use rustc_middle::mir::interpret::Scalar;
use rustc_middle::mir::tcx::PlaceTy;
use rustc_middle::ty::cast::mir_cast_kind;
use rustc_middle::{mir::*, thir::*, ty};
use rustc_span::source_map::Spanned;
use rustc_span::Span;
use rustc_target::abi::{FieldIdx, VariantIdx};
use crate::build::custom::ParseError;
use crate::build::expr::as_constant::as_constant_inner;
use super::{parse_by_kind, PResult, ParseCtxt};
impl<'tcx, 'body> ParseCtxt<'tcx, 'body> {
pub fn parse_statement(&self, expr_id: ExprId) -> PResult<StatementKind<'tcx>> {
parse_by_kind!(self, expr_id, _, "statement",
@call(mir_storage_live, args) => {
Ok(StatementKind::StorageLive(self.parse_local(args[0])?))
},
@call(mir_storage_dead, args) => {
Ok(StatementKind::StorageDead(self.parse_local(args[0])?))
},
@call(mir_assume, args) => {
let op = self.parse_operand(args[0])?;
Ok(StatementKind::Intrinsic(Box::new(NonDivergingIntrinsic::Assume(op))))
},
@call(mir_deinit, args) => {
Ok(StatementKind::Deinit(Box::new(self.parse_place(args[0])?)))
},
@call(mir_retag, args) => {
Ok(StatementKind::Retag(RetagKind::Default, Box::new(self.parse_place(args[0])?)))
},
@call(mir_set_discriminant, args) => {
let place = self.parse_place(args[0])?;
let var = self.parse_integer_literal(args[1])? as u32;
Ok(StatementKind::SetDiscriminant {
place: Box::new(place),
variant_index: VariantIdx::from_u32(var),
})
},
ExprKind::Assign { lhs, rhs } => {
let lhs = self.parse_place(*lhs)?;
let rhs = self.parse_rvalue(*rhs)?;
Ok(StatementKind::Assign(Box::new((lhs, rhs))))
},
)
}
pub fn parse_terminator(&self, expr_id: ExprId) -> PResult<TerminatorKind<'tcx>> {
parse_by_kind!(self, expr_id, expr, "terminator",
@call(mir_return, _args) => {
Ok(TerminatorKind::Return)
},
@call(mir_goto, args) => {
Ok(TerminatorKind::Goto { target: self.parse_block(args[0])? } )
},
@call(mir_unreachable, _args) => {
Ok(TerminatorKind::Unreachable)
},
@call(mir_unwind_resume, _args) => {
Ok(TerminatorKind::UnwindResume)
},
@call(mir_unwind_terminate, args) => {
Ok(TerminatorKind::UnwindTerminate(self.parse_unwind_terminate_reason(args[0])?))
},
@call(mir_drop, args) => {
Ok(TerminatorKind::Drop {
place: self.parse_place(args[0])?,
target: self.parse_return_to(args[1])?,
unwind: self.parse_unwind_action(args[2])?,
replace: false,
})
},
@call(mir_call, args) => {
self.parse_call(args)
},
ExprKind::Match { scrutinee, arms, .. } => {
let discr = self.parse_operand(*scrutinee)?;
self.parse_match(arms, expr.span).map(|t| TerminatorKind::SwitchInt { discr, targets: t })
},
)
}
fn parse_unwind_terminate_reason(&self, expr_id: ExprId) -> PResult<UnwindTerminateReason> {
parse_by_kind!(self, expr_id, _, "unwind terminate reason",
@variant(mir_unwind_terminate_reason, Abi) => {
Ok(UnwindTerminateReason::Abi)
},
@variant(mir_unwind_terminate_reason, InCleanup) => {
Ok(UnwindTerminateReason::InCleanup)
},
)
}
fn parse_unwind_action(&self, expr_id: ExprId) -> PResult<UnwindAction> {
parse_by_kind!(self, expr_id, _, "unwind action",
@call(mir_unwind_continue, _args) => {
Ok(UnwindAction::Continue)
},
@call(mir_unwind_unreachable, _args) => {
Ok(UnwindAction::Unreachable)
},
@call(mir_unwind_terminate, args) => {
Ok(UnwindAction::Terminate(self.parse_unwind_terminate_reason(args[0])?))
},
@call(mir_unwind_cleanup, args) => {
Ok(UnwindAction::Cleanup(self.parse_block(args[0])?))
