Reformat mir! macro invocations to use braces.

The `mir!` macro has multiple parts:
- An optional return type annotation.
- A sequence of zero or more local declarations.
- A mandatory starting anonymous basic block, which is brace-delimited.
- A sequence of zero of more additional named basic blocks.

Some `mir!` invocations use braces with a "block" style, like so:
```
mir! {
    let _unit: ();
    {
	let non_copy = S(42);
	let ptr = std::ptr::addr_of_mut!(non_copy);
	// Inside `callee`, the first argument and `*ptr` are basically
	// aliasing places!
	Call(_unit = callee(Move(*ptr), ptr), ReturnTo(after_call), UnwindContinue())
    }
    after_call = {
	Return()
    }
}
```
Some invocations use parens with a "block" style, like so:
```
mir!(
    let x: [i32; 2];
    let one: i32;
    {
	x = [42, 43];
	one = 1;
	x = [one, 2];
	RET = Move(x);
	Return()
    }
)
```
And some invocations uses parens with a "tighter" style, like so:
```
mir!({
    SetDiscriminant(*b, 0);
    Return()
})
```
This last style is generally used for cases where just the mandatory
starting basic block is present. Its braces are placed next to the
parens.

This commit changes all `mir!` invocations to use braces with a "block"
style. Why?

- Consistency is good.

- The contents of the invocation is a block of code, so it's odd to use
  parens. They are more normally used for function-like macros.

- Most importantly, the next commit will enable rustfmt for
  `tests/mir-opt/`. rustfmt is more aggressive about formatting macros
  that use parens than macros that use braces. Without this commit's
  changes, rustfmt would break a couple of `mir!` macro invocations that
  use braces within `tests/mir-opt` by inserting an extraneous comma.
  E.g.:
  ```
  mir!(type RET = (i32, bool);, { // extraneous comma after ';'
      RET.0 = 1;
      RET.1 = true;
      Return()
  })
  ```
  Switching those `mir!` invocations to use braces avoids that problem,
  resulting in this, which is nicer to read as well as being valid
  syntax:
  ```
  mir! {
      type RET = (i32, bool);
      {
	  RET.0 = 1;
	  RET.1 = true;
	  Return()
      }
  }
  ```

compiler/rustc_mir_transform/src/elaborate_drops.rs

@@ -34,14 +34,14 @@ use std::fmt;
 ///
 /// ```text
 // fn drop_term<T>(t: &mut T) {
-//     mir!(
+//     mir! {
 //         {
 //             Drop(*t, exit)
 //         }
 //         exit = {
 //             Return()
 //         }
-//     )
+//     }
 // }
 /// ```
 pub struct ElaborateDrops;

library/core/src/intrinsics/mir.rs

@@ -20,7 +20,7 @@
 //!
 //! #[custom_mir(dialect = "built")]
 //! pub fn simple(x: i32) -> i32 {
-//!     mir!(
+//!     mir! {
 //!         let temp2: i32;
 //!
 //!         {
@@ -33,7 +33,7 @@
 //!             RET = temp2;
 //!             Return()
 //!         }
-//!     )
+//!     }
 //! }
 //! ```
 //!
@@ -71,7 +71,7 @@
 //!
 //! #[custom_mir(dialect = "built")]
 //! pub fn choose_load(a: &i32, b: &i32, c: bool) -> i32 {
-//!     mir!(
+//!     mir! {
 //!         {
 //!             match c {
 //!                 true => t,
@@ -93,20 +93,22 @@
 //!             RET = *temp;
 //!             Return()
 //!         }
-//!     )
+//!     }
 //! }
 //!
 //! #[custom_mir(dialect = "built")]
 //! fn unwrap_unchecked<T>(opt: Option<T>) -> T {
-//!     mir!({
+//!     mir! {
-//!         RET = Move(Field(Variant(opt, 1), 0));
+//!         {
-//!         Return()
+//!             RET = Move(Field(Variant(opt, 1), 0));
-//!     })
+//!             Return()
+//!         }
+//!     }
 //! }
 //!
 //! #[custom_mir(dialect = "runtime", phase = "optimized")]
 //! fn push_and_pop<T>(v: &mut Vec<T>, value: T) {
-//!     mir!(
+//!     mir! {
 //!         let _unused;
 //!         let popped;
 //!
@@ -125,19 +127,19 @@
 //!         ret = {
 //!             Return()
 //!         }
-//!     )
+//!     }
 //! }
 //!
 //! #[custom_mir(dialect = "runtime", phase = "optimized")]
 //! fn annotated_return_type() -> (i32, bool) {
-//!     mir!(
+//!     mir! {
 //!         type RET = (i32, bool);
 //!         {
 //!             RET.0 = 1;
 //!             RET.1 = true;
 //!             Return()
 //!         }
-//!     )
+//!     }
 //! }
 //! ```
 //!
@@ -152,7 +154,7 @@
 //!
 //! #[custom_mir(dialect = "built")]
 //! fn borrow_error(should_init: bool) -> i32 {
-//!     mir!(
+//!     mir! {
 //!         let temp: i32;
 //!
 //!         {
@@ -171,7 +173,7 @@
 //!             RET = temp;
 //!             Return()
 //!         }
-//!     )
+//!     }
 //! }
 //! ```
 //!
@@ -179,7 +181,7 @@
 //! error[E0381]: used binding is possibly-uninitialized
 //!   --> test.rs:24:13
 //!    |
-//! 8  | /     mir!(
+//! 8  | /     mir! {
 //! 9  | |         let temp: i32;
 //! 10 | |
 //! 11 | |         {
@@ -191,7 +193,7 @@
 //!    | |             ^^^^^^^^^^ value used here but it is possibly-uninitialized
 //! 25 | |             Return()
 //! 26 | |         }
-//! 27 | |     )
+//! 27 | |     }
 //!    | |_____- binding declared here but left uninitialized
 //!
 //! error: aborting due to 1 previous error
@@ -407,18 +409,22 @@ define!(
     ///
     /// #[custom_mir(dialect = "built")]
     /// fn unwrap_deref(opt: Option<&i32>) -> i32 {
-    ///     mir!({
+    ///     mir! {
-    ///         RET = *Field::<&i32>(Variant(opt, 1), 0);
+    ///         {
-    ///         Return()
+    ///             RET = *Field::<&i32>(Variant(opt, 1), 0);
-    ///     })
+    ///             Return()
+    ///         }
+    ///     }
     /// }
     ///
     /// #[custom_mir(dialect = "built")]
     /// fn set(opt: &mut Option<i32>) {
-    ///     mir!({
+    ///     mir! {
-    ///         place!(Field(Variant(*opt, 1), 0)) = 5;
+    ///         {
-    ///         Return()
+    ///             place!(Field(Variant(*opt, 1), 0)) = 5;
-    ///     })
+    ///             Return()
+    ///         }
+    ///     }
     /// }
     /// ```
     fn Field<F>(place: (), field: u32) -> F
@@ -455,7 +461,7 @@ define!(
 /// your MIR into something that is easier to parse in the compiler.
 #[rustc_macro_transparency = "transparent"]
 pub macro mir {
-    (
+    {
         $(type RET = $ret_ty:ty ;)?
         $(let $local_decl:ident $(: $local_decl_ty:ty)? ;)*
         $(debug $dbg_name:ident => $dbg_data:expr ;)*
@@ -469,7 +475,7 @@ pub macro mir {
                 $($block:tt)*
             }
         )*
-    ) => {{
+    } => {{
         // First, we declare all basic blocks.
         __internal_declare_basic_blocks!($(
             $block_name $(($block_cleanup))?

