diff options
Diffstat (limited to 'compiler/rustc_const_eval/src/const_eval')
| -rw-r--r-- | compiler/rustc_const_eval/src/const_eval/eval_queries.rs | 30 | ||||
| -rw-r--r-- | compiler/rustc_const_eval/src/const_eval/machine.rs | 50 |
2 files changed, 55 insertions, 25 deletions
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 96b3ec6f187..594b98f34ef 100644 --- a/compiler/rustc_const_eval/src/const_eval/eval_queries.rs +++ b/compiler/rustc_const_eval/src/const_eval/eval_queries.rs @@ -10,7 +10,6 @@ use rustc_middle::traits::Reveal; use rustc_middle::ty::layout::LayoutOf; use rustc_middle::ty::print::with_no_trimmed_paths; use rustc_middle::ty::{self, Ty, TyCtxt}; -use rustc_session::lint; use rustc_span::def_id::LocalDefId; use rustc_span::{Span, DUMMY_SP}; use rustc_target::abi::{self, Abi}; @@ -18,13 +17,12 @@ use tracing::{debug, instrument, trace}; use super::{CanAccessMutGlobal, CompileTimeInterpCx, CompileTimeMachine}; use crate::const_eval::CheckAlignment; -use crate::errors::{self, ConstEvalError, DanglingPtrInFinal}; use crate::interpret::{ create_static_alloc, eval_nullary_intrinsic, intern_const_alloc_recursive, throw_exhaust, CtfeValidationMode, GlobalId, Immediate, InternKind, InternResult, InterpCx, InterpError, InterpResult, MPlaceTy, MemoryKind, OpTy, RefTracking, StackPopCleanup, }; -use crate::CTRL_C_RECEIVED; +use crate::{errors, CTRL_C_RECEIVED}; // Returns a pointer to where the result lives #[instrument(level = "trace", skip(ecx, body))] @@ -94,7 +92,7 @@ fn eval_body_using_ecx<'tcx, R: InterpretationResult<'tcx>>( let intern_result = intern_const_alloc_recursive(ecx, intern_kind, &ret); // Since evaluation had no errors, validate the resulting constant. - const_validate_mplace(&ecx, &ret, cid)?; + const_validate_mplace(ecx, &ret, cid)?; // Only report this after validation, as validaiton produces much better diagnostics. // FIXME: ensure validation always reports this and stop making interning care about it. @@ -105,18 +103,15 @@ fn eval_body_using_ecx<'tcx, R: InterpretationResult<'tcx>>( return Err(ecx .tcx .dcx() - .emit_err(DanglingPtrInFinal { span: ecx.tcx.span, kind: intern_kind }) + .emit_err(errors::DanglingPtrInFinal { span: ecx.tcx.span, kind: intern_kind }) .into()); } Err(InternResult::FoundBadMutablePointer) => { - // only report mutable pointers if there were no dangling pointers - let err_diag = errors::MutablePtrInFinal { span: ecx.tcx.span, kind: intern_kind }; - ecx.tcx.emit_node_span_lint( - lint::builtin::CONST_EVAL_MUTABLE_PTR_IN_FINAL_VALUE, - ecx.machine.best_lint_scope(*ecx.tcx), - err_diag.span, - err_diag, - ) + return Err(ecx + .tcx + .dcx() + .emit_err(errors::MutablePtrInFinal { span: ecx.tcx.span, kind: intern_kind }) + .into()); } } @@ -391,7 +386,7 @@ fn eval_in_interpreter<'tcx, R: InterpretationResult<'tcx>>( #[inline(always)] fn const_validate_mplace<'tcx>( - ecx: &InterpCx<'tcx, CompileTimeMachine<'tcx>>, + ecx: &mut InterpCx<'tcx, CompileTimeMachine<'tcx>>, mplace: &MPlaceTy<'tcx>, cid: GlobalId<'tcx>, ) -> Result<(), ErrorHandled> { @@ -448,7 +443,12 @@ fn report_eval_error<'tcx>( error, DUMMY_SP, || super::get_span_and_frames(ecx.tcx, ecx.stack()), - |span, frames| ConstEvalError { span, error_kind: kind, instance, frame_notes: frames }, + |span, frames| errors::ConstEvalError { + span, + error_kind: kind, + instance, + frame_notes: frames, + }, ) } diff --git a/compiler/rustc_const_eval/src/const_eval/machine.rs b/compiler/rustc_const_eval/src/const_eval/machine.rs index 9c1fef095f5..6a691abae02 100644 --- a/compiler/rustc_const_eval/src/const_eval/machine.rs +++ b/compiler/rustc_const_eval/src/const_eval/machine.rs @@ -1,16 +1,16 @@ -use std::borrow::Borrow; +use std::borrow::{Borrow, Cow}; use std::fmt; use std::hash::Hash; use std::ops::ControlFlow; use rustc_ast::Mutability; -use rustc_data_structures::fx::{FxIndexMap, IndexEntry}; +use