diff options
Diffstat (limited to 'compiler/rustc_const_eval/src')
25 files changed, 337 insertions, 405 deletions
diff --git a/compiler/rustc_const_eval/src/check_consts/check.rs b/compiler/rustc_const_eval/src/check_consts/check.rs index 303c490d827..ffe32acb316 100644 --- a/compiler/rustc_const_eval/src/check_consts/check.rs +++ b/compiler/rustc_const_eval/src/check_consts/check.rs @@ -3,6 +3,7 @@ use std::assert_matches::assert_matches; use std::borrow::Cow; use std::mem; +use std::num::NonZero; use std::ops::Deref; use rustc_attr::{ConstStability, StabilityLevel}; @@ -15,12 +16,11 @@ use rustc_middle::mir::visit::Visitor; use rustc_middle::mir::*; use rustc_middle::span_bug; use rustc_middle::ty::adjustment::PointerCoercion; -use rustc_middle::ty::{self, Instance, InstanceKind, Ty, TypeVisitableExt}; +use rustc_middle::ty::{self, Ty, TypeVisitableExt}; use rustc_mir_dataflow::Analysis; use rustc_mir_dataflow::impls::MaybeStorageLive; use rustc_mir_dataflow::storage::always_storage_live_locals; use rustc_span::{Span, Symbol, sym}; -use rustc_trait_selection::error_reporting::InferCtxtErrorExt; use rustc_trait_selection::traits::{ Obligation, ObligationCause, ObligationCauseCode, ObligationCtxt, }; @@ -272,9 +272,18 @@ impl<'mir, 'tcx> Checker<'mir, 'tcx> { /// context. pub fn check_op_spanned<O: NonConstOp<'tcx>>(&mut self, op: O, span: Span) { let gate = match op.status_in_item(self.ccx) { - Status::Unstable { gate, safe_to_expose_on_stable, is_function_call } - if self.tcx.features().enabled(gate) => - { + Status::Unstable { + gate, + safe_to_expose_on_stable, + is_function_call, + gate_already_checked, + } if gate_already_checked || self.tcx.features().enabled(gate) => { + if gate_already_checked { + assert!( + !safe_to_expose_on_stable, + "setting `gate_already_checked` without `safe_to_expose_on_stable` makes no sense" + ); + } // Generally this is allowed since the feature gate is enabled -- except // if this function wants to be safe-to-expose-on-stable. if !safe_to_expose_on_stable @@ -362,31 +371,21 @@ impl<'mir, 'tcx> Checker<'mir, 'tcx> { !is_transient } + /// Returns whether there are const-conditions. fn revalidate_conditional_constness( &mut self, callee: DefId, callee_args: ty::GenericArgsRef<'tcx>, - call_source: CallSource, call_span: Span, - ) { + ) -> bool { let tcx = self.tcx; if !tcx.is_conditionally_const(callee) { - return; + return false; } let const_conditions = tcx.const_conditions(callee).instantiate(tcx, callee_args); - // If there are any const conditions on this fn and `const_trait_impl` - // is not enabled, simply bail. We shouldn't be able to call conditionally - // const functions on stable. - if !const_conditions.is_empty() && !tcx.features().const_trait_impl() { - self.check_op(ops::FnCallNonConst { - callee, - args: callee_args, - span: call_span, - call_source, - feature: Some(sym::const_trait_impl), - }); - return; + if const_conditions.is_empty() { + return false; } let infcx = tcx.infer_ctxt().build(self.body.typing_mode(tcx)); @@ -419,14 +418,11 @@ impl<'mir, 'tcx> Checker<'mir, 'tcx> { let errors = ocx.select_all_or_error(); if !errors.is_empty() { - // FIXME(effects): Soon this should be unconditionally delaying a bug. - if matches!(call_source, CallSource::Normal) && tcx.features().effects() { - tcx.dcx() - .span_delayed_bug(call_span, "this should have reported a ~const error in HIR"); - } else { - infcx.err_ctxt().report_fulfillment_errors(errors); - } + tcx.dcx() + .span_delayed_bug(call_span, "this should have reported a ~const error in HIR"); } + + true } } @@ -633,11 +629,11 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { _ => unreachable!(), }; - let ConstCx { tcx, body, param_env, .. } = *self.ccx; + let ConstCx { tcx, body, .. } = *self.ccx; let fn_ty = func.ty(body, tcx); - let (mut callee, mut fn_args) = match *fn_ty.kind() { + let (callee, fn_args) = match *fn_ty.kind() { ty::FnDef(def_id, fn_args) => (def_id, fn_args), ty::FnPtr(..) => { @@ -651,56 +647,38 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { } }; - self.revalidate_conditional_constness(callee, fn_args, call_source, *fn_span); + let has_const_conditions = + self.revalidate_conditional_constness(callee, fn_args, *fn_span); - let mut is_trait = false; // Attempting to call a trait method? if let Some(trait_did) = tcx.trait_of_item(callee) { - trace!("attempting to call a trait method"); + // We can't determine the actual callee here, so we have to do different checks + // than usual. + trace!("attempting to call a trait method"); let trait_is_const = tcx.is_const_trait(trait_did); - // trait method calls are only permitted when `effects` is enabled. - // typeck ensures the conditions for calling a const trait method are met, - // so we only error if the trait isn't const. We try to resolve the trait - // into the concrete method, and uses that for const stability checks. - // FIXME(effects) we might consider moving const stability checks to typeck as well. - if tcx.features().effects() && trait_is_const { - // This skips the check below that ensures we only call `const fn`. - is_trait = true; - - if let Ok(Some(instance)) = - Instance::try_resolve(tcx, param_env, callee, fn_args) - && let InstanceKind::Item(def) = instance.def - { - // Resolve a trait method call to its concrete implementation, which may be in a - // `const` trait impl. This is only used for the const stability check below, since - // we want to look at the concrete impl's stability. - fn_args = instance.args; - callee = def; - } + + if trait_is_const { + // Trait calls are always conditionally-const. + self.check_op(ops::ConditionallyConstCall { callee, args: fn_args }); + // FIXME(const_trait_impl): do a more fine-grained check whether this + // particular trait can be const-stably called. } else { - // if the trait is const but the user has not enabled the feature(s), - // suggest them. - let feature = if trait_is_const { - Some(if tcx.features().const_trait_impl() { - sym::effects - } else { - sym::const_trait_impl - }) - } else { - None - }; + // Not even a const trait. self.check_op(ops::FnCallNonConst { callee, args: fn_args, span: *fn_span, call_source, - feature, }); - // If we allowed this, we're in miri-unleashed mode, so we might - // as well skip the remaining checks. - return; } + // That's all we can check here. + return; + } + + // Even if we know the callee, ensure we can use conditionally-const calls. + if has_const_conditions { + self.check_op(ops::ConditionallyConstCall { callee, args: fn_args }); } // At this point, we are calling a function, `callee`, whose `DefId` is known... @@ -741,16 +719,27 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { // Intrinsics are language primitives, not regular calls, so treat them separately. if let Some(intrinsic) = tcx.intrinsic(callee) { + if !tcx.is_const_fn(callee) { + // Non-const intrinsic. + self.check_op(ops::IntrinsicNonConst { name: intrinsic.name }); + // If we allowed this, we're in miri-unleashed mode, so we might + // as well skip the remaining checks. + return; + } + // We use `intrinsic.const_stable` to determine if this can be safely exposed to + // stable code, rather than `const_stable_indirect`. This is to make + // `#[rustc_const_stable_indirect]` an attribute that is always safe to add. + // We also ask is_safe_to_expose_on_stable_const_fn; this determines whether the intrinsic + // fallback