},
)
}
fn parse_return_to(&self, expr_id: ExprId) -> PResult<BasicBlock> {
parse_by_kind!(self, expr_id, _, "return block",
@call(mir_return_to, args) => {
self.parse_block(args[0])
},
)
}
fn parse_match(&self, arms: &[ArmId], span: Span) -> PResult<SwitchTargets> {
let Some((otherwise, rest)) = arms.split_last() else {
return Err(ParseError {
span,
item_description: "no arms".to_string(),
expected: "at least one arm".to_string(),
});
};
let otherwise = &self.thir[*otherwise];
let PatKind::Wild = otherwise.pattern.kind else {
return Err(ParseError {
span: otherwise.span,
item_description: format!("{:?}", otherwise.pattern.kind),
expected: "wildcard pattern".to_string(),
});
};
let otherwise = self.parse_block(otherwise.body)?;
let mut values = Vec::new();
let mut targets = Vec::new();
for arm in rest {
let arm = &self.thir[*arm];
let PatKind::Constant { value } = arm.pattern.kind else {
return Err(ParseError {
span: arm.pattern.span,
item_description: format!("{:?}", arm.pattern.kind),
expected: "constant pattern".to_string(),
});
};
values.push(value.eval_bits(self.tcx, self.param_env));
targets.push(self.parse_block(arm.body)?);
}
Ok(SwitchTargets::new(values.into_iter().zip(targets), otherwise))
}
fn parse_call(&self, args: &[ExprId]) -> PResult<TerminatorKind<'tcx>> {
let (destination, call) = parse_by_kind!(self, args[0], _, "function call",
ExprKind::Assign { lhs, rhs } => (*lhs, *rhs),
);
let destination = self.parse_place(destination)?;
let target = self.parse_return_to(args[1])?;
let unwind = self.parse_unwind_action(args[2])?;
parse_by_kind!(self, call, _, "function call",
ExprKind::Call { fun, args, from_hir_call, fn_span, .. } => {
let fun = self.parse_operand(*fun)?;
let args = args
.iter()
.map(|arg|
Ok(Spanned { node: self.parse_operand(*arg)?, span: self.thir.exprs[*arg].span } )
)
.collect::<PResult<Vec<_>>>()?;
Ok(TerminatorKind::Call {
func: fun,
args,
destination,
target: Some(target),
unwind,
call_source: if *from_hir_call { CallSource::Normal } else {
CallSource::OverloadedOperator
},
fn_span: *fn_span,
})
},
)
}
fn parse_rvalue(&self, expr_id: ExprId) -> PResult<Rvalue<'tcx>> {
parse_by_kind!(self, expr_id, expr, "rvalue",
@call(mir_discriminant, args) => self.parse_place(args[0]).map(Rvalue::Discriminant),
@call(mir_cast_transmute, args) => {
let source = self.parse_operand(args[0])?;
Ok(Rvalue::Cast(CastKind::Transmute, source, expr.ty))
},
@call(mir_checked, args) => {
parse_by_kind!(self, args[0], _, "binary op",
ExprKind::Binary { op, lhs, rhs } => Ok(Rvalue::CheckedBinaryOp(
*op, Box::new((self.parse_operand(*lhs)?, self.parse_operand(*rhs)?))
)),
)
},
@call(mir_offset, args) => {
let ptr = self.parse_operand(args[0])?;
let offset = self.parse_operand(args[1])?;
Ok(Rvalue::BinaryOp(BinOp::Offset, Box::new((ptr, offset))))
},
@call(mir_len, args) => Ok(Rvalue::Len(self.parse_place(args[0])?)),
@call(mir_copy_for_deref, args) => Ok(Rvalue::CopyForDeref(self.parse_place(args[0])?)),
ExprKind::Borrow { borrow_kind, arg } => Ok(
Rvalue::Ref(self.tcx.lifetimes.re_erased, *borrow_kind, self.parse_place(*arg)?)
),
ExprKind::AddressOf { mutability, arg } => Ok(
Rvalue::AddressOf(*mutability, self.parse_place(*arg)?)
),
ExprKind::Binary { op, lhs, rhs } => Ok(
Rvalue::BinaryOp(*op, Box::new((self.parse_operand(*lhs)?, self.parse_operand(*rhs)?)))
),
ExprKind::Unary { op, arg } => Ok(
Rvalue::UnaryOp(*op, self.parse_operand(*arg)?)
),
ExprKind::Repeat { value, count } => Ok(
Rvalue::Repeat(self.parse_operand(*value)?, *count)
),
ExprKind::Cast { source } => {
let source = self.parse_operand(*source)?;
let source_ty = source.ty(self.body.local_decls(), self.tcx);
let cast_kind = mir_cast_kind(source_ty, expr.ty);
Ok(Rvalue::Cast(cast_kind, source, expr.ty))
},
ExprKind::Tuple { fields } => Ok(
Rvalue::Aggregate(
Box::new(AggregateKind::Tuple),
fields.iter().map(|e| self.parse_operand(*e)).collect::<Result<_, _>>()?
)
),
ExprKind::Array { fields } => {
let elem_ty = expr.ty.builtin_index().expect("ty must be an array");
Ok(Rvalue::Aggregate(
Box::new(AggregateKind::Array(elem_ty)),
fields.iter().map(|e| self.parse_operand(*e)).collect::<Result<_, _>>()?
