use rustc_hir as hir;
use rustc_hir::def_id::DefId;
use rustc_hir::lang_items::LangItem;
use rustc_middle::mir::*;
use rustc_middle::query::Providers;
use rustc_middle::ty::GenericArgs;
use rustc_middle::ty::{self, EarlyBinder, GeneratorArgs, Ty, TyCtxt};
use rustc_target::abi::{FieldIdx, VariantIdx, FIRST_VARIANT};
use rustc_index::{Idx, IndexVec};
use rustc_span::Span;
use rustc_target::spec::abi::Abi;
use std::fmt;
use std::iter;
use crate::{
abort_unwinding_calls, add_call_guards, add_moves_for_packed_drops, deref_separator,
pass_manager as pm, remove_noop_landing_pads, simplify,
};
use rustc_middle::mir::patch::MirPatch;
use rustc_mir_dataflow::elaborate_drops::{self, DropElaborator, DropFlagMode, DropStyle};
pub fn provide(providers: &mut Providers) {
providers.mir_shims = make_shim;
}
fn make_shim<'tcx>(tcx: TyCtxt<'tcx>, instance: ty::InstanceDef<'tcx>) -> Body<'tcx> {
debug!("make_shim({:?})", instance);
let mut result = match instance {
ty::InstanceDef::Item(..) => bug!("item {:?} passed to make_shim", instance),
ty::InstanceDef::VTableShim(def_id) => {
let adjustment = Adjustment::Deref { source: DerefSource::MutPtr };
build_call_shim(tcx, instance, Some(adjustment), CallKind::Direct(def_id))
}
ty::InstanceDef::FnPtrShim(def_id, ty) => {
let trait_ = tcx.trait_of_item(def_id).unwrap();
let adjustment = match tcx.fn_trait_kind_from_def_id(trait_) {
Some(ty::ClosureKind::FnOnce) => Adjustment::Identity,
Some(ty::ClosureKind::Fn) => Adjustment::Deref { source: DerefSource::ImmRef },
Some(ty::ClosureKind::FnMut) => Adjustment::Deref { source: DerefSource::MutRef },
None => bug!("fn pointer {:?} is not an fn", ty),
};
build_call_shim(tcx, instance, Some(adjustment), CallKind::Indirect(ty))
}
ty::InstanceDef::ReifyShim(def_id) => {
build_call_shim(tcx, instance, None, CallKind::Direct(def_id))
}
ty::InstanceDef::ClosureOnceShim { call_once: _, track_caller: _ } => {
let fn_mut = tcx.require_lang_item(LangItem::FnMut, None);
let call_mut = tcx
.associated_items(fn_mut)
.in_definition_order()
.find(|it| it.kind == ty::AssocKind::Fn)
.unwrap()
.def_id;
build_call_shim(tcx, instance, Some(Adjustment::RefMut), CallKind::Direct(call_mut))
}
ty::InstanceDef::DropGlue(def_id, ty) => {
if let Some(ty::Generator(gen_def_id, args, _)) = ty.map(Ty::kind) {
let body = tcx.optimized_mir(*gen_def_id).generator_drop().unwrap();
let mut body = EarlyBinder::bind(body.clone()).instantiate(tcx, args);
debug!("make_shim({:?}) = {:?}", instance, body);
pm::run_passes(
tcx,
&mut body,
&[],
Some(MirPhase::Runtime(RuntimePhase::Optimized)),
);
return body;
}
build_drop_shim(tcx, def_id, ty)
}
ty::InstanceDef::ThreadLocalShim(..) => build_thread_local_shim(tcx, instance),
ty::InstanceDef::CloneShim(def_id, ty) => build_clone_shim(tcx, def_id, ty),
ty::InstanceDef::FnPtrAddrShim(def_id, ty) => build_fn_ptr_addr_shim(tcx, def_id, ty),
ty::InstanceDef::Virtual(..) => {
bug!("InstanceDef::Virtual ({:?}) is for direct calls only", instance)
}
ty::InstanceDef::Intrinsic(_) => {
bug!("creating shims from intrinsics ({:?}) is unsupported", instance)
}
};
debug!("make_shim({:?}) = untransformed {:?}", instance, result);
pm::run_passes_no_validate(
tcx,
&mut result,
&[
&add_moves_for_packed_drops::AddMovesForPackedDrops,
&deref_separator::Derefer,
&remove_noop_landing_pads::RemoveNoopLandingPads,
