From ef24de24a82fe681581cc130f342363c47c0969a Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Fri, 7 Jun 2024 07:48:48 +0200 Subject: Merging upstream version 1.75.0+dfsg1. Signed-off-by: Daniel Baumann --- compiler/rustc_mir_transform/src/lib.rs | 130 ++++++++++++++++++++++---------- 1 file changed, 89 insertions(+), 41 deletions(-) (limited to 'compiler/rustc_mir_transform/src/lib.rs') diff --git a/compiler/rustc_mir_transform/src/lib.rs b/compiler/rustc_mir_transform/src/lib.rs index c0a09b7a7..bf5f0ca7c 100644 --- a/compiler/rustc_mir_transform/src/lib.rs +++ b/compiler/rustc_mir_transform/src/lib.rs @@ -2,6 +2,7 @@ #![deny(rustc::untranslatable_diagnostic)] #![deny(rustc::diagnostic_outside_of_impl)] #![feature(box_patterns)] +#![feature(cow_is_borrowed)] #![feature(decl_macro)] #![feature(is_sorted)] #![feature(let_chains)] @@ -20,6 +21,7 @@ extern crate tracing; #[macro_use] extern crate rustc_middle; +use hir::ConstContext; use required_consts::RequiredConstsVisitor; use rustc_const_eval::util; use rustc_data_structures::fx::FxIndexSet; @@ -61,7 +63,10 @@ mod const_goto; mod const_prop; mod const_prop_lint; mod copy_prop; +mod coroutine; +mod cost_checker; mod coverage; +mod cross_crate_inline; mod ctfe_limit; mod dataflow_const_prop; mod dead_store_elimination; @@ -76,10 +81,10 @@ mod elaborate_drops; mod errors; mod ffi_unwind_calls; mod function_item_references; -mod generator; mod gvn; pub mod inline; mod instsimplify; +mod jump_threading; mod large_enums; mod lower_intrinsics; mod lower_slice_len; @@ -123,6 +128,7 @@ pub fn provide(providers: &mut Providers) { coverage::query::provide(providers); ffi_unwind_calls::provide(providers); shim::provide(providers); + cross_crate_inline::provide(providers); *providers = Providers { mir_keys, mir_const, @@ -130,7 +136,7 @@ pub fn provide(providers: &mut Providers) { mir_promoted, mir_drops_elaborated_and_const_checked, mir_for_ctfe, - mir_generator_witnesses: generator::mir_generator_witnesses, + mir_coroutine_witnesses: coroutine::mir_coroutine_witnesses, optimized_mir, is_mir_available, is_ctfe_mir_available: |tcx, did| is_mir_available(tcx, did), @@ -162,37 +168,50 @@ fn remap_mir_for_const_eval_select<'tcx>( && tcx.item_name(def_id) == sym::const_eval_select && tcx.is_intrinsic(def_id) => { - let [tupled_args, called_in_const, called_at_rt]: [_; 3] = std::mem::take(args).try_into().unwrap(); + let [tupled_args, called_in_const, called_at_rt]: [_; 3] = + std::mem::take(args).try_into().unwrap(); let ty = tupled_args.ty(&body.local_decls, tcx); let fields = ty.tuple_fields(); let num_args = fields.len(); - let func = if context == hir::Constness::Const { called_in_const } else { called_at_rt }; - let (method, place): (fn(Place<'tcx>) -> Operand<'tcx>, Place<'tcx>) = match tupled_args { - Operand::Constant(_) => { - // there is no good way of extracting a tuple arg from a constant (const generic stuff) - // so we just create a temporary and deconstruct that. - let local = body.local_decls.push(LocalDecl::new(ty, fn_span)); - bb.statements.push(Statement { - source_info: SourceInfo::outermost(fn_span), - kind: StatementKind::Assign(Box::new((local.into(), Rvalue::Use(tupled_args.clone())))), - }); - (Operand::Move, local.into()) - } - Operand::Move(place) => (Operand::Move, place), - Operand::Copy(place) => (Operand::Copy, place), - }; - let place_elems = place.projection; - let arguments = (0..num_args).map(|x| { - let mut place_elems = place_elems.to_vec(); - place_elems.push(ProjectionElem::Field(x.into(), fields[x])); - let projection = tcx.mk_place_elems(&place_elems); - let place = Place { - local: place.local, - projection, + let func = + if context == hir::Constness::Const { called_in_const } else { called_at_rt }; + let (method, place): (fn(Place<'tcx>) -> Operand<'tcx>, Place<'tcx>) = + match tupled_args { + Operand::Constant(_) => { + // there is no good way of extracting a tuple arg from a constant (const generic stuff) + // so we just create a temporary and deconstruct that. + let local = body.local_decls.push(LocalDecl::new(ty, fn_span)); + bb.statements.push(Statement { + source_info: SourceInfo::outermost(fn_span), + kind: StatementKind::Assign(Box::new(( + local.into(), + Rvalue::Use(tupled_args.clone()), + ))), + }); + (Operand::Move, local.into()) + } + Operand::Move(place) => (Operand::Move, place), + Operand::Copy(place) => (Operand::Copy, place), }; - method(place) - }).collect(); - terminator.kind = TerminatorKind::Call { func, args: arguments, destination, target, unwind, call_source: CallSource::Misc, fn_span }; + let place_elems = place.projection; + let arguments = (0..num_args) + .map(|x| { + let mut place_elems = place_elems.to_vec(); + place_elems.push(ProjectionElem::Field(x.into(), fields[x])); + let projection = tcx.mk_place_elems(&place_elems); + let place = Place { local: place.local, projection }; + method(place) + }) + .collect(); + terminator.kind = TerminatorKind::Call { + func, + args: arguments, + destination, + target, + unwind, + call_source: CallSource::Misc, + fn_span, + }; } _ => {} } @@ -234,8 +253,13 @@ fn mir_const_qualif(tcx: TyCtxt<'_>, def: LocalDefId) -> ConstQualifs { let const_kind = tcx.hir().body_const_context(def); // No need to const-check a non-const `fn`. - if const_kind.is_none() { - return Default::default(); + match const_kind { + Some(ConstContext::Const { .. } | ConstContext::Static(_)) + | Some(ConstContext::ConstFn) => {} + None => span_bug!