1 use crate::thir::cx::Cx;
2 use crate::thir::util::UserAnnotatedTyHelpers;
3 use rustc_data_structures::stack::ensure_sufficient_stack;
5 use rustc_hir::def::{CtorKind, CtorOf, DefKind, Res};
6 use rustc_index::vec::Idx;
7 use rustc_middle::hir::place::Place as HirPlace;
8 use rustc_middle::hir::place::PlaceBase as HirPlaceBase;
9 use rustc_middle::hir::place::ProjectionKind as HirProjectionKind;
10 use rustc_middle::middle::region;
11 use rustc_middle::mir::{BinOp, BorrowKind, Field, UnOp};
12 use rustc_middle::thir::*;
13 use rustc_middle::ty::adjustment::{
14 Adjust, Adjustment, AutoBorrow, AutoBorrowMutability, PointerCast,
16 use rustc_middle::ty::subst::{InternalSubsts, SubstsRef};
17 use rustc_middle::ty::{self, AdtKind, Ty, UpvarSubsts, UserType};
18 use rustc_span::def_id::DefId;
20 use rustc_target::abi::VariantIdx;
23 crate fn mirror_expr(&mut self, expr: &'tcx hir::Expr<'tcx>) -> ExprId {
24 // `mirror_expr` is recursing very deep. Make sure the stack doesn't overflow.
25 ensure_sufficient_stack(|| self.mirror_expr_inner(expr))
28 crate fn mirror_exprs(&mut self, exprs: &'tcx [hir::Expr<'tcx>]) -> Box<[ExprId]> {
29 exprs.iter().map(|expr| self.mirror_expr_inner(expr)).collect()
32 pub(super) fn mirror_expr_inner(&mut self, hir_expr: &'tcx hir::Expr<'tcx>) -> ExprId {
33 let temp_lifetime = self.region_scope_tree.temporary_scope(hir_expr.hir_id.local_id);
35 region::Scope { id: hir_expr.hir_id.local_id, data: region::ScopeData::Node };
37 debug!("Expr::make_mirror(): id={}, span={:?}", hir_expr.hir_id, hir_expr.span);
39 let mut expr = self.make_mirror_unadjusted(hir_expr);
41 let adjustment_span = match self.adjustment_span {
42 Some((hir_id, span)) if hir_id == hir_expr.hir_id => Some(span),
46 // Now apply adjustments, if any.
47 for adjustment in self.typeck_results.expr_adjustments(hir_expr) {
48 debug!("make_mirror: expr={:?} applying adjustment={:?}", expr, adjustment);
51 self.apply_adjustment(hir_expr, expr, adjustment, adjustment_span.unwrap_or(span));
54 // Next, wrap this up in the expr's scope.
59 kind: ExprKind::Scope {
60 region_scope: expr_scope,
61 value: self.thir.exprs.push(expr),
62 lint_level: LintLevel::Explicit(hir_expr.hir_id),
66 // Finally, create a destruction scope, if any.
67 if let Some(region_scope) =
68 self.region_scope_tree.opt_destruction_scope(hir_expr.hir_id.local_id)
74 kind: ExprKind::Scope {
76 value: self.thir.exprs.push(expr),
77 lint_level: LintLevel::Inherited,
83 self.thir.exprs.push(expr)
88 hir_expr: &'tcx hir::Expr<'tcx>,
90 adjustment: &Adjustment<'tcx>,
93 let Expr { temp_lifetime, .. } = expr;
95 // Adjust the span from the block, to the last expression of the
96 // block. This is a better span when returning a mutable reference
97 // with too short a lifetime. The error message will use the span
98 // from the assignment to the return place, which should only point
99 // at the returned value, not the entire function body.
101 // fn return_short_lived<'a>(x: &'a mut i32) -> &'static mut i32 {
103 // // ^ error message points at this expression.
105 let mut adjust_span = |expr: &mut Expr<'tcx>| {
106 if let ExprKind::Block { body } = &expr.kind {
107 if let Some(last_expr) = body.expr {
108 span = self.thir[last_expr].span;
114 let kind = match adjustment.kind {
115 Adjust::Pointer(PointerCast::Unsize) => {
116 adjust_span(&mut expr);
117 ExprKind::Pointer { cast: PointerCast::Unsize, source: self.thir.exprs.push(expr) }
119 Adjust::Pointer(cast) => ExprKind::Pointer { cast, source: self.thir.exprs.push(expr) },
120 Adjust::NeverToAny => ExprKind::NeverToAny { source: self.thir.exprs.push(expr) },
121 Adjust::Deref(None) => {
122 adjust_span(&mut expr);
123 ExprKind::Deref { arg: self.thir.exprs.push(expr) }
125 Adjust::Deref(Some(deref)) => {
126 // We don't need to do call adjust_span here since
127 // deref coercions always start with a built-in deref.
