(_, method_span, ref args) => {
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// Rewrite a.b(c) into UFCS form like Trait::b(a, c)
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let expr = method_callee(cx, expr, method_span,None);
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let args = args.iter()
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.map(|e| e.to_ref())
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.collect();
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ExprKind::Call {
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ty: expr.ty,
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fun: expr.to_ref(),
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args,
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from_hir_call: true,
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}
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}
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hir::ExprKind::Call(ref fun, ref args) => {
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if cx.tables().is_method_call(expr) {
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// The callee is something implementing Fn, FnMut, or FnOnce.
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// Find the actual method implementation being called and
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// build the appropriate UFCS call expression with the
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// callee-object as expr parameter.
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// rewrite f(u, v) into FnOnce::call_once(f, (u, v))
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let method = method_callee(cx, expr, fun.span,None);
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let arg_tys = args.iter().map(|e| cx.tables().expr_ty_adjusted(e));
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let tupled_args = Expr {
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ty: cx.tcx.mk_tup(arg_tys),
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temp_lifetime,
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span: expr.span,
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kind: ExprKind::Tuple { fields: args.iter().map(ToRef::to_ref).collect() },
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};
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ExprKind::Call {
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ty: method.ty,
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fun: method.to_ref(),
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args: vec![fun.to_ref(), tupled_args.to_ref()],
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from_hir_call: true,
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}
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} else {
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let adt_data = if let hir::ExprKind::Path(hir::QPath::Resolved(_, ref path)) =
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fun.node
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{
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// Tuple-like ADTs are represented as ExprKind::Call. We convert them here.
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expr_ty.ty_adt_def().and_then(|adt_def| {
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match path.res {
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Res::Def(DefKind::Ctor(_, CtorKind::Fn), ctor_id) =>
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Some((adt_def, adt_def.variant_index_with_ctor_id(ctor_id))),
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Res::SelfCtor(..) => Some((adt_def, VariantIdx::new(0))),
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_ => None,
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}
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})
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} else {
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None
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};
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if let Some((adt_def, index)) = adt_data {
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let substs = cx.tables().node_substs(fun.hir_id);
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let user_provided_types = cx.tables().user_provided_types();
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let user_ty = user_provided_types.get(fun.hir_id)
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.map(|u_ty| *u_ty)
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.map(|mut u_ty| {
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if let UserType::TypeOf(ref mut did, _) = &mut u_ty.value {
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*did = adt_def.did;
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}
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u_ty
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});
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debug!("make_mirror_unadjusted: (call) user_ty={:?}", user_ty);
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let field_refs = args.iter()
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.enumerate()
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.map(|(idx, e)| {
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FieldExprRef {
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name: Field::new(idx),
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expr: e.to_ref(),
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}
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})
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.collect();
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ExprKind::Adt {
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adt_def,
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substs,
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variant_index: index,
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fields: field_refs,
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user_ty,
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base: None,
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}
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} else {
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ExprKind::Call {
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ty: cx.tables().node_type(fun.hir_id),
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fun: fun.to_ref(),
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args: args.to_ref(),
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from_hir_call: true,
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}
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}
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}
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}
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hir::ExprKind::AddrOf(mutbl, ref expr) => {
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ExprKind::Borrow {
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borrow_kind: mutbl.to_borrow_kind(),
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arg: expr.to_ref(),
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}
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}
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hir::ExprKind::Block(ref blk, _) => ExprKind::Block { body: &blk },
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hir::ExprKind::Assign(ref lhs, ref rhs) => {
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ExprKind::Assign {
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lhs: lhs.to_ref(),
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rhs: rhs.to_ref(),
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}
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}
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hir::ExprKind::AssignOp(op, ref lhs, ref rhs) => {
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if cx.tables().is_method_call(expr) {
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overloaded_operator(cx, expr, vec![lhs.to_ref(), rhs.to_ref()])
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} else {
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ExprKind::AssignOp {
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op: bin_op(op.node),
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lhs: lhs.to_ref(),
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rhs: rhs.to_ref(),
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}
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}
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}
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hir::ExprKind::Lit(ref lit) => ExprKind::Literal {
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literal: cx.const_eval_literal(&lit.node, expr_ty, lit.span, false),
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user_ty: None,
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},
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hir::ExprKind::Binary(op, ref lhs, ref rhs) => {
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if cx.tables().is_method_call(expr) {
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overloaded_operator(cx, expr, vec![lhs.to_ref(), rhs.to_ref()])
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} else {
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// FIXME overflow
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match (op.node, cx.constness) {
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// FIXME(eddyb) use logical ops in constants when
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// they can handle that kind of control-flow.