body is safe to expose on stable. + let is_const_stable = intrinsic.const_stable + || (!intrinsic.must_be_overridden + && is_safe_to_expose_on_stable_const_fn(tcx, callee)); match tcx.lookup_const_stability(callee) { None => { - // Non-const intrinsic. - self.check_op(ops::IntrinsicNonConst { name: intrinsic.name }); - } - Some(ConstStability { feature: None, const_stable_indirect, .. }) => { - // Intrinsic does not need a separate feature gate (we rely on the - // regular stability checker). However, we have to worry about recursive - // const stability. - if !const_stable_indirect && self.enforce_recursive_const_stability() { + // This doesn't need a separate const-stability check -- const-stability equals + // regular stability, and regular stability is checked separately. + // However, we *do* have to worry about *recursive* const stability. + if !is_const_stable && self.enforce_recursive_const_stability() { self.dcx().emit_err(errors::UnmarkedIntrinsicExposed { span: self.span, def_path: self.tcx.def_path_str(callee), @@ -758,33 +747,33 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { } } Some(ConstStability { - feature: Some(feature), level: StabilityLevel::Unstable { .. }, - const_stable_indirect, + feature, .. }) => { self.check_op(ops::IntrinsicUnstable { name: intrinsic.name, feature, - const_stable_indirect, + const_stable_indirect: is_const_stable, }); } Some(ConstStability { level: StabilityLevel::Stable { .. }, .. }) => { - // All good. + // All good. Note that a `#[rustc_const_stable]` intrinsic (meaning it + // can be *directly* invoked from stable const code) does not always + // have the `#[rustc_const_stable_intrinsic]` attribute (which controls + // exposing an intrinsic indirectly); we accept this call anyway. } } // This completes the checks for intrinsics. return; } - // Trait functions are not `const fn` so we have to skip them here. - if !tcx.is_const_fn(callee) && !is_trait { + if !tcx.is_const_fn(callee) { self.check_op(ops::FnCallNonConst { callee, args: fn_args, span: *fn_span, call_source, - feature: None, }); // If we allowed this, we're in miri-unleashed mode, so we might // as well skip the remaining checks. @@ -796,7 +785,7 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { Some(ConstStability { level: StabilityLevel::Stable { .. }, .. }) => { // All good. } - None | Some(ConstStability { feature: None, .. }) => { + None => { // This doesn't need a separate const-stability check -- const-stability equals // regular stability, and regular stability is checked separately. // However, we *do* have to worry about *recursive* const stability. @@ -810,8 +799,8 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { } } Some(ConstStability { - feature: Some(feature), - level: StabilityLevel::Unstable { implied_by: implied_feature, .. }, + level: StabilityLevel::Unstable { implied_by: implied_feature, issue, .. }, + feature, .. }) => { // An unstable const fn with a feature gate. @@ -820,6 +809,12 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { // We only honor `span.allows_unstable` aka `#[allow_internal_unstable]` if // the callee is safe to expose, to avoid bypassing recursive stability. + // This is not ideal since it means the user sees an error, not the macro + // author, but that's also the case if one forgets to set + // `#[allow_internal_unstable]` in the first place. Note that this cannot be + // integrated in the check below since we want to enforce + // `callee_safe_to_expose_on_stable` even if + // `!self.enforce_recursive_const_stability()`. if (self.span.allows_unstable(feature) || implied_feature.is_some_and(|f| self.span.allows_unstable(f))) && callee_safe_to_expose_on_stable @@ -833,16 +828,30 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { // to allow this. let feature_enabled = callee.is_local() || tcx.features().enabled(feature) - || implied_feature.is_some_and(|f| tcx.features().enabled(f)); - // We do *not* honor this if we are in the "danger zone": we have to enforce - // recursive const-stability and the callee is not safe-to-expose. In that - // case we need `check_op` to do the check. - let danger_zone = !callee_safe_to_expose_on_stable - && self.enforce_recursive_const_stability(); - if danger_zone || !feature_enabled { + || implied_feature.is_some_and(|f| tcx.features().enabled(f)) + || { + // When we're compiling the compiler itself we may pull in + // crates from crates.io, but those crates may depend on other + // crates also pulled in from crates.io. We want to ideally be + // able to compile everything without requiring upstream + // modifications, so in the case that this looks like a + // `rustc_private` crate (e.g., a compiler crate) and we also have + // the `-Z force-unstable-if-unmarked` flag present (we're + // compiling a compiler crate), then let this missing feature + // annotation slide. + // This matches what we do in `eval_stability_allow_unstable` for + // regular stability. + feature == sym::rustc_private + && issue == NonZero::new(27812) + && self.tcx.sess.opts.unstable_opts.force_unstable_if_unmarked + }; + // Even if the feature is enabled, we still need check_op to double-check + // this if the callee is not safe to expose on stable. + if !feature_enabled || !callee_safe_to_expose_on_stable { self.check_op(ops::FnCallUnstable { def_id: callee, feature, + feature_enabled, safe_to_expose_on_stable: callee_safe_to_expose_on_stable, }); } diff --git a/compiler/rustc_const_eval/src/check_consts/mod.rs b/compiler/rustc_const_eval/src/check_consts/mod.rs index dcdaafaecc2..ebdd55a4f70 100644 --- a/compiler/rustc_const_eval/src/check_consts/mod.rs +++ b/compiler/rustc_const_eval/src/check_consts/mod.rs @@ -53,10 +53,11 @@ impl<'mir, 'tcx> ConstCx<'mir, 'tcx> { } pub fn enforce_recursive_const_stability(&self) -> bool { - // We can skip this if `staged_api` is not enabled, since in such crates - // `lookup_const_stability` will always be `None`. + // We can skip this if neither `staged_api` nor `-Zforce-unstable-if-unmarked` are enabled, + // since in such crates `lookup_const_stability` will always be `None`. self.const_kind == Some(hir::ConstContext::ConstFn) - && self.tcx.features().staged_api() + && (self.tcx.features().staged_api() + || self.tcx.sess.opts.unstable_opts.force_unstable_if_unmarked) && is_safe_to_expose_on_stable_const_fn(self.tcx, self.def_id().to_def_id()) } @@ -109,14 +110,15 @@ pub fn is_safe_to_expose_on_stable_const_fn(tcx: TyCtxt<'_>, def_id: DefId) -> b match tcx.lookup_const_stability(def_id) { None => { - // Only marked functions can be trusted. Note that this may be a function in a - // non-staged-API crate where no recursive checks were done! - false + // In a `staged_api` crate, we do enforce recursive const stability for all unmarked + // functions, so we can trust local functions. But in another crate we don't know which + // rules were applied, so we can't trust that. + def_id.is_local() && tcx.features().staged_api() } Some(stab) => { - // We consider things safe-to-expose if they are stable, if they don't have any explicit - // const stability attribute, or if they are marked as `const_stable_indirect`. - stab.is_const_stable() || stab.feature.is_none() || stab.const_stable_indirect + // We consider things safe-to-expose if they are stable or if they are marked as + // `const_stable_indirect`. + stab.is_const_stable() || stab.const_stable_indirect } } } diff --git a/compiler/rustc_const_eval/src/check_consts/ops.rs b/compiler/rustc_const_eval/src/check_consts/ops.rs index ce36701a942..ca95e42dd2b 100644 --- a/compiler/rustc_const_eval/src/check_consts/ops.rs +++ b/compiler/rustc_const_eval/src/check_consts/ops.rs @@ -28,6 +28,9 @@ pub enum Status { Unstable { /// The feature that must be enabled to use this operation. gate: Symbol, + /// Whether the feature gate was already checked (because the logic is a bit more + /// complicated than just checking a single gate). + gate_already_checked: bool, /// Whether it is allowed to use this operation from stable `const fn`. /// This will usually be `false`. safe_to_expose_on_stable: bool, @@ -70,6 +73,38 @@ impl<'tcx> NonConstOp<'tcx> for FnCallIndirect { } } +/// A call to a function that is in a trait, or has trait bounds that make it conditionally-const. +#[derive(Debug)] +pub(crate) struct ConditionallyConstCall<'tcx> { + pub callee: DefId, + pub args: GenericArgsRef<'tcx>, +} + +impl<'tcx> NonConstOp<'tcx> for ConditionallyConstCall<'tcx> { + fn status_in_item(&self, _ccx: &ConstCx<'_, 'tcx>) -> Status { + // We use the `const_trait_impl` gate for all conditionally-const calls. + Status::Unstable { + gate: sym::const_trait_impl, + gate_already_checked: false, + safe_to_expose_on_stable: false, + // We don't want the "mark the callee as `#[rustc_const_stable_indirect]`" hint + is_function_call: false, + } + } + + fn build_error(&self, ccx: &ConstCx<'_, 'tcx>, span: Span) -> Diag<'tcx> { + ccx.tcx.sess.create_feature_err( + errors::ConditionallyConstCall { + span, + def_path_str: ccx.tcx.def_path_str_with_args(self.callee, self.args), + def_descr: ccx.tcx.def_descr(self.callee), + kind: ccx.const_kind(), + }, + sym::const_trait_impl, + ) + } +} + /// A function call where the callee is not marked as `const`. #[derive(Debug, Clone, Copy)] pub(crate) struct FnCallNonConst<'tcx> { @@ -77,7 +112,6 @@ pub(crate) struct FnCallNonConst<'tcx> { pub args: GenericArgsRef<'tcx>, pub span: Span, pub call_source: CallSource, - pub feature: Option<Symbol>, } impl<'tcx> NonConstOp<'tcx> for FnCallNonConst<'tcx> { @@ -85,7 +119,7 @@ impl<'tcx> NonConstOp<'tcx> for FnCallNonConst<'tcx> { #[allow(rustc::diagnostic_outside_of_impl)] #[allow(rustc::untranslatable_diagnostic)] fn build_error(&self, ccx: &ConstCx<'_, 'tcx>, _: Span) -> Diag<'tcx> { - let FnCallNonConst { callee, args, span, call_source, feature } = *self; + let FnCallNonConst { callee, args, span, call_source } = *self; let ConstCx { tcx, param_env, .. } = *ccx; let caller = ccx.def_id(); @@ -120,7 +154,7 @@ impl<'tcx> NonConstOp<'tcx> for FnCallNonConst<'tcx> { let implsrc = selcx.select(&obligation); if let Ok(Some(ImplSource::UserDefined(data))) = implsrc { - // FIXME(effects) revisit this + // FIXME(const_trait_impl) revisit this if !tcx.is_const_trait_impl(data.impl_def_id) { let span = tcx.def_span(data.impl_def_id); err.subdiagnostic(errors::NonConstImplNote { span }); @@ -285,14 +319,6 @@ impl<'tcx> NonConstOp<'tcx> for FnCallNonConst<'tcx> { ccx.const_kind(), )); - if let Some(feature) = feature { - ccx.tcx.disabled_nightly_features( - &mut err, - Some(ccx.tcx.local_def_id_to_hir_id(caller)), - [(String::new(), feature)], - ); - } - if let ConstContext::Static(_) = ccx.const_kind() { err.note(fluent_generated::const_eval_lazy_lock); } @@ -308,6 +334,9 @@ impl<'tcx> NonConstOp<'tcx> for FnCallNonConst<'tcx> { pub(crate) struct FnCallUnstable { pub def_id: DefId, pub feature: Symbol, + /// If this is true, then the feature is enabled, but we need to still check if it is safe to + /// expose on stable. + pub feature_enabled: bool, pub safe_to_expose_on_stable: bool, } @@ -315,12 +344,14 @@ impl<'tcx> NonConstOp<'tcx> for FnCallUnstable { fn status_in_item(&self, _ccx: &ConstCx<'_, 'tcx>) -> Status { Status::Unstable { gate: self.feature, + gate_already_checked: self.feature_enabled, safe_to_expose_on_stable: self.safe_to_expose_on_stable, is_function_call: true, } } fn build_error(&self, ccx: &ConstCx<'_, 'tcx>, span: Span) -> Diag<'tcx> { + assert!(!self.feature_enabled); let mut err = ccx.dcx().create_err(errors::UnstableConstFn { span, def_path: ccx.tcx.def_path_str(self.def_id), @@ -361,6 +392,7 @@ impl<'tcx> NonConstOp<'tcx> for IntrinsicUnstable { fn status_in_item(&self, _ccx: &ConstCx<'_, 'tcx>) -> Status { Status::Unstable { gate: self.feature, + gate_already_checked: false, safe_to_expose_on_stable: self.const_stable_indirect, // We do *not* want to suggest to mark the intrinsic as `const_stable_indirect`, // that's not a trivial change! @@ -388,6 +420,7 @@ impl<'tcx> NonConstOp<'tcx> for Coroutine { { Status::Unstable { gate: sym::const_async_blocks, + gate_already_checked: false, safe_to_expose_on_stable: false, is_function_call: false, } @@ -398,15 +431,8 @@ impl<'tcx> NonConstOp<'tcx> for Coroutine { fn build_error(&self, ccx: &ConstCx<'_, 'tcx>, span: Span) -> Diag<'tcx> { let msg = format!("{:#}s are not allowed in {}s", self.0, ccx.const_kind()); - if let hir::CoroutineKind::Desugared( - hir::CoroutineDesugaring::Async, - hir::CoroutineSource::Block, - ) = self.0 - { - ccx.tcx.sess.create_feature_err( - errors::UnallowedOpInConstContext { span, msg }, - sym::const_async_blocks, - ) + if let Status::Unstable { gate, .. } = self.status_in_item(ccx) { + ccx.tcx.sess.create_feature_err(errors::UnallowedOpInConstContext { span, msg }, gate) } else { ccx.dcx().create_err(errors::UnallowedOpInConstContext { span, msg }) } diff --git a/compiler/rustc_const_eval/src/check_consts/qualifs.rs b/compiler/rustc_const_eval/src/check_consts/qualifs.rs index e8637ba45cf..29a08579175 100644 --- a/compiler/rustc_const_eval/src/check_consts/qualifs.rs +++ b/compiler/rustc_const_eval/src/check_consts/qualifs.rs @@ -192,7 +192,7 @@ impl Qualif for NeedsNonConstDrop { return false; } - // FIXME(effects): Reimplement const drop checking. + // FIXME(const_trait_impl): Reimplement const drop checking. NeedsDrop::in_any_value_of_ty(cx, ty) } diff --git a/compiler/rustc_const_eval/src/const_eval/dummy_machine.rs b/compiler/rustc_const_eval/src/const_eval/dummy_machine.rs index bc2661c4fc7..e49d702127d 100644 --- a/compiler/rustc_const_eval/src/const_eval/dummy_machine.rs +++ b/compiler/rustc_const_eval/src/const_eval/dummy_machine.rs @@ -86,7 +86,7 @@ impl<'tcx> interpret::Machine<'tcx> for DummyMachine { fn find_mir_or_eval_fn( _ecx: &mut InterpCx<'tcx, Self>, _instance: ty::Instance<'tcx>, - _abi: rustc_target::spec::abi::Abi, + _abi: rustc_abi::ExternAbi, _args: &[interpret::FnArg<'tcx, Self::Provenance>], _destination: &interpret::MPlaceTy<'tcx, Self::Provenance>, _target: Option<BasicBlock>, diff --git a/compiler/rustc_const_eval/src/const_eval/eval_queries.rs b/compiler/rustc_const_eval/src/const_eval/eval_queries.rs index 81b9d73b952..a430d9dc797 100644 --- a/compiler/rustc_const_eval/src/const_eval/eval_queries.rs +++ b/compiler/rustc_const_eval/src/const_eval/eval_queries.rs @@ -472,8 +472,9 @@ fn report_validation_error<'tcx>( backtrace.print_backtrace(); let bytes = ecx.print_alloc_bytes_for_diagnostics(alloc_id); - let (size, align, _) = ecx.get_alloc_info(alloc_id); - let raw_bytes = errors::RawBytesNote { size: size.bytes(), align: align.bytes(), bytes }; + let info = ecx.get_alloc_info(alloc_id); + let raw_bytes = + errors::RawBytesNote { size: info.size.bytes(), align: info.align.bytes(), bytes }; crate::const_eval::report( *ecx.tcx, diff --git a/compiler/rustc_const_eval/src/const_eval/fn_queries.rs b/compiler/rustc_const_eval/src/const_eval/fn_queries.rs index 037fdcbcf9b..beff0cd99fc 100644 --- a/compiler/rustc_const_eval/src/const_eval/fn_queries.rs +++ b/compiler/rustc_const_eval/src/const_eval/fn_queries.rs @@ -25,15 +25,9 @@ fn constness(tcx: TyCtxt<'_>, def_id: LocalDefId) -> hir::Constness { hir::Constness::Const } hir::Node::Item(hir::Item { kind: hir::ItemKind::Impl(impl_), .. }) => impl_.constness, - hir::Node::ForeignItem(hir::ForeignItem { kind: hir::ForeignItemKind::Fn(..), .. }) => { - // Intrinsics use `rustc_const_{un,}stable` attributes to indicate constness. All other - // foreign items cannot be evaluated at compile-time. - let is_const = if tcx.intrinsic(def_id).is_some() { - tcx.lookup_const_stability(def_id).is_some() - } else { - false - }; - if is_const { hir::Constness::Const } else { hir::Constness::NotConst } + hir::Node::ForeignItem(_) => { + // Foreign items cannot be evaluated at compile-time. + hir::Constness::NotConst } hir::Node::Expr(e) if let hir::ExprKind::Closure(c) = e.kind => c.constness, _ => { diff --git a/compiler/rustc_const_eval/src/const_eval/machine.rs b/compiler/rustc_const_eval/src/const_eval/machine.rs index 5f0bc8539ee..f12320cb851 100644 --- a/compiler/rustc_const_eval/src/const_eval/machine.rs +++ b/compiler/rustc_const_eval/src/const_eval/machine.rs @@ -1,21 +1,19 @@ use std::borrow::{Borrow, Cow}; use std::fmt; use std::hash::Hash; -use std::ops::ControlFlow; +use rustc_abi::{Align, ExternAbi, Size}; use rustc_ast::Mutability; use rustc_data_structures::fx::{FxHashMap, FxIndexMap, IndexEntry}; use rustc_hir::def_id::{DefId, LocalDefId}; use rustc_hir::{self as hir, CRATE_HIR_ID, LangItem}; use rustc_middle::mir::AssertMessage; use rustc_middle::query::TyCtxtAt; -use rustc_middle::ty::layout::{FnAbiOf, TyAndLayout}; +use rustc_middle::ty::layout::TyAndLayout; use rustc_middle::ty::{self, Ty, TyCtxt}; use rustc_middle::{bug, mir}; use rustc_span::Span; use rustc_span::symbol::{Symbol, sym}; -use rustc_target::abi::{Align, Size}; -use rustc_target::spec::abi::Abi as CallAbi; use tracing::debug; use super::error::*; @@ -23,9 +21,9 @@ use crate::errors::{LongRunning, LongRunningWarn}; use crate::fluent_generated as fluent; use crate::interpret::{ self, AllocId, AllocRange, ConstAllocation, CtfeProvenance, FnArg, Frame, GlobalAlloc, ImmTy, - InterpCx, InterpResult, MPlaceTy, OpTy, Pointer, PointerArithmetic, RangeSet, Scalar, - StackPopCleanup, compile_time_machine, interp_ok, throw_exhaust, throw_inval, throw_ub, - throw_ub_custom, throw_unsup, throw_unsup_format, + InterpCx, InterpResult, MPlaceTy, OpTy, Pointer, RangeSet, Scalar, compile_time_machine, + interp_ok, throw_exhaust, throw_inval, throw_ub, throw_ub_custom, throw_unsup, + throw_unsup_format, }; /// When hitting this many interpreted terminators we emit a deny by default lint @@ -227,8 +225,8 @@ impl<'tcx> CompileTimeInterpCx<'tcx> { &mut self, instance: ty::Instance<'tcx>, args: &[FnArg<'tcx>], - dest: &MPlaceTy<'tcx>, - ret: Option<mir::BasicBlock>, + _dest: &MPlaceTy<'tcx>, + _ret: Option<mir::BasicBlock>, ) -> InterpResult<'tcx, Option<ty::Instance<'tcx>>> { let def_id = instance.def_id(); @@ -260,86 +258,17 @@ impl<'tcx> CompileTimeInterpCx<'tcx> { ); return interp_ok(Some(new_instance)); - } else if self.tcx.is_lang_item(def_id, LangItem::AlignOffset) { - let args = self.copy_fn_args(args); - // For align_offset, we replace the function call if the pointer has no address. - match self.align_offset(instance, &args, dest, ret)? { - ControlFlow::Continue(()) => return interp_ok(Some(instance)), - ControlFlow::Break(()) => return interp_ok(None), - } } interp_ok(Some(instance)) } - /// `align_offset(ptr, target_align)` needs special handling in const eval, because the pointer - /// may not have an address. - /// - /// If `ptr` does have a known address, then we return `Continue(())` and the function call should - /// proceed as normal. - /// - /// If `ptr` doesn't have an address, but its underlying allocation's alignment is at most - /// `target_align`, then we call the function again with an dummy address relative to the - /// allocation. - /// - /// If `ptr` doesn't have an address and `target_align` is stricter than the underlying - /// allocation's alignment, then we return `usize::MAX` immediately. - fn align_offset( - &mut self, - instance: ty::Instance<'tcx>, - args: &[OpTy<'tcx>], - dest: &MPlaceTy<'tcx>, - ret: Option<mir::BasicBlock>, - ) -> InterpResult<'tcx, ControlFlow<()>> { - assert_eq!(args.len(), 2); - - let ptr = self.read_pointer(&args[0])?; - let target_align = self.read_scalar(&args[1])?.to_target_usize(self)?; - - if !target_align.is_power_of_two() { - throw_ub_custom!( - fluent::const_eval_align_offset_invalid_align, - target_align = target_align, - ); - } - - match self.ptr_try_get_alloc_id(ptr, 0) { - Ok((alloc_id, offset, _extra)) => { - let (_size, alloc_align, _kind) = self.get_alloc_info(alloc_id); - - if target_align <= alloc_align.bytes() { - // Extract the address relative to the allocation base that is definitely - // sufficiently aligned and call `align_offset` again. - let addr = ImmTy::from_uint(offset.bytes(), args[0].layout).into(); - let align = ImmTy::from_uint(target_align, args[1].layout).into(); - let fn_abi = self.fn_abi_of_instance(instance, ty::List::empty())?; - - // Push the stack frame with our own adjusted arguments. - self.init_stack_frame( - instance, - self.load_mir(instance.def, None)?, - fn_abi, - &[FnArg::Copy(addr), FnArg::Copy(align)], - /* with_caller_location = */ false, - dest, - StackPopCleanup::Goto { ret, unwind: mir::UnwindAction::Unreachable }, - )?; - interp_ok(ControlFlow::Break(())) - } else { - // Not alignable in const, return `usize::MAX`. - let usize_max = Scalar::from_target_usize(self.target_usize_max(), self); - self.write_scalar(usize_max, dest)?; - self.return_to_block(ret)?; - interp_ok(ControlFlow::Break(())) - } - } - Err(_addr) => { - // The pointer has an address, continue with function call. - interp_ok(ControlFlow::Continue(())) - } - } - } - /// See documentation on the `ptr_guaranteed_cmp` intrinsic. + /// Returns `2` if the result is unknown. + /// Returns `1` if the pointers are guaranteed equal. + /// Returns `0` if the pointers are guaranteed inequal. + /// + /// Note that this intrinsic is exposed on stable for comparison with null. In other words, any + /// change to this function that affects comparison with null is insta-stable! fn guaranteed_cmp(&mut self, a: Scalar, b: Scalar) -> InterpResult<'tcx, u8> { interp_ok(match (a, b) { // Comparisons between integers are always known. @@ -411,7 +340,7 @@ impl<'tcx> interpret::Machine<'tcx> for CompileTimeMachine<'tcx> { fn find_mir_or_eval_fn( ecx: &mut InterpCx<'tcx, Self>, orig_instance: ty::Instance<'tcx>, - _abi: CallAbi, + _abi: ExternAbi, args: &[FnArg<'tcx>], dest: &MPlaceTy<'tcx>, ret: Option<mir::BasicBlock>, @@ -431,7 +360,7 @@ impl<'tcx> interpret::Machine<'tcx> for CompileTimeMachine<'tcx> { // sensitive check here. But we can at least rule out functions that are not const at // all. That said, we have to allow calling functions inside a trait marked with // #[const_trait]. These *are* const-checked! - // FIXME(effects): why does `is_const_fn` not classify them as const? + // FIXME(const_trait_impl): why does `is_const_fn` not classify them as const? if (!ecx.tcx.is_const_fn(def) && !ecx.tcx.is_const_default_method(def)) || ecx.tcx.has_attr(def, sym::rustc_do_not_const_check) { diff --git a/compiler/rustc_const_eval/src/const_eval/mod.rs b/compiler/rustc_const_eval/src/const_eval/mod.rs index e2e4754a45c..d5012236c34 100644 --- a/compiler/rustc_const_eval/src/const_eval/mod.rs +++ b/compiler/rustc_const_eval/src/const_eval/mod.rs @@ -1,9 +1,9 @@ // Not in interpret to make sure we do not use private implementation details +use rustc_abi::VariantIdx; use rustc_middle::query::{Key, TyCtxtAt}; use rustc_middle::ty::{self, Ty, TyCtxt}; use rustc_middle::{bug, mir}; -use rustc_target::abi::VariantIdx; use tracing::instrument; use crate::interpret::InterpCx; diff --git a/compiler/rustc_const_eval/src/errors.rs b/compiler/rustc_const_eval/src/errors.rs index 38b87b72634..604e5ed61a3 100644 --- a/compiler/rustc_const_eval/src/errors.rs +++ b/compiler/rustc_const_eval/src/errors.rs @@ -2,6 +2,7 @@ use std::borrow::Cow; use std::fmt::Write; use either::Either; +use rustc_abi::WrappingRange; use rustc_errors::codes::*; use rustc_errors::{ Diag, DiagArgValue, DiagCtxtHandle, DiagMessage, Diagnostic, EmissionGuarantee, Level, @@ -15,8 +16,7 @@ use rustc_middle::mir::interpret::{ }; use rustc_middle::ty::{self, Mutability, Ty}; use rustc_span::{Span, Symbol}; -use rustc_target::abi::WrappingRange; -use rustc_target::abi::call::AdjustForForeignAbiError; +use rustc_target::callconv::AdjustForForeignAbiError; use crate::interpret::InternKind; @@ -177,6 +177,16 @@ pub(crate) struct NonConstFmtMacroCall { } #[derive(Diagnostic)] +#[diag(const_eval_conditionally_const_call)] +pub(crate) struct ConditionallyConstCall { + #[primary_span] + pub span: Span, + pub def_path_str: String, + pub def_descr: &'static str, + pub kind: ConstContext, +} + +#[derive(Diagnostic)] #[diag(const_eval_non_const_fn_call, code = E0015)] pub(crate) struct NonConstFnCall { #[primary_span] diff --git a/compiler/rustc_const_eval/src/interpret/call.rs b/compiler/rustc_const_eval/src/interpret/call.rs index 1915bf75c95..ef0902e4226 100644 --- a/compiler/rustc_const_eval/src/interpret/call.rs +++ b/compiler/rustc_const_eval/src/interpret/call.rs @@ -4,13 +4,12 @@ use std::assert_matches::assert_matches; use std::borrow::Cow; use either::{Left, Right}; +use rustc_abi::{self as abi, ExternAbi, FieldIdx, Integer, VariantIdx}; use rustc_middle::ty::layout::{FnAbiOf, IntegerExt, LayoutOf, TyAndLayout}; -use rustc_middle::ty::{self, AdtDef, Instance, Ty}; +use rustc_middle::ty::{self, AdtDef, Instance, Ty, VariantDef}; use rustc_middle::{bug, mir, span_bug}; use rustc_span::sym; -use rustc_target::abi::call::{ArgAbi, FnAbi, PassMode}; -use rustc_target::abi::{self, FieldIdx, Integer}; -use rustc_target::spec::abi::Abi; +use rustc_target::callconv::{ArgAbi, FnAbi, PassMode}; use tracing::{info, instrument, trace}; use super::{ @@ -93,29 +92,46 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { /// Unwrap types that are guaranteed a null-pointer-optimization fn unfold_npo(&self, layout: TyAndLayout<'tcx>) -> InterpResult<'tcx, TyAndLayout<'tcx>> { - // Check if this is `Option` wrapping some type or if this is `Result` wrapping a 1-ZST and - // another type. + // Check if this is an option-like type wrapping some type. let ty::Adt(def, args) = layout.ty.kind() else { // Not an ADT, so definitely no NPO. return interp_ok(layout); }; - let inner = if self.tcx.is_diagnostic_item(sym::Option, def.did()) { - // The wrapped type is the only arg. - self.layout_of(args[0].as_type().unwrap())? - } else if self.tcx.is_diagnostic_item(sym::Result, def.did()) { - // We want to extract which (if any) of the args is not a 1-ZST. - let lhs = self.layout_of(args[0].as_type().unwrap())?; - let rhs = self.layout_of(args[1].as_type().unwrap())?; - if lhs.is_1zst() { - rhs - } else if rhs.is_1zst() { - lhs - } else { - return interp_ok(layout); // no NPO + if def.variants().len() != 2 { + // Not a 2-variant enum, so no NPO. + return interp_ok(layout); + } + assert!(def.is_enum()); + + let all_fields_1zst = |variant: &VariantDef| -> InterpResult<'tcx, _> { + for field in &variant.fields { + let ty = field.ty(*self.tcx, args); + let layout = self.layout_of(ty)?; + if !layout.is_1zst() { + return interp_ok(false); + } } + interp_ok(true) + }; + + // If one variant consists entirely of 1-ZST, then the other variant + // is the only "relevant" one for this check. + let var0 = VariantIdx::from_u32(0); + let var1 = VariantIdx::from_u32(1); + let relevant_variant = if all_fields_1zst(def.variant(var0))? { + def.variant(var1) + } else if all_fields_1zst(def.variant(var1))? { + def.variant(var0) } else { - return interp_ok(layout); // no NPO + // No varant is all-1-ZST, so no NPO. + return interp_ok(layout); }; + // The "relevant" variant must have exactly one field, and its type is the "inner" type. + if relevant_variant.fields.len() != 1 { + return interp_ok(layout); + } + let inner = relevant_variant.fields[FieldIdx::from_u32(0)].ty(*self.tcx, args); + let inner = self.layout_of(inner)?; // Check if the inner type is one of the NPO-guaranteed ones. // For that we first unpeel transparent *structs* (but not unions). @@ -488,7 +504,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { pub(super) fn init_fn_call( &mut self, fn_val: FnVal<'tcx, M::ExtraFnVal>, - (caller_abi, caller_fn_abi): (Abi, &FnAbi<'tcx, Ty<'tcx>>), + (caller_abi, caller_fn_abi): (ExternAbi, &FnAbi<'tcx, Ty<'tcx>>), args: &[FnArg<'tcx, M::Provenance>], with_caller_location: bool, destination: &MPlaceTy<'tcx, M::Provenance>, @@ -566,7 +582,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { // Special handling for the closure ABI: untuple the last argument. let args: Cow<'_, [FnArg<'tcx, M::Provenance>]> = - if caller_abi == Abi::RustCall && !args.is_empty() { + if caller_abi == ExternAbi::RustCall && !args.is_empty() { // Untuple let (untuple_arg, args) = args.split_last().unwrap(); trace!("init_fn_call: Will pass last argument by untupling"); @@ -732,7 +748,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { pub(super) fn init_fn_tail_call( &mut self, fn_val: FnVal<'tcx, M::ExtraFnVal>, - (caller_abi, caller_fn_abi): (Abi, &FnAbi<'tcx, Ty<'tcx>>), + (caller_abi, caller_fn_abi): (ExternAbi, &FnAbi<'tcx, Ty<'tcx>>), args: &[FnArg<'tcx, M::Provenance>], with_caller_location: bool, ) -> InterpResult<'tcx> { @@ -817,7 +833,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { self.init_fn_call( FnVal::Instance(instance), - (Abi::Rust, fn_abi), + (ExternAbi::Rust, fn_abi), &[FnArg::Copy(arg.into())], false, &ret, diff --git a/compiler/rustc_const_eval/src/interpret/cast.rs b/compiler/rustc_const_eval/src/interpret/cast.rs index 60d5e904bd9..49559059265 100644 --- a/compiler/rustc_const_eval/src/interpret/cast.rs +++ b/compiler/rustc_const_eval/src/interpret/cast.rs @@ -1,5 +1,6 @@ use std::assert_matches::assert_matches; +use rustc_abi::Integer; use rustc_apfloat::ieee::{Double, Half, Quad, Single}; use rustc_apfloat::{Float, FloatConvert}; use rustc_middle::mir::CastKind; @@ -8,7 +9,6 @@ use rustc_middle::ty::adjustment::PointerCoercion; use rustc_middle::ty::layout::{IntegerExt, LayoutOf, TyAndLayout}; use rustc_middle::ty::{self, FloatTy, Ty}; use rustc_middle::{bug, span_bug}; -use rustc_target::abi::Integer; use rustc_type_ir::TyKind::*; use tracing::trace; diff --git