diff options
Diffstat (limited to 'compiler/rustc_mir_transform')
29 files changed, 484 insertions, 327 deletions
diff --git a/compiler/rustc_mir_transform/src/add_retag.rs b/compiler/rustc_mir_transform/src/add_retag.rs index 3d22035f0..7d2146214 100644 --- a/compiler/rustc_mir_transform/src/add_retag.rs +++ b/compiler/rustc_mir_transform/src/add_retag.rs @@ -120,7 +120,7 @@ impl<'tcx> MirPass<'tcx> for AddRetag { // PART 3 // Add retag after assignments where data "enters" this function: the RHS is behind a deref and the LHS is not. for block_data in basic_blocks { - // We want to insert statements as we iterate. To this end, we + // We want to insert statements as we iterate. To this end, we // iterate backwards using indices. for i in (0..block_data.statements.len()).rev() { let (retag_kind, place) = match block_data.statements[i].kind { diff --git a/compiler/rustc_mir_transform/src/check_unsafety.rs b/compiler/rustc_mir_transform/src/check_unsafety.rs index e783d1891..adf6ae4c7 100644 --- a/compiler/rustc_mir_transform/src/check_unsafety.rs +++ b/compiler/rustc_mir_transform/src/check_unsafety.rs @@ -1,6 +1,7 @@ use rustc_data_structures::fx::FxHashSet; use rustc_errors::struct_span_err; use rustc_hir as hir; +use rustc_hir::def::DefKind; use rustc_hir::def_id::{DefId, LocalDefId}; use rustc_hir::hir_id::HirId; use rustc_hir::intravisit; @@ -134,6 +135,28 @@ impl<'tcx> Visitor<'tcx> for UnsafetyChecker<'_, 'tcx> { self.super_rvalue(rvalue, location); } + fn visit_operand(&mut self, op: &Operand<'tcx>, location: Location) { + if let Operand::Constant(constant) = op { + let maybe_uneval = match constant.literal { + ConstantKind::Val(..) | ConstantKind::Ty(_) => None, + ConstantKind::Unevaluated(uv, _) => Some(uv), + }; + + if let Some(uv) = maybe_uneval { + if uv.promoted.is_none() { + let def_id = uv.def.def_id_for_type_of(); + if self.tcx.def_kind(def_id) == DefKind::InlineConst { + let local_def_id = def_id.expect_local(); + let UnsafetyCheckResult { violations, used_unsafe_blocks, .. } = + self.tcx.unsafety_check_result(local_def_id); + self.register_violations(violations, used_unsafe_blocks.iter().copied()); + } + } + } + } + self.super_operand(op, location); + } + fn visit_place(&mut self, place: &Place<'tcx>, context: PlaceContext, _location: Location) { // On types with `scalar_valid_range`, prevent // * `&mut x.field` @@ -410,6 +433,12 @@ impl<'tcx> intravisit::Visitor<'tcx> for UnusedUnsafeVisitor<'_, 'tcx> { intravisit::walk_block(self, block); } + fn visit_anon_const(&mut self, c: &'tcx hir::AnonConst) { + if matches!(self.tcx.def_kind(c.def_id), DefKind::InlineConst) { + self.visit_body(self.tcx.hir().body(c.body)) + } + } + fn visit_fn( &mut self, fk: intravisit::FnKind<'tcx>, @@ -461,17 +490,17 @@ fn check_unused_unsafe( unused_unsafes } -fn unsafety_check_result<'tcx>( - tcx: TyCtxt<'tcx>, +fn unsafety_check_result( + tcx: TyCtxt<'_>, def: ty::WithOptConstParam<LocalDefId>, -) -> &'tcx UnsafetyCheckResult { +) -> &UnsafetyCheckResult { debug!("unsafety_violations({:?})", def); // N.B., this borrow is valid because all the consumers of // `mir_built` force this. let body = &tcx.mir_built(def).borrow(); - if body.should_skip() { + if body.is_custom_mir() { return tcx.arena.alloc(UnsafetyCheckResult { violations: Vec::new(), used_unsafe_blocks: FxHashSet::default(), @@ -484,7 +513,7 @@ fn unsafety_check_result<'tcx>( let mut checker = UnsafetyChecker::new(body, def.did, tcx, param_env); checker.visit_body(&body); - let unused_unsafes = (!tcx.is_closure(def.did.to_def_id())) + let unused_unsafes = (!tcx.is_typeck_child(def.did.to_def_id())) .then(|| check_unused_unsafe(tcx, def.did, &checker.used_unsafe_blocks)); tcx.arena.alloc(UnsafetyCheckResult { @@ -516,8 +545,8 @@ fn report_unused_unsafe(tcx: TyCtxt<'_>, kind: UnusedUnsafe, id: HirId) { pub fn check_unsafety(tcx: TyCtxt<'_>, def_id: LocalDefId) { debug!("check_unsafety({:?})", def_id); - // closures are handled by their parent fn. - if tcx.is_closure(def_id.to_def_id()) { + // closures and inline consts are handled by their parent fn. + if tcx.is_typeck_child(def_id.to_def_id()) { return; } diff --git a/compiler/rustc_mir_transform/src/cleanup_post_borrowck.rs b/compiler/rustc_mir_transform/src/cleanup_post_borrowck.rs index 3378923c2..d435d3ee6 100644 --- a/compiler/rustc_mir_transform/src/cleanup_post_borrowck.rs +++ b/compiler/rustc_mir_transform/src/cleanup_post_borrowck.rs @@ -1,39 +1,44 @@ -//! This module provides a pass to replacing the following statements with -//! [`Nop`]s +//! This module provides a pass that removes parts of MIR that are no longer relevant after +//! analysis phase and borrowck. In particular, it removes false edges, user type annotations and +//! replaces following statements with [`Nop`]s: //! //! - [`AscribeUserType`] //! - [`FakeRead`] //! - [`Assign`] statements with a [`Shallow`] borrow //! -//! The `CleanFakeReadsAndBorrows` "pass" is actually implemented as two -//! traversals (aka visits) of the input MIR. The first traversal, -//! `DeleteAndRecordFakeReads`, deletes the fake reads and finds the -//! temporaries read by [`ForMatchGuard`] reads, and `DeleteFakeBorrows` -//! deletes the initialization of those temporaries. -//! //! [`AscribeUserType`]: rustc_middle::mir::StatementKind::AscribeUserType -//! [`Shallow`]: rustc_middle::mir::BorrowKind::Shallow -//! [`FakeRead`]: rustc_middle::mir::StatementKind::FakeRead //! [`Assign`]: rustc_middle::mir::StatementKind::Assign -//! [`ForMatchGuard`]: rustc_middle::mir::FakeReadCause::ForMatchGuard +//! [`FakeRead`]: rustc_middle::mir::StatementKind::FakeRead //! [`Nop`]: rustc_middle::mir::StatementKind::Nop +//! [`Shallow`]: rustc_middle::mir::BorrowKind::Shallow use crate::MirPass; -use rustc_middle::mir::visit::MutVisitor; -use rustc_middle::mir::{Body, BorrowKind, Location, Rvalue}; -use rustc_middle::mir::{Statement, StatementKind}; +use rustc_middle::mir::{Body, BorrowKind, Rvalue, StatementKind, TerminatorKind}; use rustc_middle::ty::TyCtxt; -pub struct CleanupNonCodegenStatements; +pub struct CleanupPostBorrowck; -pub struct DeleteNonCodegenStatements<'tcx> { - tcx: TyCtxt<'tcx>, -} +impl<'tcx> MirPass<'tcx> for CleanupPostBorrowck { + fn run_pass(&self, _tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { + for basic_block in body.basic_blocks.as_mut() { + for statement in basic_block.statements.iter_mut() { + match statement.kind { + StatementKind::AscribeUserType(..) + | StatementKind::Assign(box (_, Rvalue::Ref(_, BorrowKind::Shallow, _))) + | StatementKind::FakeRead(..) => statement.make_nop(), + _ => (), + } + } + let terminator = basic_block.terminator_mut(); + match terminator.kind { + TerminatorKind::FalseEdge { real_target, .. } + | TerminatorKind::FalseUnwind { real_target, .. } => { + terminator.kind = TerminatorKind::Goto { target: real_target }; + } + _ => {} + } + } -impl<'tcx> MirPass<'tcx> for CleanupNonCodegenStatements { - fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { - let mut delete = DeleteNonCodegenStatements { tcx }; - delete.visit_body_preserves_cfg(body); body.user_type_annotations.raw.clear(); for decl in &mut body.local_decls { @@ -41,19 +46,3 @@ impl<'tcx> MirPass<'tcx> for CleanupNonCodegenStatements { } } } - -impl<'tcx> MutVisitor<'tcx> for DeleteNonCodegenStatements<'tcx> { - fn tcx(&self) -> TyCtxt<'tcx> { - self.tcx - } - - fn visit_statement(&mut self, statement: &mut Statement<'tcx>, location: Location) { - match statement.kind { - StatementKind::AscribeUserType(..) - | StatementKind::Assign(box (_, Rvalue::Ref(_, BorrowKind::Shallow, _))) - | StatementKind::FakeRead(..) => statement.make_nop(), - _ => (), - } - self.super_statement(statement, location); - } -} diff --git a/compiler/rustc_mir_transform/src/const_goto.rs b/compiler/rustc_mir_transform/src/const_goto.rs index 0a305a402..40eefda4f 100644 --- a/compiler/rustc_mir_transform/src/const_goto.rs +++ b/compiler/rustc_mir_transform/src/const_goto.rs @@ -82,8 +82,9 @@ impl<'tcx> Visitor<'tcx> for ConstGotoOptimizationFinder<'_, 'tcx> { } let target_bb_terminator = target_bb.terminator(); - let (discr, switch_ty, targets) = target_bb_terminator.kind.as_switch()?; + let (discr, targets) = target_bb_terminator.kind.as_switch()?; if discr.place() == Some(*place) { + let switch_ty = place.ty(self.body.local_decls(), self.tcx).ty; // We now know that the Switch matches on the const place, and it is statementless // Now find which value in the Switch matches the const value. let const_value = diff --git a/compiler/rustc_mir_transform/src/const_prop.rs b/compiler/rustc_mir_transform/src/const_prop.rs index b0514e033..5c45abc5a 100644 --- a/compiler/rustc_mir_transform/src/const_prop.rs +++ b/compiler/rustc_mir_transform/src/const_prop.rs @@ -6,6 +6,7 @@ use std::cell::Cell; use either::Right; use rustc_ast::Mutability; +use rustc_const_eval::const_eval::CheckAlignment; use rustc_data_structures::fx::FxHashSet; use rustc_hir::def::DefKind; use rustc_index::bit_set::BitSet; @@ -22,7 +23,7 @@ use rustc_middle::ty::layout::{LayoutError, LayoutOf, LayoutOfHelpers, TyAndLayo use rustc_middle::ty::InternalSubsts; use rustc_middle::ty::{self, ConstKind, Instance, ParamEnv, Ty, TyCtxt, TypeVisitable}; use rustc_span::{def_id::DefId, Span}; -use rustc_target::abi::{self, HasDataLayout, Size, TargetDataLayout}; +use rustc_target::abi::{self, Align, HasDataLayout, Size, TargetDataLayout}; use rustc_target::spec::abi::Abi as CallAbi; use rustc_trait_selection::traits; @@ -186,16 +187,27 @@ impl<'mir, 'tcx> interpret::Machine<'mir, 'tcx> for ConstPropMachine<'mir, 'tcx> type MemoryKind = !; #[inline(always)] - fn enforce_alignment(_ecx: &InterpCx<'mir, 'tcx, Self>) -> bool { + fn enforce_alignment(_ecx: &InterpCx<'mir, 'tcx, Self>) -> CheckAlignment { // We do not check for alignment to avoid having to carry an `Align` // in `ConstValue::ByRef`. - false + CheckAlignment::No } #[inline(always)] fn enforce_validity(_ecx: &InterpCx<'mir, 'tcx, Self>) -> bool { false // for now, we don't enforce validity } + fn alignment_check_failed( + ecx: &InterpCx<'mir, 'tcx, Self>, + _has: Align, + _required: Align, + _check: CheckAlignment, + ) -> InterpResult<'tcx, ()> { + span_bug!( + ecx.cur_span(), + "`alignment_check_failed` called when no alignment check requested" + ) + } fn load_mir( _ecx: &InterpCx<'mir, 'tcx, Self>, @@ -643,11 +655,7 @@ impl<'mir, 'tcx> ConstPropagator<'mir, 'tcx> { return None; } - if self.tcx.sess.mir_opt_level() >= 4 { - self.eval_rvalue_with_identities(rvalue, place) - } else { - self.use_ecx(|this| this.ecx.eval_rvalue_into_place(rvalue, place)) - } + self.eval_rvalue_with_identities(rvalue, place) } // Attempt to use algebraic identities to eliminate constant expressions @@ -689,8 +697,8 @@ impl<'mir, 'tcx> ConstPropagator<'mir, 'tcx> { BinOp::Mul if const_arg.layout.ty.is_integral() && arg_value == 0 => { if let Rvalue::CheckedBinaryOp(_, _) = rvalue { let val = Immediate::ScalarPair( - const_arg.to_scalar().into(), - Scalar::from_bool(false).into(), + const_arg.to_scalar(), + Scalar::from_bool(false), ); this.ecx.write_immediate(val, &dest) } else { diff --git a/compiler/rustc_mir_transform/src/coverage/graph.rs b/compiler/rustc_mir_transform/src/coverage/graph.rs index 782129be0..78d28f1eb 100644 --- a/compiler/rustc_mir_transform/src/coverage/graph.rs +++ b/compiler/rustc_mir_transform/src/coverage/graph.rs @@ -282,9 +282,9 @@ impl graph::WithPredecessors for CoverageGraph { rustc_index::newtype_index! { /// A node in the control-flow graph of CoverageGraph. + #[debug_format = "bcb{}"] pub(super) struct BasicCoverageBlock { - DEBUG_FORMAT = "bcb{}", - const START_BCB = 0, + const START_BCB = 0; } } diff --git a/compiler/rustc_mir_transform/src/coverage/mod.rs b/compiler/rustc_mir_transform/src/coverage/mod.rs index 604810144..1468afc64 100644 --- a/compiler/rustc_mir_transform/src/coverage/mod.rs +++ b/compiler/rustc_mir_transform/src/coverage/mod.rs @@ -533,10 +533,10 @@ fn make_code_region( } } -fn fn_sig_and_body<'tcx>( - tcx: TyCtxt<'tcx>, +fn fn_sig_and_body( + tcx: TyCtxt<'_>, def_id: DefId, -) -> (Option<&'tcx rustc_hir::FnSig<'tcx>>, &'tcx rustc_hir::Body<'tcx>) { +) -> (Option<&rustc_hir::FnSig<'_>>, &rustc_hir::Body<'_>) { // FIXME(#79625): Consider improving MIR to provide the information needed, to avoid going back // to HIR for it. let hir_node = tcx.hir().get_if_local(def_id).expect("expected DefId is local"); diff --git a/compiler/rustc_mir_transform/src/coverage/query.rs b/compiler/rustc_mir_transform/src/coverage/query.rs index dc1e68b25..3bd7f31b4 100644 --- a/compiler/rustc_mir_transform/src/coverage/query.rs +++ b/compiler/rustc_mir_transform/src/coverage/query.rs @@ -136,7 +136,7 @@ fn coverageinfo<'tcx>(tcx: TyCtxt<'tcx>, instance_def: ty::InstanceDef<'tcx>) -> coverage_visitor.info } -fn covered_code_regions<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> Vec<&'tcx CodeRegion> { +fn covered_code_regions(tcx: TyCtxt<'_>, def_id: DefId) -> Vec<&CodeRegion> { let body = mir_body(tcx, def_id); body.basic_blocks .iter() @@ -163,7 +163,7 @@ fn is_inlined(body: &Body<'_>, statement: &Statement<'_>) -> bool { /// This function ensures we obtain the correct MIR for the given item irrespective of /// whether that means const mir or runtime mir. For `const fn` this opts for runtime /// mir. -fn mir_body<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> &'tcx mir::Body<'tcx> { +fn mir_body(tcx: TyCtxt<'_>, def_id: DefId) -> &mir::Body<'_> { let id = ty::WithOptConstParam::unknown(def_id); let def = ty::InstanceDef::Item(id); tcx.instance_mir(def) diff --git a/compiler/rustc_mir_transform/src/coverage/spans.rs b/compiler/rustc_mir_transform/src/coverage/spans.rs index 9f842c929..c54348404 100644 --- a/compiler/rustc_mir_transform/src/coverage/spans.rs +++ b/compiler/rustc_mir_transform/src/coverage/spans.rs @@ -341,11 +341,11 @@ impl<'a, 'tcx> CoverageSpans<'a, 'tcx> { if a.is_in_same_bcb(b) { Some(Ordering::Equal) } else { - // Sort equal spans by dominator relationship, in reverse order (so - // dominators always come after the dominated equal spans). When later - // comparing two spans in order, the first will either dominate the second, - // or they will have no dominator relationship. - self.basic_coverage_blocks.dominators().rank_partial_cmp(b.bcb, a.bcb) + // Sort equal spans by dominator relationship (so dominators always come + // before the dominated equal spans). When later comparing two spans in + // order, the first will either dominate the second, or they will have no + // dominator relationship. + self.basic_coverage_blocks.dominators().rank_partial_cmp(a.bcb, b.bcb) } } else { // Sort hi() in reverse order so shorter spans are attempted after longer spans. diff --git a/compiler/rustc_mir_transform/src/coverage/tests.rs b/compiler/rustc_mir_transform/src/coverage/tests.rs index 9c9ed5fa5..fa7f22303 100644 --- a/compiler/rustc_mir_transform/src/coverage/tests.rs +++ b/compiler/rustc_mir_transform/src/coverage/tests.rs @@ -37,7 +37,7 @@ use rustc_data_structures::graph::WithSuccessors; use rustc_index::vec::{Idx, IndexVec}; use rustc_middle::mir::coverage::CoverageKind; use rustc_middle::mir::*; -use rustc_middle::ty::{self, Ty, TyCtxt}; +use rustc_middle::ty; use rustc_span::{self, BytePos, Pos, Span, DUMMY_SP}; // All `TEMP_BLOCK` targets should be replaced before calling `to_body() -> mir::Body`. @@ -47,7 +47,6 @@ struct MockBlocks<'tcx> { blocks: IndexVec<BasicBlock, BasicBlockData<'tcx>>, dummy_place: Place<'tcx>, next_local: usize, - bool_ty: Ty<'tcx>, } impl<'tcx> MockBlocks<'tcx> { @@ -56,7 +55,6 @@ impl<'tcx> MockBlocks<'tcx> { blocks: IndexVec::new(), dummy_place: Place { local: RETURN_PLACE, projection: ty::List::empty() }, next_local: 0, - bool_ty: TyCtxt::BOOL_TY_FOR_UNIT_TESTING, } } @@ -157,7 +155,6 @@ impl<'tcx> MockBlocks<'tcx> { fn switchint(&mut self, some_from_block: Option<BasicBlock>) -> BasicBlock { let switchint_kind = TerminatorKind::SwitchInt { discr: Operand::Move(Place::from(self.new_temp())), - switch_ty: self.bool_ty, // just a dummy value targets: SwitchTargets::static_if(0, TEMP_BLOCK, TEMP_BLOCK), }; self.add_block_from(some_from_block, switchint_kind) @@ -172,7 +169,7 @@ impl<'tcx> MockBlocks<'tcx> { } } -fn debug_basic_blocks<'tcx>(mir_body: &Body<'tcx>) -> String { +fn debug_basic_blocks(mir_body: &Body<'_>) -> String { format!