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(hir::BinOpKind::And, hir::Constness::Const) => {
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cx.control_flow_destroyed.push((
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op.span,
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"`&&` operator".into(),
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));
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ExprKind::Binary {
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op: BinOp::BitAnd,
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lhs: lhs.to_ref(),
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rhs: rhs.to_ref(),
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}
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}
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(hir::BinOpKind::Or, hir::Constness::Const) => {
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cx.control_flow_destroyed.push((
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op.span,
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"`||` operator".into(),
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));
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ExprKind::Binary {
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op: BinOp::BitOr,
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lhs: lhs.to_ref(),
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rhs: rhs.to_ref(),
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}
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}
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(hir::BinOpKind::And, hir::Constness::NotConst) => {
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ExprKind::LogicalOp {
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op: LogicalOp::And,
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lhs: lhs.to_ref(),
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rhs: rhs.to_ref(),
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}
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}
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(hir::BinOpKind::Or, hir::Constness::NotConst) => {
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ExprKind::LogicalOp {
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op: LogicalOp::Or,
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lhs: lhs.to_ref(),
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rhs: rhs.to_ref(),
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}
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}
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_ => {
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let op = bin_op(op.node);
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ExprKind::Binary {
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op,
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lhs: lhs.to_ref(),
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rhs: rhs.to_ref(),
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}
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}
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}
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}
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}
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hir::ExprKind::Index(ref lhs, ref index) => {
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if cx.tables().is_method_call(expr) {
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overloaded_place(cx, expr, expr_ty, None, vec![lhs.to_ref(), index.to_ref()])
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} else {
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ExprKind::Index {
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lhs: lhs.to_ref(),
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index: index.to_ref(),
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}
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}
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}
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hir::ExprKind::Unary(hir::UnOp::UnDeref, ref arg) => {
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if cx.tables().is_method_call(expr) {
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overloaded_place(cx, expr, expr_ty, None, vec![arg.to_ref()])
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} else {
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ExprKind::Deref { arg: arg.to_ref() }
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}
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}
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hir::ExprKind::Unary(hir::UnOp::UnNot, ref arg) => {
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if cx.tables().is_method_call(expr) {
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overloaded_operator(cx, expr, vec![arg.to_ref()])
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} else {
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ExprKind::Unary {
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op: UnOp::Not,
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arg: arg.to_ref(),
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}
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}
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}
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hir::ExprKind::Unary(hir::UnOp::UnNeg, ref arg) => {
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if cx.tables().is_method_call(expr) {
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overloaded_operator(cx, expr, vec![arg.to_ref()])
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} else {
|
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if let hir::ExprKind::Lit(ref lit) = arg.node {
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ExprKind::Literal {
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literal: cx.const_eval_literal(&lit.node, expr_ty, lit.span, true),
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user_ty: None,
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}
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} else {
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ExprKind::Unary {
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op: UnOp::Neg,
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arg: arg.to_ref(),
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}
|
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}
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}
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}
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|
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hir::ExprKind::Struct(ref qpath, ref fields, ref base) => {
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match expr_ty.sty {
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ty::Adt(adt, substs) => {
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match adt.adt_kind() {
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AdtKind::Struct | AdtKind::Union => {
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let user_provided_types = cx.tables().user_provided_types();