a/compiler/rustc_const_eval/src/interpret/discriminant.rs b/compiler/rustc_const_eval/src/interpret/discriminant.rs index bb4ac9556ea..f94d0cbb42b 100644 --- a/compiler/rustc_const_eval/src/interpret/discriminant.rs +++ b/compiler/rustc_const_eval/src/interpret/discriminant.rs @@ -1,9 +1,9 @@ //! Functions for reading and writing discriminants of multi-variant layouts (enums and coroutines). +use rustc_abi::{self as abi, TagEncoding, VariantIdx, Variants}; use rustc_middle::ty::layout::{LayoutOf, PrimitiveExt}; use rustc_middle::ty::{self, CoroutineArgsExt, ScalarInt, Ty}; use rustc_middle::{mir, span_bug}; -use rustc_target::abi::{self, TagEncoding, VariantIdx, Variants}; use tracing::{instrument, trace}; use super::{ diff --git a/compiler/rustc_const_eval/src/interpret/eval_context.rs b/compiler/rustc_const_eval/src/interpret/eval_context.rs index 9043bd3e28e..ff6d5b28b3b 100644 --- a/compiler/rustc_const_eval/src/interpret/eval_context.rs +++ b/compiler/rustc_const_eval/src/interpret/eval_context.rs @@ -1,4 +1,5 @@ use either::{Left, Right}; +use rustc_abi::{Align, HasDataLayout, Size, TargetDataLayout}; use rustc_errors::DiagCtxtHandle; use rustc_hir::def_id::DefId; use rustc_infer::infer::TyCtxtInferExt; @@ -15,8 +16,7 @@ use rustc_middle::ty::{ use rustc_middle::{mir, span_bug}; use rustc_session::Limit; use rustc_span::Span; -use rustc_target::abi::call::FnAbi; -use rustc_target::abi::{Align, HasDataLayout, Size, TargetDataLayout}; +use rustc_target::callconv::FnAbi; use rustc_trait_selection::traits::ObligationCtxt; use tracing::{debug, instrument, trace}; diff --git a/compiler/rustc_const_eval/src/interpret/intrinsics.rs b/compiler/rustc_const_eval/src/interpret/intrinsics.rs index 80e14ee887c..d89d73824aa 100644 --- a/compiler/rustc_const_eval/src/interpret/intrinsics.rs +++ b/compiler/rustc_const_eval/src/interpret/intrinsics.rs @@ -4,6 +4,7 @@ use std::assert_matches::assert_matches; +use rustc_abi::Size; use rustc_apfloat::ieee::{Double, Half, Quad, Single}; use rustc_hir::def_id::DefId; use rustc_middle::mir::{self, BinOp, ConstValue, NonDivergingIntrinsic}; @@ -11,7 +12,6 @@ use rustc_middle::ty::layout::{LayoutOf as _, TyAndLayout, ValidityRequirement}; use rustc_middle::ty::{GenericArgsRef, Ty, TyCtxt}; use rustc_middle::{bug, ty}; use rustc_span::symbol::{Symbol, sym}; -use rustc_target::abi::Size; use tracing::trace; use super::memory::MemoryKind; @@ -417,6 +417,9 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { // These just return their argument self.copy_op(&args[0], dest)?; } + sym::cold_path => { + // This is a no-op. The intrinsic is just a hint to the optimizer. + } sym::raw_eq => { let result = self.raw_eq_intrinsic(&args[0], &args[1])?; self.write_scalar(result, dest)?; diff --git a/compiler/rustc_const_eval/src/interpret/machine.rs b/compiler/rustc_const_eval/src/interpret/machine.rs index 89d49ba046e..dbe09d55b2d 100644 --- a/compiler/rustc_const_eval/src/interpret/machine.rs +++ b/compiler/rustc_const_eval/src/interpret/machine.rs @@ -6,6 +6,7 @@ use std::borrow::{Borrow, Cow}; use std::fmt::Debug; use std::hash::Hash; +use rustc_abi::{Align, ExternAbi, Size}; use rustc_apfloat::{Float, FloatConvert}; use rustc_ast::{InlineAsmOptions, InlineAsmTemplatePiece}; use rustc_middle::query::TyCtxtAt; @@ -14,8 +15,6 @@ use rustc_middle::ty::layout::TyAndLayout; use rustc_middle::{mir, ty}; use rustc_span::Span; use rustc_span::def_id::DefId; -use rustc_target::abi::{Align, Size}; -use rustc_target::spec::abi::Abi as CallAbi; use super::{ AllocBytes, AllocId, AllocKind, AllocRange, Allocation, CTFE_ALLOC_SALT, ConstAllocation, @@ -202,7 +201,7 @@ pub trait Machine<'tcx>: Sized { fn find_mir_or_eval_fn( ecx: &mut InterpCx<'tcx, Self>, instance: ty::Instance<'tcx>, - abi: CallAbi, + abi: ExternAbi, args: &[FnArg<'tcx, Self::Provenance>], destination: &MPlaceTy<'tcx, Self::Provenance>, target: Option<mir::BasicBlock>, @@ -214,7 +213,7 @@ pub trait Machine<'tcx>: Sized { fn call_extra_fn( ecx: &mut InterpCx<'tcx, Self>, fn_val: Self::ExtraFnVal, - abi: CallAbi, + abi: ExternAbi, args: &[FnArg<'tcx, Self::Provenance>], destination: &MPlaceTy<'tcx, Self::Provenance>, target: Option<mir::BasicBlock>, @@ -653,7 +652,7 @@ pub macro compile_time_machine(<$tcx: lifetime>) { fn call_extra_fn( _ecx: &mut InterpCx<$tcx, Self>, fn_val: !, - _abi: CallAbi, + _abi: ExternAbi, _args: &[FnArg<$tcx>], _destination: &MPlaceTy<$tcx, Self::Provenance>, _target: Option<mir::BasicBlock>, diff --git a/compiler/rustc_const_eval/src/interpret/memory.rs b/compiler/rustc_const_eval/src/interpret/memory.rs index 7700eb792ef..09635c96e57 100644 --- a/compiler/rustc_const_eval/src/interpret/memory.rs +++ b/compiler/rustc_const_eval/src/interpret/memory.rs @@ -11,13 +11,12 @@ use std::borrow::{Borrow, Cow}; use std::collections::VecDeque; use std::{fmt, mem, ptr}; +use rustc_abi::{Align, HasDataLayout, Size}; use rustc_ast::Mutability; use rustc_data_structures::fx::{FxHashSet, FxIndexMap}; -use rustc_hir::def::DefKind; use rustc_middle::bug; use rustc_middle::mir::display_allocation; -use rustc_middle::ty::{self, Instance, ParamEnv, Ty, TyCtxt}; -use rustc_target::abi::{Align, HasDataLayout, Size}; +use rustc_middle::ty::{self, Instance, Ty, TyCtxt}; use tracing::{debug, instrument, trace}; use super::{ @@ -72,6 +71,21 @@ pub enum AllocKind { Dead, } +/// Metadata about an `AllocId`. +#[derive(Copy, Clone, PartialEq, Debug)] +pub struct AllocInfo { + pub size: Size, + pub align: Align, + pub kind: AllocKind, + pub mutbl: Mutability, +} + +impl AllocInfo { + fn new(size: Size, align: Align, kind: AllocKind, mutbl: Mutability) -> Self { + Self { size, align, kind, mutbl } + } +} + /// The value of a function pointer. #[derive(Debug, Copy, Clone)] pub enum FnVal<'tcx, Other> { @@ -524,17 +538,22 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { match self.ptr_try_get_alloc_id(ptr, 0) { Err(addr) => is_offset_misaligned(addr, align), Ok((alloc_id, offset, _prov)) => { - let (_size, alloc_align, kind) = self.get_alloc_info(alloc_id); - if let Some(misalign) = - M::alignment_check(self, alloc_id, alloc_align, kind, offset, align) - { + let alloc_info = self.get_alloc_info(alloc_id); + if let Some(misalign) = M::alignment_check( + self, + alloc_id, + alloc_info.align, + alloc_info.kind, + offset, + align, + ) { Some(misalign) } else if M::Provenance::OFFSET_IS_ADDR { is_offset_misaligned(ptr.addr().bytes(), align) } else { // Check allocation alignment and offset alignment. - if alloc_align.bytes() < align.bytes() { - Some(Misalignment { has: alloc_align, required: align }) + if alloc_info.align.bytes() < align.bytes() { + Some(Misalignment { has: alloc_info.align, required: align }) } else { is_offset_misaligned(offset.bytes(), align) } @@ -818,82 +837,45 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { /// Obtain the size and alignment of an allocation, even if that allocation has /// been deallocated. - pub fn get_alloc_info(&self, id: AllocId) -> (Size, Align, AllocKind) { + pub fn get_alloc_info(&self, id: AllocId) -> AllocInfo { // # Regular allocations // Don't use `self.get_raw` here as that will // a) cause cycles in case `id` refers to a static // b) duplicate a global's allocation in miri if let Some((_, alloc)) = self.memory.alloc_map.get(id) { - return (alloc.size(), alloc.align, AllocKind::LiveData); + return AllocInfo::new( + alloc.size(), + alloc.align, + AllocKind::LiveData, + alloc.mutability, + ); } // # Function pointers // (both global from `alloc_map` and local from `extra_fn_ptr_map`) if self.get_fn_alloc(id).is_some() { - return (Size::ZERO, Align::ONE, AllocKind::Function); + return AllocInfo::new(Size::ZERO, Align::ONE, AllocKind::Function, Mutability::Not); } - // # Statics - // Can't do this in the match argument, we may get cycle errors since the lock would - // be held throughout the match. - match self.tcx.try_get_global_alloc(id) { - Some(GlobalAlloc::Static(def_id)) => { - // Thread-local statics do not have a constant address. They *must* be accessed via - // `ThreadLocalRef`; we can never have a pointer to them as a regular constant value. - assert!