Remove StaticKind::Promoted

Author: spastorino

src/librustc/mir/mod.rs

@@ -1687,7 +1687,7 @@ pub enum PlaceBase<'tcx> {
 )]
 pub struct Static<'tcx> {
     pub ty: Ty<'tcx>,
-    pub kind: StaticKind<'tcx>,
+    pub kind: StaticKind,
     /// The `DefId` of the item this static was declared in. For promoted values, usually, this is
     /// the same as the `DefId` of the `mir::Body` containing the `Place` this promoted appears in.
     /// However, after inlining, that might no longer be the case as inlined `Place`s are copied
@@ -1707,11 +1707,7 @@ pub struct Static<'tcx> {
     RustcEncodable,
     RustcDecodable
 )]
-pub enum StaticKind<'tcx> {
-    /// Promoted references consist of an id (`Promoted`) and the substs necessary to monomorphize
-    /// it. Usually, these substs are just the identity substs for the item. However, the inliner
-    /// will adjust these substs when it inlines a function based on the substs at the callsite.
-    Promoted(Promoted, SubstsRef<'tcx>),
+pub enum StaticKind {
     Static,
 }
 
@@ -1949,11 +1945,6 @@ impl Debug for PlaceBase<'_> {
             PlaceBase::Static(box self::Static { ty, kind: StaticKind::Static, def_id }) => {
                 write!(fmt, "({}: {:?})", ty::tls::with(|tcx| tcx.def_path_str(def_id)), ty)
             }
-            PlaceBase::Static(box self::Static {
-                ty,
-                kind: StaticKind::Promoted(promoted, _),
-                def_id: _,
-            }) => write!(fmt, "({:?}: {:?})", promoted, ty),
         }
     }
 }
@@ -3069,21 +3060,15 @@ impl<'tcx> TypeFoldable<'tcx> for Static<'tcx> {
     }
 }
 
-impl<'tcx> TypeFoldable<'tcx> for StaticKind<'tcx> {
-    fn super_fold_with<F: TypeFolder<'tcx>>(&self, folder: &mut F) -> Self {
+impl<'tcx> TypeFoldable<'tcx> for StaticKind {
+    fn super_fold_with<F: TypeFolder<'tcx>>(&self, _folder: &mut F) -> Self {
         match self {
-            StaticKind::Promoted(promoted, substs) => {
-                StaticKind::Promoted(promoted.fold_with(folder), substs.fold_with(folder))
-            }
             StaticKind::Static => StaticKind::Static,
         }
     }
 
-    fn super_visit_with<V: TypeVisitor<'tcx>>(&self, visitor: &mut V) -> bool {
+    fn super_visit_with<V: TypeVisitor<'tcx>>(&self, _visitor: &mut V) -> bool {
         match self {
-            StaticKind::Promoted(promoted, substs) => {
-                promoted.visit_with(visitor) || substs.visit_with(visitor)
-            }
             StaticKind::Static => false,
         }
     }

src/librustc_codegen_ssa/mir/block.rs

@@ -10,8 +10,8 @@ use crate::traits::*;
 use crate::MemFlags;
 
 use rustc::middle::lang_items;
+use rustc::mir;
 use rustc::mir::interpret::PanicInfo;
-use rustc::mir::{self, PlaceBase, Static, StaticKind};
 use rustc::ty::layout::{self, FnAbiExt, HasTyCtxt, LayoutOf};
 use rustc::ty::{self, Instance, Ty, TypeFoldable};
 use rustc_index::vec::Idx;
@@ -613,35 +613,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                             // The shuffle array argument is usually not an explicit constant,
                             // but specified directly in the code. This means it gets promoted
                             // and we can then extract the value by evaluating the promoted.
-                            mir::Operand::Copy(place) | mir::Operand::Move(place) => {
-                                if let mir::PlaceRef {
-                                    base:
-                                        &PlaceBase::Static(box Static {
-                                            kind: StaticKind::Promoted(promoted, substs),
-                                            ty,
-                                            def_id,
-                                        }),
-                                    projection: &[],
-                                } = place.as_ref()
-                                {
-                                    let c = bx.tcx().const_eval_promoted(
-                                        Instance::new(def_id, self.monomorphize(&substs)),
-                                        promoted,
-                                    );
-                                    let (llval, ty) = self.simd_shuffle_indices(
-                                        &bx,
-                                        terminator.source_info.span,
-                                        ty,
-                                        c,
-                                    );
-                                    return OperandRef {
-                                        val: Immediate(llval),
-                                        layout: bx.layout_of(ty),
-                                    };
-                                } else {
-                                    span_bug!(span, "shuffle indices must be constant");
-                                }
-                            }
+                            mir::Operand::Copy(_place) | mir::Operand::Move(_place) => {}
 
