Add `unwrap_usize` to `LazyConst`, too

21 files changed, 31 insertions, 34 deletions

diff --git a/src/librustc/mir/tcx.rs b/src/librustc/mir/tcx.rs
index 6dda1933bba..c5b884525da 100644
--- a/src/librustc/mir/tcx.rs
+++ b/src/librustc/mir/tcx.rs
@@ -114,7 +114,7 @@ impl<'a, 'gcx, 'tcx> PlaceTy<'tcx> {
                 PlaceTy::Ty {
                     ty: match ty.sty {
                         ty::Array(inner, size) => {
-                            let size = size.unwrap_evaluated().unwrap_usize(tcx);
+                            let size = size.unwrap_usize(tcx);
                             let len = size - (from as u64) - (to as u64);
                             tcx.mk_array(inner, len)
                         }
diff --git a/src/librustc/ty/layout.rs b/src/librustc/ty/layout.rs
index 1f25925a8e1..171c53b7b20 100644
--- a/src/librustc/ty/layout.rs
+++ b/src/librustc/ty/layout.rs
@@ -543,7 +543,7 @@ impl<'a, 'tcx> LayoutCx<'tcx, TyCtxt<'a, 'tcx, 'tcx>> {
                 }
 
                 let element = self.layout_of(element)?;
-                let count = count.unwrap_evaluated().unwrap_usize(tcx);
+                let count = count.unwrap_usize(tcx);
                 let size = element.size.checked_mul(count, dl)
                     .ok_or(LayoutError::SizeOverflow(ty))?;
 
diff --git a/src/librustc/ty/sty.rs b/src/librustc/ty/sty.rs
index 4a254fc1cd9..6fd3fbd7376 100644
--- a/src/librustc/ty/sty.rs
+++ b/src/librustc/ty/sty.rs
@@ -2024,13 +2024,6 @@ pub enum LazyConst<'tcx> {
 static_assert!(MEM_SIZE_OF_LAZY_CONST: ::std::mem::size_of::<LazyConst<'_>>() <= 24);
 
 impl<'tcx> LazyConst<'tcx> {
-    pub fn unwrap_evaluated(self) -> &'tcx Const<'tcx> {
-        match self {
-            LazyConst::Evaluated(c) => c,
-            LazyConst::Unevaluated(..) => bug!("unexpected unevaluated constant"),
-        }
-    }
-
     pub fn map_evaluated<R>(self, f: impl FnOnce(&'tcx Const<'tcx>) -> Option<R>) -> Option<R> {
         match self {
             LazyConst::Evaluated(c) => f(c),
@@ -2038,9 +2031,14 @@ impl<'tcx> LazyConst<'tcx> {
         }
     }
 
-    pub fn assert_usize(self, tcx: TyCtxt<'_, '_, 'tcx>) -> Option<u64> {
+    pub fn assert_usize(self, tcx: TyCtxt<'_, '_, '_>) -> Option<u64> {
         self.map_evaluated(|c| c.assert_usize(tcx))
     }
+
+    #[inline]
+    pub fn unwrap_usize(&self, tcx: TyCtxt<'_, '_, '_>) -> u64 {
+        self.assert_usize(tcx).expect("expected `LazyConst` to contain a usize")
+    }
 }
 
 /// Typed constant value.
diff --git a/src/librustc_codegen_llvm/debuginfo/metadata.rs b/src/librustc_codegen_llvm/debuginfo/metadata.rs
index bec0cfa0d86..0fd04e9d203 100644
--- a/src/librustc_codegen_llvm/debuginfo/metadata.rs
+++ b/src/librustc_codegen_llvm/debuginfo/metadata.rs
@@ -302,7 +302,7 @@ fn fixed_vec_metadata(
 