src/tools/miri/tests/fail/intrinsics/ptr_metadata_uninit_slice_data.rs

@@ -7,10 +7,12 @@ use std::intrinsics::mir::*;
 
 #[custom_mir(dialect = "runtime")]
 pub unsafe fn deref_meta(p: *const *const [i32]) -> usize {
-    mir!({
+    mir! {
-        RET = PtrMetadata(*p); //~ ERROR: Undefined Behavior: using uninitialized data
+        {
-        Return()
+            RET = PtrMetadata(*p); //~ ERROR: Undefined Behavior: using uninitialized data
-    })
+            Return()
+        }
+    }
 }
 
 fn main() {

src/tools/miri/tests/fail/intrinsics/ptr_metadata_uninit_slice_data.stderr

@@ -1,8 +1,8 @@
 error: Undefined Behavior: using uninitialized data, but this operation requires initialized memory
   --> $DIR/ptr_metadata_uninit_slice_data.rs:LL:CC
    |
-LL |         RET = PtrMetadata(*p);
+LL |             RET = PtrMetadata(*p);
-   |         ^^^^^^^^^^^^^^^^^^^^^ using uninitialized data, but this operation requires initialized memory
+   |             ^^^^^^^^^^^^^^^^^^^^^ using uninitialized data, but this operation requires initialized memory
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information

src/tools/miri/tests/fail/intrinsics/ptr_metadata_uninit_slice_len.rs

@@ -7,10 +7,12 @@ use std::intrinsics::mir::*;
 
 #[custom_mir(dialect = "runtime")]
 pub unsafe fn deref_meta(p: *const *const [i32]) -> usize {
-    mir!({
+    mir! {
-        RET = PtrMetadata(*p); //~ ERROR: Undefined Behavior: using uninitialized data
+        {
-        Return()
+            RET = PtrMetadata(*p); //~ ERROR: Undefined Behavior: using uninitialized data
-    })
+            Return()
+        }
+    }
 }
 
 fn main() {

src/tools/miri/tests/fail/intrinsics/ptr_metadata_uninit_slice_len.stderr

@@ -16,8 +16,8 @@ LL |         (*p.as_mut_ptr().cast::<[*const i32; 2]>())[0] = 4 as *const i32;
 error: Undefined Behavior: using uninitialized data, but this operation requires initialized memory
   --> $DIR/ptr_metadata_uninit_slice_len.rs:LL:CC
    |
-LL |         RET = PtrMetadata(*p);
+LL |             RET = PtrMetadata(*p);
-   |         ^^^^^^^^^^^^^^^^^^^^^ using uninitialized data, but this operation requires initialized memory
+   |             ^^^^^^^^^^^^^^^^^^^^^ using uninitialized data, but this operation requires initialized memory
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information

src/tools/miri/tests/fail/intrinsics/ptr_metadata_uninit_thin.rs

@@ -7,10 +7,12 @@ use std::intrinsics::mir::*;
 
 #[custom_mir(dialect = "runtime")]
 pub unsafe fn deref_meta(p: *const *const i32) -> () {
-    mir!({
+    mir! {
-        RET = PtrMetadata(*p); //~ ERROR: Undefined Behavior: using uninitialized data
+        {
-        Return()
+            RET = PtrMetadata(*p); //~ ERROR: Undefined Behavior: using uninitialized data
-    })
+            Return()
+        }
+    }
 }
 
 fn main() {

src/tools/miri/tests/fail/intrinsics/ptr_metadata_uninit_thin.stderr

@@ -1,8 +1,8 @@
 error: Undefined Behavior: using uninitialized data, but this operation requires initialized memory
   --> $DIR/ptr_metadata_uninit_thin.rs:LL:CC
    |
-LL |         RET = PtrMetadata(*p);
+LL |             RET = PtrMetadata(*p);
-   |         ^^^^^^^^^^^^^^^^^^^^^ using uninitialized data, but this operation requires initialized memory
+   |             ^^^^^^^^^^^^^^^^^^^^^ using uninitialized data, but this operation requires initialized memory
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information

tests/mir-opt/building/custom/aggregate_exprs.rs

@@ -7,18 +7,18 @@ use core::intrinsics::mir::*;
 // EMIT_MIR aggregate_exprs.tuple.built.after.mir
 #[custom_mir(dialect = "built")]
 fn tuple() -> (i32, bool) {
-    mir!(
+    mir! {
         {
             RET = (1, true);
             Return()
         }
-    )
+    }
 }
 
 // EMIT_MIR aggregate_exprs.array.built.after.mir
 #[custom_mir(dialect = "built")]
 fn array() -> [i32; 2] {
-    mir!(
+    mir! {
         let x: [i32; 2];
         let one: i32;
         {
@@ -28,7 +28,7 @@ fn array() -> [i32; 2] {
             RET = Move(x);
             Return()
         }
-    )
+    }
 }
 
 struct Foo {
@@ -48,7 +48,7 @@ union Onion {
 // EMIT_MIR aggregate_exprs.adt.built.after.mir
 #[custom_mir(dialect = "built")]
 fn adt() -> Onion {
-    mir!(
+    mir! {
         let one: i32;
         let x: Foo;
         let y: Bar;
@@ -62,7 +62,7 @@ fn adt() -> Onion {
             RET = Onion { neon: Field(Variant(y, 0), 1) };
             Return()
         }
-    )
+    }
 }
 
 fn main() {

tests/mir-opt/building/custom/arbitrary_let.rs

@@ -8,7 +8,7 @@ use core::ptr::{addr_of, addr_of_mut};
 // EMIT_MIR arbitrary_let.arbitrary_let.built.after.mir
 #[custom_mir(dialect = "built")]
 fn arbitrary_let(x: i32) -> i32 {
-    mir!(
+    mir! {
         {
             let y = x;
             Goto(second)
@@ -21,7 +21,7 @@ fn arbitrary_let(x: i32) -> i32 {
             let z = y;
             Goto(third)
         }
-    )
+    }
 }
 
 fn main() {

tests/mir-opt/building/custom/arrays.rs

@@ -7,12 +7,14 @@ use core::intrinsics::mir::*;
 // EMIT_MIR arrays.arrays.built.after.mir
 #[custom_mir(dialect = "built")]
 fn arrays<const C: usize>() -> usize {
-    mir!({
+    mir! {
-        let x = [5_i32; C];
+        {
-        let c = Len(x);
+            let x = [5_i32; C];
-        RET = c;
+            let c = Len(x);
-        Return()
+            RET = c;
-    })
+            Return()
+        }
+    }
 }
 
 fn main() {

tests/mir-opt/building/custom/as_cast.rs

@@ -7,34 +7,34 @@ use core::intrinsics::mir::*;
 // EMIT_MIR as_cast.int_to_int.built.after.mir
 #[custom_mir(dialect = "built")]
 fn int_to_int(x: u32) -> i32 {
-    mir!(
+    mir! {
         {
             RET = x as i32;
             Return()
         }
-    )
+    }
 }
 
 // EMIT_MIR as_cast.float_to_int.built.after.mir
 #[custom_mir(dialect = "built")]
 fn float_to_int(x: f32) -> i32 {
-    mir!(
+    mir! {
         {
             RET = x as i32;
             Return()
         }
-    )
+    }
 }
 
