791 lines
27 KiB
Rust
791 lines
27 KiB
Rust
use rustc_hir as hir;
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use rustc_hir::def_id::DefId;
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use rustc_hir::lang_items::LangItem;
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use rustc_middle::mir::*;
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use rustc_middle::ty::query::Providers;
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use rustc_middle::ty::subst::{InternalSubsts, Subst};
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use rustc_middle::ty::{self, EarlyBinder, Ty, TyCtxt};
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use rustc_target::abi::VariantIdx;
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use rustc_index::vec::{Idx, IndexVec};
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use rustc_span::Span;
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use rustc_target::spec::abi::Abi;
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use std::fmt;
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use std::iter;
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use crate::util::expand_aggregate;
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use crate::{
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abort_unwinding_calls, add_call_guards, add_moves_for_packed_drops, marker, pass_manager as pm,
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remove_noop_landing_pads, simplify,
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};
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use rustc_middle::mir::patch::MirPatch;
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use rustc_mir_dataflow::elaborate_drops::{self, DropElaborator, DropFlagMode, DropStyle};
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pub fn provide(providers: &mut Providers) {
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providers.mir_shims = make_shim;
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}
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fn make_shim<'tcx>(tcx: TyCtxt<'tcx>, instance: ty::InstanceDef<'tcx>) -> Body<'tcx> {
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debug!("make_shim({:?})", instance);
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let mut result = match instance {
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ty::InstanceDef::Item(..) => bug!("item {:?} passed to make_shim", instance),
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ty::InstanceDef::VTableShim(def_id) => {
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build_call_shim(tcx, instance, Some(Adjustment::Deref), CallKind::Direct(def_id))
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}
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ty::InstanceDef::FnPtrShim(def_id, ty) => {
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let trait_ = tcx.trait_of_item(def_id).unwrap();
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let adjustment = match tcx.fn_trait_kind_from_lang_item(trait_) {
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Some(ty::ClosureKind::FnOnce) => Adjustment::Identity,
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Some(ty::ClosureKind::FnMut | ty::ClosureKind::Fn) => Adjustment::Deref,
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None => bug!("fn pointer {:?} is not an fn", ty),
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};
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build_call_shim(tcx, instance, Some(adjustment), CallKind::Indirect(ty))
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}
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// We are generating a call back to our def-id, which the
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// codegen backend knows to turn to an actual call, be it
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// a virtual call, or a direct call to a function for which
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// indirect calls must be codegen'd differently than direct ones
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// (such as `#[track_caller]`).
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ty::InstanceDef::ReifyShim(def_id) => {
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build_call_shim(tcx, instance, None, CallKind::Direct(def_id))
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}
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ty::InstanceDef::ClosureOnceShim { call_once: _, track_caller: _ } => {
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let fn_mut = tcx.require_lang_item(LangItem::FnMut, None);
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let call_mut = tcx
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.associated_items(fn_mut)
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.in_definition_order()
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.find(|it| it.kind == ty::AssocKind::Fn)
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.unwrap()
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.def_id;
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build_call_shim(tcx, instance, Some(Adjustment::RefMut), CallKind::Direct(call_mut))
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}
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ty::InstanceDef::DropGlue(def_id, ty) => {
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// FIXME(#91576): Drop shims for generators aren't subject to the MIR passes at the end
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// of this function. Is this intentional?