128 let call = deref.method_call(self.tcx(), expr.ty);
134 .mk_ref(deref.region, ty::TypeAndMut { ty: expr.ty, mutbl: deref.mutbl }),
136 kind: ExprKind::Borrow {
137 borrow_kind: deref.mutbl.to_borrow_kind(),
138 arg: self.thir.exprs.push(expr),
142 let expr = Box::new([self.thir.exprs.push(expr)]);
144 self.overloaded_place(hir_expr, adjustment.target, Some(call), expr, deref.span)
146 Adjust::Borrow(AutoBorrow::Ref(_, m)) => ExprKind::Borrow {
147 borrow_kind: m.to_borrow_kind(),
148 arg: self.thir.exprs.push(expr),
150 Adjust::Borrow(AutoBorrow::RawPtr(mutability)) => {
151 ExprKind::AddressOf { mutability, arg: self.thir.exprs.push(expr) }
155 Expr { temp_lifetime, ty: adjustment.target, span, kind }
158 fn make_mirror_unadjusted(&mut self, expr: &'tcx hir::Expr<'tcx>) -> Expr<'tcx> {
159 let expr_ty = self.typeck_results().expr_ty(expr);
160 let expr_span = expr.span;
161 let temp_lifetime = self.region_scope_tree.temporary_scope(expr.hir_id.local_id);
163 let kind = match expr.kind {
164 // Here comes the interesting stuff:
165 hir::ExprKind::MethodCall(segment, ref args, fn_span) => {
166 // Rewrite a.b(c) into UFCS form like Trait::b(a, c)
167 let expr = self.method_callee(expr, segment.ident.span, None);
168 // When we apply adjustments to the receiver, use the span of
169 // the overall method call for better diagnostics. args[0]
170 // is guaranteed to exist, since a method call always has a receiver.
171 let old_adjustment_span = self.adjustment_span.replace((args[0].hir_id, expr_span));
172 tracing::info!("Using method span: {:?}", expr.span);
173 let args = self.mirror_exprs(args);
174 self.adjustment_span = old_adjustment_span;
177 fun: self.thir.exprs.push(expr),
184 hir::ExprKind::Call(ref fun, ref args) => {
185 if self.typeck_results().is_method_call(expr) {
186 // The callee is something implementing Fn, FnMut, or FnOnce.
187 // Find the actual method implementation being called and
188 // build the appropriate UFCS call expression with the
189 // callee-object as expr parameter.
191 // rewrite f(u, v) into FnOnce::call_once(f, (u, v))
193 let method = self.method_callee(expr, fun.span, None);
195 let arg_tys = args.iter().map(|e| self.typeck_results().expr_ty_adjusted(e));
196 let tupled_args = Expr {
197 ty: self.tcx.mk_tup(arg_tys),
200 kind: ExprKind::Tuple { fields: self.mirror_exprs(args) },
202 let tupled_args = self.thir.exprs.push(tupled_args);
206 fun: self.thir.exprs.push(method),
207 args: Box::new([self.mirror_expr(fun), tupled_args]),
213 if let hir::ExprKind::Path(hir::QPath::Resolved(_, ref path)) = fun.kind {
214 // Tuple-like ADTs are represented as ExprKind::Call. We convert them here.
215 expr_ty.ty_adt_def().and_then(|adt_def| match path.res {
216 Res::Def(DefKind::Ctor(_, CtorKind::Fn), ctor_id) => {
217 Some((adt_def, adt_def.variant_index_with_ctor_id(ctor_id)))
219 Res::SelfCtor(..) => Some((adt_def, VariantIdx::new(0))),
225 if let Some((adt_def, index)) = adt_data {
226 let substs = self.typeck_results().node_substs(fun.hir_id);
227 let user_provided_types = self.typeck_results().user_provided_types();
229 user_provided_types.get(fun.hir_id).copied().map(|mut u_ty| {
230 if let UserType::TypeOf(ref mut did, _) = &mut u_ty.value {
235 debug!("make_mirror_unadjusted: (call) user_ty={:?}", user_ty);
237 let field_refs = args
240 .map(|(idx, e)| FieldExpr {
241 name: Field::new(idx),
242 expr: self.mirror_expr(e),
245 ExprKind::Adt(Box::new(Adt {
248 variant_index: index,
255 ty: self.typeck_results().node_type(fun.hir_id),
256 fun: self.mirror_expr(fun),
257 args: self.mirror_exprs(args),
265 hir::ExprKind::AddrOf(hir::BorrowKind::Ref, mutbl, ref arg) => {
266 ExprKind::Borrow { borrow_kind: mutbl.to_borrow_kind(), arg: self.mirror_expr(arg) }
269 hir::ExprKind::AddrOf(hir::BorrowKind::Raw, mutability, ref arg) => {
270 ExprKind::AddressOf { mutability, arg: self.mirror_expr(arg) }
273 hir::ExprKind::Block(ref blk, _) => ExprKind::Block { body: self.mirror_block(blk) },
275 hir::ExprKind::Assign(ref lhs, ref rhs, _) => {
