diff options
Diffstat (limited to 'compiler/rustc_mir_transform/src/shim.rs')
-rw-r--r-- | compiler/rustc_mir_transform/src/shim.rs | 107 |
1 files changed, 91 insertions, 16 deletions
diff --git a/compiler/rustc_mir_transform/src/shim.rs b/compiler/rustc_mir_transform/src/shim.rs index ebe63d6cb..2787fe2ce 100644 --- a/compiler/rustc_mir_transform/src/shim.rs +++ b/compiler/rustc_mir_transform/src/shim.rs @@ -5,7 +5,7 @@ use rustc_middle::mir::*; use rustc_middle::ty::query::Providers; use rustc_middle::ty::InternalSubsts; use rustc_middle::ty::{self, EarlyBinder, GeneratorSubsts, Ty, TyCtxt}; -use rustc_target::abi::VariantIdx; +use rustc_target::abi::{FieldIdx, VariantIdx, FIRST_VARIANT}; use rustc_index::vec::{Idx, IndexVec}; @@ -76,7 +76,9 @@ fn make_shim<'tcx>(tcx: TyCtxt<'tcx>, instance: ty::InstanceDef<'tcx>) -> 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) } @@ -307,7 +309,7 @@ impl<'a, 'tcx> DropElaborator<'a, 'tcx> for DropShimElaborator<'a, 'tcx> { fn clear_drop_flag(&mut self, _location: Location, _path: Self::Path, _mode: DropFlagMode) {} - fn field_subpath(&self, _path: Self::Path, _field: Field) -> Option<Self::Path> { + fn field_subpath(&self, _path: Self::Path, _field: FieldIdx) -> Option<Self::Path> { None } fn deref_subpath(&self, _path: Self::Path) -> Option<Self::Path> { @@ -321,6 +323,34 @@ impl<'a, 'tcx> DropElaborator<'a, 'tcx> for DropShimElaborator<'a, 'tcx> { } } +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, + ) +} + /// Builds a `Clone::clone` shim for `self_ty`. Here, `def_id` is `Clone::clone`. 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); @@ -469,7 +499,7 @@ impl<'tcx> CloneShimBuilder<'tcx> { args: vec![Operand::Move(ref_loc)], destination: dest, target: Some(next), - cleanup: Some(cleanup), + unwind: UnwindAction::Cleanup(cleanup), from_hir_call: true, fn_span: self.span, }, @@ -500,7 +530,7 @@ impl<'tcx> CloneShimBuilder<'tcx> { // created by block 2*i. We store this block in `unwind` so that the next clone block // will unwind to it if cloning fails. - let field = Field::new(i); + 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); @@ -510,7 +540,11 @@ impl<'tcx> CloneShimBuilder<'tcx> { self.make_clone_call(dest_field, src_field, ity, next_block, unwind); self.block( vec![], - TerminatorKind::Drop { place: dest_field, target: unwind, unwind: None }, + TerminatorKind::Drop { + place: dest_field, + target: unwind, + unwind: UnwindAction::Terminate, + }, true, ); unwind = next_unwind; @@ -723,7 +757,7 @@ fn build_call_shim<'tcx>( 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)) + Operand::Move(tcx.mk_place_field(Place::from(tuple_arg), FieldIdx::new(i), *ity)) })); } @@ -746,10 +780,10 @@ fn build_call_shim<'tcx>( args, destination: Place::return_place(), target: Some(BasicBlock::new(1)), - cleanup: if let Some(Adjustment::RefMut) = rcvr_adjustment { - Some(BasicBlock::new(3)) + unwind: if let Some(Adjustment::RefMut) = rcvr_adjustment { + UnwindAction::Cleanup(BasicBlock::new(3)) } else { - None + UnwindAction::Continue }, from_hir_call: true, fn_span: span, @@ -762,7 +796,11 @@ fn build_call_shim<'tcx>( block( &mut blocks, vec![], - TerminatorKind::Drop { place: rcvr_place(), target: BasicBlock::new(2), unwind: None }, + TerminatorKind::Drop { + place: rcvr_place(), + target: BasicBlock::new(2), + unwind: UnwindAction::Continue, + }, false, ); } @@ -773,7 +811,11 @@ fn build_call_shim<'tcx>( block( &mut blocks, vec![], - TerminatorKind::Drop { place: rcvr_place(), target: BasicBlock::new(4), unwind: None }, + TerminatorKind::Drop { + place: rcvr_place(), + target: BasicBlock::new(4), + unwind: UnwindAction::Terminate, + }, true, ); @@ -816,11 +858,8 @@ pub fn build_adt_ctor(tcx: TyCtxt<'_>, ctor_id: DefId) -> Body<'_> { 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) - }; + let variant_index = + if adt_def.is_enum() { adt_def.variant_index_with_ctor_id(ctor_id) } else { FIRST_VARIANT }; // Generate the following MIR: // @@ -864,3 +903,39 @@ pub fn build_adt_ctor(tcx: TyCtxt<'_>, ctor_id: DefId) -> Body<'_> { body } + +/// ```ignore (pseudo-impl) +/// impl FnPtr for fn(u32) { +/// fn addr(self) -> usize { +/// self as usize +/// } +/// } +/// ``` +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).subst(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); + // FIXME: use `expose_addr` once we figure out whether function pointers have meaningful provenance. + let rvalue = Rvalue::Cast( + CastKind::FnPtrToPtr, + Operand::Move(Place::from(Local::new(1))), + tcx.mk_imm_ptr(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) +} |