8294538: missing is_unloading() check in SharedRuntime::fixup_callers…

…_callsite()

Backport-of: b5efa2afe268e3171f54d8488ef69bf67059bd7f

src/hotspot/share/oops/method.cpp

@@ -1245,15 +1245,6 @@ void Method::restore_unshareable_info(TRAPS) {
   assert(is_method() && is_valid_method(this), "ensure C++ vtable is restored");
 }
 
-address Method::from_compiled_entry_no_trampoline() const {
-  CompiledMethod *code = Atomic::load_acquire(&_code);
-  if (code) {
-    return code->verified_entry_point();
-  } else {
-    return adapter()->get_c2i_entry();
-  }
-}
-
 // The verified_code_entry() must be called when a invoke is resolved
 // on this method.
 

src/hotspot/share/oops/method.hpp

@@ -138,7 +138,6 @@ class Method : public Metadata {
 
   static address make_adapters(const methodHandle& mh, TRAPS);
   address from_compiled_entry() const;
-  address from_compiled_entry_no_trampoline() const;
   address from_interpreted_entry() const;
 
   // access flag

src/hotspot/share/runtime/sharedRuntime.cpp

@@ -1946,8 +1946,6 @@ bool SharedRuntime::should_fixup_call_destination(address destination, address e
 JRT_LEAF(void, SharedRuntime::fixup_callers_callsite(Method* method, address caller_pc))
   Method* moop(method);
 
-  address entry_point = moop->from_compiled_entry_no_trampoline();
-
   // It's possible that deoptimization can occur at a call site which hasn't
   // been resolved yet, in which case this function will be called from
   // an nmethod that has been patched for deopt and we can ignore the
@@ -1958,8 +1956,16 @@ JRT_LEAF(void, SharedRuntime::fixup_callers_callsite(Method* method, address cal
   // "to interpreter" stub in order to load up the Method*. Don't
   // ask me how I know this...
 
+  // Result from nmethod::is_unloading is not stable across safepoints.
+  NoSafepointVerifier nsv;
+
+  CompiledMethod* callee = moop->code();
+  if (callee == NULL) {
+    return;
+  }
+
   CodeBlob* cb = CodeCache::find_blob(caller_pc);
-  if (cb == NULL || !cb->is_compiled() || entry_point == moop->get_c2i_entry()) {
+  if (cb == NULL || !cb->is_compiled() || callee->is_unloading()) {
     return;
   }
 
@@ -2007,6 +2013,7 @@ JRT_LEAF(void, SharedRuntime::fixup_callers_callsite(Method* method, address cal
         return;
       }
       address destination = call->destination();
+      address entry_point = callee->verified_entry_point();
       if (should_fixup_call_destination(destination, entry_point, caller_pc, moop, cb)) {
         call->set_destination_mt_safe(entry_point);
       }