JIT: Disable implicit tailcalls for throwhelpers (#61006)

src/coreclr/jit/morph.cpp

@@ -7132,15 +7132,11 @@ GenTree* Compiler::fgMorphPotentialTailCall(GenTreeCall* call)
         return nullptr;
     }
 
-    // Heuristic: regular calls to noreturn methods can sometimes be
-    // merged, so if we have multiple such calls, we defer tail calling.
-    //
-    // TODO: re-examine this; now that we're merging before morph we
-    // don't need to worry about interfering with merges.
-    //
-    if (call->IsNoReturn() && (optNoReturnCallCount > 1))
+    if (call->IsNoReturn() && !call->IsTailPrefixedCall())
     {
-        failTailCall("Defer tail calling throw helper; anticipating merge");
+        // Such tail calls always throw an exception and we won't be able to see current
+        // Caller() in the stacktrace.
+        failTailCall("Never returns");
         return nullptr;
     }