Show the values and computation that would overflow a const evaluation or propagation

src/librustc_codegen_ssa/mir/block.rs

@@ -380,7 +380,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
         // checked operation, just a comparison with the minimum
         // value, so we have to check for the assert message.
         if !bx.check_overflow() {
-            if let AssertKind::OverflowNeg = *msg {
+            if let AssertKind::OverflowNeg(_) = *msg {
                 const_cond = Some(expected);
             }
         }

src/librustc_middle/mir/mod.rs

@@ -2,6 +2,8 @@
 //!
 //! [rustc dev guide]: https://rustc-dev-guide.rust-lang.org/mir/index.html
 
+// ignore-tidy-filelength
+
 use crate::mir::interpret::{GlobalAlloc, Scalar};
 use crate::mir::visit::MirVisitable;
 use crate::ty::adjustment::PointerCast;
@@ -1246,10 +1248,10 @@ pub enum TerminatorKind<'tcx> {
 #[derive(Clone, RustcEncodable, RustcDecodable, HashStable, PartialEq)]
 pub enum AssertKind<O> {
     BoundsCheck { len: O, index: O },
-    Overflow(BinOp),
-    OverflowNeg,
-    DivisionByZero,
-    RemainderByZero,
+    Overflow(BinOp, O, O),
+    OverflowNeg(O),
+    DivisionByZero(O),
+    RemainderByZero(O),
     ResumedAfterReturn(GeneratorKind),
     ResumedAfterPanic(GeneratorKind),
 }
@@ -1522,17 +1524,17 @@ impl<O> AssertKind<O> {
     pub fn description(&self) -> &'static str {
         use AssertKind::*;
         match self {
-            Overflow(BinOp::Add) => "attempt to add with overflow",
-            Overflow(BinOp::Sub) => "attempt to subtract with overflow",
-            Overflow(BinOp::Mul) => "attempt to multiply with overflow",
-            Overflow(BinOp::Div) => "attempt to divide with overflow",
-            Overflow(BinOp::Rem) => "attempt to calculate the remainder with overflow",
-            OverflowNeg => "attempt to negate with overflow",
-            Overflow(BinOp::Shr) => "attempt to shift right with overflow",
-            Overflow(BinOp::Shl) => "attempt to shift left with overflow",
-            Overflow(op) => bug!("{:?} cannot overflow", op),
-            DivisionByZero => "attempt to divide by zero",
-            RemainderByZero => "attempt to calculate the remainder with a divisor of zero",
+            Overflow(BinOp::Add, _, _) => "attempt to add with overflow",
+            Overflow(BinOp::Sub, _, _) => "attempt to subtract with overflow",
+            Overflow(BinOp::Mul, _, _) => "attempt to multiply with overflow",
+            Overflow(BinOp::Div, _, _) => "attempt to divide with overflow",
+            Overflow(BinOp::Rem, _, _) => "attempt to calculate the remainder with overflow",
+            OverflowNeg(_) => "attempt to negate with overflow",
+            Overflow(BinOp::Shr, _, _) => "attempt to shift right with overflow",
+            Overflow(BinOp::Shl, _, _) => "attempt to shift left with overflow",
+            Overflow(op, _, _) => bug!("{:?} cannot overflow", op),
+            DivisionByZero(_) => "attempt to divide by zero",
+            RemainderByZero(_) => "attempt to calculate the remainder with a divisor of zero",
             ResumedAfterReturn(GeneratorKind::Gen) => "generator resumed after completion",
             ResumedAfterReturn(GeneratorKind::Async(_)) => "`async fn` resumed after completion",
             ResumedAfterPanic(GeneratorKind::Gen) => "generator resumed after panicking",
@@ -1546,12 +1548,54 @@ impl<O> AssertKind<O> {
     where
         O: Debug,
     {
+        use AssertKind::*;
         match self {
-            AssertKind::BoundsCheck { ref len, ref index } => write!(
+            BoundsCheck { ref len, ref index } => write!(
                 f,
                 "\"index out of bounds: the len is {{}} but the index is {{}}\", {:?}, {:?}",
                 len, index
             ),
+
+            OverflowNeg(op) => {
+                write!(f, "\"attempt to negate {{}} which would overflow\", {:?}", op)
+            }
+            DivisionByZero(op) => write!(f, "\"attempt to divide {{}} by zero\", {:?}", op),
+            RemainderByZero(op) => write!(
+                f,
+                "\"attempt to calculate the remainder of {{}} with a divisor of zero\", {:?}",
+                op
+            ),
+            Overflow(BinOp::Add, l, r) => write!(
+                f,
+                "\"attempt to compute `{{}} + {{}}` which would overflow\", {:?}, {:?}",
+                l, r
+            ),
+            Overflow(BinOp::Sub, l, r) => write!(
+                f,
+                "\"attempt to compute `{{}} - {{}}` which would overflow\", {:?}, {:?}",
+                l, r
+            ),
+            Overflow(BinOp::Mul, l, r) => write!(
+                f,
+                "\"attempt to compute `{{}} * {{}}` which would overflow\", {:?}, {:?}",
+                l, r
+            ),
+            Overflow(BinOp::Div, l, r) => write!(
+                f,
+                "\"attempt to compute `{{}} / {{}}` which would overflow\", {:?}, {:?}",
+                l, r
+            ),
+            Overflow(BinOp::Rem, l, r) => write!(
+                f,
+                "\"attempt to compute the remainder of `{{}} % {{}}` which would overflow\", {:?}, {:?}",
+                l, r
+            ),
+            Overflow(BinOp::Shr, _, r) => {
+                write!(f, "\"attempt to shift right by {{}} which would overflow\", {:?}", r)
+            }
+            Overflow(BinOp::Shl, _, r) => {
+                write!(f, "\"attempt to shift left by {{}} which would overflow\", {:?}", r)
+            }
             _ => write!(f, "\"{}\"", self.description()),
         }
     }
@@ -1564,6 +1608,34 @@ impl<O: fmt::Debug> fmt::Debug for AssertKind<O> {
             BoundsCheck { ref len, ref index } => {
                 write!(f, "index out of bounds: the len is {:?} but the index is {:?}", len, index)
             }
+            OverflowNeg(op) => write!(f, "attempt to negate {:#?} which would overflow", op),
+            DivisionByZero(op) => write!(f, "attempt to divide {:#?} by zero", op),
+            RemainderByZero(op) => {
+                write!(f, "attempt to calculate the remainder of {:#?} with a divisor of zero", op)
+            }
+            Overflow(BinOp::Add, l, r) => {
+                write!(f, "attempt to compute `{:#?} + {:#?}` which would overflow", l, r)
+            }
+            Overflow(BinOp::Sub, l, r) => {
+                write!(f, "attempt to compute `{:#?} - {:#?}` which would overflow", l, r)
+            }
+            Overflow(BinOp::Mul, l, r) => {
+                write!(f, "attempt to compute `{:#?} * {:#?}` which would overflow", l, r)
+            }
+            Overflow(BinOp::Div, l, r) => {
+                write!(f, "attempt to compute `{:#?} / {:#?}` which would overflow", l, r)
+            }
+            Overflow(BinOp::Rem, l, r) => write!(
+                f,
+                "attempt to compute the remainder of `{:#?} % {:#?}` which would overflow",
+                l, r
+            ),
+            Overflow(BinOp::Shr, _, r) => {
+                write!(f, "attempt to shift right by {:#?} which would overflow", r)
+            }
+            Overflow(BinOp::Shl, _, r) => {
+                write!(f, "attempt to shift left by {:#?} which would overflow", r)
+            }
             _ => write!(f, "{}", self.description()),
         }
     }

src/librustc_middle/mir/type_foldable.rs

@@ -58,15 +58,14 @@ impl<'tcx> TypeFoldable<'tcx> for Terminator<'tcx> {
             Assert { ref cond, expected, ref msg, target, cleanup } => {
                 use AssertKind::*;
                 let msg = match msg {
-                    BoundsCheck { ref len, ref index } => {
+                    BoundsCheck { len, index } => {
                         BoundsCheck { len: len.fold_with(folder), index: index.fold_with(folder) }
                     }
-                    Overflow(_)
-                    | OverflowNeg
-                    | DivisionByZero
-                    | RemainderByZero
-                    | ResumedAfterReturn(_)
-                    | ResumedAfterPanic(_) => msg.clone(),
+                    Overflow(op, l, r) => Overflow(*op, l.fold_with(folder), r.fold_with(folder)),
+                    OverflowNeg(op) => OverflowNeg(op.fold_with(folder)),
+                    DivisionByZero(op) => DivisionByZero(op.fold_with(folder)),
+                    RemainderByZero(op) => RemainderByZero(op.fold_with(folder)),
+                    ResumedAfterReturn(_) | ResumedAfterPanic(_) => msg.clone(),
                 };
                 Assert { cond: cond.fold_with(folder), expected, msg, target, cleanup }
             }
@@ -117,12 +116,11 @@ impl<'tcx> TypeFoldable<'tcx> for Terminator<'tcx> {
                         BoundsCheck { ref len, ref index } => {
                             len.visit_with(visitor) || index.visit_with(visitor)
                         }
-                        Overflow(_)
-                        | OverflowNeg
-                        | DivisionByZero
-                        | RemainderByZero
-                        | ResumedAfterReturn(_)
-                        | ResumedAfterPanic(_) => false,
+                        Overflow(_, l, r) => l.visit_with(visitor) || r.visit_with(visitor),
+                        OverflowNeg(op) | DivisionByZero(op) | RemainderByZero(op) => {
+                            op.visit_with(visitor)
+                        }
+                        ResumedAfterReturn(_) | ResumedAfterPanic(_) => false,
                     }
                 } else {
                     false

src/librustc_middle/mir/visit.rs

@@ -571,7 +571,13 @@ macro_rules! make_mir_visitor {
                         self.visit_operand(len, location);
                         self.visit_operand(index, location);
                     }
-                    Overflow(_) | OverflowNeg | DivisionByZero | RemainderByZero |
+                    Overflow(_, l, r) => {
+                        self.visit_operand(l, location);
+                        self.visit_operand(r, location);
+                    }
+                    OverflowNeg(op) | DivisionByZero(op) | RemainderByZero(op) => {
+                        self.visit_operand(op, location);
+                    }
                     ResumedAfterReturn(_) | ResumedAfterPanic(_) => {
                         // Nothing to visit
                     }

src/librustc_middle/ty/consts.rs

@@ -0,0 +1,111 @@
+use crate::mir::interpret::truncate;
+use rustc_target::abi::Size;
+
+#[derive(Copy, Clone)]
+/// A type for representing any integer. Only used for printing.
+// FIXME: Use this for the integer-tree representation needed for type level ints and
+// const generics?
+pub struct ConstInt {
+    /// Number of bytes of the integer. Only 1, 2, 4, 8, 16 are legal values.
+    size: u8,
+    /// Whether the value is of a signed integer type.
+    signed: bool,
+    /// Whether the value is a `usize` or `isize` type.
+    is_ptr_sized_integral: bool,
+    /// Raw memory of the integer. All bytes beyond the `size` are unused and must be zero.
+    raw: u128,
+}
+
+impl ConstInt {
+    pub fn new(raw: u128, size: Size, signed: bool, is_ptr_sized_integral: bool) -> Self {
+        assert!(raw <= truncate(u128::MAX, size));
+        Self { raw, size: size.bytes() as u8, signed, is_ptr_sized_integral }
+    }
+}
+
+impl std::fmt::Debug for ConstInt {
+    fn fmt(&self, fmt: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        let Self { size, signed, raw, is_ptr_sized_integral } = *self;
+        if signed {
+            let bit_size = size * 8;
+            let min = 1u128 << (bit_size - 1);
+            let max = min - 1;
+            if raw == min {
+                match (size, is_ptr_sized_integral) {
+                    (_, true) => write!(fmt, "isize::MIN"),
+                    (1, _) => write!(fmt, "i8::MIN"),
+                    (2, _) => write!(fmt, "i16::MIN"),
+                    (4, _) => write!(fmt, "i32::MIN"),
+                    (8, _) => write!(fmt, "i64::MIN"),
+                    (16, _) => write!(fmt, "i128::MIN"),
+                    _ => bug!("ConstInt 0x{:x} with size = {} and signed = {}", raw, size, signed),
+                }
+            } else if raw == max {
+                match (size, is_ptr_sized_integral) {
+                    (_, true) => write!(fmt, "isize::MAX"),
+                    (1, _) => write!(fmt, "i8::MAX"),
+                    (2, _) => write!(fmt, "i16::MAX"),
+                    (4, _) => write!(fmt, "i32::MAX"),
+                    (8, _) => write!(fmt, "i64::MAX"),
+                    (16, _) => write!(fmt, "i128::MAX"),
+                    _ => bug!("ConstInt 0x{:x} with size = {} and signed = {}", raw, size, signed),
+                }
+            } else {
+                match size {
+                    1 => write!(fmt, "{}", raw as i8)?,
+                    2 => write!(fmt, "{}", raw as i16)?,
+                    4 => write!(fmt, "{}", raw as i32)?,
+                    8 => write!(fmt, "{}", raw as i64)?,
+                    16 => write!(fmt, "{}", raw as i128)?,
+                    _ => bug!("ConstInt 0x{:x} with size = {} and signed = {}", raw, size, signed),
+                }
+                if fmt.alternate() {
+                    match (size, is_ptr_sized_integral) {
+                        (_, true) => write!(fmt, "_isize")?,
+                        (1, _) => write!(fmt, "_i8")?,
+                        (2, _) => write!(fmt, "_i16")?,
+                        (4, _) => write!(fmt, "_i32")?,
+                        (8, _) => write!(fmt, "_i64")?,
+                        (16, _) => write!(fmt, "_i128")?,
+                        _ => bug!(),
+                    }
+                }
+                Ok(())
+            }
+        } else {
+            let max = truncate(u128::MAX, Size::from_bytes(size));
+            if raw == max {
+                match (size, is_ptr_sized_integral) {
+                    (_, true) => write!(fmt, "usize::MAX"),
+                    (1, _) => write!(fmt, "u8::MAX"),
+                    (2, _) => write!(fmt, "u16::MAX"),
+                    (4, _) => write!(fmt, "u32::MAX"),
+                    (8, _) => write!(fmt, "u64::MAX"),
+                    (16, _) => write!(fmt, "u128::MAX"),
+                    _ => bug!("ConstInt 0x{:x} with size = {} and signed = {}", raw, size, signed),
+                }
+            } else {
+                match size {
+                    1 => write!(fmt, "{}", raw as u8)?,
+                    2 => write!(fmt, "{}", raw as u16)?,
+                    4 => write!(fmt, "{}", raw as u32)?,
+                    8 => write!(fmt, "{}", raw as u64)?,
+                    16 => write!(fmt, "{}", raw as u128)?,
+                    _ => bug!("ConstInt 0x{:x} with size = {} and signed = {}", raw, size, signed),
+                }
+                if fmt.alternate() {
+                    match (size, is_ptr_sized_integral) {
+                        (_, true) => write!(fmt, "_usize")?,
+                        (1, _) => write!(fmt, "_u8")?,
+                        (2, _) => write!(fmt, "_u16")?,
+                        (4, _) => write!(fmt, "_u32")?,
+                        (8, _) => write!(fmt, "_u64")?,
+                        (16, _) => write!(fmt, "_u128")?,
+                        _ => bug!(),
+                    }
+                }
+                Ok(())
+            }
+        }
+    }
+}

src/librustc_middle/ty/mod.rs

@@ -84,6 +84,8 @@ pub use self::trait_def::TraitDef;
 
 pub use self::query::queries;
 
+pub use self::consts::ConstInt;
+
 pub mod adjustment;
 pub mod binding;
 pub mod cast;
@@ -108,6 +110,7 @@ pub mod trait_def;
 pub mod util;
 pub mod walk;
 
+mod consts;
 mod context;
 mod diagnostics;
 mod instance;

src/librustc_middle/ty/print/pretty.rs

@@ -1,10 +1,8 @@
 use crate::middle::cstore::{ExternCrate, ExternCrateSource};
-use crate::mir::interpret::{
-    sign_extend, truncate, AllocId, ConstValue, GlobalAlloc, Pointer, Scalar,
-};
+use crate::mir::interpret::{AllocId, ConstValue, GlobalAlloc, Pointer, Scalar};
 use crate::ty::layout::IntegerExt;
 use crate::ty::subst::{GenericArg, GenericArgKind, Subst};
-use crate::ty::{self, DefIdTree, ParamConst, Ty, TyCtxt, TypeFoldable};
+use crate::ty::{self, ConstInt, DefIdTree, ParamConst, Ty, TyCtxt, TypeFoldable};
 use rustc_apfloat::ieee::{Double, Single};
 use rustc_apfloat::Float;
 use rustc_ast::ast;
@@ -981,35 +979,14 @@ pub trait PrettyPrinter<'tcx>:
             }
             // Int
             (Scalar::Raw { data, .. }, ty::Uint(ui)) => {
-                let bit_size = Integer::from_attr(&self.tcx(), UnsignedInt(*ui)).size();
-                let max = truncate(u128::MAX, bit_size);
-
-                let ui_str = ui.name_str();
-                if data == max {
-                    p!(write("{}::MAX", ui_str))
-                } else {
-                    if print_ty { p!(write("{}{}", data, ui_str)) } else { p!(write("{}", data)) }
-                };
+                let size = Integer::from_attr(&self.tcx(), UnsignedInt(*ui)).size();
+                let int = ConstInt::new(data, size, false, ty.is_ptr_sized_integral());
+                if print_ty { p!(write("{:#?}", int)) } else { p!(write("{:?}", int)) }
             }
             (Scalar::Raw { data, .. }, ty::Int(i)) => {
                 let size = Integer::from_attr(&self.tcx(), SignedInt(*i)).size();
-                let bit_size = size.bits() as u128;
-                let min = 1u128 << (bit_size - 1);
-                let max = min - 1;
-
-                let i_str = i.name_str();
-                match data {
-                    d if d == min => p!(write("{}::MIN", i_str)),
-                    d if d == max => p!(write("{}::MAX", i_str)),
-                    _ => {
-                        let data = sign_extend(data, size) as i128;
-                        if print_ty {
-                            p!(write("{}{}", data, i_str))
-                        } else {
-                            p!(write("{}", data))
-                        }
-                    }
-                }
+                let int = ConstInt::new(data, size, true, ty.is_ptr_sized_integral());
+                if print_ty { p!(write("{:#?}", int)) } else { p!(write("{:?}", int)) }
             }
             // Char
             (Scalar::Raw { data, .. }, ty::Char) if char::from_u32(data as u32).is_some() => {

src/librustc_mir/const_eval/error.rs

@@ -2,6 +2,7 @@ use std::error::Error;
 use std::fmt;
 
 use rustc_middle::mir::AssertKind;
+use rustc_middle::ty::ConstInt;
 use rustc_span::{Span, Symbol};
 
 use super::InterpCx;
@@ -13,7 +14,7 @@ pub enum ConstEvalErrKind {
     NeedsRfc(String),
     ConstAccessesStatic,
     ModifiedGlobal,
-    AssertFailure(AssertKind<u64>),
+    AssertFailure(AssertKind<ConstInt>),
     Panic { msg: Symbol, line: u32, col: u32, file: Symbol },
 }
 

src/librustc_mir/const_eval/machine.rs

@@ -248,25 +248,19 @@ impl<'mir, 'tcx> interpret::Machine<'mir, 'tcx> for CompileTimeInterpreter<'mir,
         _unwind: Option<mir::BasicBlock>,
     ) -> InterpResult<'tcx> {
         use rustc_middle::mir::AssertKind::*;
-        // Convert `AssertKind<Operand>` to `AssertKind<u64>`.
+        // Convert `AssertKind<Operand>` to `AssertKind<Scalar>`.
+        let eval_to_int =
+            |op| ecx.read_immediate(ecx.eval_operand(op, None)?).map(|x| x.to_const_int());
         let err = match msg {
             BoundsCheck { ref len, ref index } => {
-                let len = ecx
-                    .read_immediate(ecx.eval_operand(len, None)?)
-                    .expect("can't eval len")
-                    .to_scalar()?
-                    .to_machine_usize(&*ecx)?;
-                let index = ecx
-                    .read_immediate(ecx.eval_operand(index, None)?)
-                    .expect("can't eval index")
-                    .to_scalar()?
-                    .to_machine_usize(&*ecx)?;
+                let len = eval_to_int(len)?;
+                let index = eval_to_int(index)?;
                 BoundsCheck { len, index }
             }
-            Overflow(op) => Overflow(*op),
-            OverflowNeg => OverflowNeg,
-            DivisionByZero => DivisionByZero,
-            RemainderByZero => RemainderByZero,
+            Overflow(op, l, r) => Overflow(*op, eval_to_int(l)?, eval_to_int(r)?),
+            OverflowNeg(op) => OverflowNeg(eval_to_int(op)?),
+            DivisionByZero(op) => DivisionByZero(eval_to_int(op)?),
+            RemainderByZero(op) => RemainderByZero(eval_to_int(op)?),
             ResumedAfterReturn(generator_kind) => ResumedAfterReturn(*generator_kind),
             ResumedAfterPanic(generator_kind) => ResumedAfterPanic(*generator_kind),
         };

src/librustc_mir/interpret/operand.rs

@@ -9,7 +9,7 @@ use rustc_hir::def::Namespace;
 use rustc_macros::HashStable;
 use rustc_middle::ty::layout::{PrimitiveExt, TyAndLayout};
 use rustc_middle::ty::print::{FmtPrinter, PrettyPrinter, Printer};
-use rustc_middle::ty::Ty;
+use rustc_middle::ty::{ConstInt, Ty};
 use rustc_middle::{mir, ty};
 use rustc_target::abi::{Abi, HasDataLayout, LayoutOf, Size, TagEncoding};
 use rustc_target::abi::{VariantIdx, Variants};
@@ -207,6 +207,19 @@ impl<'tcx, Tag: Copy> ImmTy<'tcx, Tag> {
     pub fn from_int(i: impl Into<i128>, layout: TyAndLayout<'tcx>) -> Self {
         Self::from_scalar(Scalar::from_int(i, layout.size), layout)
     }
+
+    #[inline]
+    pub fn to_const_int(self) -> ConstInt {
+        assert!(self.layout.ty.is_integral());
+        ConstInt::new(
+            self.to_scalar()
+                .expect("to_const_int doesn't work on scalar pairs")
+                .assert_bits(self.layout.size),
+            self.layout.size,
+            self.layout.ty.is_signed(),
+            self.layout.ty.is_ptr_sized_integral(),
+        )
+    }
 }
 
 impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {

src/librustc_mir/transform/const_prop.rs

@@ -19,7 +19,7 @@ use rustc_middle::mir::{
 };
 use rustc_middle::ty::layout::{HasTyCtxt, LayoutError, TyAndLayout};
 use rustc_middle::ty::subst::{InternalSubsts, Subst};
-use rustc_middle::ty::{self, ConstKind, Instance, ParamEnv, Ty, TyCtxt, TypeFoldable};
+use rustc_middle::ty::{self, ConstInt, ConstKind, Instance, ParamEnv, Ty, TyCtxt, TypeFoldable};
 use rustc_session::lint;
 use rustc_span::{def_id::DefId, Span};
 use rustc_target::abi::{HasDataLayout, LayoutOf, Size, TargetDataLayout};
@@ -449,7 +449,7 @@ impl<'mir, 'tcx> ConstPropagator<'mir, 'tcx> {
         lint: &'static lint::Lint,
         source_info: SourceInfo,
         message: &'static str,
-        panic: AssertKind<u64>,
+        panic: AssertKind<ConstInt>,
     ) -> Option<()> {
         let lint_root = self.lint_root(source_info)?;
         self.tcx.struct_span_lint_hir(lint, lint_root, source_info.span, |lint| {
@@ -466,10 +466,10 @@ impl<'mir, 'tcx> ConstPropagator<'mir, 'tcx> {
         arg: &Operand<'tcx>,
         source_info: SourceInfo,
     ) -> Option<()> {
-        if self.use_ecx(|this| {
+        if let (val, true) = self.use_ecx(|this| {
             let val = this.ecx.read_immediate(this.ecx.eval_operand(arg, None)?)?;
             let (_res, overflow, _ty) = this.ecx.overflowing_unary_op(op, val)?;
-            Ok(overflow)
+            Ok((val, overflow))
         })? {
             // `AssertKind` only has an `OverflowNeg` variant, so make sure that is
             // appropriate to use.
@@ -478,7 +478,7 @@ impl<'mir, 'tcx> ConstPropagator<'mir, 'tcx> {
                 lint::builtin::ARITHMETIC_OVERFLOW,
                 source_info,
                 "this arithmetic operation will overflow",
-                AssertKind::OverflowNeg,
+                AssertKind::OverflowNeg(val.to_const_int()),
             )?;
         }
 