&simplify::SimplifyCfg::MakeShim,
&add_call_guards::CriticalCallEdges,
&abort_unwinding_calls::AbortUnwindingCalls,
],
Some(MirPhase::Runtime(RuntimePhase::Optimized)),
);
debug!("make_shim({:?}) = {:?}", instance, result);
result
}
#[derive(Copy, Clone, Debug, PartialEq)]
enum DerefSource {
ImmRef,
MutRef,
MutPtr,
}
#[derive(Copy, Clone, Debug, PartialEq)]
enum Adjustment {
Identity,
Deref { source: DerefSource },
RefMut,
}
#[derive(Copy, Clone, Debug, PartialEq)]
enum CallKind<'tcx> {
Indirect(Ty<'tcx>),
Direct(DefId),
}
fn local_decls_for_sig<'tcx>(
sig: &ty::FnSig<'tcx>,
span: Span,
) -> IndexVec<Local, LocalDecl<'tcx>> {
iter::once(LocalDecl::new(sig.output(), span))
.chain(sig.inputs().iter().map(|ity| LocalDecl::new(*ity, span).immutable()))
.collect()
}
fn build_drop_shim<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId, ty: Option<Ty<'tcx>>) -> Body<'tcx> {
debug!("build_drop_shim(def_id={:?}, ty={:?})", def_id, ty);
assert!(!matches!(ty, Some(ty) if ty.is_generator()));
let args = if let Some(ty) = ty {
tcx.mk_args(&[ty.into()])
} else {
GenericArgs::identity_for_item(tcx, def_id)
};
let sig = tcx.fn_sig(def_id).instantiate(tcx, args);
let sig = tcx.erase_late_bound_regions(sig);
let span = tcx.def_span(def_id);
let source_info = SourceInfo::outermost(span);
let return_block = BasicBlock::new(1);
let mut blocks = IndexVec::with_capacity(2);
let block = |blocks: &mut IndexVec<_, _>, kind| {
blocks.push(BasicBlockData {
statements: vec![],
terminator: Some(Terminator { source_info, kind }),
is_cleanup: false,
})
};
block(&mut blocks, TerminatorKind::Goto { target: return_block });
block(&mut blocks, TerminatorKind::Return);
let source = MirSource::from_instance(ty::InstanceDef::DropGlue(def_id, ty));
let mut body =
new_body(source, blocks, local_decls_for_sig(&sig, span), sig.inputs().len(), span);
let mut dropee_ptr = Place::from(Local::new(1 + 0));
if tcx.sess.opts.unstable_opts.mir_emit_retag {
let reborrow = Rvalue::Ref(
tcx.lifetimes.re_erased,
BorrowKind::Mut { kind: MutBorrowKind::Default },
tcx.mk_place_deref(dropee_ptr),
);
let ref_ty = reborrow.ty(body.local_decls(), tcx);
dropee_ptr = body.local_decls.push(LocalDecl::new(ref_ty, span)).into();
let new_statements = [
StatementKind::Assign(Box::new((dropee_ptr, reborrow))),
StatementKind::Retag(RetagKind::FnEntry, Box::new(dropee_ptr)),
];
for s in new_statements {
body.basic_blocks_mut()[START_BLOCK]
.statements
.push(Statement { source_info, kind: s });
}
}
if ty.is_some() {
let patch = {
let param_env = tcx.param_env_reveal_all_normalized(def_id);
let mut elaborator =
DropShimElaborator { body: &body, patch: MirPatch::new(&body), tcx, param_env };
let dropee = tcx.mk_place_deref(dropee_ptr);
let resume_block = elaborator.patch.resume_block();
elaborate_drops::elaborate_drop(
&mut elaborator,
source_info,
dropee,
(),
return_block,
elaborate_drops::Unwind::To(resume_block),
START_BLOCK,
);
elaborator.patch
};
patch.apply(&mut body);
}
body
}
fn new_body<'tcx>(
source: MirSource<'tcx>,
basic_blocks: IndexVec<BasicBlock, BasicBlockData<'tcx>>,
local_decls: IndexVec<Local, LocalDecl<'tcx>>,
arg_count: usize,
span: Span,
) -> Body<'tcx> {
Body::new(
source,
basic_blocks,
IndexVec::from_elem_n(
SourceScopeData {
span,
parent_scope: None,
inlined: None,
inlined_parent_scope: None,