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if let Some(ty::Generator(gen_def_id, substs, _)) = ty.map(Ty::kind) {
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let body = tcx.optimized_mir(*gen_def_id).generator_drop().unwrap();
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let body = EarlyBinder(body.clone()).subst(tcx, substs);
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debug!("make_shim({:?}) = {:?}", instance, body);
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return body;
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}
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build_drop_shim(tcx, def_id, ty)
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}
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ty::InstanceDef::CloneShim(def_id, ty) => build_clone_shim(tcx, def_id, ty),
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ty::InstanceDef::Virtual(..) => {
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bug!("InstanceDef::Virtual ({:?}) is for direct calls only", instance)
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}
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ty::InstanceDef::Intrinsic(_) => {
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bug!("creating shims from intrinsics ({:?}) is unsupported", instance)
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}
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};
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debug!("make_shim({:?}) = untransformed {:?}", instance, result);
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pm::run_passes(
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tcx,
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&mut result,
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&[
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&add_moves_for_packed_drops::AddMovesForPackedDrops,
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&remove_noop_landing_pads::RemoveNoopLandingPads,
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&simplify::SimplifyCfg::new("make_shim"),
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&add_call_guards::CriticalCallEdges,
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&abort_unwinding_calls::AbortUnwindingCalls,
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&marker::PhaseChange(MirPhase::Const),
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],
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);
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debug!("make_shim({:?}) = {:?}", instance, result);
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result
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}
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#[derive(Copy, Clone, Debug, PartialEq)]
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enum Adjustment {
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/// Pass the receiver as-is.
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Identity,
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/// We get passed `&[mut] self` and call the target with `*self`.
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///
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/// This either copies `self` (if `Self: Copy`, eg. for function items), or moves out of it
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/// (for `VTableShim`, which effectively is passed `&own Self`).
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Deref,
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/// We get passed `self: Self` and call the target with `&mut self`.
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///
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/// In this case we need to ensure that the `Self` is dropped after the call, as the callee
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/// won't do it for us.
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RefMut,
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}
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#[derive(Copy, Clone, Debug, PartialEq)]
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enum CallKind<'tcx> {
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/// Call the `FnPtr` that was passed as the receiver.
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Indirect(Ty<'tcx>),
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/// Call a known `FnDef`.
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Direct(DefId),
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}
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fn local_decls_for_sig<'tcx>(
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sig: &ty::FnSig<'tcx>,
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span: Span,
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) -> IndexVec<Local, LocalDecl<'tcx>> {
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iter::once(LocalDecl::new(sig.output(), span))
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.chain(sig.inputs().iter().map(|ity| LocalDecl::new(*ity, span).immutable()))
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.collect()
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}
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fn build_drop_shim<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId, ty: Option<Ty<'tcx>>) -> Body<'tcx> {
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debug!("build_drop_shim(def_id={:?}, ty={:?})", def_id, ty);
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assert!(!matches!(ty, Some(ty) if ty.is_generator()));
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let substs = if let Some(ty) = ty {
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tcx.intern_substs(&[ty.into()])
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} else {
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InternalSubsts::identity_for_item(tcx, def_id)
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};
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let sig = tcx.bound_fn_sig(def_id).subst(tcx, substs);
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let sig = tcx.erase_late_bound_regions(sig);
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let span = tcx.def_span(def_id);
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let source_info = SourceInfo::outermost(span);
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let return_block = BasicBlock::new(1);
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let mut blocks = IndexVec::with_capacity(2);
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let block = |blocks: &mut IndexVec<_, _>, kind| {
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blocks.push(BasicBlockData {
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statements: vec![],
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terminator: Some(Terminator { source_info, kind }),
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is_cleanup: false,
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})
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};
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block(&mut blocks, TerminatorKind::Goto { target: return_block });
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block(&mut blocks, TerminatorKind::Return);
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let source = MirSource::from_instance(ty::InstanceDef::DropGlue(def_id, ty));
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let mut body =
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new_body(source, blocks, local_decls_for_sig(&sig, span), sig.inputs().len(), span);
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if ty.is_some() {
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// The first argument (index 0), but add 1 for the return value.
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let dropee_ptr = Place::from(Local::new(1 + 0));
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if tcx.sess.opts.unstable_opts.mir_emit_retag {
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// Function arguments should be retagged, and we make this one raw.