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let user_ty = user_provided_types.get(expr.hir_id).map(|u_ty| *u_ty);
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debug!("make_mirror_unadjusted: (struct/union) user_ty={:?}", user_ty);
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ExprKind::Adt {
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adt_def: adt,
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variant_index: VariantIdx::new(0),
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substs,
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user_ty,
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fields: field_refs(cx, fields),
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base: base.as_ref().map(|base| {
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FruInfo {
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base: base.to_ref(),
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field_types: cx.tables()
|
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.fru_field_types()[expr.hir_id]
|
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.clone(),
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}
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}),
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}
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}
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AdtKind::Enum => {
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let res = cx.tables().qpath_res(qpath, expr.hir_id);
|
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match res {
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Res::Def(DefKind::Variant, variant_id) => {
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assert!(base.is_none());
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|
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let index = adt.variant_index_with_id(variant_id);
|
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let user_provided_types = cx.tables().user_provided_types();
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let user_ty = user_provided_types.get(expr.hir_id)
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.map(|u_ty| *u_ty);
|
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debug!(
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"make_mirror_unadjusted: (variant) user_ty={:?}",
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user_ty
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);
|
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ExprKind::Adt {
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|
adt_def: adt,
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variant_index: index,
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substs,
|
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user_ty,
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fields: field_refs(cx, fields),
|
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base: None,
|
|
}
|
|
}
|
|
_ => {
|
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span_bug!(expr.span, "unexpected res: {:?}", res);
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}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
_ => {
|
|
span_bug!(expr.span,
|
|
"unexpected type for struct literal: {:?}",
|
|
expr_ty);
|
|
}
|
|
}
|
|
}
|
|
|
|
hir::ExprKind::Closure(..) => {
|
|
let closure_ty = cx.tables().expr_ty(expr);
|
|
let (def_id, substs, movability) = match closure_ty.sty {
|
|
ty::Closure(def_id, substs) => (def_id, UpvarSubsts::Closure(substs), None),
|
|
ty::Generator(def_id, substs, movability) => {
|
|
(def_id, UpvarSubsts::Generator(substs), Some(movability))
|
|
}
|
|
_ => {
|
|
span_bug!(expr.span, "closure expr w/o closure type: {:?}", closure_ty);
|
|
}
|
|
};
|
|
let upvars = cx.tcx.upvars(def_id).iter()
|
|
.flat_map(|upvars| upvars.iter())
|
|
.zip(substs.upvar_tys(def_id, cx.tcx))
|
|
.map(|(upvar, ty)| capture_upvar(cx, expr, upvar, ty))
|
|
.collect();
|
|
ExprKind::Closure {
|
|
closure_id: def_id,
|
|
substs,
|
|
upvars,
|
|
movability,
|
|
}
|
|
}
|
|
|
|
hir::ExprKind::Path(ref qpath) => {
|
|
let res = cx.tables().qpath_res(qpath, expr.hir_id);
|
|
convert_path_expr(cx, expr, res)
|
|
}
|
|
|
|
hir::ExprKind::InlineAsm(ref asm, ref outputs, ref inputs) => {
|
|
ExprKind::InlineAsm {
|
|
asm,
|
|
outputs: outputs.to_ref(),
|
|
inputs: inputs.to_ref(),
|
|
}
|
|
}
|
|
|
|
// Now comes the rote stuff:
|
|
hir::ExprKind::Repeat(ref v, ref count) => {
|
|
let def_id = cx.tcx.hir().local_def_id_from_hir_id(count.hir_id);
|
|
let substs = InternalSubsts::identity_for_item(cx.tcx.global_tcx(), def_id);
|
|
let instance = ty::Instance::resolve(
|
|
cx.tcx.global_tcx(),
|
|
cx.param_env,
|
|
def_id,
|
|
substs,
|
|
).unwrap();
|
|
let global_id = GlobalId {
|
|
instance,
|
|
promoted: None
|
|
};
|
|
let span = cx.tcx.def_span(def_id);
|
|
let count = match cx.tcx.at(span).const_eval(cx.param_env.and(global_id)) {
|
|
Ok(cv) => cv.unwrap_usize(cx.tcx),
|
|
Err(ErrorHandled::Reported) => 0,
|
|
Err(ErrorHandled::TooGeneric) => {
|
|
cx.tcx.sess.span_err(span, "array lengths can't depend on generic parameters");
|
|
0
|
|
},
|
|
};
|
|
|
|
ExprKind::Repeat {
|
|
value: v.to_ref(),
|
|
count,
|
|
}
|
|
}
|
|
hir::ExprKind::Ret(ref v) => ExprKind::Return { value: v.to_ref() },
|
|
hir::ExprKind::Break(dest, ref value) => {
|
|
match dest.target_id {
|
|
Ok(target_id) => ExprKind::Break {
|
|
label: region::Scope {
|
|
id: target_id.local_id,
|
|
data: region::ScopeData::Node
|
|
},
|
|
value: value.to_ref(),
|
|
},
|
|
Err(err) => bug!("invalid loop id for break: {}", err)
|
|
}
|
|
}
|
|
hir::ExprKind::Continue(dest) => {
|
|
match dest.target_id {
|
|
Ok(loop_id) => ExprKind::Continue {
|
|
label: region::Scope {
|
|
id: loop_id.local_id,
|
|
data: region::ScopeData::Node
|
|
},
|
|
},
|
|
Err(err) => bug!("invalid loop id for continue: {}", err)
|
|
}
|
|
}
|
|
hir::ExprKind::Match(ref discr, ref arms, _) => {
|
|
ExprKind::Match {
|
|
scrutinee: discr.to_ref(),
|
|
arms: arms.iter().map(|a| convert_arm(cx, a)).collect(),
|
|
}
|
|
}
|
|
hir::ExprKind::While(ref cond, ref body, _) => {
|
|
ExprKind::Loop {
|
|
condition: Some(cond.to_ref()),
|
|
body: block::to_expr_ref(cx, body),
|
|
}
|
|
}
|
|
hir::ExprKind::Loop(ref body, _, _) => {
|
|
ExprKind::Loop {
|
|
condition: None,
|
|
body: block::to_expr_ref(cx, body),
|
|
}
|
|
}
|
|
hir::ExprKind::Field(ref source, ..) => {
|
|
ExprKind::Field {
|
|
lhs: source.to_ref(),
|
|
name: Field::new(cx.tcx.field_index(expr.hir_id, cx.tables)),
|
|
}
|
|
}
|
|
hir::ExprKind::Cast(ref source, ref cast_ty) => {
|
|
// Check for a user-given type annotation on this `cast`
|
|
let user_provided_types = cx.tables.user_provided_types();
|
|
let user_ty = user_provided_types.get(cast_ty.hir_id);
|
|
|
|
debug!(
|
|
"cast({:?}) has ty w/ hir_id {:?} and user provided ty {:?}",
|
|
expr,
|
|
cast_ty.hir_id,
|
|
user_ty,
|
|
);
|
|
|
|
// Check to see if this cast is a "coercion cast", where the cast is actually done
|
|
// using a coercion (or is a no-op).
|
|
let cast = if cx.tables().is_coercion_cast(source.hir_id) {
|
|
// Convert the lexpr to a vexpr.
