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-rw-r--r--compiler/rustc_mir_build/src/thir/cx/expr.rs1117
1 files changed, 1117 insertions, 0 deletions
diff --git a/compiler/rustc_mir_build/src/thir/cx/expr.rs b/compiler/rustc_mir_build/src/thir/cx/expr.rs
new file mode 100644
index 000000000..985601712
--- /dev/null
+++ b/compiler/rustc_mir_build/src/thir/cx/expr.rs
@@ -0,0 +1,1117 @@
+use crate::thir::cx::region::Scope;
+use crate::thir::cx::Cx;
+use crate::thir::util::UserAnnotatedTyHelpers;
+use rustc_data_structures::stack::ensure_sufficient_stack;
+use rustc_hir as hir;
+use rustc_hir::def::{CtorKind, CtorOf, DefKind, Res};
+use rustc_index::vec::Idx;
+use rustc_middle::hir::place::Place as HirPlace;
+use rustc_middle::hir::place::PlaceBase as HirPlaceBase;
+use rustc_middle::hir::place::ProjectionKind as HirProjectionKind;
+use rustc_middle::middle::region;
+use rustc_middle::mir::{self, BinOp, BorrowKind, Field, UnOp};
+use rustc_middle::thir::*;
+use rustc_middle::ty::adjustment::{
+ Adjust, Adjustment, AutoBorrow, AutoBorrowMutability, PointerCast,
+};
+use rustc_middle::ty::subst::{InternalSubsts, SubstsRef};
+use rustc_middle::ty::{
+ self, AdtKind, InlineConstSubsts, InlineConstSubstsParts, ScalarInt, Ty, UpvarSubsts, UserType,
+};
+use rustc_span::def_id::DefId;
+use rustc_span::Span;
+use rustc_target::abi::VariantIdx;
+
+impl<'tcx> Cx<'tcx> {
+ pub(crate) fn mirror_expr(&mut self, expr: &'tcx hir::Expr<'tcx>) -> ExprId {
+ // `mirror_expr` is recursing very deep. Make sure the stack doesn't overflow.
+ ensure_sufficient_stack(|| self.mirror_expr_inner(expr))
+ }
+
+ pub(crate) fn mirror_exprs(&mut self, exprs: &'tcx [hir::Expr<'tcx>]) -> Box<[ExprId]> {
+ exprs.iter().map(|expr| self.mirror_expr_inner(expr)).collect()
+ }
+
+ #[instrument(level = "trace", skip(self, hir_expr))]
+ pub(super) fn mirror_expr_inner(&mut self, hir_expr: &'tcx hir::Expr<'tcx>) -> ExprId {
+ let temp_lifetime =
+ self.rvalue_scopes.temporary_scope(self.region_scope_tree, hir_expr.hir_id.local_id);
+ let expr_scope =
+ region::Scope { id: hir_expr.hir_id.local_id, data: region::ScopeData::Node };
+
+ trace!(?hir_expr.hir_id, ?hir_expr.span);
+
+ let mut expr = self.make_mirror_unadjusted(hir_expr);
+
+ let adjustment_span = match self.adjustment_span {
+ Some((hir_id, span)) if hir_id == hir_expr.hir_id => Some(span),
+ _ => None,
+ };
+
+ // Now apply adjustments, if any.
+ for adjustment in self.typeck_results.expr_adjustments(hir_expr) {
+ trace!(?expr, ?adjustment);
+ let span = expr.span;
+ expr =
+ self.apply_adjustment(hir_expr, expr, adjustment, adjustment_span.unwrap_or(span));
+ }
+
+ // Next, wrap this up in the expr's scope.
+ expr = Expr {
+ temp_lifetime,
+ ty: expr.ty,
+ span: hir_expr.span,
+ kind: ExprKind::Scope {
+ region_scope: expr_scope,
+ value: self.thir.exprs.push(expr),
+ lint_level: LintLevel::Explicit(hir_expr.hir_id),
+ },
+ };
+
+ // Finally, create a destruction scope, if any.
+ if let Some(region_scope) =
+ self.region_scope_tree.opt_destruction_scope(hir_expr.hir_id.local_id)
+ {
+ expr = Expr {
+ temp_lifetime,
+ ty: expr.ty,
+ span: hir_expr.span,
+ kind: ExprKind::Scope {
+ region_scope,
+ value: self.thir.exprs.push(expr),
+ lint_level: LintLevel::Inherited,
+ },
+ };
+ }
+
+ // OK, all done!
+ self.thir.exprs.push(expr)
+ }
+
+ fn apply_adjustment(
+ &mut self,
+ hir_expr: &'tcx hir::Expr<'tcx>,
+ mut expr: Expr<'tcx>,
+ adjustment: &Adjustment<'tcx>,
+ mut span: Span,
+ ) -> Expr<'tcx> {
+ let Expr { temp_lifetime, .. } = expr;
+
+ // Adjust the span from the block, to the last expression of the
+ // block. This is a better span when returning a mutable reference
+ // with too short a lifetime. The error message will use the span
+ // from the assignment to the return place, which should only point
+ // at the returned value, not the entire function body.
+ //
+ // fn return_short_lived<'a>(x: &'a mut i32) -> &'static mut i32 {
+ // x
+ // // ^ error message points at this expression.