))
},
ExprKind::Adt(box AdtExpr{ adt_def, variant_index, args, fields, .. }) => {
let is_union = adt_def.is_union();
let active_field_index = is_union.then(|| fields[0].name);
Ok(Rvalue::Aggregate(
Box::new(AggregateKind::Adt(adt_def.did(), *variant_index, args, None, active_field_index)),
fields.iter().map(|f| self.parse_operand(f.expr)).collect::<Result<_, _>>()?
))
},
_ => self.parse_operand(expr_id).map(Rvalue::Use),
)
}
pub fn parse_operand(&self, expr_id: ExprId) -> PResult<Operand<'tcx>> {
parse_by_kind!(self, expr_id, expr, "operand",
@call(mir_move, args) => self.parse_place(args[0]).map(Operand::Move),
@call(mir_static, args) => self.parse_static(args[0]),
@call(mir_static_mut, args) => self.parse_static(args[0]),
ExprKind::Literal { .. }
| ExprKind::NamedConst { .. }
| ExprKind::NonHirLiteral { .. }
| ExprKind::ZstLiteral { .. }
| ExprKind::ConstParam { .. }
| ExprKind::ConstBlock { .. } => {
Ok(Operand::Constant(Box::new(
as_constant_inner(expr, |_| None, self.tcx)
)))
},
_ => self.parse_place(expr_id).map(Operand::Copy),
)
}
fn parse_place(&self, expr_id: ExprId) -> PResult<Place<'tcx>> {
self.parse_place_inner(expr_id).map(|(x, _)| x)
}
fn parse_place_inner(&self, expr_id: ExprId) -> PResult<(Place<'tcx>, PlaceTy<'tcx>)> {
let (parent, proj) = parse_by_kind!(self, expr_id, expr, "place",
@call(mir_field, args) => {
let (parent, ty) = self.parse_place_inner(args[0])?;
let field = FieldIdx::from_u32(self.parse_integer_literal(args[1])? as u32);
let field_ty = ty.field_ty(self.tcx, field);
let proj = PlaceElem::Field(field, field_ty);
let place = parent.project_deeper(&[proj], self.tcx);
return Ok((place, PlaceTy::from_ty(field_ty)));
},
@call(mir_variant, args) => {
(args[0], PlaceElem::Downcast(
None,
VariantIdx::from_u32(self.parse_integer_literal(args[1])? as u32)
))
},
ExprKind::Deref { arg } => {
parse_by_kind!(self, *arg, _, "does not matter",
@call(mir_make_place, args) => return self.parse_place_inner(args[0]),
_ => (*arg, PlaceElem::Deref),
)
},
ExprKind::Index { lhs, index } => (*lhs, PlaceElem::Index(self.parse_local(*index)?)),
ExprKind::Field { lhs, name: field, .. } => (*lhs, PlaceElem::Field(*field, expr.ty)),
_ => {
let place = self.parse_local(expr_id).map(Place::from)?;
return Ok((place, PlaceTy::from_ty(expr.ty)))
},
);
let (parent, ty) = self.parse_place_inner(parent)?;
let place = parent.project_deeper(&[proj], self.tcx);
let ty = ty.projection_ty(self.tcx, proj);
Ok((place, ty))
}
fn parse_local(&self, expr_id: ExprId) -> PResult<Local> {
parse_by_kind!(self, expr_id, _, "local",
ExprKind::VarRef { id } => Ok(self.local_map[id]),
)
}
fn parse_block(&self, expr_id: ExprId) -> PResult<BasicBlock> {
parse_by_kind!(self, expr_id, _, "basic block",
ExprKind::VarRef { id } => Ok(self.block_map[id]),
)
}
fn parse_static(&self, expr_id: ExprId) -> PResult<Operand<'tcx>> {
let expr_id = parse_by_kind!(self, expr_id, _, "static",
ExprKind::Deref { arg } => *arg,
);
parse_by_kind!(self, expr_id, expr, "static",
ExprKind::StaticRef { alloc_id, ty, .. } => {
let const_val =
ConstValue::Scalar(Scalar::from_pointer((*alloc_id).into(), &self.tcx));
let const_ = Const::Val(const_val, *ty);
Ok(Operand::Constant(Box::new(ConstOperand {
span: expr.span,
user_ty: None,
const_
})))
},
)
}
fn parse_integer_literal(&self, expr_id: ExprId) -> PResult<u128> {
parse_by_kind!(self, expr_id, expr, "constant",
ExprKind::Literal { .. }
| ExprKind::NamedConst { .. }
| ExprKind::NonHirLiteral { .. }
| ExprKind::ConstBlock { .. } => Ok({
let value = as_constant_inner(expr, |_| None, self.tcx);
value.const_.eval_bits(self.tcx, self.param_env)
}),
)
}
}