( "{:?}", mir_body diff --git a/compiler/rustc_mir_transform/src/dataflow_const_prop.rs b/compiler/rustc_mir_transform/src/dataflow_const_prop.rs index e90273874..c75fe2327 100644 --- a/compiler/rustc_mir_transform/src/dataflow_const_prop.rs +++ b/compiler/rustc_mir_transform/src/dataflow_const_prop.rs @@ -2,6 +2,7 @@ //! //! Currently, this pass only propagates scalar values. +use rustc_const_eval::const_eval::CheckAlignment; use rustc_const_eval::interpret::{ConstValue, ImmTy, Immediate, InterpCx, Scalar}; use rustc_data_structures::fx::FxHashMap; use rustc_middle::mir::visit::{MutVisitor, Visitor}; @@ -10,6 +11,7 @@ use rustc_middle::ty::{self, Ty, TyCtxt}; use rustc_mir_dataflow::value_analysis::{Map, State, TrackElem, ValueAnalysis, ValueOrPlace}; use rustc_mir_dataflow::{lattice::FlatSet, Analysis, ResultsVisitor, SwitchIntEdgeEffects}; use rustc_span::DUMMY_SP; +use rustc_target::abi::Align; use crate::MirPass; @@ -448,13 +450,21 @@ impl<'mir, 'tcx> rustc_const_eval::interpret::Machine<'mir, 'tcx> for DummyMachi type MemoryKind = !; const PANIC_ON_ALLOC_FAIL: bool = true; - fn enforce_alignment(_ecx: &InterpCx<'mir, 'tcx, Self>) -> bool { + fn enforce_alignment(_ecx: &InterpCx<'mir, 'tcx, Self>) -> CheckAlignment { unimplemented!() } fn enforce_validity(_ecx: &InterpCx<'mir, 'tcx, Self>) -> bool { unimplemented!() } + fn alignment_check_failed( + _ecx: &InterpCx<'mir, 'tcx, Self>, + _has: Align, + _required: Align, + _check: CheckAlignment, + ) -> interpret::InterpResult<'tcx, ()> { + unimplemented!() + } fn find_mir_or_eval_fn( _ecx: &mut InterpCx<'mir, 'tcx, Self>, diff --git a/compiler/rustc_mir_transform/src/dead_store_elimination.rs b/compiler/rustc_mir_transform/src/dead_store_elimination.rs index 42c580c63..09546330c 100644 --- a/compiler/rustc_mir_transform/src/dead_store_elimination.rs +++ b/compiler/rustc_mir_transform/src/dead_store_elimination.rs @@ -71,7 +71,7 @@ pub fn eliminate<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>, borrowed: &BitS bbs[block].statements[statement_index].make_nop(); } - crate::simplify::SimplifyLocals.run_pass(tcx, body) + crate::simplify::simplify_locals(body, tcx) } pub struct DeadStoreElimination; diff --git a/compiler/rustc_mir_transform/src/deduce_param_attrs.rs b/compiler/rustc_mir_transform/src/deduce_param_attrs.rs index 92f1fff6b..ddab7bbb2 100644 --- a/compiler/rustc_mir_transform/src/deduce_param_attrs.rs +++ b/compiler/rustc_mir_transform/src/deduce_param_attrs.rs @@ -129,7 +129,7 @@ impl<'tcx> Visitor<'tcx> for DeduceReadOnly { } /// Returns true if values of a given type will never be passed indirectly, regardless of ABI. -fn type_will_always_be_passed_directly<'tcx>(ty: Ty<'tcx>) -> bool { +fn type_will_always_be_passed_directly(ty: Ty<'_>) -> bool { matches!( ty.kind(), ty::Bool diff --git a/compiler/rustc_mir_transform/src/dest_prop.rs b/compiler/rustc_mir_transform/src/dest_prop.rs index 97485c4f5..08e296a83 100644 --- a/compiler/rustc_mir_transform/src/dest_prop.rs +++ b/compiler/rustc_mir_transform/src/dest_prop.rs @@ -129,18 +129,16 @@ use std::collections::hash_map::{Entry, OccupiedEntry}; +use crate::simplify::remove_dead_blocks; use crate::MirPass; use rustc_data_structures::fx::FxHashMap; use rustc_index::bit_set::BitSet; +use rustc_middle::mir::visit::{MutVisitor, PlaceContext, Visitor}; use rustc_middle::mir::{dump_mir, PassWhere}; use rustc_middle::mir::{ traversal, BasicBlock, Body, InlineAsmOperand, Local, LocalKind, Location, Operand, Place, Rvalue, Statement, StatementKind, TerminatorKind, }; -use rustc_middle::mir::{ - visit::{MutVisitor, PlaceContext, Visitor}, - ProjectionElem, -}; use rustc_middle::ty::TyCtxt; use rustc_mir_dataflow::impls::MaybeLiveLocals; use rustc_mir_dataflow::{Analysis, ResultsCursor}; @@ -238,6 +236,12 @@ impl<'tcx> MirPass<'tcx> for DestinationPropagation { apply_merges(body, tcx, &merges, &merged_locals); } + if round_count != 0 { + // Merging can introduce overlap between moved arguments and/or call destination in an + // unreachable code, which validator considers to be ill-formed. + remove_dead_blocks(tcx, body); + } + trace!(round_count); } } @@ -359,40 +363,45 @@ struct FilterInformation<'a, 'body, 'alloc, 'tcx> { // through these methods, and not directly. impl<'alloc> Candidates<'alloc> { /// Just `Vec::retain`, but the condition is inverted and we add debugging output - fn vec_remove_debug( + fn vec_filter_candidates( src: Local, v: &mut Vec<Local>, - mut f: impl FnMut(Local) -> bool, + mut f: impl FnMut(Local) -> CandidateFilter, at: Location, ) { v.retain(|dest| { let remove = f(*dest); - if remove { + if remove == CandidateFilter::Remove { trace!("eliminating {:?} => {:?} due to conflict at {:?}", src, dest, at); } - !remove + remove == CandidateFilter::Keep }); } - /// `vec_remove_debug` but for an `Entry` - fn entry_remove( + /// `vec_filter_candidates` but for an `Entry` + fn entry_filter_candidates( mut entry: OccupiedEntry<'_, Local, Vec<Local>>, p: Local, - f: impl FnMut(Local) -> bool, + f: impl FnMut(Local) -> CandidateFilter, at: Location, ) { let candidates = entry.get_mut(); - Self::vec_remove_debug(p, candidates, f, at); + Self::vec_filter_candidates(p, candidates, f, at); if candidates.len() == 0 { entry.remove(); } } - /// Removes all candidates `(p, q)` or `(q, p)` where `p` is the indicated local and `f(q)` is true. - fn remove_candidates_if(&mut self, p: Local, mut f: impl FnMut(Local) -> bool, at: Location) { + /// For all candidates `(p, q)` or `(q, p)` removes the candidate if `f(q)` says to do so + fn filter_candidates_by( + &mut self, + p: Local, + mut f: impl FnMut(Local) -> CandidateFilter, + at: Location, + ) { // Cover the cases where `p` appears as a `src` if let Entry::Occupied(entry) = self.c.entry(p) { - Self::entry_remove(entry, p, &mut f, at); + Self::entry_filter_candidates(entry, p, &mut f, at); } // And the cases where `p` appears as a `dest` let Some(srcs) = self.reverse.get_mut(&p) else { @@ -401,18 +410,31 @@ impl<'alloc> Candidates<'alloc> { // We use `retain` here to remove the elements from the reverse set if we've removed the // matching candidate in the forward set. srcs.retain(|src| { - if !f(*src) { + if f(*src) == CandidateFilter::Keep { return true; } let Entry::Occupied(entry) = self.c.entry(*src) else { return false; }; - Self::entry_remove(entry, *src, |dest| dest == p, at); + Self::entry_filter_candidates( + entry, + *src, + |dest| { + if dest == p { CandidateFilter::Remove } else { CandidateFilter::Keep } + }, + at, + ); false }); } } +#[derive(Copy, Clone, PartialEq, Eq)] +enum CandidateFilter { + Keep, + Remove, +} + impl<'a, 'body, 'alloc, 'tcx> FilterInformation<'a, 'body, 'alloc, 'tcx> { /// Filters the set of candidates to remove those that conflict. /// @@ -460,7 +482,7 @@ impl<'a, 'body, 'alloc, 'tcx> FilterInformation<'a, 'body, 'alloc, 'tcx> { for (i, statement) in data.statements.iter().enumerate().rev() { self.at = Location { block, statement_index: i }; self.live.seek_after_primary_effect(self.at); - self.get_statement_write_info(&statement.kind); + self.write_info.for_statement(&statement.kind, self.body); self.apply_conflicts(); } } @@ -469,80 +491,59 @@ impl<'a, 'body, 'alloc, 'tcx> FilterInformation<'a, 'body, 'alloc, 'tcx> { fn apply_conflicts(&mut self) { let writes = &self.write_info.writes; for p in writes { - self.candidates.remove_candidates_if( + let other_skip = self.write_info.skip_pair.and_then(|(a, b)| { + if a == *p { + Some(b) + } else if b == *p { + Some(a) + } else { + None + } + }); + self.candidates.filter_candidates_by( *p, - // It is possible that a local may be live for less than the - // duration of a statement This happens in the case of function - // calls or inline asm. Because of this, we also mark locals as - // conflicting when both of them are written to in the same - // statement. - |q| self.live.contains(q) || writes.contains(&q), + |q| { + if Some(q) == other_skip { + return CandidateFilter::Keep; + } + // It is possible that a local may be live for less than the + // duration of a statement This happens in the