local_data: ClearCrossCrate::Clear,
},
1,
),
local_decls,
IndexVec::new(),
arg_count,
vec![],
span,
None,
None,
)
}
pub struct DropShimElaborator<'a, 'tcx> {
pub body: &'a Body<'tcx>,
pub patch: MirPatch<'tcx>,
pub tcx: TyCtxt<'tcx>,
pub param_env: ty::ParamEnv<'tcx>,
}
impl fmt::Debug for DropShimElaborator<'_, '_> {
fn fmt(&self, _f: &mut fmt::Formatter<'_>) -> Result<(), fmt::Error> {
Ok(())
}
}
impl<'a, 'tcx> DropElaborator<'a, 'tcx> for DropShimElaborator<'a, 'tcx> {
type Path = ();
fn patch(&mut self) -> &mut MirPatch<'tcx> {
&mut self.patch
}
fn body(&self) -> &'a Body<'tcx> {
self.body
}
fn tcx(&self) -> TyCtxt<'tcx> {
self.tcx
}
fn param_env(&self) -> ty::ParamEnv<'tcx> {
self.param_env
}
fn drop_style(&self, _path: Self::Path, mode: DropFlagMode) -> DropStyle {
match mode {
DropFlagMode::Shallow => {
DropStyle::Static
}
DropFlagMode::Deep => {
DropStyle::Open
}
}
}
fn get_drop_flag(&mut self, _path: Self::Path) -> Option<Operand<'tcx>> {
None
}
fn clear_drop_flag(&mut self, _location: Location, _path: Self::Path, _mode: DropFlagMode) {}
fn field_subpath(&self, _path: Self::Path, _field: FieldIdx) -> Option<Self::Path> {
None
}
fn deref_subpath(&self, _path: Self::Path) -> Option<Self::Path> {
None
}
fn downcast_subpath(&self, _path: Self::Path, _variant: VariantIdx) -> Option<Self::Path> {
Some(())
}
fn array_subpath(&self, _path: Self::Path, _index: u64, _size: u64) -> Option<Self::Path> {
None
}
}
fn build_thread_local_shim<'tcx>(tcx: TyCtxt<'tcx>, instance: ty::InstanceDef<'tcx>) -> Body<'tcx> {
let def_id = instance.def_id();
let span = tcx.def_span(def_id);
let source_info = SourceInfo::outermost(span);
let mut blocks = IndexVec::with_capacity(1);
blocks.push(BasicBlockData {
statements: vec![Statement {
source_info,
kind: StatementKind::Assign(Box::new((
Place::return_place(),
Rvalue::ThreadLocalRef(def_id),
))),
}],
terminator: Some(Terminator { source_info, kind: TerminatorKind::Return }),
is_cleanup: false,
});
new_body(
MirSource::from_instance(instance),
blocks,
IndexVec::from_raw(vec![LocalDecl::new(tcx.thread_local_ptr_ty(def_id), span)]),
0,
span,
)
}
fn build_clone_shim<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId, self_ty: Ty<'tcx>) -> Body<'tcx> {
debug!("build_clone_shim(def_id={:?})", def_id);
let param_env = tcx.param_env_reveal_all_normalized(def_id);
let mut builder = CloneShimBuilder::new(tcx, def_id, self_ty);
let is_copy = self_ty.is_copy_modulo_regions(tcx, param_env);
let dest = Place::return_place();
let src = tcx.mk_place_deref(Place::from(Local::new(1 + 0)));
match self_ty.kind() {
_ if is_copy => builder.copy_shim(),
ty::Closure(_, args) => builder.tuple_like_shim(dest, src, args.as_closure().upvar_tys()),
ty::Tuple(..) => builder.tuple_like_shim(dest, src, self_ty.tuple_fields()),
ty::Generator(gen_def_id, args, hir::Movability::Movable) => {
builder.generator_shim(dest, src, *gen_def_id, args.as_generator())
}
_ => bug!("clone shim for `{:?}` which is not `Copy` and is not an aggregate", self_ty),
};
builder.into_mir()
}
struct CloneShimBuilder<'tcx> {
tcx: TyCtxt<'tcx>,
def_id: DefId,
local_decls: IndexVec<Local, LocalDecl<'tcx>>,
blocks: IndexVec<BasicBlock, BasicBlockData<'tcx>>,
span: Span,
sig: ty::FnSig<'tcx>,
}
impl<'tcx> CloneShimBuilder<'tcx> {
fn new(tcx: TyCtxt<'tcx>, def_id: DefId, self_ty: Ty<'tcx>) -> Self {