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body.basic_blocks_mut()[START_BLOCK].statements.insert(
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0,
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Statement {
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source_info,
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kind: StatementKind::Retag(RetagKind::Raw, Box::new(dropee_ptr)),
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},
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);
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}
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let patch = {
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let param_env = tcx.param_env_reveal_all_normalized(def_id);
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let mut elaborator =
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DropShimElaborator { body: &body, patch: MirPatch::new(&body), tcx, param_env };
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let dropee = tcx.mk_place_deref(dropee_ptr);
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let resume_block = elaborator.patch.resume_block();
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elaborate_drops::elaborate_drop(
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&mut elaborator,
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source_info,
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dropee,
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(),
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return_block,
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elaborate_drops::Unwind::To(resume_block),
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START_BLOCK,
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);
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elaborator.patch
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};
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patch.apply(&mut body);
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}
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body
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}
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fn new_body<'tcx>(
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source: MirSource<'tcx>,
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basic_blocks: IndexVec<BasicBlock, BasicBlockData<'tcx>>,
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local_decls: IndexVec<Local, LocalDecl<'tcx>>,
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arg_count: usize,
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span: Span,
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) -> Body<'tcx> {
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Body::new(
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source,
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basic_blocks,
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IndexVec::from_elem_n(
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SourceScopeData {
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span,
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parent_scope: None,
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inlined: None,
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inlined_parent_scope: None,
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local_data: ClearCrossCrate::Clear,
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},
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1,
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),
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local_decls,
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IndexVec::new(),
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arg_count,
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vec![],
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span,
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None,
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// FIXME(compiler-errors): is this correct?
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None,
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)
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}
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pub struct DropShimElaborator<'a, 'tcx> {
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pub body: &'a Body<'tcx>,
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pub patch: MirPatch<'tcx>,
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pub tcx: TyCtxt<'tcx>,
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pub param_env: ty::ParamEnv<'tcx>,
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}
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impl fmt::Debug for DropShimElaborator<'_, '_> {
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fn fmt(&self, _f: &mut fmt::Formatter<'_>) -> Result<(), fmt::Error> {
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Ok(())
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}
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}
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impl<'a, 'tcx> DropElaborator<'a, 'tcx> for DropShimElaborator<'a, 'tcx> {
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type Path = ();
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fn patch(&mut self) -> &mut MirPatch<'tcx> {
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&mut self.patch
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}
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fn body(&self) -> &'a Body<'tcx> {
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self.body
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}
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fn tcx(&self) -> TyCtxt<'tcx> {
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self.tcx
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}
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fn param_env(&self) -> ty::ParamEnv<'tcx> {
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self.param_env
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}
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fn drop_style(&self, _path: Self::Path, mode: DropFlagMode) -> DropStyle {
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match mode {
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DropFlagMode::Shallow => {
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// Drops for the contained fields are "shallow" and "static" - they will simply call
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// the field's own drop glue.
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DropStyle::Static
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}
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DropFlagMode::Deep => {
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// The top-level drop is "deep" and "open" - it will be elaborated to a drop ladder
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// dropping each field contained in the value.
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DropStyle::Open
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}
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}
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}
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fn get_drop_flag(&mut self, _path: Self::Path) -> Option<Operand<'tcx>> {
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None
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}
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fn clear_drop_flag(&mut self, _location: Location, _path: Self::Path, _mode: DropFlagMode) {}
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fn field_subpath(&self, _path: Self::Path, _field: Field) -> Option<Self::Path> {
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None
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}
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fn deref_subpath(&self, _path: Self::Path) -> Option<Self::Path> {
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None
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}
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fn downcast_subpath(&self, _path: Self::Path, _variant: VariantIdx) -> Option<Self::Path> {
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Some(())
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}
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fn array_subpath(&self, _path: Self::Path, _index: u64, _size: u64) -> Option<Self::Path> {
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None
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}
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}
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/// Builds a `Clone::clone` shim for `self_ty`. Here, `def_id` is `Clone::clone`.