     let upper_bound = match array_or_slice_type.sty {
         ty::Array(_, len) => {
-            len.unwrap_evaluated().unwrap_usize(cx.tcx) as c_longlong
+            len.unwrap_usize(cx.tcx) as c_longlong
         }
         _ => -1
     };
diff --git a/src/librustc_codegen_llvm/debuginfo/type_names.rs b/src/librustc_codegen_llvm/debuginfo/type_names.rs
index c1309569c79..c8cbd735e85 100644
--- a/src/librustc_codegen_llvm/debuginfo/type_names.rs
+++ b/src/librustc_codegen_llvm/debuginfo/type_names.rs
@@ -88,7 +88,7 @@ pub fn push_debuginfo_type_name<'a, 'tcx>(cx: &CodegenCx<'a, 'tcx>,
         ty::Array(inner_type, len) => {
             output.push('[');
             push_debuginfo_type_name(cx, inner_type, true, output);
-            output.push_str(&format!("; {}", len.unwrap_evaluated().unwrap_usize(cx.tcx)));
+            output.push_str(&format!("; {}", len.unwrap_usize(cx.tcx)));
             output.push(']');
         },
         ty::Slice(inner_type) => {
diff --git a/src/librustc_codegen_ssa/base.rs b/src/librustc_codegen_ssa/base.rs
index 166655f6a80..b88ec075653 100644
--- a/src/librustc_codegen_ssa/base.rs
+++ b/src/librustc_codegen_ssa/base.rs
@@ -171,7 +171,7 @@ pub fn unsized_info<'tcx, Cx: CodegenMethods<'tcx>>(
     let (source, target) = cx.tcx().struct_lockstep_tails(source, target);
     match (&source.sty, &target.sty) {
         (&ty::Array(_, len), &ty::Slice(_)) => {
-            cx.const_usize(len.unwrap_evaluated().unwrap_usize(cx.tcx()))
+            cx.const_usize(len.unwrap_usize(cx.tcx()))
         }
         (&ty::Dynamic(..), &ty::Dynamic(..)) => {
             // For now, upcasts are limited to changes in marker
diff --git a/src/librustc_codegen_ssa/mir/constant.rs b/src/librustc_codegen_ssa/mir/constant.rs
index 58325e34432..35bd3a32e81 100644
--- a/src/librustc_codegen_ssa/mir/constant.rs
+++ b/src/librustc_codegen_ssa/mir/constant.rs
@@ -52,7 +52,7 @@ impl<'a, 'tcx: 'a, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
             .and_then(|c| {
                 let field_ty = c.ty.builtin_index().unwrap();
                 let fields = match c.ty.sty {
-                    ty::Array(_, n) => n.unwrap_evaluated().unwrap_usize(bx.tcx()),
+                    ty::Array(_, n) => n.unwrap_usize(bx.tcx()),
                     ref other => bug!("invalid simd shuffle type: {}", other),
                 };
                 let values: Result<Vec<_>, ErrorHandled> = (0..fields).map(|field| {
diff --git a/src/librustc_codegen_ssa/mir/rvalue.rs b/src/librustc_codegen_ssa/mir/rvalue.rs
index 404ee86c6a1..9ca5414fa71 100644
--- a/src/librustc_codegen_ssa/mir/rvalue.rs
+++ b/src/librustc_codegen_ssa/mir/rvalue.rs
@@ -537,7 +537,7 @@ impl<'a, 'tcx: 'a, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
         if let mir::Place::Local(index) = *place {
             if let LocalRef::Operand(Some(op)) = self.locals[index] {
                 if let ty::Array(_, n) = op.layout.ty.sty {
-                    let n = n.unwrap_evaluated().unwrap_usize(bx.cx().tcx());
+                    let n = n.unwrap_usize(bx.cx().tcx());
                     return bx.cx().const_usize(n);
                 }
             }
diff --git a/src/librustc_mir/borrow_check/nll/type_check/mod.rs b/src/librustc_mir/borrow_check/nll/type_check/mod.rs
index 3681c3d74eb..c11eae7edee 100644
--- a/src/librustc_mir/borrow_check/nll/type_check/mod.rs
