diff options
Diffstat (limited to 'compiler')
25 files changed, 56 insertions, 183 deletions
diff --git a/compiler/rustc_borrowck/src/lib.rs b/compiler/rustc_borrowck/src/lib.rs index 5d2dda8b0e7..f196bd04d0e 100644 --- a/compiler/rustc_borrowck/src/lib.rs +++ b/compiler/rustc_borrowck/src/lib.rs @@ -1557,9 +1557,8 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, '_, 'tcx> { ); } - &(Rvalue::Len(place) | Rvalue::Discriminant(place)) => { + &Rvalue::Discriminant(place) => { let af = match *rvalue { - Rvalue::Len(..) => Some(ArtificialField::ArrayLength), Rvalue::Discriminant(..) => None, _ => unreachable!(), }; diff --git a/compiler/rustc_borrowck/src/polonius/legacy/loan_invalidations.rs b/compiler/rustc_borrowck/src/polonius/legacy/loan_invalidations.rs index 99dd0b2dd46..c2ad6fcb4b7 100644 --- a/compiler/rustc_borrowck/src/polonius/legacy/loan_invalidations.rs +++ b/compiler/rustc_borrowck/src/polonius/legacy/loan_invalidations.rs @@ -306,16 +306,11 @@ impl<'a, 'tcx> LoanInvalidationsGenerator<'a, 'tcx> { self.consume_operand(location, op); } - &(Rvalue::Len(place) | Rvalue::Discriminant(place)) => { - let af = match rvalue { - Rvalue::Len(..) => Some(ArtificialField::ArrayLength), - Rvalue::Discriminant(..) => None, - _ => unreachable!(), - }; + &Rvalue::Discriminant(place) => { self.access_place( location, place, - (Shallow(af), Read(ReadKind::Copy)), + (Shallow(None), Read(ReadKind::Copy)), LocalMutationIsAllowed::No, ); } diff --git a/compiler/rustc_borrowck/src/type_check/mod.rs b/compiler/rustc_borrowck/src/type_check/mod.rs index 8c5447fe1e9..dcedf0b1532 100644 --- a/compiler/rustc_borrowck/src/type_check/mod.rs +++ b/compiler/rustc_borrowck/src/type_check/mod.rs @@ -1631,7 +1631,6 @@ impl<'a, 'tcx> Visitor<'tcx> for TypeChecker<'a, 'tcx> { | Rvalue::BinaryOp(..) | Rvalue::RawPtr(..) | Rvalue::ThreadLocalRef(..) - | Rvalue::Len(..) | Rvalue::Discriminant(..) | Rvalue::NullaryOp(NullOp::OffsetOf(..), _) => {} } @@ -2201,7 +2200,6 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> { | Rvalue::Repeat(..) | Rvalue::Ref(..) | Rvalue::RawPtr(..) - | Rvalue::Len(..) | Rvalue::Cast(..) | Rvalue::ShallowInitBox(..) | Rvalue::BinaryOp(..) diff --git a/compiler/rustc_codegen_cranelift/src/base.rs b/compiler/rustc_codegen_cranelift/src/base.rs index 3a28dd7e73c..41e11e1de61 100644 --- a/compiler/rustc_codegen_cranelift/src/base.rs +++ b/compiler/rustc_codegen_cranelift/src/base.rs @@ -834,12 +834,6 @@ fn codegen_stmt<'tcx>(fx: &mut FunctionCx<'_, '_, 'tcx>, cur_block: Block, stmt: fx.bcx.ins().nop(); } } - Rvalue::Len(place) => { - let place = codegen_place(fx, place); - let usize_layout = fx.layout_of(fx.tcx.types.usize); - let len = codegen_array_len(fx, place); - lval.write_cvalue(fx, CValue::by_val(len, usize_layout)); - } Rvalue::ShallowInitBox(ref operand, content_ty) => { let content_ty = fx.monomorphize(content_ty); let box_layout = fx.layout_of(Ty::new_box(fx.tcx, content_ty)); diff --git a/compiler/rustc_codegen_ssa/src/mir/rvalue.rs b/compiler/rustc_codegen_ssa/src/mir/rvalue.rs index f8755874014..c30e6a50505 100644 --- a/compiler/rustc_codegen_ssa/src/mir/rvalue.rs +++ b/compiler/rustc_codegen_ssa/src/mir/rvalue.rs @@ -7,9 +7,9 @@ use rustc_middle::{bug, mir, span_bug}; use rustc_session::config::OptLevel; use tracing::{debug, instrument}; +use super::FunctionCx; use super::operand::{OperandRef, OperandRefBuilder, OperandValue}; use