276 ExprKind::Assign { lhs: self.mirror_expr(lhs), rhs: self.mirror_expr(rhs) }
279 hir::ExprKind::AssignOp(op, ref lhs, ref rhs) => {
280 if self.typeck_results().is_method_call(expr) {
281 let lhs = self.mirror_expr(lhs);
282 let rhs = self.mirror_expr(rhs);
283 self.overloaded_operator(expr, Box::new([lhs, rhs]))
287 lhs: self.mirror_expr(lhs),
288 rhs: self.mirror_expr(rhs),
293 hir::ExprKind::Lit(ref lit) => ExprKind::Literal {
294 literal: self.const_eval_literal(&lit.node, expr_ty, lit.span, false),
299 hir::ExprKind::Binary(op, ref lhs, ref rhs) => {
300 if self.typeck_results().is_method_call(expr) {
301 let lhs = self.mirror_expr(lhs);
302 let rhs = self.mirror_expr(rhs);
303 self.overloaded_operator(expr, Box::new([lhs, rhs]))
307 hir::BinOpKind::And => ExprKind::LogicalOp {
309 lhs: self.mirror_expr(lhs),
310 rhs: self.mirror_expr(rhs),
312 hir::BinOpKind::Or => ExprKind::LogicalOp {
314 lhs: self.mirror_expr(lhs),
315 rhs: self.mirror_expr(rhs),
318 let op = bin_op(op.node);
321 lhs: self.mirror_expr(lhs),
322 rhs: self.mirror_expr(rhs),
329 hir::ExprKind::Index(ref lhs, ref index) => {
330 if self.typeck_results().is_method_call(expr) {
331 let lhs = self.mirror_expr(lhs);
332 let index = self.mirror_expr(index);
333 self.overloaded_place(expr, expr_ty, None, Box::new([lhs, index]), expr.span)
335 ExprKind::Index { lhs: self.mirror_expr(lhs), index: self.mirror_expr(index) }
339 hir::ExprKind::Unary(hir::UnOp::Deref, ref arg) => {
340 if self.typeck_results().is_method_call(expr) {
341 let arg = self.mirror_expr(arg);
342 self.overloaded_place(expr, expr_ty, None, Box::new([arg]), expr.span)
344 ExprKind::Deref { arg: self.mirror_expr(arg) }
348 hir::ExprKind::Unary(hir::UnOp::Not, ref arg) => {
349 if self.typeck_results().is_method_call(expr) {
350 let arg = self.mirror_expr(arg);
351 self.overloaded_operator(expr, Box::new([arg]))
353 ExprKind::Unary { op: UnOp::Not, arg: self.mirror_expr(arg) }
357 hir::ExprKind::Unary(hir::UnOp::Neg, ref arg) => {
358 if self.typeck_results().is_method_call(expr) {
359 let arg = self.mirror_expr(arg);
360 self.overloaded_operator(expr, Box::new([arg]))
361 } else if let hir::ExprKind::Lit(ref lit) = arg.kind {
363 literal: self.const_eval_literal(&lit.node, expr_ty, lit.span, true),
368 ExprKind::Unary { op: UnOp::Neg, arg: self.mirror_expr(arg) }
372 hir::ExprKind::Struct(ref qpath, ref fields, ref base) => match expr_ty.kind() {
373 ty::Adt(adt, substs) => match adt.adt_kind() {
374 AdtKind::Struct | AdtKind::Union => {
375 let user_provided_types = self.typeck_results().user_provided_types();
376 let user_ty = user_provided_types.get(expr.hir_id).copied();
377 debug!("make_mirror_unadjusted: (struct/union) user_ty={:?}", user_ty);
378 ExprKind::Adt(Box::new(Adt {
380 variant_index: VariantIdx::new(0),
383 fields: self.field_refs(fields),
384 base: base.as_ref().map(|base| FruInfo {
385 base: self.mirror_expr(base),
386 field_types: self.typeck_results().fru_field_types()[expr.hir_id]
394 let res = self.typeck_results().qpath_res(qpath, expr.hir_id);
396 Res::Def(DefKind::Variant, variant_id) => {
397 assert!(base.is_none());
399 let index = adt.variant_index_with_id(variant_id);
400 let user_provided_types =
401 self.typeck_results().user_provided_types();
402 let user_ty = user_provided_types.get(expr.hir_id).copied();
403 debug!("make_mirror_unadjusted: (variant) user_ty={:?}", user_ty);
404 ExprKind::Adt(Box::new(Adt {
406 variant_index: index,
409 fields: self.field_refs(fields),
414 span_bug!(expr.span, "unexpected res: {:?}", res);
420 span_bug!(expr.span, "unexpected type for struct literal: {:?}", expr_ty);
424 hir::ExprKind::Closure(..) => {
425 let closure_ty = self.typeck_results().expr_ty(expr);
426 let (def_id, substs, movability) = match *closure_ty.kind() {
427 ty::Closure(def_id, substs) => (def_id, UpvarSubsts::Closure(substs), None),
428 ty::Generator(def_id, substs, movability) => {
429 (def_id, UpvarSubsts::Generator(substs), Some(movability))
432 span_bug!(expr.span, "closure expr w/o closure type: {:?}", closure_ty);