 // EMIT_MIR as_cast.int_to_ptr.built.after.mir
 #[custom_mir(dialect = "built")]
 fn int_to_ptr(x: usize) -> *const i32 {
-    mir!(
+    mir! {
         {
             RET = x as *const i32;
             Return()
         }
-    )
+    }
 }
 
 fn main() {

tests/mir-opt/building/custom/assume.rs

@@ -7,34 +7,34 @@ use core::intrinsics::mir::*;
 // EMIT_MIR assume.assume_local.built.after.mir
 #[custom_mir(dialect = "built")]
 fn assume_local(x: bool) {
-    mir!(
+    mir! {
         {
             Assume(x);
             Return()
         }
-    )
+    }
 }
 
 // EMIT_MIR assume.assume_place.built.after.mir
 #[custom_mir(dialect = "built")]
 fn assume_place(p: (bool, u8)) {
-    mir!(
+    mir! {
         {
             Assume(p.0);
             Return()
         }
-    )
+    }
 }
 
 // EMIT_MIR assume.assume_constant.built.after.mir
 #[custom_mir(dialect = "built")]
 fn assume_constant() {
-    mir!(
+    mir! {
         {
             Assume(true);
             Return()
         }
-    )
+    }
 }
 
 fn main() {

tests/mir-opt/building/custom/composite_return.rs

@@ -7,14 +7,14 @@ use core::intrinsics::mir::*;
 // EMIT_MIR composite_return.tuple.built.after.mir
 #[custom_mir(dialect = "runtime", phase = "optimized")]
 fn tuple() -> (i32, bool) {
-    mir!(
+    mir! {
         type RET = (i32, bool);
         {
             RET.0 = 1;
             RET.1 = true;
             Return()
         }
-    )
+    }
 }
 
 fn main() {

tests/mir-opt/building/custom/consts.rs

@@ -9,14 +9,16 @@ const D: i32 = 5;
 // EMIT_MIR consts.consts.built.after.mir
 #[custom_mir(dialect = "built")]
 fn consts<const C: u32>() {
-    mir!({
+    mir! {
-        let _a = 5_u8;
+        {
-        let _b = const { 5_i8 };
+            let _a = 5_u8;
-        let _c = C;
+            let _b = const { 5_i8 };
-        let _d = D;
+            let _c = C;
-        let _e = consts::<10>;
+            let _d = D;
-        Return()
+            let _e = consts::<10>;
-    })
+            Return()
+        }
+    }
 }
 
 static S: i32 = 0x05050505;
@@ -24,11 +26,13 @@ static mut T: i32 = 0x0a0a0a0a;
 // EMIT_MIR consts.statics.built.after.mir
 #[custom_mir(dialect = "built")]
 fn statics() {
-    mir!({
+    mir! {
-        let _a: &i32 = Static(S);
+        {
-        let _b: *mut i32 = StaticMut(T);
+            let _a: &i32 = Static(S);
-        Return()
+            let _b: *mut i32 = StaticMut(T);
-    })
+            Return()
+        }
+    }
 }
 
 fn main() {

tests/mir-opt/building/custom/debuginfo.rs

@@ -7,24 +7,24 @@ use core::intrinsics::mir::*;
 // EMIT_MIR debuginfo.pointee.built.after.mir
 #[custom_mir(dialect = "built")]
 fn pointee(opt: &mut Option<i32>) {
-    mir!(
+    mir! {
         debug foo => Field::<i32>(Variant(*opt, 1), 0);
         {
             Return()
         }
-    )
+    }
 }
 
 // EMIT_MIR debuginfo.numbered.built.after.mir
 #[custom_mir(dialect = "analysis", phase = "post-cleanup")]
 fn numbered(i: (u32, i32)) {
-    mir!(
+    mir! {
         debug first => i.0;
         debug second => i.0;
         {
             Return()
         }
-    )
+    }
 }
 
 struct S { x: f32 }
@@ -32,35 +32,35 @@ struct S { x: f32 }
 // EMIT_MIR debuginfo.structured.built.after.mir
 #[custom_mir(dialect = "analysis", phase = "post-cleanup")]
 fn structured(i: S) {
-    mir!(
+    mir! {
         debug x => i.x;
         {
             Return()
         }
-    )
+    }
 }
 
 // EMIT_MIR debuginfo.variant.built.after.mir
 #[custom_mir(dialect = "built")]
 fn variant(opt: Option<i32>) {
-    mir!(
+    mir! {
         debug inner => Field::<i32>(Variant(opt, 1), 0);
         {
             Return()
         }
-    )
+    }
 }
 
 // EMIT_MIR debuginfo.variant_deref.built.after.mir
 #[custom_mir(dialect = "built")]
 fn variant_deref(opt: Option<&i32>) {
-    mir!(
+    mir! {
         debug pointer => Field::<&i32>(Variant(opt, 1), 0);
         debug deref => *Field::<&i32>(Variant(opt, 1), 0);
         {
             Return()
         }
-    )
+    }
 }
 
 fn main() {

tests/mir-opt/building/custom/enums.rs

@@ -7,7 +7,7 @@ use core::intrinsics::mir::*;
 // EMIT_MIR enums.switch_bool.built.after.mir
 #[custom_mir(dialect = "built")]
 pub fn switch_bool(b: bool) -> u32 {
-    mir!(
+    mir! {
         {
             match b {
                 true => t,
@@ -25,13 +25,13 @@ pub fn switch_bool(b: bool) -> u32 {
             RET = 10;
             Return()
         }
-    )
+    }
 }
 
 // EMIT_MIR enums.switch_option.built.after.mir
 #[custom_mir(dialect = "built")]
 pub fn switch_option(option: Option<()>) -> bool {
-    mir!(
+    mir! {
         {
             let discr = Discriminant(option);
             match discr {
@@ -50,7 +50,7 @@ pub fn switch_option(option: Option<()>) -> bool {
             RET = true;
             Return()
         }
-    )
+    }
 }
 
 #[repr(u8)]
@@ -62,7 +62,7 @@ enum Bool {
 // EMIT_MIR enums.switch_option_repr.built.after.mir
 #[custom_mir(dialect = "built")]
 fn switch_option_repr(option: Bool) -> bool {
-    mir!(
+    mir! {
         {
             let discr = Discriminant(option);
             match discr {
@@ -80,26 +80,30 @@ fn switch_option_repr(option: Bool) -> bool {
             RET = false;
             Return()
         }
-    )
+    }
 }
 
 // EMIT_MIR enums.set_discr.built.after.mir
 #[custom_mir(dialect = "runtime", phase = "initial")]
 fn set_discr(option: &mut Option<()>) {
-    mir!({
+    mir! {
-        Deinit(*option);
+        {
-        SetDiscriminant(*option, 0);
+            Deinit(*option);
-        Return()
+            SetDiscriminant(*option, 0);
-    })
+            Return()
+        }
+    }
 }
 
