make MIR less verbose

Author: RalfJung

compiler/rustc_middle/src/mir/terminator.rs

@@ -119,6 +119,14 @@ impl UnwindTerminateReason {
         }
     }
 
+    /// A short representation of this used for MIR printing.
+    pub fn as_short_str(self) -> &'static str {
+        match self {
+            UnwindTerminateReason::Abi => "abi",
+            UnwindTerminateReason::InCleanup => "cleanup",
+        }
+    }
+
     pub fn lang_item(self) -> LangItem {
         match self {
             UnwindTerminateReason::Abi => LangItem::PanicCannotUnwind,
@@ -301,13 +309,14 @@ impl<'tcx> Debug for TerminatorKind<'tcx> {
         // `Cleanup` is already included in successors
         let show_unwind = !matches!(self.unwind(), None | Some(UnwindAction::Cleanup(_)));
         let fmt_unwind = |fmt: &mut Formatter<'_>| -> fmt::Result {
+            write!(fmt, "unwind ")?;
             match self.unwind() {
                 // Not needed or included in successors
                 None | Some(UnwindAction::Cleanup(_)) => unreachable!(),
-                Some(UnwindAction::Continue) => write!(fmt, "unwind continue"),
-                Some(UnwindAction::Unreachable) => write!(fmt, "unwind unreachable"),
+                Some(UnwindAction::Continue) => write!(fmt, "continue"),
+                Some(UnwindAction::Unreachable) => write!(fmt, "unreachable"),
                 Some(UnwindAction::Terminate(reason)) => {
-                    write!(fmt, "unwind terminate ({})", reason.as_str())
+                    write!(fmt, "terminate({})", reason.as_short_str())
                 }
             }
         };
@@ -350,7 +359,7 @@ impl<'tcx> TerminatorKind<'tcx> {
             GeneratorDrop => write!(fmt, "generator_drop"),
             UnwindResume => write!(fmt, "resume"),
             UnwindTerminate(reason) => {
-                write!(fmt, "abort(\"{}\")", reason.as_str())
+                write!(fmt, "abort({})", reason.as_short_str())
             }
             Yield { value, resume_arg, .. } => write!(fmt, "{resume_arg:?} = yield({value:?})"),
             Unreachable => write!(fmt, "unreachable"),

tests/mir-opt/asm_unwind_panic_abort.main.AbortUnwindingCalls.after.mir

@@ -9,7 +9,7 @@ fn main() -> () {
     bb0: {
         StorageLive(_1);
         _1 = const ();
-        asm!("", options(MAY_UNWIND)) -> [return: bb1, unwind terminate (panic in a function that cannot unwind)];
+        asm!("", options(MAY_UNWIND)) -> [return: bb1, unwind terminate(abi)];
     }
 
     bb1: {

tests/mir-opt/basic_assignment.main.ElaborateDrops.diff

@@ -47,7 +47,7 @@
 
       bb2 (cleanup): {
           _5 = move _6;
--         drop(_6) -> [return: bb6, unwind terminate (panic in a destructor during cleanup)];
+-         drop(_6) -> [return: bb6, unwind terminate(cleanup)];
 +         goto -> bb6;
       }
 
@@ -71,12 +71,12 @@
       }
 
       bb6 (cleanup): {
--         drop(_5) -> [return: bb7, unwind terminate (panic in a destructor during cleanup)];
+-         drop(_5) -> [return: bb7, unwind terminate(cleanup)];
 +         goto -> bb7;
       }
 
       bb7 (cleanup): {
--         drop(_4) -> [return: bb8, unwind terminate (panic in a destructor during cleanup)];
+-         drop(_4) -> [return: bb8, unwind terminate(cleanup)];
 +         goto -> bb8;
       }
 

tests/mir-opt/basic_assignment.main.SimplifyCfg-initial.after.mir

@@ -51,7 +51,7 @@ fn main() -> () {
 
     bb2 (cleanup): {
         _5 = move _6;
-        drop(_6) -> [return: bb6, unwind terminate (panic in a destructor during cleanup)];
+        drop(_6) -> [return: bb6, unwind terminate(cleanup)];
     }
 
     bb3: {
@@ -73,11 +73,11 @@ fn main() -> () {
     }
 
     bb6 (cleanup): {
-        drop(_5) -> [return: bb7, unwind terminate (panic in a destructor during cleanup)];
+        drop(_5) -> [return: bb7, unwind terminate(cleanup)];
     }
 