+ // }
+ let mut adjust_span = |expr: &mut Expr<'tcx>| {
+ if let ExprKind::Block { body } = &expr.kind {
+ if let Some(last_expr) = body.expr {
+ span = self.thir[last_expr].span;
+ expr.span = span;
+ }
+ }
+ };
+
+ let kind = match adjustment.kind {
+ Adjust::Pointer(PointerCast::Unsize) => {
+ adjust_span(&mut expr);
+ ExprKind::Pointer { cast: PointerCast::Unsize, source: self.thir.exprs.push(expr) }
+ }
+ Adjust::Pointer(cast) => ExprKind::Pointer { cast, source: self.thir.exprs.push(expr) },
+ Adjust::NeverToAny => ExprKind::NeverToAny { source: self.thir.exprs.push(expr) },
+ Adjust::Deref(None) => {
+ adjust_span(&mut expr);
+ ExprKind::Deref { arg: self.thir.exprs.push(expr) }
+ }
+ Adjust::Deref(Some(deref)) => {
+ // We don't need to do call adjust_span here since
+ // deref coercions always start with a built-in deref.
+ let call = deref.method_call(self.tcx(), expr.ty);
+
+ expr = Expr {
+ temp_lifetime,
+ ty: self
+ .tcx
+ .mk_ref(deref.region, ty::TypeAndMut { ty: expr.ty, mutbl: deref.mutbl }),
+ span,
+ kind: ExprKind::Borrow {
+ borrow_kind: deref.mutbl.to_borrow_kind(),
+ arg: self.thir.exprs.push(expr),
+ },
+ };
+
+ let expr = Box::new([self.thir.exprs.push(expr)]);
+
+ self.overloaded_place(hir_expr, adjustment.target, Some(call), expr, deref.span)
+ }
+ Adjust::Borrow(AutoBorrow::Ref(_, m)) => ExprKind::Borrow {
+ borrow_kind: m.to_borrow_kind(),
+ arg: self.thir.exprs.push(expr),
+ },
+ Adjust::Borrow(AutoBorrow::RawPtr(mutability)) => {
+ ExprKind::AddressOf { mutability, arg: self.thir.exprs.push(expr) }
+ }
+ };
+
+ Expr { temp_lifetime, ty: adjustment.target, span, kind }
+ }
+
+ /// Lowers a cast expression.
+ ///
+ /// Dealing with user type annotations is left to the caller.
+ fn mirror_expr_cast(
+ &mut self,
+ source: &'tcx hir::Expr<'tcx>,
+ temp_lifetime: Option<Scope>,
+ span: Span,
+ ) -> ExprKind<'tcx> {
+ let tcx = self.tcx;
+
+ // Check to see if this cast is a "coercion cast", where the cast is actually done
+ // using a coercion (or is a no-op).
+ if self.typeck_results().is_coercion_cast(source.hir_id) {
+ // Convert the lexpr to a vexpr.
+ ExprKind::Use { source: self.mirror_expr(source) }
+ } else if self.typeck_results().expr_ty(source).is_region_ptr() {
+ // Special cased so that we can type check that the element
+ // type of the source matches the pointed to type of the
+ // destination.
+ ExprKind::Pointer {
+ source: self.mirror_expr(source),
+ cast: PointerCast::ArrayToPointer,
+ }
+ } 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 hir::ExprKind::Path(ref qpath) = source.kind else {
+ return ExprKind::Cast { source: self.mirror_expr(source)};
+ };
+
+ let res = self.typeck_results().qpath_res(qpath, source.hir_id);
+ let ty = self.typeck_results().node_type(source.hir_id);
+ let ty::Adt(adt_def, substs) = ty.kind() else {
+ return ExprKind::Cast { source: self.mirror_expr(source)};
+ };
+
+ let Res::Def(DefKind::Ctor(CtorOf::Variant, CtorKind::Const), variant_ctor_id) = res else {
+ return ExprKind::Cast { source: self.mirror_expr(source)};
+ };
+
+ let idx = adt_def.variant_index_with_ctor_id(variant_ctor_id);
+ let (discr_did, discr_offset) = adt_def.discriminant_def_for_variant(idx);
+
+ use rustc_middle::ty::util::IntTypeExt;
+ let ty = adt_def.repr().discr_type();
+ let discr_ty = ty.to_ty(tcx);
+
+ let param_env_ty = self.param_env.and(discr_ty);
+ let size = tcx
+ .layout_of(param_env_ty)
+ .unwrap_or_else(|e| {
+ panic!("could not compute layout for {:?}: {:?}", param_env_ty, e)
+ })
+ .size;
+
+ let lit = ScalarInt::try_from_uint(discr_offset as u128, size).unwrap();
+ let kind = ExprKind::NonHirLiteral { lit, user_ty: None };
+ let offset = self.thir.exprs.push(Expr { temp_lifetime, ty: discr_ty, span, kind });
+
+ let source = match discr_did {
+ // in case we are offsetting from a computed discriminant
+ // and not the beginning of discriminants (which is always `0`)
+ Some(did) => {
+ let kind = ExprKind::NamedConst { def_id: did, substs, user_ty: None };
+ let lhs =
+ self.thir.exprs.push(Expr { temp_lifetime, ty: discr_ty, span, kind });
+ let bin = ExprKind::Binary { op: BinOp::Add, lhs, rhs: offset };
+ self.thir.exprs.push(Expr {
+ temp_lifetime,
+ ty: discr_ty,
+ span: span,
+ kind: bin,
+ })
+ }
+ None => offset,
+ };
+
+ ExprKind::Cast { source }
+ }
+ }
+
+ fn make_mirror_unadjusted(&mut self, expr: &'tcx hir::Expr<'tcx>) -> Expr<'tcx> {
+ let tcx = self.tcx;
+ let expr_ty = self.typeck_results().expr_ty(expr);
+ let expr_span = expr.span;
+ let temp_lifetime =
+ self.rvalue_scopes.temporary_scope(self.region_scope_tree, expr.hir_id.local_id);
+
+ let kind = match expr.kind {
+ // Here comes the interesting stuff:
+ hir::ExprKind::MethodCall(segment, ref args, fn_span) => {
+ // Rewrite a.b(c) into UFCS form like Trait::b(a, c)
+ let expr = self.method_callee(expr, segment.ident.span, None);
+ // When we apply adjustments to the receiver, use the span of
+ // the overall method call for better diagnostics. args[0]
+ // is guaranteed to exist, since a method call always has a receiver.
