interpret, miri: uniform treatments of intrinsics/functions with and without return block

2 files changed, 5 insertions, 20 deletions

diff --git a/compiler/rustc_const_eval/src/const_eval/machine.rs b/compiler/rustc_const_eval/src/const_eval/machine.rs
index e9cf5a3d769..6e6fa70107b 100644
--- a/compiler/rustc_const_eval/src/const_eval/machine.rs
+++ b/compiler/rustc_const_eval/src/const_eval/machine.rs
@@ -467,19 +467,6 @@ impl<'mir, 'tcx> interpret::Machine<'mir, 'tcx> for CompileTimeInterpreter<'mir,
         let intrinsic_name = ecx.tcx.item_name(instance.def_id());
 
         // CTFE-specific intrinsics.
-        let Some(ret) = target else {
-            // Handle diverging intrinsics. We can't handle any of them (that are not already
-            // handled above), but check if there is a fallback body.
-            if ecx.tcx.intrinsic(instance.def_id()).unwrap().must_be_overridden {
-                throw_unsup_format!(
-                    "intrinsic `{intrinsic_name}` is not supported at compile-time"
-                );
-            }
-            return Ok(Some(ty::Instance {
-                def: ty::InstanceDef::Item(instance.def_id()),
-                args: instance.args,
-            }));
-        };
         match intrinsic_name {
             sym::ptr_guaranteed_cmp => {
                 let a = ecx.read_scalar(&args[0])?;
@@ -559,7 +546,8 @@ impl<'mir, 'tcx> interpret::Machine<'mir, 'tcx> for CompileTimeInterpreter<'mir,
             }
         }
 
-        ecx.go_to_block(ret);
+        // Intrinsic is done, jump to next block.
+        ecx.return_to_block(target)?;
         Ok(None)
     }
 
diff --git a/compiler/rustc_const_eval/src/interpret/intrinsics.rs b/compiler/rustc_const_eval/src/interpret/intrinsics.rs
index f73293856c7..88ce5a7cbeb 100644
--- a/compiler/rustc_const_eval/src/interpret/intrinsics.rs
+++ b/compiler/rustc_const_eval/src/interpret/intrinsics.rs
@@ -113,10 +113,6 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
     ) -> InterpResult<'tcx, bool> {
         let instance_args = instance.args;
         let intrinsic_name = self.tcx.item_name(instance.def_id());
-        let Some(ret) = ret else {
-            // We don't support any intrinsic without return place.
-            return Ok(false);
-        };
 
         match intrinsic_name {
             sym::caller_location => {
@@ -376,7 +372,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                     };
 
                     M::panic_nounwind(self, &msg)?;
-                    // Skip the `go_to_block` at the end.
+                    // Skip the `return_to_block` at the end (we panicked, we do not return).
                     return Ok(true);
                 }
             }
@@ -437,11 +433,12 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                 self.write_scalar(Scalar::from_target_usize(align.bytes(), self), dest)?;
             }
 
+            // Unsupported intrinsic: skip the return_to_block below.
             _ => return Ok(false),
         }
 
         trace!("{:?}", self.dump_place(&dest.clone().into()));
-        self.go_to_block(ret);
+        self.return_to_block(ret)?;
         Ok(true)
     }