super::place::{PlaceRef, PlaceValue, codegen_tag_value}; -use super::{FunctionCx, LocalRef}; use crate::common::{IntPredicate, TypeKind}; use crate::traits::*; use crate::{MemFlags, base}; @@ -510,14 +510,6 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> { self.codegen_place_to_pointer(bx, place, mk_ptr) } - mir::Rvalue::Len(place) => { - let size = self.evaluate_array_len(bx, place); - OperandRef { - val: OperandValue::Immediate(size), - layout: bx.cx().layout_of(bx.tcx().types.usize), - } - } - mir::Rvalue::BinaryOp(op_with_overflow, box (ref lhs, ref rhs)) if let Some(op) = op_with_overflow.overflowing_to_wrapping() => { @@ -749,21 +741,6 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> { } } - fn evaluate_array_len(&mut self, bx: &mut Bx, place: mir::Place<'tcx>) -> Bx::Value { - // ZST are passed as operands and require special handling - // because codegen_place() panics if Local is operand. - if let Some(index) = place.as_local() - && let LocalRef::Operand(op) = self.locals[index] - && let ty::Array(_, n) = op.layout.ty.kind() - { - let n = n.try_to_target_usize(bx.tcx()).expect("expected monomorphic const in codegen"); - return bx.cx().const_usize(n); - } - // use common size calculation for non zero-sized types - let cg_value = self.codegen_place(bx, place.as_ref()); - cg_value.len(bx.cx()) - } - /// Codegen an `Rvalue::RawPtr` or `Rvalue::Ref` fn codegen_place_to_pointer( &mut self, diff --git a/compiler/rustc_const_eval/src/check_consts/check.rs b/compiler/rustc_const_eval/src/check_consts/check.rs index ca707b50d50..3397bd9a68e 100644 --- a/compiler/rustc_const_eval/src/check_consts/check.rs +++ b/compiler/rustc_const_eval/src/check_consts/check.rs @@ -573,8 +573,7 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { Rvalue::Use(_) | Rvalue::CopyForDeref(..) | Rvalue::Repeat(..) - | Rvalue::Discriminant(..) - | Rvalue::Len(_) => {} + | Rvalue::Discriminant(..) => {} Rvalue::Aggregate(kind, ..) => { if let AggregateKind::Coroutine(def_id, ..) = kind.as_ref() diff --git a/compiler/rustc_const_eval/src/check_consts/qualifs.rs b/compiler/rustc_const_eval/src/check_consts/qualifs.rs index faf41f1658b..34d1fdd8c86 100644 --- a/compiler/rustc_const_eval/src/check_consts/qualifs.rs +++ b/compiler/rustc_const_eval/src/check_consts/qualifs.rs @@ -232,9 +232,7 @@ where Q::in_any_value_of_ty(cx, rvalue.ty(cx.body, cx.tcx)) } - Rvalue::Discriminant(place) | Rvalue::Len(place) => { - in_place::<Q, _>(cx, in_local, place.as_ref()) - } + Rvalue::Discriminant(place) => in_place::<Q, _>(cx, in_local, place.as_ref()), Rvalue::CopyForDeref(place) => in_place::<Q, _>(cx, in_local, place.as_ref()), diff --git a/compiler/rustc_const_eval/src/check_consts/resolver.rs b/compiler/rustc_const_eval/src/check_consts/resolver.rs index d98e5027e4d..664dda8701a 100644 --- a/compiler/rustc_const_eval/src/check_consts/resolver.rs +++ b/compiler/rustc_const_eval/src/check_consts/resolver.rs @@ -197,7 +197,6 @@ where | mir::Rvalue::CopyForDeref(..) | mir::Rvalue::ThreadLocalRef(..) | mir::Rvalue::Repeat(..) - | mir::Rvalue::Len(..) | mir::Rvalue::BinaryOp(..) | mir::Rvalue::NullaryOp(..) | mir::Rvalue::UnaryOp(..) diff --git a/compiler/rustc_const_eval/src/interpret/step.rs b/compiler/rustc_const_eval/src/interpret/step.rs index 46950d60f8c..923e00ad4cf 100644 --- a/compiler/rustc_const_eval/src/interpret/step.rs +++ b/compiler/rustc_const_eval/src/interpret/step.rs @@ -17,7 +17,7 @@ use tracing::{info, instrument, trace}; use super::{ FnArg, FnVal, ImmTy, Immediate, InterpCx, InterpResult, Machine, MemPlaceMeta, PlaceTy, - Projectable, Scalar, interp_ok, throw_ub, throw_unsup_format, + Projectable, interp_ok, throw_ub, throw_unsup_format, }; use crate::interpret::EnteredTraceSpan; use crate::{enter_trace_span, util}; @@ -225,12 +225,6 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { self.write_repeat(operand, &dest)?; } - Len(place) => { - let src = self.eval_place(place)?; - let len = src.len(self)?; - self.write_scalar(Scalar::from_target_usize(len, self), &dest)?; - } - Ref(_, borrow_kind, place) => { let src = self.eval_place(place)?; let place = self.force_allocation(&src)?; diff --git a/compiler/rustc_middle/src/mir/pretty.rs b/compiler/rustc_middle/src/mir/pretty.rs index f9d0a5f0a3b..96148fd5b92 100644 --- a/compiler/rustc_middle/src/mir/pretty.rs +++ b/compiler/rustc_middle/src/mir/pretty.rs @@ -1062,7 +1062,6 @@ impl<'tcx> Debug for Rvalue<'tcx> { pretty_print_const(b, fmt, false)?; write!(fmt, "]") } - Len(ref a) => write!(fmt, "Len({a:?})"), Cast(ref kind, ref place, ref ty) => { with_no_trimmed_paths!(write!(fmt, "{place:?} as {ty} ({kind:?})")) } diff --git a/compiler/rustc_middle/src/mir/statement.rs b/compiler/rustc_middle/src/mir/statement.rs index ec2a8e86077..28294b47e90 100644 --- a/compiler/rustc_middle/src/mir/statement.rs +++ b/compiler/rustc_middle/src/mir/statement.rs @@ -697,7 +697,6 @@ impl<'tcx> Rvalue<'tcx> { | Rvalue::Ref(_, _, _) | Rvalue::ThreadLocalRef(_) | Rvalue::RawPtr(_, _) - | Rvalue::Len(_) | Rvalue::Cast( CastKind::IntToInt | CastKind::FloatToInt @@ -739,7 +738,6 @@ impl<'tcx> Rvalue<'tcx> { let place_ty = place.ty(local_decls, tcx).ty; Ty::new_ptr(tcx, place_ty, kind.to_mutbl_lossy()) } - Rvalue::Len(..) => tcx.types.usize, Rvalue::Cast(.., ty) => ty, Rvalue::BinaryOp(op, box (ref lhs, ref rhs)) => { let lhs_ty = lhs.ty(local_decls, tcx); diff --git a/compiler/rustc_middle/src/mir/syntax.rs b/compiler/rustc_middle/src/mir/syntax.rs index d402ea4b04f..e6c8512564e 100644 --- a/compiler/rustc_middle/src/mir/syntax.rs +++ b/compiler/rustc_middle/src/mir/syntax.rs @@ -1407,16 +1407,6 @@ pub enum Rvalue<'tcx> { /// model. RawPtr(RawPtrKind, Place<'tcx>), - /// Yields the length of the place, as a `usize`. - /// - /// If the type of the place is an array, this is the array length. For slices (`[T]`, not - /// `&[T]`) this accesses the place's metadata to determine the length. This rvalue is - /// ill-formed for places of other types. - /// - /// This cannot be a `UnOp(PtrMetadata, _)` because that expects a value, and we only - /// have a place, and `UnOp(PtrMetadata, RawPtr(place))` is not a thing. - Len(Place<'tcx>), - /// Performs essentially all of the casts that can be performed via `as`. /// /// This allows for casts from/to a variety of types. diff --git a/compiler/rustc_middle/src/mir/visit.rs b/compiler/rustc_middle/src/mir/visit.rs index b498b7b8912..07a15b3cd18 100644 --- a/compiler/rustc_middle/src/mir/visit.rs +++ b/compiler/rustc_middle/src/mir/visit.rs @@ -717,14 +717,6 @@ macro_rules! make_mir_visitor { self.visit_place(path, ctx, location); } - Rvalue::Len(path) => { - self.visit_place( - path, - PlaceContext::NonMutatingUse(NonMutatingUseContext::Inspect), - location - ); - } - Rvalue::Cast(_cast_kind, operand, ty) => { self.visit_operand(operand, location); self.visit_ty($(& $mutability)? *ty, TyContext::Location(location)); diff --git a/compiler/rustc_mir_build/src/builder/custom/parse/instruction.rs b/compiler/rustc_mir_build/src/builder/custom/parse/instruction.rs index 41d3aefcbe6..54490e00509 100644 --- a/compiler/rustc_mir_build/src/builder/custom/parse/instruction.rs +++ b/compiler/rustc_mir_build/src/builder/custom/parse/instruction.rs @@ -229,6 +229,11 @@ impl<'a, 'tcx> ParseCtxt<'a, 'tcx> { let source = self.parse_operand(args[0])?; Ok(Rvalue::Cast(CastKind::PtrToPtr, source, expr.ty)) }, + @call(mir_cast_unsize, args) => { + let source = self.parse_operand(args[0])?; + let kind = CastKind::PointerCoercion(ty::adjustment::PointerCoercion::Unsize, CoercionSource::AsCast); + Ok(Rvalue::Cast(kind, source, expr.ty)) + }, @call(mir_checked, args) => { parse_by_kind!(self, args[0], _, "binary op", ExprKind::Binary { op, lhs, rhs } => { @@ -247,7 +252,6 @@ impl<'a, 'tcx> ParseCtxt<'a, 'tcx> { let offset = self.parse_operand(args[1])?; Ok(Rvalue::BinaryOp(BinOp::Offset, Box::new((ptr, offset)))) }, - @call(mir_len, args) => Ok(Rvalue::Len(self.parse_place(args[0])?)), @call(mir_ptr_metadata, args) => Ok(Rvalue::UnaryOp(UnOp::PtrMetadata, self.parse_operand(args[0])?)), @call(mir_copy_for_deref, args) => Ok(Rvalue::CopyForDeref(self.parse_place(args[0])?)), ExprKind::Borrow { borrow_kind, arg } => Ok( diff --git a/compiler/rustc_mir_build/src/builder/expr/as_place.rs b/compiler/rustc_mir_build/src/builder/expr/as_place.rs index 7c851ec465b..5a6bd2f413c 100644 --- a/compiler/rustc_mir_build/src/builder/expr/as_place.rs +++ b/compiler/rustc_mir_build/src/builder/expr/as_place.rs @@ -663,7 +663,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { /// /// For arrays it'll be `Operand::Constant` with the actual length; /// For slices it'll be `Operand::Move` of a local using `PtrMetadata`. - fn len_of_slice_or_array( + pub(in crate::builder) fn len_of_slice_or_array( &mut self, block: BasicBlock, place: Place<'tcx>, diff --git a/compiler/rustc_mir_build/src/builder/matches/test.rs b/compiler/rustc_mir_build/src/builder/matches/test.rs index d03794fe2d5..1b6d96e49f0 100644 --- a/compiler/rustc_mir_build/src/builder/matches/test.rs +++ b/compiler/rustc_mir_build/src/builder/matches/test.rs @@ -309,7 +309,8 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { let actual = self.temp(usize_ty, test.span); // actual = len(place) - self.cfg.push_assign(block, source_info, actual, Rvalue::Len(place)); + let length_op = self.len_of_slice_or_array(block, place, test.span, source_info); + self.cfg.push_assign(block, source_info, actual, Rvalue::Use(length_op)); // expected = <N> let expected = self.push_usize(block, source_info, len); diff --git a/compiler/rustc_mir_dataflow/src/impls/borrowed_locals.rs b/compiler/rustc_mir_dataflow/src/impls/borrowed_locals.rs index 9abb8343432..a4e4e30a8bb 100644 --- a/compiler/rustc_mir_dataflow/src/impls/borrowed_locals.rs +++ b/compiler/rustc_mir_dataflow/src/impls/borrowed_locals.rs @@ -91,7 +91,6 @@ where | Rvalue::Use(..) | Rvalue::ThreadLocalRef(..) | Rvalue::Repeat(..) - | Rvalue::Len(..) | Rvalue::BinaryOp(..) | Rvalue::NullaryOp(..) | Rvalue::UnaryOp(..) diff --git a/compiler/rustc_mir_dataflow/src/move_paths/builder.rs b/compiler/rustc_mir_dataflow/src/move_paths/builder.rs index 48718cad597..f38bb445824 100644 --- a/compiler/rustc_mir_dataflow/src/move_paths/builder.rs +++ b/compiler/rustc_mir_dataflow/src/move_paths/builder.rs @@ -413,7 +413,6 @@ impl<'a, 'tcx, F: Fn(Ty<'tcx>) -> bool> MoveDataBuilder<'a, 'tcx, F> { Rvalue::Ref(..) | Rvalue::RawPtr(..) | Rvalue::Discriminant(..) - | Rvalue::Len(..) | Rvalue::NullaryOp( NullOp::SizeOf | NullOp::AlignOf diff --git a/compiler/rustc_mir_transform/src/dataflow_const_prop.rs b/compiler/rustc_mir_transform/src/dataflow_const_prop.rs index fe53de31f75..5c984984d3c 100644 --- a/compiler/rustc_mir_transform/src/dataflow_const_prop.rs +++ b/compiler/rustc_mir_transform/src/dataflow_const_prop.rs @@ -412,18 +412,6 @@ impl<'a, 'tcx> ConstAnalysis<'a, 'tcx> { state: &mut State<FlatSet<Scalar>>, ) -> ValueOrPlace<FlatSet<Scalar>> { let val = match rvalue { - Rvalue::Len(place) => { - let place_ty = place.ty(self.local_decls, self.tcx); - if let ty::Array(_, len) = place_ty.ty.kind() { - Const::Ty(self.tcx.types.usize, *len) - .try_eval_scalar(self.tcx, self.typing_env) - .map_or(FlatSet::Top, FlatSet::Elem) - } else if let [ProjectionElem::Deref] = place.projection[..] { - state.get_len(place.local.into(), &self.map) - } else { - FlatSet::Top - } - } Rvalue::Cast(CastKind::IntToInt | CastKind::IntToFloat, operand, ty) => { let Ok(layout) = self.tcx.layout_of(self.typing_env.as_query_input(*ty)) else { return ValueOrPlace::Value(FlatSet::Top); @@ -465,15 +453,23 @@ impl<'a, 'tcx> ConstAnalysis<'a, 'tcx> { let (val, _overflow) = self.binary_op(state, *op, left, right); val } - Rvalue::UnaryOp(op, operand) => match self.eval_operand(operand, state) { - FlatSet::Elem(value) => self - .ecx - .unary_op(*op, &value) - .discard_err() - .map_or(FlatSet::Top, |val| self.wrap_immediate(*val)), - FlatSet::Bottom => FlatSet::Bottom, - FlatSet::Top => FlatSet::Top, - }, + Rvalue::UnaryOp(op, operand) => { + if let UnOp::PtrMetadata = op + && let Some(place) = operand.place() + && let Some(len) = self.map.find_len(place.as_ref()) + { + return ValueOrPlace::Place(len); + } + match self.eval_operand(operand, state) { + FlatSet::Elem(value) => self + .ecx + .unary_op(*op, &value) + .discard_err() + .map_or(FlatSet::Top, |val| self.wrap_immediate(*val)), + FlatSet::Bottom => FlatSet::Bottom, + FlatSet::Top => FlatSet::Top, + } + } Rvalue::NullaryOp(null_op, ty) => { let Ok(layout) = self.tcx.layout_of(self.typing_env.as_query_input(*ty)) else { return ValueOrPlace::Value(FlatSet::Top); diff --git a/compiler/rustc_mir_transform/src/gvn.rs b/compiler/rustc_mir_transform/src/gvn.rs index bf6aa800d20..30e68a3f650 100644 --- a/compiler/rustc_mir_transform/src/gvn.rs +++ b/compiler/rustc_mir_transform/src/gvn.rs @@ -200,8 +200,6 @@ enum Value<'tcx> { Projection(VnIndex, ProjectionElem<VnIndex, ()>), /// Discriminant of the given value. Discriminant(VnIndex), - /// Length of an array or slice. - Len(VnIndex), // Operations. NullaryOp(NullOp<'tcx>, Ty<'tcx>), @@ -477,11 +475,6 @@ impl<'body, 'tcx> VnState<'body, 'tcx> { self.ecx.discriminant_for_variant(base.layout.ty, variant).discard_err()?; discr_value.into() } - Len(slice) => { - let slice = self.evaluated[slice].as_ref()?; - let len = slice.len(&self.ecx).discard_err()?; - ImmTy::from_uint(len, ty).into() - } NullaryOp(null_op, arg_ty) => { let arg_layout = self.ecx.layout_of(arg_ty).ok()?; if let NullOp::SizeOf | NullOp::AlignOf = null_op @@ -841,7 +834,6 @@ impl<'body, 