case of function + // calls or inline asm. Because of this, we also mark locals as + // conflicting when both of them are written to in the same + // statement. + if self.live.contains(q) || writes.contains(&q) { + CandidateFilter::Remove + } else { + CandidateFilter::Keep + } + }, self.at, ); } } - - /// Gets the write info for the `statement`. - fn get_statement_write_info(&mut self, statement: &StatementKind<'tcx>) { - self.write_info.writes.clear(); - match statement { - StatementKind::Assign(box (lhs, rhs)) => match rhs { - Rvalue::Use(op) => { - if !lhs.is_indirect() { - self.get_assign_use_write_info(*lhs, op); - return; - } - } - _ => (), - }, - _ => (), - } - - self.write_info.for_statement(statement); - } - - fn get_assign_use_write_info(&mut self, lhs: Place<'tcx>, rhs: &Operand<'tcx>) { - // We register the writes for the operand unconditionally - self.write_info.add_operand(rhs); - // However, we cannot do the same thing for the `lhs` as that would always block the - // optimization. Instead, we consider removing candidates manually. - let Some(rhs) = rhs.place() else { - self.write_info.add_place(lhs); - return; - }; - // Find out which candidate pair we should skip, if any - let Some((src, dest)) = places_to_candidate_pair(lhs, rhs, self.body) else { - self.write_info.add_place(lhs); - return; - }; - self.candidates.remove_candidates_if( - lhs.local, - |other| { - // Check if this is the candidate pair that should not be removed - if (lhs.local == src && other == dest) || (lhs.local == dest && other == src) { - return false; - } - // Otherwise, do the "standard" thing - self.live.contains(other) - }, - self.at, - ) - } } /// Describes where a statement/terminator writes to #[derive(Default, Debug)] struct WriteInfo { writes: Vec<Local>, + /// If this pair of locals is a candidate pair, completely skip processing it during this + /// statement. All other candidates are unaffected. + skip_pair: Option<(Local, Local)>, } impl WriteInfo { - fn for_statement<'tcx>(&mut self, statement: &StatementKind<'tcx>) { + fn for_statement<'tcx>(&mut self, statement: &StatementKind<'tcx>, body: &Body<'tcx>) { + self.reset(); match statement { StatementKind::Assign(box (lhs, rhs)) => { self.add_place(*lhs); match rhs { - Rvalue::Use(op) | Rvalue::Repeat(op, _) => { + Rvalue::Use(op) => { + self.add_operand(op); + self.consider_skipping_for_assign_use(*lhs, op, body); + } + Rvalue::Repeat(op, _) => { self.add_operand(op); } Rvalue::Cast(_, op, _) @@ -586,8 +587,22 @@ impl WriteInfo { } } + fn consider_skipping_for_assign_use<'tcx>( + &mut self, + lhs: Place<'tcx>, + rhs: &Operand<'tcx>, + body: &Body<'tcx>, + ) { + let Some(rhs) = rhs.place() else { + return + }; + if let Some(pair) = places_to_candidate_pair(lhs, rhs, body) { + self.skip_pair = Some(pair); + } + } + fn for_terminator<'tcx>(&mut self, terminator: &TerminatorKind<'tcx>) { - self.writes.clear(); + self.reset(); match terminator { TerminatorKind::SwitchInt { discr: op, .. } | TerminatorKind::Assert { cond: op, .. } => { @@ -643,7 +658,7 @@ impl WriteInfo { } } - fn add_place<'tcx>(&mut self, place: Place<'tcx>) { + fn add_place(&mut self, place: Place<'_>) { self.writes.push(place.local); } @@ -657,15 +672,16 @@ impl WriteInfo { Operand::Copy(_) | Operand::Constant(_) => (), } } + + fn reset(&mut self) { + self.writes.clear(); + self.skip_pair = None; + } } ///////////////////////////////////////////////////// // Candidate accumulation -fn is_constant<'tcx>(place: Place<'tcx>) -> bool { - place.projection.iter().all(|p| !matches!(p, ProjectionElem::Deref | ProjectionElem::Index(_))) -} - /// If the pair of places is being considered for merging, returns the candidate which would be /// merged in order to accomplish this. /// @@ -741,10 +757,6 @@ impl<'tcx> Visitor<'tcx> for FindAssignments<'_, '_, 'tcx> { Rvalue::Use(Operand::Copy(rhs) | Operand::Move(rhs)), )) = &statement.kind { - if !is_constant(*lhs) || !is_constant(*rhs) { - return; - } - let Some((src, dest)) = places_to_candidate_pair(*lhs, *rhs, self.body) else { return; }; diff --git a/compiler/rustc_mir_transform/src/early_otherwise_branch.rs b/compiler/rustc_mir_transform/src/early_otherwise_branch.rs index 32e738bbc..8a7b027dd 100644 --- a/compiler/rustc_mir_transform/src/early_otherwise_branch.rs +++ b/compiler/rustc_mir_transform/src/early_otherwise_branch.rs @@ -121,7 +121,6 @@ impl<'tcx> MirPass<'tcx> for EarlyOtherwiseBranch { let TerminatorKind::SwitchInt { discr: parent_op, - switch_ty: parent_ty, targets: parent_targets } = &bbs[parent].terminator().kind else { unreachable!() @@ -132,6 +131,7 @@ impl<'tcx> MirPass<'tcx> for EarlyOtherwiseBranch { Operand::Copy(x) => Operand::Copy(*x), Operand::Constant(x) => Operand::Constant(x.clone()), }; + let parent_ty = parent_op.ty(body.local_decls(), tcx); let statements_before = bbs[parent].statements.len(); let parent_end = Location { block: parent, statement_index: statements_before }; @@ -153,7 +153,7 @@ impl<'tcx> MirPass<'tcx> for EarlyOtherwiseBranch { // create temp to store inequality comparison between the two discriminants, `_t` in // example above let nequal = BinOp::Ne; - let comp_res_type = nequal.ty(tcx, *parent_ty, opt_data.child_ty); + let comp_res_type = nequal.ty(tcx, parent_ty, opt_data.child_ty); let comp_temp = patch.new_temp(comp_res_type, opt_data.child_source.span); patch.add_statement(parent_end, StatementKind::StorageLive(comp_temp)); @@ -181,7 +181,6 @@ impl<'tcx> MirPass<'tcx> for EarlyOtherwiseBranch { kind: TerminatorKind::SwitchInt { // switch on the first discriminant, so we can mark the second one as dead discr: parent_op, - switch_ty: opt_data.child_ty, targets: eq_targets, }, })); @@ -193,12 +192,7 @@ impl<'tcx> MirPass<'tcx> for EarlyOtherwiseBranch { let false_case = eq_bb; patch.patch_terminator( parent, - TerminatorKind::if_( - tcx, - Operand::Move(Place::from(comp_temp)), - true_case, - false_case, - ), + TerminatorKind::if_(Operand::Move(Place::from(comp_temp)), true_case, false_case), ); // generate StorageDead for the second_discriminant_temp not in use anymore @@ -319,11 +313,11 @@ fn evaluate_candidate<'tcx>( let bbs = &body.basic_blocks; let TerminatorKind::SwitchInt { targets, - switch_ty: parent_ty, - .. + discr: parent_discr, } = &bbs[parent].terminator().kind else { return None }; + let parent_ty = parent_discr.ty(body.local_decls(), tcx); let parent_dest = { let poss = targets.otherwise(); // If the fallthrough on the parent is trivially unreachable, we can let the @@ -339,12 +333,12 @@ fn evaluate_candidate<'tcx>( let (_, child) = targets.iter().next()?; let child_terminator = &bbs[child].terminator(); let TerminatorKind::SwitchInt { - switch_ty: child_ty, targets: child_targets, - .. + discr: child_discr, } = &child_terminator.kind else { return None }; + let child_ty = child_discr.ty(body.local_decls(), tcx); if child_ty != parent_ty { return None; } @@ -372,7 +366,7 @@ fn evaluate_candidate<'tcx>( Some(OptimizationData { destination, child_place: *child_place, - child_ty: *child_ty, + child_ty, child_source: child_terminator.source_info, }) } diff --git a/compiler/rustc_mir_transform/src/generator.rs b/compiler/rustc_mir_transform/src/generator.rs index 69f96fe48..39c61a34a 100644 --- a/compiler/rustc_mir_transform/src/generator.rs +++ b/compiler/rustc_mir_transform/src/generator.rs @@ -460,6 +460,104 @@ fn replace_local<'tcx>( new_local } +/// Transforms the `body` of the generator applying the following transforms: +/// +/// - Eliminates all the `get_context` calls that async lowering created. +/// - Replace all `Local` `ResumeTy` types with `&mut Context<'_>` (`context_mut_ref`). +/// +/// The `Local`s that have their types replaced are: +/// - The `resume` argument itself. +/// - The argument to `get_context`. +/// - The yielded value of a `yield`. +/// +/// The `ResumeTy` hides a `&mut Context<'_>` behind an unsafe raw pointer, and the +/// `get_context` function is being used to convert that back to a `&mut Context<'_>`. +/// +/// Ideally the async lowering would not use the `ResumeTy`/`get_context` indirection, +/// but rather directly use `&mut Context<'_>`, however