|
|
ExprKind::Use { source: source.to_ref() }
|
|
} else {
|
|
// check whether this is casting an enum variant discriminant
|
|
// to prevent cycles, we refer to the discriminant initializer
|
|
// which is always an integer and thus doesn't need to know the
|
|
// enum's layout (or its tag type) to compute it during const eval
|
|
// Example:
|
|
// enum Foo {
|
|
// A,
|
|
// B = A as isize + 4,
|
|
// }
|
|
// The correct solution would be to add symbolic computations to miri,
|
|
// so we wouldn't have to compute and store the actual value
|
|
let var = if let hir::ExprKind::Path(ref qpath) = source.node {
|
|
let res = cx.tables().qpath_res(qpath, source.hir_id);
|
|
cx
|
|
.tables()
|
|
.node_type(source.hir_id)
|
|
.ty_adt_def()
|
|
.and_then(|adt_def| {
|
|
match res {
|
|
Res::Def(
|
|
DefKind::Ctor(CtorOf::Variant, CtorKind::Const),
|
|
variant_ctor_id,
|
|
) => {
|
|
let idx = adt_def.variant_index_with_ctor_id(variant_ctor_id);
|
|
let (d, o) = adt_def.discriminant_def_for_variant(idx);
|
|
use rustc::ty::util::IntTypeExt;
|
|
let ty = adt_def.repr.discr_type();
|
|
let ty = ty.to_ty(cx.tcx());
|
|
Some((d, o, ty))
|
|
}
|
|
_ => None,
|
|
}
|
|
})
|
|
} else {
|
|
None
|
|
};
|
|
|
|
let source = if let Some((did, offset, var_ty)) = var {
|
|
let mk_const = |literal| Expr {
|
|
temp_lifetime,
|
|
ty: var_ty,
|
|
span: expr.span,
|
|
kind: ExprKind::Literal {
|
|
literal,
|
|
user_ty: None
|
|
},
|
|
}.to_ref();
|
|
let offset = mk_const(ty::Const::from_bits(
|
|
cx.tcx,
|
|
offset as u128,
|
|
cx.param_env.and(var_ty),
|
|
));
|
|
match did {
|
|
Some(did) => {
|
|
// in case we are offsetting from a computed discriminant
|
|
// and not the beginning of discriminants (which is always `0`)
|
|
let substs = InternalSubsts::identity_for_item(cx.tcx(), did);
|
|
let lhs = mk_const(cx.tcx().mk_const(ty::Const {
|
|
val: ConstValue::Unevaluated(did, substs),
|
|
ty: var_ty,
|
|
}));
|
|
let bin = ExprKind::Binary {
|
|
op: BinOp::Add,
|
|
lhs,
|
|
rhs: offset,
|
|
};
|
|
Expr {
|
|
temp_lifetime,
|
|
ty: var_ty,
|
|
span: expr.span,
|
|
kind: bin,
|
|
}.to_ref()
|
|
},
|
|
None => offset,
|
|
}
|
|
} else {
|
|
source.to_ref()
|
|
};
|
|
|
|
ExprKind::Cast { source }
|
|
};
|
|
|
|
if let Some(user_ty) = user_ty {
|
|
// NOTE: Creating a new Expr and wrapping a Cast inside of it may be
|
|
// inefficient, revisit this when performance becomes an issue.
|
|
let cast_expr = Expr {
|
|
temp_lifetime,
|
|
ty: expr_ty,
|
|
span: expr.span,
|
|
kind: cast,
|
|
};
|
|
debug!("make_mirror_unadjusted: (cast) user_ty={:?}", user_ty);
|
|
|
|
ExprKind::ValueTypeAscription {
|
|
source: cast_expr.to_ref(),
|
|
user_ty: Some(*user_ty),
|
|
}
|
|
} else {
|
|
cast
|
|
}
|
|
}
|
|
hir::ExprKind::Type(ref source, ref ty) => {
|
|
let user_provided_types = cx.tables.user_provided_types();
|
|
let user_ty = user_provided_types.get(ty.hir_id).map(|u_ty| *u_ty);
|
|
debug!("make_mirror_unadjusted: (type) user_ty={:?}", user_ty);
|
|
if source.is_place_expr() {
|
|
ExprKind::PlaceTypeAscription {
|
|
source: source.to_ref(),
|
|
user_ty,
|
|
}
|
|
} else {
|
|
ExprKind::ValueTypeAscription {
|
|
source: source.to_ref(),
|
|
user_ty,
|
|
}
|
|
}
|
|
}
|
|
hir::ExprKind::DropTemps(ref source) => {
|
|
ExprKind::Use { source: source.to_ref() }
|
|
}
|
|
hir::ExprKind::Box(ref value) => {
|
|
ExprKind::Box {
|
|
value: value.to_ref(),
|
|
}
|
|
}
|
|
hir::ExprKind::Array(ref fields) => ExprKind::Array { fields: fields.to_ref() },
|
|
hir::ExprKind::Tup(ref fields) => ExprKind::Tuple { fields: fields.to_ref() },
|
|
|
|
hir::ExprKind::Yield(ref v) => ExprKind::Yield { value: v.to_ref() },
|
|
hir::ExprKind::Err => unreachable!(),
|
|
};
|
|
|
|
Expr {
|
|
temp_lifetime,
|
|
ty: expr_ty,
|
|
span: expr.span,
|
|
kind,
|
|
}
|
|
}
|
|
|
|
fn user_substs_applied_to_res(
|
|
cx: &mut Cx<'a, 'gcx, 'tcx>,
|
|
hir_id: hir::HirId,
|
|
res: Res,
|
|
) -> Option<ty::CanonicalUserType<'tcx>> {
|
|
debug!("user_substs_applied_to_res: res={:?}", res);
|
|
let user_provided_type = match res {
|
|
// A reference to something callable -- e.g., a fn, method, or
|
|
// a tuple-struct or tuple-variant. This has the type of a
|
|
// `Fn` but with the user-given substitutions.