+ let old_adjustment_span = self.adjustment_span.replace((args[0].hir_id, expr_span));
+ tracing::info!("Using method span: {:?}", expr.span);
+ let args = self.mirror_exprs(args);
+ self.adjustment_span = old_adjustment_span;
+ ExprKind::Call {
+ ty: expr.ty,
+ fun: self.thir.exprs.push(expr),
+ args,
+ from_hir_call: true,
+ fn_span,
+ }
+ }
+
+ hir::ExprKind::Call(ref fun, ref args) => {
+ if self.typeck_results().is_method_call(expr) {
+ // The callee is something implementing Fn, FnMut, or FnOnce.
+ // Find the actual method implementation being called and
+ // build the appropriate UFCS call expression with the
+ // callee-object as expr parameter.
+
+ // rewrite f(u, v) into FnOnce::call_once(f, (u, v))
+
+ let method = self.method_callee(expr, fun.span, None);
+
+ let arg_tys = args.iter().map(|e| self.typeck_results().expr_ty_adjusted(e));
+ let tupled_args = Expr {
+ ty: tcx.mk_tup(arg_tys),
+ temp_lifetime,
+ span: expr.span,
+ kind: ExprKind::Tuple { fields: self.mirror_exprs(args) },
+ };
+ let tupled_args = self.thir.exprs.push(tupled_args);
+
+ ExprKind::Call {
+ ty: method.ty,
+ fun: self.thir.exprs.push(method),
+ args: Box::new([self.mirror_expr(fun), tupled_args]),
+ from_hir_call: true,
+ fn_span: expr.span,
+ }
+ } else {
+ let adt_data =
+ if let hir::ExprKind::Path(hir::QPath::Resolved(_, ref path)) = fun.kind {
+ // Tuple-like ADTs are represented as ExprKind::Call. We convert them here.
+ expr_ty.ty_adt_def().and_then(|adt_def| match path.res {
+ Res::Def(DefKind::Ctor(_, CtorKind::Fn), ctor_id) => {
+ Some((adt_def, adt_def.variant_index_with_ctor_id(ctor_id)))
+ }
+ Res::SelfCtor(..) => Some((adt_def, VariantIdx::new(0))),
+ _ => None,
+ })
+ } else {
+ None
+ };
+ if let Some((adt_def, index)) = adt_data {
+ let substs = self.typeck_results().node_substs(fun.hir_id);
+ let user_provided_types = self.typeck_results().user_provided_types();
+ let user_ty =
+ user_provided_types.get(fun.hir_id).copied().map(|mut u_ty| {
+ if let UserType::TypeOf(ref mut did, _) = &mut u_ty.value {
+ *did = adt_def.did();
+ }
+ u_ty
+ });
+ debug!("make_mirror_unadjusted: (call) user_ty={:?}", user_ty);
+
+ let field_refs = args
+ .iter()
+ .enumerate()
+ .map(|(idx, e)| FieldExpr {
+ name: Field::new(idx),
+ expr: self.mirror_expr(e),
+ })
+ .collect();
+ ExprKind::Adt(Box::new(Adt {
+ adt_def,
+ substs,
+ variant_index: index,
+ fields: field_refs,
+ user_ty,
+ base: None,
+ }))
+ } else {
+ ExprKind::Call {
+ ty: self.typeck_results().node_type(fun.hir_id),
+ fun: self.mirror_expr(fun),
+ args: self.mirror_exprs(args),
+ from_hir_call: true,
+ fn_span: expr.span,
+ }
+ }
+ }
+ }
+
+ hir::ExprKind::AddrOf(hir::BorrowKind::Ref, mutbl, ref arg) => {
+ ExprKind::Borrow { borrow_kind: mutbl.to_borrow_kind(), arg: self.mirror_expr(arg) }
+ }
+
+ hir::ExprKind::AddrOf(hir::BorrowKind::Raw, mutability, ref arg) => {
+ ExprKind::AddressOf { mutability, arg: self.mirror_expr(arg) }
+ }
+
+ hir::ExprKind::Block(ref blk, _) => ExprKind::Block { body: self.mirror_block(blk) },
+
+ hir::ExprKind::Assign(ref lhs, ref rhs, _) => {
+ ExprKind::Assign { lhs: self.mirror_expr(lhs), rhs: self.mirror_expr(rhs) }
+ }
+
+ hir::ExprKind::AssignOp(op, ref lhs, ref rhs) => {
+ if self.typeck_results().is_method_call(expr) {
+ let lhs = self.mirror_expr(lhs);
+ let rhs = self.mirror_expr(rhs);
+ self.overloaded_operator(expr, Box::new([lhs, rhs]))
+ } else {
+ ExprKind::AssignOp {
+ op: bin_op(op.node),
+ lhs: self.mirror_expr(lhs),
+ rhs: self.mirror_expr(rhs),
+ }
+ }
+ }
+
+ hir::ExprKind::Lit(ref lit) => ExprKind::Literal { lit, neg: false },
+
+ hir::ExprKind::Binary(op, ref lhs, ref rhs) => {
+ if self.typeck_results().is_method_call(expr) {
+ let lhs = self.mirror_expr(lhs);
+ let rhs = self.mirror_expr(rhs);
+ self.overloaded_operator(expr, Box::new([lhs, rhs]))
+ } else {
+ // FIXME overflow
+ match op.node {
+ hir::BinOpKind::And => ExprKind::LogicalOp {
+ op: LogicalOp::And,