@@ -494,29 +494,44 @@ impl<'mir, 'tcx> ConstPropagator<'mir, 'tcx> {
     ) -> Option<()> {
         let r =
             self.use_ecx(|this| this.ecx.read_immediate(this.ecx.eval_operand(right, None)?))?;
+        let l = self.use_ecx(|this| this.ecx.read_immediate(this.ecx.eval_operand(left, None)?));
         // Check for exceeding shifts *even if* we cannot evaluate the LHS.
         if op == BinOp::Shr || op == BinOp::Shl {
             // We need the type of the LHS. We cannot use `place_layout` as that is the type
             // of the result, which for checked binops is not the same!
             let left_ty = left.ty(&self.local_decls, self.tcx);
-            let left_size_bits = self.ecx.layout_of(left_ty).ok()?.size.bits();
+            let left_size = self.ecx.layout_of(left_ty).ok()?.size;
             let right_size = r.layout.size;
             let r_bits = r.to_scalar().ok();
             // This is basically `force_bits`.
             let r_bits = r_bits.and_then(|r| r.to_bits_or_ptr(right_size, &self.tcx).ok());
-            if r_bits.map_or(false, |b| b >= left_size_bits as u128) {
+            if r_bits.map_or(false, |b| b >= left_size.bits() as u128) {
                 self.report_assert_as_lint(
                     lint::builtin::ARITHMETIC_OVERFLOW,
                     source_info,
                     "this arithmetic operation will overflow",
-                    AssertKind::Overflow(op),
+                    AssertKind::Overflow(
+                        op,
+                        match l {
+                            Some(l) => l.to_const_int(),
+                            // Invent a dummy value, the diagnostic ignores it anyway
+                            None => ConstInt::new(
+                                1,
+                                left_size,
+                                left_ty.is_signed(),
+                                left_ty.is_ptr_sized_integral(),
+                            ),
+                        },
+                        r.to_const_int(),
+                    ),
                 )?;
             }
         }
 
+        let l = l?;
+
         // The remaining operators are handled through `overflowing_binary_op`.
         if self.use_ecx(|this| {
-            let l = this.ecx.read_immediate(this.ecx.eval_operand(left, None)?)?;
             let (_res, overflow, _ty) = this.ecx.overflowing_binary_op(op, l, r)?;
             Ok(overflow)
         })? {
@@ -524,7 +539,7 @@ impl<'mir, 'tcx> ConstPropagator<'mir, 'tcx> {
                 lint::builtin::ARITHMETIC_OVERFLOW,
                 source_info,
                 "this arithmetic operation will overflow",
-                AssertKind::Overflow(op),
+                AssertKind::Overflow(op, l.to_const_int(), r.to_const_int()),
             )?;
         }
 
@@ -949,31 +964,26 @@ impl<'mir, 'tcx> MutVisitor<'tcx> for ConstPropagator<'mir, 'tcx> {
                             }
                             Operand::Constant(_) => {}
                         }
+                        let mut eval_to_int = |op| {
+                            let op = self
+                                .eval_operand(op, source_info)
+                                .expect("if we got here, it must be const");
+                            self.ecx.read_immediate(op).unwrap().to_const_int()
+                        };
                         let msg = match msg {
-                            AssertKind::DivisionByZero => AssertKind::DivisionByZero,
-                            AssertKind::RemainderByZero => AssertKind::RemainderByZero,
+                            AssertKind::DivisionByZero(op) => {
+                                AssertKind::DivisionByZero(eval_to_int(op))
+                            }
+                            AssertKind::RemainderByZero(op) => {
+                                AssertKind::RemainderByZero(eval_to_int(op))
+                            }
                             AssertKind::BoundsCheck { ref len, ref index } => {
-                                let len =
-                                    self.eval_operand(len, source_info).expect("len must be const");
-                                let len = self
-                                    .ecx
-                                    .read_scalar(len)
-                                    .unwrap()
-                                    .to_machine_usize(&self.tcx)
-                                    .unwrap();
-                                let index = self
-                                    .eval_operand(index, source_info)
-                                    .expect("index must be const");
-                                let index = self
-                                    .ecx
-                                    .read_scalar(index)
-                                    .unwrap()
-                                    .to_machine_usize(&self.tcx)
-                                    .unwrap();
+                                let len = eval_to_int(len);
+                                let index = eval_to_int(index);
                                 AssertKind::BoundsCheck { len, index }
                             }
                             // Overflow is are already covered by checks on the binary operators.
-                            AssertKind::Overflow(_) | AssertKind::OverflowNeg => return,
+                            AssertKind::Overflow(..) | AssertKind::OverflowNeg(_) => return,
                             // Need proper const propagator for these.
                             _ => return,
                         };

src/librustc_mir_build/build/expr/as_rvalue.rs

@@ -87,7 +87,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                         block,
                         Operand::Move(is_min),
                         false,
-                        AssertKind::OverflowNeg,
+                        AssertKind::OverflowNeg(arg.to_copy()),
                         expr_span,
                     );
                 }
@@ -288,7 +288,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                 block,
                 source_info,
                 result_value,
-                Rvalue::CheckedBinaryOp(op, lhs, rhs),
+                Rvalue::CheckedBinaryOp(op, lhs.to_copy(), rhs.to_copy()),
             );
             let val_fld = Field::new(0);
             let of_fld = Field::new(1);
@@ -297,7 +297,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
             let val = tcx.mk_place_field(result_value, val_fld, ty);
             let of = tcx.mk_place_field(result_value, of_fld, bool_ty);
 
-            let err = AssertKind::Overflow(op);
+            let err = AssertKind::Overflow(op, lhs, rhs);
 
             block = self.assert(block, Operand::Move(of), false, err, span);
 
@@ -308,11 +308,11 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                 // and 2. there are two possible failure cases, divide-by-zero and overflow.
 
                 let zero_err = if op == BinOp::Div {
-                    AssertKind::DivisionByZero
+                    AssertKind::DivisionByZero(lhs.to_copy())
                 } else {
-                    AssertKind::RemainderByZero
+                    AssertKind::RemainderByZero(lhs.to_copy())
                 };
-                let overflow_err = AssertKind::Overflow(op);
+                let overflow_err = AssertKind::Overflow(op, lhs.to_copy(), rhs.to_copy());
 
                 // Check for / 0
                 let is_zero = self.temp(bool_ty, span);

src/librustdoc/clean/utils.rs

@@ -481,8 +481,8 @@ pub fn print_const(cx: &DocContext<'_>, n: &'tcx ty::Const<'_>) -> String {
         _ => {
             let mut s = n.to_string();
             // array lengths are obviously usize
-            if s.ends_with("usize") {
-                let n = s.len() - "usize".len();
+            if s.ends_with("_usize") {
+                let n = s.len() - "_usize".len();
                 s.truncate(n);
                 if s.ends_with(": ") {
                     let n = s.len() - ": ".len();

src/test/mir-opt/address-of/rustc.address_of_reborrow.SimplifyCfg-initial.after.mir

@@ -128,7 +128,7 @@ fn address_of_reborrow() -> () {
     bb0: {
         StorageLive(_1);                 // scope 0 at $DIR/address-of.rs:4:9: 4:10
         StorageLive(_2);                 // scope 0 at $DIR/address-of.rs:4:14: 4:21
-        _2 = [const 0i32; 10];           // scope 0 at $DIR/address-of.rs:4:14: 4:21
+        _2 = [const 0_i32; 10];          // scope 0 at $DIR/address-of.rs:4:14: 4:21
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000000))
@@ -139,7 +139,7 @@ fn address_of_reborrow() -> () {
         FakeRead(ForLet, _1);            // scope 0 at $DIR/address-of.rs:4:9: 4:10
         StorageLive(_3);                 // scope 1 at $DIR/address-of.rs:5:9: 5:14
         StorageLive(_4);                 // scope 1 at $DIR/address-of.rs:5:22: 5:29
-        _4 = [const 0i32; 10];           // scope 1 at $DIR/address-of.rs:5:22: 5:29
+        _4 = [const 0_i32; 10];          // scope 1 at $DIR/address-of.rs:5:22: 5:29
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000000))

src/test/mir-opt/array-index-is-temporary/32bit/rustc.main.SimplifyCfg-elaborate-drops.after.mir

@@ -25,7 +25,7 @@ fn main() -> () {
 
     bb0: {
         StorageLive(_1);                 // scope 0 at $DIR/array-index-is-temporary.rs:13:9: 13:14
-        _1 = [const 42u32, const 43u32, const 44u32]; // scope 0 at $DIR/array-index-is-temporary.rs:13:17: 13:29
+        _1 = [const 42_u32, const 43_u32, const 44_u32]; // scope 0 at $DIR/array-index-is-temporary.rs:13:17: 13:29
                                          // ty::Const
                                          // + ty: u32
                                          // + val: Value(Scalar(0x0000002a))
@@ -45,7 +45,7 @@ fn main() -> () {
                                          // + span: $DIR/array-index-is-temporary.rs:13:26: 13:28
                                          // + literal: Const { ty: u32, val: Value(Scalar(0x0000002c)) }
         StorageLive(_2);                 // scope 1 at $DIR/array-index-is-temporary.rs:14:9: 14:14
-        _2 = const 1usize;               // scope 1 at $DIR/array-index-is-temporary.rs:14:17: 14:18
+        _2 = const 1_usize;              // scope 1 at $DIR/array-index-is-temporary.rs:14:17: 14:18
                                          // ty::Const
                                          // + ty: usize
                                          // + val: Value(Scalar(0x00000001))

src/test/mir-opt/array-index-is-temporary/64bit/rustc.main.SimplifyCfg-elaborate-drops.after.mir

@@ -25,7 +25,7 @@ fn main() -> () {
 
     bb0: {
         StorageLive(_1);                 // scope 0 at $DIR/array-index-is-temporary.rs:13:9: 13:14
-        _1 = [const 42u32, const 43u32, const 44u32]; // scope 0 at $DIR/array-index-is-temporary.rs:13:17: 13:29
+        _1 = [const 42_u32, const 43_u32, const 44_u32]; // scope 0 at $DIR/array-index-is-temporary.rs:13:17: 13:29
                                          // ty::Const
                                          // + ty: u32
                                          // + val: Value(Scalar(0x0000002a))
@@ -45,7 +45,7 @@ fn main() -> () {
                                          // + span: $DIR/array-index-is-temporary.rs:13:26: 13:28
                                          // + literal: Const { ty: u32, val: Value(Scalar(0x0000002c)) }
         StorageLive(_2);                 // scope 1 at $DIR/array-index-is-temporary.rs:14:9: 14:14
-        _2 = const 1usize;               // scope 1 at $DIR/array-index-is-temporary.rs:14:17: 14:18
+        _2 = const 1_usize;              // scope 1 at $DIR/array-index-is-temporary.rs:14:17: 14:18
                                          // ty::Const
                                          // + ty: usize
                                          // + val: Value(Scalar(0x0000000000000001))

src/test/mir-opt/byte_slice/rustc.main.SimplifyCfg-elaborate-drops.after.mir

@@ -21,7 +21,7 @@ fn main() -> () {
                                          // + span: $DIR/byte_slice.rs:5:13: 5:19
                                          // + literal: Const { ty: &[u8; 3], val: Value(Scalar(alloc0)) }
         StorageLive(_2);                 // scope 1 at $DIR/byte_slice.rs:6:9: 6:10
-        _2 = [const 5u8, const 120u8];   // scope 1 at $DIR/byte_slice.rs:6:13: 6:24
+        _2 = [const 5_u8, const 120_u8]; // scope 1 at $DIR/byte_slice.rs:6:13: 6:24
                                          // ty::Const
                                          // + ty: u8
                                          // + val: Value(Scalar(0x05))

src/test/mir-opt/combine_array_len/32bit/rustc.norm2.InstCombine.diff

@@ -28,7 +28,7 @@
       bb0: {
           StorageLive(_2);                 // scope 0 at $DIR/combine_array_len.rs:5:9: 5:10
           StorageLive(_3);                 // scope 0 at $DIR/combine_array_len.rs:5:15: 5:16
-          _3 = const 0usize;               // scope 0 at $DIR/combine_array_len.rs:5:15: 5:16
+          _3 = const 0_usize;              // scope 0 at $DIR/combine_array_len.rs:5:15: 5:16
                                            // ty::Const
                                            // + ty: usize
                                            // + val: Value(Scalar(0x00000000))
@@ -36,7 +36,7 @@
                                            // + span: $DIR/combine_array_len.rs:5:15: 5:16
                                            // + literal: Const { ty: usize, val: Value(Scalar(0x00000000)) }
 -         _4 = Len(_1);                    // scope 0 at $DIR/combine_array_len.rs:5:13: 5:17
-+         _4 = const 2usize;               // scope 0 at $DIR/combine_array_len.rs:5:13: 5:17
++         _4 = const 2_usize;              // scope 0 at $DIR/combine_array_len.rs:5:13: 5:17
 +                                          // ty::Const
 +                                          // + ty: usize
 +                                          // + val: Value(Scalar(0x00000002))
@@ -52,7 +52,7 @@
           StorageDead(_3);                 // scope 0 at $DIR/combine_array_len.rs:5:17: 5:18
           StorageLive(_6);                 // scope 1 at $DIR/combine_array_len.rs:6:9: 6:10
           StorageLive(_7);                 // scope 1 at $DIR/combine_array_len.rs:6:15: 6:16
-          _7 = const 1usize;               // scope 1 at $DIR/combine_array_len.rs:6:15: 6:16
+          _7 = const 1_usize;              // scope 1 at $DIR/combine_array_len.rs:6:15: 6:16
                                            // ty::Const
                                            // + ty: usize
                                            // + val: Value(Scalar(0x00000001))
@@ -60,7 +60,7 @@
                                            // + span: $DIR/combine_array_len.rs:6:15: 6:16
                                            // + literal: Const { ty: usize, val: Value(Scalar(0x00000001)) }
 -         _8 = Len(_1);                    // scope 1 at $DIR/combine_array_len.rs:6:13: 6:17
-+         _8 = const 2usize;               // scope 1 at $DIR/combine_array_len.rs:6:13: 6:17
++         _8 = const 2_usize;              // scope 1 at $DIR/combine_array_len.rs:6:13: 6:17
 +                                          // ty::Const
 +                                          // + ty: usize
 +                                          // + val: Value(Scalar(0x00000002))

src/test/mir-opt/combine_array_len/64bit/rustc.norm2.InstCombine.diff

@@ -28,7 +28,7 @@
       bb0: {
           StorageLive(_2);                 // scope 0 at $DIR/combine_array_len.rs:5:9: 5:10
           StorageLive(_3);                 // scope 0 at $DIR/combine_array_len.rs:5:15: 5:16
-          _3 = const 0usize;               // scope 0 at $DIR/combine_array_len.rs:5:15: 5:16
+          _3 = const 0_usize;              // scope 0 at $DIR/combine_array_len.rs:5:15: 5:16
                                            // ty::Const
                                            // + ty: usize
                                            // + val: Value(Scalar(0x0000000000000000))
@@ -36,7 +36,7 @@
                                            // + span: $DIR/combine_array_len.rs:5:15: 5:16
                                            // + literal: Const { ty: usize, val: Value(Scalar(0x0000000000000000)) }
 -         _4 = Len(_1);                    // scope 0 at $DIR/combine_array_len.rs:5:13: 5:17
-+         _4 = const 2usize;               // scope 0 at $DIR/combine_array_len.rs:5:13: 5:17
++         _4 = const 2_usize;              // scope 0 at $DIR/combine_array_len.rs:5:13: 5:17
 +                                          // ty::Const
 +                                          // + ty: usize
 +                                          // + val: Value(Scalar(0x0000000000000002))
@@ -52,7 +52,7 @@
           StorageDead(_3);                 // scope 0 at $DIR/combine_array_len.rs:5:17: 5:18
           StorageLive(_6);                 // scope 1 at $DIR/combine_array_len.rs:6:9: 6:10
           StorageLive(_7);                 // scope 1 at $DIR/combine_array_len.rs:6:15: 6:16
-          _7 = const 1usize;               // scope 1 at $DIR/combine_array_len.rs:6:15: 6:16
+          _7 = const 1_usize;              // scope 1 at $DIR/combine_array_len.rs:6:15: 6:16
                                            // ty::Const
                                            // + ty: usize
                                            // + val: Value(Scalar(0x0000000000000001))
@@ -60,7 +60,7 @@
                                            // + span: $DIR/combine_array_len.rs:6:15: 6:16
                                            // + literal: Const { ty: usize, val: Value(Scalar(0x0000000000000001)) }
 -         _8 = Len(_1);                    // scope 1 at $DIR/combine_array_len.rs:6:13: 6:17
-+         _8 = const 2usize;               // scope 1 at $DIR/combine_array_len.rs:6:13: 6:17
++         _8 = const 2_usize;              // scope 1 at $DIR/combine_array_len.rs:6:13: 6:17
 +                                          // ty::Const
 +                                          // + ty: usize
 +                                          // + val: Value(Scalar(0x0000000000000002))

src/test/mir-opt/const_prop/aggregate/rustc.main.ConstProp.diff

@@ -14,7 +14,7 @@
           StorageLive(_1);                 // scope 0 at $DIR/aggregate.rs:5:9: 5:10
           StorageLive(_2);                 // scope 0 at $DIR/aggregate.rs:5:13: 5:24
           StorageLive(_3);                 // scope 0 at $DIR/aggregate.rs:5:13: 5:22
-          _3 = (const 0i32, const 1i32, const 2i32); // scope 0 at $DIR/aggregate.rs:5:13: 5:22
+          _3 = (const 0_i32, const 1_i32, const 2_i32); // scope 0 at $DIR/aggregate.rs:5:13: 5:22
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x00000000))
@@ -34,8 +34,8 @@
                                            // + span: $DIR/aggregate.rs:5:20: 5:21
                                            // + literal: Const { ty: i32, val: Value(Scalar(0x00000002)) }
 -         _2 = (_3.1: i32);                // scope 0 at $DIR/aggregate.rs:5:13: 5:24
--         _1 = Add(move _2, const 0i32);   // scope 0 at $DIR/aggregate.rs:5:13: 5:28
-+         _2 = const 1i32;                 // scope 0 at $DIR/aggregate.rs:5:13: 5:24
+-         _1 = Add(move _2, const 0_i32);  // scope 0 at $DIR/aggregate.rs:5:13: 5:28
++         _2 = const 1_i32;                // scope 0 at $DIR/aggregate.rs:5:13: 5:24
                                            // ty::Const
                                            // + ty: i32
 -                                          // + val: Value(Scalar(0x00000000))
@@ -45,7 +45,7 @@
 -                                          // + literal: Const { ty: i32, val: Value(Scalar(0x00000000)) }
 +                                          // + span: $DIR/aggregate.rs:5:13: 5:24
 +                                          // + literal: Const { ty: i32, val: Value(Scalar(0x00000001)) }
-+         _1 = const 1i32;                 // scope 0 at $DIR/aggregate.rs:5:13: 5:28
++         _1 = const 1_i32;                // scope 0 at $DIR/aggregate.rs:5:13: 5:28
 +                                          // ty::Const
 +                                          // + ty: i32
 +                                          // + val: Value(Scalar(0x00000001))

src/test/mir-opt/const_prop/array_index/32bit/rustc.main.ConstProp.diff

@@ -15,7 +15,7 @@
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/array_index.rs:5:9: 5:10
           StorageLive(_2);                 // scope 0 at $DIR/array_index.rs:5:18: 5:30
-          _2 = [const 0u32, const 1u32, const 2u32, const 3u32]; // scope 0 at $DIR/array_index.rs:5:18: 5:30
+          _2 = [const 0_u32, const 1_u32, const 2_u32, const 3_u32]; // scope 0 at $DIR/array_index.rs:5:18: 5:30
                                            // ty::Const
                                            // + ty: u32
                                            // + val: Value(Scalar(0x00000000))
@@ -41,14 +41,14 @@
                                            // + span: $DIR/array_index.rs:5:28: 5:29
                                            // + literal: Const { ty: u32, val: Value(Scalar(0x00000003)) }
           StorageLive(_3);                 // scope 0 at $DIR/array_index.rs:5:31: 5:32
-          _3 = const 2usize;               // scope 0 at $DIR/array_index.rs:5:31: 5:32
+          _3 = const 2_usize;              // scope 0 at $DIR/array_index.rs:5:31: 5:32
                                            // ty::Const
                                            // + ty: usize
                                            // + val: Value(Scalar(0x00000002))
                                            // mir::Constant
                                            // + span: $DIR/array_index.rs:5:31: 5:32
                                            // + literal: Const { ty: usize, val: Value(Scalar(0x00000002)) }
-          _4 = const 4usize;               // scope 0 at $DIR/array_index.rs:5:18: 5:33
+          _4 = const 4_usize;              // scope 0 at $DIR/array_index.rs:5:18: 5:33
                                            // ty::Const
                                            // + ty: usize
                                            // + val: Value(Scalar(0x00000004))
@@ -75,7 +75,7 @@
   
       bb1: {
 -         _1 = _2[_3];                     // scope 0 at $DIR/array_index.rs:5:18: 5:33
-+         _1 = const 2u32;                 // scope 0 at $DIR/array_index.rs:5:18: 5:33
++         _1 = const 2_u32;                // scope 0 at $DIR/array_index.rs:5:18: 5:33
 +                                          // ty::Const
 +                                          // + ty: u32
 +                                          // + val: Value(Scalar(0x00000002))

src/test/mir-opt/const_prop/array_index/64bit/rustc.main.ConstProp.diff

@@ -15,7 +15,7 @@
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/array_index.rs:5:9: 5:10
           StorageLive(_2);                 // scope 0 at $DIR/array_index.rs:5:18: 5:30
-          _2 = [const 0u32, const 1u32, const 2u32, const 3u32]; // scope 0 at $DIR/array_index.rs:5:18: 5:30
+          _2 = [const 0_u32, const 1_u32, const 2_u32, const 3_u32]; // scope 0 at $DIR/array_index.rs:5:18: 5:30
                                            // ty::Const
                                            // + ty: u32
                                            // + val: Value(Scalar(0x00000000))
@@ -41,14 +41,14 @@
                                            // + span: $DIR/array_index.rs:5:28: 5:29
                                            // + literal: Const { ty: u32, val: Value(Scalar(0x00000003)) }
           StorageLive(_3);                 // scope 0 at $DIR/array_index.rs:5:31: 5:32
-          _3 = const 2usize;               // scope 0 at $DIR/array_index.rs:5:31: 5:32
+          _3 = const 2_usize;              // scope 0 at $DIR/array_index.rs:5:31: 5:32
                                            // ty::Const
                                            // + ty: usize
                                            // + val: Value(Scalar(0x0000000000000002))
                                            // mir::Constant
                                            // + span: $DIR/array_index.rs:5:31: 5:32
                                            // + literal: Const { ty: usize, val: Value(Scalar(0x0000000000000002)) }
-          _4 = const 4usize;               // scope 0 at $DIR/array_index.rs:5:18: 5:33
+          _4 = const 4_usize;              // scope 0 at $DIR/array_index.rs:5:18: 5:33
                                            // ty::Const
                                            // + ty: usize
                                            // + val: Value(Scalar(0x0000000000000004))
@@ -75,7 +75,7 @@
   
       bb1: {
 -         _1 = _2[_3];                     // scope 0 at $DIR/array_index.rs:5:18: 5:33
-+         _1 = const 2u32;                 // scope 0 at $DIR/array_index.rs:5:18: 5:33
++         _1 = const 2_u32;                // scope 0 at $DIR/array_index.rs:5:18: 5:33
 +                                          // ty::Const
 +                                          // + ty: u32
 +                                          // + val: Value(Scalar(0x00000002))