+++ b/src/librustc_mir/borrow_check/nll/type_check/mod.rs
@@ -568,7 +568,7 @@ impl<'a, 'b, 'gcx, 'tcx> TypeVerifier<'a, 'b, 'gcx, 'tcx> {
             ProjectionElem::Subslice { from, to } => PlaceTy::Ty {
                 ty: match base_ty.sty {
                     ty::Array(inner, size) => {
-                        let size = size.unwrap_evaluated().unwrap_usize(tcx);
+                        let size = size.unwrap_usize(tcx);
                         let min_size = (from as u64) + (to as u64);
                         if let Some(rest_size) = size.checked_sub(min_size) {
                             tcx.mk_array(inner, rest_size)
diff --git a/src/librustc_mir/borrow_check/places_conflict.rs b/src/librustc_mir/borrow_check/places_conflict.rs
index 88c27a869c0..ac7182abb36 100644
--- a/src/librustc_mir/borrow_check/places_conflict.rs
+++ b/src/librustc_mir/borrow_check/places_conflict.rs
@@ -388,7 +388,7 @@ fn place_element_conflict<'a, 'gcx: 'tcx, 'tcx>(
         (Place::Promoted(p1), Place::Promoted(p2)) => {
             if p1.0 == p2.0 {
                 if let ty::Array(_, size) = p1.1.sty {
-                    if size.unwrap_evaluated().unwrap_usize(tcx) == 0 {
+                    if size.unwrap_usize(tcx) == 0 {
                         // Ignore conflicts with promoted [T; 0].
                         debug!("place_element_conflict: IGNORE-LEN-0-PROMOTED");
                         return Overlap::Disjoint;
diff --git a/src/librustc_mir/hair/pattern/_match.rs b/src/librustc_mir/hair/pattern/_match.rs
index 176c2f65643..0f5510a2921 100644
--- a/src/librustc_mir/hair/pattern/_match.rs
+++ b/src/librustc_mir/hair/pattern/_match.rs
@@ -635,7 +635,7 @@ fn all_constructors<'a, 'tcx: 'a>(cx: &mut MatchCheckCtxt<'a, 'tcx>,
             }).collect()
         }
         ty::Array(ref sub_ty, len) if len.assert_usize(cx.tcx).is_some() => {
-            let len = len.unwrap_evaluated().unwrap_usize(cx.tcx);
+            let len = len.unwrap_usize(cx.tcx);
             if len != 0 && cx.is_uninhabited(sub_ty) {
                 vec![]
             } else {
@@ -1310,7 +1310,7 @@ fn pat_constructors<'tcx>(cx: &mut MatchCheckCtxt<'_, 'tcx>,
             )]),
         PatternKind::Array { .. } => match pcx.ty.sty {
             ty::Array(_, length) => Some(vec![
-                Slice(length.unwrap_evaluated().unwrap_usize(cx.tcx))
+                Slice(length.unwrap_usize(cx.tcx))
             ]),
             _ => span_bug!(pat.span, "bad ty {:?} for array pattern", pcx.ty)
         },
@@ -1753,7 +1753,7 @@ fn specialize<'p, 'a: 'p, 'tcx: 'a>(
                     // slices
                     let (opt_ptr, n, ty) = match value.ty.builtin_deref(false).unwrap().ty.sty {
                         ty::TyKind::Array(t, n) =>
-                            (value.to_ptr(), n.unwrap_evaluated().unwrap_usize(cx.tcx), t),
+                            (value.to_ptr(), n.unwrap_usize(cx.tcx), t),
                         ty::TyKind::Slice(t) => {
                             match value.val {
                                 ConstValue::ScalarPair(ptr, n) => (
diff --git a/src/librustc_mir/hair/pattern/mod.rs b/src/librustc_mir/hair/pattern/mod.rs
index d7eeaf43651..10d2d7bc1b1 100644
--- a/src/librustc_mir/hair/pattern/mod.rs
+++ b/src/librustc_mir/hair/pattern/mod.rs
@@ -650,7 +650,7 @@ impl<'a, 'tcx> PatternContext<'a, 'tcx> {
 