+ lhs: self.mirror_expr(lhs),
+ rhs: self.mirror_expr(rhs),
+ },
+ hir::BinOpKind::Or => ExprKind::LogicalOp {
+ op: LogicalOp::Or,
+ lhs: self.mirror_expr(lhs),
+ rhs: self.mirror_expr(rhs),
+ },
+ _ => {
+ let op = bin_op(op.node);
+ ExprKind::Binary {
+ op,
+ lhs: self.mirror_expr(lhs),
+ rhs: self.mirror_expr(rhs),
+ }
+ }
+ }
+ }
+ }
+
+ hir::ExprKind::Index(ref lhs, ref index) => {
+ if self.typeck_results().is_method_call(expr) {
+ let lhs = self.mirror_expr(lhs);
+ let index = self.mirror_expr(index);
+ self.overloaded_place(expr, expr_ty, None, Box::new([lhs, index]), expr.span)
+ } else {
+ ExprKind::Index { lhs: self.mirror_expr(lhs), index: self.mirror_expr(index) }
+ }
+ }
+
+ hir::ExprKind::Unary(hir::UnOp::Deref, ref arg) => {
+ if self.typeck_results().is_method_call(expr) {
+ let arg = self.mirror_expr(arg);
+ self.overloaded_place(expr, expr_ty, None, Box::new([arg]), expr.span)
+ } else {
+ ExprKind::Deref { arg: self.mirror_expr(arg) }
+ }
+ }
+
+ hir::ExprKind::Unary(hir::UnOp::Not, ref arg) => {
+ if self.typeck_results().is_method_call(expr) {
+ let arg = self.mirror_expr(arg);
+ self.overloaded_operator(expr, Box::new([arg]))
+ } else {
+ ExprKind::Unary { op: UnOp::Not, arg: self.mirror_expr(arg) }
+ }
+ }
+
+ hir::ExprKind::Unary(hir::UnOp::Neg, ref arg) => {
+ if self.typeck_results().is_method_call(expr) {
+ let arg = self.mirror_expr(arg);
+ self.overloaded_operator(expr, Box::new([arg]))
+ } else if let hir::ExprKind::Lit(ref lit) = arg.kind {
+ ExprKind::Literal { lit, neg: true }
+ } else {
+ ExprKind::Unary { op: UnOp::Neg, arg: self.mirror_expr(arg) }
+ }
+ }
+
+ hir::ExprKind::Struct(ref qpath, ref fields, ref base) => match expr_ty.kind() {
+ ty::Adt(adt, substs) => match adt.adt_kind() {
+ AdtKind::Struct | AdtKind::Union => {
+ let user_provided_types = self.typeck_results().user_provided_types();
+ let user_ty = user_provided_types.get(expr.hir_id).copied();
+ debug!("make_mirror_unadjusted: (struct/union) user_ty={:?}", user_ty);
+ ExprKind::Adt(Box::new(Adt {
+ adt_def: *adt,
+ variant_index: VariantIdx::new(0),
+ substs,
+ user_ty,
+ fields: self.field_refs(fields),
+ base: base.as_ref().map(|base| FruInfo {
+ base: self.mirror_expr(base),
+ field_types: self.typeck_results().fru_field_types()[expr.hir_id]
+ .iter()
+ .copied()
+ .collect(),
+ }),
+ }))
+ }
+ AdtKind::Enum => {
+ let res = self.typeck_results().qpath_res(qpath, expr.hir_id);
+ match res {
+ Res::Def(DefKind::Variant, variant_id) => {
+ assert!(base.is_none());
+
+ let index = adt.variant_index_with_id(variant_id);
+ let user_provided_types =
+ self.typeck_results().user_provided_types();
+ let user_ty = user_provided_types.get(expr.hir_id).copied();
+ debug!("make_mirror_unadjusted: (variant) user_ty={:?}", user_ty);
+ ExprKind::Adt(Box::new(Adt {
+ adt_def: *adt,
+ variant_index: index,
+ substs,
+ user_ty,
+ fields: self.field_refs(fields),
+ base: None,
+ }))
+ }
+ _ => {
+ span_bug!(expr.span, "unexpected res: {:?}", res);
+ }
+ }
+ }
+ },
+ _ => {
+ span_bug!(expr.span, "unexpected type for struct literal: {:?}", expr_ty);
+ }
+ },
+
+ hir::ExprKind::Closure { .. } => {
+ let closure_ty = self.typeck_results().expr_ty(expr);
+ let (def_id, substs, movability) = match *closure_ty.kind() {
+ 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 def_id = def_id.expect_local();
+
+ let upvars = self
+ .typeck_results
+ .closure_min_captures_flattened(def_id)
+ .zip(substs.upvar_tys())
+ .map(|(captured_place, ty)| {
+ let upvars = self.capture_upvar(expr, captured_place, ty);
+ self.thir.exprs.push(upvars)
+ })
+ .collect();
+
+ // Convert the closure fake reads, if any, from hir `Place` to ExprRef
+ let fake_reads = match self.typeck_results.closure_fake_reads.get(&def_id) {
+ Some(fake_reads) => fake_reads
+ .iter()
+ .map(|(place, cause, hir_id)| {
+ let expr = self.convert_captured_hir_place(expr, place.clone());
+ (self.thir.exprs.push(expr), *cause, *hir_id)