let sig = tcx.fn_sig(def_id).instantiate(tcx, &[self_ty.into()]);
let sig = tcx.erase_late_bound_regions(sig);
let span = tcx.def_span(def_id);
CloneShimBuilder {
tcx,
def_id,
local_decls: local_decls_for_sig(&sig, span),
blocks: IndexVec::new(),
span,
sig,
}
}
fn into_mir(self) -> Body<'tcx> {
let source = MirSource::from_instance(ty::InstanceDef::CloneShim(
self.def_id,
self.sig.inputs_and_output[0],
));
new_body(source, self.blocks, self.local_decls, self.sig.inputs().len(), self.span)
}
fn source_info(&self) -> SourceInfo {
SourceInfo::outermost(self.span)
}
fn block(
&mut self,
statements: Vec<Statement<'tcx>>,
kind: TerminatorKind<'tcx>,
is_cleanup: bool,
) -> BasicBlock {
let source_info = self.source_info();
self.blocks.push(BasicBlockData {
statements,
terminator: Some(Terminator { source_info, kind }),
is_cleanup,
})
}
fn block_index_offset(&self, offset: usize) -> BasicBlock {
BasicBlock::new(self.blocks.len() + offset)
}
fn make_statement(&self, kind: StatementKind<'tcx>) -> Statement<'tcx> {
Statement { source_info: self.source_info(), kind }
}
fn copy_shim(&mut self) {
let rcvr = self.tcx.mk_place_deref(Place::from(Local::new(1 + 0)));
let ret_statement = self.make_statement(StatementKind::Assign(Box::new((
Place::return_place(),
Rvalue::Use(Operand::Copy(rcvr)),
))));
self.block(vec![ret_statement], TerminatorKind::Return, false);
}
fn make_place(&mut self, mutability: Mutability, ty: Ty<'tcx>) -> Place<'tcx> {
let span = self.span;
let mut local = LocalDecl::new(ty, span);
if mutability.is_not() {
local = local.immutable();
}
Place::from(self.local_decls.push(local))
}
fn make_clone_call(
&mut self,
dest: Place<'tcx>,
src: Place<'tcx>,
ty: Ty<'tcx>,
next: BasicBlock,
cleanup: BasicBlock,
) {
let tcx = self.tcx;
let func_ty = Ty::new_fn_def(tcx, self.def_id, [ty]);
let func = Operand::Constant(Box::new(ConstOperand {
span: self.span,
user_ty: None,
const_: Const::zero_sized(func_ty),
}));
let ref_loc = self.make_place(
Mutability::Not,
Ty::new_ref(
tcx,
tcx.lifetimes.re_erased,
ty::TypeAndMut { ty, mutbl: hir::Mutability::Not },
),
);
let statement = self.make_statement(StatementKind::Assign(Box::new((
ref_loc,
Rvalue::Ref(tcx.lifetimes.re_erased, BorrowKind::Shared, src),
))));
self.block(
vec![statement],
TerminatorKind::Call {
func,
args: vec![Operand::Move(ref_loc)],
destination: dest,
target: Some(next),
unwind: UnwindAction::Cleanup(cleanup),
call_source: CallSource::Normal,
fn_span: self.span,
},
false,
);
}
fn clone_fields<I>(
&mut self,
dest: Place<'tcx>,
src: Place<'tcx>,
target: BasicBlock,
mut unwind: BasicBlock,
tys: I,
) -> BasicBlock
where
I: IntoIterator<Item = Ty<'tcx>>,
{
for (i, ity) in tys.into_iter().enumerate() {
let field = FieldIdx::new(i);
let src_field = self.tcx.mk_place_field(src, field, ity);
let dest_field = self.tcx.mk_place_field(dest, field, ity);
let next_unwind = self.block_index_offset(1);
let next_block = self.block_index_offset(2);
self.make_clone_call(dest_field, src_field, ity, next_block, unwind);
self.block(
vec![],
TerminatorKind::Drop {
place: dest_field,
target: unwind,
unwind: UnwindAction::Terminate(UnwindTerminateReason::InCleanup),
replace: false,
},
true,
);
unwind = next_unwind;
}
self.block(vec![], TerminatorKind::Goto { target }, false);
unwind
}