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fn build_clone_shim<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId, self_ty: Ty<'tcx>) -> Body<'tcx> {
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debug!("build_clone_shim(def_id={:?})", def_id);
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let param_env = tcx.param_env(def_id);
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let mut builder = CloneShimBuilder::new(tcx, def_id, self_ty);
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let is_copy = self_ty.is_copy_modulo_regions(tcx.at(builder.span), param_env);
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let dest = Place::return_place();
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let src = tcx.mk_place_deref(Place::from(Local::new(1 + 0)));
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match self_ty.kind() {
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_ if is_copy => builder.copy_shim(),
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ty::Closure(_, substs) => {
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builder.tuple_like_shim(dest, src, substs.as_closure().upvar_tys())
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}
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ty::Tuple(..) => builder.tuple_like_shim(dest, src, self_ty.tuple_fields()),
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_ => bug!("clone shim for `{:?}` which is not `Copy` and is not an aggregate", self_ty),
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};
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builder.into_mir()
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}
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struct CloneShimBuilder<'tcx> {
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tcx: TyCtxt<'tcx>,
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def_id: DefId,
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local_decls: IndexVec<Local, LocalDecl<'tcx>>,
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blocks: IndexVec<BasicBlock, BasicBlockData<'tcx>>,
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span: Span,
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sig: ty::FnSig<'tcx>,
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}
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impl<'tcx> CloneShimBuilder<'tcx> {
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fn new(tcx: TyCtxt<'tcx>, def_id: DefId, self_ty: Ty<'tcx>) -> Self {
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// we must subst the self_ty because it's
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// otherwise going to be TySelf and we can't index
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// or access fields of a Place of type TySelf.
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let substs = tcx.mk_substs_trait(self_ty, &[]);
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let sig = tcx.bound_fn_sig(def_id).subst(tcx, substs);
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let sig = tcx.erase_late_bound_regions(sig);
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let span = tcx.def_span(def_id);
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CloneShimBuilder {
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tcx,
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def_id,
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local_decls: local_decls_for_sig(&sig, span),
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blocks: IndexVec::new(),
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span,
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sig,
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}
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}
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fn into_mir(self) -> Body<'tcx> {
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let source = MirSource::from_instance(ty::InstanceDef::CloneShim(
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self.def_id,
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self.sig.inputs_and_output[0],
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));
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new_body(source, self.blocks, self.local_decls, self.sig.inputs().len(), self.span)
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}
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fn source_info(&self) -> SourceInfo {
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SourceInfo::outermost(self.span)
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}
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fn block(
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&mut self,
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statements: Vec<Statement<'tcx>>,
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kind: TerminatorKind<'tcx>,
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is_cleanup: bool,
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) -> BasicBlock {
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let source_info = self.source_info();
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self.blocks.push(BasicBlockData {
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statements,
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terminator: Some(Terminator { source_info, kind }),
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is_cleanup,
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})
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}
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/// Gives the index of an upcoming BasicBlock, with an offset.
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/// offset=0 will give you the index of the next BasicBlock,
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/// offset=1 will give the index of the next-to-next block,
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/// offset=-1 will give you the index of the last-created block
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fn block_index_offset(&mut self, offset: usize) -> BasicBlock {
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BasicBlock::new(self.blocks.len() + offset)
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}
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fn make_statement(&self, kind: StatementKind<'tcx>) -> Statement<'tcx> {
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Statement { source_info: self.source_info(), kind }
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}
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fn copy_shim(&mut self) {
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let rcvr = self.tcx.mk_place_deref(Place::from(Local::new(1 + 0)));
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let ret_statement = self.make_statement(StatementKind::Assign(Box::new((
