Add UnwindAction::Unreachable

This also makes eval machine's `StackPopUnwind`
redundant so that is replaced.

Author: nbdd0121

src/helpers.rs

@@ -951,7 +951,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         if this.machine.panic_on_unsupported {
             // message is slightly different here to make automated analysis easier
             let error_msg = format!("unsupported Miri functionality: {}", error_msg.as_ref());
-            this.start_panic(error_msg.as_ref(), StackPopUnwind::Skip)?;
+            this.start_panic(error_msg.as_ref(), mir::UnwindAction::Continue)?;
             Ok(())
         } else {
             throw_unsup_format!("{}", error_msg.as_ref());

src/machine.rs

@@ -834,7 +834,7 @@ impl<'mir, 'tcx> Machine<'mir, 'tcx> for MiriMachine<'mir, 'tcx> {
         args: &[OpTy<'tcx, Provenance>],
         dest: &PlaceTy<'tcx, Provenance>,
         ret: Option<mir::BasicBlock>,
-        unwind: StackPopUnwind,
+        unwind: mir::UnwindAction,
     ) -> InterpResult<'tcx, Option<(&'mir mir::Body<'tcx>, ty::Instance<'tcx>)>> {
         ecx.find_mir_or_eval_fn(instance, abi, args, dest, ret, unwind)
     }
@@ -847,7 +847,7 @@ impl<'mir, 'tcx> Machine<'mir, 'tcx> for MiriMachine<'mir, 'tcx> {
         args: &[OpTy<'tcx, Provenance>],
         dest: &PlaceTy<'tcx, Provenance>,
         ret: Option<mir::BasicBlock>,
-        _unwind: StackPopUnwind,
+        _unwind: mir::UnwindAction,
     ) -> InterpResult<'tcx> {
         ecx.call_dlsym(fn_val, abi, args, dest, ret)
     }
@@ -859,7 +859,7 @@ impl<'mir, 'tcx> Machine<'mir, 'tcx> for MiriMachine<'mir, 'tcx> {
         args: &[OpTy<'tcx, Provenance>],
         dest: &PlaceTy<'tcx, Provenance>,
         ret: Option<mir::BasicBlock>,
-        unwind: StackPopUnwind,
+        unwind: mir::UnwindAction,
     ) -> InterpResult<'tcx> {
         ecx.call_intrinsic(instance, args, dest, ret, unwind)
     }

src/shims/foreign_items.rs

@@ -258,7 +258,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         args: &[OpTy<'tcx, Provenance>],
         dest: &PlaceTy<'tcx, Provenance>,
         ret: Option<mir::BasicBlock>,
-        unwind: StackPopUnwind,
+        unwind: mir::UnwindAction,
     ) -> InterpResult<'tcx, Option<(&'mir mir::Body<'tcx>, ty::Instance<'tcx>)>> {
         let this = self.eval_context_mut();
         let link_name = this.item_link_name(def_id);

src/shims/intrinsics/mod.rs

@@ -26,7 +26,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         args: &[OpTy<'tcx, Provenance>],
         dest: &PlaceTy<'tcx, Provenance>,
         ret: Option<mir::BasicBlock>,
-        _unwind: StackPopUnwind,
+        _unwind: mir::UnwindAction,
     ) -> InterpResult<'tcx> {
         let this = self.eval_context_mut();
 

src/shims/mod.rs

@@ -34,7 +34,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         args: &[OpTy<'tcx, Provenance>],
         dest: &PlaceTy<'tcx, Provenance>,
         ret: Option<mir::BasicBlock>,
-        unwind: StackPopUnwind,
+        unwind: mir::UnwindAction,
     ) -> InterpResult<'tcx, Option<(&'mir mir::Body<'tcx>, ty::Instance<'tcx>)>> {
         let this = self.eval_context_mut();
         trace!("eval_fn_call: {:#?}, {:?}", instance, dest);
@@ -70,7 +70,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         align_op: &OpTy<'tcx, Provenance>,
         dest: &PlaceTy<'tcx, Provenance>,
         ret: Option<mir::BasicBlock>,
-        unwind: StackPopUnwind,
+        unwind: mir::UnwindAction,
     ) -> InterpResult<'tcx, bool> {
         let this = self.eval_context_mut();
         let ret = ret.unwrap();

src/shims/panic.rs

@@ -53,7 +53,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         abi: Abi,
         link_name: Symbol,
         args: &[OpTy<'tcx, Provenance>],
-        unwind: StackPopUnwind,
+        unwind: mir::UnwindAction,
     ) -> InterpResult<'tcx> {
         let this = self.eval_context_mut();
 
@@ -106,7 +106,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
             &[data.into()],
             None,
             // Directly return to caller.
-            StackPopCleanup::Goto { ret: Some(ret), unwind: StackPopUnwind::Skip },
+            StackPopCleanup::Goto { ret: Some(ret), unwind: mir::UnwindAction::Continue },
         )?;
 
         // We ourselves will return `0`, eventually (will be overwritten if we catch a panic).
@@ -157,7 +157,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                 &[catch_unwind.data.into(), payload.into()],
                 None,
                 // Directly return to caller of `try`.
-                StackPopCleanup::Goto { ret: Some(catch_unwind.ret), unwind: StackPopUnwind::Skip },
+                StackPopCleanup::Goto { ret: Some(catch_unwind.ret), unwind: mir::UnwindAction::Continue },
             )?;
 
             // We pushed a new stack frame, the engine should not do any jumping now!
@@ -168,7 +168,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     }
 
     /// Start a panic in the interpreter with the given message as payload.
-    fn start_panic(&mut self, msg: &str, unwind: StackPopUnwind) -> InterpResult<'tcx> {
+    fn start_panic(&mut self, msg: &str, unwind: mir::UnwindAction) -> InterpResult<'tcx> {
         let this = self.eval_context_mut();
 
         // First arg: message.
@@ -213,10 +213,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                     None,
                     StackPopCleanup::Goto {
                         ret: None,
-                        unwind: match unwind {
-                            Some(cleanup) => StackPopUnwind::Cleanup(cleanup),
-                            None => StackPopUnwind::Skip,
-                        },
+                        unwind,
                     },
                 )?;
             }
@@ -252,10 +249,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                 // Forward everything else to `panic` lang item.
                 this.start_panic(
                     msg.description(),
-                    match unwind {
-                        Some(cleanup) => StackPopUnwind::Cleanup(cleanup),
-                        None => StackPopUnwind::Skip,
-                    },
+                    unwind,
                 )?;
             }
         }