'tcx> VnState<'body, 'tcx> { } // Operations. - Rvalue::Len(ref mut place) => return self.simplify_len(place, location), Rvalue::Cast(ref mut kind, ref mut value, to) => { return self.simplify_cast(kind, value, to, location); } @@ -1049,7 +1041,7 @@ impl<'body, 'tcx> VnState<'body, 'tcx> { if op == UnOp::PtrMetadata { let mut was_updated = false; loop { - match self.get(arg_index) { + arg_index = match self.get(arg_index) { // Pointer casts that preserve metadata, such as // `*const [i32]` <-> `*mut [i32]` <-> `*mut [f32]`. // It's critical that this not eliminate cases like @@ -1061,9 +1053,19 @@ impl<'body, 'tcx> VnState<'body, 'tcx> { Value::Cast { kind: CastKind::PtrToPtr, value: inner } if self.pointers_have_same_metadata(self.ty(*inner), arg_ty) => { - arg_index = *inner; - was_updated = true; - continue; + *inner + } + + // We have an unsizing cast, which assigns the length to wide pointer metadata. + Value::Cast { + kind: CastKind::PointerCoercion(ty::adjustment::PointerCoercion::Unsize, _), + value: from, + } if let Some(from) = self.ty(*from).builtin_deref(true) + && let ty::Array(_, len) = from.kind() + && let Some(to) = self.ty(arg_index).builtin_deref(true) + && let ty::Slice(..) = to.kind() => + { + return Some(self.insert_constant(Const::Ty(self.tcx.types.usize, *len))); } // `&mut *p`, `&raw *p`, etc don't change metadata. @@ -1072,18 +1074,16 @@ impl<'body, 'tcx> VnState<'body, 'tcx> { place.as_ref() && let Some(local_index) = self.locals[local] => { - arg_index = local_index; - was_updated = true; - continue; + local_index } - _ => { - if was_updated && let Some(op) = self.try_as_operand(arg_index, location) { - *arg_op = op; - } - break; - } - } + _ => break, + }; + was_updated = true; + } + + if was_updated && let Some(op) = self.try_as_operand(arg_index, location) { + *arg_op = op; } } @@ -1407,39 +1407,6 @@ impl<'body, 'tcx> VnState<'body, 'tcx> { Some(self.insert(to, Value::Cast { kind, value })) } - fn simplify_len(&mut self, place: &mut Place<'tcx>, location: Location) -> Option<VnIndex> { - // Trivial case: we are fetching a statically known length. - let place_ty = place.ty(self.local_decls, self.tcx).ty; - if let ty::Array(_, len) = place_ty.kind() { - return Some(self.insert_constant(Const::Ty(self.tcx.types.usize, *len))); - } - - let mut inner = self.simplify_place_value(place, location)?; - - // The length information is stored in the wide pointer. - // Reborrowing copies length information from one pointer to the other. - while let Value::Address { place: borrowed, .. } = self.get(inner) - && let [PlaceElem::Deref] = borrowed.projection[..] - && let Some(borrowed) = self.locals[borrowed.local] - { - inner = borrowed; - } - - // We have an unsizing cast, which assigns the length to wide pointer metadata. - if let Value::Cast { kind, value: from } = self.get(inner) - && let CastKind::PointerCoercion(ty::adjustment::PointerCoercion::Unsize, _) = kind - && let Some(from) = self.ty(*from).builtin_deref(true) - && let ty::Array(_, len) = from.kind() - && let Some(to) = self.ty(inner).builtin_deref(true) - && let ty::Slice(..) = to.kind() - { - return Some(self.insert_constant(Const::Ty(self.tcx.types.usize, *len))); - } - - // Fallback: a symbolic `Len`. - Some(self.insert(self.tcx.types.usize, Value::Len(inner))) - } - fn pointers_have_same_metadata(&self, left_ptr_ty: Ty<'tcx>, right_ptr_ty: Ty<'tcx>) -> bool { let