fn tuple_like_shim<I>(&mut self, dest: Place<'tcx>, src: Place<'tcx>, tys: I)
where
I: IntoIterator<Item = Ty<'tcx>>,
{
self.block(vec![], TerminatorKind::Goto { target: self.block_index_offset(3) }, false);
let unwind = self.block(vec![], TerminatorKind::UnwindResume, true);
let target = self.block(vec![], TerminatorKind::Return, false);
let _final_cleanup_block = self.clone_fields(dest, src, target, unwind, tys);
}
fn generator_shim(
&mut self,
dest: Place<'tcx>,
src: Place<'tcx>,
gen_def_id: DefId,
args: GeneratorArgs<'tcx>,
) {
self.block(vec![], TerminatorKind::Goto { target: self.block_index_offset(3) }, false);
let unwind = self.block(vec![], TerminatorKind::UnwindResume, true);
let switch = self.block(vec![], TerminatorKind::Unreachable, false);
let unwind = self.clone_fields(dest, src, switch, unwind, args.upvar_tys());
let target = self.block(vec![], TerminatorKind::Return, false);
let unreachable = self.block(vec![], TerminatorKind::Unreachable, false);
let mut cases = Vec::with_capacity(args.state_tys(gen_def_id, self.tcx).count());
for (index, state_tys) in args.state_tys(gen_def_id, self.tcx).enumerate() {
let variant_index = VariantIdx::new(index);
let dest = self.tcx.mk_place_downcast_unnamed(dest, variant_index);
let src = self.tcx.mk_place_downcast_unnamed(src, variant_index);
let clone_block = self.block_index_offset(1);
let start_block = self.block(
vec![self.make_statement(StatementKind::SetDiscriminant {
place: Box::new(Place::return_place()),
variant_index,
})],
TerminatorKind::Goto { target: clone_block },
false,
);
cases.push((index as u128, start_block));
let _final_cleanup_block = self.clone_fields(dest, src, target, unwind, state_tys);
}
let discr_ty = args.discr_ty(self.tcx);
let temp = self.make_place(Mutability::Mut, discr_ty);
let rvalue = Rvalue::Discriminant(src);
let statement = self.make_statement(StatementKind::Assign(Box::new((temp, rvalue))));
match &mut self.blocks[switch] {
BasicBlockData { statements, terminator: Some(Terminator { kind, .. }), .. } => {
statements.push(statement);
*kind = TerminatorKind::SwitchInt {
discr: Operand::Move(temp),
targets: SwitchTargets::new(cases.into_iter(), unreachable),
};
}
BasicBlockData { terminator: None, .. } => unreachable!(),
}
}
}
#[instrument(level = "debug", skip(tcx), ret)]
fn build_call_shim<'tcx>(
tcx: TyCtxt<'tcx>,
instance: ty::InstanceDef<'tcx>,
rcvr_adjustment: Option<Adjustment>,
call_kind: CallKind<'tcx>,
) -> Body<'tcx> {
let (sig_args, untuple_args) = if let ty::InstanceDef::FnPtrShim(_, ty) = instance {
let sig = tcx.erase_late_bound_regions(ty.fn_sig(tcx));
let untuple_args = sig.inputs();
let arg_tup = Ty::new_tup(tcx, untuple_args);
(Some([ty.into(), arg_tup.into()]), Some(untuple_args))
} else {
(None, None)
};
let def_id = instance.def_id();
let sig = tcx.fn_sig(def_id);
let sig = sig.map_bound(|sig| tcx.erase_late_bound_regions(sig));
assert_eq!(sig_args.is_some(), !instance.has_polymorphic_mir_body());
let mut sig = if let Some(sig_args) = sig_args {
sig.instantiate(tcx, &sig_args)
} else {
sig.instantiate_identity()
};
if let CallKind::Indirect(fnty) = call_kind {
let mut inputs_and_output = sig.inputs_and_output.to_vec();
assert_eq!(inputs_and_output.len(), 3);
let self_arg = &mut inputs_and_output[0];
*self_arg = match rcvr_adjustment.unwrap() {
Adjustment::Identity => fnty,