 // EMIT_MIR enums.set_discr_repr.built.after.mir
 #[custom_mir(dialect = "runtime", phase = "initial")]
 fn set_discr_repr(b: &mut Bool) {
-    mir!({
+    mir! {
-        SetDiscriminant(*b, 0);
+        {
-        Return()
+            SetDiscriminant(*b, 0);
-    })
+            Return()
+        }
+    }
 }
 
 fn main() {

tests/mir-opt/building/custom/operators.rs

@@ -6,37 +6,41 @@ use std::intrinsics::mir::*;
 // EMIT_MIR operators.f.built.after.mir
 #[custom_mir(dialect = "built")]
 pub fn f(a: i32, b: bool) -> i32 {
-    mir!({
+    mir! {
-        a = -a;
+        {
-        b = !b;
+            a = -a;
-        a = a + a;
+            b = !b;
-        a = a - a;
+            a = a + a;
-        a = a * a;
+            a = a - a;
-        a = a / a;
+            a = a * a;
-        a = a % a;
+            a = a / a;
-        a = a ^ a;
+            a = a % a;
-        a = a & a;
+            a = a ^ a;
-        a = a << a;
+            a = a & a;
-        a = a >> a;
+            a = a << a;
-        b = a == a;
+            a = a >> a;
-        b = a < a;
+            b = a == a;
-        b = a <= a;
+            b = a < a;
-        b = a >= a;
+            b = a <= a;
-        b = a > a;
+            b = a >= a;
-        let res = Checked(a + a);
+            b = a > a;
-        b = res.1;
+            let res = Checked(a + a);
-        a = res.0;
+            b = res.1;
-        RET = a;
+            a = res.0;
-        Return()
+            RET = a;
-    })
+            Return()
+        }
+    }
 }
 
 // EMIT_MIR operators.g.runtime.after.mir
 #[custom_mir(dialect = "runtime")]
 pub fn g(p: *const i32, q: *const [i32]) {
-    mir!({
+    mir! {
-        let a = PtrMetadata(p);
+        {
-        let b = PtrMetadata(q);
+            let a = PtrMetadata(p);
-        Return()
+            let b = PtrMetadata(q);
-    })
+            Return()
+        }
+    }
 }

tests/mir-opt/building/custom/projections.rs

@@ -12,74 +12,84 @@ union U {
 // EMIT_MIR projections.unions.built.after.mir
 #[custom_mir(dialect = "built")]
 fn unions(u: U) -> i32 {
-    mir!({
+    mir! {
-        RET = u.a;
+        {
-        Return()
+            RET = u.a;
-    })
+            Return()
+        }
+    }
 }
 
 // EMIT_MIR projections.tuples.built.after.mir
 #[custom_mir(dialect = "analysis", phase = "post-cleanup")]
 fn tuples(i: (u32, i32)) -> (u32, i32) {
-    mir!(
+    mir! {
         type RET = (u32, i32);
         {
             RET.0 = i.0;
             RET.1 = i.1;
             Return()
         }
-    )
+    }
 }
 
 // EMIT_MIR projections.unwrap.built.after.mir
 #[custom_mir(dialect = "built")]
 fn unwrap(opt: Option<i32>) -> i32 {
-    mir!({
+    mir! {
-        RET = Field(Variant(opt, 1), 0);
+        {
-        Return()
+            RET = Field(Variant(opt, 1), 0);
-    })
+            Return()
+        }
+    }
 }
 
 // EMIT_MIR projections.unwrap_deref.built.after.mir
 #[custom_mir(dialect = "built")]
 fn unwrap_deref(opt: Option<&i32>) -> i32 {
-    mir!({
+    mir! {
-        RET = *Field::<&i32>(Variant(opt, 1), 0);
+        {
-        Return()
+            RET = *Field::<&i32>(Variant(opt, 1), 0);
-    })
+            Return()
+        }
+    }
 }
 
 // EMIT_MIR projections.set.built.after.mir
 #[custom_mir(dialect = "built")]
 fn set(opt: &mut Option<i32>) {
-    mir!({
+    mir! {
-        place!(Field(Variant(*opt, 1), 0)) = 10;
+        {
-        Return()
+            place!(Field(Variant(*opt, 1), 0)) = 10;
-    })
+            Return()
+        }
+    }
 }
 
 // EMIT_MIR projections.simple_index.built.after.mir
 #[custom_mir(dialect = "built")]
 fn simple_index(a: [i32; 10], b: &[i32]) -> i32 {
-    mir!({
+    mir! {
-        let temp = 3;
+        {
-        RET = a[temp];
+            let temp = 3;
-        RET = (*b)[temp];
+            RET = a[temp];
-        Return()
+            RET = (*b)[temp];
-    })
+            Return()
+        }
+    }
 }
 
 // EMIT_MIR projections.copy_for_deref.built.after.mir
 #[custom_mir(dialect = "runtime", phase = "initial")]
 fn copy_for_deref(x: (&i32, i32)) -> i32 {
-    mir!(
+    mir! {
         let temp: &i32;
         {
             temp = CopyForDeref(x.0);
             RET = *temp;
             Return()
         }
-    )
+    }
 }
 
 fn main() {

tests/mir-opt/building/custom/references.rs

@@ -8,31 +8,29 @@ use core::ptr::{addr_of, addr_of_mut};
 // EMIT_MIR references.mut_ref.built.after.mir
 #[custom_mir(dialect = "runtime", phase = "optimized")]
 pub fn mut_ref(x: &mut i32) -> &mut i32 {
-    mir!(
+    mir! {
         let t: *mut i32;
-
         {
             t = addr_of_mut!(*x);
             RET = &mut *t;
             Retag(RET);
             Return()
         }
-    )
+    }
 }
 
 // EMIT_MIR references.immut_ref.built.after.mir
 #[custom_mir(dialect = "runtime", phase = "optimized")]
 pub fn immut_ref(x: &i32) -> &i32 {
-    mir!(
+    mir! {
         let t: *const i32;
-
         {
             t = addr_of!(*x);
             RET = & *t;
             Retag(RET);
             Return()
         }
-    )
+    }
 }
 
 // EMIT_MIR references.raw_pointer.built.after.mir
@@ -40,19 +38,23 @@ pub fn immut_ref(x: &i32) -> &i32 {
 pub fn raw_pointer(x: *const i32) -> *const i32 {
     // Regression test for a bug in which unsafetyck was not correctly turned off for
     // `dialect = "built"`
-    mir!({
+    mir! {
-        RET = addr_of!(*x);
+        {
-        Return()
+            RET = addr_of!(*x);
-    })
+            Return()
+        }
+    }
 }
 
 // EMIT_MIR references.raw_pointer_offset.built.after.mir
 #[custom_mir(dialect = "built")]
 pub fn raw_pointer_offset(x: *const i32) -> *const i32 {
-    mir!({
+    mir! {
-        RET = Offset(x, 1_isize);
+        {
-        Return()
+            RET = Offset(x, 1_isize);
-    })
+            Return()
+        }
+    }
 }
 
 fn main() {

tests/mir-opt/building/custom/simple_assign.rs

@@ -7,32 +7,32 @@ use core::intrinsics::mir::*;
 // EMIT_MIR simple_assign.simple.built.after.mir
 #[custom_mir(dialect = "built")]
 pub fn simple(x: i32) -> i32 {
-    mir!(
+    mir! {
         let temp1: i32;
         let temp2: _;
-
         {
             StorageLive(temp1);
             temp1 = x;
             Goto(exit)
         }
-
         exit = {
             temp2 = Move(temp1);
             StorageDead(temp1);
             RET = temp2;
             Return()
         }
-    )
+    }
 }
 
 // EMIT_MIR simple_assign.simple_ref.built.after.mir
 #[custom_mir(dialect = "built")]
 pub fn simple_ref(x: &mut i32) -> &mut i32 {
-    mir!({
+    mir! {
-        RET = Move(x);
+        {
-        Return()
+            RET = Move(x);
-    })
+            Return()
+        }
+    }
 }
 
 fn main() {

tests/mir-opt/building/custom/terminators.rs

@@ -11,7 +11,7 @@ fn ident<T>(t: T) -> T {
 // EMIT_MIR terminators.direct_call.built.after.mir
 #[custom_mir(dialect = "built")]
 fn direct_call(x: i32) -> i32 {
-    mir!(
+    mir! {
         {
             Call(RET = ident(x), ReturnTo(retblock), UnwindContinue())
         }
@@ -19,21 +19,20 @@ fn direct_call(x: i32) -> i32 {
         retblock = {
             Return()
         }
-    )
+    }
 }
 