src/test/mir-opt/const_prop/bad_op_div_by_zero/rustc.main.ConstProp.diff

@@ -19,7 +19,7 @@
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/bad_op_div_by_zero.rs:4:9: 4:10
-          _1 = const 0i32;                 // scope 0 at $DIR/bad_op_div_by_zero.rs:4:13: 4:14
+          _1 = const 0_i32;                // scope 0 at $DIR/bad_op_div_by_zero.rs:4:13: 4:14
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x00000000))
@@ -29,8 +29,8 @@
           StorageLive(_2);                 // scope 1 at $DIR/bad_op_div_by_zero.rs:5:9: 5:11
           StorageLive(_3);                 // scope 1 at $DIR/bad_op_div_by_zero.rs:5:18: 5:19
 -         _3 = _1;                         // scope 1 at $DIR/bad_op_div_by_zero.rs:5:18: 5:19
--         _4 = Eq(_3, const 0i32);         // scope 1 at $DIR/bad_op_div_by_zero.rs:5:14: 5:19
-+         _3 = const 0i32;                 // scope 1 at $DIR/bad_op_div_by_zero.rs:5:18: 5:19
+-         _4 = Eq(_3, const 0_i32);        // scope 1 at $DIR/bad_op_div_by_zero.rs:5:14: 5:19
++         _3 = const 0_i32;                // scope 1 at $DIR/bad_op_div_by_zero.rs:5:18: 5:19
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x00000000))
@@ -45,11 +45,17 @@
 +                                          // mir::Constant
 +                                          // + span: $DIR/bad_op_div_by_zero.rs:5:14: 5:19
 +                                          // + literal: Const { ty: bool, val: Value(Scalar(0x01)) }
-          assert(!move _4, "attempt to divide by zero") -> bb1; // scope 1 at $DIR/bad_op_div_by_zero.rs:5:14: 5:19
+          assert(!move _4, "attempt to divide {} by zero", const 1_i32) -> bb1; // scope 1 at $DIR/bad_op_div_by_zero.rs:5:14: 5:19
+                                           // ty::Const
+                                           // + ty: i32
+                                           // + val: Value(Scalar(0x00000001))
+                                           // mir::Constant
+                                           // + span: $DIR/bad_op_div_by_zero.rs:5:14: 5:15
+                                           // + literal: Const { ty: i32, val: Value(Scalar(0x00000001)) }
       }
   
       bb1: {
--         _5 = Eq(_3, const -1i32);        // scope 1 at $DIR/bad_op_div_by_zero.rs:5:14: 5:19
+-         _5 = Eq(_3, const -1_i32);       // scope 1 at $DIR/bad_op_div_by_zero.rs:5:14: 5:19
 +         _5 = const false;                // scope 1 at $DIR/bad_op_div_by_zero.rs:5:14: 5:19
                                            // ty::Const
 -                                          // + ty: i32
@@ -59,7 +65,7 @@
                                            // mir::Constant
                                            // + span: $DIR/bad_op_div_by_zero.rs:5:14: 5:19
 -                                          // + literal: Const { ty: i32, val: Value(Scalar(0xffffffff)) }
--         _6 = Eq(const 1i32, const i32::MIN); // scope 1 at $DIR/bad_op_div_by_zero.rs:5:14: 5:19
+-         _6 = Eq(const 1_i32, const i32::MIN); // scope 1 at $DIR/bad_op_div_by_zero.rs:5:14: 5:19
 +                                          // + literal: Const { ty: bool, val: Value(Scalar(0x00)) }
 +         _6 = const false;                // scope 1 at $DIR/bad_op_div_by_zero.rs:5:14: 5:19
                                            // ty::Const
@@ -82,19 +88,25 @@
                                            // + span: $DIR/bad_op_div_by_zero.rs:5:14: 5:19
 -                                          // + literal: Const { ty: i32, val: Value(Scalar(0x80000000)) }
 -         _7 = BitAnd(move _5, move _6);   // scope 1 at $DIR/bad_op_div_by_zero.rs:5:14: 5:19
--         assert(!move _7, "attempt to divide with overflow") -> bb2; // scope 1 at $DIR/bad_op_div_by_zero.rs:5:14: 5:19
+-         assert(!move _7, "attempt to compute `{} / {}` which would overflow", const 1_i32, _3) -> bb2; // scope 1 at $DIR/bad_op_div_by_zero.rs:5:14: 5:19
 +                                          // + literal: Const { ty: bool, val: Value(Scalar(0x00)) }
-+         assert(!const false, "attempt to divide with overflow") -> bb2; // scope 1 at $DIR/bad_op_div_by_zero.rs:5:14: 5:19
++         assert(!const false, "attempt to compute `{} / {}` which would overflow", const 1_i32, _3) -> bb2; // scope 1 at $DIR/bad_op_div_by_zero.rs:5:14: 5:19
 +                                          // ty::Const
 +                                          // + ty: bool
 +                                          // + val: Value(Scalar(0x00))
 +                                          // mir::Constant
 +                                          // + span: $DIR/bad_op_div_by_zero.rs:5:14: 5:19
 +                                          // + literal: Const { ty: bool, val: Value(Scalar(0x00)) }
+                                           // ty::Const
+                                           // + ty: i32
+                                           // + val: Value(Scalar(0x00000001))
+                                           // mir::Constant
+                                           // + span: $DIR/bad_op_div_by_zero.rs:5:14: 5:15
+                                           // + literal: Const { ty: i32, val: Value(Scalar(0x00000001)) }
       }
   
       bb2: {
-          _2 = Div(const 1i32, move _3);   // scope 1 at $DIR/bad_op_div_by_zero.rs:5:14: 5:19
+          _2 = Div(const 1_i32, move _3);  // scope 1 at $DIR/bad_op_div_by_zero.rs:5:14: 5:19
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x00000001))

src/test/mir-opt/const_prop/bad_op_mod_by_zero/rustc.main.ConstProp.diff

@@ -19,7 +19,7 @@
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/bad_op_mod_by_zero.rs:4:9: 4:10
-          _1 = const 0i32;                 // scope 0 at $DIR/bad_op_mod_by_zero.rs:4:13: 4:14
+          _1 = const 0_i32;                // scope 0 at $DIR/bad_op_mod_by_zero.rs:4:13: 4:14
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x00000000))
@@ -29,8 +29,8 @@
           StorageLive(_2);                 // scope 1 at $DIR/bad_op_mod_by_zero.rs:5:9: 5:11
           StorageLive(_3);                 // scope 1 at $DIR/bad_op_mod_by_zero.rs:5:18: 5:19
 -         _3 = _1;                         // scope 1 at $DIR/bad_op_mod_by_zero.rs:5:18: 5:19
--         _4 = Eq(_3, const 0i32);         // scope 1 at $DIR/bad_op_mod_by_zero.rs:5:14: 5:19
-+         _3 = const 0i32;                 // scope 1 at $DIR/bad_op_mod_by_zero.rs:5:18: 5:19
+-         _4 = Eq(_3, const 0_i32);        // scope 1 at $DIR/bad_op_mod_by_zero.rs:5:14: 5:19
++         _3 = const 0_i32;                // scope 1 at $DIR/bad_op_mod_by_zero.rs:5:18: 5:19
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x00000000))
@@ -45,11 +45,17 @@
 +                                          // mir::Constant
 +                                          // + span: $DIR/bad_op_mod_by_zero.rs:5:14: 5:19
 +                                          // + literal: Const { ty: bool, val: Value(Scalar(0x01)) }
-          assert(!move _4, "attempt to calculate the remainder with a divisor of zero") -> bb1; // scope 1 at $DIR/bad_op_mod_by_zero.rs:5:14: 5:19
+          assert(!move _4, "attempt to calculate the remainder of {} with a divisor of zero", const 1_i32) -> bb1; // scope 1 at $DIR/bad_op_mod_by_zero.rs:5:14: 5:19
+                                           // ty::Const
+                                           // + ty: i32
+                                           // + val: Value(Scalar(0x00000001))
+                                           // mir::Constant
+                                           // + span: $DIR/bad_op_mod_by_zero.rs:5:14: 5:15
+                                           // + literal: Const { ty: i32, val: Value(Scalar(0x00000001)) }
       }
   
       bb1: {
--         _5 = Eq(_3, const -1i32);        // scope 1 at $DIR/bad_op_mod_by_zero.rs:5:14: 5:19
+-         _5 = Eq(_3, const -1_i32);       // scope 1 at $DIR/bad_op_mod_by_zero.rs:5:14: 5:19
 +         _5 = const false;                // scope 1 at $DIR/bad_op_mod_by_zero.rs:5:14: 5:19
                                            // ty::Const
 -                                          // + ty: i32
@@ -59,7 +65,7 @@
                                            // mir::Constant
                                            // + span: $DIR/bad_op_mod_by_zero.rs:5:14: 5:19
 -                                          // + literal: Const { ty: i32, val: Value(Scalar(0xffffffff)) }
--         _6 = Eq(const 1i32, const i32::MIN); // scope 1 at $DIR/bad_op_mod_by_zero.rs:5:14: 5:19
+-         _6 = Eq(const 1_i32, const i32::MIN); // scope 1 at $DIR/bad_op_mod_by_zero.rs:5:14: 5:19
 +                                          // + literal: Const { ty: bool, val: Value(Scalar(0x00)) }
 +         _6 = const false;                // scope 1 at $DIR/bad_op_mod_by_zero.rs:5:14: 5:19
                                            // ty::Const
@@ -82,19 +88,25 @@
                                            // + span: $DIR/bad_op_mod_by_zero.rs:5:14: 5:19
 -                                          // + literal: Const { ty: i32, val: Value(Scalar(0x80000000)) }
 -         _7 = BitAnd(move _5, move _6);   // scope 1 at $DIR/bad_op_mod_by_zero.rs:5:14: 5:19
--         assert(!move _7, "attempt to calculate the remainder with overflow") -> bb2; // scope 1 at $DIR/bad_op_mod_by_zero.rs:5:14: 5:19
+-         assert(!move _7, "attempt to compute the remainder of `{} % {}` which would overflow", const 1_i32, _3) -> bb2; // scope 1 at $DIR/bad_op_mod_by_zero.rs:5:14: 5:19
 +                                          // + literal: Const { ty: bool, val: Value(Scalar(0x00)) }
-+         assert(!const false, "attempt to calculate the remainder with overflow") -> bb2; // scope 1 at $DIR/bad_op_mod_by_zero.rs:5:14: 5:19
++         assert(!const false, "attempt to compute the remainder of `{} % {}` which would overflow", const 1_i32, _3) -> bb2; // scope 1 at $DIR/bad_op_mod_by_zero.rs:5:14: 5:19
 +                                          // ty::Const
 +                                          // + ty: bool
 +                                          // + val: Value(Scalar(0x00))
 +                                          // mir::Constant
 +                                          // + span: $DIR/bad_op_mod_by_zero.rs:5:14: 5:19
 +                                          // + literal: Const { ty: bool, val: Value(Scalar(0x00)) }
+                                           // ty::Const
+                                           // + ty: i32
+                                           // + val: Value(Scalar(0x00000001))
+                                           // mir::Constant
+                                           // + span: $DIR/bad_op_mod_by_zero.rs:5:14: 5:15
+                                           // + literal: Const { ty: i32, val: Value(Scalar(0x00000001)) }
       }
   
       bb2: {
-          _2 = Rem(const 1i32, move _3);   // scope 1 at $DIR/bad_op_mod_by_zero.rs:5:14: 5:19
+          _2 = Rem(const 1_i32, move _3);  // scope 1 at $DIR/bad_op_mod_by_zero.rs:5:14: 5:19
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x00000001))

src/test/mir-opt/const_prop/bad_op_unsafe_oob_for_slices/32bit/rustc.main.ConstProp.diff

@@ -39,7 +39,7 @@
           StorageDead(_3);                 // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:5:35: 5:36
           StorageLive(_5);                 // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:7:13: 7:15
           StorageLive(_6);                 // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:7:23: 7:24
-          _6 = const 3usize;               // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:7:23: 7:24
+          _6 = const 3_usize;              // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:7:23: 7:24
                                            // ty::Const
                                            // + ty: usize
                                            // + val: Value(Scalar(0x00000003))

src/test/mir-opt/const_prop/bad_op_unsafe_oob_for_slices/64bit/rustc.main.ConstProp.diff

@@ -39,7 +39,7 @@
           StorageDead(_3);                 // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:5:35: 5:36
           StorageLive(_5);                 // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:7:13: 7:15
           StorageLive(_6);                 // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:7:23: 7:24
-          _6 = const 3usize;               // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:7:23: 7:24
+          _6 = const 3_usize;              // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:7:23: 7:24
                                            // ty::Const
                                            // + ty: usize
                                            // + val: Value(Scalar(0x0000000000000003))

src/test/mir-opt/const_prop/boxes/rustc.main.ConstProp.diff

@@ -17,7 +17,7 @@
           StorageLive(_3);                 // scope 0 at $DIR/boxes.rs:12:14: 12:22
           StorageLive(_4);                 // scope 0 at $DIR/boxes.rs:12:14: 12:22
           _4 = Box(i32);                   // scope 0 at $DIR/boxes.rs:12:14: 12:22
-          (*_4) = const 42i32;             // scope 0 at $DIR/boxes.rs:12:19: 12:21
+          (*_4) = const 42_i32;            // scope 0 at $DIR/boxes.rs:12:19: 12:21
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x0000002a))
@@ -27,7 +27,7 @@
           _3 = move _4;                    // scope 0 at $DIR/boxes.rs:12:14: 12:22
           StorageDead(_4);                 // scope 0 at $DIR/boxes.rs:12:21: 12:22
           _2 = (*_3);                      // scope 0 at $DIR/boxes.rs:12:13: 12:22
-          _1 = Add(move _2, const 0i32);   // scope 0 at $DIR/boxes.rs:12:13: 12:26
+          _1 = Add(move _2, const 0_i32);  // scope 0 at $DIR/boxes.rs:12:13: 12:26
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x00000000))

src/test/mir-opt/const_prop/cast/rustc.main.ConstProp.diff

@@ -14,8 +14,8 @@
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/cast.rs:4:9: 4:10
--         _1 = const 42u8 as u32 (Misc);   // scope 0 at $DIR/cast.rs:4:13: 4:24
-+         _1 = const 42u32;                // scope 0 at $DIR/cast.rs:4:13: 4:24
+-         _1 = const 42_u8 as u32 (Misc);  // scope 0 at $DIR/cast.rs:4:13: 4:24
++         _1 = const 42_u32;               // scope 0 at $DIR/cast.rs:4:13: 4:24
                                            // ty::Const
 -                                          // + ty: u8
 -                                          // + val: Value(Scalar(0x2a))
@@ -23,7 +23,7 @@
 -                                          // + span: $DIR/cast.rs:4:13: 4:17
 -                                          // + literal: Const { ty: u8, val: Value(Scalar(0x2a)) }
 -         StorageLive(_2);                 // scope 1 at $DIR/cast.rs:6:9: 6:10
--         _2 = const 42u32 as u8 (Misc);   // scope 1 at $DIR/cast.rs:6:13: 6:24
+-         _2 = const 42_u32 as u8 (Misc);  // scope 1 at $DIR/cast.rs:6:13: 6:24
 -                                          // ty::Const
                                            // + ty: u32
                                            // + val: Value(Scalar(0x0000002a))
@@ -32,7 +32,7 @@
 +                                          // + span: $DIR/cast.rs:4:13: 4:24
                                            // + literal: Const { ty: u32, val: Value(Scalar(0x0000002a)) }
 +         StorageLive(_2);                 // scope 1 at $DIR/cast.rs:6:9: 6:10
-+         _2 = const 42u8;                 // scope 1 at $DIR/cast.rs:6:13: 6:24
++         _2 = const 42_u8;                // scope 1 at $DIR/cast.rs:6:13: 6:24
 +                                          // ty::Const
 +                                          // + ty: u8
 +                                          // + val: Value(Scalar(0x2a))

src/test/mir-opt/const_prop/checked_add/rustc.main.ConstProp.diff

@@ -11,8 +11,8 @@
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/checked_add.rs:5:9: 5:10
--         _2 = CheckedAdd(const 1u32, const 1u32); // scope 0 at $DIR/checked_add.rs:5:18: 5:23
-+         _2 = (const 2u32, const false);  // scope 0 at $DIR/checked_add.rs:5:18: 5:23
+-         _2 = CheckedAdd(const 1_u32, const 1_u32); // scope 0 at $DIR/checked_add.rs:5:18: 5:23
++         _2 = (const 2_u32, const false); // scope 0 at $DIR/checked_add.rs:5:18: 5:23
                                            // ty::Const
                                            // + ty: u32
 -                                          // + val: Value(Scalar(0x00000001))
@@ -30,21 +30,33 @@
                                            // mir::Constant
 -                                          // + span: $DIR/checked_add.rs:5:22: 5:23
 -                                          // + literal: Const { ty: u32, val: Value(Scalar(0x00000001)) }
--         assert(!move (_2.1: bool), "attempt to add with overflow") -> bb1; // scope 0 at $DIR/checked_add.rs:5:18: 5:23
+-         assert(!move (_2.1: bool), "attempt to compute `{} + {}` which would overflow", const 1_u32, const 1_u32) -> bb1; // scope 0 at $DIR/checked_add.rs:5:18: 5:23
 +                                          // + span: $DIR/checked_add.rs:5:18: 5:23
 +                                          // + literal: Const { ty: bool, val: Value(Scalar(0x00)) }
-+         assert(!const false, "attempt to add with overflow") -> bb1; // scope 0 at $DIR/checked_add.rs:5:18: 5:23
-+                                          // ty::Const
++         assert(!const false, "attempt to compute `{} + {}` which would overflow", const 1_u32, const 1_u32) -> bb1; // scope 0 at $DIR/checked_add.rs:5:18: 5:23
+                                           // ty::Const
 +                                          // + ty: bool
 +                                          // + val: Value(Scalar(0x00))
 +                                          // mir::Constant
 +                                          // + span: $DIR/checked_add.rs:5:18: 5:23
 +                                          // + literal: Const { ty: bool, val: Value(Scalar(0x00)) }
++                                          // ty::Const
+                                           // + ty: u32
+                                           // + val: Value(Scalar(0x00000001))
+                                           // mir::Constant
+                                           // + span: $DIR/checked_add.rs:5:18: 5:19
+                                           // + literal: Const { ty: u32, val: Value(Scalar(0x00000001)) }
+                                           // ty::Const
+                                           // + ty: u32
+                                           // + val: Value(Scalar(0x00000001))
+                                           // mir::Constant
+                                           // + span: $DIR/checked_add.rs:5:22: 5:23
+                                           // + literal: Const { ty: u32, val: Value(Scalar(0x00000001)) }
       }
   
       bb1: {
 -         _1 = move (_2.0: u32);           // scope 0 at $DIR/checked_add.rs:5:18: 5:23
-+         _1 = const 2u32;                 // scope 0 at $DIR/checked_add.rs:5:18: 5:23
++         _1 = const 2_u32;                // scope 0 at $DIR/checked_add.rs:5:18: 5:23
 +                                          // ty::Const
 +                                          // + ty: u32
 +                                          // + val: Value(Scalar(0x00000002))

src/test/mir-opt/const_prop/discriminant/32bit/rustc.main.ConstProp.diff

@@ -25,17 +25,17 @@
 -                                          // + span: $DIR/discriminant.rs:11:39: 11:43
 -                                          // + literal: Const { ty: bool, val: Value(Scalar(0x01)) }
 -         _4 = discriminant(_3);           // scope 0 at $DIR/discriminant.rs:11:21: 11:31
--         switchInt(move _4) -> [1isize: bb2, otherwise: bb1]; // scope 0 at $DIR/discriminant.rs:11:21: 11:31
+-         switchInt(move _4) -> [1_isize: bb2, otherwise: bb1]; // scope 0 at $DIR/discriminant.rs:11:21: 11:31
 +                                          // + span: $DIR/discriminant.rs:11:34: 11:44
 +                                          // + literal: Const { ty: std::option::Option<bool>, val: Value(Scalar(0x01)) }
-+         _4 = const 1isize;               // scope 0 at $DIR/discriminant.rs:11:21: 11:31
++         _4 = const 1_isize;              // scope 0 at $DIR/discriminant.rs:11:21: 11:31
 +                                          // ty::Const
 +                                          // + ty: isize
 +                                          // + val: Value(Scalar(0x00000001))
 +                                          // mir::Constant
 +                                          // + span: $DIR/discriminant.rs:11:21: 11:31
 +                                          // + literal: Const { ty: isize, val: Value(Scalar(0x00000001)) }
-+         switchInt(const 1isize) -> [1isize: bb2, otherwise: bb1]; // scope 0 at $DIR/discriminant.rs:11:21: 11:31
++         switchInt(const 1_isize) -> [1_isize: bb2, otherwise: bb1]; // scope 0 at $DIR/discriminant.rs:11:21: 11:31
 +                                          // ty::Const
 +                                          // + ty: isize
 +                                          // + val: Value(Scalar(0x00000001))
@@ -45,7 +45,7 @@
       }
   
       bb1: {
-          _2 = const 10i32;                // scope 0 at $DIR/discriminant.rs:11:59: 11:61
+          _2 = const 10_i32;               // scope 0 at $DIR/discriminant.rs:11:59: 11:61
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x0000000a))
@@ -60,7 +60,7 @@
       }
   
       bb3: {
-          _2 = const 42i32;                // scope 0 at $DIR/discriminant.rs:11:47: 11:49
+          _2 = const 42_i32;               // scope 0 at $DIR/discriminant.rs:11:47: 11:49
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x0000002a))
@@ -71,7 +71,7 @@
       }
   
       bb4: {
-          _1 = Add(move _2, const 0i32);   // scope 0 at $DIR/discriminant.rs:11:13: 11:68
+          _1 = Add(move _2, const 0_i32);  // scope 0 at $DIR/discriminant.rs:11:13: 11:68
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x00000000))

src/test/mir-opt/const_prop/discriminant/64bit/rustc.main.ConstProp.diff

@@ -25,17 +25,17 @@
 -                                          // + span: $DIR/discriminant.rs:11:39: 11:43
 -                                          // + literal: Const { ty: bool, val: Value(Scalar(0x01)) }
 -         _4 = discriminant(_3);           // scope 0 at $DIR/discriminant.rs:11:21: 11:31
--         switchInt(move _4) -> [1isize: bb2, otherwise: bb1]; // scope 0 at $DIR/discriminant.rs:11:21: 11:31
+-         switchInt(move _4) -> [1_isize: bb2, otherwise: bb1]; // scope 0 at $DIR/discriminant.rs:11:21: 11:31
 +                                          // + span: $DIR/discriminant.rs:11:34: 11:44
 +                                          // + literal: Const { ty: std::option::Option<bool>, val: Value(Scalar(0x01)) }
-+         _4 = const 1isize;               // scope 0 at $DIR/discriminant.rs:11:21: 11:31
++         _4 = const 1_isize;              // scope 0 at $DIR/discriminant.rs:11:21: 11:31
 +                                          // ty::Const
 +                                          // + ty: isize
 +                                          // + val: Value(Scalar(0x0000000000000001))
 +                                          // mir::Constant
 +                                          // + span: $DIR/discriminant.rs:11:21: 11:31
 +                                          // + literal: Const { ty: isize, val: Value(Scalar(0x0000000000000001)) }
-+         switchInt(const 1isize) -> [1isize: bb2, otherwise: bb1]; // scope 0 at $DIR/discriminant.rs:11:21: 11:31
++         switchInt(const 1_isize) -> [1_isize: bb2, otherwise: bb1]; // scope 0 at $DIR/discriminant.rs:11:21: 11:31
 +                                          // ty::Const
 +                                          // + ty: isize
 +                                          // + val: Value(Scalar(0x0000000000000001))
@@ -45,7 +45,7 @@
       }
   
       bb1: {
-          _2 = const 10i32;                // scope 0 at $DIR/discriminant.rs:11:59: 11:61
+          _2 = const 10_i32;               // scope 0 at $DIR/discriminant.rs:11:59: 11:61
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x0000000a))
@@ -60,7 +60,7 @@
       }
   
       bb3: {
-          _2 = const 42i32;                // scope 0 at $DIR/discriminant.rs:11:47: 11:49
+          _2 = const 42_i32;               // scope 0 at $DIR/discriminant.rs:11:47: 11:49
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x0000002a))
@@ -71,7 +71,7 @@
       }
   
       bb4: {
-          _1 = Add(move _2, const 0i32);   // scope 0 at $DIR/discriminant.rs:11:13: 11:68
+          _1 = Add(move _2, const 0_i32);  // scope 0 at $DIR/discriminant.rs:11:13: 11:68
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x00000000))