Adjustment::Deref { source } => match source {
DerefSource::ImmRef => Ty::new_imm_ref(tcx, tcx.lifetimes.re_erased, fnty),
DerefSource::MutRef => Ty::new_mut_ref(tcx, tcx.lifetimes.re_erased, fnty),
DerefSource::MutPtr => Ty::new_mut_ptr(tcx, fnty),
},
Adjustment::RefMut => bug!("`RefMut` is never used with indirect calls: {instance:?}"),
};
sig.inputs_and_output = tcx.mk_type_list(&inputs_and_output);
}
if let ty::InstanceDef::VTableShim(..) = instance {
let mut inputs_and_output = sig.inputs_and_output.to_vec();
let self_arg = &mut inputs_and_output[0];
debug_assert!(tcx.generics_of(def_id).has_self && *self_arg == tcx.types.self_param);
*self_arg = Ty::new_mut_ptr(tcx, *self_arg);
sig.inputs_and_output = tcx.mk_type_list(&inputs_and_output);
}
let span = tcx.def_span(def_id);
debug!(?sig);
let mut local_decls = local_decls_for_sig(&sig, span);
let source_info = SourceInfo::outermost(span);
let rcvr_place = || {
assert!(rcvr_adjustment.is_some());
Place::from(Local::new(1 + 0))
};
let mut statements = vec![];
let rcvr = rcvr_adjustment.map(|rcvr_adjustment| match rcvr_adjustment {
Adjustment::Identity => Operand::Move(rcvr_place()),
Adjustment::Deref { source: _ } => Operand::Move(tcx.mk_place_deref(rcvr_place())),
Adjustment::RefMut => {
let ref_rcvr = local_decls.push(
LocalDecl::new(
Ty::new_ref(
tcx,
tcx.lifetimes.re_erased,
ty::TypeAndMut { ty: sig.inputs()[0], mutbl: hir::Mutability::Mut },
),
span,
)
.immutable(),
);
let borrow_kind = BorrowKind::Mut { kind: MutBorrowKind::Default };
statements.push(Statement {
source_info,
kind: StatementKind::Assign(Box::new((
Place::from(ref_rcvr),
Rvalue::Ref(tcx.lifetimes.re_erased, borrow_kind, rcvr_place()),
))),
});
Operand::Move(Place::from(ref_rcvr))
}
});
let (callee, mut args) = match call_kind {
CallKind::Indirect(_) => (rcvr.unwrap(), vec![]),
CallKind::Direct(def_id) => {
let ty = tcx.type_of(def_id).instantiate_identity();
(
Operand::Constant(Box::new(ConstOperand {
span,
user_ty: None,
const_: Const::zero_sized(ty),
})),
rcvr.into_iter().collect::<Vec<_>>(),
)
}
};
let mut arg_range = 0..sig.inputs().len();
if rcvr_adjustment.is_some() {
arg_range.start += 1;
}
if untuple_args.is_some() {
arg_range.end -= 1;
}
args.extend(arg_range.map(|i| Operand::Move(Place::from(Local::new(1 + i)))));
if let Some(untuple_args) = untuple_args {
let tuple_arg = Local::new(1 + (sig.inputs().len() - 1));
args.extend(untuple_args.iter().enumerate().map(|(i, ity)| {
Operand::Move(tcx.mk_place_field(Place::from(tuple_arg), FieldIdx::new(i), *ity))
}));
}
let n_blocks = if let Some(Adjustment::RefMut) = rcvr_adjustment { 5 } else { 2 };
let mut blocks = IndexVec::with_capacity(n_blocks);
let block = |blocks: &mut IndexVec<_, _>, statements, kind, is_cleanup| {
blocks.push(BasicBlockData {
statements,
terminator: Some(Terminator { source_info, kind }),
is_cleanup,
})
};
block(
&mut blocks,
statements,
TerminatorKind::Call {
func: callee,
args,
destination: Place::return_place(),
target: Some(BasicBlock::new(1)),
unwind: if let Some(Adjustment::RefMut) = rcvr_adjustment {
UnwindAction::Cleanup(BasicBlock::new(3))
} else {
UnwindAction::Continue
},
call_source: CallSource::Misc,
fn_span: span,
},
false,
);
if let Some(Adjustment::RefMut) = rcvr_adjustment {
block(
&mut blocks,
vec![],
TerminatorKind::Drop {
place: rcvr_place(),