 // EMIT_MIR terminators.indirect_call.built.after.mir
 #[custom_mir(dialect = "built")]
 fn indirect_call(x: i32, f: fn(i32) -> i32) -> i32 {
-    mir!(
+    mir! {
         {
             Call(RET = f(x), ReturnTo(retblock), UnwindContinue())
         }
-
         retblock = {
             Return()
         }
-    )
+    }
 }
 
 struct WriteOnDrop<'a>(&'a mut i32, i32);
@@ -47,51 +46,47 @@ impl<'a> Drop for WriteOnDrop<'a> {
 // EMIT_MIR terminators.drop_first.built.after.mir
 #[custom_mir(dialect = "built")]
 fn drop_first<'a>(a: WriteOnDrop<'a>, b: WriteOnDrop<'a>) {
-    mir!(
+    mir! {
         {
             Drop(a, ReturnTo(retblock), UnwindContinue())
         }
-
         retblock = {
             a = Move(b);
             Return()
         }
-    )
+    }
 }
 
 // EMIT_MIR terminators.drop_second.built.after.mir
 #[custom_mir(dialect = "built")]
 fn drop_second<'a>(a: WriteOnDrop<'a>, b: WriteOnDrop<'a>) {
-    mir!(
+    mir! {
         {
             Drop(b, ReturnTo(retblock), UnwindContinue())
         }
-
         retblock = {
             Return()
         }
-    )
+    }
 }
 
 // EMIT_MIR terminators.assert_nonzero.built.after.mir
 #[custom_mir(dialect = "built")]
 fn assert_nonzero(a: i32) {
-    mir!(
+    mir! {
         {
             match a {
                 0 => unreachable,
                 _ => retblock
             }
         }
-
         unreachable = {
             Unreachable()
         }
-
         retblock = {
             Return()
         }
-    )
+    }
 }
 
 fn main() {

tests/mir-opt/building/custom/unwind_action.rs

@@ -9,14 +9,14 @@ use core::intrinsics::mir::*;
 // CHECK-NEXT:  a() -> [return: bb1, unwind unreachable];
 #[custom_mir(dialect = "runtime", phase = "optimized")]
 pub fn a() {
-    mir!(
+    mir! {
         {
             Call(RET = a(), ReturnTo(bb1), UnwindUnreachable())
         }
         bb1 = {
             Return()
         }
-    )
+    }
 }
 
 // CHECK-LABEL: fn b()
@@ -24,14 +24,14 @@ pub fn a() {
 // CHECK-NEXT:  b() -> [return: bb1, unwind continue];
 #[custom_mir(dialect = "runtime", phase = "optimized")]
 pub fn b() {
-    mir!(
+    mir! {
         {
             Call(RET = b(), ReturnTo(bb1), UnwindContinue())
         }
         bb1 = {
             Return()
         }
-    )
+    }
 }
 
 // CHECK-LABEL: fn c()
@@ -39,14 +39,14 @@ pub fn b() {
 // CHECK-NEXT:  c() -> [return: bb1, unwind terminate(abi)];
 #[custom_mir(dialect = "runtime", phase = "optimized")]
 pub fn c() {
-    mir!(
+    mir! {
         {
             Call(RET = c(), ReturnTo(bb1), UnwindTerminate(ReasonAbi))
         }
         bb1 = {
             Return()
         }
-    )
+    }
 }
 
 // CHECK-LABEL: fn d()
@@ -54,7 +54,7 @@ pub fn c() {
 // CHECK-NEXT:  d() -> [return: bb1, unwind: bb2];
 #[custom_mir(dialect = "runtime", phase = "optimized")]
 pub fn d() {
-    mir!(
+    mir! {
         {
             Call(RET = d(), ReturnTo(bb1), UnwindCleanup(bb2))
         }
@@ -64,5 +64,5 @@ pub fn d() {
         bb2 (cleanup) = {
             UnwindResume()
         }
-    )
+    }
 }

tests/mir-opt/building/custom/unwind_terminate.rs

@@ -8,14 +8,14 @@ use core::intrinsics::mir::*;
 // CHECK-NEXT:  terminate(abi);
 #[custom_mir(dialect = "runtime", phase = "optimized")]
 pub fn f() {
-    mir!(
+    mir! {
         {
             Return()
         }
         bb1(cleanup) = {
             UnwindTerminate(ReasonAbi)
         }
-    )
+    }
 }
 
 // CHECK-LABEL: fn g()
@@ -23,12 +23,12 @@ pub fn f() {
 // CHECK-NEXT:  terminate(cleanup);
 #[custom_mir(dialect = "runtime", phase = "optimized")]
 pub fn g() {
-    mir!(
+    mir! {
         {
             Return()
         }
         bb1(cleanup) = {
             UnwindTerminate(ReasonInCleanup)
         }
-    )
+    }
 }

tests/mir-opt/copy-prop/borrowed_local.rs

@@ -24,7 +24,7 @@ fn compare_address() -> bool {
     // CHECK-NEXT: _0 = cmp_ref(_2, _4)
     // CHECK: bb1: {
     // CHECK-NEXT: _0 = opaque::<u8>(_3)
-    mir!(
+    mir! {
         {
             let a = 5_u8;
             let r1 = &a;
@@ -40,7 +40,7 @@ fn compare_address() -> bool {
         ret = {
             Return()
         }
-    )
+    }
 }
 
 /// Generic type `T` is `Freeze`, so shared borrows are immutable.
@@ -52,7 +52,7 @@ fn borrowed<T: Copy + Freeze>(x: T) -> bool {
     // CHECK-NEXT: _0 = opaque::<&T>(_3)
     // CHECK: bb1: {
     // CHECK-NEXT: _0 = opaque::<T>(_1)
-    mir!(
+    mir! {
         {
             let a = x;
             let r1 = &x;
@@ -64,7 +64,7 @@ fn borrowed<T: Copy + Freeze>(x: T) -> bool {
         ret = {
             Return()
         }
-    )
+    }
 }
 
 /// Generic type `T` is not known to be `Freeze`, so shared borrows may be mutable.
@@ -77,7 +77,7 @@ fn non_freeze<T: Copy>(x: T) -> bool {
     // CHECK-NEXT: _0 = opaque::<&T>(_3)
     // CHECK: bb1: {
     // CHECK-NEXT: _0 = opaque::<T>(_2)
-    mir!(
+    mir! {
         {
             let a = x;
             let r1 = &x;
@@ -89,7 +89,7 @@ fn non_freeze<T: Copy>(x: T) -> bool {
         ret = {
             Return()
         }
-    )
+    }
 }
 
 fn main() {

tests/mir-opt/copy-prop/custom_move_arg.rs

@@ -12,17 +12,19 @@ struct NotCopy(bool);
 // EMIT_MIR custom_move_arg.f.CopyProp.diff
 #[custom_mir(dialect = "runtime")]
 fn f(_1: NotCopy) {
-    mir!({
+    mir! {
-        let _2 = _1;
+        {
-        Call(RET = opaque(Move(_1)), ReturnTo(bb1), UnwindUnreachable())
+            let _2 = _1;
+            Call(RET = opaque(Move(_1)), ReturnTo(bb1), UnwindUnreachable())
+        }
+        bb1 = {
+            let _3 = Move(_2);
+            Call(RET = opaque(_3), ReturnTo(bb2), UnwindUnreachable())
+        }
+        bb2 = {
+            Return()
+        }
     }
-    bb1 = {
-        let _3 = Move(_2);
-        Call(RET = opaque(_3), ReturnTo(bb2), UnwindUnreachable())
-    }
-    bb2 = {
-        Return()
-    })
 }
 