+ })
+ .collect(),
+ None => Vec::new(),
+ };
+
+ ExprKind::Closure { closure_id: def_id, substs, upvars, movability, fake_reads }
+ }
+
+ hir::ExprKind::Path(ref qpath) => {
+ let res = self.typeck_results().qpath_res(qpath, expr.hir_id);
+ self.convert_path_expr(expr, res)
+ }
+
+ hir::ExprKind::InlineAsm(ref asm) => ExprKind::InlineAsm {
+ template: asm.template,
+ operands: asm
+ .operands
+ .iter()
+ .map(|(op, _op_sp)| match *op {
+ hir::InlineAsmOperand::In { reg, ref expr } => {
+ InlineAsmOperand::In { reg, expr: self.mirror_expr(expr) }
+ }
+ hir::InlineAsmOperand::Out { reg, late, ref expr } => {
+ InlineAsmOperand::Out {
+ reg,
+ late,
+ expr: expr.as_ref().map(|expr| self.mirror_expr(expr)),
+ }
+ }
+ hir::InlineAsmOperand::InOut { reg, late, ref expr } => {
+ InlineAsmOperand::InOut { reg, late, expr: self.mirror_expr(expr) }
+ }
+ hir::InlineAsmOperand::SplitInOut {
+ reg,
+ late,
+ ref in_expr,
+ ref out_expr,
+ } => InlineAsmOperand::SplitInOut {
+ reg,
+ late,
+ in_expr: self.mirror_expr(in_expr),
+ out_expr: out_expr.as_ref().map(|expr| self.mirror_expr(expr)),
+ },
+ hir::InlineAsmOperand::Const { ref anon_const } => {
+ let anon_const_def_id = tcx.hir().local_def_id(anon_const.hir_id);
+ let value = mir::ConstantKind::from_anon_const(
+ tcx,
+ anon_const_def_id,
+ self.param_env,
+ );
+ let span = tcx.hir().span(anon_const.hir_id);
+
+ InlineAsmOperand::Const { value, span }
+ }
+ hir::InlineAsmOperand::SymFn { ref anon_const } => {
+ let anon_const_def_id = tcx.hir().local_def_id(anon_const.hir_id);
+ let value = mir::ConstantKind::from_anon_const(
+ tcx,
+ anon_const_def_id,
+ self.param_env,
+ );
+ let span = tcx.hir().span(anon_const.hir_id);
+
+ InlineAsmOperand::SymFn { value, span }
+ }
+ hir::InlineAsmOperand::SymStatic { path: _, def_id } => {
+ InlineAsmOperand::SymStatic { def_id }
+ }
+ })
+ .collect(),
+ options: asm.options,
+ line_spans: asm.line_spans,
+ },
+
+ hir::ExprKind::ConstBlock(ref anon_const) => {
+ let ty = self.typeck_results().node_type(anon_const.hir_id);
+ let did = tcx.hir().local_def_id(anon_const.hir_id).to_def_id();
+ let typeck_root_def_id = tcx.typeck_root_def_id(did);
+ let parent_substs =
+ tcx.erase_regions(InternalSubsts::identity_for_item(tcx, typeck_root_def_id));
+ let substs =
+ InlineConstSubsts::new(tcx, InlineConstSubstsParts { parent_substs, ty })
+ .substs;
+
+ ExprKind::ConstBlock { did, substs }
+ }
+ // Now comes the rote stuff:
+ hir::ExprKind::Repeat(ref v, _) => {
+ let ty = self.typeck_results().expr_ty(expr);
+ let ty::Array(_, count) = ty.kind() else {
+ span_bug!(expr.span, "unexpected repeat expr ty: {:?}", ty);
+ };
+
+ ExprKind::Repeat { value: self.mirror_expr(v), count: *count }
+ }
+ hir::ExprKind::Ret(ref v) => {
+ ExprKind::Return { value: v.as_ref().map(|v| self.mirror_expr(v)) }
+ }
+ 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.as_ref().map(|value| self.mirror_expr(value)),
+ },
+ 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::Let(let_expr) => ExprKind::Let {
+ expr: self.mirror_expr(let_expr.init),
+ pat: self.pattern_from_hir(let_expr.pat),
+ },
+ hir::ExprKind::If(cond, then, else_opt) => ExprKind::If {
+ if_then_scope: region::Scope {
+ id: then.hir_id.local_id,
+ data: region::ScopeData::IfThen,
+ },
+ cond: self.mirror_expr(cond),
+ then: self.mirror_expr(then),
+ else_opt: else_opt.map(|el| self.mirror_expr(el)),
+ },
+ hir::ExprKind::Match(ref discr, ref arms, _) => ExprKind::Match {
+ scrutinee: self.mirror_expr(discr),
+ arms: arms.iter().map(|a| self.convert_arm(a)).collect(),
+ },
+ hir::ExprKind::Loop(ref body, ..) => {
+ let block_ty = self.typeck_results().node_type(body.hir_id);
+ let temp_lifetime = self
+ .rvalue_scopes
+ .temporary_scope(self.region_scope_tree, body.hir_id.local_id);
+ let block = self.mirror_block(body);
+ let body = self.thir.exprs.push(Expr {
+ ty: block_ty,
+ temp_lifetime,
+ span: block.span,
+ kind: ExprKind::Block { body: block },