438 .closure_min_captures_flattened(def_id)
439 .zip(substs.upvar_tys())
440 .map(|(captured_place, ty)| {
441 let upvars = self.capture_upvar(expr, captured_place, ty);
442 self.thir.exprs.push(upvars)
446 // Convert the closure fake reads, if any, from hir `Place` to ExprRef
447 let fake_reads = match self.typeck_results.closure_fake_reads.get(&def_id) {
448 Some(fake_reads) => fake_reads
450 .map(|(place, cause, hir_id)| {
451 let expr = self.convert_captured_hir_place(expr, place.clone());
452 (self.thir.exprs.push(expr), *cause, *hir_id)
458 ExprKind::Closure { closure_id: def_id, substs, upvars, movability, fake_reads }
461 hir::ExprKind::Path(ref qpath) => {
462 let res = self.typeck_results().qpath_res(qpath, expr.hir_id);
463 self.convert_path_expr(expr, res)
466 hir::ExprKind::InlineAsm(ref asm) => ExprKind::InlineAsm {
467 template: asm.template,
471 .map(|(op, _op_sp)| {
473 hir::InlineAsmOperand::In { reg, ref expr } => {
474 InlineAsmOperand::In { reg, expr: self.mirror_expr(expr) }
476 hir::InlineAsmOperand::Out { reg, late, ref expr } => {
477 InlineAsmOperand::Out {
480 expr: expr.as_ref().map(|expr| self.mirror_expr(expr)),
483 hir::InlineAsmOperand::InOut { reg, late, ref expr } => {
484 InlineAsmOperand::InOut { reg, late, expr: self.mirror_expr(expr) }
486 hir::InlineAsmOperand::SplitInOut {
491 } => InlineAsmOperand::SplitInOut {
494 in_expr: self.mirror_expr(in_expr),
495 out_expr: out_expr.as_ref().map(|expr| self.mirror_expr(expr)),
497 hir::InlineAsmOperand::Const { ref anon_const } => {
498 let anon_const_def_id =
499 self.tcx.hir().local_def_id(anon_const.hir_id);
500 let value = ty::Const::from_anon_const(self.tcx, anon_const_def_id);
501 let span = self.tcx.hir().span(anon_const.hir_id);
503 InlineAsmOperand::Const { value, span }
505 hir::InlineAsmOperand::Sym { ref expr } => {
506 let hir::ExprKind::Path(ref qpath) = expr.kind else {
509 "asm `sym` operand should be a path, found {:?}",
514 self.region_scope_tree.temporary_scope(expr.hir_id.local_id);
515 let res = self.typeck_results().qpath_res(qpath, expr.hir_id);
518 Res::Def(DefKind::Fn, _) | Res::Def(DefKind::AssocFn, _) => {
519 ty = self.typeck_results().node_type(expr.hir_id);
521 self.user_substs_applied_to_res(expr.hir_id, res);
522 InlineAsmOperand::SymFn {
523 expr: self.thir.exprs.push(Expr {
527 kind: ExprKind::Literal {
528 literal: ty::Const::zero_sized(self.tcx, ty),
536 Res::Def(DefKind::Static, def_id) => {
537 InlineAsmOperand::SymStatic { def_id }
541 self.tcx.sess.span_err(
543 "asm `sym` operand must point to a fn or static",
546 // Not a real fn, but we're not reaching codegen anyways...
547 ty = self.tcx.ty_error();
548 InlineAsmOperand::SymFn {
549 expr: self.thir.exprs.push(Expr {
553 kind: ExprKind::Literal {
554 literal: ty::Const::zero_sized(self.tcx, ty),
566 options: asm.options,
567 line_spans: asm.line_spans,
570 hir::ExprKind::ConstBlock(ref anon_const) => {
571 let anon_const_def_id = self.tcx.hir().local_def_id(anon_const.hir_id);
572 let value = ty::Const::from_inline_const(self.tcx, anon_const_def_id);
574 ExprKind::ConstBlock { value }
576 // Now comes the rote stuff:
577 hir::ExprKind::Repeat(ref v, _) => {
578 let ty = self.typeck_results().expr_ty(expr);
579 let ty::Array(_, count) = ty.kind() else {
580 span_bug!(expr.span, "unexpected repeat expr ty: {:?}", ty);
583 ExprKind::Repeat { value: self.mirror_expr(v), count: *count }
585 hir::ExprKind::Ret(ref v) => {
586 ExprKind::Return { value: v.as_ref().map(|v| self.mirror_expr(v)) }
588 hir::ExprKind::Break(dest, ref value) => match dest.target_id {
589 Ok(target_id) => ExprKind::Break {
590 label: region::Scope { id: target_id.local_id, data: region::ScopeData::Node },
591 value: value.as_ref().map(|value| self.mirror_expr(value)),
593 Err(err) => bug!("invalid loop id for break: {}", err),
595 hir::ExprKind::Continue(dest) => match dest.target_id {
596 Ok(loop_id) => ExprKind::Continue {
597 label: region::Scope { id: loop_id.local_id, data: region::ScopeData::Node },