 #[inline(never)]

tests/mir-opt/copy-prop/move_projection.rs

@@ -13,7 +13,7 @@ struct Foo(u8);
 
 #[custom_mir(dialect = "runtime")]
 fn f(a: Foo) -> bool {
-    mir!(
+    mir! {
         {
             let b = a;
             // This is a move out of a copy, so must become a copy of `a.0`.
@@ -26,7 +26,7 @@ fn f(a: Foo) -> bool {
         ret = {
             Return()
         }
-    )
+    }
 }
 
 fn main() {

tests/mir-opt/copy-prop/mutate_through_pointer.rs

@@ -18,14 +18,16 @@ use core::intrinsics::mir::*;
 
 #[custom_mir(dialect = "analysis", phase = "post-cleanup")]
 fn f(c: bool) -> bool {
-    mir!({
+    mir! {
-        let a = c;
+        {
-        let p = core::ptr::addr_of!(a);
+            let a = c;
-        let p2 = core::ptr::addr_of_mut!(*p);
+            let p = core::ptr::addr_of!(a);
-        *p2 = false;
+            let p2 = core::ptr::addr_of_mut!(*p);
-        RET = c;
+            *p2 = false;
-        Return()
+            RET = c;
-    })
+            Return()
+        }
+    }
 }
 
 fn main() {

tests/mir-opt/copy-prop/non_dominate.rs

@@ -8,16 +8,28 @@ use core::intrinsics::mir::*;
 
 #[custom_mir(dialect = "analysis", phase = "post-cleanup")]
 fn f(c: bool) -> bool {
-    mir!(
+    mir! {
         let a: bool;
         let b: bool;
-        { Goto(bb1) }
+        {
-        bb1 = { b = c; match b { false => bb3, _ => bb2 }}
+            Goto(bb1)
+        }
+        bb1 = {
+            b = c;
+            match b { false => bb3, _ => bb2 }
+        }
         // This assignment to `a` does not dominate the use in `bb3`.
         // It should not be replaced by `b`.
-        bb2 = { a = b; c = false; Goto(bb1) }
+        bb2 = {
-        bb3 = { RET = a; Return() }
+            a = b;
-    )
+            c = false;
+            Goto(bb1)
+        }
+        bb3 = {
+            RET = a;
+            Return()
+        }
+    }
 }
 
 fn main() {

tests/mir-opt/dataflow-const-prop/enum.rs

@@ -84,7 +84,7 @@ struct NonZeroUsize(usize);
 // CHECK-LABEL: fn mutate_discriminant(
 #[custom_mir(dialect = "runtime", phase = "post-cleanup")]
 fn mutate_discriminant() -> u8 {
-    mir!(
+    mir! {
         let x: Option<NonZeroUsize>;
         {
             SetDiscriminant(x, 1);
@@ -109,7 +109,7 @@ fn mutate_discriminant() -> u8 {
             RET = 2;
             Unreachable()
         }
-    )
+    }
 }
 
 // EMIT_MIR enum.multiple.DataflowConstProp.diff

tests/mir-opt/dead-store-elimination/call_arg_copy.rs

@@ -29,7 +29,7 @@ struct Packed {
 fn move_packed(packed: Packed) {
     // CHECK-LABEL: fn move_packed(
     // CHECK: = use_both(const 0_i32, (_1.1: i32))
-    mir!(
+    mir! {
         {
             // We have a packed struct, verify that the copy is not turned into a move.
             Call(RET = use_both(0, packed.y), ReturnTo(ret), UnwindContinue())
@@ -37,7 +37,7 @@ fn move_packed(packed: Packed) {
         ret = {
             Return()
         }
-    )
+    }
 }
 
 fn main() {

tests/mir-opt/dead-store-elimination/cycle.rs

@@ -20,7 +20,7 @@ fn cycle(mut x: i32, mut y: i32, mut z: i32) {
     // CHECK-NOT: {{_.*}} = move {{_.*}};
 
     // We use custom MIR to avoid generating debuginfo, that would force to preserve writes.
-    mir!(
+    mir! {
         let condition: bool;
         {
             Call(condition = cond(), ReturnTo(bb1), UnwindContinue())
@@ -38,7 +38,7 @@ fn cycle(mut x: i32, mut y: i32, mut z: i32) {
         ret = {
             Return()
         }
-    )
+    }
 }
 
 fn main() {

tests/mir-opt/gvn.rs

@@ -539,7 +539,7 @@ fn slices() {
 #[custom_mir(dialect = "analysis")]
 fn duplicate_slice() -> (bool, bool) {
     // CHECK-LABEL: fn duplicate_slice(
-    mir!(
+    mir! {
         let au: u128;
         let bu: u128;
         let cu: u128;
@@ -585,7 +585,7 @@ fn duplicate_slice() -> (bool, bool) {
             RET = (direct, indirect);
             Return()
         }
-    )
+    }
 }
 
 fn repeat() {
@@ -623,11 +623,13 @@ fn fn_pointers() {
 fn indirect_static() {
     static A: Option<u8> = None;
 
-    mir!({
+    mir! {
-        let ptr = Static(A);
+        {
-        let out = Field::<u8>(Variant(*ptr, 1), 0);
+            let ptr = Static(A);
-        Return()
+            let out = Field::<u8>(Variant(*ptr, 1), 0);
-    })
+            Return()
+        }
+    }
 }
 
 /// Verify that having constant index `u64::MAX` does not yield to an overflow in rustc.
@@ -733,7 +735,7 @@ fn borrowed<T: Copy + Freeze>(x: T) {
     // CHECK-NEXT: _0 = opaque::<T>(_1)
     // CHECK: bb2: {
     // CHECK-NEXT: _0 = opaque::<T>(_1)
-    mir!(
+    mir! {
         {
             let a = x;
             let r1 = &x;
@@ -748,7 +750,7 @@ fn borrowed<T: Copy + Freeze>(x: T) {
         ret = {
             Return()
         }
-    )
+    }
 }
 
 /// Generic type `T` is not known to be `Freeze`, so shared borrows may be mutable.
@@ -763,7 +765,7 @@ fn non_freeze<T: Copy>(x: T) {
     // CHECK-NEXT: _0 = opaque::<T>(_2)
     // CHECK: bb2: {
     // CHECK-NEXT: _0 = opaque::<T>((*_3))
-    mir!(
+    mir! {
         {
             let a = x;
             let r1 = &x;
@@ -778,7 +780,7 @@ fn non_freeze<T: Copy>(x: T) {
         ret = {
             Return()
         }
-    )
+    }
 }
 
 fn main() {

tests/mir-opt/instsimplify/duplicate_switch_targets.rs

@@ -10,7 +10,7 @@ use std::intrinsics::mir::*;
 pub unsafe fn assert_zero(x: u8) -> u8 {
     // CHECK-LABEL: fn assert_zero(
     // CHECK: switchInt({{.*}}) -> [0: {{bb.*}}, otherwise: {{bb.*}}]
-    mir!(
+    mir! {
         {
             match x {
                 0 => retblock,
@@ -25,5 +25,5 @@ pub unsafe fn assert_zero(x: u8) -> u8 {
             RET = x;
             Return()
         }
-    )
+    }
 }

tests/mir-opt/jump_threading.rs

@@ -157,7 +157,7 @@ fn custom_discr(x: bool) -> u8 {
 #[custom_mir(dialect = "runtime", phase = "post-cleanup")]
 fn multiple_match(x: u8) -> u8 {
     // CHECK-LABEL: fn multiple_match(
-    mir!(
+    mir! {
         {
             // CHECK: bb0: {
             // CHECK:     switchInt([[x:_.*]]) -> [3: bb1, otherwise: bb2];
@@ -220,7 +220,7 @@ fn multiple_match(x: u8) -> u8 {
             RET = 11;
             Return()
         }
-    )
+    }
 }
 