+ });
+ ExprKind::Loop { body }
+ }
+ hir::ExprKind::Field(ref source, ..) => ExprKind::Field {
+ lhs: self.mirror_expr(source),
+ variant_index: VariantIdx::new(0),
+ name: Field::new(tcx.field_index(expr.hir_id, self.typeck_results)),
+ },
+ hir::ExprKind::Cast(ref source, ref cast_ty) => {
+ // Check for a user-given type annotation on this `cast`
+ let user_provided_types = self.typeck_results.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,
+ );
+
+ let cast = self.mirror_expr_cast(*source, temp_lifetime, expr.span);
+
+ 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 = self.thir.exprs.push(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, user_ty: Some(*user_ty) }
+ } else {
+ cast
+ }
+ }
+ hir::ExprKind::Type(ref source, ref ty) => {
+ let user_provided_types = self.typeck_results.user_provided_types();
+ let user_ty = user_provided_types.get(ty.hir_id).copied();
+ debug!("make_mirror_unadjusted: (type) user_ty={:?}", user_ty);
+ let mirrored = self.mirror_expr(source);
+ if source.is_syntactic_place_expr() {
+ ExprKind::PlaceTypeAscription { source: mirrored, user_ty }
+ } else {
+ ExprKind::ValueTypeAscription { source: mirrored, user_ty }
+ }
+ }
+ hir::ExprKind::DropTemps(ref source) => {
+ ExprKind::Use { source: self.mirror_expr(source) }
+ }
+ hir::ExprKind::Box(ref value) => ExprKind::Box { value: self.mirror_expr(value) },
+ hir::ExprKind::Array(ref fields) => {
+ ExprKind::Array { fields: self.mirror_exprs(fields) }
+ }
+ hir::ExprKind::Tup(ref fields) => ExprKind::Tuple { fields: self.mirror_exprs(fields) },
+
+ hir::ExprKind::Yield(ref v, _) => ExprKind::Yield { value: self.mirror_expr(v) },
+ hir::ExprKind::Err => unreachable!(),
+ };
+
+ Expr { temp_lifetime, ty: expr_ty, span: expr.span, kind }
+ }
+
+ fn user_substs_applied_to_res(
+ &mut self,
+ 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::AssocFn, _)
+ | Res::Def(DefKind::Ctor(_, CtorKind::Fn), _)
+ | Res::Def(DefKind::Const, _)
+ | Res::Def(DefKind::AssocConst, _) => {
+ self.typeck_results().user_provided_types().get(hir_id).copied()
+ }
+
+ // 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), _) => {
+ self.user_substs_applied_to_ty_of_hir_id(hir_id)
+ }
+
+ // `Self` is used in expression as a tuple struct constructor or a unit struct constructor
+ Res::SelfCtor(_) => self.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(
+ &mut self,
+ expr: &hir::Expr<'_>,
+ span: Span,
+ overloaded_callee: Option<(DefId, SubstsRef<'tcx>)>,
+ ) -> Expr<'tcx> {
+ let temp_lifetime =
+ self.rvalue_scopes.temporary_scope(self.region_scope_tree, 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) =
+ self.typeck_results().type_dependent_def(expr.hir_id).unwrap_or_else(|| {
+ span_bug!(expr.span, "no type-dependent def for method callee")
+ });
+ let user_ty = self.user_substs_applied_to_res(expr.hir_id, Res::Def(kind, def_id));
+ debug!("method_callee: user_ty={:?}", user_ty);
+ (def_id, self.typeck_results().node_substs(expr.hir_id), user_ty)
+ }
+ };
+ let ty = self.tcx().mk_fn_def(def_id, substs);
+ Expr { temp_lifetime, ty, span, kind: ExprKind::ZstLiteral { user_ty } }
+ }
+
+ fn convert_arm(&mut self, arm: &'tcx hir::Arm<'tcx>) -> ArmId {
+ let arm = Arm {
+ pattern: self.pattern_from_hir(&arm.pat),
+ guard: arm.guard.as_ref().map(|g| match g {
+ hir::Guard::If(ref e) => Guard::If(self.mirror_expr(e)),
+ hir::Guard::IfLet(ref l) => {
+ Guard::IfLet(self.pattern_from_hir(l.pat), self.mirror_expr(l.init))
+ }
+ }),
+ body: self.mirror_expr(arm.body),
+ lint_level: LintLevel::Explicit(arm.hir_id),
+ scope: region::Scope { id: arm.hir_id.local_id, data: region::ScopeData::Node },
+ span: arm.span,
+ };
+ self.thir.arms.push(arm)
+ }
+
+ fn convert_path_expr(&mut self, expr: &'tcx hir::Expr<'tcx>, res: Res) -> ExprKind<'tcx> {
+ let substs = self.typeck_results().node_substs(expr.hir_id);
+ match res {
+ // A regular function, constructor function or a constant.