that would currently +/// lead to higher-kinded lifetime errors. +/// See <https://github.com/rust-lang/rust/issues/105501>. +/// +/// The async lowering step and the type / lifetime inference / checking are +/// still using the `ResumeTy` indirection for the time being, and that indirection +/// is removed here. After this transform, the generator body only knows about `&mut Context<'_>`. +fn transform_async_context<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { + let context_mut_ref = tcx.mk_task_context(); + + // replace the type of the `resume` argument + replace_resume_ty_local(tcx, body, Local::new(2), context_mut_ref); + + let get_context_def_id = tcx.require_lang_item(LangItem::GetContext, None); + + for bb in BasicBlock::new(0)..body.basic_blocks.next_index() { + let bb_data = &body[bb]; + if bb_data.is_cleanup { + continue; + } + + match &bb_data.terminator().kind { + TerminatorKind::Call { func, .. } => { + let func_ty = func.ty(body, tcx); + if let ty::FnDef(def_id, _) = *func_ty.kind() { + if def_id == get_context_def_id { + let local = eliminate_get_context_call(&mut body[bb]); + replace_resume_ty_local(tcx, body, local, context_mut_ref); + } + } else { + continue; + } + } + TerminatorKind::Yield { resume_arg, .. } => { + replace_resume_ty_local(tcx, body, resume_arg.local, context_mut_ref); + } + _ => {} + } + } +} + +fn eliminate_get_context_call<'tcx>(bb_data: &mut BasicBlockData<'tcx>) -> Local { + let terminator = bb_data.terminator.take().unwrap(); + if let TerminatorKind::Call { mut args, destination, target, .. } = terminator.kind { + let arg = args.pop().unwrap(); + let local = arg.place().unwrap().local; + + let arg = Rvalue::Use(arg); + let assign = Statement { + source_info: terminator.source_info, + kind: StatementKind::Assign(Box::new((destination, arg))), + }; + bb_data.statements.push(assign); + bb_data.terminator = Some(Terminator { + source_info: terminator.source_info, + kind: TerminatorKind::Goto { target: target.unwrap() }, + }); + local + } else { + bug!(); + } +} + +#[cfg_attr(not(debug_assertions), allow(unused))] +fn replace_resume_ty_local<'tcx>( + tcx: TyCtxt<'tcx>, + body: &mut Body<'tcx>, + local: Local, + context_mut_ref: Ty<'tcx>, +) { + let local_ty = std::mem::replace(&mut body.local_decls[local].ty, context_mut_ref); + // We have to replace the `ResumeTy` that is used for type and borrow checking + // with `&mut Context<'_>` in MIR. + #[cfg(debug_assertions)] + { + if let ty::Adt(resume_ty_adt, _) = local_ty.kind() { + let expected_adt = tcx.adt_def(tcx.require_lang_item(LangItem::ResumeTy, None)); + assert_eq!(*resume_ty_adt, expected_adt); + } else { + panic!("expected `ResumeTy`, found `{:?}`", local_ty); + }; + } +} + struct LivenessInfo { /// Which locals are live across any suspension point. saved_locals: GeneratorSavedLocals, @@ -490,7 +588,7 @@ fn locals_live_across_suspend_points<'tcx>( // Calculate when MIR locals have live storage. This gives us an upper bound of their // lifetimes. - let mut storage_live = MaybeStorageLive::new(always_live_locals.clone()) + let mut storage_live = MaybeStorageLive::new(std::borrow::Cow::Borrowed(always_live_locals)) .into_engine(tcx, body_ref) .iterate_to_fixpoint() .into_results_cursor(body_ref); @@ -877,11 +975,7 @@ fn insert_switch<'tcx>( let (assign, discr) = transform.get_discr(body); let switch_targets = SwitchTargets::new(cases.iter().map(|(i, bb)| ((*i) as u128, *bb)), default_block); - let switch = TerminatorKind::SwitchInt { - discr: Operand::Move(discr), - switch_ty: transform.discr_ty, - targets: switch_targets, - }; + let switch = TerminatorKind::SwitchInt { discr: Operand::Move(discr), targets: switch_targets }; let source_info = SourceInfo::outermost(body.span); body.basic_blocks_mut().raw.insert( @@ -1287,13 +1381,13 @@ impl<'tcx> MirPass<'tcx> for StateTransform { } }; - let is_async_kind = body.generator_kind().unwrap() != GeneratorKind::Gen; + let is_async_kind = matches!(body.generator_kind(), Some(GeneratorKind::Async(_))); let (state_adt_ref, state_substs) = if is_async_kind { // Compute Poll<return_ty> - let state_did = tcx.require_lang_item(LangItem::Poll, None); - let state_adt_ref = tcx.adt_def(state_did); - let state_substs = tcx.intern_substs(&[body.return_ty().into()]); - (state_adt_ref, state_substs) + let poll_did = tcx.require_lang_item(LangItem::Poll, None); + let poll_adt_ref = tcx.adt_def(poll_did); + let poll_substs = tcx.intern_substs(&[body.return_ty().into()]); + (poll_adt_ref, poll_substs) } else { // Compute GeneratorState<yield_ty, return_ty> let state_did = tcx.require_lang_item(LangItem::GeneratorState, None); @@ -1307,13 +1401,19 @@ impl<'tcx> MirPass<'tcx> for StateTransform { // RETURN_PLACE then is a fresh unused local with type ret_ty. let new_ret_local = replace_local(RETURN_PLACE, ret_ty, body, tcx); + // Replace all occurrences of `ResumeTy` with `&mut Context<'_>` within async bodies. + if is_async_kind { + transform_async_context(tcx, body); + } + // We also replace the resume argument and insert an `Assign`. // This is needed because the resume argument `_2` might be live across a `yield`, in which // case there is no `Assign` to it that the transform can turn into a store to the generator // state. After the yield the slot in the generator state would then be uninitialized. let resume_local = Local::new(2); - let new_resume_local = - replace_local(resume_local, body.local_decls[resume_local].ty, body, tcx); + let resume_ty = + if is_async_kind { tcx.mk_task_context() } else { body.local_decls[resume_local].ty }; + let new_resume_local = replace_local(resume_local, resume_ty, body, tcx); // When first entering the generator, move the resume argument into its new local. let source_info = SourceInfo::outermost(body.span); diff --git a/compiler/rustc_mir_transform/src/inline.rs b/compiler/rustc_mir_transform/src/inline.rs index 220cf7df9..28c9080d3 100644 --- a/compiler/rustc_mir_transform/src/inline.rs +++ b/compiler/rustc_mir_transform/src/inline.rs @@ -1,6 +1,7 @@ //! Inlining pass for MIR functions use crate::deref_separator::deref_finder; use rustc_attr::InlineAttr; +use rustc_hir::def_id::DefId; use rustc_index::bit_set::BitSet; use rustc_index::vec::Idx; use rustc_middle::middle::codegen_fn_attrs::{CodegenFnAttrFlags, CodegenFnAttrs}; @@ -27,6 +28,8 @@ const RESUME_PENALTY: usize = 45; const UNKNOWN_SIZE_COST: usize = 10; +const TOP_DOWN_DEPTH_LIMIT: usize = 5; + pub struct Inline; #[derive(Copy, Clone, Debug)] @@ -86,8 +89,13 @@ fn inline<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) -> bool { let param_env = tcx.param_env_reveal_all_normalized(def_id); - let mut this = - Inliner { tcx, param_env, codegen_fn_attrs: tcx.codegen_fn_attrs(def_id), changed: false }; + let mut this = Inliner { + tcx, + param_env, + codegen_fn_attrs: tcx.codegen_fn_attrs(def_id), + history: Vec::new(), + changed: false, + }; let blocks = BasicBlock::new(0)..body.basic_blocks.next_index(); this.process_blocks(body, blocks); this.changed @@ -98,12 +106,26 @@ struct Inliner<'tcx> { param_env: ParamEnv<'tcx>, /// Caller codegen attributes. codegen_fn_attrs: &'tcx CodegenFnAttrs, + /// Stack of inlined instances. + /// We only check the `DefId` and not the substs because we want to + /// avoid inlining cases of polymorphic recursion. + /// The number of `DefId`s is finite, so checking history is enough + /// to ensure that we do not loop endlessly while inlining. + history: Vec<DefId>, /// Indicates that the caller body has been modified. changed: bool, } impl<'tcx> Inliner<'tcx> { fn process_blocks(&mut self, caller_body: &mut Body<'tcx>, blocks: Range<BasicBlock>) { + // How many callsites in this body are we allowed to inline? We need to limit this in order + // to prevent super-linear growth in MIR size + let inline_limit = match self.history.len() { + 0 => usize::MAX, + 1..=TOP_DOWN_DEPTH_LIMIT => 1, + _ => return, + }; + let mut inlined_count = 0; for bb in blocks { let bb_data = &caller_body[bb]; if bb_data.is_cleanup { @@ -122,12 +144,16 @@ impl<'tcx> Inliner<'tcx> { debug!("not-inlined {} [{}]", callsite.callee, reason); continue; } - Ok(_) => { + Ok(new_blocks) => { debug!