(!self.tcx.is_thread_local_static(def_id)); - - let DefKind::Static { nested, .. } = self.tcx.def_kind(def_id) else { - bug!("GlobalAlloc::Static is not a static") - }; - - let (size, align) = if nested { - // Nested anonymous statics are untyped, so let's get their - // size and alignment from the allocation itself. This always - // succeeds, as the query is fed at DefId creation time, so no - // evaluation actually occurs. - let alloc = self.tcx.eval_static_initializer(def_id).unwrap(); - (alloc.0.size(), alloc.0.align) - } else { - // Use size and align of the type for everything else. We need - // to do that to - // * avoid cycle errors in case of self-referential statics, - // * be able to get information on extern statics. - let ty = self - .tcx - .type_of(def_id) - .no_bound_vars() - .expect("statics should not have generic parameters"); - let layout = self.tcx.layout_of(ParamEnv::empty().and(ty)).unwrap(); - assert!(layout.is_sized()); - (layout.size, layout.align.abi) - }; - (size, align, AllocKind::LiveData) - } - Some(GlobalAlloc::Memory(alloc)) => { - // Need to duplicate the logic here, because the global allocations have - // different associated types than the interpreter-local ones. - let alloc = alloc.inner(); - (alloc.size(), alloc.align, AllocKind::LiveData) - } - Some(GlobalAlloc::Function { .. }) => { - bug!("We already checked function pointers above") - } - Some(GlobalAlloc::VTable(..)) => { - // No data to be accessed here. But vtables are pointer-aligned. - return (Size::ZERO, self.tcx.data_layout.pointer_align.abi, AllocKind::VTable); - } - // The rest must be dead. - None => { - // Deallocated pointers are allowed, we should be able to find - // them in the map. - let (size, align) = *self - .memory - .dead_alloc_map - .get(&id) - .expect("deallocated pointers should all be recorded in `dead_alloc_map`"); - (size, align, AllocKind::Dead) - } + // # Global allocations + if let Some(global_alloc) = self.tcx.try_get_global_alloc(id) { + let (size, align) = global_alloc.size_and_align(*self.tcx, self.param_env); + let mutbl = global_alloc.mutability(*self.tcx, self.param_env); + let kind = match global_alloc { + GlobalAlloc::Static { .. } | GlobalAlloc::Memory { .. } => AllocKind::LiveData, + GlobalAlloc::Function { .. } => bug!("We already checked function pointers above"), + GlobalAlloc::VTable { .. } => AllocKind::VTable, + }; + return AllocInfo::new(size, align, kind, mutbl); } + + // # Dead pointers + let (size, align) = *self + .memory + .dead_alloc_map + .get(&id) + .expect("deallocated pointers should all be recorded in `dead_alloc_map`"); + AllocInfo::new(size, align, AllocKind::Dead, Mutability::Not) } /// Obtain the size and alignment of a *live* allocation. @@ -902,11 +884,11 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { id: AllocId, msg: CheckInAllocMsg, ) -> InterpResult<'tcx, (Size, Align)> { - let (size, align, kind) = self.get_alloc_info(id); - if matches!(kind, AllocKind::Dead) { + let info = self.get_alloc_info(id); + if matches!(info.kind, AllocKind::Dead) { throw_ub!(PointerUseAfterFree(id, msg)) } - interp_ok((size, align)) + interp_ok((info.size, info.align)) } fn get_fn_alloc(&self, id: AllocId) -> Option<FnVal<'tcx, M::ExtraFnVal>> { @@ -1458,7 +1440,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { let ptr = scalar.to_pointer(self)?; match self.ptr_try_get_alloc_id(ptr, 0) { Ok((alloc_id, offset, _)) => { - let (size, _align, _kind) = self.get_alloc_info(alloc_id); + let size = self.get_alloc_info(alloc_id).size; // If the pointer is out-of-bounds, it may be null. // Note that one-past-the-end (offset == size) is still inbounds, and never null. offset > size diff --git a/compiler/rustc_const_eval/src/interpret/mod.rs b/compiler/rustc_const_eval/src/interpret/mod.rs index 5e84626f77e..f5792aba207 100644 --- a/compiler/rustc_const_eval/src/interpret/mod.rs +++ b/compiler/rustc_const_eval/src/interpret/mod.rs @@ -31,7 +31,7 @@ pub use self::intern::{ }; pub(crate) use self::intrinsics::eval_nullary_intrinsic; pub use self::machine::{AllocMap, Machine, MayLeak, ReturnAction, compile_time_machine}; -pub use self::memory::{AllocKind, AllocRef, AllocRefMut, FnVal, Memory, MemoryKind}; +pub use self::memory::{AllocInfo, AllocKind, AllocRef, AllocRefMut, FnVal, Memory, MemoryKind}; use self::operand::Operand; pub use self::operand::{ImmTy, Immediate, OpTy}; pub use self::place::{MPlaceTy, MemPlaceMeta, PlaceTy, Writeable}; diff --git a/compiler/rustc_const_eval/src/interpret/operator.rs b/compiler/rustc_const_eval/src/interpret/operator.rs index cf280e0c1ae..fbc85d37953 100644 --- a/compiler/rustc_const_eval/src/interpret/operator.rs +++ b/compiler/rustc_const_eval/src/interpret/operator.rs @@ -1,4 +1,5 @@ use either::Either; +use rustc_abi::Size; use rustc_apfloat::{Float, FloatConvert}; use rustc_middle::mir::NullOp; use rustc_middle::mir::interpret::{InterpResult, PointerArithmetic, Scalar}; @@ -6,7 +7,6 @@ use rustc_middle::ty::layout::{LayoutOf, TyAndLayout}; use rustc_middle::ty::{self, FloatTy, ScalarInt, Ty}; use rustc_middle::{bug, mir, span_bug}; use rustc_span::symbol::sym; -use rustc_target::abi::Size; use tracing::trace; use super::{ImmTy, InterpCx, Machine, MemPlaceMeta, interp_ok, throw_ub}; diff --git a/compiler/rustc_const_eval/src/interpret/projection.rs b/compiler/rustc_const_eval/src/interpret/projection.rs index e636090a324..65a93784e2c 100644 --- a/compiler/rustc_const_eval/src/interpret/projection.rs +++ b/compiler/rustc_const_eval/src/interpret/projection.rs @@ -10,10 +10,10 @@ use std::marker::PhantomData; use std::ops::Range; +use rustc_abi::{self as abi, Size, VariantIdx}; use rustc_middle::ty::Ty; use rustc_middle::ty::layout::{LayoutOf, TyAndLayout}; use rustc_middle::{bug, mir, span_bug, ty}; -use rustc_target::abi::{self, Size, VariantIdx}; use tracing::{debug, instrument}; use super::{ diff --git a/compiler/rustc_const_eval/src/interpret/step.rs b/compiler/rustc_const_eval/src/interpret/step.rs index aa752955675..18cff2c5e0f 100644 --- a/compiler/rustc_const_eval/src/interpret/step.rs +++ b/compiler/rustc_const_eval/src/interpret/step.rs @@ -3,13 +3,13 @@ //! The main entry point is the `step` method. use either::Either; +use rustc_abi::{FIRST_VARIANT, FieldIdx}; use rustc_index::IndexSlice; use rustc_middle::ty::layout::FnAbiOf; use rustc_middle::ty::{self, Instance, Ty}; use rustc_middle::{bug, mir, span_bug}; use rustc_span::source_map::Spanned; -use rustc_target::abi::call::FnAbi; -use rustc_target::abi::{FIRST_VARIANT, FieldIdx}; +use rustc_target::callconv::FnAbi; use tracing::{info, instrument, trace}; use super::{ diff --git a/compiler/rustc_const_eval/src/interpret/traits.rs