rustc_data_structures::fx::{FxHashMap, FxIndexMap, IndexEntry}; use rustc_hir::def_id::{DefId, LocalDefId}; use rustc_hir::{self as hir, LangItem, CRATE_HIR_ID}; use rustc_middle::mir::AssertMessage; use rustc_middle::query::TyCtxtAt; use rustc_middle::ty::layout::{FnAbiOf, TyAndLayout}; -use rustc_middle::ty::{self, TyCtxt}; +use rustc_middle::ty::{self, Ty, TyCtxt}; use rustc_middle::{bug, mir}; use rustc_span::symbol::{sym, Symbol}; use rustc_span::Span; @@ -24,8 +24,8 @@ use crate::fluent_generated as fluent; use crate::interpret::{ self, compile_time_machine, err_ub, throw_exhaust, throw_inval, throw_ub_custom, throw_unsup, throw_unsup_format, AllocId, AllocRange, ConstAllocation, CtfeProvenance, FnArg, Frame, - GlobalAlloc, ImmTy, InterpCx, InterpResult, MPlaceTy, OpTy, Pointer, PointerArithmetic, Scalar, - StackPopCleanup, + GlobalAlloc, ImmTy, InterpCx, InterpResult, MPlaceTy, OpTy, Pointer, PointerArithmetic, + RangeSet, Scalar, StackPopCleanup, }; /// When hitting this many interpreted terminators we emit a deny by default lint @@ -65,6 +65,9 @@ pub struct CompileTimeMachine<'tcx> { /// storing the result in the given `AllocId`. /// Used to prevent reads from a static's base allocation, as that may allow for self-initialization loops. pub(crate) static_root_ids: Option<(AllocId, LocalDefId)>, + + /// A cache of "data range" computations for unions (i.e., the offsets of non-padding bytes). + union_data_ranges: FxHashMap<Ty<'tcx>, RangeSet>, } #[derive(Copy, Clone)] @@ -99,6 +102,7 @@ impl<'tcx> CompileTimeMachine<'tcx> { can_access_mut_global, check_alignment, static_root_ids: None, + union_data_ranges: FxHashMap::default(), } } } @@ -714,16 +718,29 @@ impl<'tcx> interpret::Machine<'tcx> for CompileTimeMachine<'tcx> { _kind: mir::RetagKind, val: &ImmTy<'tcx, CtfeProvenance>, ) -> InterpResult<'tcx, ImmTy<'tcx, CtfeProvenance>> { - // If it's a frozen shared reference that's not already immutable, make it immutable. + // If it's a frozen shared reference that's not already immutable, potentially make it immutable. // (Do nothing on `None` provenance, that cannot store immutability anyway.) if let ty::Ref(_, ty, mutbl) = val.layout.ty.kind() && *mutbl == Mutability::Not - && val.to_scalar_and_meta().0.to_pointer(ecx)?.provenance.is_some_and(|p| !p.immutable()) - // That next check is expensive, that's why we have all the guards above. - && ty.is_freeze(*ecx.tcx, ecx.param_env) + && val + .to_scalar_and_meta() + .0 + .to_pointer(ecx)? + .provenance + .is_some_and(|p| !p.immutable()) { + // That next check is expensive, that's why we have all the guards above. + let is_immutable = ty.is_freeze(*ecx.tcx, ecx.param_env); let place = ecx.ref_to_mplace(val)?; - let new_place = place.map_provenance(CtfeProvenance::as_immutable); + let new_place = if is_immutable { + place.map_provenance(CtfeProvenance::as_immutable) + } else { + // Even if it is not immutable, remember that it is a shared reference. + // This allows it to become part of the final value of the constant. + // (See <https://github.com/rust-lang/rust/pull/128543> for why we allow this + // even when there is interior mutability.) + place.map_provenance(CtfeProvenance::as_shared_ref) + }; Ok(ImmTy::from_immediate(new_place.to_ref(ecx), val.layout)) } else { Ok(val.clone()) @@ -766,6 +783,19 @@ impl<'tcx> interpret::Machine<'tcx> for CompileTimeMachine<'tcx> { } Ok(()) } + + fn cached_union_data_range<'e>( + ecx: &'e mut InterpCx<'tcx, Self>, + ty: Ty<'tcx>, + compute_range: impl FnOnce() -> RangeSet, + ) -> Cow<'e, RangeSet> { + if ecx.tcx.sess.opts.unstable_opts.extra_const_ub_checks { + Cow::Borrowed(ecx.machine.union_data_ranges.entry(ty).or_insert_with(compute_range)) + } else { + // Don't bother caching, we're only doing one validation at the end anyway. + Cow::Owned(compute_range()) + } + } } // Please do not add any code below the above `Machine` trait impl. I (oli-obk) plan more cleanups |