|
|
Res::Def(DefKind::Fn, _) |
|
|
Res::Def(DefKind::Method, _) |
|
|
Res::Def(DefKind::Ctor(_, CtorKind::Fn), _) |
|
|
Res::Def(DefKind::Const, _) |
|
|
Res::Def(DefKind::AssocConst, _) =>
|
|
cx.tables().user_provided_types().get(hir_id).map(|u_ty| *u_ty),
|
|
|
|
// A unit struct/variant which is used as a value (e.g.,
|
|
// `None`). This has the type of the enum/struct that defines
|
|
// this variant -- but with the substitutions given by the
|
|
// user.
|
|
Res::Def(DefKind::Ctor(_, CtorKind::Const), _) =>
|
|
cx.user_substs_applied_to_ty_of_hir_id(hir_id),
|
|
|
|
// `Self` is used in expression as a tuple struct constructor or an unit struct constructor
|
|
Res::SelfCtor(_) =>
|
|
cx.user_substs_applied_to_ty_of_hir_id(hir_id),
|
|
|
|
_ =>
|
|
bug!("user_substs_applied_to_res: unexpected res {:?} at {:?}", res, hir_id)
|
|
};
|
|
debug!("user_substs_applied_to_res: user_provided_type={:?}", user_provided_type);
|
|
user_provided_type
|
|
}
|
|
|
|
fn method_callee<'a, 'gcx, 'tcx>(
|
|
cx: &mut Cx<'a, 'gcx, 'tcx>,
|
|
expr: &hir::Expr,
|
|
span: Span,
|
|
overloaded_callee: Option<(DefId, SubstsRef<'tcx>)>,
|
|
) -> Expr<'tcx> {
|
|
let temp_lifetime = cx.region_scope_tree.temporary_scope(expr.hir_id.local_id);
|
|
let (def_id, substs, user_ty) = match overloaded_callee {
|
|
Some((def_id, substs)) => (def_id, substs, None),
|
|
None => {
|
|
let (kind, def_id) = cx.tables().type_dependent_def(expr.hir_id)
|
|
.unwrap_or_else(|| {
|
|
span_bug!(expr.span, "no type-dependent def for method callee")
|
|
});
|
|
let user_ty = user_substs_applied_to_res(cx, expr.hir_id, Res::Def(kind, def_id));
|
|
debug!("method_callee: user_ty={:?}", user_ty);
|
|
(def_id, cx.tables().node_substs(expr.hir_id), user_ty)
|
|
}
|
|
};
|
|
let ty = cx.tcx().mk_fn_def(def_id, substs);
|
|
Expr {
|
|
temp_lifetime,
|
|
ty,
|
|
span,
|
|
kind: ExprKind::Literal {
|
|
literal: ty::Const::zero_sized(cx.tcx(), ty),
|
|
user_ty,
|
|
},
|
|
}
|
|
}
|
|
|
|
trait ToBorrowKind { fn to_borrow_kind(&self) -> BorrowKind; }
|
|
|
|
impl ToBorrowKind for AutoBorrowMutability {
|
|
fn to_borrow_kind(&self) -> BorrowKind {
|
|
use rustc::ty::adjustment::AllowTwoPhase;
|
|
match *self {
|
|
AutoBorrowMutability::Mutable { allow_two_phase_borrow } =>
|
|
BorrowKind::Mut { allow_two_phase_borrow: match allow_two_phase_borrow {
|
|
AllowTwoPhase::Yes => true,
|
|
AllowTwoPhase::No => false
|
|
}},
|
|
AutoBorrowMutability::Immutable =>
|
|
BorrowKind::Shared,
|
|
}
|
|
}
|
|
}
|
|
|
|
impl ToBorrowKind for hir::Mutability {
|
|
fn to_borrow_kind(&self) -> BorrowKind {
|
|
match *self {
|
|
hir::MutMutable => BorrowKind::Mut { allow_two_phase_borrow: false },
|
|
hir::MutImmutable => BorrowKind::Shared,
|
|
}
|
|
}
|
|
}
|
|
|
|
fn convert_arm<'a, 'gcx, 'tcx>(cx: &mut Cx<'a, 'gcx, 'tcx>, arm: &'tcx hir::Arm) -> Arm<'tcx> {
|
|
Arm {
|
|
patterns: arm.pats.iter().map(|p| cx.pattern_from_hir(p)).collect(),
|
|
guard: match arm.guard {
|
|
Some(hir::Guard::If(ref e)) => Some(Guard::If(e.to_ref())),
|
|
_ => None,
|
|
},
|
|
body: arm.body.to_ref(),
|
|
lint_level: LintLevel::Explicit(arm.hir_id),
|
|
scope: region::Scope {
|
|
id: arm.hir_id.local_id,
|
|
data: region::ScopeData::Node
|
|
},
|
|
span: arm.span,
|
|
}
|
|
}
|
|
|
|
fn convert_path_expr<'a, 'gcx, 'tcx>(cx: &mut Cx<'a, 'gcx, 'tcx>,
|
|
expr: &'tcx hir::Expr,
|
|
res: Res)
|
|
-> ExprKind<'tcx> {
|
|
let substs = cx.tables().node_substs(expr.hir_id);
|
|
match res {
|
|
// A regular function, constructor function or a constant.