b/compiler/rustc_const_eval/src/interpret/traits.rs index da7d6853c0e..af8d618b6b5 100644 --- a/compiler/rustc_const_eval/src/interpret/traits.rs +++ b/compiler/rustc_const_eval/src/interpret/traits.rs @@ -1,7 +1,7 @@ +use rustc_abi::{Align, Size}; use rustc_middle::mir::interpret::{InterpResult, Pointer}; use rustc_middle::ty::layout::LayoutOf; use rustc_middle::ty::{self, ExistentialPredicateStableCmpExt, Ty, TyCtxt, VtblEntry}; -use rustc_target::abi::{Align, Size}; use tracing::trace; use super::util::ensure_monomorphic_enough; diff --git a/compiler/rustc_const_eval/src/interpret/validity.rs b/compiler/rustc_const_eval/src/interpret/validity.rs index cd2c1ef3613..3a68db9f7f7 100644 --- a/compiler/rustc_const_eval/src/interpret/validity.rs +++ b/compiler/rustc_const_eval/src/interpret/validity.rs @@ -31,8 +31,8 @@ use tracing::trace; use super::machine::AllocMap; use super::{ - AllocId, AllocKind, CheckInAllocMsg, GlobalAlloc, ImmTy, Immediate, InterpCx, InterpResult, - MPlaceTy, Machine, MemPlaceMeta, PlaceTy, Pointer, Projectable, Scalar, ValueVisitor, err_ub, + AllocId, CheckInAllocMsg, GlobalAlloc, ImmTy, Immediate, InterpCx, InterpResult, MPlaceTy, + Machine, MemPlaceMeta, PlaceTy, Pointer, Projectable, Scalar, ValueVisitor, err_ub, format_interp_error, }; @@ -557,9 +557,20 @@ impl<'rt, 'tcx, M: Machine<'tcx>> ValidityVisitor<'rt, 'tcx, M> { if let Ok((alloc_id, _offset, _prov)) = self.ecx.ptr_try_get_alloc_id(place.ptr(), 0) { - if let Some(GlobalAlloc::Static(did)) = - self.ecx.tcx.try_get_global_alloc(alloc_id) - { + // Everything should be already interned. + let Some(global_alloc) = self.ecx.tcx.try_get_global_alloc(alloc_id) else { + assert!(self.ecx.memory.alloc_map.get(alloc_id).is_none()); + // We can't have *any* references to non-existing allocations in const-eval + // as the rest of rustc isn't happy with them... so we throw an error, even + // though for zero-sized references this isn't really UB. + // A potential future alternative would be to resurrect this as a zero-sized allocation + // (which codegen will then compile to an aligned dummy pointer anyway). + throw_validation_failure!(self.path, DanglingPtrUseAfterFree { ptr_kind }); + }; + let (size, _align) = + global_alloc.size_and_align(*self.ecx.tcx, self.ecx.param_env); + + if let GlobalAlloc::Static(did) = global_alloc { let DefKind::Static { nested, .. } = self.ecx.tcx.def_kind(did) else { bug!() }; @@ -593,17 +604,6 @@ impl<'rt, 'tcx, M: Machine<'tcx>> ValidityVisitor<'rt, 'tcx, M> { } } - // Dangling and Mutability check. - let (size, _align, alloc_kind) = self.ecx.get_alloc_info(alloc_id); - if alloc_kind == AllocKind::Dead { - // This can happen for zero-sized references. We can't have *any* references to - // non-existing allocations in const-eval though, interning rejects them all as - // the rest of rustc isn't happy with them... so we throw an error, even though - // this isn't really UB. - // A potential future alternative would be to resurrect this as a zero-sized allocation - // (which codegen will then compile to an aligned dummy pointer anyway). - throw_validation_failure!(self.path, DanglingPtrUseAfterFree { ptr_kind }); - } // If this allocation has size zero, there is no actual mutability here. if size != Size::ZERO { // Determine whether this pointer expects to be pointing to something mutable. @@ -618,7 +618,8 @@ impl<'rt, 'tcx, M: Machine<'tcx>> ValidityVisitor<'rt, 'tcx, M> { } }; // Determine what it actually points to. - let alloc_actual_mutbl = mutability(self.ecx, alloc_id); + let alloc_actual_mutbl = + global_alloc.mutability(*self.ecx.tcx, self.ecx.param_env); // Mutable pointer to immutable memory is no good. if ptr_expected_mutbl == Mutability::Mut && alloc_actual_mutbl == Mutability::Not @@ -842,9 +843,16 @@ impl<'rt, 'tcx, M: Machine<'tcx>> ValidityVisitor<'rt, 'tcx, M> { } fn in_mutable_memory(&self, val: &PlaceTy<'tcx, M::Provenance>) -> bool { + debug_assert!(self.ctfe_mode.is_some()); if let Some(mplace) = val.as_mplace_or_local().left() { if let Some(alloc_id) = mplace.ptr().provenance.and_then(|p| p.get_alloc_id()) { - mutability(self.ecx, alloc_id).is_mut() + let tcx = *self.ecx.tcx; + // Everything must be already interned. + let mutbl = tcx.global_alloc(alloc_id).mutability(tcx, self.ecx.param_env); + if let Some((_, alloc)) = self.ecx.memory.alloc_map.get(alloc_id) { + assert_eq!(alloc.mutability, mutbl); + } + mutbl.is_mut() } else { // No memory at all. false @@ -1016,53 +1024,6 @@ impl<'rt, 'tcx, M: Machine<'tcx>> ValidityVisitor<'rt, 'tcx, M> { } } -/// Returns whether the allocation is mutable, and whether it's actually a static. -/// For "root" statics we look at the type to account for interior -/// mutability; for nested statics we have no type and directly use the annotated mutability. -fn mutability<'tcx>(ecx: &InterpCx<'tcx, impl Machine<'tcx>>, alloc_id: AllocId) -> Mutability { - // Let's see what kind of memory this points to. - // We're not using `try_global_alloc` since dangling pointers have already been handled. - match ecx.tcx.global_alloc(alloc_id) { - GlobalAlloc::Static(did) => { - let DefKind::Static { safety: _, mutability, nested } = ecx.tcx.def_kind(did) else { - bug!() - }; - if nested { - assert!( - ecx.memory.alloc_map.get(alloc_id).is_none(), - "allocations of nested statics are already interned: {alloc_id:?}, {did:?}" - ); - // Nested statics in a `static` are never interior mutable, - // so just use the declared mutability. - mutability - } else { - let mutability = match mutability { - Mutability::Not - if !ecx - .tcx - .type_of(did) - .no_bound_vars() - .expect("statics should not have generic parameters") - .is_freeze(*ecx.tcx, ty::ParamEnv::reveal_all()) => - { - Mutability::Mut - } - _ => mutability, - }; - if let Some((_, alloc)) = ecx.memory.alloc_map.get(alloc_id) { - assert_eq!(alloc.mutability, mutability); - } - mutability - } - } - GlobalAlloc::Memory(alloc) => alloc.inner().mutability, - GlobalAlloc::Function { .. } | GlobalAlloc::VTable(..) => { - // These are immutable, we better don't allow mutable pointers here. - Mutability::Not - } - } -} - impl<'rt, 'tcx, M: Machine<'tcx>> ValueVisitor<'tcx, M> for ValidityVisitor<'rt, 'tcx, M> { type V = PlaceTy<'tcx, M::Provenance>; diff --git a/compiler/rustc_const_eval/src/interpret/visitor.rs b/compiler/rustc_const_eval/src/interpret/visitor.rs index 647917dbb67..76ab0bb544f 100644 --- a/compiler/rustc_const_eval/src/interpret/visitor.rs +++ b/compiler/rustc_const_eval/src/interpret/visitor.rs @@ -3,11 +3,11 @@ use std::num::NonZero; +use rustc_abi::{FieldIdx, FieldsShape, VariantIdx, Variants}; use rustc_index::IndexVec; use rustc_middle::mir::interpret::InterpResult; use rustc_middle::ty::layout::LayoutOf; use rustc_middle::ty::{self, Ty}; -use rustc_target::abi::{FieldIdx, FieldsShape, VariantIdx, Variants}; use tracing::trace; use super::{InterpCx, MPlaceTy, Machine, Projectable, interp_ok, throw_inval}; diff --git a/compiler/rustc_const_eval/src/util/alignment.rs b/compiler/rustc_const_eval/src/util/alignment.rs index 5ad55968398..6fa7d369229 100644 --- a/compiler/rustc_const_eval/src/util/alignment.rs +++ b/compiler/rustc_const_eval/src/util/alignment.rs @@ -1,6 +1,6 @@ +use rustc_abi::Align; use rustc_middle::mir::*; use rustc_middle::ty::{self, TyCtxt}; -use rustc_target::abi::Align; use tracing::debug; /// Returns `true` if this place is allowed to be less aligned |