 /// Both 1-3-4 and 2-3-4 are threadable. As 1 and 2 are the only predecessors of 3,
@@ -228,7 +228,7 @@ fn multiple_match(x: u8) -> u8 {
 #[custom_mir(dialect = "runtime", phase = "post-cleanup")]
 fn duplicate_chain(x: bool) -> u8 {
     // CHECK-LABEL: fn duplicate_chain(
-    mir!(
+    mir! {
         let a: u8;
         {
             // CHECK: bb0: {
@@ -278,7 +278,7 @@ fn duplicate_chain(x: bool) -> u8 {
             RET = 9;
             Return()
         }
-    )
+    }
 }
 
 #[rustc_layout_scalar_valid_range_start(1)]
@@ -292,7 +292,7 @@ fn mutate_discriminant() -> u8 {
     // CHECK-NOT: goto -> {{bb.*}};
     // CHECK: switchInt(
     // CHECK-NOT: goto -> {{bb.*}};
-    mir!(
+    mir! {
         let x: Option<NonZeroUsize>;
         {
             SetDiscriminant(x, 1);
@@ -313,7 +313,7 @@ fn mutate_discriminant() -> u8 {
             RET = 2;
             Unreachable()
         }
-    )
+    }
 }
 
 /// Verify that we do not try to reason when there are mutable pointers involved.
@@ -342,7 +342,7 @@ fn mutable_ref() -> bool {
 #[custom_mir(dialect = "runtime", phase = "post-cleanup")]
 fn renumbered_bb(x: bool) -> u8 {
     // CHECK-LABEL: fn renumbered_bb(
-    mir!(
+    mir! {
         let a: bool;
         let b: bool;
         {
@@ -398,7 +398,7 @@ fn renumbered_bb(x: bool) -> u8 {
         // Duplicate of bb4.
         // CHECK: bb9: {
         // CHECK-NEXT: goto -> bb6;
-    )
+    }
 }
 
 /// This function has 3 TOs: 1-4-5, 0-1-4-7-5-8 and 3-4-7-5-6
@@ -408,7 +408,7 @@ fn renumbered_bb(x: bool) -> u8 {
 #[custom_mir(dialect = "runtime", phase = "post-cleanup")]
 fn disappearing_bb(x: u8) -> u8 {
     // CHECK-LABEL: fn disappearing_bb(
-    mir!(
+    mir! {
         let a: bool;
         let b: bool;
         {
@@ -450,7 +450,7 @@ fn disappearing_bb(x: u8) -> u8 {
         // CHECK: goto -> bb5;
         // CHECK: bb10: {
         // CHECK: goto -> bb6;
-    )
+    }
 }
 
 /// Verify that we can thread jumps when we assign from an aggregate constant.
@@ -472,7 +472,7 @@ fn aggregate(x: u8) -> u8 {
 #[custom_mir(dialect = "runtime", phase = "post-cleanup")]
 fn assume(a: u8, b: bool) -> u8 {
     // CHECK-LABEL: fn assume(
-    mir!(
+    mir! {
         {
             // CHECK: bb0: {
             // CHECK-NEXT: switchInt(_1) -> [7: bb1, otherwise: bb2]
@@ -511,7 +511,7 @@ fn assume(a: u8, b: bool) -> u8 {
         }
         // CHECK: bb6: {
         // CHECK-NEXT: goto -> bb5;
-    )
+    }
 }
 
 fn main() {

tests/mir-opt/matches_reduce_branches.rs

@@ -88,7 +88,7 @@ fn match_u8_i16(i: EnumAu8) -> i16 {
 fn match_u8_i16_2(i: EnumAu8) -> i16 {
     // CHECK-LABEL: fn match_u8_i16_2(
     // CHECK: switchInt
-    mir!(
+    mir! {
         {
             let a = Discriminant(i);
             match a {
@@ -110,7 +110,7 @@ fn match_u8_i16_2(i: EnumAu8) -> i16 {
         ret = {
             Return()
         }
-    )
+    }
 }
 
 // EMIT_MIR matches_reduce_branches.match_u8_i16_failed.MatchBranchSimplification.diff
@@ -158,7 +158,7 @@ fn match_u8_u16(i: EnumBu8) -> u16 {
 fn match_u8_u16_2(i: EnumBu8) -> i16 {
     // CHECK-LABEL: fn match_u8_u16_2(
     // CHECK: switchInt
-    mir!(
+    mir! {
         {
             let a = Discriminant(i);
             match a {
@@ -187,7 +187,7 @@ fn match_u8_u16_2(i: EnumBu8) -> i16 {
         ret = {
             Return()
         }
-    )
+    }
 }
 
 #[repr(i8)]

tests/mir-opt/nrvo_miscompile_111005.rs

@@ -10,12 +10,14 @@ use core::intrinsics::mir::*;
 // EMIT_MIR nrvo_miscompile_111005.wrong.RenameReturnPlace.diff
 #[custom_mir(dialect = "runtime", phase = "initial")]
 pub fn wrong(arg: char) -> char {
-    mir!({
+    mir! {
-        let temp = arg;
+        {
-        RET = temp;
+            let temp = arg;
-        temp = 'b';
+            RET = temp;
-        Return()
+            temp = 'b';
-    })
+            Return()
+        }
+    }
 }
 
 fn main() {

tests/mir-opt/reference_prop.rs

@@ -658,7 +658,7 @@ fn read_through_raw(x: &mut usize) -> usize {
     // CHECK-NEXT: return;
 
     use std::intrinsics::mir::*;
-    mir!(
+    mir! {
         let r1: &mut usize;
         let r2: &mut usize;
         let p1: *mut usize;
@@ -674,7 +674,7 @@ fn read_through_raw(x: &mut usize) -> usize {
             RET = *p2;
             Return()
         }
-    )
+    }
 }
 
 #[custom_mir(dialect = "runtime", phase = "post-cleanup")]
@@ -683,7 +683,7 @@ fn multiple_storage() {
     // CHECK: _3 = (*_2);
 
     use std::intrinsics::mir::*;
-    mir!(
+    mir! {
         let x: i32;
         {
             StorageLive(x);
@@ -700,7 +700,7 @@ fn multiple_storage() {
         retblock = {
             Return()
         }
-    )
+    }
 }
 
 #[custom_mir(dialect = "runtime", phase = "post-cleanup")]
@@ -709,7 +709,7 @@ fn dominate_storage() {
     // CHECK: _5 = (*_2);
 
     use std::intrinsics::mir::*;
-    mir!(
+    mir! {
         let x: i32;
         let r: &i32;
         let c: i32;
@@ -730,7 +730,7 @@ fn dominate_storage() {
             let d = true;
             match d { false => bb2, _ => bb0 }
         }
-    )
+    }
 }
 
