Auto merge of #75893 - Dylan-DPC:fix/offset-to-u64, r=oli-obk

change offset from u32 to u64

References #71696

r? @oli-obk

(closed the earlier pr because the rebase got messed up)

Author: bors

src/librustc_middle/mir/mod.rs

@@ -1564,10 +1564,10 @@ pub enum ProjectionElem<V, T> {
     /// ```
     ConstantIndex {
         /// index or -index (in Python terms), depending on from_end
-        offset: u32,
+        offset: u64,
         /// The thing being indexed must be at least this long. For arrays this
         /// is always the exact length.
-        min_length: u32,
+        min_length: u64,
         /// Counting backwards from end? This is always false when indexing an
         /// array.
         from_end: bool,
@@ -1578,8 +1578,8 @@ pub enum ProjectionElem<V, T> {
     /// If `from_end` is true `slice[from..slice.len() - to]`.
     /// Otherwise `array[from..to]`.
     Subslice {
-        from: u32,
-        to: u32,
+        from: u64,
+        to: u64,
         /// Whether `to` counts from the start or end of the array/slice.
         /// For `PlaceElem`s this is `true` if and only if the base is a slice.
         /// For `ProjectionKind`, this can also be `true` for arrays.
@@ -1616,7 +1616,7 @@ pub type PlaceElem<'tcx> = ProjectionElem<Local, Ty<'tcx>>;
 
 // At least on 64 bit systems, `PlaceElem` should not be larger than two pointers.
 #[cfg(target_arch = "x86_64")]
-static_assert_size!(PlaceElem<'_>, 16);
+static_assert_size!(PlaceElem<'_>, 24);
 
 /// Alias for projections as they appear in `UserTypeProjection`, where we
 /// need neither the `V` parameter for `Index` nor the `T` for `Field`.
@@ -2330,7 +2330,7 @@ impl<'tcx> UserTypeProjections {
         self.map_projections(|pat_ty_proj| pat_ty_proj.index())
     }
 
-    pub fn subslice(self, from: u32, to: u32) -> Self {
+    pub fn subslice(self, from: u64, to: u64) -> Self {
         self.map_projections(|pat_ty_proj| pat_ty_proj.subslice(from, to))
     }
 
@@ -2376,7 +2376,7 @@ impl UserTypeProjection {
         self
     }
 
-    pub(crate) fn subslice(mut self, from: u32, to: u32) -> Self {
+    pub(crate) fn subslice(mut self, from: u64, to: u64) -> Self {
         self.projs.push(ProjectionElem::Subslice { from, to, from_end: true });
         self
     }

src/librustc_mir/borrow_check/mod.rs

@@ -1694,8 +1694,8 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         desired_action: InitializationRequiringAction,
         place_span: (PlaceRef<'tcx>, Span),
         maybe_uninits: &BitSet<MovePathIndex>,
-        from: u32,
-        to: u32,
+        from: u64,
+        to: u64,
     ) {
         if let Some(mpi) = self.move_path_for_place(place_span.0) {
             let move_paths = &self.move_data.move_paths;

src/librustc_mir/borrow_check/type_check/mod.rs

@@ -649,7 +649,7 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> {
                 PlaceTy::from_ty(match base_ty.kind {
                     ty::Array(inner, _) => {
                         assert!(!from_end, "array subslices should not use from_end");
-                        tcx.mk_array(inner, (to - from) as u64)
+                        tcx.mk_array(inner, to - from)
                     }
                     ty::Slice(..) => {
                         assert!(from_end, "slice subslices should use from_end");

src/librustc_mir/dataflow/move_paths/builder.rs

@@ -480,7 +480,7 @@ impl<'b, 'a, 'tcx> Gatherer<'b, 'a, 'tcx> {
                 }
             };
             let base_ty = base_place.ty(self.builder.body, self.builder.tcx).ty;
-            let len: u32 = match base_ty.kind {
+            let len: u64 = match base_ty.kind {
                 ty::Array(_, size) => {
                     let length = size.eval_usize(self.builder.tcx, self.builder.param_env);
                     length

src/librustc_mir/interpret/place.rs

@@ -549,17 +549,17 @@ where
 
             ConstantIndex { offset, min_length, from_end } => {
                 let n = base.len(self)?;
-                if n < u64::from(min_length) {
+                if n < min_length {
                     // This can only be reached in ConstProp and non-rustc-MIR.
                     throw_ub!(BoundsCheckFailed { len: min_length.into(), index: n });
                 }
 
                 let index = if from_end {
                     assert!(0 < offset && offset <= min_length);
-                    n.checked_sub(u64::from(offset)).unwrap()
+                    n.checked_sub(offset).unwrap()
                 } else {
                     assert!(offset < min_length);
-                    u64::from(offset)
+                    offset
                 };
 
                 self.mplace_index(base, index)?

src/librustc_mir/shim.rs

@@ -295,7 +295,7 @@ impl<'a, 'tcx> DropElaborator<'a, 'tcx> for DropShimElaborator<'a, 'tcx> {
     fn downcast_subpath(&self, _path: Self::Path, _variant: VariantIdx) -> Option<Self::Path> {
         Some(())
     }
-    fn array_subpath(&self, _path: Self::Path, _index: u32, _size: u32) -> Option<Self::Path> {
+    fn array_subpath(&self, _path: Self::Path, _index: u64, _size: u64) -> Option<Self::Path> {
         None
     }
 }

src/librustc_mir/transform/elaborate_drops.rs

@@ -219,7 +219,7 @@ impl<'a, 'b, 'tcx> DropElaborator<'a, 'tcx> for Elaborator<'a, 'b, 'tcx> {
         })
     }
 