("inlined {}", callsite.callee); self.changed = true; - // We could process the blocks returned by `try_inlining` here. However, that - // leads to exponential compile times due to the top-down nature of this kind - // of inlining. + inlined_count += 1; + if inlined_count == inline_limit { + return; + } + self.history.push(callsite.callee.def_id()); + self.process_blocks(caller_body, new_blocks); + self.history.pop(); } } } @@ -289,7 +315,7 @@ impl<'tcx> Inliner<'tcx> { ) -> Option<CallSite<'tcx>> { // Only consider direct calls to functions let terminator = bb_data.terminator(); - if let TerminatorKind::Call { ref func, target, .. } = terminator.kind { + if let TerminatorKind::Call { ref func, target, fn_span, .. } = terminator.kind { let func_ty = func.ty(caller_body, self.tcx); if let ty::FnDef(def_id, substs) = *func_ty.kind() { // To resolve an instance its substs have to be fully normalized. @@ -301,15 +327,14 @@ impl<'tcx> Inliner<'tcx> { return None; } + if self.history.contains(&callee.def_id()) { + return None; + } + let fn_sig = self.tcx.bound_fn_sig(def_id).subst(self.tcx, substs); + let source_info = SourceInfo { span: fn_span, ..terminator.source_info }; - return Some(CallSite { - callee, - fn_sig, - block: bb, - target, - source_info: terminator.source_info, - }); + return Some(CallSite { callee, fn_sig, block: bb, target, source_info }); } } @@ -517,6 +542,21 @@ impl<'tcx> Inliner<'tcx> { destination }; + // Always create a local to hold the destination, as `RETURN_PLACE` may appear + // where a full `Place` is not allowed. + let (remap_destination, destination_local) = if let Some(d) = dest.as_local() { + (false, d) + } else { + ( + true, + self.new_call_temp( + caller_body, + &callsite, + destination.ty(caller_body, self.tcx).ty, + ), + ) + }; + // Copy the arguments if needed. let args: Vec<_> = self.make_call_args(args, &callsite, caller_body, &callee_body); @@ -535,7 +575,7 @@ impl<'tcx> Inliner<'tcx> { new_locals: Local::new(caller_body.local_decls.len()).., new_scopes: SourceScope::new(caller_body.source_scopes.len()).., new_blocks: BasicBlock::new(caller_body.basic_blocks.len()).., - destination: dest, + destination: destination_local, callsite_scope: caller_body.source_scopes[callsite.source_info.scope].clone(), callsite, cleanup_block: cleanup, @@ -566,6 +606,16 @@ impl<'tcx> Inliner<'tcx> { // To avoid repeated O(n) insert, push any new statements to the end and rotate // the slice once. let mut n = 0; + if remap_destination { + caller_body[block].statements.push(Statement { + source_info: callsite.source_info, + kind: StatementKind::Assign(Box::new(( + dest, + Rvalue::Use(Operand::Move(destination_local.into())), + ))), + }); + n += 1; + } for local in callee_body.vars_and_temps_iter().rev() { if !callee_body.local_decls[local].internal && integrator.always_live_locals.contains(local) @@ -849,7 +899,7 @@ impl<'tcx> Visitor<'tcx> for CostChecker<'_, 'tcx> { }; let kind = match parent_ty.ty.kind() { - &ty::Opaque(def_id, substs) => { + &ty::Alias(ty::Opaque, ty::AliasTy { def_id, substs, .. }) => { self.tcx.bound_type_of(def_id).subst(self.tcx, substs).kind() } kind => kind, @@ -934,7 +984,7 @@ struct Integrator<'a, 'tcx> { new_locals: RangeFrom<Local>, new_scopes: RangeFrom<SourceScope>, new_blocks: RangeFrom<BasicBlock>, - destination: Place<'tcx>, + destination: Local, callsite_scope: SourceScopeData<'tcx>, callsite: &'a CallSite<'tcx>, cleanup_block: Option<BasicBlock>, @@ -947,7 +997,7 @@ struct Integrator<'a, 'tcx> { impl Integrator<'_, '_> { fn map_local(&self, local: Local) -> Local { let new = if local == RETURN_PLACE { - self.destination.local + self.destination } else { let idx = local.index() - 1; if idx < self.args.len() { @@ -1028,27 +1078,6 @@ impl<'tcx> MutVisitor<'tcx> for Integrator<'_, 'tcx> { *span = span.fresh_expansion(self.expn_data); } - fn visit_place(&mut self, place: &mut Place<'tcx>, context: PlaceContext, location: Location) { - for elem in place.projection { - // FIXME: Make sure that return place is not used in an indexing projection, since it - // won't be rebased as it is supposed to be. - assert_ne!(ProjectionElem::Index(RETURN_PLACE), elem); - } - - // If this is the `RETURN_PLACE`, we need to rebase any projections onto it. - let dest_proj_len = self.destination.projection.len(); - if place.local == RETURN_PLACE && dest_proj_len > 0 { - let mut projs = Vec::with_capacity(dest_proj_len + place.projection.len()); - projs.extend(self.destination.projection); - projs.extend(place.projection); - - place.projection = self.tcx.intern_place_elems(&*projs); - } - // Handles integrating any locals that occur in the base - // or projections - self.super_place(place, context, location) - } - fn visit_basic_block_data(&mut self, block: BasicBlock, data: &mut BasicBlockData<'tcx>) { self.in_cleanup_block = data.is_cleanup; self.super_basic_block_data(block, data); diff --git a/compiler/rustc_mir_transform/src/lib.rs b/compiler/rustc_mir_transform/src/lib.rs index 93200b288..20b7fdcfe 100644 --- a/compiler/rustc_mir_transform/src/lib.rs +++ b/compiler/rustc_mir_transform/src/lib.rs @@ -77,8 +77,6 @@ mod match_branches; mod multiple_return_terminators; mod normalize_array_len; mod nrvo; -// This pass is public to allow external drivers to perform MIR cleanup -pub mod remove_false_edges; mod remove_noop_landing_pads; mod remove_storage_markers; mod remove_uninit_drops; @@ -268,10 +266,7 @@ fn mir_const_qualif(tcx: TyCtxt<'_>, def: ty::WithOptConstParam<LocalDefId>) -> /// Make MIR ready for const evaluation. This is run on all MIR, not just on consts! /// FIXME(oli-obk): it's unclear whether we still need this phase (and its corresponding query). /// We used to have this for pre-miri MIR based const eval. -fn mir_const<'tcx>( - tcx: TyCtxt<'tcx>, - def: ty::WithOptConstParam<LocalDefId>, -) -> &'tcx Steal<Body<'tcx>> { +fn mir_const(tcx: TyCtxt<'_>, def: ty::WithOptConstParam<LocalDefId>) -> &Steal<Body<'_>> { if let Some(def) = def.try_upgrade(tcx) { return tcx.mir_const(def); } @@ -310,10 +305,10 @@ fn mir_const<'tcx>( } /// Compute the main MIR body and the list of MIR bodies of the promoteds. -fn mir_promoted<'tcx>( - tcx: TyCtxt<'tcx>, +fn mir_promoted( + tcx: TyCtxt<'_>, def: ty::WithOptConstParam<LocalDefId>, -) -> (&'tcx Steal<Body<'tcx>>, &'tcx Steal<IndexVec<Promoted, Body<'tcx>>>) { +) -> (&Steal<Body<'_>>, &Steal<IndexVec<Promoted, Body<'_>>>) { if let Some(def) = def.try_upgrade(tcx) { return tcx.mir_promoted(def); } @@ -352,7 +347,7 @@ fn mir_promoted<'tcx>( } /// Compute the MIR that is used during CTFE (and thus has no optimizations run on it) -fn mir_for_ctfe<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> &'tcx Body<'tcx> { +fn mir_for_ctfe(tcx: TyCtxt<'_>, def_id: DefId) -> &Body<'_> { let did = def_id.expect_local(); if let Some(def) = ty::WithOptConstParam::try_lookup(did, tcx) { tcx.mir_for_ctfe_of_const_arg(def) @@ -366,10 +361,7 @@ fn mir_for_ctfe<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> &'tcx Body<'tcx> { /// we'd get cycle errors with `mir_for_ctfe`, because typeck would need to typeck /// the const parameter while type checking the main body, which in turn would try /// to type check the main body again. -fn mir_for_ctfe_of_const_arg<'tcx>( - tcx: TyCtxt<'tcx>, - (did, param_did): (LocalDefId, DefId), -) -> &'tcx Body<'tcx> { +fn mir_for_ctfe_of_const_arg(tcx: TyCtxt<'_>, (did, param_did): (LocalDefId, DefId)) -> &Body<'_> { tcx.arena.alloc(inner_mir_for_ctfe( tcx, ty::WithOptConstParam { did, const_param_did: Some(param_did) }, @@ -426,10 +418,10 @@ fn inner_mir_for_ctfe(tcx: TyCtxt<'_>, def: ty::WithOptConstParam<LocalDefId>) - /// Obtain just the main MIR (no promoteds) and run some cleanups on it. This also runs /// mir borrowck *before* doing so in order to ensure that borrowck can be run and doesn't /// end up missing the source MIR due to stealing happening. -fn mir_drops_elaborated_and_const_checked<'tcx>( - tcx: TyCtxt<'tcx>, +fn mir_drops_elaborated_and_const_checked( + tcx: TyCtxt<'_>, def: ty::WithOptConstParam<LocalDefId>, -) -> &'tcx Steal<Body<'tcx>> { +) -> &Steal<Body<'_>> { if