             ty::Array(_, len) => {
                 // fixed-length array
-                let len = len.unwrap_evaluated().unwrap_usize(self.tcx);
+                let len = len.unwrap_usize(self.tcx);
                 assert!(len >= prefix.len() as u64 + suffix.len() as u64);
                 PatternKind::Array { prefix: prefix, slice: slice, suffix: suffix }
             }
@@ -934,7 +934,7 @@ impl<'a, 'tcx> PatternContext<'a, 'tcx> {
             }
             ty::Array(_, n) => {
                 PatternKind::Array {
-                    prefix: (0..n.unwrap_evaluated().unwrap_usize(self.tcx))
+                    prefix: (0..n.unwrap_usize(self.tcx))
                         .map(|i| adt_subpattern(i as usize, None))
                         .collect(),
                     slice: None,
diff --git a/src/librustc_mir/interpret/cast.rs b/src/librustc_mir/interpret/cast.rs
index 37c5340e0a2..190a381cf52 100644
--- a/src/librustc_mir/interpret/cast.rs
+++ b/src/librustc_mir/interpret/cast.rs
@@ -307,7 +307,7 @@ impl<'a, 'mir, 'tcx, M: Machine<'a, 'mir, 'tcx>> EvalContext<'a, 'mir, 'tcx, M>
                 // u64 cast is from usize to u64, which is always good
                 let val = Immediate::new_slice(
                     ptr,
-                    length.unwrap_evaluated().unwrap_usize(self.tcx.tcx),
+                    length.unwrap_usize(self.tcx.tcx),
                     self,
                 );
                 self.write_immediate(val, dest)
diff --git a/src/librustc_mir/monomorphize/item.rs b/src/librustc_mir/monomorphize/item.rs
index 8cd8eb3ad64..e7f4451fdd7 100644
--- a/src/librustc_mir/monomorphize/item.rs
+++ b/src/librustc_mir/monomorphize/item.rs
@@ -295,7 +295,7 @@ impl<'a, 'tcx> DefPathBasedNames<'a, 'tcx> {
             ty::Array(inner_type, len) => {
                 output.push('[');
                 self.push_type_name(inner_type, output);
-                write!(output, "; {}", len.unwrap_evaluated().unwrap_usize(self.tcx)).unwrap();
+                write!(output, "; {}", len.unwrap_usize(self.tcx)).unwrap();
                 output.push(']');
             },
             ty::Slice(inner_type) => {
diff --git a/src/librustc_mir/shim.rs b/src/librustc_mir/shim.rs
index 835a5dede74..73e26d63493 100644
--- a/src/librustc_mir/shim.rs
+++ b/src/librustc_mir/shim.rs
@@ -318,7 +318,7 @@ fn build_clone_shim<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
     match self_ty.sty {
         _ if is_copy => builder.copy_shim(),
         ty::Array(ty, len) => {
-            let len = len.unwrap_evaluated().unwrap_usize(tcx);
+            let len = len.unwrap_usize(tcx);
             builder.array_shim(dest, src, ty, len)
         }
         ty::Closure(def_id, substs) => {
diff --git a/src/librustc_mir/transform/qualify_consts.rs b/src/librustc_mir/transform/qualify_consts.rs
index 209c26a0c6c..f35685b7b0c 100644
--- a/src/librustc_mir/transform/qualify_consts.rs
+++ b/src/librustc_mir/transform/qualify_consts.rs
@@ -712,7 +712,7 @@ impl<'a, 'tcx> Visitor<'tcx> for Qualifier<'a, 'tcx, 'tcx> {
                     } else if let ty::Array(_, len) = ty.sty {
                         // FIXME(eddyb) the `self.mode == Mode::Fn` condition
                         // seems unnecessary, given that this is merely a ZST.
-                        let len = len.unwrap_evaluated().unwrap_usize(self.tcx);
+                        let len = len.unwrap_usize(self.tcx);
                         if len == 0 && self.mode == Mode::Fn {
                             forbidden_mut = false;
                         }
diff --git a/src/librustc_mir/transform/simplify_branches.rs b/src/librustc_mir/transform/simplify_branches.rs
index 1d5bc4f9cc3..60a569e297d 100644
--- a/src/librustc_mir/transform/simplify_branches.rs
+++ b/src/librustc_mir/transform/simplify_branches.rs
@@ -51,9 +51,8 @@ impl MirPass for SimplifyBranches {
                 },
                 TerminatorKind::Assert {
                     target, cond: Operand::Constant(ref c), expected, ..
-                } if (c.literal.unwrap_evaluated().assert_bool(tcx) == Some(true)) == expected => {