left_meta_ty = left_ptr_ty.pointee_metadata_ty_or_projection(self.tcx); let right_meta_ty = right_ptr_ty.pointee_metadata_ty_or_projection(self.tcx); diff --git a/compiler/rustc_mir_transform/src/known_panics_lint.rs b/compiler/rustc_mir_transform/src/known_panics_lint.rs index 481c7941909..aaacc5866a2 100644 --- a/compiler/rustc_mir_transform/src/known_panics_lint.rs +++ b/compiler/rustc_mir_transform/src/known_panics_lint.rs @@ -441,7 +441,6 @@ impl<'mir, 'tcx> ConstPropagator<'mir, 'tcx> { | Rvalue::Use(..) | Rvalue::CopyForDeref(..) | Rvalue::Repeat(..) - | Rvalue::Len(..) | Rvalue::Cast(..) | Rvalue::ShallowInitBox(..) | Rvalue::Discriminant(..) @@ -604,20 +603,6 @@ impl<'mir, 'tcx> ConstPropagator<'mir, 'tcx> { return None; } - Len(place) => { - let len = if let ty::Array(_, n) = place.ty(self.local_decls(), self.tcx).ty.kind() - { - n.try_to_target_usize(self.tcx)? - } else { - match self.get_const(place)? { - Value::Immediate(src) => src.len(&self.ecx).discard_err()?, - Value::Aggregate { fields, .. } => fields.len() as u64, - Value::Uninit => return None, - } - }; - ImmTy::from_scalar(Scalar::from_target_usize(len, self), layout).into() - } - Ref(..) | RawPtr(..) => return None, NullaryOp(ref null_op, ty) => { diff --git a/compiler/rustc_mir_transform/src/promote_consts.rs b/compiler/rustc_mir_transform/src/promote_consts.rs index 9ea2eb4f25d..a0b0c8c990f 100644 --- a/compiler/rustc_mir_transform/src/promote_consts.rs +++ b/compiler/rustc_mir_transform/src/promote_consts.rs @@ -437,9 +437,7 @@ impl<'tcx> Validator<'_, 'tcx> { self.validate_operand(op)? } - Rvalue::Discriminant(place) | Rvalue::Len(place) => { - self.validate_place(place.as_ref())? - } + Rvalue::Discriminant(place) => self.validate_place(place.as_ref())?, Rvalue::ThreadLocalRef(_) => return Err(Unpromotable), diff --git a/compiler/rustc_mir_transform/src/validate.rs b/compiler/rustc_mir_transform/src/validate.rs index 99e4782e470..c8a9a88dc3f 100644 --- a/compiler/rustc_mir_transform/src/validate.rs +++ b/compiler/rustc_mir_transform/src/validate.rs @@ -1064,14 +1064,6 @@ impl<'a, 'tcx> Visitor<'tcx> for TypeChecker<'a, 'tcx> { } } Rvalue::Ref(..) => {} - Rvalue::Len(p) => { - let pty = p.ty(&self.body.local_decls, self.tcx).ty; - check_kinds!( - pty, - "Cannot compute length of non-array type {:?}", - ty::Array(..) | ty::Slice(..) - ); - } Rvalue::BinaryOp(op, vals) => { use BinOp::*; let a = vals.0.ty(&self.body.local_decls, self.tcx); diff --git a/compiler/rustc_public/src/unstable/convert/stable/mir.rs b/compiler/rustc_public/src/unstable/convert/stable/mir.rs index be8ee80bed3..b10af6526ea 100644 --- a/compiler/rustc_public/src/unstable/convert/stable/mir.rs +++ b/compiler/rustc_public/src/unstable/convert/stable/mir.rs @@ -215,7 +215,6 @@ impl<'tcx> Stable<'tcx> for mir::Rvalue<'tcx> { mutability.stable(tables, cx), place.stable(tables, cx), ), - Len(place) => crate::mir::Rvalue::Len(place.stable(tables, cx)), Cast(cast_kind, op, ty) => crate::mir::Rvalue::Cast( cast_kind.stable(tables, cx), op.stable(tables, cx), diff --git a/compiler/rustc_span/src/symbol.rs b/compiler/rustc_span/src/symbol.rs index cdb0b5b58da..16b8b46f97c 100644 --- a/compiler/rustc_span/src/symbol.rs +++ b/compiler/rustc_span/src/symbol.rs @@ -1413,6 +1413,7 @@ symbols! { mir_call, mir_cast_ptr_to_ptr, mir_cast_transmute, + mir_cast_unsize, mir_checked, mir_copy_for_deref, mir_debuginfo, |