+ Res::Def(DefKind::Fn, _)
+ | Res::Def(DefKind::AssocFn, _)
+ | Res::Def(DefKind::Ctor(_, CtorKind::Fn), _)
+ | Res::SelfCtor(_) => {
+ let user_ty = self.user_substs_applied_to_res(expr.hir_id, res);
+ ExprKind::ZstLiteral { user_ty }
+ }
+
+ Res::Def(DefKind::ConstParam, def_id) => {
+ let hir_id = self.tcx.hir().local_def_id_to_hir_id(def_id.expect_local());
+ let item_id = self.tcx.hir().get_parent_node(hir_id);
+ let item_def_id = self.tcx.hir().local_def_id(item_id);
+ let generics = self.tcx.generics_of(item_def_id);
+ let index = generics.param_def_id_to_index[&def_id];
+ let name = self.tcx.hir().name(hir_id);
+ let param = ty::ParamConst::new(index, name);
+
+ ExprKind::ConstParam { param, def_id }
+ }
+
+ Res::Def(DefKind::Const, def_id) | Res::Def(DefKind::AssocConst, def_id) => {
+ let user_ty = self.user_substs_applied_to_res(expr.hir_id, res);
+ ExprKind::NamedConst { def_id, substs, user_ty: user_ty }
+ }
+
+ Res::Def(DefKind::Ctor(_, CtorKind::Const), def_id) => {
+ let user_provided_types = self.typeck_results.user_provided_types();
+ let user_provided_type = user_provided_types.get(expr.hir_id).copied();
+ debug!("convert_path_expr: user_provided_type={:?}", user_provided_type);
+ let ty = self.typeck_results().node_type(expr.hir_id);
+ match ty.kind() {
+ // 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(Box::new(Adt {
+ adt_def: *adt_def,
+ variant_index: adt_def.variant_index_with_ctor_id(def_id),
+ substs,
+ user_ty: user_provided_type,
+ fields: Box::new([]),
+ base: None,
+ })),
+ _ => bug!("unexpected ty: {:?}", ty),
+ }
+ }
+
+ // We encode uses of statics as a `*&STATIC` where the `&STATIC` part is
+ // a constant reference (or constant raw pointer for `static mut`) in MIR
+ Res::Def(DefKind::Static(_), id) => {
+ let ty = self.tcx.static_ptr_ty(id);
+ let temp_lifetime = self
+ .rvalue_scopes
+ .temporary_scope(self.region_scope_tree, expr.hir_id.local_id);
+ let kind = if self.tcx.is_thread_local_static(id) {
+ ExprKind::ThreadLocalRef(id)
+ } else {
+ let alloc_id = self.tcx.create_static_alloc(id);
+ ExprKind::StaticRef { alloc_id, ty, def_id: id }
+ };
+ ExprKind::Deref {
+ arg: self.thir.exprs.push(Expr { ty, temp_lifetime, span: expr.span, kind }),
+ }
+ }
+
+ Res::Local(var_hir_id) => self.convert_var(var_hir_id),
+
+ _ => span_bug!(expr.span, "res `{:?}` not yet implemented", res),
+ }
+ }
+
+ fn convert_var(&mut self, var_hir_id: hir::HirId) -> ExprKind<'tcx> {
+ // We want upvars here not captures.
+ // Captures will be handled in MIR.
