1 use rustc_middle::mir::interpret::{ConstValue, Scalar};
2 use rustc_middle::mir::tcx::PlaceTy;
3 use rustc_middle::{mir::*, thir::*, ty};
5 use rustc_target::abi::VariantIdx;
7 use crate::build::custom::ParseError;
8 use crate::build::expr::as_constant::as_constant_inner;
10 use super::{parse_by_kind, PResult, ParseCtxt};
12 impl<'tcx, 'body> ParseCtxt<'tcx, 'body> {
13 pub fn parse_statement(&self, expr_id: ExprId) -> PResult<StatementKind<'tcx>> {
14 parse_by_kind!(self, expr_id, _, "statement",
15 @call("mir_retag", args) => {
16 Ok(StatementKind::Retag(RetagKind::Default, Box::new(self.parse_place(args[0])?)))
18 @call("mir_retag_raw", args) => {
19 Ok(StatementKind::Retag(RetagKind::Raw, Box::new(self.parse_place(args[0])?)))
21 @call("mir_set_discriminant", args) => {
22 let place = self.parse_place(args[0])?;
23 let var = self.parse_integer_literal(args[1])? as u32;
24 Ok(StatementKind::SetDiscriminant {
25 place: Box::new(place),
26 variant_index: VariantIdx::from_u32(var),
29 ExprKind::Assign { lhs, rhs } => {
30 let lhs = self.parse_place(*lhs)?;
31 let rhs = self.parse_rvalue(*rhs)?;
32 Ok(StatementKind::Assign(Box::new((lhs, rhs))))
37 pub fn parse_terminator(&self, expr_id: ExprId) -> PResult<TerminatorKind<'tcx>> {
38 parse_by_kind!(self, expr_id, expr, "terminator",
39 @call("mir_return", _args) => {
40 Ok(TerminatorKind::Return)
42 @call("mir_goto", args) => {
43 Ok(TerminatorKind::Goto { target: self.parse_block(args[0])? } )
45 ExprKind::Match { scrutinee, arms } => {
46 let discr = self.parse_operand(*scrutinee)?;
47 self.parse_match(arms, expr.span).map(|t| TerminatorKind::SwitchInt { discr, targets: t })
52 fn parse_match(&self, arms: &[ArmId], span: Span) -> PResult<SwitchTargets> {
53 let Some((otherwise, rest)) = arms.split_last() else {
54 return Err(ParseError {
56 item_description: format!("no arms"),
57 expected: "at least one arm".to_string(),
61 let otherwise = &self.thir[*otherwise];
62 let PatKind::Wild = otherwise.pattern.kind else {
63 return Err(ParseError {
65 item_description: format!("{:?}", otherwise.pattern.kind),
66 expected: "wildcard pattern".to_string(),
69 let otherwise = self.parse_block(otherwise.body)?;
71 let mut values = Vec::new();
72 let mut targets = Vec::new();
74 let arm = &self.thir[*arm];
75 let PatKind::Constant { value } = arm.pattern.kind else {
76 return Err(ParseError {
77 span: arm.pattern.span,
78 item_description: format!("{:?}", arm.pattern.kind),
79 expected: "constant pattern".to_string(),
82 values.push(value.eval_bits(self.tcx, self.param_env, arm.pattern.ty));
83 targets.push(self.parse_block(arm.body)?);
86 Ok(SwitchTargets::new(values.into_iter().zip(targets), otherwise))
89 fn parse_rvalue(&self, expr_id: ExprId) -> PResult<Rvalue<'tcx>> {
90 parse_by_kind!(self, expr_id, _, "rvalue",
91 @call("mir_discriminant", args) => self.parse_place(args[0]).map(Rvalue::Discriminant),