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Place::return_place(),
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Rvalue::Use(Operand::Copy(rcvr)),
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))));
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self.block(vec![ret_statement], TerminatorKind::Return, false);
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}
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fn make_place(&mut self, mutability: Mutability, ty: Ty<'tcx>) -> Place<'tcx> {
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let span = self.span;
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let mut local = LocalDecl::new(ty, span);
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if mutability == Mutability::Not {
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local = local.immutable();
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}
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Place::from(self.local_decls.push(local))
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}
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fn make_clone_call(
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&mut self,
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dest: Place<'tcx>,
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src: Place<'tcx>,
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ty: Ty<'tcx>,
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next: BasicBlock,
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cleanup: BasicBlock,
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) {
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let tcx = self.tcx;
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let substs = tcx.mk_substs_trait(ty, &[]);
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// `func == Clone::clone(&ty) -> ty`
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let func_ty = tcx.mk_fn_def(self.def_id, substs);
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let func = Operand::Constant(Box::new(Constant {
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span: self.span,
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user_ty: None,
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literal: ConstantKind::zero_sized(func_ty),
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}));
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let ref_loc = self.make_place(
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Mutability::Not,
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tcx.mk_ref(tcx.lifetimes.re_erased, ty::TypeAndMut { ty, mutbl: hir::Mutability::Not }),
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);
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// `let ref_loc: &ty = &src;`
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let statement = self.make_statement(StatementKind::Assign(Box::new((
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ref_loc,
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Rvalue::Ref(tcx.lifetimes.re_erased, BorrowKind::Shared, src),
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))));
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// `let loc = Clone::clone(ref_loc);`
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self.block(
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vec![statement],
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TerminatorKind::Call {
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func,
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args: vec![Operand::Move(ref_loc)],
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destination: dest,
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target: Some(next),
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cleanup: Some(cleanup),
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from_hir_call: true,
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fn_span: self.span,
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},
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false,
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);
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}
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fn tuple_like_shim<I>(&mut self, dest: Place<'tcx>, src: Place<'tcx>, tys: I)
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where
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I: IntoIterator<Item = Ty<'tcx>>,
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{
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let mut previous_field = None;
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for (i, ity) in tys.into_iter().enumerate() {
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let field = Field::new(i);
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let src_field = self.tcx.mk_place_field(src, field, ity);
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|
|
let dest_field = self.tcx.mk_place_field(dest, field, ity);
|
|
|
|
// #(2i + 1) is the cleanup block for the previous clone operation
|
|
let cleanup_block = self.block_index_offset(1);
|
|
// #(2i + 2) is the next cloning block
|
|
// (or the Return terminator if this is the last block)
|
|
let next_block = self.block_index_offset(2);
|
|
|
|
// BB #(2i)
|
|
// `dest.i = Clone::clone(&src.i);`
|
|
// Goto #(2i + 2) if ok, #(2i + 1) if unwinding happens.
|
|
self.make_clone_call(dest_field, src_field, ity, next_block, cleanup_block);
|
|
|
|
// BB #(2i + 1) (cleanup)
|
|
if let Some((previous_field, previous_cleanup)) = previous_field.take() {
|
|
// Drop previous field and goto previous cleanup block.
|
|
self.block(
|
|
vec![],
|
|
TerminatorKind::Drop {
|
|
place: previous_field,
|
|
target: previous_cleanup,
|
|
unwind: None,
|
|
},
|
|
true,
|
|
);
|
|
} else {
|
|
// Nothing to drop, just resume.
|
|
self.block(vec![], TerminatorKind::Resume, true);
|
|
}
|
|
|
|
previous_field = Some((dest_field, cleanup_block));
|
|
}
|
|
|
|
self.block(vec![], TerminatorKind::Return, false);
|
|
}
|
|
}
|
|
|
|
/// Builds a "call" shim for `instance`. The shim calls the function specified by `call_kind`,
|
|
/// first adjusting its first argument according to `rcvr_adjustment`.
|
|
fn build_call_shim<'tcx>(
|
|
tcx: TyCtxt<'tcx>,
|
|
instance: ty::InstanceDef<'tcx>,
|
|
rcvr_adjustment: Option<Adjustment>,
|
|
call_kind: CallKind<'tcx>,
|
|
) -> Body<'tcx> {
|
|
debug!(
|
|
"build_call_shim(instance={:?}, rcvr_adjustment={:?}, call_kind={:?})",
|
|
instance, rcvr_adjustment, call_kind
|
|
);
|
|
|
|
// `FnPtrShim` contains the fn pointer type that a call shim is being built for - this is used
|
|
// to substitute into the signature of the shim. It is not necessary for users of this
|
|
// MIR body to perform further substitutions (see `InstanceDef::has_polymorphic_mir_body`).