599 Err(err) => bug!("invalid loop id for continue: {}", err),
601 hir::ExprKind::Let(let_expr) => ExprKind::Let {
602 expr: self.mirror_expr(let_expr.init),
603 pat: self.pattern_from_hir(let_expr.pat),
605 hir::ExprKind::If(cond, then, else_opt) => ExprKind::If {
606 if_then_scope: region::Scope {
607 id: then.hir_id.local_id,
608 data: region::ScopeData::IfThen,
610 cond: self.mirror_expr(cond),
611 then: self.mirror_expr(then),
612 else_opt: else_opt.map(|el| self.mirror_expr(el)),
614 hir::ExprKind::Match(ref discr, ref arms, _) => ExprKind::Match {
615 scrutinee: self.mirror_expr(discr),
616 arms: arms.iter().map(|a| self.convert_arm(a)).collect(),
618 hir::ExprKind::Loop(ref body, ..) => {
619 let block_ty = self.typeck_results().node_type(body.hir_id);
620 let temp_lifetime = self.region_scope_tree.temporary_scope(body.hir_id.local_id);
621 let block = self.mirror_block(body);
622 let body = self.thir.exprs.push(Expr {
626 kind: ExprKind::Block { body: block },
628 ExprKind::Loop { body }
630 hir::ExprKind::Field(ref source, ..) => ExprKind::Field {
631 lhs: self.mirror_expr(source),
632 name: Field::new(self.tcx.field_index(expr.hir_id, self.typeck_results)),
634 hir::ExprKind::Cast(ref source, ref cast_ty) => {
635 // Check for a user-given type annotation on this `cast`
636 let user_provided_types = self.typeck_results.user_provided_types();
637 let user_ty = user_provided_types.get(cast_ty.hir_id);
640 "cast({:?}) has ty w/ hir_id {:?} and user provided ty {:?}",
641 expr, cast_ty.hir_id, user_ty,
644 // Check to see if this cast is a "coercion cast", where the cast is actually done
645 // using a coercion (or is a no-op).
646 let cast = if self.typeck_results().is_coercion_cast(source.hir_id) {
647 // Convert the lexpr to a vexpr.
648 ExprKind::Use { source: self.mirror_expr(source) }
649 } else if self.typeck_results().expr_ty(source).is_region_ptr() {
650 // Special cased so that we can type check that the element
651 // type of the source matches the pointed to type of the
654 source: self.mirror_expr(source),
655 cast: PointerCast::ArrayToPointer,
658 // check whether this is casting an enum variant discriminant
659 // to prevent cycles, we refer to the discriminant initializer
660 // which is always an integer and thus doesn't need to know the
661 // enum's layout (or its tag type) to compute it during const eval
665 // B = A as isize + 4,
667 // The correct solution would be to add symbolic computations to miri,
668 // so we wouldn't have to compute and store the actual value
669 let var = if let hir::ExprKind::Path(ref qpath) = source.kind {
670 let res = self.typeck_results().qpath_res(qpath, source.hir_id);
671 self.typeck_results().node_type(source.hir_id).ty_adt_def().and_then(
672 |adt_def| match res {
674 DefKind::Ctor(CtorOf::Variant, CtorKind::Const),
677 let idx = adt_def.variant_index_with_ctor_id(variant_ctor_id);
678 let (d, o) = adt_def.discriminant_def_for_variant(idx);
679 use rustc_middle::ty::util::IntTypeExt;
680 let ty = adt_def.repr.discr_type();
681 let ty = ty.to_ty(self.tcx());
691 let source = if let Some((did, offset, var_ty)) = var {
692 let mk_const = |literal| Expr {
696 kind: ExprKind::Literal { literal, user_ty: None, const_id: None },
698 let offset = self.thir.exprs.push(mk_const(ty::Const::from_bits(
701 self.param_env.and(var_ty),
705 // in case we are offsetting from a computed discriminant
706 // and not the beginning of discriminants (which is always `0`)
707 let substs = InternalSubsts::identity_for_item(self.tcx(), did);
708 let lhs = ty::ConstS {
709 val: ty::ConstKind::Unevaluated(ty::Unevaluated::new(
710 ty::WithOptConstParam::unknown(did),
715 let lhs = self.thir.exprs.push(mk_const(self.tcx().mk_const(lhs)));
717 ExprKind::Binary { op: BinOp::Add, lhs: lhs, rhs: offset };
718 self.thir.exprs.push(Expr {
728 self.mirror_expr(source)
731 ExprKind::Cast { source: source }
734 if let Some(user_ty) = user_ty {
735 // NOTE: Creating a new Expr and wrapping a Cast inside of it may be
736 // inefficient, revisit this when performance becomes an issue.