|
|
Res::Def(DefKind::Fn, _) |
|
|
Res::Def(DefKind::Method, _) |
|
|
Res::Def(DefKind::Ctor(_, CtorKind::Fn), _) |
|
|
Res::SelfCtor(..) => {
|
|
let user_ty = user_substs_applied_to_res(cx, expr.hir_id, res);
|
|
debug!("convert_path_expr: user_ty={:?}", user_ty);
|
|
ExprKind::Literal {
|
|
literal: ty::Const::zero_sized(
|
|
cx.tcx,
|
|
cx.tables().node_type(expr.hir_id),
|
|
),
|
|
user_ty,
|
|
}
|
|
}
|
|
|
|
Res::Def(DefKind::ConstParam, def_id) => {
|
|
let node_id = cx.tcx.hir().as_local_node_id(def_id).unwrap();
|
|
let item_id = cx.tcx.hir().get_parent_node(node_id);
|
|
let item_def_id = cx.tcx.hir().local_def_id(item_id);
|
|
let generics = cx.tcx.generics_of(item_def_id);
|
|
let index = generics.param_def_id_to_index[&cx.tcx.hir().local_def_id(node_id)];
|
|
let name = cx.tcx.hir().name(node_id).as_interned_str();
|
|
let val = ConstValue::Param(ty::ParamConst::new(index, name));
|
|
ExprKind::Literal {
|
|
literal: cx.tcx.mk_const(
|
|
ty::Const {
|
|
val,
|
|
ty: cx.tables().node_type(expr.hir_id),
|
|
}
|
|
),
|
|
user_ty: None,
|
|
}
|
|
}
|
|
|
|
Res::Def(DefKind::Const, def_id) |
|
|
Res::Def(DefKind::AssocConst, def_id) => {
|
|
let user_ty = user_substs_applied_to_res(cx, expr.hir_id, res);
|
|
debug!("convert_path_expr: (const) user_ty={:?}", user_ty);
|
|
ExprKind::Literal {
|
|
literal: cx.tcx.mk_const(ty::Const {
|
|
val: ConstValue::Unevaluated(def_id, substs),
|
|
ty: cx.tcx.type_of(def_id),
|
|
}),
|
|
user_ty,
|
|
}
|
|
},
|
|
|
|
Res::Def(DefKind::Ctor(_, CtorKind::Const), def_id) => {
|
|
let user_provided_types = cx.tables.user_provided_types();
|
|
let user_provided_type = user_provided_types.get(expr.hir_id).map(|u_ty| *u_ty);
|
|
debug!("convert_path_expr: user_provided_type={:?}", user_provided_type);
|
|
let ty = cx.tables().node_type(expr.hir_id);
|
|
match ty.sty {
|
|
// A unit struct/variant which is used as a value.
|
|
// We return a completely different ExprKind here to account for this special case.
|
|
ty::Adt(adt_def, substs) => {
|
|
ExprKind::Adt {
|
|
adt_def,
|
|
variant_index: adt_def.variant_index_with_ctor_id(def_id),
|
|
substs,
|
|
user_ty: user_provided_type,
|
|
fields: vec![],
|
|
base: None,
|
|
}
|
|
}
|
|
_ => bug!("unexpected ty: {:?}", ty),
|
|
}
|
|
}
|
|
|
|
Res::Def(DefKind::Static, id) => ExprKind::StaticRef { id },
|
|
|
|
Res::Local(var_hir_id) => convert_var(cx, expr, var_hir_id),
|
|
Res::Upvar(var_hir_id, closure_node_id) => {
|
|
let closure_def_id = cx.tcx.hir().local_def_id(closure_node_id);
|
|
assert_eq!(cx.body_owner, closure_def_id);
|
|
assert!(cx.upvar_indices.contains_key(&var_hir_id));
|
|
|
|
convert_var(cx, expr, var_hir_id)
|
|
}
|
|
|
|
_ => span_bug!(expr.span, "res `{:?}` not yet implemented", res),
|
|
}
|
|
}
|
|
|
|
fn convert_var(
|
|
cx: &mut Cx<'_, '_, 'tcx>,
|
|
expr: &'tcx hir::Expr,
|
|
var_hir_id: hir::HirId,
|
|
) -> ExprKind<'tcx> {
|
|
let upvar_index = cx.upvar_indices.get(&var_hir_id).cloned();
|
|
|
|
debug!("convert_var({:?}): upvar_index={:?}, body_owner={:?}",
|
|
var_hir_id, upvar_index, cx.body_owner);
|
|
|
|
let temp_lifetime = cx.region_scope_tree.temporary_scope(expr.hir_id.local_id);
|
|
|
|
match upvar_index {
|
|
None => ExprKind::VarRef { id: var_hir_id },
|
|
|
|
Some(upvar_index) => {
|
|
let closure_def_id = cx.body_owner;
|
|
let upvar_id = ty::UpvarId {
|
|
var_path: ty::UpvarPath {hir_id: var_hir_id},
|
|
closure_expr_id: LocalDefId::from_def_id(closure_def_id),
|
|
};
|
|
let var_ty = cx.tables().node_type(var_hir_id);
|
|
|
|
// FIXME free regions in closures are not right
|
|
let closure_ty = cx.tables().node_type(
|
|
cx.tcx.hir().local_def_id_to_hir_id(upvar_id.closure_expr_id),
|
|
);
|
|
|
|
// FIXME we're just hard-coding the idea that the
|
|
// signature will be &self or &mut self and hence will
|
|
// have a bound region with number 0
|
|
let region = ty::ReFree(ty::FreeRegion {
|
|
scope: closure_def_id,
|
|