let Some(def) = def.try_upgrade(tcx) { return tcx.mir_drops_elaborated_and_const_checked(def); } @@ -494,10 +486,8 @@ fn run_analysis_to_runtime_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx> /// After this series of passes, no lifetime analysis based on borrowing can be done. fn run_analysis_cleanup_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { let passes: &[&dyn MirPass<'tcx>] = &[ - &remove_false_edges::RemoveFalseEdges, - &simplify_branches::SimplifyConstCondition::new("initial"), + &cleanup_post_borrowck::CleanupPostBorrowck, &remove_noop_landing_pads::RemoveNoopLandingPads, - &cleanup_post_borrowck::CleanupNonCodegenStatements, &simplify::SimplifyCfg::new("early-opt"), &deref_separator::Derefer, ]; @@ -533,11 +523,8 @@ fn run_runtime_lowering_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { /// Returns the sequence of passes that do the initial cleanup of runtime MIR. fn run_runtime_cleanup_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { - let passes: &[&dyn MirPass<'tcx>] = &[ - &elaborate_box_derefs::ElaborateBoxDerefs, - &lower_intrinsics::LowerIntrinsics, - &simplify::SimplifyCfg::new("elaborate-drops"), - ]; + let passes: &[&dyn MirPass<'tcx>] = + &[&lower_intrinsics::LowerIntrinsics, &simplify::SimplifyCfg::new("elaborate-drops")]; pm::run_passes(tcx, body, passes, Some(MirPhase::Runtime(RuntimePhase::PostCleanup))); } @@ -569,6 +556,7 @@ fn run_optimization_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { &multiple_return_terminators::MultipleReturnTerminators, &instcombine::InstCombine, &separate_const_switch::SeparateConstSwitch, + &simplify::SimplifyLocals::new("before-const-prop"), // // FIXME(#70073): This pass is responsible for both optimization as well as some lints. &const_prop::ConstProp, @@ -587,7 +575,7 @@ fn run_optimization_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { &o1(remove_noop_landing_pads::RemoveNoopLandingPads), &o1(simplify::SimplifyCfg::new("final")), &nrvo::RenameReturnPlace, - &simplify::SimplifyLocals, + &simplify::SimplifyLocals::new("final"), &multiple_return_terminators::MultipleReturnTerminators, &deduplicate_blocks::DeduplicateBlocks, // Some cleanup necessary at least for LLVM and potentially other codegen backends. @@ -600,7 +588,7 @@ fn run_optimization_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { } /// Optimize the MIR and prepare it for codegen. -fn optimized_mir<'tcx>(tcx: TyCtxt<'tcx>, did: DefId) -> &'tcx Body<'tcx> { +fn optimized_mir(tcx: TyCtxt<'_>, did: DefId) -> &Body<'_> { let did = did.expect_local(); assert_eq!(ty::WithOptConstParam::try_lookup(did, tcx), None); tcx.arena.alloc(inner_optimized_mir(tcx, did)) @@ -637,10 +625,10 @@ fn inner_optimized_mir(tcx: TyCtxt<'_>, did: LocalDefId) -> Body<'_> { /// Fetch all the promoteds of an item and prepare their MIR bodies to be ready for /// constant evaluation once all substitutions become known. -fn promoted_mir<'tcx>( - tcx: TyCtxt<'tcx>, +fn promoted_mir( + tcx: TyCtxt<'_>, def: ty::WithOptConstParam<LocalDefId>, -) -> &'tcx IndexVec<Promoted, Body<'tcx>> { +) -> &IndexVec<Promoted, Body<'_>> { if tcx.is_constructor(def.did.to_def_id()) { return tcx.arena.alloc(IndexVec::new()); } diff --git a/compiler/rustc_mir_transform/src/match_branches.rs b/compiler/rustc_mir_transform/src/match_branches.rs index a0ba69c89..ce05db5b7 100644 --- a/compiler/rustc_mir_transform/src/match_branches.rs +++ b/compiler/rustc_mir_transform/src/match_branches.rs @@ -55,10 +55,9 @@ impl<'tcx> MirPass<'tcx> for MatchBranchSimplification { continue; } - let (discr, val, switch_ty, first, second) = match bbs[bb_idx].terminator().kind { + let (discr, val, first, second) = match bbs[bb_idx].terminator().kind { TerminatorKind::SwitchInt { discr: ref discr @ (Operand::Copy(_) | Operand::Move(_)), - switch_ty, ref targets, .. } if targets.iter().len() == 1 => { @@ -66,7 +65,7 @@ impl<'tcx> MirPass<'tcx> for MatchBranchSimplification { if target == targets.otherwise() { continue; } - (discr, value, switch_ty, target, targets.otherwise()) + (discr, value, target, targets.otherwise()) } // Only optimize switch int statements _ => continue, @@ -105,10 +104,11 @@ impl<'tcx> MirPass<'tcx> for MatchBranchSimplification { } // Take ownership of items now that we know we can optimize. let discr = discr.clone(); + let discr_ty = discr.ty(&body.local_decls, tcx); // Introduce a temporary for the discriminant value. let source_info = bbs[bb_idx].terminator().source_info; - let discr_local = body.local_decls.push(LocalDecl::new(switch_ty, source_info.span)); + let discr_local = body.local_decls.push(LocalDecl::new(discr_ty, source_info.span)); // We already checked that first and second are different blocks, // and bb_idx has a different terminator from both of them. @@ -130,10 +130,10 @@ impl<'tcx> MirPass<'tcx> for MatchBranchSimplification { (*f).clone() } else { // Different value between blocks. Make value conditional on switch condition. - let size = tcx.layout_of(param_env.and(switch_ty)).unwrap().size; + let size = tcx.layout_of(param_env.and(discr_ty)).unwrap().size; let const_cmp = Operand::const_from_scalar( tcx, - switch_ty, + discr_ty, rustc_const_eval::interpret::Scalar::from_uint(val, size), rustc_span::DUMMY_SP, ); diff --git a/compiler/rustc_mir_transform/src/normalize_array_len.rs b/compiler/rustc_mir_transform/src/normalize_array_len.rs index a159e6171..1708b287e 100644 --- a/compiler/rustc_mir_transform/src/normalize_array_len.rs +++ b/compiler/rustc_mir_transform/src/normalize_array_len.rs @@ -16,7 +16,8 @@ pub struct NormalizeArrayLen; impl<'tcx> MirPass<'tcx> for NormalizeArrayLen { fn is_enabled(&self, sess: &rustc_session::Session) -> bool { - sess.mir_opt_level() >= 4 + // See #105929 + sess.mir_opt_level() >= 4 && sess.opts.unstable_opts.unsound_mir_opts } fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { diff --git a/compiler/rustc_mir_transform/src/remove_false_edges.rs b/compiler/rustc_mir_transform/src/remove_false_edges.rs deleted file mode 100644 index 71f5ccf7e..000000000 --- a/compiler/rustc_mir_transform/src/remove_false_edges.rs +++ /dev/null @@ -1,29 +0,0 @@ -use rustc_middle::mir::{Body, TerminatorKind}; -use rustc_middle::ty::TyCtxt; - -use crate::MirPass; - -/// Removes `FalseEdge` and `FalseUnwind` terminators from the MIR. -/// -/// These are only needed for borrow checking, and can be removed afterwards. -/// -/// FIXME: This should probably have its own MIR phase. -pub struct RemoveFalseEdges; - -impl<'tcx> MirPass<'tcx> for RemoveFalseEdges { - fn run_pass(&self, _: TyCtxt<'tcx>, body: &mut Body<'tcx>) { - for block in body.basic_blocks_mut() { - let terminator = block.terminator_mut(); - terminator.kind = match terminator.kind { - TerminatorKind::FalseEdge { real_target, .. } => { - TerminatorKind::Goto { target: real_target } - } - TerminatorKind::FalseUnwind { real_target, .. } => { - TerminatorKind::Goto { target: real_target } - } - - _ => continue, - } - } - } -} diff --git a/compiler/rustc_mir_transform/src/remove_zsts.rs b/compiler/rustc_mir_transform/src/remove_zsts.rs index 569e783fe..6cabef92d 100644 --- a/compiler/rustc_mir_transform/src/remove_zsts.rs +++ b/compiler/rustc_mir_transform/src/remove_zsts.rs @@ -52,7 +52,11 @@ impl<'tcx> MirPass<'tcx> for RemoveZsts { fn maybe_zst(ty: Ty<'_>) -> bool { match ty.kind() { // maybe ZST (could be more precise) - ty::Adt(..) | ty::Array(..) | ty::Closure(..) | ty::Tuple(..) | ty::Opaque(..) => true, + ty::Adt(..) + | ty::Array(..) + | ty::Closure(..) + | ty::Tuple(..) + | ty::Alias(ty::Opaque, ..) => true, // definitely ZST ty::FnDef(..) | ty::Never => true, // unreachable or can't be ZST diff --git a/compiler/rustc_mir_transform/src/shim.rs b/compiler/rustc_mir_transform/src/shim.rs index 16b7dcad1..dace540fa 100644 --- a/compiler/rustc_mir_transform/src/shim.rs +++ b/compiler/rustc_mir_transform/src/shim.rs @@ -174,9 +174,36 @@ fn build_drop_shim<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId, ty: Option<Ty<'tcx>>) let mut body = new_body(source, blocks, local_decls_for_sig(&sig, span), sig.inputs().len(), span); + // The first argument (index 0), but add 1 