 #[custom_mir(dialect = "runtime", phase = "post-cleanup")]
@@ -739,7 +739,7 @@ fn maybe_dead(m: bool) {
     // CHECK: (*_5) = const 7_i32;
 
     use std::intrinsics::mir::*;
-    mir!(
+    mir! {
         let x: i32;
         let y: i32;
         {
@@ -774,7 +774,7 @@ fn maybe_dead(m: bool) {
         retblock = {
             Return()
         }
-    )
+    }
 }
 
 fn mut_raw_then_mut_shr() -> (i32, i32) {

tests/mir-opt/set_no_discriminant.rs

@@ -19,7 +19,7 @@ pub fn f() -> usize {
     // CHECK-NOT: goto
     // CHECK: switchInt(
     // CHECK-NOT: goto
-    mir!(
+    mir! {
         let a: isize;
         let e: E<char>;
         {
@@ -39,7 +39,7 @@ pub fn f() -> usize {
             RET = 1;
             Return()
         }
-    )
+    }
 }
 
 // EMIT_MIR set_no_discriminant.generic.JumpThreading.diff
@@ -49,7 +49,7 @@ pub fn generic<T>() -> usize {
     // CHECK-NOT: goto
     // CHECK: switchInt(
     // CHECK-NOT: goto
-    mir!(
+    mir! {
         let a: isize;
         let e: E<T>;
         {
@@ -69,7 +69,7 @@ pub fn generic<T>() -> usize {
             RET = 1;
             Return()
         }
-    )
+    }
 }
 
 fn main() {

tests/mir-opt/simplify_dead_blocks.rs

@@ -24,7 +24,7 @@ pub unsafe fn assert_nonzero_nonmax(x: u8) -> u8 {
     // CHECK-NEXT: _0 = _1;
     // CHECK-NEXT: return;
     // CHECK-NEXT: }
-    mir!(
+    mir! {
         {
             match x {
                 0 => unreachable,
@@ -48,5 +48,5 @@ pub unsafe fn assert_nonzero_nonmax(x: u8) -> u8 {
             RET = x;
             Return()
         }
-    )
+    }
 }

tests/mir-opt/switch_to_self.rs

@@ -8,7 +8,7 @@ use std::intrinsics::mir::*;
 // EMIT_MIR switch_to_self.test.MatchBranchSimplification.diff
 #[custom_mir(dialect = "runtime", phase = "post-cleanup")]
 pub fn test(x: bool) {
-    mir!(
+    mir! {
         {
             Goto(bb0)
         }
@@ -18,5 +18,5 @@ pub fn test(x: bool) {
         bb1 = {
             match x { false => bb0, _ => bb1 }
         }
-    )
+    }
 }

tests/ui/mir/lint/assignment-overlap.rs

@@ -9,11 +9,11 @@ use core::intrinsics::mir::*;
 
 #[custom_mir(dialect = "runtime", phase = "optimized")]
 pub fn main() {
-    mir!(
+    mir! {
         let a: [u8; 1024];
         {
             a = a;
             Return()
         }
-    )
+    }
 }

tests/ui/mir/lint/call-overlap.rs

@@ -9,7 +9,7 @@ use core::intrinsics::mir::*;
 
 #[custom_mir(dialect = "runtime", phase = "optimized")]
 pub fn main() {
-    mir!(
+    mir! {
         let a: [u8; 1024];
         {
             Call(a = f(Move(a)), ReturnTo(bb1), UnwindUnreachable())
@@ -17,7 +17,7 @@ pub fn main() {
         bb1 = {
             Return()
         }
-    )
+    }
 }
 
 pub fn f<T: Copy>(a: T) -> T { a }

tests/ui/mir/lint/no-storage.rs

@@ -8,7 +8,7 @@ use core::intrinsics::mir::*;
 
 #[custom_mir(dialect = "built")]
 pub fn f(a: bool) {
-    mir!(
+    mir! {
         let b: ();
         {
             match a { true => bb1, _ => bb2 }
@@ -26,5 +26,5 @@ pub fn f(a: bool) {
             StorageDead(b);
             Return()
         }
-    )
+    }
 }

tests/ui/mir/lint/storage-live.rs

@@ -15,14 +15,14 @@ use core::ptr::{addr_of, addr_of_mut};
 
 #[custom_mir(dialect = "built")]
 fn multiple_storage() {
-    mir!(
+    mir! {
         let a: usize;
         {
             StorageLive(a);
             StorageLive(a);
             Return()
         }
-    )
+    }
 }
 
 fn main() {

tests/ui/mir/lint/storage-return.rs

@@ -8,12 +8,12 @@ use core::intrinsics::mir::*;
 
 #[custom_mir(dialect = "built")]
 fn main() {
-    mir!(
+    mir! {
         let a: ();
         {
             StorageLive(a);
             RET = a;
             Return()
         }
-    )
+    }
 }

tests/ui/mir/mir_codegen_ssa.rs

@@ -5,7 +5,7 @@ use std::intrinsics::mir::*;
 
 #[custom_mir(dialect = "runtime", phase = "optimized")]
 pub fn f(a: u32) -> u32 {
-    mir!(
+    mir! {
         let x: u32;
         {
             // Previously code generation failed with ICE "use of .. before def ..." because the
@@ -15,5 +15,5 @@ pub fn f(a: u32) -> u32 {
             RET = x;
             Return()
         }
-    )
+    }
 }

tests/ui/mir/ssa_call_ret.rs

@@ -10,7 +10,7 @@ use core::intrinsics::mir::*;
 
 #[custom_mir(dialect = "runtime", phase = "optimized")]
 pub fn f() -> u32 {
-    mir!(
+    mir! {
         let a: u32;
         {
             Call(a = g(), ReturnTo(bb1), UnwindCleanup(bb2))
@@ -23,7 +23,7 @@ pub fn f() -> u32 {
             RET = a;
             UnwindResume()
         }
-    )
+    }
 }
 
 #[inline(never)]

tests/ui/mir/validate/critical-edge.rs

@@ -12,7 +12,7 @@ use core::intrinsics::mir::*;
 #[custom_mir(dialect = "runtime", phase = "optimized")]
 #[inline(always)]
 pub fn f(a: u32) -> u32 {
-    mir!(
+    mir! {
         {
             match a {
                 0 => bb1,
@@ -27,5 +27,5 @@ pub fn f(a: u32) -> u32 {
             RET = 2;
             Return()
         }
-    )
+    }
 }

tests/ui/mir/validate/noncleanup-cleanup.rs

@@ -9,13 +9,12 @@ use core::intrinsics::mir::*;
 
 #[custom_mir(dialect = "built")]
 pub fn main() {
-    mir!(
+    mir! {
         {
             Call(RET = main(), ReturnTo(block), UnwindCleanup(block))
         }
         block = {
             Return()
         }
-    )
+    }
-
 }

tests/ui/mir/validate/noncleanup-resume.rs

@@ -9,9 +9,9 @@ use core::intrinsics::mir::*;
 
 #[custom_mir(dialect = "built")]
 pub fn main() {
-    mir!(
+    mir! {
         {
             UnwindResume()
         }
-    )
+    }
 }

tests/ui/mir/validate/noncleanup-terminate.rs

@@ -9,9 +9,9 @@ use core::intrinsics::mir::*;
 
 #[custom_mir(dialect = "built")]
 pub fn main() {
-    mir!(
+    mir! {
         {
             UnwindTerminate(ReasonAbi)
         }
-    )
+    }
 }