bound_region: ty::BoundRegion::BrAnon(0),
|
|
});
|
|
let region = cx.tcx.mk_region(region);
|
|
|
|
let self_expr = if let ty::Closure(_, closure_substs) = closure_ty.sty {
|
|
match cx.infcx.closure_kind(closure_def_id, closure_substs).unwrap() {
|
|
ty::ClosureKind::Fn => {
|
|
let ref_closure_ty = cx.tcx.mk_ref(region,
|
|
ty::TypeAndMut {
|
|
ty: closure_ty,
|
|
mutbl: hir::MutImmutable,
|
|
});
|
|
Expr {
|
|
ty: closure_ty,
|
|
temp_lifetime: temp_lifetime,
|
|
span: expr.span,
|
|
kind: ExprKind::Deref {
|
|
arg: Expr {
|
|
ty: ref_closure_ty,
|
|
temp_lifetime,
|
|
span: expr.span,
|
|
kind: ExprKind::SelfRef,
|
|
}
|
|
.to_ref(),
|
|
},
|
|
}
|
|
}
|
|
ty::ClosureKind::FnMut => {
|
|
let ref_closure_ty = cx.tcx.mk_ref(region,
|
|
ty::TypeAndMut {
|
|
ty: closure_ty,
|
|
mutbl: hir::MutMutable,
|
|
});
|
|
Expr {
|
|
ty: closure_ty,
|
|
temp_lifetime,
|
|
span: expr.span,
|
|
kind: ExprKind::Deref {
|
|
arg: Expr {
|
|
ty: ref_closure_ty,
|
|
temp_lifetime,
|
|
span: expr.span,
|
|
kind: ExprKind::SelfRef,
|
|
}.to_ref(),
|
|
},
|
|
}
|
|
}
|
|
ty::ClosureKind::FnOnce => {
|
|
Expr {
|
|
ty: closure_ty,
|
|
temp_lifetime,
|
|
span: expr.span,
|
|
kind: ExprKind::SelfRef,
|
|
}
|
|
}
|
|
}
|
|
} else {
|
|
Expr {
|
|
ty: closure_ty,
|
|
temp_lifetime,
|
|
span: expr.span,
|
|
kind: ExprKind::SelfRef,
|
|
}
|
|
};
|
|
|
|
// at this point we have `self.n`, which loads up the upvar
|
|
let field_kind = ExprKind::Field {
|
|
lhs: self_expr.to_ref(),
|
|
name: Field::new(upvar_index),
|
|
};
|
|
|
|
// ...but the upvar might be an `&T` or `&mut T` capture, at which
|
|
// point we need an implicit deref
|
|
match cx.tables().upvar_capture(upvar_id) {
|
|
ty::UpvarCapture::ByValue => field_kind,
|
|
ty::UpvarCapture::ByRef(borrow) => {
|
|
ExprKind::Deref {
|
|
arg: Expr {
|
|
temp_lifetime,
|
|
ty: cx.tcx.mk_ref(borrow.region,
|
|
ty::TypeAndMut {
|
|
ty: var_ty,
|
|
mutbl: borrow.kind.to_mutbl_lossy(),
|
|
}),
|
|
span: expr.span,
|
|
kind: field_kind,
|
|
}.to_ref(),
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
fn bin_op(op: hir::BinOpKind) -> BinOp {
|
|
match op {
|
|
hir::BinOpKind::Add => BinOp::Add,
|
|
hir::BinOpKind::Sub => BinOp::Sub,
|
|
hir::BinOpKind::Mul => BinOp::Mul,
|
|
hir::BinOpKind::Div => BinOp::Div,
|
|
hir::BinOpKind::Rem => BinOp::Rem,
|
|
hir::BinOpKind::BitXor => BinOp::BitXor,
|
|
hir::BinOpKind::BitAnd => BinOp::BitAnd,
|
|
hir::BinOpKind::BitOr => BinOp::BitOr,
|
|
hir::BinOpKind::Shl => BinOp::Shl,
|
|
hir::BinOpKind::Shr => BinOp::Shr,
|
|
hir::BinOpKind::Eq => BinOp::Eq,
|
|
hir::BinOpKind::Lt => BinOp::Lt,
|
|
hir::BinOpKind::Le => BinOp::Le,
|
|
hir::BinOpKind::Ne => BinOp::Ne,
|
|
hir::BinOpKind::Ge => BinOp::Ge,
|
|
hir::BinOpKind::Gt => BinOp::Gt,
|
|
_ => bug!("no equivalent for ast binop {:?}", op),
|
|
}
|
|
}
|
|
|
|
fn overloaded_operator<'a, 'gcx, 'tcx>(cx: &mut Cx<'a, 'gcx, 'tcx>,
|
|
expr: &'tcx hir::Expr,
|
|
args: Vec<ExprRef<'tcx>>)
|
|
-> ExprKind<'tcx> {
|
|
let fun = method_callee(cx, expr, expr.span, None);
|
|
ExprKind::Call {
|
|
ty: fun.ty,
|
|
fun: fun.to_ref(),
|
|
args,
|
|
from_hir_call: false,
|
|
}
|
|
}
|
|
|
|
fn overloaded_place<'a, 'gcx, 'tcx>(
|
|
cx: &mut Cx<'a, 'gcx, 'tcx>,
|
|
expr: &'tcx hir::Expr,
|
|
place_ty: Ty<'tcx>,
|
|
overloaded_callee: Option<(DefId, SubstsRef<'tcx>)>,
|
|
args: Vec<ExprRef<'tcx>>,
|
|
) -> ExprKind<'tcx> {
|
|
// For an overloaded *x or x[y] expression of type T, the method
|
|
// call returns an &T and we must add the deref so that the types
|
|
// line up (this is because `*x` and `x[y]` represent places):
|
|
|
|
let recv_ty = match args[0] {
|
|
ExprRef::Hair(e) => cx.tables().expr_ty_adjusted(e),
|
|
ExprRef::Mirror(ref e) => e.ty
|
|
};
|
|
|
|
// Reconstruct the output assuming it's a reference with the
|
|
// same region and mutability as the receiver. This holds for
|
|
// `Deref(Mut)::Deref(_mut)` and `Index(Mut)::index(_mut)`.