for the return value. + let mut dropee_ptr = Place::from(Local::new(1 + 0)); + if tcx.sess.opts.unstable_opts.mir_emit_retag { + // We want to treat the function argument as if it was passed by `&mut`. As such, we + // generate + // ``` + // temp = &mut *arg; + // Retag(temp, FnEntry) + // ``` + // It's important that we do this first, before anything that depends on `dropee_ptr` + // has been put into the body. + let reborrow = Rvalue::Ref( + tcx.lifetimes.re_erased, + BorrowKind::Mut { allow_two_phase_borrow: false }, + 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() { - // The first argument (index 0), but add 1 for the return value. - let dropee_ptr = Place::from(Local::new(1 + 0)); let patch = { let param_env = tcx.param_env_reveal_all_normalized(def_id); let mut elaborator = @@ -336,8 +363,7 @@ impl<'tcx> CloneShimBuilder<'tcx> { // we must subst the self_ty because it's // otherwise going to be TySelf and we can't index // or access fields of a Place of type TySelf. - let substs = tcx.mk_substs_trait(self_ty, []); - let sig = tcx.bound_fn_sig(def_id).subst(tcx, substs); + let sig = tcx.bound_fn_sig(def_id).subst(tcx, &[self_ty.into()]); let sig = tcx.erase_late_bound_regions(sig); let span = tcx.def_span(def_id); @@ -417,10 +443,8 @@ impl<'tcx> CloneShimBuilder<'tcx> { ) { let tcx = self.tcx; - let substs = tcx.mk_substs_trait(ty, []); - // `func == Clone::clone(&ty) -> ty` - let func_ty = tcx.mk_fn_def(self.def_id, substs); + let func_ty = tcx.mk_fn_def(self.def_id, [ty]); let func = Operand::Constant(Box::new(Constant { span: self.span, user_ty: None, @@ -548,7 +572,6 @@ impl<'tcx> CloneShimBuilder<'tcx> { statements.push(statement); *kind = TerminatorKind::SwitchInt { discr: Operand::Move(temp), - switch_ty: discr_ty, targets: SwitchTargets::new(cases.into_iter(), unreachable), }; } @@ -576,9 +599,8 @@ fn build_call_shim<'tcx>( // 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)) + (Some([ty.into(), arg_tup.into()]), Some(untuple_args)) } else { (None, None) }; @@ -589,7 +611,7 @@ fn build_call_shim<'tcx>( 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 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 diff --git a/compiler/rustc_mir_transform/src/simplify.rs b/compiler/rustc_mir_transform/src/simplify.rs index 475e2ec9a..8f6abe7a9 100644 --- a/compiler/rustc_mir_transform/src/simplify.rs +++ b/compiler/rustc_mir_transform/src/simplify.rs @@ -35,7 +35,6 @@ use rustc_middle::mir::visit::{MutVisitor, MutatingUseContext, PlaceContext, Vis use rustc_middle::mir::*; use rustc_middle::ty::TyCtxt; use smallvec::SmallVec; -use std::convert::TryInto; pub struct SimplifyCfg { label: String, @@ -380,9 +379,21 @@ fn save_unreachable_coverage( )); } -pub struct SimplifyLocals; +pub struct SimplifyLocals { + label: String, +} + +impl SimplifyLocals { + pub fn new(label: &str) -> SimplifyLocals { + SimplifyLocals { label: format!("SimplifyLocals-{}", label) } + } +} impl<'tcx> MirPass<'tcx> for SimplifyLocals { + fn name(&self) -> &str { + &self.label + } + fn is_enabled(&self, sess: &rustc_session::Session) -> bool { sess.mir_opt_level() > 0 } @@ -558,6 +569,7 @@ fn remove_unused_definitions(used_locals: &mut UsedLocals, body: &mut Body<'_>) StatementKind::SetDiscriminant { ref place, .. } | StatementKind::Deinit(ref place) => used_locals.is_used(place.local), + StatementKind::Nop => false, _ => true, }; diff --git a/compiler/rustc_mir_transform/src/simplify_branches.rs b/compiler/rustc_mir_transform/src/simplify_branches.rs index 405ebce4d..8164b3052 100644 --- a/compiler/rustc_mir_transform/src/simplify_branches.rs +++ b/compiler/rustc_mir_transform/src/simplify_branches.rs @@ -24,12 +24,9 @@ impl<'tcx> MirPass<'tcx> for SimplifyConstCondition { let terminator = block.terminator_mut(); terminator.kind = match terminator.kind { TerminatorKind::SwitchInt { - discr: Operand::Constant(ref c), - switch_ty, - ref targets, - .. + discr: Operand::Constant(ref c), ref targets, .. } => { - let constant = c.literal.try_eval_bits(tcx, param_env, switch_ty); + let constant = c.literal.try_eval_bits(tcx, param_env, c.ty()); if let Some(constant) = constant { let target = targets.target_for_value(constant); TerminatorKind::Goto { target } diff --git a/compiler/rustc_mir_transform/src/simplify_comparison_integral.rs b/compiler/rustc_mir_transform/src/simplify_comparison_integral.rs index 321d8c63b..dcad1518e 100644 --- a/compiler/rustc_mir_transform/src/simplify_comparison_integral.rs +++ b/compiler/rustc_mir_transform/src/simplify_comparison_integral.rs @@ -127,11 +127,8 @@ impl<'tcx> MirPass<'tcx> for SimplifyComparisonIntegral { let targets = SwitchTargets::new(iter::once((new_value, bb_cond)), bb_otherwise); let terminator = bb.terminator_mut(); - terminator.kind = TerminatorKind::SwitchInt { - discr: Operand::Move(opt.to_switch_on), - switch_ty: opt.branch_value_ty, - targets, - }; + terminator.kind = + TerminatorKind::SwitchInt { discr: Operand::Move(opt.to_switch_on), targets }; } for (idx, bb_idx) in storage_deads_to_remove { diff --git a/compiler/rustc_mir_transform/src/simplify_try.rs b/compiler/rustc_mir_transform/src/simplify_try.rs index baeb620ef..e4f3ace9a 100644 --- a/compiler/rustc_mir_transform/src/simplify_try.rs +++ b/compiler/rustc_mir_transform/src/simplify_try.rs @@ -532,7 +532,7 @@ struct VarField<'tcx> { } /// Match on `((_LOCAL as Variant).FIELD: TY)`. -fn match_variant_field_place<'tcx>(place: Place<'tcx>) -> Option<(Local, VarField<'tcx>)> { +fn match_variant_field_place(place: Place<'_>) -> Option<(Local, VarField<'_>)> { match place.as_ref() { PlaceRef { local, diff --git a/compiler/rustc_mir_transform/src/sroa.rs b/compiler/rustc_mir_transform/src/sroa.rs index 558a372fb..42124f5a4 100644 --- a/compiler/rustc_mir_transform/src/sroa.rs +++ b/compiler/rustc_mir_transform/src/sroa.rs @@ -182,7 +182,7 @@ fn replace_flattened_locals<'tcx>( let mut fragments = IndexVec::new(); for (k, v) in &replacements.fields { fragments.ensure_contains_elem(k.local, || Vec::new()); - fragments[k.local].push((&k.projection[..], *v)); + fragments[k.local].push((k.projection, *v)); } debug!(?fragments); @@ -215,7 +215,7 @@ struct ReplacementVisitor<'tcx, 'll> { replacements: ReplacementMap<'tcx>, /// This is used to check that we are not leaving references to replaced locals behind. all_dead_locals: BitSet<Local>, - /// Pre-computed list of all "new" locals for each "old" local. This is used to expand storage + /// Pre-computed list of all "new" locals for each "old" local. This is used to expand storage /// and deinit statement and debuginfo. fragments: IndexVec<Local, Vec<(&'tcx [PlaceElem<'tcx>], Local)>>, } diff --git a/compiler/rustc_mir_transform/src/unreachable_prop.rs b/compiler/rustc_mir_transform/src/unreachable_prop.rs index 95fda2eaf..d4b1cfe43 100644 --- a/compiler/rustc_mir_transform/src/unreachable_prop.rs +++ b/compiler/rustc_mir_transform/src/unreachable_prop.rs @@ -76,7 +76,7 @@ where let terminator = match terminator_kind { // This will unconditionally run into an unreachable and is therefore unreachable as well. TerminatorKind::Goto { target } if is_unreachable(*target) => TerminatorKind::Unreachable, - TerminatorKind::SwitchInt { targets, discr, switch_ty } => { + TerminatorKind::SwitchInt { targets, discr } => { let otherwise = targets.otherwise(); // If all targets are unreachable, we can be unreachable as well. @@ -87,7 +87,7 @@ where // unless otherwise is unreachable, in which case deleting a normal branch causes it to be merged with // the otherwise, keeping its unreachable. // This looses information about reachability causing worse codegen. - // For example (see src/test/codegen/match-optimizes-away.rs) + // For example (see tests/codegen/match-optimizes-away.rs) // // pub enum Two { A, B } // pub fn identity(x: Two) -> Two { @@ -110,11 +110,7 @@ where return None; } - TerminatorKind::SwitchInt { - discr: discr.clone(), - switch_ty: *switch_ty, - targets: new_targets, - } + TerminatorKind::SwitchInt { discr: discr.clone(), targets: new_targets } } else { // If the otherwise branch is reachable, we don't want to delete any unreachable branches. return None; |