diff options
Diffstat (limited to 'compiler/rustc_middle/src/mir/syntax.rs')
| -rw-r--r-- | compiler/rustc_middle/src/mir/syntax.rs | 50 |
1 files changed, 39 insertions, 11 deletions
diff --git a/compiler/rustc_middle/src/mir/syntax.rs b/compiler/rustc_middle/src/mir/syntax.rs index 93800d484..3e474c1d3 100644 --- a/compiler/rustc_middle/src/mir/syntax.rs +++ b/compiler/rustc_middle/src/mir/syntax.rs @@ -16,7 +16,7 @@ use rustc_ast::{InlineAsmOptions, InlineAsmTemplatePiece}; use rustc_hir::def_id::DefId; use rustc_hir::{self as hir}; use rustc_hir::{self, GeneratorKind}; -use rustc_index::vec::IndexVec; +use rustc_index::IndexVec; use rustc_target::abi::{FieldIdx, VariantIdx}; use rustc_ast::Mutability; @@ -256,7 +256,7 @@ pub enum StatementKind<'tcx> { /// **Needs clarification**: The implication of the above idea would be that assignment implies /// that the resulting value is initialized. I believe we could commit to this separately from /// committing to whatever part of the memory model we would need to decide on to make the above - /// paragragh precise. Do we want to? + /// paragraph precise. Do we want to? /// /// Assignments in which the types of the place and rvalue differ are not well-formed. /// @@ -336,9 +336,8 @@ pub enum StatementKind<'tcx> { /// This is especially useful for `let _ = PLACE;` bindings that desugar to a single /// `PlaceMention(PLACE)`. /// - /// When executed at runtime this is a nop. - /// - /// Disallowed after drop elaboration. + /// When executed at runtime, this computes the given place, but then discards + /// it without doing a load. It is UB if the place is not pointing to live memory. PlaceMention(Box<Place<'tcx>>), /// Encodes a user's type ascription. These need to be preserved @@ -609,7 +608,11 @@ pub enum TerminatorKind<'tcx> { /// > The drop glue is executed if, among all statements executed within this `Body`, an assignment to /// > the place or one of its "parents" occurred more recently than a move out of it. This does not /// > consider indirect assignments. - Drop { place: Place<'tcx>, target: BasicBlock, unwind: UnwindAction }, + /// + /// The `replace` flag indicates whether this terminator was created as part of an assignment. + /// This should only be used for diagnostic purposes, and does not have any operational + /// meaning. + Drop { place: Place<'tcx>, target: BasicBlock, unwind: UnwindAction, replace: bool }, /// Roughly speaking, evaluates the `func` operand and the arguments, and starts execution of /// the referred to function. The operand types must match the argument types of the function. @@ -657,7 +660,7 @@ pub enum TerminatorKind<'tcx> { Assert { cond: Operand<'tcx>, expected: bool, - msg: AssertMessage<'tcx>, + msg: Box<AssertMessage<'tcx>>, target: BasicBlock, unwind: UnwindAction, }, @@ -755,6 +758,29 @@ pub enum TerminatorKind<'tcx> { }, } +impl TerminatorKind<'_> { + /// Returns a simple string representation of a `TerminatorKind` variant, independent of any + /// values it might hold (e.g. `TerminatorKind::Call` always returns `"Call"`). + pub const fn name(&self) -> &'static str { + match self { + TerminatorKind::Goto { .. } => "Goto", + TerminatorKind::SwitchInt { .. } => "SwitchInt", + TerminatorKind::Resume => "Resume", + TerminatorKind::Terminate => "Terminate", + TerminatorKind::Return => "Return", + TerminatorKind::Unreachable => "Unreachable", + TerminatorKind::Drop { .. } => "Drop", + TerminatorKind::Call { .. } => "Call", + TerminatorKind::Assert { .. } => "Assert", + TerminatorKind::Yield { .. } => "Yield", + TerminatorKind::GeneratorDrop => "GeneratorDrop", + TerminatorKind::FalseEdge { .. } => "FalseEdge", + TerminatorKind::FalseUnwind { .. } => "FalseUnwind", + TerminatorKind::InlineAsm { .. } => "InlineAsm", + } + } +} + /// Action to be taken when a stack unwind happens. #[derive(Copy, Clone, Debug, PartialEq, Eq, TyEncodable, TyDecodable, Hash, HashStable)] #[derive(TypeFoldable, TypeVisitable)] @@ -1002,7 +1028,7 @@ pub type PlaceElem<'tcx> = ProjectionElem<Local, Ty<'tcx>>; /// This is what is implemented in miri today. Are these the semantics we want for MIR? Is this /// something we can even decide without knowing more about Rust's memory model? /// -/// **Needs clarifiation:** Is loading a place that has its variant index set well-formed? Miri +/// **Needs clarification:** Is loading a place that has its variant index set well-formed? Miri /// currently implements it, but it seems like this may be something to check against in the /// validator. #[derive(Clone, PartialEq, TyEncodable, TyDecodable, Hash, HashStable, TypeFoldable, TypeVisitable)] @@ -1120,7 +1146,7 @@ pub enum Rvalue<'tcx> { CheckedBinaryOp(BinOp, Box<(Operand<'tcx>, Operand<'tcx>)>), /// Computes a value as described by the operation. - NullaryOp(NullOp, Ty<'tcx>), + NullaryOp(NullOp<'tcx>, Ty<'tcx>), /// Exactly like `BinaryOp`, but less operands. /// @@ -1216,12 +1242,14 @@ pub enum AggregateKind<'tcx> { Generator(DefId, SubstsRef<'tcx>, hir::Movability), } -#[derive(Copy, Clone, Debug, PartialEq, Eq, TyEncodable, TyDecodable, Hash, HashStable)] -pub enum NullOp { +#[derive(Clone, Debug, PartialEq, Eq, TyEncodable, TyDecodable, Hash, HashStable)] +pub enum NullOp<'tcx> { /// Returns the size of a value of that type SizeOf, /// Returns the minimum alignment of a type AlignOf, + /// Returns the offset of a field + OffsetOf(&'tcx List<FieldIdx>), } #[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)] |