|
|
let (sig_substs, 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();
|
|
|
|
// Create substitutions for the `Self` and `Args` generic parameters of the shim body.
|
|
let arg_tup = tcx.mk_tup(untuple_args.iter());
|
|
let sig_substs = tcx.mk_substs_trait(ty, &[ty::subst::GenericArg::from(arg_tup)]);
|
|
|
|
(Some(sig_substs), Some(untuple_args))
|
|
} else {
|
|
(None, None)
|
|
};
|
|
|
|
let def_id = instance.def_id();
|
|
let sig = tcx.bound_fn_sig(def_id);
|
|
let sig = sig.map_bound(|sig| tcx.erase_late_bound_regions(sig));
|
|
|
|
assert_eq!(sig_substs.is_some(), !instance.has_polymorphic_mir_body());
|
|
let mut sig =
|
|
if let Some(sig_substs) = sig_substs { sig.subst(tcx, sig_substs) } else { sig.0 };
|
|
|
|
if let CallKind::Indirect(fnty) = call_kind {
|
|
// `sig` determines our local decls, and thus the callee type in the `Call` terminator. This
|
|
// can only be an `FnDef` or `FnPtr`, but currently will be `Self` since the types come from
|
|
// the implemented `FnX` trait.
|
|
|
|
// Apply the opposite adjustment to the MIR input.
|
|
let mut inputs_and_output = sig.inputs_and_output.to_vec();
|
|
|
|
// Initial signature is `fn(&? Self, Args) -> Self::Output` where `Args` is a tuple of the
|
|
// fn arguments. `Self` may be passed via (im)mutable reference or by-value.
|
|
assert_eq!(inputs_and_output.len(), 3);
|
|
|
|
// `Self` is always the original fn type `ty`. The MIR call terminator is only defined for
|
|
// `FnDef` and `FnPtr` callees, not the `Self` type param.
|
|
let self_arg = &mut inputs_and_output[0];
|
|
*self_arg = match rcvr_adjustment.unwrap() {
|
|
Adjustment::Identity => fnty,
|
|
Adjustment::Deref => tcx.mk_imm_ptr(fnty),
|
|
Adjustment::RefMut => tcx.mk_mut_ptr(fnty),
|
|
};
|
|
sig.inputs_and_output = tcx.intern_type_list(&inputs_and_output);
|
|
}
|
|
|
|
// FIXME(eddyb) avoid having this snippet both here and in
|
|
// `Instance::fn_sig` (introduce `InstanceDef::fn_sig`?).
|
|
if let ty::InstanceDef::VTableShim(..) = instance {
|
|
// Modify fn(self, ...) to fn(self: *mut Self, ...)
|
|
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 = tcx.mk_mut_ptr(*self_arg);
|
|
sig.inputs_and_output = tcx.intern_type_list(&inputs_and_output);
|
|
}
|
|
|
|
let span = tcx.def_span(def_id);
|
|
|
|
debug!("build_call_shim: sig={:?}", 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 => Operand::Move(tcx.mk_place_deref(rcvr_place())),
|
|
Adjustment::RefMut => {
|
|
// let rcvr = &mut rcvr;
|
|
let ref_rcvr = local_decls.push(
|
|
LocalDecl::new(
|
|
tcx.mk_ref(
|
|
tcx.lifetimes.re_erased,
|
|
ty::TypeAndMut { ty: sig.inputs()[0], mutbl: hir::Mutability::Mut },
|
|
),
|
|
span,
|
|
)
|
|
.immutable(),
|
|
);
|
|
let borrow_kind = BorrowKind::Mut { allow_two_phase_borrow: false };
|
|
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 {
|
|
// `FnPtr` call has no receiver. Args are untupled below.
|
|
CallKind::Indirect(_) => (rcvr.unwrap(), vec![]),
|
|
|
|
// `FnDef` call with optional receiver.