src/test/mir-opt/const_prop/indirect/rustc.main.ConstProp.diff

@@ -13,8 +13,8 @@
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/indirect.rs:5:9: 5:10
           StorageLive(_2);                 // scope 0 at $DIR/indirect.rs:5:13: 5:25
--         _2 = const 2u32 as u8 (Misc);    // scope 0 at $DIR/indirect.rs:5:13: 5:25
-+         _2 = const 2u8;                  // scope 0 at $DIR/indirect.rs:5:13: 5:25
+-         _2 = const 2_u32 as u8 (Misc);   // scope 0 at $DIR/indirect.rs:5:13: 5:25
++         _2 = const 2_u8;                 // scope 0 at $DIR/indirect.rs:5:13: 5:25
                                            // ty::Const
 -                                          // + ty: u32
 -                                          // + val: Value(Scalar(0x00000002))
@@ -23,10 +23,10 @@
                                            // mir::Constant
 -                                          // + span: $DIR/indirect.rs:5:14: 5:18
 -                                          // + literal: Const { ty: u32, val: Value(Scalar(0x00000002)) }
--         _3 = CheckedAdd(move _2, const 1u8); // scope 0 at $DIR/indirect.rs:5:13: 5:29
+-         _3 = CheckedAdd(_2, const 1_u8); // scope 0 at $DIR/indirect.rs:5:13: 5:29
 +                                          // + span: $DIR/indirect.rs:5:13: 5:25
 +                                          // + literal: Const { ty: u8, val: Value(Scalar(0x02)) }
-+         _3 = (const 3u8, const false);   // scope 0 at $DIR/indirect.rs:5:13: 5:29
++         _3 = (const 3_u8, const false);  // scope 0 at $DIR/indirect.rs:5:13: 5:29
                                            // ty::Const
                                            // + ty: u8
 -                                          // + val: Value(Scalar(0x01))
@@ -34,27 +34,33 @@
                                            // mir::Constant
 -                                          // + span: $DIR/indirect.rs:5:28: 5:29
 -                                          // + literal: Const { ty: u8, val: Value(Scalar(0x01)) }
--         assert(!move (_3.1: bool), "attempt to add with overflow") -> bb1; // scope 0 at $DIR/indirect.rs:5:13: 5:29
+-         assert(!move (_3.1: bool), "attempt to compute `{} + {}` which would overflow", move _2, const 1_u8) -> bb1; // scope 0 at $DIR/indirect.rs:5:13: 5:29
 +                                          // + span: $DIR/indirect.rs:5:13: 5:29
 +                                          // + literal: Const { ty: u8, val: Value(Scalar(0x03)) }
+                                           // ty::Const
++                                          // + ty: bool
++                                          // + val: Value(Scalar(0x00))
++                                          // mir::Constant
++                                          // + span: $DIR/indirect.rs:5:13: 5:29
++                                          // + literal: Const { ty: bool, val: Value(Scalar(0x00)) }
++         assert(!const false, "attempt to compute `{} + {}` which would overflow", move _2, const 1_u8) -> bb1; // scope 0 at $DIR/indirect.rs:5:13: 5:29
 +                                          // ty::Const
 +                                          // + ty: bool
 +                                          // + val: Value(Scalar(0x00))
 +                                          // mir::Constant
 +                                          // + span: $DIR/indirect.rs:5:13: 5:29
 +                                          // + literal: Const { ty: bool, val: Value(Scalar(0x00)) }
-+         assert(!const false, "attempt to add with overflow") -> bb1; // scope 0 at $DIR/indirect.rs:5:13: 5:29
 +                                          // ty::Const
-+                                          // + ty: bool
-+                                          // + val: Value(Scalar(0x00))
-+                                          // mir::Constant
-+                                          // + span: $DIR/indirect.rs:5:13: 5:29
-+                                          // + literal: Const { ty: bool, val: Value(Scalar(0x00)) }
+                                           // + ty: u8
+                                           // + val: Value(Scalar(0x01))
+                                           // mir::Constant
+                                           // + span: $DIR/indirect.rs:5:28: 5:29
+                                           // + literal: Const { ty: u8, val: Value(Scalar(0x01)) }
       }
   
       bb1: {
 -         _1 = move (_3.0: u8);            // scope 0 at $DIR/indirect.rs:5:13: 5:29
-+         _1 = const 3u8;                  // scope 0 at $DIR/indirect.rs:5:13: 5:29
++         _1 = const 3_u8;                 // scope 0 at $DIR/indirect.rs:5:13: 5:29
 +                                          // ty::Const
 +                                          // + ty: u8
 +                                          // + val: Value(Scalar(0x03))

src/test/mir-opt/const_prop/issue-66971/rustc.main.ConstProp.diff

@@ -19,7 +19,7 @@
 +                                          // mir::Constant
 +                                          // + span: $DIR/issue-66971.rs:16:13: 16:15
 +                                          // + literal: Const { ty: (), val: Value(Scalar(<ZST>)) }
-          _2 = (move _3, const 0u8, const 0u8); // scope 0 at $DIR/issue-66971.rs:16:12: 16:22
+          _2 = (move _3, const 0_u8, const 0_u8); // scope 0 at $DIR/issue-66971.rs:16:12: 16:22
                                            // ty::Const
                                            // + ty: u8
                                            // + val: Value(Scalar(0x00))

src/test/mir-opt/const_prop/issue-67019/rustc.main.ConstProp.diff

@@ -11,7 +11,7 @@
           StorageLive(_1);                 // scope 0 at $DIR/issue-67019.rs:11:5: 11:20
           StorageLive(_2);                 // scope 0 at $DIR/issue-67019.rs:11:10: 11:19
           StorageLive(_3);                 // scope 0 at $DIR/issue-67019.rs:11:11: 11:17
-          _3 = (const 1u8, const 2u8);     // scope 0 at $DIR/issue-67019.rs:11:11: 11:17
+          _3 = (const 1_u8, const 2_u8);   // scope 0 at $DIR/issue-67019.rs:11:11: 11:17
                                            // ty::Const
                                            // + ty: u8
                                            // + val: Value(Scalar(0x01))

src/test/mir-opt/const_prop/mutable_variable/rustc.main.ConstProp.diff

@@ -14,14 +14,14 @@
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/mutable_variable.rs:5:9: 5:14
-          _1 = const 42i32;                // scope 0 at $DIR/mutable_variable.rs:5:17: 5:19
+          _1 = const 42_i32;               // scope 0 at $DIR/mutable_variable.rs:5:17: 5:19
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x0000002a))
                                            // mir::Constant
                                            // + span: $DIR/mutable_variable.rs:5:17: 5:19
                                            // + literal: Const { ty: i32, val: Value(Scalar(0x0000002a)) }
-          _1 = const 99i32;                // scope 1 at $DIR/mutable_variable.rs:6:5: 6:11
+          _1 = const 99_i32;               // scope 1 at $DIR/mutable_variable.rs:6:5: 6:11
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x00000063))
@@ -30,7 +30,7 @@
                                            // + literal: Const { ty: i32, val: Value(Scalar(0x00000063)) }
           StorageLive(_2);                 // scope 1 at $DIR/mutable_variable.rs:7:9: 7:10
 -         _2 = _1;                         // scope 1 at $DIR/mutable_variable.rs:7:13: 7:14
-+         _2 = const 99i32;                // scope 1 at $DIR/mutable_variable.rs:7:13: 7:14
++         _2 = const 99_i32;               // scope 1 at $DIR/mutable_variable.rs:7:13: 7:14
 +                                          // ty::Const
 +                                          // + ty: i32
 +                                          // + val: Value(Scalar(0x00000063))

src/test/mir-opt/const_prop/mutable_variable_aggregate/rustc.main.ConstProp.diff

@@ -14,7 +14,7 @@
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/mutable_variable_aggregate.rs:5:9: 5:14
-          _1 = (const 42i32, const 43i32); // scope 0 at $DIR/mutable_variable_aggregate.rs:5:17: 5:25
+          _1 = (const 42_i32, const 43_i32); // scope 0 at $DIR/mutable_variable_aggregate.rs:5:17: 5:25
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x0000002a))
@@ -29,7 +29,7 @@
 -                                          // + span: $DIR/mutable_variable_aggregate.rs:5:22: 5:24
 +                                          // + span: $DIR/mutable_variable_aggregate.rs:5:17: 5:25
                                            // + literal: Const { ty: i32, val: Value(Scalar(0x0000002b)) }
-          (_1.1: i32) = const 99i32;       // scope 1 at $DIR/mutable_variable_aggregate.rs:6:5: 6:13
+          (_1.1: i32) = const 99_i32;      // scope 1 at $DIR/mutable_variable_aggregate.rs:6:5: 6:13
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x00000063))
@@ -38,7 +38,7 @@
                                            // + literal: Const { ty: i32, val: Value(Scalar(0x00000063)) }
           StorageLive(_2);                 // scope 1 at $DIR/mutable_variable_aggregate.rs:7:9: 7:10
 -         _2 = _1;                         // scope 1 at $DIR/mutable_variable_aggregate.rs:7:13: 7:14
-+         _2 = (const 42i32, const 99i32); // scope 1 at $DIR/mutable_variable_aggregate.rs:7:13: 7:14
++         _2 = (const 42_i32, const 99_i32); // scope 1 at $DIR/mutable_variable_aggregate.rs:7:13: 7:14
 +                                          // ty::Const
 +                                          // + ty: i32
 +                                          // + val: Value(Scalar(0x0000002a))

src/test/mir-opt/const_prop/mutable_variable_aggregate_mut_ref/rustc.main.ConstProp.diff

@@ -18,7 +18,7 @@
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/mutable_variable_aggregate_mut_ref.rs:5:9: 5:14
-          _1 = (const 42i32, const 43i32); // scope 0 at $DIR/mutable_variable_aggregate_mut_ref.rs:5:17: 5:25
+          _1 = (const 42_i32, const 43_i32); // scope 0 at $DIR/mutable_variable_aggregate_mut_ref.rs:5:17: 5:25
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x0000002a))
@@ -35,7 +35,7 @@
                                            // + literal: Const { ty: i32, val: Value(Scalar(0x0000002b)) }
           StorageLive(_2);                 // scope 1 at $DIR/mutable_variable_aggregate_mut_ref.rs:6:9: 6:10
           _2 = &mut _1;                    // scope 1 at $DIR/mutable_variable_aggregate_mut_ref.rs:6:13: 6:19
-          ((*_2).1: i32) = const 99i32;    // scope 2 at $DIR/mutable_variable_aggregate_mut_ref.rs:7:5: 7:13
+          ((*_2).1: i32) = const 99_i32;   // scope 2 at $DIR/mutable_variable_aggregate_mut_ref.rs:7:5: 7:13
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x00000063))

src/test/mir-opt/const_prop/mutable_variable_aggregate_partial_read/rustc.main.ConstProp.diff

@@ -24,14 +24,14 @@
       }
   
       bb1: {
-          (_1.1: i32) = const 99i32;       // scope 1 at $DIR/mutable_variable_aggregate_partial_read.rs:6:5: 6:13
+          (_1.1: i32) = const 99_i32;      // scope 1 at $DIR/mutable_variable_aggregate_partial_read.rs:6:5: 6:13
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x00000063))
                                            // mir::Constant
                                            // + span: $DIR/mutable_variable_aggregate_partial_read.rs:6:11: 6:13
                                            // + literal: Const { ty: i32, val: Value(Scalar(0x00000063)) }
-          (_1.0: i32) = const 42i32;       // scope 1 at $DIR/mutable_variable_aggregate_partial_read.rs:7:5: 7:13
+          (_1.0: i32) = const 42_i32;      // scope 1 at $DIR/mutable_variable_aggregate_partial_read.rs:7:5: 7:13
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x0000002a))
@@ -40,7 +40,7 @@
                                            // + literal: Const { ty: i32, val: Value(Scalar(0x0000002a)) }
           StorageLive(_2);                 // scope 1 at $DIR/mutable_variable_aggregate_partial_read.rs:8:9: 8:10
 -         _2 = (_1.1: i32);                // scope 1 at $DIR/mutable_variable_aggregate_partial_read.rs:8:13: 8:16
-+         _2 = const 99i32;                // scope 1 at $DIR/mutable_variable_aggregate_partial_read.rs:8:13: 8:16
++         _2 = const 99_i32;               // scope 1 at $DIR/mutable_variable_aggregate_partial_read.rs:8:13: 8:16
 +                                          // ty::Const
 +                                          // + ty: i32
 +                                          // + val: Value(Scalar(0x00000063))

src/test/mir-opt/const_prop/mutable_variable_no_prop/rustc.main.ConstProp.diff

@@ -19,7 +19,7 @@
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/mutable_variable_no_prop.rs:7:9: 7:14
-          _1 = const 42u32;                // scope 0 at $DIR/mutable_variable_no_prop.rs:7:17: 7:19
+          _1 = const 42_u32;               // scope 0 at $DIR/mutable_variable_no_prop.rs:7:17: 7:19
                                            // ty::Const
                                            // + ty: u32
                                            // + val: Value(Scalar(0x0000002a))

src/test/mir-opt/const_prop/mutable_variable_unprop_assign/rustc.main.ConstProp.diff

@@ -34,7 +34,7 @@
   
       bb1: {
           StorageLive(_2);                 // scope 1 at $DIR/mutable_variable_unprop_assign.rs:6:9: 6:14
-          _2 = (const 1i32, const 2i32);   // scope 1 at $DIR/mutable_variable_unprop_assign.rs:6:29: 6:35
+          _2 = (const 1_i32, const 2_i32); // scope 1 at $DIR/mutable_variable_unprop_assign.rs:6:29: 6:35
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x00000001))

src/test/mir-opt/const_prop/optimizes_into_variable/32bit/rustc.main.ConstProp.diff

@@ -24,8 +24,8 @@
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/optimizes_into_variable.rs:12:9: 12:10
--         _2 = CheckedAdd(const 2i32, const 2i32); // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
-+         _2 = (const 4i32, const false);  // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
+-         _2 = CheckedAdd(const 2_i32, const 2_i32); // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
++         _2 = (const 4_i32, const false); // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
                                            // ty::Const
                                            // + ty: i32
 -                                          // + val: Value(Scalar(0x00000002))
@@ -43,21 +43,33 @@
                                            // mir::Constant
 -                                          // + span: $DIR/optimizes_into_variable.rs:12:17: 12:18
 -                                          // + literal: Const { ty: i32, val: Value(Scalar(0x00000002)) }
--         assert(!move (_2.1: bool), "attempt to add with overflow") -> bb1; // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
+-         assert(!move (_2.1: bool), "attempt to compute `{} + {}` which would overflow", const 2_i32, const 2_i32) -> bb1; // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
 +                                          // + span: $DIR/optimizes_into_variable.rs:12:13: 12:18
 +                                          // + literal: Const { ty: bool, val: Value(Scalar(0x00)) }
-+         assert(!const false, "attempt to add with overflow") -> bb1; // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
-+                                          // ty::Const
++         assert(!const false, "attempt to compute `{} + {}` which would overflow", const 2_i32, const 2_i32) -> bb1; // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
+                                           // ty::Const
 +                                          // + ty: bool
 +                                          // + val: Value(Scalar(0x00))
 +                                          // mir::Constant
 +                                          // + span: $DIR/optimizes_into_variable.rs:12:13: 12:18
 +                                          // + literal: Const { ty: bool, val: Value(Scalar(0x00)) }
++                                          // ty::Const
+                                           // + ty: i32
+                                           // + val: Value(Scalar(0x00000002))
+                                           // mir::Constant
+                                           // + span: $DIR/optimizes_into_variable.rs:12:13: 12:14
+                                           // + literal: Const { ty: i32, val: Value(Scalar(0x00000002)) }
+                                           // ty::Const
+                                           // + ty: i32
+                                           // + val: Value(Scalar(0x00000002))
+                                           // mir::Constant
+                                           // + span: $DIR/optimizes_into_variable.rs:12:17: 12:18
+                                           // + literal: Const { ty: i32, val: Value(Scalar(0x00000002)) }
       }
   
       bb1: {
 -         _1 = move (_2.0: i32);           // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
-+         _1 = const 4i32;                 // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
++         _1 = const 4_i32;                // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
 +                                          // ty::Const
 +                                          // + ty: i32
 +                                          // + val: Value(Scalar(0x00000004))
@@ -66,7 +78,7 @@
 +                                          // + literal: Const { ty: i32, val: Value(Scalar(0x00000004)) }
           StorageLive(_3);                 // scope 1 at $DIR/optimizes_into_variable.rs:13:9: 13:10
           StorageLive(_4);                 // scope 1 at $DIR/optimizes_into_variable.rs:13:13: 13:31
-          _4 = [const 0i32, const 1i32, const 2i32, const 3i32, const 4i32, const 5i32]; // scope 1 at $DIR/optimizes_into_variable.rs:13:13: 13:31
+          _4 = [const 0_i32, const 1_i32, const 2_i32, const 3_i32, const 4_i32, const 5_i32]; // scope 1 at $DIR/optimizes_into_variable.rs:13:13: 13:31
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x00000000))
@@ -104,14 +116,14 @@
                                            // + span: $DIR/optimizes_into_variable.rs:13:29: 13:30
                                            // + literal: Const { ty: i32, val: Value(Scalar(0x00000005)) }
           StorageLive(_5);                 // scope 1 at $DIR/optimizes_into_variable.rs:13:32: 13:33
-          _5 = const 3usize;               // scope 1 at $DIR/optimizes_into_variable.rs:13:32: 13:33
+          _5 = const 3_usize;              // scope 1 at $DIR/optimizes_into_variable.rs:13:32: 13:33
                                            // ty::Const
                                            // + ty: usize
                                            // + val: Value(Scalar(0x00000003))
                                            // mir::Constant
                                            // + span: $DIR/optimizes_into_variable.rs:13:32: 13:33
                                            // + literal: Const { ty: usize, val: Value(Scalar(0x00000003)) }
-          _6 = const 6usize;               // scope 1 at $DIR/optimizes_into_variable.rs:13:13: 13:34
+          _6 = const 6_usize;              // scope 1 at $DIR/optimizes_into_variable.rs:13:13: 13:34
                                            // ty::Const
                                            // + ty: usize
                                            // + val: Value(Scalar(0x00000006))
@@ -138,7 +150,7 @@
   
       bb2: {
 -         _3 = _4[_5];                     // scope 1 at $DIR/optimizes_into_variable.rs:13:13: 13:34
-+         _3 = const 3i32;                 // scope 1 at $DIR/optimizes_into_variable.rs:13:13: 13:34
++         _3 = const 3_i32;                // scope 1 at $DIR/optimizes_into_variable.rs:13:13: 13:34
 +                                          // ty::Const
 +                                          // + ty: i32
 +                                          // + val: Value(Scalar(0x00000003))
@@ -149,7 +161,7 @@
           StorageDead(_4);                 // scope 1 at $DIR/optimizes_into_variable.rs:13:34: 13:35
           StorageLive(_8);                 // scope 2 at $DIR/optimizes_into_variable.rs:14:9: 14:10
           StorageLive(_9);                 // scope 2 at $DIR/optimizes_into_variable.rs:14:13: 14:36
-          _9 = Point { x: const 12u32, y: const 42u32 }; // scope 2 at $DIR/optimizes_into_variable.rs:14:13: 14:36
+          _9 = Point { x: const 12_u32, y: const 42_u32 }; // scope 2 at $DIR/optimizes_into_variable.rs:14:13: 14:36
                                            // ty::Const
                                            // + ty: u32
                                            // + val: Value(Scalar(0x0000000c))
@@ -163,7 +175,7 @@
                                            // + span: $DIR/optimizes_into_variable.rs:14:32: 14:34
                                            // + literal: Const { ty: u32, val: Value(Scalar(0x0000002a)) }
 -         _8 = (_9.1: u32);                // scope 2 at $DIR/optimizes_into_variable.rs:14:13: 14:38
-+         _8 = const 42u32;                // scope 2 at $DIR/optimizes_into_variable.rs:14:13: 14:38
++         _8 = const 42_u32;               // scope 2 at $DIR/optimizes_into_variable.rs:14:13: 14:38
 +                                          // ty::Const
 +                                          // + ty: u32
 +                                          // + val: Value(Scalar(0x0000002a))

src/test/mir-opt/const_prop/optimizes_into_variable/32bit/rustc.main.SimplifyLocals.after.mir

@@ -17,7 +17,7 @@ fn main() -> () {
 
     bb0: {
         StorageLive(_1);                 // scope 0 at $DIR/optimizes_into_variable.rs:12:9: 12:10
-        _1 = const 4i32;                 // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
+        _1 = const 4_i32;                // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000004))
@@ -25,7 +25,7 @@ fn main() -> () {
                                          // + span: $DIR/optimizes_into_variable.rs:12:13: 12:18
                                          // + literal: Const { ty: i32, val: Value(Scalar(0x00000004)) }
         StorageLive(_2);                 // scope 1 at $DIR/optimizes_into_variable.rs:13:9: 13:10
-        _2 = const 3i32;                 // scope 1 at $DIR/optimizes_into_variable.rs:13:13: 13:34
+        _2 = const 3_i32;                // scope 1 at $DIR/optimizes_into_variable.rs:13:13: 13:34
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000003))
@@ -33,7 +33,7 @@ fn main() -> () {
                                          // + span: $DIR/optimizes_into_variable.rs:13:13: 13:34
                                          // + literal: Const { ty: i32, val: Value(Scalar(0x00000003)) }
         StorageLive(_3);                 // scope 2 at $DIR/optimizes_into_variable.rs:14:9: 14:10
-        _3 = const 42u32;                // scope 2 at $DIR/optimizes_into_variable.rs:14:13: 14:38
+        _3 = const 42_u32;               // scope 2 at $DIR/optimizes_into_variable.rs:14:13: 14:38
                                          // ty::Const
                                          // + ty: u32
                                          // + val: Value(Scalar(0x0000002a))

src/test/mir-opt/const_prop/optimizes_into_variable/64bit/rustc.main.ConstProp.diff

@@ -24,8 +24,8 @@
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/optimizes_into_variable.rs:12:9: 12:10
--         _2 = CheckedAdd(const 2i32, const 2i32); // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
-+         _2 = (const 4i32, const false);  // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
+-         _2 = CheckedAdd(const 2_i32, const 2_i32); // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
++         _2 = (const 4_i32, const false); // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
                                            // ty::Const
                                            // + ty: i32
 -                                          // + val: Value(Scalar(0x00000002))
@@ -43,21 +43,33 @@
                                            // mir::Constant
 -                                          // + span: $DIR/optimizes_into_variable.rs:12:17: 12:18
 -                                          // + literal: Const { ty: i32, val: Value(Scalar(0x00000002)) }
--         assert(!move (_2.1: bool), "attempt to add with overflow") -> bb1; // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
+-         assert(!move (_2.1: bool), "attempt to compute `{} + {}` which would overflow", const 2_i32, const 2_i32) -> bb1; // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
 +                                          // + span: $DIR/optimizes_into_variable.rs:12:13: 12:18
 +                                          // + literal: Const { ty: bool, val: Value(Scalar(0x00)) }
-+         assert(!const false, "attempt to add with overflow") -> bb1; // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
-+                                          // ty::Const
++         assert(!const false, "attempt to compute `{} + {}` which would overflow", const 2_i32, const 2_i32) -> bb1; // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
+                                           // ty::Const
 +                                          // + ty: bool
 +                                          // + val: Value(Scalar(0x00))
 +                                          // mir::Constant
 +                                          // + span: $DIR/optimizes_into_variable.rs:12:13: 12:18
 +                                          // + literal: Const { ty: bool, val: Value(Scalar(0x00)) }
++                                          // ty::Const
+                                           // + ty: i32
+                                           // + val: Value(Scalar(0x00000002))
+                                           // mir::Constant
+                                           // + span: $DIR/optimizes_into_variable.rs:12:13: 12:14
+                                           // + literal: Const { ty: i32, val: Value(Scalar(0x00000002)) }
+                                           // ty::Const
+                                           // + ty: i32
+                                           // + val: Value(Scalar(0x00000002))
+                                           // mir::Constant
+                                           // + span: $DIR/optimizes_into_variable.rs:12:17: 12:18
+                                           // + literal: Const { ty: i32, val: Value(Scalar(0x00000002)) }
       }
   
       bb1: {
 -         _1 = move (_2.0: i32);           // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
-+         _1 = const 4i32;                 // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
++         _1 = const 4_i32;                // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
 +                                          // ty::Const
 +                                          // + ty: i32
 +                                          // + val: Value(Scalar(0x00000004))
@@ -66,7 +78,7 @@
 +                                          // + literal: Const { ty: i32, val: Value(Scalar(0x00000004)) }
           StorageLive(_3);                 // scope 1 at $DIR/optimizes_into_variable.rs:13:9: 13:10
           StorageLive(_4);                 // scope 1 at $DIR/optimizes_into_variable.rs:13:13: 13:31
-          _4 = [const 0i32, const 1i32, const 2i32, const 3i32, const 4i32, const 5i32]; // scope 1 at $DIR/optimizes_into_variable.rs:13:13: 13:31
+          _4 = [const 0_i32, const 1_i32, const 2_i32, const 3_i32, const 4_i32, const 5_i32]; // scope 1 at $DIR/optimizes_into_variable.rs:13:13: 13:31
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x00000000))
@@ -104,14 +116,14 @@
                                            // + span: $DIR/optimizes_into_variable.rs:13:29: 13:30
                                            // + literal: Const { ty: i32, val: Value(Scalar(0x00000005)) }
           StorageLive(_5);                 // scope 1 at $DIR/optimizes_into_variable.rs:13:32: 13:33
-          _5 = const 3usize;               // scope 1 at $DIR/optimizes_into_variable.rs:13:32: 13:33
+          _5 = const 3_usize;              // scope 1 at $DIR/optimizes_into_variable.rs:13:32: 13:33
                                            // ty::Const
                                            // + ty: usize
                                            // + val: Value(Scalar(0x0000000000000003))
                                            // mir::Constant
                                            // + span: $DIR/optimizes_into_variable.rs:13:32: 13:33
                                            // + literal: Const { ty: usize, val: Value(Scalar(0x0000000000000003)) }
-          _6 = const 6usize;               // scope 1 at $DIR/optimizes_into_variable.rs:13:13: 13:34
+          _6 = const 6_usize;              // scope 1 at $DIR/optimizes_into_variable.rs:13:13: 13:34
                                            // ty::Const
                                            // + ty: usize
                                            // + val: Value(Scalar(0x0000000000000006))
@@ -138,7 +150,7 @@
   
       bb2: {
 -         _3 = _4[_5];                     // scope 1 at $DIR/optimizes_into_variable.rs:13:13: 13:34
-+         _3 = const 3i32;                 // scope 1 at $DIR/optimizes_into_variable.rs:13:13: 13:34
++         _3 = const 3_i32;                // scope 1 at $DIR/optimizes_into_variable.rs:13:13: 13:34
 +                                          // ty::Const
 +                                          // + ty: i32
 +                                          // + val: Value(Scalar(0x00000003))
@@ -149,7 +161,7 @@
           StorageDead(_4);                 // scope 1 at $DIR/optimizes_into_variable.rs:13:34: 13:35
           StorageLive(_8);                 // scope 2 at $DIR/optimizes_into_variable.rs:14:9: 14:10
           StorageLive(_9);                 // scope 2 at $DIR/optimizes_into_variable.rs:14:13: 14:36
-          _9 = Point { x: const 12u32, y: const 42u32 }; // scope 2 at $DIR/optimizes_into_variable.rs:14:13: 14:36
+          _9 = Point { x: const 12_u32, y: const 42_u32 }; // scope 2 at $DIR/optimizes_into_variable.rs:14:13: 14:36
                                            // ty::Const
                                            // + ty: u32
                                            // + val: Value(Scalar(0x0000000c))
@@ -163,7 +175,7 @@
                                            // + span: $DIR/optimizes_into_variable.rs:14:32: 14:34
                                            // + literal: Const { ty: u32, val: Value(Scalar(0x0000002a)) }
 -         _8 = (_9.1: u32);                // scope 2 at $DIR/optimizes_into_variable.rs:14:13: 14:38
-+         _8 = const 42u32;                // scope 2 at $DIR/optimizes_into_variable.rs:14:13: 14:38
++         _8 = const 42_u32;               // scope 2 at $DIR/optimizes_into_variable.rs:14:13: 14:38
 +                                          // ty::Const
 +                                          // + ty: u32
 +                                          // + val: Value(Scalar(0x0000002a))

src/test/mir-opt/const_prop/optimizes_into_variable/64bit/rustc.main.SimplifyLocals.after.mir