target: BasicBlock::new(2),
unwind: UnwindAction::Continue,
replace: false,
},
false,
);
}
block(&mut blocks, vec![], TerminatorKind::Return, false);
if let Some(Adjustment::RefMut) = rcvr_adjustment {
block(
&mut blocks,
vec![],
TerminatorKind::Drop {
place: rcvr_place(),
target: BasicBlock::new(4),
unwind: UnwindAction::Terminate(UnwindTerminateReason::InCleanup),
replace: false,
},
true,
);
block(&mut blocks, vec![], TerminatorKind::UnwindResume, true);
}
let mut body =
new_body(MirSource::from_instance(instance), blocks, local_decls, sig.inputs().len(), span);
if let Abi::RustCall = sig.abi {
body.spread_arg = Some(Local::new(sig.inputs().len()));
}
body
}
pub fn build_adt_ctor(tcx: TyCtxt<'_>, ctor_id: DefId) -> Body<'_> {
debug_assert!(tcx.is_constructor(ctor_id));
let param_env = tcx.param_env_reveal_all_normalized(ctor_id);
let sig = tcx
.fn_sig(ctor_id)
.instantiate_identity()
.no_bound_vars()
.expect("LBR in ADT constructor signature");
let sig = tcx.normalize_erasing_regions(param_env, sig);
let ty::Adt(adt_def, args) = sig.output().kind() else {
bug!("unexpected type for ADT ctor {:?}", sig.output());
};
debug!("build_ctor: ctor_id={:?} sig={:?}", ctor_id, sig);
let span = tcx.def_span(ctor_id);
let local_decls = local_decls_for_sig(&sig, span);
let source_info = SourceInfo::outermost(span);
let variant_index =
if adt_def.is_enum() { adt_def.variant_index_with_ctor_id(ctor_id) } else { FIRST_VARIANT };
debug!("build_ctor: variant_index={:?}", variant_index);
let kind = AggregateKind::Adt(adt_def.did(), variant_index, args, None, None);
let variant = adt_def.variant(variant_index);
let statement = Statement {
kind: StatementKind::Assign(Box::new((
Place::return_place(),
Rvalue::Aggregate(
Box::new(kind),
(0..variant.fields.len())
.map(|idx| Operand::Move(Place::from(Local::new(idx + 1))))
.collect(),
),
))),
source_info,
};
let start_block = BasicBlockData {
statements: vec![statement],
terminator: Some(Terminator { source_info, kind: TerminatorKind::Return }),
is_cleanup: false,
};
let source = MirSource::item(ctor_id);
let body = new_body(
source,
IndexVec::from_elem_n(start_block, 1),
local_decls,
sig.inputs().len(),
span,
);
crate::pass_manager::dump_mir_for_phase_change(tcx, &body);
body
}
fn build_fn_ptr_addr_shim<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId, self_ty: Ty<'tcx>) -> Body<'tcx> {
assert!(matches!(self_ty.kind(), ty::FnPtr(..)), "expected fn ptr, found {self_ty}");
let span = tcx.def_span(def_id);
let Some(sig) = tcx.fn_sig(def_id).instantiate(tcx, &[self_ty.into()]).no_bound_vars() else {
span_bug!(span, "FnPtr::addr with bound vars for `{self_ty}`");
};
let locals = local_decls_for_sig(&sig, span);
let source_info = SourceInfo::outermost(span);
let rvalue = Rvalue::Cast(
CastKind::FnPtrToPtr,
Operand::Move(Place::from(Local::new(1))),
Ty::new_imm_ptr(tcx, tcx.types.unit),
);
let stmt = Statement {
source_info,
kind: StatementKind::Assign(Box::new((Place::return_place(), rvalue))),
};
let statements = vec![stmt];
let start_block = BasicBlockData {
statements,
terminator: Some(Terminator { source_info, kind: TerminatorKind::Return }),
is_cleanup: false,
};
let source = MirSource::from_instance(ty::InstanceDef::FnPtrAddrShim(def_id, self_ty));
new_body(source, IndexVec::from_elem_n(start_block, 1), locals, sig.inputs().len(), span)
}