|
|
CallKind::Direct(def_id) => {
|
|
let ty = tcx.type_of(def_id);
|
|
(
|
|
Operand::Constant(Box::new(Constant {
|
|
span,
|
|
user_ty: None,
|
|
literal: ConstantKind::zero_sized(ty),
|
|
})),
|
|
rcvr.into_iter().collect::<Vec<_>>(),
|
|
)
|
|
}
|
|
};
|
|
|
|
let mut arg_range = 0..sig.inputs().len();
|
|
|
|
// Take the `self` ("receiver") argument out of the range (it's adjusted above).
|
|
if rcvr_adjustment.is_some() {
|
|
arg_range.start += 1;
|
|
}
|
|
|
|
// Take the last argument, if we need to untuple it (handled below).
|
|
if untuple_args.is_some() {
|
|
arg_range.end -= 1;
|
|
}
|
|
|
|
// Pass all of the non-special arguments directly.
|
|
args.extend(arg_range.map(|i| Operand::Move(Place::from(Local::new(1 + i)))));
|
|
|
|
// Untuple the last argument, if we have to.
|
|
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), Field::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,
|
|
})
|
|
};
|
|
|
|
// BB #0
|
|
block(
|
|
&mut blocks,
|
|
statements,
|
|
TerminatorKind::Call {
|
|
func: callee,
|
|
args,
|
|
destination: Place::return_place(),
|
|
target: Some(BasicBlock::new(1)),
|
|
cleanup: if let Some(Adjustment::RefMut) = rcvr_adjustment {
|
|
Some(BasicBlock::new(3))
|
|
} else {
|
|
None
|
|
},
|
|
from_hir_call: true,
|
|
fn_span: span,
|
|
},
|
|
false,
|
|
);
|
|
|
|
if let Some(Adjustment::RefMut) = rcvr_adjustment {
|
|
// BB #1 - drop for Self
|
|
block(
|
|
&mut blocks,
|
|
vec![],
|
|
TerminatorKind::Drop { place: rcvr_place(), target: BasicBlock::new(2), unwind: None },
|
|
false,
|
|
);
|
|
}
|
|
// BB #1/#2 - return
|
|
block(&mut blocks, vec![], TerminatorKind::Return, false);
|
|
if let Some(Adjustment::RefMut) = rcvr_adjustment {
|
|
// BB #3 - drop if closure panics
|
|
block(
|
|
&mut blocks,
|
|
vec![],
|
|
TerminatorKind::Drop { place: rcvr_place(), target: BasicBlock::new(4), unwind: None },
|
|
true,
|
|
);
|
|
|
|
// BB #4 - resume
|
|
block(&mut blocks, vec![], TerminatorKind::Resume, 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(ctor_id);
|
|
|
|
// Normalize the sig.
|
|
let sig = tcx.fn_sig(ctor_id).no_bound_vars().expect("LBR in ADT constructor signature");
|
|
let sig = tcx.normalize_erasing_regions(param_env, sig);
|
|
|
|
let ty::Adt(adt_def, substs) = 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 {
|
|
VariantIdx::new(0)
|
|
};
|
|
|
|
// Generate the following MIR:
|
|
//
|
|
// (return as Variant).field0 = arg0;
|
|
// (return as Variant).field1 = arg1;
|
|
//
|
|
// return;
|
|
debug!("build_ctor: variant_index={:?}", variant_index);
|
|
|
|
let statements = expand_aggregate(
|
|
Place::return_place(),
|
|
adt_def.variant(variant_index).fields.iter().enumerate().map(|(idx, field_def)| {
|
|
(Operand::Move(Place::from(Local::new(idx + 1))), field_def.ty(tcx, substs))
|
|
}),
|
|
AggregateKind::Adt(adt_def.did(), variant_index, substs, None, None),
|
|
source_info,
|
|
tcx,
|
|
)
|
|
.collect();
|
|
|
|
let start_block = BasicBlockData {
|
|
statements,
|
|
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,
|
|
);
|
|
|
|
rustc_middle::mir::dump_mir(tcx, None, "mir_map", &0, &body, |_, _| Ok(()));
|
|
|
|
body
|
|
}
|