737 let cast_expr = self.thir.exprs.push(Expr {
743 debug!("make_mirror_unadjusted: (cast) user_ty={:?}", user_ty);
745 ExprKind::ValueTypeAscription { source: cast_expr, user_ty: Some(*user_ty) }
750 hir::ExprKind::Type(ref source, ref ty) => {
751 let user_provided_types = self.typeck_results.user_provided_types();
752 let user_ty = user_provided_types.get(ty.hir_id).copied();
753 debug!("make_mirror_unadjusted: (type) user_ty={:?}", user_ty);
754 let mirrored = self.mirror_expr(source);
755 if source.is_syntactic_place_expr() {
756 ExprKind::PlaceTypeAscription { source: mirrored, user_ty }
758 ExprKind::ValueTypeAscription { source: mirrored, user_ty }
761 hir::ExprKind::DropTemps(ref source) => {
762 ExprKind::Use { source: self.mirror_expr(source) }
764 hir::ExprKind::Box(ref value) => ExprKind::Box { value: self.mirror_expr(value) },
765 hir::ExprKind::Array(ref fields) => {
766 ExprKind::Array { fields: self.mirror_exprs(fields) }
768 hir::ExprKind::Tup(ref fields) => ExprKind::Tuple { fields: self.mirror_exprs(fields) },
770 hir::ExprKind::Yield(ref v, _) => ExprKind::Yield { value: self.mirror_expr(v) },
771 hir::ExprKind::Err => unreachable!(),
774 Expr { temp_lifetime, ty: expr_ty, span: expr.span, kind }
777 fn user_substs_applied_to_res(
781 ) -> Option<ty::CanonicalUserType<'tcx>> {
782 debug!("user_substs_applied_to_res: res={:?}", res);
783 let user_provided_type = match res {
784 // A reference to something callable -- e.g., a fn, method, or
785 // a tuple-struct or tuple-variant. This has the type of a
786 // `Fn` but with the user-given substitutions.
787 Res::Def(DefKind::Fn, _)
788 | Res::Def(DefKind::AssocFn, _)
789 | Res::Def(DefKind::Ctor(_, CtorKind::Fn), _)
790 | Res::Def(DefKind::Const, _)
791 | Res::Def(DefKind::AssocConst, _) => {
792 self.typeck_results().user_provided_types().get(hir_id).copied()
795 // A unit struct/variant which is used as a value (e.g.,
796 // `None`). This has the type of the enum/struct that defines
797 // this variant -- but with the substitutions given by the
799 Res::Def(DefKind::Ctor(_, CtorKind::Const), _) => {
800 self.user_substs_applied_to_ty_of_hir_id(hir_id)
803 // `Self` is used in expression as a tuple struct constructor or a unit struct constructor
804 Res::SelfCtor(_) => self.user_substs_applied_to_ty_of_hir_id(hir_id),
806 _ => bug!("user_substs_applied_to_res: unexpected res {:?} at {:?}", res, hir_id),
808 debug!("user_substs_applied_to_res: user_provided_type={:?}", user_provided_type);
814 expr: &hir::Expr<'_>,
816 overloaded_callee: Option<(DefId, SubstsRef<'tcx>)>,
818 let temp_lifetime = self.region_scope_tree.temporary_scope(expr.hir_id.local_id);
819 let (def_id, substs, user_ty) = match overloaded_callee {
820 Some((def_id, substs)) => (def_id, substs, None),
823 self.typeck_results().type_dependent_def(expr.hir_id).unwrap_or_else(|| {
824 span_bug!(expr.span, "no type-dependent def for method callee")
826 let user_ty = self.user_substs_applied_to_res(expr.hir_id, Res::Def(kind, def_id));
827 debug!("method_callee: user_ty={:?}", user_ty);
828 (def_id, self.typeck_results().node_substs(expr.hir_id), user_ty)
831 let ty = self.tcx().mk_fn_def(def_id, substs);
836 kind: ExprKind::Literal {
837 literal: ty::Const::zero_sized(self.tcx(), ty),
844 fn convert_arm(&mut self, arm: &'tcx hir::Arm<'tcx>) -> ArmId {
846 pattern: self.pattern_from_hir(&arm.pat),
847 guard: arm.guard.as_ref().map(|g| match g {
848 hir::Guard::If(ref e) => Guard::If(self.mirror_expr(e)),
849 hir::Guard::IfLet(ref pat, ref e) => {
850 Guard::IfLet(self.pattern_from_hir(pat), self.mirror_expr(e))
853 body: self.mirror_expr(arm.body),
854 lint_level: LintLevel::Explicit(arm.hir_id),
855 scope: region::Scope { id: arm.hir_id.local_id, data: region::ScopeData::Node },
858 self.thir.arms.push(arm)
861 fn convert_path_expr(&mut self, expr: &'tcx hir::Expr<'tcx>, res: Res) -> ExprKind<'tcx> {
862 let substs = self.typeck_results().node_substs(expr.hir_id);
864 // A regular function, constructor function or a constant.