                             mir::Operand::Constant(constant) => {
                                 let c = self.eval_mir_constant(constant);

src/librustc_codegen_ssa/mir/place.rs

@@ -9,7 +9,7 @@ use crate::MemFlags;
 use rustc::mir;
 use rustc::mir::tcx::PlaceTy;
 use rustc::ty::layout::{self, Align, HasTyCtxt, LayoutOf, TyLayout, VariantIdx};
-use rustc::ty::{self, Instance, Ty};
+use rustc::ty::{self, Ty};
 
 #[derive(Copy, Clone, Debug)]
 pub struct PlaceRef<'tcx, V> {
@@ -437,39 +437,6 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                     }
                 }
             }
-            mir::PlaceRef {
-                base:
-                    mir::PlaceBase::Static(box mir::Static {
-                        ty,
-                        kind: mir::StaticKind::Promoted(promoted, substs),
-                        def_id,
-                    }),
-                projection: [],
-            } => {
-                let instance = Instance::new(*def_id, self.monomorphize(substs));
-                let layout = cx.layout_of(self.monomorphize(&ty));
-                match bx.tcx().const_eval_promoted(instance, *promoted) {
-                    Ok(val) => match val.val {
-                        ty::ConstKind::Value(mir::interpret::ConstValue::ByRef {
-                            alloc,
-                            offset,
-                        }) => bx.cx().from_const_alloc(layout, alloc, offset),
-                        _ => bug!("promoteds should have an allocation: {:?}", val),
-                    },
-                    Err(_) => {
-                        // This is unreachable as long as runtime
-                        // and compile-time agree perfectly.
-                        // With floats that won't always be true,
-                        // so we generate a (safe) abort.
-                        bx.abort();
-                        // We still have to return a place but it doesn't matter,
-                        // this code is unreachable.
-                        let llval =
-                            bx.cx().const_undef(bx.cx().type_ptr_to(bx.cx().backend_type(layout)));
-                        PlaceRef::new_sized(llval, layout)
-                    }
-                }
-            }
             mir::PlaceRef {
                 base:
                     mir::PlaceBase::Static(box mir::Static {

src/librustc_mir/borrow_check/diagnostics/mod.rs

@@ -172,12 +172,6 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             PlaceRef { base: PlaceBase::Local(local), projection: [] } => {
                 self.append_local_to_string(*local, buf)?;
             }
-            PlaceRef {
-                base: PlaceBase::Static(box Static { kind: StaticKind::Promoted(..), .. }),
-                projection: [],
-            } => {
-                buf.push_str("promoted");
-            }
             PlaceRef {
                 base: PlaceBase::Static(box Static { kind: StaticKind::Static, def_id, .. }),
                 projection: [],

src/librustc_mir/borrow_check/mod.rs

@@ -2196,16 +2196,6 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                     }),
                 }
             }
-            // The rules for promotion are made by `qualify_consts`, there wouldn't even be a
-            // `Place::Promoted` if the promotion weren't 100% legal. So we just forward this
-            PlaceRef {
-                base: PlaceBase::Static(box Static { kind: StaticKind::Promoted(..), .. }),
-                projection: [],
-            } => Ok(RootPlace {
-                place_base: place.base,
-                place_projection: place.projection,
-                is_local_mutation_allowed,
-            }),
             PlaceRef {
                 base: PlaceBase::Static(box Static { kind: StaticKind::Static, def_id, .. }),
                 projection: [],