     bb7 (cleanup): {
-        drop(_4) -> [return: bb8, unwind terminate (panic in a destructor during cleanup)];
+        drop(_4) -> [return: bb8, unwind terminate(cleanup)];
     }
 
     bb8 (cleanup): {

tests/mir-opt/box_expr.main.ElaborateDrops.before.panic-abort.mir

@@ -54,15 +54,15 @@ fn main() -> () {
     }
 
     bb6 (cleanup): {
-        drop(_7) -> [return: bb7, unwind terminate (panic in a destructor during cleanup)];
+        drop(_7) -> [return: bb7, unwind terminate(cleanup)];
     }
 
     bb7 (cleanup): {
-        drop(_1) -> [return: bb9, unwind terminate (panic in a destructor during cleanup)];
+        drop(_1) -> [return: bb9, unwind terminate(cleanup)];
     }
 
     bb8 (cleanup): {
-        drop(_5) -> [return: bb9, unwind terminate (panic in a destructor during cleanup)];
+        drop(_5) -> [return: bb9, unwind terminate(cleanup)];
     }
 
     bb9 (cleanup): {

tests/mir-opt/box_expr.main.ElaborateDrops.before.panic-unwind.mir

@@ -54,15 +54,15 @@ fn main() -> () {
     }
 
     bb6 (cleanup): {
-        drop(_7) -> [return: bb7, unwind terminate (panic in a destructor during cleanup)];
+        drop(_7) -> [return: bb7, unwind terminate(cleanup)];
     }
 
     bb7 (cleanup): {
-        drop(_1) -> [return: bb9, unwind terminate (panic in a destructor during cleanup)];
+        drop(_1) -> [return: bb9, unwind terminate(cleanup)];
     }
 
     bb8 (cleanup): {
-        drop(_5) -> [return: bb9, unwind terminate (panic in a destructor during cleanup)];
+        drop(_5) -> [return: bb9, unwind terminate(cleanup)];
     }
 
     bb9 (cleanup): {

tests/mir-opt/building/enum_cast.droppy.built.after.mir

@@ -62,7 +62,7 @@ fn droppy() -> () {
     }
 
     bb4 (cleanup): {
-        drop(_2) -> [return: bb5, unwind terminate (panic in a destructor during cleanup)];
+        drop(_2) -> [return: bb5, unwind terminate(cleanup)];
     }
 
     bb5 (cleanup): {

tests/mir-opt/building/uniform_array_move_out.move_out_by_subslice.built.after.mir

@@ -89,15 +89,15 @@ fn move_out_by_subslice() -> () {
     }
 
     bb9 (cleanup): {
-        drop(_1) -> [return: bb12, unwind terminate (panic in a destructor during cleanup)];
+        drop(_1) -> [return: bb12, unwind terminate(cleanup)];
     }
 
     bb10 (cleanup): {
-        drop(_7) -> [return: bb11, unwind terminate (panic in a destructor during cleanup)];
+        drop(_7) -> [return: bb11, unwind terminate(cleanup)];
     }
 
     bb11 (cleanup): {
-        drop(_2) -> [return: bb12, unwind terminate (panic in a destructor during cleanup)];
+        drop(_2) -> [return: bb12, unwind terminate(cleanup)];
     }
 
     bb12 (cleanup): {

tests/mir-opt/building/uniform_array_move_out.move_out_from_end.built.after.mir

@@ -89,15 +89,15 @@ fn move_out_from_end() -> () {
     }
 
     bb9 (cleanup): {
-        drop(_1) -> [return: bb12, unwind terminate (panic in a destructor during cleanup)];
+        drop(_1) -> [return: bb12, unwind terminate(cleanup)];
     }
 
     bb10 (cleanup): {
-        drop(_7) -> [return: bb11, unwind terminate (panic in a destructor during cleanup)];
+        drop(_7) -> [return: bb11, unwind terminate(cleanup)];
     }
 
     bb11 (cleanup): {
-        drop(_2) -> [return: bb12, unwind terminate (panic in a destructor during cleanup)];
+        drop(_2) -> [return: bb12, unwind terminate(cleanup)];
     }
 
     bb12 (cleanup): {

tests/mir-opt/combine_clone_of_primitives.{impl#0}-clone.InstSimplify.panic-unwind.diff

@@ -63,7 +63,7 @@
       }
 
       bb4 (cleanup): {
-          drop(_2) -> [return: bb5, unwind terminate (panic in a destructor during cleanup)];
+          drop(_2) -> [return: bb5, unwind terminate(cleanup)];
       }
 
       bb5 (cleanup): {