@@ -17,7 +17,7 @@ fn main() -> () {
 
     bb0: {
         StorageLive(_1);                 // scope 0 at $DIR/optimizes_into_variable.rs:12:9: 12:10
-        _1 = const 4i32;                 // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
+        _1 = const 4_i32;                // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000004))
@@ -25,7 +25,7 @@ fn main() -> () {
                                          // + span: $DIR/optimizes_into_variable.rs:12:13: 12:18
                                          // + literal: Const { ty: i32, val: Value(Scalar(0x00000004)) }
         StorageLive(_2);                 // scope 1 at $DIR/optimizes_into_variable.rs:13:9: 13:10
-        _2 = const 3i32;                 // scope 1 at $DIR/optimizes_into_variable.rs:13:13: 13:34
+        _2 = const 3_i32;                // scope 1 at $DIR/optimizes_into_variable.rs:13:13: 13:34
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000003))
@@ -33,7 +33,7 @@ fn main() -> () {
                                          // + span: $DIR/optimizes_into_variable.rs:13:13: 13:34
                                          // + literal: Const { ty: i32, val: Value(Scalar(0x00000003)) }
         StorageLive(_3);                 // scope 2 at $DIR/optimizes_into_variable.rs:14:9: 14:10
-        _3 = const 42u32;                // scope 2 at $DIR/optimizes_into_variable.rs:14:13: 14:38
+        _3 = const 42_u32;               // scope 2 at $DIR/optimizes_into_variable.rs:14:13: 14:38
                                          // ty::Const
                                          // + ty: u32
                                          // + val: Value(Scalar(0x0000002a))

src/test/mir-opt/const_prop/read_immutable_static/rustc.main.ConstProp.diff

@@ -24,7 +24,7 @@
                                            // + span: $DIR/read_immutable_static.rs:7:13: 7:16
                                            // + literal: Const { ty: &u8, val: Value(Scalar(alloc0)) }
 -         _2 = (*_3);                      // scope 0 at $DIR/read_immutable_static.rs:7:13: 7:16
-+         _2 = const 2u8;                  // scope 0 at $DIR/read_immutable_static.rs:7:13: 7:16
++         _2 = const 2_u8;                 // scope 0 at $DIR/read_immutable_static.rs:7:13: 7:16
 +                                          // ty::Const
 +                                          // + ty: u8
 +                                          // + val: Value(Scalar(0x02))
@@ -42,14 +42,14 @@
                                            // + literal: Const { ty: &u8, val: Value(Scalar(alloc0)) }
 -         _4 = (*_5);                      // scope 0 at $DIR/read_immutable_static.rs:7:19: 7:22
 -         _1 = Add(move _2, move _4);      // scope 0 at $DIR/read_immutable_static.rs:7:13: 7:22
-+         _4 = const 2u8;                  // scope 0 at $DIR/read_immutable_static.rs:7:19: 7:22
++         _4 = const 2_u8;                 // scope 0 at $DIR/read_immutable_static.rs:7:19: 7:22
 +                                          // ty::Const
 +                                          // + ty: u8
 +                                          // + val: Value(Scalar(0x02))
 +                                          // mir::Constant
 +                                          // + span: $DIR/read_immutable_static.rs:7:19: 7:22
 +                                          // + literal: Const { ty: u8, val: Value(Scalar(0x02)) }
-+         _1 = const 4u8;                  // scope 0 at $DIR/read_immutable_static.rs:7:13: 7:22
++         _1 = const 4_u8;                 // scope 0 at $DIR/read_immutable_static.rs:7:13: 7:22
 +                                          // ty::Const
 +                                          // + ty: u8
 +                                          // + val: Value(Scalar(0x04))

src/test/mir-opt/const_prop/ref_deref/rustc.main.ConstProp.diff

@@ -20,7 +20,7 @@
                                            // + literal: Const { ty: &i32, val: Unevaluated(DefId(0:3 ~ ref_deref[317d]::main[0]), [], Some(promoted[0])) }
           _2 = _4;                         // scope 0 at $DIR/ref_deref.rs:5:6: 5:10
 -         _1 = (*_2);                      // scope 0 at $DIR/ref_deref.rs:5:5: 5:10
-+         _1 = const 4i32;                 // scope 0 at $DIR/ref_deref.rs:5:5: 5:10
++         _1 = const 4_i32;                // scope 0 at $DIR/ref_deref.rs:5:5: 5:10
 +                                          // ty::Const
 +                                          // + ty: i32
 +                                          // + val: Value(Scalar(0x00000004))

src/test/mir-opt/const_prop/ref_deref/rustc.main.PromoteTemps.diff

@@ -12,7 +12,7 @@
           StorageLive(_1);                 // scope 0 at $DIR/ref_deref.rs:5:5: 5:10
           StorageLive(_2);                 // scope 0 at $DIR/ref_deref.rs:5:6: 5:10
 -         StorageLive(_3);                 // scope 0 at $DIR/ref_deref.rs:5:8: 5:9
--         _3 = const 4i32;                 // scope 0 at $DIR/ref_deref.rs:5:8: 5:9
+-         _3 = const 4_i32;                // scope 0 at $DIR/ref_deref.rs:5:8: 5:9
 +         _4 = const main::promoted[0];    // scope 0 at $DIR/ref_deref.rs:5:6: 5:10
                                            // ty::Const
 -                                          // + ty: i32

src/test/mir-opt/const_prop/ref_deref_project/rustc.main.PromoteTemps.diff

@@ -12,7 +12,7 @@
           StorageLive(_1);                 // scope 0 at $DIR/ref_deref_project.rs:5:5: 5:17
           StorageLive(_2);                 // scope 0 at $DIR/ref_deref_project.rs:5:6: 5:17
 -         StorageLive(_3);                 // scope 0 at $DIR/ref_deref_project.rs:5:8: 5:14
--         _3 = (const 4i32, const 5i32);   // scope 0 at $DIR/ref_deref_project.rs:5:8: 5:14
+-         _3 = (const 4_i32, const 5_i32); // scope 0 at $DIR/ref_deref_project.rs:5:8: 5:14
 +         _4 = const main::promoted[0];    // scope 0 at $DIR/ref_deref_project.rs:5:6: 5:17
                                            // ty::Const
 -                                          // + ty: i32

src/test/mir-opt/const_prop/repeat/32bit/rustc.main.ConstProp.diff

@@ -17,7 +17,7 @@
           StorageLive(_1);                 // scope 0 at $DIR/repeat.rs:6:9: 6:10
           StorageLive(_2);                 // scope 0 at $DIR/repeat.rs:6:18: 6:28
           StorageLive(_3);                 // scope 0 at $DIR/repeat.rs:6:18: 6:25
-          _3 = [const 42u32; 8];           // scope 0 at $DIR/repeat.rs:6:18: 6:25
+          _3 = [const 42_u32; 8];          // scope 0 at $DIR/repeat.rs:6:18: 6:25
                                            // ty::Const
                                            // + ty: u32
                                            // + val: Value(Scalar(0x0000002a))
@@ -25,14 +25,14 @@
                                            // + span: $DIR/repeat.rs:6:19: 6:21
                                            // + literal: Const { ty: u32, val: Value(Scalar(0x0000002a)) }
           StorageLive(_4);                 // scope 0 at $DIR/repeat.rs:6:26: 6:27
-          _4 = const 2usize;               // scope 0 at $DIR/repeat.rs:6:26: 6:27
+          _4 = const 2_usize;              // scope 0 at $DIR/repeat.rs:6:26: 6:27
                                            // ty::Const
                                            // + ty: usize
                                            // + val: Value(Scalar(0x00000002))
                                            // mir::Constant
                                            // + span: $DIR/repeat.rs:6:26: 6:27
                                            // + literal: Const { ty: usize, val: Value(Scalar(0x00000002)) }
-          _5 = const 8usize;               // scope 0 at $DIR/repeat.rs:6:18: 6:28
+          _5 = const 8_usize;              // scope 0 at $DIR/repeat.rs:6:18: 6:28
                                            // ty::Const
                                            // + ty: usize
                                            // + val: Value(Scalar(0x00000008))
@@ -59,8 +59,8 @@
   
       bb1: {
 -         _2 = _3[_4];                     // scope 0 at $DIR/repeat.rs:6:18: 6:28
--         _1 = Add(move _2, const 0u32);   // scope 0 at $DIR/repeat.rs:6:18: 6:32
-+         _2 = const 42u32;                // scope 0 at $DIR/repeat.rs:6:18: 6:28
+-         _1 = Add(move _2, const 0_u32);  // scope 0 at $DIR/repeat.rs:6:18: 6:32
++         _2 = const 42_u32;               // scope 0 at $DIR/repeat.rs:6:18: 6:28
                                            // ty::Const
                                            // + ty: u32
 -                                          // + val: Value(Scalar(0x00000000))
@@ -70,7 +70,7 @@
 -                                          // + literal: Const { ty: u32, val: Value(Scalar(0x00000000)) }
 +                                          // + span: $DIR/repeat.rs:6:18: 6:28
 +                                          // + literal: Const { ty: u32, val: Value(Scalar(0x0000002a)) }
-+         _1 = const 42u32;                // scope 0 at $DIR/repeat.rs:6:18: 6:32
++         _1 = const 42_u32;               // scope 0 at $DIR/repeat.rs:6:18: 6:32
 +                                          // ty::Const
 +                                          // + ty: u32
 +                                          // + val: Value(Scalar(0x0000002a))

src/test/mir-opt/const_prop/repeat/64bit/rustc.main.ConstProp.diff

@@ -17,7 +17,7 @@
           StorageLive(_1);                 // scope 0 at $DIR/repeat.rs:6:9: 6:10
           StorageLive(_2);                 // scope 0 at $DIR/repeat.rs:6:18: 6:28
           StorageLive(_3);                 // scope 0 at $DIR/repeat.rs:6:18: 6:25
-          _3 = [const 42u32; 8];           // scope 0 at $DIR/repeat.rs:6:18: 6:25
+          _3 = [const 42_u32; 8];          // scope 0 at $DIR/repeat.rs:6:18: 6:25
                                            // ty::Const
                                            // + ty: u32
                                            // + val: Value(Scalar(0x0000002a))
@@ -25,14 +25,14 @@
                                            // + span: $DIR/repeat.rs:6:19: 6:21
                                            // + literal: Const { ty: u32, val: Value(Scalar(0x0000002a)) }
           StorageLive(_4);                 // scope 0 at $DIR/repeat.rs:6:26: 6:27
-          _4 = const 2usize;               // scope 0 at $DIR/repeat.rs:6:26: 6:27
+          _4 = const 2_usize;              // scope 0 at $DIR/repeat.rs:6:26: 6:27
                                            // ty::Const
                                            // + ty: usize
                                            // + val: Value(Scalar(0x0000000000000002))
                                            // mir::Constant
                                            // + span: $DIR/repeat.rs:6:26: 6:27
                                            // + literal: Const { ty: usize, val: Value(Scalar(0x0000000000000002)) }
-          _5 = const 8usize;               // scope 0 at $DIR/repeat.rs:6:18: 6:28
+          _5 = const 8_usize;              // scope 0 at $DIR/repeat.rs:6:18: 6:28
                                            // ty::Const
                                            // + ty: usize
                                            // + val: Value(Scalar(0x0000000000000008))
@@ -59,8 +59,8 @@
   
       bb1: {
 -         _2 = _3[_4];                     // scope 0 at $DIR/repeat.rs:6:18: 6:28
--         _1 = Add(move _2, const 0u32);   // scope 0 at $DIR/repeat.rs:6:18: 6:32
-+         _2 = const 42u32;                // scope 0 at $DIR/repeat.rs:6:18: 6:28
+-         _1 = Add(move _2, const 0_u32);  // scope 0 at $DIR/repeat.rs:6:18: 6:32
++         _2 = const 42_u32;               // scope 0 at $DIR/repeat.rs:6:18: 6:28
                                            // ty::Const
                                            // + ty: u32
 -                                          // + val: Value(Scalar(0x00000000))
@@ -70,7 +70,7 @@
 -                                          // + literal: Const { ty: u32, val: Value(Scalar(0x00000000)) }
 +                                          // + span: $DIR/repeat.rs:6:18: 6:28
 +                                          // + literal: Const { ty: u32, val: Value(Scalar(0x0000002a)) }
-+         _1 = const 42u32;                // scope 0 at $DIR/repeat.rs:6:18: 6:32
++         _1 = const 42_u32;               // scope 0 at $DIR/repeat.rs:6:18: 6:32
 +                                          // ty::Const
 +                                          // + ty: u32
 +                                          // + val: Value(Scalar(0x0000002a))

src/test/mir-opt/const_prop/return_place/rustc.add.ConstProp.diff

@@ -6,8 +6,8 @@
       let mut _1: (u32, bool);             // in scope 0 at $DIR/return_place.rs:6:5: 6:10
   
       bb0: {
--         _1 = CheckedAdd(const 2u32, const 2u32); // scope 0 at $DIR/return_place.rs:6:5: 6:10
-+         _1 = (const 4u32, const false);  // scope 0 at $DIR/return_place.rs:6:5: 6:10
+-         _1 = CheckedAdd(const 2_u32, const 2_u32); // scope 0 at $DIR/return_place.rs:6:5: 6:10
++         _1 = (const 4_u32, const false); // scope 0 at $DIR/return_place.rs:6:5: 6:10
                                            // ty::Const
                                            // + ty: u32
 -                                          // + val: Value(Scalar(0x00000002))
@@ -25,21 +25,33 @@
                                            // mir::Constant
 -                                          // + span: $DIR/return_place.rs:6:9: 6:10
 -                                          // + literal: Const { ty: u32, val: Value(Scalar(0x00000002)) }
--         assert(!move (_1.1: bool), "attempt to add with overflow") -> bb1; // scope 0 at $DIR/return_place.rs:6:5: 6:10
+-         assert(!move (_1.1: bool), "attempt to compute `{} + {}` which would overflow", const 2_u32, const 2_u32) -> bb1; // scope 0 at $DIR/return_place.rs:6:5: 6:10
 +                                          // + span: $DIR/return_place.rs:6:5: 6:10
 +                                          // + literal: Const { ty: bool, val: Value(Scalar(0x00)) }
-+         assert(!const false, "attempt to add with overflow") -> bb1; // scope 0 at $DIR/return_place.rs:6:5: 6:10
-+                                          // ty::Const
++         assert(!const false, "attempt to compute `{} + {}` which would overflow", const 2_u32, const 2_u32) -> bb1; // scope 0 at $DIR/return_place.rs:6:5: 6:10
+                                           // ty::Const
 +                                          // + ty: bool
 +                                          // + val: Value(Scalar(0x00))
 +                                          // mir::Constant
 +                                          // + span: $DIR/return_place.rs:6:5: 6:10
 +                                          // + literal: Const { ty: bool, val: Value(Scalar(0x00)) }
++                                          // ty::Const
+                                           // + ty: u32
+                                           // + val: Value(Scalar(0x00000002))
+                                           // mir::Constant
+                                           // + span: $DIR/return_place.rs:6:5: 6:6
+                                           // + literal: Const { ty: u32, val: Value(Scalar(0x00000002)) }
+                                           // ty::Const
+                                           // + ty: u32
+                                           // + val: Value(Scalar(0x00000002))
+                                           // mir::Constant
+                                           // + span: $DIR/return_place.rs:6:9: 6:10
+                                           // + literal: Const { ty: u32, val: Value(Scalar(0x00000002)) }
       }
   
       bb1: {
 -         _0 = move (_1.0: u32);           // scope 0 at $DIR/return_place.rs:6:5: 6:10
-+         _0 = const 4u32;                 // scope 0 at $DIR/return_place.rs:6:5: 6:10
++         _0 = const 4_u32;                // scope 0 at $DIR/return_place.rs:6:5: 6:10
 +                                          // ty::Const
 +                                          // + ty: u32
 +                                          // + val: Value(Scalar(0x00000004))

src/test/mir-opt/const_prop/return_place/rustc.add.PreCodegen.before.mir

@@ -4,7 +4,7 @@ fn add() -> u32 {
     let mut _0: u32;                     // return place in scope 0 at $DIR/return_place.rs:5:13: 5:16
 
     bb0: {
-        _0 = const 4u32;                 // scope 0 at $DIR/return_place.rs:6:5: 6:10
+        _0 = const 4_u32;                // scope 0 at $DIR/return_place.rs:6:5: 6:10
                                          // ty::Const
                                          // + ty: u32
                                          // + val: Value(Scalar(0x00000004))

src/test/mir-opt/const_prop/scalar_literal_propagation/rustc.main.ConstProp.diff

@@ -12,7 +12,7 @@
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/scalar_literal_propagation.rs:3:9: 3:10
-          _1 = const 1u32;                 // scope 0 at $DIR/scalar_literal_propagation.rs:3:13: 3:14
+          _1 = const 1_u32;                // scope 0 at $DIR/scalar_literal_propagation.rs:3:13: 3:14
                                            // ty::Const
                                            // + ty: u32
                                            // + val: Value(Scalar(0x00000001))
@@ -23,14 +23,14 @@
           StorageLive(_3);                 // scope 1 at $DIR/scalar_literal_propagation.rs:4:13: 4:14
 -         _3 = _1;                         // scope 1 at $DIR/scalar_literal_propagation.rs:4:13: 4:14
 -         _2 = const consume(move _3) -> bb1; // scope 1 at $DIR/scalar_literal_propagation.rs:4:5: 4:15
-+         _3 = const 1u32;                 // scope 1 at $DIR/scalar_literal_propagation.rs:4:13: 4:14
++         _3 = const 1_u32;                // scope 1 at $DIR/scalar_literal_propagation.rs:4:13: 4:14
                                            // ty::Const
 +                                          // + ty: u32
 +                                          // + val: Value(Scalar(0x00000001))
 +                                          // mir::Constant
 +                                          // + span: $DIR/scalar_literal_propagation.rs:4:13: 4:14
 +                                          // + literal: Const { ty: u32, val: Value(Scalar(0x00000001)) }
-+         _2 = const consume(const 1u32) -> bb1; // scope 1 at $DIR/scalar_literal_propagation.rs:4:5: 4:15
++         _2 = const consume(const 1_u32) -> bb1; // scope 1 at $DIR/scalar_literal_propagation.rs:4:5: 4:15
 +                                          // ty::Const
                                            // + ty: fn(u32) {consume}
                                            // + val: Value(Scalar(<ZST>))

src/test/mir-opt/const_prop/slice_len/32bit/rustc.main.ConstProp.diff

@@ -30,7 +30,7 @@
           _2 = move _3 as &[u32] (Pointer(Unsize)); // scope 0 at $DIR/slice_len.rs:5:6: 5:19
           StorageDead(_3);                 // scope 0 at $DIR/slice_len.rs:5:18: 5:19
           StorageLive(_6);                 // scope 0 at $DIR/slice_len.rs:5:31: 5:32
-          _6 = const 1usize;               // scope 0 at $DIR/slice_len.rs:5:31: 5:32
+          _6 = const 1_usize;              // scope 0 at $DIR/slice_len.rs:5:31: 5:32
                                            // ty::Const
                                            // + ty: usize
                                            // + val: Value(Scalar(0x00000001))
@@ -40,7 +40,7 @@
 -         _7 = Len((*_2));                 // scope 0 at $DIR/slice_len.rs:5:5: 5:33
 -         _8 = Lt(_6, _7);                 // scope 0 at $DIR/slice_len.rs:5:5: 5:33
 -         assert(move _8, "index out of bounds: the len is {} but the index is {}", move _7, _6) -> bb1; // scope 0 at $DIR/slice_len.rs:5:5: 5:33
-+         _7 = const 3usize;               // scope 0 at $DIR/slice_len.rs:5:5: 5:33
++         _7 = const 3_usize;              // scope 0 at $DIR/slice_len.rs:5:5: 5:33
 +                                          // ty::Const
 +                                          // + ty: usize
 +                                          // + val: Value(Scalar(0x00000003))
@@ -65,7 +65,7 @@
   
       bb1: {
 -         _1 = (*_2)[_6];                  // scope 0 at $DIR/slice_len.rs:5:5: 5:33
-+         _1 = const 2u32;                 // scope 0 at $DIR/slice_len.rs:5:5: 5:33
++         _1 = const 2_u32;                // scope 0 at $DIR/slice_len.rs:5:5: 5:33
 +                                          // ty::Const
 +                                          // + ty: u32
 +                                          // + val: Value(Scalar(0x00000002))

src/test/mir-opt/const_prop/slice_len/64bit/rustc.main.ConstProp.diff

@@ -30,7 +30,7 @@
           _2 = move _3 as &[u32] (Pointer(Unsize)); // scope 0 at $DIR/slice_len.rs:5:6: 5:19
           StorageDead(_3);                 // scope 0 at $DIR/slice_len.rs:5:18: 5:19
           StorageLive(_6);                 // scope 0 at $DIR/slice_len.rs:5:31: 5:32
-          _6 = const 1usize;               // scope 0 at $DIR/slice_len.rs:5:31: 5:32
+          _6 = const 1_usize;              // scope 0 at $DIR/slice_len.rs:5:31: 5:32
                                            // ty::Const
                                            // + ty: usize
                                            // + val: Value(Scalar(0x0000000000000001))
@@ -40,7 +40,7 @@
 -         _7 = Len((*_2));                 // scope 0 at $DIR/slice_len.rs:5:5: 5:33
 -         _8 = Lt(_6, _7);                 // scope 0 at $DIR/slice_len.rs:5:5: 5:33
 -         assert(move _8, "index out of bounds: the len is {} but the index is {}", move _7, _6) -> bb1; // scope 0 at $DIR/slice_len.rs:5:5: 5:33
-+         _7 = const 3usize;               // scope 0 at $DIR/slice_len.rs:5:5: 5:33
++         _7 = const 3_usize;              // scope 0 at $DIR/slice_len.rs:5:5: 5:33
 +                                          // ty::Const
 +                                          // + ty: usize
 +                                          // + val: Value(Scalar(0x0000000000000003))
@@ -65,7 +65,7 @@
   
       bb1: {
 -         _1 = (*_2)[_6];                  // scope 0 at $DIR/slice_len.rs:5:5: 5:33
-+         _1 = const 2u32;                 // scope 0 at $DIR/slice_len.rs:5:5: 5:33
++         _1 = const 2_u32;                // scope 0 at $DIR/slice_len.rs:5:5: 5:33
 +                                          // ty::Const
 +                                          // + ty: u32
 +                                          // + val: Value(Scalar(0x00000002))

src/test/mir-opt/const_prop/switch_int/rustc.main.ConstProp.diff

@@ -7,15 +7,15 @@
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/switch_int.rs:7:11: 7:12
-          _1 = const 1i32;                 // scope 0 at $DIR/switch_int.rs:7:11: 7:12
+          _1 = const 1_i32;                // scope 0 at $DIR/switch_int.rs:7:11: 7:12
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x00000001))
                                            // mir::Constant
                                            // + span: $DIR/switch_int.rs:7:11: 7:12
                                            // + literal: Const { ty: i32, val: Value(Scalar(0x00000001)) }
--         switchInt(_1) -> [1i32: bb2, otherwise: bb1]; // scope 0 at $DIR/switch_int.rs:8:9: 8:10
-+         switchInt(const 1i32) -> [1i32: bb2, otherwise: bb1]; // scope 0 at $DIR/switch_int.rs:8:9: 8:10
+-         switchInt(_1) -> [1_i32: bb2, otherwise: bb1]; // scope 0 at $DIR/switch_int.rs:8:9: 8:10
++         switchInt(const 1_i32) -> [1_i32: bb2, otherwise: bb1]; // scope 0 at $DIR/switch_int.rs:8:9: 8:10
 +                                          // ty::Const
 +                                          // + ty: i32
 +                                          // + val: Value(Scalar(0x00000001))
@@ -25,7 +25,7 @@
       }
   
       bb1: {
-          _0 = const foo(const -1i32) -> bb3; // scope 0 at $DIR/switch_int.rs:9:14: 9:21
+          _0 = const foo(const -1_i32) -> bb3; // scope 0 at $DIR/switch_int.rs:9:14: 9:21
                                            // ty::Const
                                            // + ty: fn(i32) {foo}
                                            // + val: Value(Scalar(<ZST>))
@@ -41,7 +41,7 @@
       }
   
       bb2: {
-          _0 = const foo(const 0i32) -> bb3; // scope 0 at $DIR/switch_int.rs:8:14: 8:20
+          _0 = const foo(const 0_i32) -> bb3; // scope 0 at $DIR/switch_int.rs:8:14: 8:20
                                            // ty::Const
                                            // + ty: fn(i32) {foo}
                                            // + val: Value(Scalar(<ZST>))

src/test/mir-opt/const_prop/switch_int/rustc.main.SimplifyBranches-after-const-prop.diff