865 Res::Def(DefKind::Fn, _)
866 | Res::Def(DefKind::AssocFn, _)
867 | Res::Def(DefKind::Ctor(_, CtorKind::Fn), _)
868 | Res::SelfCtor(..) => {
869 let user_ty = self.user_substs_applied_to_res(expr.hir_id, res);
870 debug!("convert_path_expr: user_ty={:?}", user_ty);
872 literal: ty::Const::zero_sized(
874 self.typeck_results().node_type(expr.hir_id),
881 Res::Def(DefKind::ConstParam, def_id) => {
882 let hir_id = self.tcx.hir().local_def_id_to_hir_id(def_id.expect_local());
883 let item_id = self.tcx.hir().get_parent_node(hir_id);
884 let item_def_id = self.tcx.hir().local_def_id(item_id);
885 let generics = self.tcx.generics_of(item_def_id);
886 let index = generics.param_def_id_to_index[&def_id];
887 let name = self.tcx.hir().name(hir_id);
888 let val = ty::ConstKind::Param(ty::ParamConst::new(index, name));
890 literal: self.tcx.mk_const(ty::ConstS {
892 ty: self.typeck_results().node_type(expr.hir_id),
895 const_id: Some(def_id),
899 Res::Def(DefKind::Const, def_id) | Res::Def(DefKind::AssocConst, def_id) => {
900 let user_ty = self.user_substs_applied_to_res(expr.hir_id, res);
901 debug!("convert_path_expr: (const) user_ty={:?}", user_ty);
903 literal: self.tcx.mk_const(ty::ConstS {
904 val: ty::ConstKind::Unevaluated(ty::Unevaluated::new(
905 ty::WithOptConstParam::unknown(def_id),
908 ty: self.typeck_results().node_type(expr.hir_id),
911 const_id: Some(def_id),
915 Res::Def(DefKind::Ctor(_, CtorKind::Const), def_id) => {
916 let user_provided_types = self.typeck_results.user_provided_types();
917 let user_provided_type = user_provided_types.get(expr.hir_id).copied();
918 debug!("convert_path_expr: user_provided_type={:?}", user_provided_type);
919 let ty = self.typeck_results().node_type(expr.hir_id);
921 // A unit struct/variant which is used as a value.
922 // We return a completely different ExprKind here to account for this special case.
923 ty::Adt(adt_def, substs) => ExprKind::Adt(Box::new(Adt {
925 variant_index: adt_def.variant_index_with_ctor_id(def_id),
927 user_ty: user_provided_type,
928 fields: Box::new([]),
931 _ => bug!("unexpected ty: {:?}", ty),
935 // We encode uses of statics as a `*&STATIC` where the `&STATIC` part is
936 // a constant reference (or constant raw pointer for `static mut`) in MIR
937 Res::Def(DefKind::Static, id) => {
938 let ty = self.tcx.static_ptr_ty(id);
939 let temp_lifetime = self.region_scope_tree.temporary_scope(expr.hir_id.local_id);
940 let kind = if self.tcx.is_thread_local_static(id) {
941 ExprKind::ThreadLocalRef(id)
943 let alloc_id = self.tcx.create_static_alloc(id);
944 ExprKind::StaticRef { alloc_id, ty, def_id: id }
947 arg: self.thir.exprs.push(Expr { ty, temp_lifetime, span: expr.span, kind }),
951 Res::Local(var_hir_id) => self.convert_var(var_hir_id),
953 _ => span_bug!(expr.span, "res `{:?}` not yet implemented", res),
957 fn convert_var(&mut self, var_hir_id: hir::HirId) -> ExprKind<'tcx> {
958 // We want upvars here not captures.
959 // Captures will be handled in MIR.
962 .upvars_mentioned(self.body_owner)
963 .map_or(false, |upvars| upvars.contains_key(&var_hir_id));
966 "convert_var({:?}): is_upvar={}, body_owner={:?}",
967 var_hir_id, is_upvar, self.body_owner
971 ExprKind::UpvarRef { closure_def_id: self.body_owner, var_hir_id }
973 ExprKind::VarRef { id: var_hir_id }
977 fn overloaded_operator(
979 expr: &'tcx hir::Expr<'tcx>,
981 ) -> ExprKind<'tcx> {
982 let fun = self.method_callee(expr, expr.span, None);
983 let fun = self.thir.exprs.push(fun);
985 ty: self.thir[fun].ty,
988 from_hir_call: false,
995 expr: &'tcx hir::Expr<'tcx>,
997 overloaded_callee: Option<(DefId, SubstsRef<'tcx>)>,
1000 ) -> ExprKind<'tcx> {
1001 // For an overloaded *x or x[y] expression of type T, the method
1002 // call returns an &T and we must add the deref so that the types
1003 // line up (this is because `*x` and `x[y]` represent places):
1005 // Reconstruct the output assuming it's a reference with the
1006 // same region and mutability as the receiver. This holds for
1007 // `Deref(Mut)::Deref(_mut)` and `Index(Mut)::index(_mut)`.
1008 let ty::Ref(region, _, mutbl) = *self.thir[args[0]].ty.kind() else {
1009 span_bug!(span, "overloaded_place: receiver is not a reference");
1011 let ref_ty = self.tcx.mk_ref(region, ty::TypeAndMut { ty: place_ty, mutbl });
1013 // construct the complete expression `foo()` for the overloaded call,
1014 // which will yield the &T type
1015 let temp_lifetime = self.region_scope_tree.temporary_scope(expr.hir_id.local_id);
1016 let fun = self.method_callee(expr, span, overloaded_callee);
1017 let fun = self.thir.exprs.push(fun);
1018 let fun_ty = self.thir[fun].ty;
1019 let ref_expr = self.thir.exprs.push(Expr {
1023 kind: ExprKind::Call { ty: fun_ty, fun, args, from_hir_call: false, fn_span: span },
1026 // construct and return a deref wrapper `*foo()`
1027 ExprKind::Deref { arg: ref_expr }
1030 fn convert_captured_hir_place(
1032 closure_expr: &'tcx hir::Expr<'tcx>,
1033 place: HirPlace<'tcx>,
1035 let temp_lifetime = self.region_scope_tree.temporary_scope(closure_expr.hir_id.local_id);
1036 let var_ty = place.base_ty;
1038 // The result of capture analysis in `rustc_typeck/check/upvar.rs`represents a captured path
1039 // as it's seen for use within the closure and not at the time of closure creation.