|
|
let (region, mutbl) = match recv_ty.sty {
|
|
ty::Ref(region, _, mutbl) => (region, mutbl),
|
|
_ => span_bug!(expr.span, "overloaded_place: receiver is not a reference"),
|
|
};
|
|
let ref_ty = cx.tcx.mk_ref(region, ty::TypeAndMut {
|
|
ty: place_ty,
|
|
mutbl,
|
|
});
|
|
|
|
// construct the complete expression `foo()` for the overloaded call,
|
|
// which will yield the &T type
|
|
let temp_lifetime = cx.region_scope_tree.temporary_scope(expr.hir_id.local_id);
|
|
let fun = method_callee(cx, expr, expr.span, overloaded_callee);
|
|
let ref_expr = Expr {
|
|
temp_lifetime,
|
|
ty: ref_ty,
|
|
span: expr.span,
|
|
kind: ExprKind::Call {
|
|
ty: fun.ty,
|
|
fun: fun.to_ref(),
|
|
args,
|
|
from_hir_call: false,
|
|
},
|
|
};
|
|
|
|
// construct and return a deref wrapper `*foo()`
|
|
ExprKind::Deref { arg: ref_expr.to_ref() }
|
|
}
|
|
|
|
fn capture_upvar<'a, 'gcx, 'tcx>(cx: &mut Cx<'a, 'gcx, 'tcx>,
|
|
closure_expr: &'tcx hir::Expr,
|
|
upvar: &hir::Upvar,
|
|
upvar_ty: Ty<'tcx>)
|
|
-> ExprRef<'tcx> {
|
|
let upvar_id = ty::UpvarId {
|
|
var_path: ty::UpvarPath { hir_id: upvar.var_id },
|
|
closure_expr_id: cx.tcx.hir().local_def_id_from_hir_id(closure_expr.hir_id).to_local(),
|
|
};
|
|
let upvar_capture = cx.tables().upvar_capture(upvar_id);
|
|
let temp_lifetime = cx.region_scope_tree.temporary_scope(closure_expr.hir_id.local_id);
|
|
let var_ty = cx.tables().node_type(upvar.var_id);
|
|
if upvar.has_parent {
|
|
let closure_def_id = upvar_id.closure_expr_id.to_def_id();
|
|
assert_eq!(cx.body_owner, cx.tcx.parent(closure_def_id).unwrap());
|
|
}
|
|
assert_eq!(upvar.has_parent, cx.upvar_indices.contains_key(&upvar.var_id));
|
|
let captured_var = Expr {
|
|
temp_lifetime,
|
|
ty: var_ty,
|
|
span: closure_expr.span,
|
|
kind: convert_var(cx, closure_expr, upvar.var_id),
|
|
};
|
|
match upvar_capture {
|
|
ty::UpvarCapture::ByValue => captured_var.to_ref(),
|
|
ty::UpvarCapture::ByRef(upvar_borrow) => {
|
|
let borrow_kind = match upvar_borrow.kind {
|
|
ty::BorrowKind::ImmBorrow => BorrowKind::Shared,
|
|
ty::BorrowKind::UniqueImmBorrow => BorrowKind::Unique,
|
|
ty::BorrowKind::MutBorrow => BorrowKind::Mut { allow_two_phase_borrow: false }
|
|
};
|
|
Expr {
|
|
temp_lifetime,
|
|
ty: upvar_ty,
|
|
span: closure_expr.span,
|
|
kind: ExprKind::Borrow {
|
|
borrow_kind,
|
|
arg: captured_var.to_ref(),
|
|
},
|
|
}.to_ref()
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Converts a list of named fields (i.e., for struct-like struct/enum ADTs) into FieldExprRef.
|
|
fn field_refs<'a, 'gcx, 'tcx>(cx: &mut Cx<'a, 'gcx, 'tcx>,
|
|
fields: &'tcx [hir::Field])
|
|
-> Vec<FieldExprRef<'tcx>> {
|
|
fields.iter()
|
|
.map(|field| {
|
|
FieldExprRef {
|
|
name: Field::new(cx.tcx.field_index(field.hir_id, cx.tables)),
|
|
expr: field.expr.to_ref(),
|
|
}
|
|
})
|
|
.collect()
|
|
}
|