@@ -7,14 +7,14 @@
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/switch_int.rs:7:11: 7:12
-          _1 = const 1i32;                 // scope 0 at $DIR/switch_int.rs:7:11: 7:12
+          _1 = const 1_i32;                // scope 0 at $DIR/switch_int.rs:7:11: 7:12
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x00000001))
                                            // mir::Constant
                                            // + span: $DIR/switch_int.rs:7:11: 7:12
                                            // + literal: Const { ty: i32, val: Value(Scalar(0x00000001)) }
--         switchInt(const 1i32) -> [1i32: bb2, otherwise: bb1]; // scope 0 at $DIR/switch_int.rs:8:9: 8:10
+-         switchInt(const 1_i32) -> [1_i32: bb2, otherwise: bb1]; // scope 0 at $DIR/switch_int.rs:8:9: 8:10
 -                                          // ty::Const
 -                                          // + ty: i32
 -                                          // + val: Value(Scalar(0x00000001))
@@ -25,7 +25,7 @@
       }
   
       bb1: {
-          _0 = const foo(const -1i32) -> bb3; // scope 0 at $DIR/switch_int.rs:9:14: 9:21
+          _0 = const foo(const -1_i32) -> bb3; // scope 0 at $DIR/switch_int.rs:9:14: 9:21
                                            // ty::Const
                                            // + ty: fn(i32) {foo}
                                            // + val: Value(Scalar(<ZST>))
@@ -41,7 +41,7 @@
       }
   
       bb2: {
-          _0 = const foo(const 0i32) -> bb3; // scope 0 at $DIR/switch_int.rs:8:14: 8:20
+          _0 = const foo(const 0_i32) -> bb3; // scope 0 at $DIR/switch_int.rs:8:14: 8:20
                                            // ty::Const
                                            // + ty: fn(i32) {foo}
                                            // + val: Value(Scalar(<ZST>))

src/test/mir-opt/const_prop/tuple_literal_propagation/rustc.main.ConstProp.diff

@@ -12,7 +12,7 @@
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/tuple_literal_propagation.rs:3:9: 3:10
-          _1 = (const 1u32, const 2u32);   // scope 0 at $DIR/tuple_literal_propagation.rs:3:13: 3:19
+          _1 = (const 1_u32, const 2_u32); // scope 0 at $DIR/tuple_literal_propagation.rs:3:13: 3:19
                                            // ty::Const
                                            // + ty: u32
                                            // + val: Value(Scalar(0x00000001))
@@ -30,7 +30,7 @@
           StorageLive(_2);                 // scope 1 at $DIR/tuple_literal_propagation.rs:5:5: 5:15
           StorageLive(_3);                 // scope 1 at $DIR/tuple_literal_propagation.rs:5:13: 5:14
 -         _3 = _1;                         // scope 1 at $DIR/tuple_literal_propagation.rs:5:13: 5:14
-+         _3 = (const 1u32, const 2u32);   // scope 1 at $DIR/tuple_literal_propagation.rs:5:13: 5:14
++         _3 = (const 1_u32, const 2_u32); // scope 1 at $DIR/tuple_literal_propagation.rs:5:13: 5:14
 +                                          // ty::Const
 +                                          // + ty: u32
 +                                          // + val: Value(Scalar(0x00000001))

src/test/mir-opt/const_prop_miscompile/rustc.bar.ConstProp.diff

@@ -19,8 +19,8 @@
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/const_prop_miscompile.rs:12:9: 12:14
--         _1 = (const 1i32,);              // scope 0 at $DIR/const_prop_miscompile.rs:12:17: 12:21
-+         _1 = const (1i32,);              // scope 0 at $DIR/const_prop_miscompile.rs:12:17: 12:21
+-         _1 = (const 1_i32,);             // scope 0 at $DIR/const_prop_miscompile.rs:12:17: 12:21
++         _1 = const (1_i32,);             // scope 0 at $DIR/const_prop_miscompile.rs:12:17: 12:21
                                            // ty::Const
 -                                          // + ty: i32
 +                                          // + ty: (i32,)
@@ -33,7 +33,7 @@
           StorageLive(_2);                 // scope 1 at $DIR/const_prop_miscompile.rs:13:5: 15:6
           StorageLive(_3);                 // scope 2 at $DIR/const_prop_miscompile.rs:14:10: 14:22
           _3 = &raw mut (_1.0: i32);       // scope 2 at $DIR/const_prop_miscompile.rs:14:10: 14:22
-          (*_3) = const 5i32;              // scope 2 at $DIR/const_prop_miscompile.rs:14:9: 14:26
+          (*_3) = const 5_i32;             // scope 2 at $DIR/const_prop_miscompile.rs:14:9: 14:26
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x00000005))
@@ -52,7 +52,7 @@
           StorageLive(_4);                 // scope 1 at $DIR/const_prop_miscompile.rs:16:9: 16:10
           StorageLive(_5);                 // scope 1 at $DIR/const_prop_miscompile.rs:16:13: 16:20
           _5 = (_1.0: i32);                // scope 1 at $DIR/const_prop_miscompile.rs:16:15: 16:18
-          _4 = Eq(move _5, const 5i32);    // scope 1 at $DIR/const_prop_miscompile.rs:16:13: 16:25
+          _4 = Eq(move _5, const 5_i32);   // scope 1 at $DIR/const_prop_miscompile.rs:16:13: 16:25
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x00000005))

src/test/mir-opt/const_prop_miscompile/rustc.foo.ConstProp.diff

@@ -16,8 +16,8 @@
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/const_prop_miscompile.rs:5:9: 5:14
--         _1 = (const 1i32,);              // scope 0 at $DIR/const_prop_miscompile.rs:5:17: 5:21
-+         _1 = const (1i32,);              // scope 0 at $DIR/const_prop_miscompile.rs:5:17: 5:21
+-         _1 = (const 1_i32,);             // scope 0 at $DIR/const_prop_miscompile.rs:5:17: 5:21
++         _1 = const (1_i32,);             // scope 0 at $DIR/const_prop_miscompile.rs:5:17: 5:21
                                            // ty::Const
 -                                          // + ty: i32
 +                                          // + ty: (i32,)
@@ -29,7 +29,7 @@
 +                                          // + literal: Const { ty: (i32,), val: Value(Scalar(0x00000001)) }
           StorageLive(_2);                 // scope 1 at $DIR/const_prop_miscompile.rs:6:6: 6:14
           _2 = &mut (_1.0: i32);           // scope 1 at $DIR/const_prop_miscompile.rs:6:6: 6:14
-          (*_2) = const 5i32;              // scope 1 at $DIR/const_prop_miscompile.rs:6:5: 6:18
+          (*_2) = const 5_i32;             // scope 1 at $DIR/const_prop_miscompile.rs:6:5: 6:18
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x00000005))
@@ -40,7 +40,7 @@
           StorageLive(_3);                 // scope 1 at $DIR/const_prop_miscompile.rs:7:9: 7:10
           StorageLive(_4);                 // scope 1 at $DIR/const_prop_miscompile.rs:7:13: 7:20
           _4 = (_1.0: i32);                // scope 1 at $DIR/const_prop_miscompile.rs:7:15: 7:18
-          _3 = Eq(move _4, const 5i32);    // scope 1 at $DIR/const_prop_miscompile.rs:7:13: 7:25
+          _3 = Eq(move _4, const 5_i32);   // scope 1 at $DIR/const_prop_miscompile.rs:7:13: 7:25
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x00000005))

src/test/mir-opt/copy_propagation_arg/rustc.arg_src.CopyPropagation.diff

@@ -12,7 +12,7 @@
       bb0: {
           StorageLive(_2);                 // scope 0 at $DIR/copy_propagation_arg.rs:28:9: 28:10
           _2 = _1;                         // scope 0 at $DIR/copy_propagation_arg.rs:28:13: 28:14
-          _1 = const 123i32;               // scope 1 at $DIR/copy_propagation_arg.rs:29:5: 29:12
+          _1 = const 123_i32;              // scope 1 at $DIR/copy_propagation_arg.rs:29:5: 29:12
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x0000007b))

src/test/mir-opt/copy_propagation_arg/rustc.bar.CopyPropagation.diff

@@ -23,7 +23,7 @@
       bb1: {
           StorageDead(_3);                 // scope 0 at $DIR/copy_propagation_arg.rs:16:12: 16:13
           StorageDead(_2);                 // scope 0 at $DIR/copy_propagation_arg.rs:16:13: 16:14
-          _1 = const 5u8;                  // scope 0 at $DIR/copy_propagation_arg.rs:17:5: 17:10
+          _1 = const 5_u8;                 // scope 0 at $DIR/copy_propagation_arg.rs:17:5: 17:10
                                            // ty::Const
                                            // + ty: u8
                                            // + val: Value(Scalar(0x05))

src/test/mir-opt/exponential-or/rustc.match_tuple.SimplifyCfg-initial.after.mir

@@ -19,11 +19,11 @@ fn match_tuple(_1: (u32, bool, std::option::Option<i32>, u32)) -> u32 {
 
     bb0: {
         FakeRead(ForMatchedPlace, _1);   // scope 0 at $DIR/exponential-or.rs:7:11: 7:12
-        switchInt((_1.0: u32)) -> [1u32: bb2, 4u32: bb2, otherwise: bb1]; // scope 0 at $DIR/exponential-or.rs:8:15: 8:16
+        switchInt((_1.0: u32)) -> [1_u32: bb2, 4_u32: bb2, otherwise: bb1]; // scope 0 at $DIR/exponential-or.rs:8:15: 8:16
     }
 
     bb1: {
-        _0 = const 0u32;                 // scope 0 at $DIR/exponential-or.rs:9:14: 9:15
+        _0 = const 0_u32;                // scope 0 at $DIR/exponential-or.rs:9:14: 9:15
                                          // ty::Const
                                          // + ty: u32
                                          // + val: Value(Scalar(0x00000000))
@@ -35,15 +35,15 @@ fn match_tuple(_1: (u32, bool, std::option::Option<i32>, u32)) -> u32 {
 
     bb2: {
         _2 = discriminant((_1.2: std::option::Option<i32>)); // scope 0 at $DIR/exponential-or.rs:8:37: 8:48
-        switchInt(move _2) -> [0isize: bb4, 1isize: bb3, otherwise: bb1]; // scope 0 at $DIR/exponential-or.rs:8:37: 8:48
+        switchInt(move _2) -> [0_isize: bb4, 1_isize: bb3, otherwise: bb1]; // scope 0 at $DIR/exponential-or.rs:8:37: 8:48
     }
 
     bb3: {
-        switchInt((((_1.2: std::option::Option<i32>) as Some).0: i32)) -> [1i32: bb4, 8i32: bb4, otherwise: bb1]; // scope 0 at $DIR/exponential-or.rs:8:42: 8:43
+        switchInt((((_1.2: std::option::Option<i32>) as Some).0: i32)) -> [1_i32: bb4, 8_i32: bb4, otherwise: bb1]; // scope 0 at $DIR/exponential-or.rs:8:42: 8:43
     }
 
     bb4: {
-        _5 = Le(const 6u32, (_1.3: u32)); // scope 0 at $DIR/exponential-or.rs:8:62: 8:67
+        _5 = Le(const 6_u32, (_1.3: u32)); // scope 0 at $DIR/exponential-or.rs:8:62: 8:67
                                          // ty::Const
                                          // + ty: u32
                                          // + val: Value(Scalar(0x00000006))
@@ -54,7 +54,7 @@ fn match_tuple(_1: (u32, bool, std::option::Option<i32>, u32)) -> u32 {
     }
 
     bb5: {
-        _6 = Le((_1.3: u32), const 9u32); // scope 0 at $DIR/exponential-or.rs:8:62: 8:67
+        _6 = Le((_1.3: u32), const 9_u32); // scope 0 at $DIR/exponential-or.rs:8:62: 8:67
                                          // ty::Const
                                          // + ty: u32
                                          // + val: Value(Scalar(0x00000009))
@@ -65,7 +65,7 @@ fn match_tuple(_1: (u32, bool, std::option::Option<i32>, u32)) -> u32 {
     }
 
     bb6: {
-        _3 = Le(const 13u32, (_1.3: u32)); // scope 0 at $DIR/exponential-or.rs:8:70: 8:77
+        _3 = Le(const 13_u32, (_1.3: u32)); // scope 0 at $DIR/exponential-or.rs:8:70: 8:77
                                          // ty::Const
                                          // + ty: u32
                                          // + val: Value(Scalar(0x0000000d))
@@ -76,7 +76,7 @@ fn match_tuple(_1: (u32, bool, std::option::Option<i32>, u32)) -> u32 {
     }
 
     bb7: {
-        _4 = Le((_1.3: u32), const 16u32); // scope 0 at $DIR/exponential-or.rs:8:70: 8:77
+        _4 = Le((_1.3: u32), const 16_u32); // scope 0 at $DIR/exponential-or.rs:8:70: 8:77
                                          // ty::Const
                                          // + ty: u32
                                          // + val: Value(Scalar(0x00000010))

src/test/mir-opt/generator-drop-cleanup/rustc.main-{{closure}}.generator_drop.0.mir

@@ -34,7 +34,7 @@ fn main::{{closure}}#0(_1: *mut [generator@$DIR/generator-drop-cleanup.rs:10:15:
 
     bb0: {
         _9 = discriminant((*_1));        // scope 0 at $DIR/generator-drop-cleanup.rs:10:15: 13:6
-        switchInt(move _9) -> [0u32: bb7, 3u32: bb11, otherwise: bb12]; // scope 0 at $DIR/generator-drop-cleanup.rs:10:15: 13:6
+        switchInt(move _9) -> [0_u32: bb7, 3_u32: bb11, otherwise: bb12]; // scope 0 at $DIR/generator-drop-cleanup.rs:10:15: 13:6
     }
 
     bb1 (cleanup): {

src/test/mir-opt/generator-storage-dead-unwind/rustc.main-{{closure}}.StateTransform.before.mir

@@ -21,7 +21,7 @@ yields ()
 
     bb0: {
         StorageLive(_3);                 // scope 0 at $DIR/generator-storage-dead-unwind.rs:23:13: 23:14
-        _3 = Foo(const 5i32);            // scope 0 at $DIR/generator-storage-dead-unwind.rs:23:17: 23:23
+        _3 = Foo(const 5_i32);           // scope 0 at $DIR/generator-storage-dead-unwind.rs:23:17: 23:23
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000005))
@@ -29,7 +29,7 @@ yields ()
                                          // + span: $DIR/generator-storage-dead-unwind.rs:23:21: 23:22
                                          // + literal: Const { ty: i32, val: Value(Scalar(0x00000005)) }
         StorageLive(_4);                 // scope 1 at $DIR/generator-storage-dead-unwind.rs:24:13: 24:14
-        _4 = Bar(const 6i32);            // scope 1 at $DIR/generator-storage-dead-unwind.rs:24:17: 24:23
+        _4 = Bar(const 6_i32);           // scope 1 at $DIR/generator-storage-dead-unwind.rs:24:17: 24:23
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000006))

src/test/mir-opt/generator-tiny/rustc.main-{{closure}}.generator_resume.0.mir

@@ -32,7 +32,7 @@ fn main::{{closure}}#0(_1: std::pin::Pin<&mut [generator@$DIR/generator-tiny.rs:
 
     bb0: {
         _11 = discriminant((*(_1.0: &mut [generator@$DIR/generator-tiny.rs:19:16: 25:6 {u8, HasDrop, ()}]))); // scope 0 at $DIR/generator-tiny.rs:19:16: 25:6
-        switchInt(move _11) -> [0u32: bb1, 3u32: bb5, otherwise: bb6]; // scope 0 at $DIR/generator-tiny.rs:19:16: 25:6
+        switchInt(move _11) -> [0_u32: bb1, 3_u32: bb5, otherwise: bb6]; // scope 0 at $DIR/generator-tiny.rs:19:16: 25:6
     }
 
     bb1: {

src/test/mir-opt/inline/inline-any-operand/rustc.bar.Inline.after.mir

@@ -25,14 +25,14 @@ fn bar() -> bool {
                                          // + literal: Const { ty: fn(i32, i32) -> bool {foo}, val: Value(Scalar(<ZST>)) }
         StorageLive(_2);                 // scope 1 at $DIR/inline-any-operand.rs:12:5: 12:6
         _2 = _1;                         // scope 1 at $DIR/inline-any-operand.rs:12:5: 12:6
-        _3 = const 1i32;                 // scope 1 at $DIR/inline-any-operand.rs:12:5: 12:13
+        _3 = const 1_i32;                // scope 1 at $DIR/inline-any-operand.rs:12:5: 12:13
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000001))
                                          // mir::Constant
                                          // + span: $DIR/inline-any-operand.rs:12:7: 12:8
                                          // + literal: Const { ty: i32, val: Value(Scalar(0x00000001)) }
-        _4 = const -1i32;                // scope 1 at $DIR/inline-any-operand.rs:12:5: 12:13
+        _4 = const -1_i32;               // scope 1 at $DIR/inline-any-operand.rs:12:5: 12:13
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0xffffffff))

src/test/mir-opt/inline/inline-into-box-place/32bit/rustc.main.Inline.diff

@@ -19,7 +19,7 @@
           _2 = Box(std::vec::Vec<u32>);    // scope 0 at $DIR/inline-into-box-place.rs:8:29: 8:43
 -         (*_2) = const std::vec::Vec::<u32>::new() -> [return: bb2, unwind: bb4]; // scope 0 at $DIR/inline-into-box-place.rs:8:33: 8:43
 +         _4 = &mut (*_2);                 // scope 0 at $DIR/inline-into-box-place.rs:8:33: 8:43
-+         ((*_4).0: alloc::raw_vec::RawVec<u32>) = const alloc::raw_vec::RawVec::<u32> { ptr: std::ptr::Unique::<u32> { pointer: {0x4 as *const u32}, _marker: std::marker::PhantomData::<u32> }, cap: 0usize, alloc: std::alloc::Global }; // scope 2 at $SRC_DIR/liballoc/vec.rs:LL:COL
++         ((*_4).0: alloc::raw_vec::RawVec<u32>) = const alloc::raw_vec::RawVec::<u32> { ptr: std::ptr::Unique::<u32> { pointer: {0x4 as *const u32}, _marker: std::marker::PhantomData::<u32> }, cap: 0_usize, alloc: std::alloc::Global }; // scope 2 at $SRC_DIR/liballoc/vec.rs:LL:COL
                                            // ty::Const
 -                                          // + ty: fn() -> std::vec::Vec<u32> {std::vec::Vec::<u32>::new}
 -                                          // + val: Value(Scalar(<ZST>))
@@ -39,7 +39,7 @@
 +                                          // + span: $SRC_DIR/liballoc/vec.rs:LL:COL
 +                                          // + user_ty: UserType(0)
 +                                          // + literal: Const { ty: alloc::raw_vec::RawVec<u32>, val: Value(ByRef { alloc: Allocation { bytes: [4, 0, 0, 0, 0, 0, 0, 0], relocations: Relocations(SortedMap { data: [] }), init_mask: InitMask { blocks: [255], len: Size { raw: 8 } }, size: Size { raw: 8 }, align: Align { pow2: 2 }, mutability: Not, extra: () }, offset: Size { raw: 0 } }) }
-+         ((*_4).1: usize) = const 0usize; // scope 2 at $SRC_DIR/liballoc/vec.rs:LL:COL
++         ((*_4).1: usize) = const 0_usize; // scope 2 at $SRC_DIR/liballoc/vec.rs:LL:COL
 +                                          // ty::Const
 +                                          // + ty: usize
 +                                          // + val: Value(Scalar(0x00000000))

src/test/mir-opt/inline/inline-into-box-place/64bit/rustc.main.Inline.diff

@@ -19,7 +19,7 @@
           _2 = Box(std::vec::Vec<u32>);    // scope 0 at $DIR/inline-into-box-place.rs:8:29: 8:43
 -         (*_2) = const std::vec::Vec::<u32>::new() -> [return: bb2, unwind: bb4]; // scope 0 at $DIR/inline-into-box-place.rs:8:33: 8:43
 +         _4 = &mut (*_2);                 // scope 0 at $DIR/inline-into-box-place.rs:8:33: 8:43
-+         ((*_4).0: alloc::raw_vec::RawVec<u32>) = const alloc::raw_vec::RawVec::<u32> { ptr: std::ptr::Unique::<u32> { pointer: {0x4 as *const u32}, _marker: std::marker::PhantomData::<u32> }, cap: 0usize, alloc: std::alloc::Global }; // scope 2 at $SRC_DIR/liballoc/vec.rs:LL:COL
++         ((*_4).0: alloc::raw_vec::RawVec<u32>) = const alloc::raw_vec::RawVec::<u32> { ptr: std::ptr::Unique::<u32> { pointer: {0x4 as *const u32}, _marker: std::marker::PhantomData::<u32> }, cap: 0_usize, alloc: std::alloc::Global }; // scope 2 at $SRC_DIR/liballoc/vec.rs:LL:COL
                                            // ty::Const
 -                                          // + ty: fn() -> std::vec::Vec<u32> {std::vec::Vec::<u32>::new}
 -                                          // + val: Value(Scalar(<ZST>))
@@ -39,7 +39,7 @@
 +                                          // + span: $SRC_DIR/liballoc/vec.rs:LL:COL
 +                                          // + user_ty: UserType(0)
 +                                          // + literal: Const { ty: alloc::raw_vec::RawVec<u32>, val: Value(ByRef { alloc: Allocation { bytes: [4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], relocations: Relocations(SortedMap { data: [] }), init_mask: InitMask { blocks: [65535], len: Size { raw: 16 } }, size: Size { raw: 16 }, align: Align { pow2: 3 }, mutability: Not, extra: () }, offset: Size { raw: 0 } }) }
-+         ((*_4).1: usize) = const 0usize; // scope 2 at $SRC_DIR/liballoc/vec.rs:LL:COL
++         ((*_4).1: usize) = const 0_usize; // scope 2 at $SRC_DIR/liballoc/vec.rs:LL:COL
 +                                          // ty::Const
 +                                          // + ty: usize
 +                                          // + val: Value(Scalar(0x0000000000000000))

src/test/mir-opt/inline/inline-specialization/rustc.main.Inline.diff

@@ -13,7 +13,7 @@
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/inline-specialization.rs:5:9: 5:10
 -         _1 = const <std::vec::Vec<()> as Foo>::bar() -> bb1; // scope 0 at $DIR/inline-specialization.rs:5:13: 5:38
-+         _1 = const 123u32;               // scope 2 at $DIR/inline-specialization.rs:14:31: 14:34
++         _1 = const 123_u32;              // scope 2 at $DIR/inline-specialization.rs:14:31: 14:34
                                            // ty::Const
 -                                          // + ty: fn() -> u32 {<std::vec::Vec<()> as Foo>::bar}
 -                                          // + val: Value(Scalar(<ZST>))

src/test/mir-opt/instrument_coverage/rustc.bar.InstrumentCoverage.diff

@@ -7,7 +7,7 @@
   
       bb0: {
 +         StorageLive(_1);                 // scope 0 at $DIR/instrument_coverage.rs:18:1: 20:2
-+         _1 = const std::intrinsics::count_code_region(const 0u32) -> bb2; // scope 0 at $DIR/instrument_coverage.rs:18:1: 20:2
++         _1 = const std::intrinsics::count_code_region(const 0_u32) -> bb2; // scope 0 at $DIR/instrument_coverage.rs:18:1: 20:2
 +                                          // ty::Const
 +                                          // + ty: unsafe extern "rust-intrinsic" fn(u32) {std::intrinsics::count_code_region}
 +                                          // + val: Value(Scalar(<ZST>))

src/test/mir-opt/instrument_coverage/rustc.main.InstrumentCoverage.diff

@@ -11,7 +11,7 @@
       bb0: {
 -         falseUnwind -> [real: bb1, cleanup: bb2]; // scope 0 at $DIR/instrument_coverage.rs:10:5: 14:6
 +         StorageLive(_4);                 // scope 0 at $DIR/instrument_coverage.rs:9:1: 15:2
-+         _4 = const std::intrinsics::count_code_region(const 0u32) -> bb7; // scope 0 at $DIR/instrument_coverage.rs:9:1: 15:2
++         _4 = const std::intrinsics::count_code_region(const 0_u32) -> bb7; // scope 0 at $DIR/instrument_coverage.rs:9:1: 15:2
 +                                          // ty::Const
 +                                          // + ty: unsafe extern "rust-intrinsic" fn(u32) {std::intrinsics::count_code_region}
 +                                          // + val: Value(Scalar(<ZST>))

src/test/mir-opt/issue-41697/32bit/rustc.{{impl}}-{{constant}}.SimplifyCfg-qualify-consts.after.mir