92 ExprKind::Borrow { borrow_kind, arg } => Ok(
93 Rvalue::Ref(self.tcx.lifetimes.re_erased, *borrow_kind, self.parse_place(*arg)?)
95 ExprKind::AddressOf { mutability, arg } => Ok(
96 Rvalue::AddressOf(*mutability, self.parse_place(*arg)?)
98 _ => self.parse_operand(expr_id).map(Rvalue::Use),
102 fn parse_operand(&self, expr_id: ExprId) -> PResult<Operand<'tcx>> {
103 parse_by_kind!(self, expr_id, expr, "operand",
104 @call("mir_move", args) => self.parse_place(args[0]).map(Operand::Move),
105 @call("mir_static", args) => self.parse_static(args[0]),
106 @call("mir_static_mut", args) => self.parse_static(args[0]),
107 ExprKind::Literal { .. }
108 | ExprKind::NamedConst { .. }
109 | ExprKind::NonHirLiteral { .. }
110 | ExprKind::ZstLiteral { .. }
111 | ExprKind::ConstParam { .. }
112 | ExprKind::ConstBlock { .. } => {
113 Ok(Operand::Constant(Box::new(
114 as_constant_inner(expr, |_| None, self.tcx)
117 _ => self.parse_place(expr_id).map(Operand::Copy),
121 fn parse_place(&self, expr_id: ExprId) -> PResult<Place<'tcx>> {
122 self.parse_place_inner(expr_id).map(|(x, _)| x)
125 fn parse_place_inner(&self, expr_id: ExprId) -> PResult<(Place<'tcx>, PlaceTy<'tcx>)> {
126 let (parent, proj) = parse_by_kind!(self, expr_id, expr, "place",
127 @call("mir_field", args) => {
128 let (parent, ty) = self.parse_place_inner(args[0])?;
129 let field = Field::from_u32(self.parse_integer_literal(args[1])? as u32);
130 let field_ty = ty.field_ty(self.tcx, field);
131 let proj = PlaceElem::Field(field, field_ty);
132 let place = parent.project_deeper(&[proj], self.tcx);
133 return Ok((place, PlaceTy::from_ty(field_ty)));
135 @call("mir_variant", args) => {
136 (args[0], PlaceElem::Downcast(
138 VariantIdx::from_u32(self.parse_integer_literal(args[1])? as u32)
141 ExprKind::Deref { arg } => {
142 parse_by_kind!(self, *arg, _, "does not matter",
143 @call("mir_make_place", args) => return self.parse_place_inner(args[0]),
144 _ => (*arg, PlaceElem::Deref),
147 ExprKind::Index { lhs, index } => (*lhs, PlaceElem::Index(self.parse_local(*index)?)),
148 ExprKind::Field { lhs, name: field, .. } => (*lhs, PlaceElem::Field(*field, expr.ty)),
150 let place = self.parse_local(expr_id).map(Place::from)?;
151 return Ok((place, PlaceTy::from_ty(expr.ty)))
154 let (parent, ty) = self.parse_place_inner(parent)?;
155 let place = parent.project_deeper(&[proj], self.tcx);
156 let ty = ty.projection_ty(self.tcx, proj);
160 fn parse_local(&self, expr_id: ExprId) -> PResult<Local> {
161 parse_by_kind!(self, expr_id, _, "local",
162 ExprKind::VarRef { id } => Ok(self.local_map[id]),
166 fn parse_block(&self, expr_id: ExprId) -> PResult<BasicBlock> {
167 parse_by_kind!(self, expr_id, _, "basic block",
168 ExprKind::VarRef { id } => Ok(self.block_map[id]),
172 fn parse_static(&self, expr_id: ExprId) -> PResult<Operand<'tcx>> {
173 let expr_id = parse_by_kind!(self, expr_id, _, "static",
174 ExprKind::Deref { arg } => *arg,
177 parse_by_kind!(self, expr_id, expr, "static",
178 ExprKind::StaticRef { alloc_id, ty, .. } => {
180 ConstValue::Scalar(Scalar::from_pointer((*alloc_id).into(), &self.tcx));
181 let literal = ConstantKind::Val(const_val, *ty);
183 Ok(Operand::Constant(Box::new(Constant {
192 fn parse_integer_literal(&self, expr_id: ExprId) -> PResult<u128> {
193 parse_by_kind!(self, expr_id, expr, "constant",
194 ExprKind::Literal { .. }
195 | ExprKind::NamedConst { .. }
196 | ExprKind::NonHirLiteral { .. }
197 | ExprKind::ConstBlock { .. } => Ok({
198 let value = as_constant_inner(expr, |_| None, self.tcx);
199 value.literal.eval_bits(self.tcx, self.param_env, value.ty())