( + tcx.def_span(def), + "`mir_const_qualif` should only be called on const fns and const items" + ), } // N.B., this `borrow()` is guaranteed to be valid (i.e., the value @@ -300,7 +324,21 @@ fn mir_promoted( // Ensure that we compute the `mir_const_qualif` for constants at // this point, before we steal the mir-const result. // Also this means promotion can rely on all const checks having been done. - let const_qualifs = tcx.mir_const_qualif(def); + + let const_qualifs = match tcx.def_kind(def) { + DefKind::Fn | DefKind::AssocFn | DefKind::Closure + if tcx.constness(def) == hir::Constness::Const + || tcx.is_const_default_method(def.to_def_id()) => + { + tcx.mir_const_qualif(def) + } + DefKind::AssocConst + | DefKind::Const + | DefKind::Static(_) + | DefKind::InlineConst + | DefKind::AnonConst => tcx.mir_const_qualif(def), + _ => ConstQualifs::default(), + }; let mut body = tcx.mir_const(def).steal(); if let Some(error_reported) = const_qualifs.tainted_by_errors { body.tainted_by_errors = Some(error_reported); @@ -360,15 +398,15 @@ fn inner_mir_for_ctfe(tcx: TyCtxt<'_>, def: LocalDefId) -> Body<'_> { /// 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: TyCtxt<'_>, def: LocalDefId) -> &Steal> { - if let DefKind::Generator = tcx.def_kind(def) { - tcx.ensure_with_value().mir_generator_witnesses(def); + if let DefKind::Coroutine = tcx.def_kind(def) { + tcx.ensure_with_value().mir_coroutine_witnesses(def); } let mir_borrowck = tcx.mir_borrowck(def); let is_fn_like = tcx.def_kind(def).is_fn_like(); if is_fn_like { // Do not compute the mir call graph without said call graph actually being used. - if inline::Inline.is_enabled(&tcx.sess) { + if pm::should_run_pass(tcx, &inline::Inline) { tcx.ensure_with_value().mir_inliner_callees(ty::InstanceDef::Item(def.to_def_id())); } } @@ -494,9 +532,9 @@ fn run_runtime_lowering_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { // `AddRetag` needs to run after `ElaborateDrops`. Otherwise it should run fairly late, // but before optimizations begin. &elaborate_box_derefs::ElaborateBoxDerefs, - &generator::StateTransform, + &coroutine::StateTransform, &add_retag::AddRetag, - &Lint(const_prop_lint::ConstProp), + &Lint(const_prop_lint::ConstPropLint), ]; pm::run_passes_no_validate(tcx, body, passes, Some(MirPhase::Runtime(RuntimePhase::Initial))); } @@ -530,10 +568,11 @@ fn run_optimization_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { &[ &check_alignment::CheckAlignment, &lower_slice_len::LowerSliceLenCalls, // has to be done before inlining, otherwise actual call will be almost always inlined. Also simple, so can just do first - &unreachable_prop::UnreachablePropagation, + &inline::Inline, + // Substitutions during inlining may introduce switch on enums with uninhabited branches. &uninhabited_enum_branching::UninhabitedEnumBranching, + &unreachable_prop::UnreachablePropagation, &o1(simplify::SimplifyCfg::AfterUninhabitedEnumBranching), - &inline::Inline, &remove_storage_markers::RemoveStorageMarkers, &remove_zsts::RemoveZsts, &normalize_array_len::NormalizeArrayLen, // has to run after `slice::len` lowering @@ -553,11 +592,11 @@ fn run_optimization_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { &separate_const_switch::SeparateConstSwitch, &const_prop::ConstProp, &gvn::GVN, + &simplify::SimplifyLocals::AfterGVN, &dataflow_const_prop::DataflowConstProp, - // - // Const-prop runs unconditionally, but doesn't mutate the MIR at mir-opt-level=0. &const_debuginfo::ConstDebugInfo, &o1(simplify_branches::SimplifyConstCondition::AfterConstProp), + &jump_threading::JumpThreading, &early_otherwise_branch::EarlyOtherwiseBranch, &simplify_comparison_integral::SimplifyComparisonIntegral, &dead_store_elimination::DeadStoreElimination, @@ -613,6 +652,15 @@ fn inner_optimized_mir(tcx: TyCtxt<'_>, did: LocalDefId) -> Body<'_> { return body; } + // If `mir_drops_elaborated_and_const_checked` found that the current body has unsatisfiable + // predicates, it will shrink the MIR to a single `unreachable` terminator. + // More generally, if MIR is a lone `unreachable`, there is nothing to optimize. + if let TerminatorKind::Unreachable = body.basic_blocks[START_BLOCK].terminator().kind + && body.basic_blocks[START_BLOCK].statements.is_empty() + { + return body; + } + run_optimization_passes(tcx, &mut body); body -- cgit v1.2.3