@@ -5,7 +5,20 @@
     let mut _1: (usize, bool);           // in scope 0 at $DIR/issue-41697.rs:18:19: 18:22
 
     bb0: {
-        _1 = CheckedAdd(const 1usize, const 1usize); // scope 0 at $DIR/issue-41697.rs:18:19: 18:22
+        _1 = CheckedAdd(const 1_usize, const 1_usize); // scope 0 at $DIR/issue-41697.rs:18:19: 18:22
+                                         // ty::Const
+                                         // + ty: usize
+                                         // + val: Value(Scalar(0x00000001))
+                                         // mir::Constant
+                                         // + span: $DIR/issue-41697.rs:18:19: 18:20
+                                         // + literal: Const { ty: usize, val: Value(Scalar(0x00000001)) }
+                                         // ty::Const
+                                         // + ty: usize
+                                         // + val: Value(Scalar(0x00000001))
+                                         // mir::Constant
+                                         // + span: $DIR/issue-41697.rs:18:21: 18:22
+                                         // + literal: Const { ty: usize, val: Value(Scalar(0x00000001)) }
+        assert(!move (_1.1: bool), "attempt to compute `{} + {}` which would overflow", const 1_usize, const 1_usize) -> [success: bb2, unwind: bb1]; // scope 0 at $DIR/issue-41697.rs:18:19: 18:22
                                          // ty::Const
                                          // + ty: usize
                                          // + val: Value(Scalar(0x00000001))
@@ -18,7 +31,6 @@
                                          // mir::Constant
                                          // + span: $DIR/issue-41697.rs:18:21: 18:22
                                          // + literal: Const { ty: usize, val: Value(Scalar(0x00000001)) }
-        assert(!move (_1.1: bool), "attempt to add with overflow") -> [success: bb2, unwind: bb1]; // scope 0 at $DIR/issue-41697.rs:18:19: 18:22
     }
 
     bb1 (cleanup): {

src/test/mir-opt/issue-41697/64bit/rustc.{{impl}}-{{constant}}.SimplifyCfg-qualify-consts.after.mir

@@ -5,7 +5,20 @@
     let mut _1: (usize, bool);           // in scope 0 at $DIR/issue-41697.rs:18:19: 18:22
 
     bb0: {
-        _1 = CheckedAdd(const 1usize, const 1usize); // scope 0 at $DIR/issue-41697.rs:18:19: 18:22
+        _1 = CheckedAdd(const 1_usize, const 1_usize); // scope 0 at $DIR/issue-41697.rs:18:19: 18:22
+                                         // ty::Const
+                                         // + ty: usize
+                                         // + val: Value(Scalar(0x0000000000000001))
+                                         // mir::Constant
+                                         // + span: $DIR/issue-41697.rs:18:19: 18:20
+                                         // + literal: Const { ty: usize, val: Value(Scalar(0x0000000000000001)) }
+                                         // ty::Const
+                                         // + ty: usize
+                                         // + val: Value(Scalar(0x0000000000000001))
+                                         // mir::Constant
+                                         // + span: $DIR/issue-41697.rs:18:21: 18:22
+                                         // + literal: Const { ty: usize, val: Value(Scalar(0x0000000000000001)) }
+        assert(!move (_1.1: bool), "attempt to compute `{} + {}` which would overflow", const 1_usize, const 1_usize) -> [success: bb2, unwind: bb1]; // scope 0 at $DIR/issue-41697.rs:18:19: 18:22
                                          // ty::Const
                                          // + ty: usize
                                          // + val: Value(Scalar(0x0000000000000001))
@@ -18,7 +31,6 @@
                                          // mir::Constant
                                          // + span: $DIR/issue-41697.rs:18:21: 18:22
                                          // + literal: Const { ty: usize, val: Value(Scalar(0x0000000000000001)) }
-        assert(!move (_1.1: bool), "attempt to add with overflow") -> [success: bb2, unwind: bb1]; // scope 0 at $DIR/issue-41697.rs:18:19: 18:22
     }
 
     bb1 (cleanup): {

src/test/mir-opt/issue-41888/rustc.main.ElaborateDrops.after.mir

@@ -96,7 +96,7 @@ fn main() -> () {
     bb8: {
         StorageDead(_3);                 // scope 1 at $DIR/issue-41888.rs:9:19: 9:20
         _5 = discriminant(_1);           // scope 1 at $DIR/issue-41888.rs:10:16: 10:24
-        switchInt(move _5) -> [0isize: bb10, otherwise: bb9]; // scope 1 at $DIR/issue-41888.rs:10:16: 10:24
+        switchInt(move _5) -> [0_isize: bb10, otherwise: bb9]; // scope 1 at $DIR/issue-41888.rs:10:16: 10:24
     }
 
     bb9: {
@@ -250,7 +250,7 @@ fn main() -> () {
 
     bb20: {
         _10 = discriminant(_1);          // scope 0 at $DIR/issue-41888.rs:15:1: 15:2
-        switchInt(move _10) -> [0isize: bb15, otherwise: bb18]; // scope 0 at $DIR/issue-41888.rs:15:1: 15:2
+        switchInt(move _10) -> [0_isize: bb15, otherwise: bb18]; // scope 0 at $DIR/issue-41888.rs:15:1: 15:2
     }
 
     bb21: {
@@ -259,7 +259,7 @@ fn main() -> () {
 
     bb22 (cleanup): {
         _11 = discriminant(_1);          // scope 0 at $DIR/issue-41888.rs:15:1: 15:2
-        switchInt(move _11) -> [0isize: bb17, otherwise: bb19]; // scope 0 at $DIR/issue-41888.rs:15:1: 15:2
+        switchInt(move _11) -> [0_isize: bb17, otherwise: bb19]; // scope 0 at $DIR/issue-41888.rs:15:1: 15:2
     }
 
     bb23 (cleanup): {

src/test/mir-opt/issue-49232/rustc.main.mir_map.0.mir

@@ -58,7 +58,7 @@ fn main() -> () {
     }
 
     bb7: {
-        _2 = const 4i32;                 // scope 0 at $DIR/issue-49232.rs:9:26: 9:27
+        _2 = const 4_i32;                // scope 0 at $DIR/issue-49232.rs:9:26: 9:27
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000004))

src/test/mir-opt/issue-62289/rustc.test.ElaborateDrops.before.mir

@@ -46,7 +46,7 @@ fn test() -> std::option::Option<std::boxed::Box<u32>> {
     bb2: {
         StorageDead(_4);                 // scope 0 at $DIR/issue-62289.rs:9:19: 9:20
         _5 = discriminant(_3);           // scope 0 at $DIR/issue-62289.rs:9:19: 9:20
-        switchInt(move _5) -> [0isize: bb4, 1isize: bb6, otherwise: bb5]; // scope 0 at $DIR/issue-62289.rs:9:19: 9:20
+        switchInt(move _5) -> [0_isize: bb4, 1_isize: bb6, otherwise: bb5]; // scope 0 at $DIR/issue-62289.rs:9:19: 9:20
     }
 
     bb3 (cleanup): {

src/test/mir-opt/issue-72181/32bit/rustc.foo.mir_map.0.mir

@@ -9,7 +9,7 @@ fn foo(_1: [(Never, u32); 1]) -> u32 {
 
     bb0: {
         StorageLive(_2);                 // scope 0 at $DIR/issue-72181.rs:16:43: 16:44
-        _2 = const 0usize;               // scope 0 at $DIR/issue-72181.rs:16:43: 16:44
+        _2 = const 0_usize;              // scope 0 at $DIR/issue-72181.rs:16:43: 16:44
                                          // ty::Const
                                          // + ty: usize
                                          // + val: Value(Scalar(0x00000000))

src/test/mir-opt/issue-72181/32bit/rustc.main.mir_map.0.mir

@@ -39,7 +39,7 @@ fn main() -> () {
         StorageDead(_1);                 // scope 0 at $DIR/issue-72181.rs:24:34: 24:35
         StorageLive(_2);                 // scope 1 at $DIR/issue-72181.rs:26:9: 26:10
         StorageLive(_3);                 // scope 1 at $DIR/issue-72181.rs:26:14: 26:27
-        _3 = Foo { a: const 42u64 };     // scope 1 at $DIR/issue-72181.rs:26:14: 26:27
+        _3 = Foo { a: const 42_u64 };    // scope 1 at $DIR/issue-72181.rs:26:14: 26:27
                                          // ty::Const
                                          // + ty: u64
                                          // + val: Value(Scalar(0x000000000000002a))
@@ -47,7 +47,7 @@ fn main() -> () {
                                          // + span: $DIR/issue-72181.rs:26:23: 26:25
                                          // + literal: Const { ty: u64, val: Value(Scalar(0x000000000000002a)) }
         StorageLive(_4);                 // scope 1 at $DIR/issue-72181.rs:26:29: 26:42
-        _4 = Foo { a: const 10u64 };     // scope 1 at $DIR/issue-72181.rs:26:29: 26:42
+        _4 = Foo { a: const 10_u64 };    // scope 1 at $DIR/issue-72181.rs:26:29: 26:42
                                          // ty::Const
                                          // + ty: u64
                                          // + val: Value(Scalar(0x000000000000000a))
@@ -60,7 +60,7 @@ fn main() -> () {
         FakeRead(ForLet, _2);            // scope 1 at $DIR/issue-72181.rs:26:9: 26:10
         StorageLive(_5);                 // scope 2 at $DIR/issue-72181.rs:27:13: 27:30
         StorageLive(_6);                 // scope 4 at $DIR/issue-72181.rs:27:24: 27:25
-        _6 = const 0usize;               // scope 4 at $DIR/issue-72181.rs:27:24: 27:25
+        _6 = const 0_usize;              // scope 4 at $DIR/issue-72181.rs:27:24: 27:25
                                          // ty::Const
                                          // + ty: usize
                                          // + val: Value(Scalar(0x00000000))

src/test/mir-opt/issue-72181/64bit/rustc.foo.mir_map.0.mir

@@ -9,7 +9,7 @@ fn foo(_1: [(Never, u32); 1]) -> u32 {
 
     bb0: {
         StorageLive(_2);                 // scope 0 at $DIR/issue-72181.rs:16:43: 16:44
-        _2 = const 0usize;               // scope 0 at $DIR/issue-72181.rs:16:43: 16:44
+        _2 = const 0_usize;              // scope 0 at $DIR/issue-72181.rs:16:43: 16:44
                                          // ty::Const
                                          // + ty: usize
                                          // + val: Value(Scalar(0x0000000000000000))

src/test/mir-opt/issue-72181/64bit/rustc.main.mir_map.0.mir

@@ -39,7 +39,7 @@ fn main() -> () {
         StorageDead(_1);                 // scope 0 at $DIR/issue-72181.rs:24:34: 24:35
         StorageLive(_2);                 // scope 1 at $DIR/issue-72181.rs:26:9: 26:10
         StorageLive(_3);                 // scope 1 at $DIR/issue-72181.rs:26:14: 26:27
-        _3 = Foo { a: const 42u64 };     // scope 1 at $DIR/issue-72181.rs:26:14: 26:27
+        _3 = Foo { a: const 42_u64 };    // scope 1 at $DIR/issue-72181.rs:26:14: 26:27
                                          // ty::Const
                                          // + ty: u64
                                          // + val: Value(Scalar(0x000000000000002a))
@@ -47,7 +47,7 @@ fn main() -> () {
                                          // + span: $DIR/issue-72181.rs:26:23: 26:25
                                          // + literal: Const { ty: u64, val: Value(Scalar(0x000000000000002a)) }
         StorageLive(_4);                 // scope 1 at $DIR/issue-72181.rs:26:29: 26:42
-        _4 = Foo { a: const 10u64 };     // scope 1 at $DIR/issue-72181.rs:26:29: 26:42
+        _4 = Foo { a: const 10_u64 };    // scope 1 at $DIR/issue-72181.rs:26:29: 26:42
                                          // ty::Const
                                          // + ty: u64
                                          // + val: Value(Scalar(0x000000000000000a))
@@ -60,7 +60,7 @@ fn main() -> () {
         FakeRead(ForLet, _2);            // scope 1 at $DIR/issue-72181.rs:26:9: 26:10
         StorageLive(_5);                 // scope 2 at $DIR/issue-72181.rs:27:13: 27:30
         StorageLive(_6);                 // scope 4 at $DIR/issue-72181.rs:27:24: 27:25
-        _6 = const 0usize;               // scope 4 at $DIR/issue-72181.rs:27:24: 27:25
+        _6 = const 0_usize;              // scope 4 at $DIR/issue-72181.rs:27:24: 27:25
                                          // ty::Const
                                          // + ty: usize
                                          // + val: Value(Scalar(0x0000000000000000))

src/test/mir-opt/loop_test/rustc.main.SimplifyCfg-qualify-consts.after.mir

@@ -67,7 +67,7 @@ fn main() -> () {
 
     bb6: {
         StorageLive(_6);                 // scope 0 at $DIR/loop_test.rs:14:13: 14:14
-        _6 = const 1i32;                 // scope 0 at $DIR/loop_test.rs:14:17: 14:18
+        _6 = const 1_i32;                // scope 0 at $DIR/loop_test.rs:14:17: 14:18
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000001))

src/test/mir-opt/match-arm-scopes/rustc.complicated_match.ElaborateDrops.after.mir

@@ -54,7 +54,7 @@ fn complicated_match(_1: bool, _2: (bool, bool, std::string::String)) -> i32 {
     }
 
     bb5: {
-        _0 = const 1i32;                 // scope 1 at $DIR/match-arm-scopes.rs:16:77: 16:78
+        _0 = const 1_i32;                // scope 1 at $DIR/match-arm-scopes.rs:16:77: 16:78
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000001))
@@ -82,7 +82,7 @@ fn complicated_match(_1: bool, _2: (bool, bool, std::string::String)) -> i32 {
     }
 
     bb8: {
-        _0 = const 3i32;                 // scope 0 at $DIR/match-arm-scopes.rs:16:59: 16:60
+        _0 = const 3_i32;                // scope 0 at $DIR/match-arm-scopes.rs:16:59: 16:60
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000003))
@@ -142,7 +142,7 @@ fn complicated_match(_1: bool, _2: (bool, bool, std::string::String)) -> i32 {
     }
 
     bb16: {
-        _0 = const 3i32;                 // scope 0 at $DIR/match-arm-scopes.rs:16:59: 16:60
+        _0 = const 3_i32;                // scope 0 at $DIR/match-arm-scopes.rs:16:59: 16:60
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000003))
@@ -181,7 +181,7 @@ fn complicated_match(_1: bool, _2: (bool, bool, std::string::String)) -> i32 {
     }
 
     bb20: {
-        _0 = const 2i32;                 // scope 2 at $DIR/match-arm-scopes.rs:17:41: 17:42
+        _0 = const 2_i32;                // scope 2 at $DIR/match-arm-scopes.rs:17:41: 17:42
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000002))

src/test/mir-opt/match-arm-scopes/rustc.complicated_match.SimplifyCfg-initial.after.mir

@@ -67,7 +67,7 @@ fn complicated_match(_1: bool, _2: (bool, bool, std::string::String)) -> i32 {
     }
 
     bb8: {
-        _0 = const 1i32;                 // scope 1 at $DIR/match-arm-scopes.rs:16:77: 16:78
+        _0 = const 1_i32;                // scope 1 at $DIR/match-arm-scopes.rs:16:77: 16:78
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000001))
@@ -102,7 +102,7 @@ fn complicated_match(_1: bool, _2: (bool, bool, std::string::String)) -> i32 {
     }
 
     bb12: {
-        _0 = const 3i32;                 // scope 0 at $DIR/match-arm-scopes.rs:16:59: 16:60
+        _0 = const 3_i32;                // scope 0 at $DIR/match-arm-scopes.rs:16:59: 16:60
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000003))
@@ -173,7 +173,7 @@ fn complicated_match(_1: bool, _2: (bool, bool, std::string::String)) -> i32 {
     }
 
     bb21: {
-        _0 = const 3i32;                 // scope 0 at $DIR/match-arm-scopes.rs:16:59: 16:60
+        _0 = const 3_i32;                // scope 0 at $DIR/match-arm-scopes.rs:16:59: 16:60
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000003))
@@ -216,7 +216,7 @@ fn complicated_match(_1: bool, _2: (bool, bool, std::string::String)) -> i32 {
     }
 
     bb25: {
-        _0 = const 2i32;                 // scope 2 at $DIR/match-arm-scopes.rs:17:41: 17:42
+        _0 = const 2_i32;                // scope 2 at $DIR/match-arm-scopes.rs:17:41: 17:42
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000002))

src/test/mir-opt/match_false_edges/rustc.full_tested_match.PromoteTemps.after.mir

@@ -26,7 +26,7 @@ fn full_tested_match() -> () {
     bb0: {
         StorageLive(_1);                 // scope 0 at $DIR/match_false_edges.rs:15:13: 19:6
         StorageLive(_2);                 // scope 0 at $DIR/match_false_edges.rs:15:19: 15:27
-        _2 = std::option::Option::<i32>::Some(const 42i32); // scope 0 at $DIR/match_false_edges.rs:15:19: 15:27
+        _2 = std::option::Option::<i32>::Some(const 42_i32); // scope 0 at $DIR/match_false_edges.rs:15:19: 15:27
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x0000002a))
@@ -35,7 +35,7 @@ fn full_tested_match() -> () {
                                          // + literal: Const { ty: i32, val: Value(Scalar(0x0000002a)) }
         FakeRead(ForMatchedPlace, _2);   // scope 0 at $DIR/match_false_edges.rs:15:19: 15:27
         _3 = discriminant(_2);           // scope 0 at $DIR/match_false_edges.rs:16:9: 16:16
-        switchInt(move _3) -> [0isize: bb2, 1isize: bb3, otherwise: bb5]; // scope 0 at $DIR/match_false_edges.rs:16:9: 16:16
+        switchInt(move _3) -> [0_isize: bb2, 1_isize: bb3, otherwise: bb5]; // scope 0 at $DIR/match_false_edges.rs:16:9: 16:16
     }
 
     bb1 (cleanup): {
@@ -43,7 +43,7 @@ fn full_tested_match() -> () {
     }
 
     bb2: {
-        _1 = (const 3i32, const 3i32);   // scope 0 at $DIR/match_false_edges.rs:18:17: 18:23
+        _1 = (const 3_i32, const 3_i32); // scope 0 at $DIR/match_false_edges.rs:18:17: 18:23
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000003))
@@ -104,7 +104,7 @@ fn full_tested_match() -> () {
         _5 = ((_2 as Some).0: i32);      // scope 0 at $DIR/match_false_edges.rs:16:14: 16:15
         StorageLive(_8);                 // scope 2 at $DIR/match_false_edges.rs:16:35: 16:36
         _8 = _5;                         // scope 2 at $DIR/match_false_edges.rs:16:35: 16:36
-        _1 = (const 1i32, move _8);      // scope 2 at $DIR/match_false_edges.rs:16:31: 16:37
+        _1 = (const 1_i32, move _8);     // scope 2 at $DIR/match_false_edges.rs:16:31: 16:37
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000001))
@@ -128,7 +128,7 @@ fn full_tested_match() -> () {
         _9 = ((_2 as Some).0: i32);      // scope 0 at $DIR/match_false_edges.rs:17:14: 17:15
         StorageLive(_10);                // scope 3 at $DIR/match_false_edges.rs:17:24: 17:25
         _10 = _9;                        // scope 3 at $DIR/match_false_edges.rs:17:24: 17:25
-        _1 = (const 2i32, move _10);     // scope 3 at $DIR/match_false_edges.rs:17:20: 17:26
+        _1 = (const 2_i32, move _10);    // scope 3 at $DIR/match_false_edges.rs:17:20: 17:26
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000002))

src/test/mir-opt/match_false_edges/rustc.full_tested_match2.PromoteTemps.before.mir