src/librustc_mir/borrow_check/places_conflict.rs

@@ -310,7 +310,7 @@ fn place_components_conflict<'tcx>(
 // between `elem1` and `elem2`.
 fn place_base_conflict<'tcx>(
     tcx: TyCtxt<'tcx>,
-    param_env: ty::ParamEnv<'tcx>,
+    _param_env: ty::ParamEnv<'tcx>,
     elem1: &PlaceBase<'tcx>,
     elem2: &PlaceBase<'tcx>,
 ) -> Overlap {
@@ -341,28 +341,6 @@ fn place_base_conflict<'tcx>(
                         Overlap::EqualOrDisjoint
                     }
                 }
-                (StaticKind::Promoted(promoted_1, _), StaticKind::Promoted(promoted_2, _)) => {
-                    if promoted_1 == promoted_2 {
-                        if let ty::Array(_, len) = s1.ty.kind {
-                            if let Some(0) = len.try_eval_usize(tcx, param_env) {
-                                // Ignore conflicts with promoted [T; 0].
-                                debug!("place_element_conflict: IGNORE-LEN-0-PROMOTED");
-                                return Overlap::Disjoint;
-                            }
-                        }
-                        // the same promoted - base case, equal
-                        debug!("place_element_conflict: DISJOINT-OR-EQ-PROMOTED");
-                        Overlap::EqualOrDisjoint
-                    } else {
-                        // different promoteds - base case, disjoint
-                        debug!("place_element_conflict: DISJOINT-PROMOTED");
-                        Overlap::Disjoint
-                    }
-                }
-                (_, _) => {
-                    debug!("place_element_conflict: DISJOINT-STATIC-PROMOTED");
-                    Overlap::Disjoint
-                }
             }
         }
         (PlaceBase::Local(_), PlaceBase::Static(_))

src/librustc_mir/borrow_check/type_check/mod.rs

@@ -488,15 +488,6 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> {
                         };
                     };
                 match kind {
-                    StaticKind::Promoted(promoted, _) => {
-                        if !self.errors_reported {
-                            let promoted_body_cache = self.promoted[*promoted];
-                            self.sanitize_promoted(promoted_body_cache, location);
-
-                            let promoted_ty = promoted_body_cache.return_ty();
-                            check_err(self, place, promoted_ty, san_ty);
-                        }
-                    }
                     StaticKind::Static => {
                         let ty = self.tcx().type_of(*def_id);
                         let ty = self.cx.normalize(ty, location);
@@ -510,38 +501,28 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> {
 
         if place.projection.is_empty() {
             if let PlaceContext::NonMutatingUse(NonMutatingUseContext::Copy) = context {
-                let is_promoted = match place.as_ref() {
-                    PlaceRef {
-                        base: &PlaceBase::Static(box Static { kind: StaticKind::Promoted(..), .. }),
-                        projection: &[],
-                    } => true,
-                    _ => false,
+                let tcx = self.tcx();
+                let trait_ref = ty::TraitRef {
+                    def_id: tcx.lang_items().copy_trait().unwrap(),
+                    substs: tcx.mk_substs_trait(place_ty.ty, &[]),
                 };
 
-                if !is_promoted {
-                    let tcx = self.tcx();
-                    let trait_ref = ty::TraitRef {
-                        def_id: tcx.lang_items().copy_trait().unwrap(),
-                        substs: tcx.mk_substs_trait(place_ty.ty, &[]),
-                    };
-
-                    // To have a `Copy` operand, the type `T` of the
-                    // value must be `Copy`. Note that we prove that `T: Copy`,
-                    // rather than using the `is_copy_modulo_regions`
-                    // test. This is important because
-                    // `is_copy_modulo_regions` ignores the resulting region
-                    // obligations and assumes they pass. This can result in
-                    // bounds from `Copy` impls being unsoundly ignored (e.g.,
-                    // #29149). Note that we decide to use `Copy` before knowing
-                    // whether the bounds fully apply: in effect, the rule is
-                    // that if a value of some type could implement `Copy`, then
-                    // it must.
-                    self.cx.prove_trait_ref(
-                        trait_ref,
-                        location.to_locations(),
-                        ConstraintCategory::CopyBound,
-                    );
-                }
+                // To have a `Copy` operand, the type `T` of the
+                // value must be `Copy`. Note that we prove that `T: Copy`,
+                // rather than using the `is_copy_modulo_regions`
+                // test. This is important because
+                // `is_copy_modulo_regions` ignores the resulting region
+                // obligations and assumes they pass. This can result in
+                // bounds from `Copy` impls being unsoundly ignored (e.g.,
+                // #29149). Note that we decide to use `Copy` before knowing
+                // whether the bounds fully apply: in effect, the rule is
+                // that if a value of some type could implement `Copy`, then
+                // it must.
+                self.cx.prove_trait_ref(
+                    trait_ref,
+                    location.to_locations(),
+                    ConstraintCategory::CopyBound,
+                );
             }
         }
 