+ let is_upvar = self
+ .tcx
+ .upvars_mentioned(self.body_owner)
+ .map_or(false, |upvars| upvars.contains_key(&var_hir_id));
+
+ debug!(
+ "convert_var({:?}): is_upvar={}, body_owner={:?}",
+ var_hir_id, is_upvar, self.body_owner
+ );
+
+ if is_upvar {
+ ExprKind::UpvarRef {
+ closure_def_id: self.body_owner,
+ var_hir_id: LocalVarId(var_hir_id),
+ }
+ } else {
+ ExprKind::VarRef { id: LocalVarId(var_hir_id) }
+ }
+ }
+
+ fn overloaded_operator(
+ &mut self,
+ expr: &'tcx hir::Expr<'tcx>,
+ args: Box<[ExprId]>,
+ ) -> ExprKind<'tcx> {
+ let fun = self.method_callee(expr, expr.span, None);
+ let fun = self.thir.exprs.push(fun);
+ ExprKind::Call {
+ ty: self.thir[fun].ty,
+ fun,
+ args,
+ from_hir_call: false,
+ fn_span: expr.span,
+ }
+ }
+
+ fn overloaded_place(
+ &mut self,
+ expr: &'tcx hir::Expr<'tcx>,
+ place_ty: Ty<'tcx>,
+ overloaded_callee: Option<(DefId, SubstsRef<'tcx>)>,
+ args: Box<[ExprId]>,
+ span: Span,
+ ) -> 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):
+
+ // 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 ty::Ref(region, _, mutbl) = *self.thir[args[0]].ty.kind() else {
+ span_bug!(span, "overloaded_place: receiver is not a reference");
+ };
+ let ref_ty = self.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 =
+ self.rvalue_scopes.temporary_scope(self.region_scope_tree, expr.hir_id.local_id);
+ let fun = self.method_callee(expr, span, overloaded_callee);
+ let fun = self.thir.exprs.push(fun);
+ let fun_ty = self.thir[fun].ty;
+ let ref_expr = self.thir.exprs.push(Expr {
+ temp_lifetime,
+ ty: ref_ty,
+ span,
+ kind: ExprKind::Call { ty: fun_ty, fun, args, from_hir_call: false, fn_span: span },
+ });
+
+ // construct and return a deref wrapper `*foo()`
+ ExprKind::Deref { arg: ref_expr }
+ }
+
+ fn convert_captured_hir_place(
+ &mut self,
+ closure_expr: &'tcx hir::Expr<'tcx>,
+ place: HirPlace<'tcx>,
+ ) -> Expr<'tcx> {
+ let temp_lifetime = self
+ .rvalue_scopes
+ .temporary_scope(self.region_scope_tree, closure_expr.hir_id.local_id);
+ let var_ty = place.base_ty;
+
+ // The result of capture analysis in `rustc_typeck/check/upvar.rs`represents a captured path
+ // as it's seen for use within the closure and not at the time of closure creation.
+ //
+ // That is we see expect to see it start from a captured upvar and not something that is local
+ // to the closure's parent.
+ let var_hir_id = match place.base {
+ HirPlaceBase::Upvar(upvar_id) => upvar_id.var_path.hir_id,
+ base => bug!("Expected an upvar, found {:?}", base),
+ };
+
+ let mut captured_place_expr = Expr {
+ temp_lifetime,
+ ty: var_ty,
+ span: closure_expr.span,
+ kind: self.convert_var(var_hir_id),
+ };
+
+ for proj in place.projections.iter() {
+ let kind = match proj.kind {
+ HirProjectionKind::Deref => {
+ ExprKind::Deref { arg: self.thir.exprs.push(captured_place_expr) }
+ }
+ HirProjectionKind::Field(field, variant_index) => ExprKind::Field {
+ lhs: self.thir.exprs.push(captured_place_expr),
+ variant_index,
+ name: Field::new(field as usize),
+ },
+ HirProjectionKind::Index | HirProjectionKind::Subslice => {
+ // We don't capture these projections, so we can ignore them here
+ continue;
+ }
+ };
+
+ captured_place_expr =
+ Expr { temp_lifetime, ty: proj.ty, span: closure_expr.span, kind };
+ }
+
+ captured_place_expr
+ }
+
+ fn capture_upvar(
+ &mut self,
+ closure_expr: &'tcx hir::Expr<'tcx>,
+ captured_place: &'tcx ty::CapturedPlace<'tcx>,
+ upvar_ty: Ty<'tcx>,
+ ) -> Expr<'tcx> {
+ let upvar_capture = captured_place.info.capture_kind;
+ let captured_place_expr =
+ self.convert_captured_hir_place(closure_expr, captured_place.place.clone());
+ let temp_lifetime = self
+ .rvalue_scopes
+ .temporary_scope(self.region_scope_tree, closure_expr.hir_id.local_id);
+
+ match upvar_capture {
+ ty::UpvarCapture::ByValue => captured_place_expr,
+ ty::UpvarCapture::ByRef(upvar_borrow) => {
+ let borrow_kind = match upvar_borrow {
+ 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: self.thir.exprs.push(captured_place_expr),
+ },
+ }
+ }
+ }
+ }
+
+ /// Converts a list of named fields (i.e., for struct-like struct/enum ADTs) into FieldExpr.
+ fn field_refs(&mut self, fields: &'tcx [hir::ExprField<'tcx>]) -> Box<[FieldExpr]> {
+ fields
+ .iter()
+ .map(|field| FieldExpr {
+ name: Field::new(self.tcx.field_index(field.hir_id, self.typeck_results)),
+ expr: self.mirror_expr(field.expr),
+ })
+ .collect()
+ }
+}
+
+trait ToBorrowKind {
+ fn to_borrow_kind(&self) -> BorrowKind;
+}
+
+impl ToBorrowKind for AutoBorrowMutability {
+ fn to_borrow_kind(&self) -> BorrowKind {
+ use rustc_middle::ty::adjustment::AllowTwoPhase;
+ match *self {
+ AutoBorrowMutability::Mut { allow_two_phase_borrow } => BorrowKind::Mut {
+ allow_two_phase_borrow: match allow_two_phase_borrow {
+ AllowTwoPhase::Yes => true,
+ AllowTwoPhase::No => false,
+ },
+ },
+ AutoBorrowMutability::Not => BorrowKind::Shared,
+ }
+ }
+}
+
+impl ToBorrowKind for hir::Mutability {
+ fn to_borrow_kind(&self) -> BorrowKind {
+ match *self {
+ hir::Mutability::Mut => BorrowKind::Mut { allow_two_phase_borrow: false },
+ hir::Mutability::Not => BorrowKind::Shared,
+ }
+ }
+}
+
+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),
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-14 03:14:15 +0000