-    fn array_subpath(&self, path: Self::Path, index: u32, size: u32) -> Option<Self::Path> {
+    fn array_subpath(&self, path: Self::Path, index: u64, size: u64) -> Option<Self::Path> {
         dataflow::move_path_children_matching(self.ctxt.move_data(), path, |e| match e {
             ProjectionElem::ConstantIndex { offset, min_length, from_end } => {
                 debug_assert!(size == min_length, "min_length should be exact for arrays");

src/librustc_mir/util/aggregate.rs

@@ -3,6 +3,7 @@ use rustc_middle::mir::*;
 use rustc_middle::ty::{Ty, TyCtxt};
 use rustc_target::abi::VariantIdx;
 
+use std::convert::TryFrom;
 use std::iter::TrustedLen;
 
 /// Expand `lhs = Rvalue::Aggregate(kind, operands)` into assignments to the fields.
@@ -52,14 +53,11 @@ pub fn expand_aggregate<'tcx>(
         .enumerate()
         .map(move |(i, (op, ty))| {
             let lhs_field = if let AggregateKind::Array(_) = kind {
-                // FIXME(eddyb) `offset` should be u64.
-                let offset = i as u32;
-                assert_eq!(offset as usize, i);
+                let offset = u64::try_from(i).unwrap();
                 tcx.mk_place_elem(
                     lhs,
                     ProjectionElem::ConstantIndex {
                         offset,
-                        // FIXME(eddyb) `min_length` doesn't appear to be used.
                         min_length: offset + 1,
                         from_end: false,
                     },

src/librustc_mir/util/elaborate_drops.rs

@@ -10,8 +10,6 @@ use rustc_middle::ty::{self, Ty, TyCtxt};
 use rustc_target::abi::VariantIdx;
 use std::fmt;
 
-use std::convert::TryInto;
-
 /// The value of an inserted drop flag.
 #[derive(Debug, PartialEq, Eq, Copy, Clone)]
 pub enum DropFlagState {
@@ -150,7 +148,7 @@ pub trait DropElaborator<'a, 'tcx>: fmt::Debug {
     /// If this returns `None`, elements of `path` will not get a dedicated drop flag.
     ///
     /// This is only relevant for array patterns, which can move out of individual array elements.
-    fn array_subpath(&self, path: Self::Path, index: u32, size: u32) -> Option<Self::Path>;
+    fn array_subpath(&self, path: Self::Path, index: u64, size: u64) -> Option<Self::Path>;
 }
 
 #[derive(Debug)]
@@ -744,9 +742,6 @@ where
         let tcx = self.tcx();
 
         if let Some(size) = opt_size {
-            let size: u32 = size.try_into().unwrap_or_else(|_| {
-                bug!("move out check isn't implemented for array sizes bigger than u32::MAX");
-            });
             let fields: Vec<(Place<'tcx>, Option<D::Path>)> = (0..size)
                 .map(|i| {
                     (

src/librustc_mir_build/build/matches/mod.rs

@@ -609,8 +609,8 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
 
             PatKind::Array { ref prefix, ref slice, ref suffix }
             | PatKind::Slice { ref prefix, ref slice, ref suffix } => {
-                let from = u32::try_from(prefix.len()).unwrap();
-                let to = u32::try_from(suffix.len()).unwrap();
+                let from = u64::try_from(prefix.len()).unwrap();
+                let to = u64::try_from(suffix.len()).unwrap();
                 for subpattern in prefix {
                     self.visit_primary_bindings(subpattern, pattern_user_ty.clone().index(), f);
                 }

src/librustc_mir_build/build/matches/util.rs

@@ -40,17 +40,17 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
 
         match_pairs.extend(prefix.iter().enumerate().map(|(idx, subpattern)| {
             let elem =
-                ProjectionElem::ConstantIndex { offset: idx as u32, min_length, from_end: false };
+                ProjectionElem::ConstantIndex { offset: idx as u64, min_length, from_end: false };
             let place = tcx.mk_place_elem(*place, elem);
             MatchPair::new(place, subpattern)
         }));
 
         if let Some(subslice_pat) = opt_slice {
-            let suffix_len = suffix.len() as u32;
+            let suffix_len = suffix.len() as u64;
             let subslice = tcx.mk_place_elem(
                 *place,
                 ProjectionElem::Subslice {
-                    from: prefix.len() as u32,
+                    from: prefix.len() as u64,
                     to: if exact_size { min_length - suffix_len } else { suffix_len },
                     from_end: !exact_size,
                 },
@@ -59,7 +59,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
         }
 
         match_pairs.extend(suffix.iter().rev().enumerate().map(|(idx, subpattern)| {
-            let end_offset = (idx + 1) as u32;
+            let end_offset = (idx + 1) as u64;
             let elem = ProjectionElem::ConstantIndex {
                 offset: if exact_size { min_length - end_offset } else { end_offset },
                 min_length,