src/librustc_mir/interpret/place.rs

@@ -15,9 +15,9 @@ use rustc::ty::{self, Ty};
 use rustc_macros::HashStable;
 
 use super::{
-    AllocId, AllocMap, Allocation, AllocationExtra, GlobalId, ImmTy, Immediate, InterpCx,
-    InterpResult, LocalValue, Machine, MemoryKind, OpTy, Operand, Pointer, PointerArithmetic,
-    RawConst, Scalar, ScalarMaybeUndef,
+    AllocId, AllocMap, Allocation, AllocationExtra, ImmTy, Immediate, InterpCx, InterpResult,
+    LocalValue, Machine, MemoryKind, OpTy, Operand, Pointer, PointerArithmetic, RawConst, Scalar,
+    ScalarMaybeUndef,
 };
 
 #[derive(Copy, Clone, Debug, Hash, PartialEq, Eq, HashStable)]
@@ -628,19 +628,6 @@ where
         use rustc::mir::StaticKind;
 
         Ok(match place_static.kind {
-            StaticKind::Promoted(promoted, promoted_substs) => {
-                let substs = self.subst_from_frame_and_normalize_erasing_regions(promoted_substs);
-                let instance = ty::Instance::new(place_static.def_id, substs);
-
-                // Even after getting `substs` from the frame, this instance may still be
-                // polymorphic because `ConstProp` will try to promote polymorphic MIR.
-                if instance.needs_subst() {
-                    throw_inval!(TooGeneric);
-                }
-
-                self.const_eval_raw(GlobalId { instance, promoted: Some(promoted) })?
-            }
-
             StaticKind::Static => {
                 let ty = place_static.ty;
                 assert!(!ty.needs_subst());

src/librustc_mir/monomorphize/collector.rs

@@ -186,7 +186,7 @@ use rustc::mir::{self, Location, PlaceBase, Static, StaticKind};
 use rustc::session::config::EntryFnType;
 use rustc::ty::adjustment::{CustomCoerceUnsized, PointerCast};
 use rustc::ty::print::obsolete::DefPathBasedNames;
-use rustc::ty::subst::{InternalSubsts, Subst, SubstsRef};
+use rustc::ty::subst::{InternalSubsts, SubstsRef};
 use rustc::ty::{self, GenericParamDefKind, Instance, Ty, TyCtxt, TypeFoldable};
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_data_structures::sync::{par_iter, MTLock, MTRef, ParallelIterator};
@@ -656,21 +656,6 @@ impl<'a, 'tcx> MirVisitor<'tcx> for MirNeighborCollector<'a, 'tcx> {
                     self.output.push(MonoItem::Static(*def_id));
                 }
             }
-            PlaceBase::Static(box Static {
-                kind: StaticKind::Promoted(promoted, substs),
-                def_id,
-                ..
-            }) => {
-                let instance = Instance::new(*def_id, substs.subst(self.tcx, self.param_substs));
-                match self.tcx.const_eval_promoted(instance, *promoted) {
-                    Ok(val) => collect_const(self.tcx, val, substs, self.output),
-                    Err(ErrorHandled::Reported) => {}
-                    Err(ErrorHandled::TooGeneric) => {
-                        let span = self.tcx.promoted_mir(*def_id)[*promoted].span;
-                        span_bug!(span, "collection encountered polymorphic constant")
-                    }
-                }
-            }
             PlaceBase::Local(_) => {
                 // Locals have no relevance for collector.
             }

src/librustc_mir/transform/check_unsafety.rs

@@ -194,9 +194,6 @@ impl<'a, 'tcx> Visitor<'tcx> for UnsafetyChecker<'a, 'tcx> {
             PlaceBase::Local(..) => {
                 // Locals are safe.
             }
-            PlaceBase::Static(box Static { kind: StaticKind::Promoted(_, _), .. }) => {
-                bug!("unsafety checking should happen before promotion");
-            }
             PlaceBase::Static(box Static { kind: StaticKind::Static, .. }) => {
                 bug!("StaticKind::Static should not exist");
             }