1041 // That is we see expect to see it start from a captured upvar and not something that is local
1042 // to the closure's parent.
1043 let var_hir_id = match place.base {
1044 HirPlaceBase::Upvar(upvar_id) => upvar_id.var_path.hir_id,
1045 base => bug!("Expected an upvar, found {:?}", base),
1048 let mut captured_place_expr = Expr {
1051 span: closure_expr.span,
1052 kind: self.convert_var(var_hir_id),
1055 for proj in place.projections.iter() {
1056 let kind = match proj.kind {
1057 HirProjectionKind::Deref => {
1058 ExprKind::Deref { arg: self.thir.exprs.push(captured_place_expr) }
1060 HirProjectionKind::Field(field, ..) => {
1061 // Variant index will always be 0, because for multi-variant
1062 // enums, we capture the enum entirely.
1064 lhs: self.thir.exprs.push(captured_place_expr),
1065 name: Field::new(field as usize),
1068 HirProjectionKind::Index | HirProjectionKind::Subslice => {
1069 // We don't capture these projections, so we can ignore them here
1074 captured_place_expr =
1075 Expr { temp_lifetime, ty: proj.ty, span: closure_expr.span, kind };
1083 closure_expr: &'tcx hir::Expr<'tcx>,
1084 captured_place: &'tcx ty::CapturedPlace<'tcx>,
1087 let upvar_capture = captured_place.info.capture_kind;
1088 let captured_place_expr =
1089 self.convert_captured_hir_place(closure_expr, captured_place.place.clone());
1090 let temp_lifetime = self.region_scope_tree.temporary_scope(closure_expr.hir_id.local_id);
1092 match upvar_capture {
1093 ty::UpvarCapture::ByValue => captured_place_expr,
1094 ty::UpvarCapture::ByRef(upvar_borrow) => {
1095 let borrow_kind = match upvar_borrow {
1096 ty::BorrowKind::ImmBorrow => BorrowKind::Shared,
1097 ty::BorrowKind::UniqueImmBorrow => BorrowKind::Unique,
1098 ty::BorrowKind::MutBorrow => BorrowKind::Mut { allow_two_phase_borrow: false },
1103 span: closure_expr.span,
1104 kind: ExprKind::Borrow {
1106 arg: self.thir.exprs.push(captured_place_expr),
1113 /// Converts a list of named fields (i.e., for struct-like struct/enum ADTs) into FieldExpr.
1114 fn field_refs(&mut self, fields: &'tcx [hir::ExprField<'tcx>]) -> Box<[FieldExpr]> {
1117 .map(|field| FieldExpr {
1118 name: Field::new(self.tcx.field_index(field.hir_id, self.typeck_results)),
1119 expr: self.mirror_expr(field.expr),
1125 trait ToBorrowKind {
1126 fn to_borrow_kind(&self) -> BorrowKind;
1129 impl ToBorrowKind for AutoBorrowMutability {
1130 fn to_borrow_kind(&self) -> BorrowKind {
1131 use rustc_middle::ty::adjustment::AllowTwoPhase;
1133 AutoBorrowMutability::Mut { allow_two_phase_borrow } => BorrowKind::Mut {
1134 allow_two_phase_borrow: match allow_two_phase_borrow {
1135 AllowTwoPhase::Yes => true,
1136 AllowTwoPhase::No => false,
1139 AutoBorrowMutability::Not => BorrowKind::Shared,
1144 impl ToBorrowKind for hir::Mutability {
1145 fn to_borrow_kind(&self) -> BorrowKind {
1147 hir::Mutability::Mut => BorrowKind::Mut { allow_two_phase_borrow: false },
1148 hir::Mutability::Not => BorrowKind::Shared,
1153 fn bin_op(op: hir::BinOpKind) -> BinOp {
1155 hir::BinOpKind::Add => BinOp::Add,
1156 hir::BinOpKind::Sub => BinOp::Sub,
1157 hir::BinOpKind::Mul => BinOp::Mul,
1158 hir::BinOpKind::Div => BinOp::Div,
1159 hir::BinOpKind::Rem => BinOp::Rem,
1160 hir::BinOpKind::BitXor => BinOp::BitXor,
1161 hir::BinOpKind::BitAnd => BinOp::BitAnd,
1162 hir::BinOpKind::BitOr => BinOp::BitOr,
1163 hir::BinOpKind::Shl => BinOp::Shl,
1164 hir::BinOpKind::Shr => BinOp::Shr,
1165 hir::BinOpKind::Eq => BinOp::Eq,
1166 hir::BinOpKind::Lt => BinOp::Lt,
1167 hir::BinOpKind::Le => BinOp::Le,
1168 hir::BinOpKind::Ne => BinOp::Ne,
1169 hir::BinOpKind::Ge => BinOp::Ge,
1170 hir::BinOpKind::Gt => BinOp::Gt,
1171 _ => bug!("no equivalent for ast binop {:?}", op),