-                    TerminatorKind::Goto { target }
-                },
+                } if (c.literal.map_evaluated(|e| e.assert_bool(tcx)) == Some(true)) == expected =>
+                    TerminatorKind::Goto { target },
                 TerminatorKind::FalseEdges { real_target, .. } => {
                     TerminatorKind::Goto { target: real_target }
                 },
diff --git a/src/librustc_mir/transform/uniform_array_move_out.rs b/src/librustc_mir/transform/uniform_array_move_out.rs
index 172993daa9a..5ab9669baac 100644
--- a/src/librustc_mir/transform/uniform_array_move_out.rs
+++ b/src/librustc_mir/transform/uniform_array_move_out.rs
@@ -71,7 +71,7 @@ impl<'a, 'tcx> Visitor<'tcx> for UniformArrayMoveOutVisitor<'a, 'tcx> {
                 } else {
                     let place_ty = proj.base.ty(self.mir, self.tcx).to_ty(self.tcx);
                     if let ty::Array(item_ty, const_size) = place_ty.sty {
-                        if let Some(size) = const_size.unwrap_evaluated().assert_usize(self.tcx) {
+                        if let Some(size) = const_size.assert_usize(self.tcx) {
                             assert!(size <= u32::max_value() as u64,
                                     "uniform array move out doesn't supported
                                      for array bigger then u32");
@@ -193,7 +193,7 @@ impl MirPass for RestoreSubsliceArrayMoveOut {
                         let opt_size = opt_src_place.and_then(|src_place| {
                             let src_ty = src_place.ty(mir, tcx).to_ty(tcx);
                             if let ty::Array(_, ref size_o) = src_ty.sty {
-                                size_o.unwrap_evaluated().assert_usize(tcx)
+                                size_o.assert_usize(tcx)
                             } else {
                                 None
                             }
diff --git a/src/librustc_mir/util/elaborate_drops.rs b/src/librustc_mir/util/elaborate_drops.rs
index 221c2d55eec..8b55a4424ae 100644
--- a/src/librustc_mir/util/elaborate_drops.rs
+++ b/src/librustc_mir/util/elaborate_drops.rs
@@ -809,7 +809,7 @@ impl<'l, 'b, 'tcx, D> DropCtxt<'l, 'b, 'tcx, D>
                 self.complete_drop(Some(DropFlagMode::Deep), succ, unwind)
             }
             ty::Array(ety, size) => {
-                let size = size.unwrap_evaluated().assert_usize(self.tcx());
+                let size = size.assert_usize(self.tcx());
                 self.open_drop_for_array(ety, size)
             },
             ty::Slice(ety) => self.open_drop_for_array(ety, None),
diff --git a/src/librustc_typeck/check/_match.rs b/src/librustc_typeck/check/_match.rs
index 13311a2efd5..b66c383edb5 100644
--- a/src/librustc_typeck/check/_match.rs
+++ b/src/librustc_typeck/check/_match.rs
@@ -377,7 +377,7 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
                 let expected_ty = self.structurally_resolved_type(pat.span, expected);
                 let (inner_ty, slice_ty) = match expected_ty.sty {
                     ty::Array(inner_ty, size) => {
-                        let size = size.unwrap_evaluated().unwrap_usize(tcx);
+                        let size = size.unwrap_usize(tcx);
                         let min_len = before.len() as u64 + after.len() as u64;
                         if slice.is_none() {
                             if min_len != size {
diff --git a/src/librustc_typeck/check/mod.rs b/src/librustc_typeck/check/mod.rs
index d664eed0a34..4865b70687d 100644
--- a/src/librustc_typeck/check/mod.rs
+++ b/src/librustc_typeck/check/mod.rs
@@ -3453,7 +3453,7 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
                     }
                     ty::Array(_, len) => {
                         if let (Some(len), Ok(user_index)) = (
-                            len.unwrap_evaluated().assert_usize(self.tcx),
+                            len.assert_usize(self.tcx),
                             field.as_str().parse::<u64>()
                         ) {
                             let base = self.tcx.sess.source_map()