@@ -25,7 +25,7 @@ fn full_tested_match2() -> () {
     bb0: {
         StorageLive(_1);                 // scope 0 at $DIR/match_false_edges.rs:26:13: 30:6
         StorageLive(_2);                 // scope 0 at $DIR/match_false_edges.rs:26:19: 26:27
-        _2 = std::option::Option::<i32>::Some(const 42i32); // scope 0 at $DIR/match_false_edges.rs:26:19: 26:27
+        _2 = std::option::Option::<i32>::Some(const 42_i32); // scope 0 at $DIR/match_false_edges.rs:26:19: 26:27
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x0000002a))
@@ -34,7 +34,7 @@ fn full_tested_match2() -> () {
                                          // + literal: Const { ty: i32, val: Value(Scalar(0x0000002a)) }
         FakeRead(ForMatchedPlace, _2);   // scope 0 at $DIR/match_false_edges.rs:26:19: 26:27
         _3 = discriminant(_2);           // scope 0 at $DIR/match_false_edges.rs:27:9: 27:16
-        switchInt(move _3) -> [0isize: bb2, 1isize: bb3, otherwise: bb5]; // scope 0 at $DIR/match_false_edges.rs:27:9: 27:16
+        switchInt(move _3) -> [0_isize: bb2, 1_isize: bb3, otherwise: bb5]; // scope 0 at $DIR/match_false_edges.rs:27:9: 27:16
     }
 
     bb1 (cleanup): {
@@ -54,7 +54,7 @@ fn full_tested_match2() -> () {
         _9 = ((_2 as Some).0: i32);      // scope 0 at $DIR/match_false_edges.rs:29:14: 29:15
         StorageLive(_10);                // scope 3 at $DIR/match_false_edges.rs:29:24: 29:25
         _10 = _9;                        // scope 3 at $DIR/match_false_edges.rs:29:24: 29:25
-        _1 = (const 2i32, move _10);     // scope 3 at $DIR/match_false_edges.rs:29:20: 29:26
+        _1 = (const 2_i32, move _10);    // scope 3 at $DIR/match_false_edges.rs:29:20: 29:26
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000002))
@@ -96,7 +96,7 @@ fn full_tested_match2() -> () {
         _5 = ((_2 as Some).0: i32);      // scope 0 at $DIR/match_false_edges.rs:27:14: 27:15
         StorageLive(_8);                 // scope 2 at $DIR/match_false_edges.rs:27:35: 27:36
         _8 = _5;                         // scope 2 at $DIR/match_false_edges.rs:27:35: 27:36
-        _1 = (const 1i32, move _8);      // scope 2 at $DIR/match_false_edges.rs:27:31: 27:37
+        _1 = (const 1_i32, move _8);     // scope 2 at $DIR/match_false_edges.rs:27:31: 27:37
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000001))
@@ -116,7 +116,7 @@ fn full_tested_match2() -> () {
     }
 
     bb10: {
-        _1 = (const 3i32, const 3i32);   // scope 0 at $DIR/match_false_edges.rs:28:17: 28:23
+        _1 = (const 3_i32, const 3_i32); // scope 0 at $DIR/match_false_edges.rs:28:17: 28:23
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000003))

src/test/mir-opt/match_false_edges/rustc.main.PromoteTemps.before.mir

@@ -36,7 +36,7 @@ fn main() -> () {
     bb0: {
         StorageLive(_1);                 // scope 0 at $DIR/match_false_edges.rs:35:13: 40:6
         StorageLive(_2);                 // scope 0 at $DIR/match_false_edges.rs:35:19: 35:26
-        _2 = std::option::Option::<i32>::Some(const 1i32); // scope 0 at $DIR/match_false_edges.rs:35:19: 35:26
+        _2 = std::option::Option::<i32>::Some(const 1_i32); // scope 0 at $DIR/match_false_edges.rs:35:19: 35:26
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000001))
@@ -45,7 +45,7 @@ fn main() -> () {
                                          // + literal: Const { ty: i32, val: Value(Scalar(0x00000001)) }
         FakeRead(ForMatchedPlace, _2);   // scope 0 at $DIR/match_false_edges.rs:35:19: 35:26
         _4 = discriminant(_2);           // scope 0 at $DIR/match_false_edges.rs:36:9: 36:17
-        switchInt(move _4) -> [1isize: bb3, otherwise: bb2]; // scope 0 at $DIR/match_false_edges.rs:36:9: 36:17
+        switchInt(move _4) -> [1_isize: bb3, otherwise: bb2]; // scope 0 at $DIR/match_false_edges.rs:36:9: 36:17
     }
 
     bb1 (cleanup): {
@@ -63,7 +63,7 @@ fn main() -> () {
     bb4: {
         StorageLive(_14);                // scope 0 at $DIR/match_false_edges.rs:39:9: 39:11
         _14 = _2;                        // scope 0 at $DIR/match_false_edges.rs:39:9: 39:11
-        _1 = const 4i32;                 // scope 5 at $DIR/match_false_edges.rs:39:15: 39:16
+        _1 = const 4_i32;                // scope 5 at $DIR/match_false_edges.rs:39:15: 39:16
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000004))
@@ -102,7 +102,7 @@ fn main() -> () {
         FakeRead(ForGuardBinding, _7);   // scope 0 at $DIR/match_false_edges.rs:36:27: 36:28
         StorageLive(_6);                 // scope 0 at $DIR/match_false_edges.rs:36:14: 36:16
         _6 = ((_2 as Some).0: i32);      // scope 0 at $DIR/match_false_edges.rs:36:14: 36:16
-        _1 = const 1i32;                 // scope 2 at $DIR/match_false_edges.rs:36:32: 36:33
+        _1 = const 1_i32;                // scope 2 at $DIR/match_false_edges.rs:36:32: 36:33
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000001))
@@ -123,7 +123,7 @@ fn main() -> () {
     bb10: {
         StorageLive(_9);                 // scope 0 at $DIR/match_false_edges.rs:37:9: 37:11
         _9 = _2;                         // scope 0 at $DIR/match_false_edges.rs:37:9: 37:11
-        _1 = const 2i32;                 // scope 3 at $DIR/match_false_edges.rs:37:15: 37:16
+        _1 = const 2_i32;                // scope 3 at $DIR/match_false_edges.rs:37:15: 37:16
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000002))
@@ -161,7 +161,7 @@ fn main() -> () {
         FakeRead(ForGuardBinding, _11);  // scope 0 at $DIR/match_false_edges.rs:38:28: 38:29
         StorageLive(_10);                // scope 0 at $DIR/match_false_edges.rs:38:14: 38:15
         _10 = ((_2 as Some).0: i32);     // scope 0 at $DIR/match_false_edges.rs:38:14: 38:15
-        _1 = const 3i32;                 // scope 4 at $DIR/match_false_edges.rs:38:33: 38:34
+        _1 = const 3_i32;                // scope 4 at $DIR/match_false_edges.rs:38:33: 38:34
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000003))

src/test/mir-opt/match_test/rustc.main.SimplifyCfg-initial.after.mir

@@ -20,7 +20,7 @@ fn main() -> () {
 
     bb0: {
         StorageLive(_1);                 // scope 0 at $DIR/match_test.rs:7:9: 7:10
-        _1 = const 3i32;                 // scope 0 at $DIR/match_test.rs:7:13: 7:14
+        _1 = const 3_i32;                // scope 0 at $DIR/match_test.rs:7:13: 7:14
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000003))
@@ -39,7 +39,7 @@ fn main() -> () {
         FakeRead(ForLet, _2);            // scope 1 at $DIR/match_test.rs:8:9: 8:10
         StorageLive(_3);                 // scope 2 at $DIR/match_test.rs:12:5: 17:6
         FakeRead(ForMatchedPlace, _1);   // scope 2 at $DIR/match_test.rs:12:11: 12:12
-        _6 = Le(const 0i32, _1);         // scope 2 at $DIR/match_test.rs:13:9: 13:14
+        _6 = Le(const 0_i32, _1);        // scope 2 at $DIR/match_test.rs:13:9: 13:14
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000000))
@@ -50,7 +50,7 @@ fn main() -> () {
     }
 
     bb1: {
-        _7 = Lt(_1, const 10i32);        // scope 2 at $DIR/match_test.rs:13:9: 13:14
+        _7 = Lt(_1, const 10_i32);       // scope 2 at $DIR/match_test.rs:13:9: 13:14
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x0000000a))
@@ -65,7 +65,7 @@ fn main() -> () {
     }
 
     bb3: {
-        _3 = const 3i32;                 // scope 2 at $DIR/match_test.rs:16:14: 16:15
+        _3 = const 3_i32;                // scope 2 at $DIR/match_test.rs:16:14: 16:15
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000003))
@@ -76,7 +76,7 @@ fn main() -> () {
     }
 
     bb4: {
-        _4 = Le(const 10i32, _1);        // scope 2 at $DIR/match_test.rs:14:9: 14:16
+        _4 = Le(const 10_i32, _1);       // scope 2 at $DIR/match_test.rs:14:9: 14:16
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x0000000a))
@@ -87,7 +87,7 @@ fn main() -> () {
     }
 
     bb5: {
-        _5 = Le(_1, const 20i32);        // scope 2 at $DIR/match_test.rs:14:9: 14:16
+        _5 = Le(_1, const 20_i32);       // scope 2 at $DIR/match_test.rs:14:9: 14:16
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000014))
@@ -102,7 +102,7 @@ fn main() -> () {
     }
 
     bb7: {
-        switchInt(_1) -> [-1i32: bb8, otherwise: bb3]; // scope 2 at $DIR/match_test.rs:15:9: 15:11
+        switchInt(_1) -> [-1_i32: bb8, otherwise: bb3]; // scope 2 at $DIR/match_test.rs:15:9: 15:11
     }
 
     bb8: {
@@ -119,7 +119,7 @@ fn main() -> () {
     bb10: {
         StorageDead(_9);                 // scope 2 at $DIR/match_test.rs:13:24: 13:25
         FakeRead(ForMatchGuard, _8);     // scope 2 at $DIR/match_test.rs:13:18: 13:19
-        _3 = const 0i32;                 // scope 2 at $DIR/match_test.rs:13:23: 13:24
+        _3 = const 0_i32;                // scope 2 at $DIR/match_test.rs:13:23: 13:24
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000000))
@@ -135,7 +135,7 @@ fn main() -> () {
     }
 
     bb12: {
-        _3 = const 1i32;                 // scope 2 at $DIR/match_test.rs:14:20: 14:21
+        _3 = const 1_i32;                // scope 2 at $DIR/match_test.rs:14:20: 14:21
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000001))
@@ -146,7 +146,7 @@ fn main() -> () {
     }
 
     bb13: {
-        _3 = const 2i32;                 // scope 2 at $DIR/match_test.rs:15:15: 15:16
+        _3 = const 2_i32;                // scope 2 at $DIR/match_test.rs:15:15: 15:16
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000002))

src/test/mir-opt/no-drop-for-inactive-variant/rustc.unwrap.SimplifyCfg-elaborate-drops.after.mir

@@ -14,7 +14,7 @@ fn unwrap(_1: std::option::Option<T>) -> T {
 
     bb0: {
         _2 = discriminant(_1);           // scope 0 at $DIR/no-drop-for-inactive-variant.rs:9:9: 9:16
-        switchInt(move _2) -> [0isize: bb2, 1isize: bb4, otherwise: bb3]; // scope 0 at $DIR/no-drop-for-inactive-variant.rs:9:9: 9:16
+        switchInt(move _2) -> [0_isize: bb2, 1_isize: bb4, otherwise: bb3]; // scope 0 at $DIR/no-drop-for-inactive-variant.rs:9:9: 9:16
     }
 
     bb1 (cleanup): {

src/test/mir-opt/nrvo-simple/rustc.nrvo.RenameReturnPlace.diff

@@ -17,8 +17,8 @@
   
       bb0: {
 -         StorageLive(_2);                 // scope 0 at $DIR/nrvo-simple.rs:3:9: 3:16
--         _2 = [const 0u8; 1024];          // scope 0 at $DIR/nrvo-simple.rs:3:19: 3:28
-+         _0 = [const 0u8; 1024];          // scope 0 at $DIR/nrvo-simple.rs:3:19: 3:28
+-         _2 = [const 0_u8; 1024];         // scope 0 at $DIR/nrvo-simple.rs:3:19: 3:28
++         _0 = [const 0_u8; 1024];         // scope 0 at $DIR/nrvo-simple.rs:3:19: 3:28
                                            // ty::Const
                                            // + ty: u8
                                            // + val: Value(Scalar(0x00))

src/test/mir-opt/packed-struct-drop-aligned/32bit/rustc.main.SimplifyCfg-elaborate-drops.after.mir

@@ -16,7 +16,7 @@ fn main() -> () {
         StorageLive(_1);                 // scope 0 at $DIR/packed-struct-drop-aligned.rs:6:9: 6:14
         StorageLive(_2);                 // scope 0 at $DIR/packed-struct-drop-aligned.rs:6:24: 6:42
         StorageLive(_3);                 // scope 0 at $DIR/packed-struct-drop-aligned.rs:6:32: 6:41
-        _3 = Droppy(const 0usize);       // scope 0 at $DIR/packed-struct-drop-aligned.rs:6:32: 6:41
+        _3 = Droppy(const 0_usize);      // scope 0 at $DIR/packed-struct-drop-aligned.rs:6:32: 6:41
                                          // ty::Const
                                          // + ty: usize
                                          // + val: Value(Scalar(0x00000000))
@@ -29,7 +29,7 @@ fn main() -> () {
         StorageDead(_2);                 // scope 0 at $DIR/packed-struct-drop-aligned.rs:6:42: 6:43
         StorageLive(_4);                 // scope 1 at $DIR/packed-struct-drop-aligned.rs:7:11: 7:29
         StorageLive(_5);                 // scope 1 at $DIR/packed-struct-drop-aligned.rs:7:19: 7:28
-        _5 = Droppy(const 0usize);       // scope 1 at $DIR/packed-struct-drop-aligned.rs:7:19: 7:28
+        _5 = Droppy(const 0_usize);      // scope 1 at $DIR/packed-struct-drop-aligned.rs:7:19: 7:28
                                          // ty::Const
                                          // + ty: usize
                                          // + val: Value(Scalar(0x00000000))

src/test/mir-opt/packed-struct-drop-aligned/64bit/rustc.main.SimplifyCfg-elaborate-drops.after.mir

@@ -16,7 +16,7 @@ fn main() -> () {
         StorageLive(_1);                 // scope 0 at $DIR/packed-struct-drop-aligned.rs:6:9: 6:14
         StorageLive(_2);                 // scope 0 at $DIR/packed-struct-drop-aligned.rs:6:24: 6:42
         StorageLive(_3);                 // scope 0 at $DIR/packed-struct-drop-aligned.rs:6:32: 6:41
-        _3 = Droppy(const 0usize);       // scope 0 at $DIR/packed-struct-drop-aligned.rs:6:32: 6:41
+        _3 = Droppy(const 0_usize);      // scope 0 at $DIR/packed-struct-drop-aligned.rs:6:32: 6:41
                                          // ty::Const
                                          // + ty: usize
                                          // + val: Value(Scalar(0x0000000000000000))
@@ -29,7 +29,7 @@ fn main() -> () {
         StorageDead(_2);                 // scope 0 at $DIR/packed-struct-drop-aligned.rs:6:42: 6:43
         StorageLive(_4);                 // scope 1 at $DIR/packed-struct-drop-aligned.rs:7:11: 7:29
         StorageLive(_5);                 // scope 1 at $DIR/packed-struct-drop-aligned.rs:7:19: 7:28
-        _5 = Droppy(const 0usize);       // scope 1 at $DIR/packed-struct-drop-aligned.rs:7:19: 7:28
+        _5 = Droppy(const 0_usize);      // scope 1 at $DIR/packed-struct-drop-aligned.rs:7:19: 7:28
                                          // ty::Const
                                          // + ty: usize
                                          // + val: Value(Scalar(0x0000000000000000))

src/test/mir-opt/remove_fake_borrows/rustc.match_guard.CleanupNonCodegenStatements.diff

@@ -16,11 +16,11 @@
 -         FakeRead(ForMatchedPlace, _1);   // scope 0 at $DIR/remove_fake_borrows.rs:7:11: 7:12
 +         nop;                             // scope 0 at $DIR/remove_fake_borrows.rs:7:11: 7:12
           _3 = discriminant(_1);           // scope 0 at $DIR/remove_fake_borrows.rs:8:9: 8:16
-          switchInt(move _3) -> [1isize: bb2, otherwise: bb1]; // scope 0 at $DIR/remove_fake_borrows.rs:8:9: 8:16
+          switchInt(move _3) -> [1_isize: bb2, otherwise: bb1]; // scope 0 at $DIR/remove_fake_borrows.rs:8:9: 8:16
       }
   
       bb1: {
-          _0 = const 1i32;                 // scope 0 at $DIR/remove_fake_borrows.rs:9:14: 9:15
+          _0 = const 1_i32;                // scope 0 at $DIR/remove_fake_borrows.rs:9:14: 9:15
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x00000001))
@@ -31,7 +31,7 @@
       }
   
       bb2: {
-          switchInt((*(*((_1 as Some).0: &&i32)))) -> [0i32: bb3, otherwise: bb1]; // scope 0 at $DIR/remove_fake_borrows.rs:8:14: 8:15
+          switchInt((*(*((_1 as Some).0: &&i32)))) -> [0_i32: bb3, otherwise: bb1]; // scope 0 at $DIR/remove_fake_borrows.rs:8:14: 8:15
       }
   
       bb3: {
@@ -62,7 +62,7 @@
 +         nop;                             // scope 0 at $DIR/remove_fake_borrows.rs:8:20: 8:21
 +         nop;                             // scope 0 at $DIR/remove_fake_borrows.rs:8:20: 8:21
 +         nop;                             // scope 0 at $DIR/remove_fake_borrows.rs:8:20: 8:21
-          _0 = const 0i32;                 // scope 0 at $DIR/remove_fake_borrows.rs:8:25: 8:26
+          _0 = const 0_i32;                // scope 0 at $DIR/remove_fake_borrows.rs:8:25: 8:26
                                            // ty::Const
                                            // + ty: i32
                                            // + val: Value(Scalar(0x00000000))

src/test/mir-opt/retag/rustc.main.SimplifyCfg-elaborate-drops.after.mir

@@ -56,7 +56,7 @@ fn main() -> () {
 
     bb0: {
         StorageLive(_1);                 // scope 0 at $DIR/retag.rs:30:9: 30:14
-        _1 = const 0i32;                 // scope 0 at $DIR/retag.rs:30:17: 30:18
+        _1 = const 0_i32;                // scope 0 at $DIR/retag.rs:30:17: 30:18
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000000))
@@ -67,7 +67,7 @@ fn main() -> () {
         StorageLive(_3);                 // scope 1 at $DIR/retag.rs:32:13: 32:14
         StorageLive(_4);                 // scope 1 at $DIR/retag.rs:32:17: 32:24
         StorageLive(_5);                 // scope 1 at $DIR/retag.rs:32:17: 32:24
-        _5 = Test(const 0i32);           // scope 1 at $DIR/retag.rs:32:17: 32:24
+        _5 = Test(const 0_i32);          // scope 1 at $DIR/retag.rs:32:17: 32:24
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000000))
@@ -170,7 +170,7 @@ fn main() -> () {
         StorageLive(_19);                // scope 7 at $DIR/retag.rs:47:5: 47:24
         StorageLive(_20);                // scope 7 at $DIR/retag.rs:47:5: 47:12
         StorageLive(_21);                // scope 7 at $DIR/retag.rs:47:5: 47:12
-        _21 = Test(const 0i32);          // scope 7 at $DIR/retag.rs:47:5: 47:12
+        _21 = Test(const 0_i32);         // scope 7 at $DIR/retag.rs:47:5: 47:12
                                          // ty::Const
                                          // + ty: i32
                                          // + val: Value(Scalar(0x00000000))

src/test/mir-opt/simple-match/32bit/rustc.match_bool.mir_map.0.mir

@@ -18,7 +18,7 @@ fn match_bool(_1: bool) -> usize {
     }
 
     bb3: {
-        _0 = const 20usize;              // scope 0 at $DIR/simple-match.rs:8:14: 8:16
+        _0 = const 20_usize;             // scope 0 at $DIR/simple-match.rs:8:14: 8:16
                                          // ty::Const
                                          // + ty: usize
                                          // + val: Value(Scalar(0x00000014))
@@ -29,7 +29,7 @@ fn match_bool(_1: bool) -> usize {
     }
 
     bb4: {
-        _0 = const 10usize;              // scope 0 at $DIR/simple-match.rs:7:17: 7:19
+        _0 = const 10_usize;             // scope 0 at $DIR/simple-match.rs:7:17: 7:19
                                          // ty::Const
                                          // + ty: usize
                                          // + val: Value(Scalar(0x0000000a))

src/test/mir-opt/simple-match/64bit/rustc.match_bool.mir_map.0.mir

@@ -18,7 +18,7 @@ fn match_bool(_1: bool) -> usize {
     }
 
     bb3: {
-        _0 = const 20usize;              // scope 0 at $DIR/simple-match.rs:8:14: 8:16
+        _0 = const 20_usize;             // scope 0 at $DIR/simple-match.rs:8:14: 8:16
                                          // ty::Const
                                          // + ty: usize
                                          // + val: Value(Scalar(0x0000000000000014))
@@ -29,7 +29,7 @@ fn match_bool(_1: bool) -> usize {
     }
 
     bb4: {
-        _0 = const 10usize;              // scope 0 at $DIR/simple-match.rs:7:17: 7:19
+        _0 = const 10_usize;             // scope 0 at $DIR/simple-match.rs:7:17: 7:19
                                          // ty::Const
                                          // + ty: usize
                                          // + val: Value(Scalar(0x000000000000000a))

src/test/mir-opt/simplify-arm-identity/32bit/rustc.main.SimplifyArmIdentity.diff

@@ -19,7 +19,7 @@
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/simplify-arm-identity.rs:18:9: 18:10
-          ((_1 as Foo).0: u8) = const 0u8; // scope 0 at $DIR/simplify-arm-identity.rs:18:18: 18:29
+          ((_1 as Foo).0: u8) = const 0_u8; // scope 0 at $DIR/simplify-arm-identity.rs:18:18: 18:29
                                            // ty::Const
                                            // + ty: u8
                                            // + val: Value(Scalar(0x00))
@@ -28,7 +28,7 @@
                                            // + literal: Const { ty: u8, val: Value(Scalar(0x00)) }
           discriminant(_1) = 0;            // scope 0 at $DIR/simplify-arm-identity.rs:18:18: 18:29
           StorageLive(_2);                 // scope 1 at $DIR/simplify-arm-identity.rs:19:18: 22:6
-          _3 = const 0isize;               // scope 1 at $DIR/simplify-arm-identity.rs:20:9: 20:20
+          _3 = const 0_isize;              // scope 1 at $DIR/simplify-arm-identity.rs:20:9: 20:20
                                            // ty::Const
                                            // + ty: isize
                                            // + val: Value(Scalar(0x00000000))
@@ -39,7 +39,7 @@
       }
   
       bb1: {
-          _2 = const Dst::Foo(0u8);        // scope 1 at $DIR/simplify-arm-identity.rs:21:21: 21:32
+          _2 = const Dst::Foo(0_u8);       // scope 1 at $DIR/simplify-arm-identity.rs:21:21: 21:32
                                            // ty::Const
                                            // + ty: Dst
                                            // + val: Value(Scalar(0x00))

src/test/mir-opt/simplify-arm-identity/64bit/rustc.main.SimplifyArmIdentity.diff

@@ -19,7 +19,7 @@
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/simplify-arm-identity.rs:18:9: 18:10
-          ((_1 as Foo).0: u8) = const 0u8; // scope 0 at $DIR/simplify-arm-identity.rs:18:18: 18:29
+          ((_1 as Foo).0: u8) = const 0_u8; // scope 0 at $DIR/simplify-arm-identity.rs:18:18: 18:29
                                            // ty::Const
                                            // + ty: u8
                                            // + val: Value(Scalar(0x00))
@@ -28,7 +28,7 @@
                                            // + literal: Const { ty: u8, val: Value(Scalar(0x00)) }
           discriminant(_1) = 0;            // scope 0 at $DIR/simplify-arm-identity.rs:18:18: 18:29
           StorageLive(_2);                 // scope 1 at $DIR/simplify-arm-identity.rs:19:18: 22:6
-          _3 = const 0isize;               // scope 1 at $DIR/simplify-arm-identity.rs:20:9: 20:20
+          _3 = const 0_isize;              // scope 1 at $DIR/simplify-arm-identity.rs:20:9: 20:20
                                            // ty::Const
                                            // + ty: isize
                                            // + val: Value(Scalar(0x0000000000000000))
@@ -39,7 +39,7 @@
       }
   
       bb1: {
-          _2 = const Dst::Foo(0u8);        // scope 1 at $DIR/simplify-arm-identity.rs:21:21: 21:32
+          _2 = const Dst::Foo(0_u8);       // scope 1 at $DIR/simplify-arm-identity.rs:21:21: 21:32
                                            // ty::Const
                                            // + ty: Dst
                                            // + val: Value(Scalar(0x00))

src/test/mir-opt/simplify-arm/rustc.id.SimplifyArmIdentity.diff

@@ -13,7 +13,7 @@
   
       bb0: {
           _2 = discriminant(_1);           // scope 0 at $DIR/simplify-arm.rs:11:9: 11:16
-          switchInt(move _2) -> [0isize: bb1, 1isize: bb3, otherwise: bb2]; // scope 0 at $DIR/simplify-arm.rs:11:9: 11:16
+          switchInt(move _2) -> [0_isize: bb1, 1_isize: bb3, otherwise: bb2]; // scope 0 at $DIR/simplify-arm.rs:11:9: 11:16
       }
   
       bb1: {

src/test/mir-opt/simplify-arm/rustc.id.SimplifyBranchSame.diff

@@ -13,7 +13,7 @@
   
       bb0: {
           _2 = discriminant(_1);           // scope 0 at $DIR/simplify-arm.rs:11:9: 11:16
-          switchInt(move _2) -> [0isize: bb1, 1isize: bb3, otherwise: bb2]; // scope 0 at $DIR/simplify-arm.rs:11:9: 11:16
+          switchInt(move _2) -> [0_isize: bb1, 1_isize: bb3, otherwise: bb2]; // scope 0 at $DIR/simplify-arm.rs:11:9: 11:16
       }
   
       bb1: {