7000578: CMS: assert(SafepointSynchronize::is_at_safepoint()) failed: Else races are possible

Summary: Weakened assert in onj_is_alive() to allow its use at initialization time when is_at_safepoint() normally reports false; added some related asserts to check order of is_init_completed() after Universe::is_fully_initialized().
Reviewed-by: jcoomes

src/share/vm/gc_implementation/concurrentMarkSweep/compactibleFreeListSpace.cpp

@@ -1093,8 +1093,9 @@ bool CompactibleFreeListSpace::block_is_obj(const HeapWord* p) const {
 // perm_gen_verify_bit_map where we store the "deadness" information if
 // we did not sweep the perm gen in the most recent previous GC cycle.
 bool CompactibleFreeListSpace::obj_is_alive(const HeapWord* p) const {
+  assert(SafepointSynchronize::is_at_safepoint() || !is_init_completed(),
+         "Else races are possible");
   assert(block_is_obj(p), "The address should point to an object");
-  assert(SafepointSynchronize::is_at_safepoint(), "Else races are possible");
 
   // If we're sweeping, we use object liveness information from the main bit map
   // for both perm gen and old gen.

src/share/vm/includeDB_core

@@ -4454,6 +4454,7 @@ universe.cpp                            genRemSet.hpp
 universe.cpp                            generation.hpp
 universe.cpp                            handles.inline.hpp
 universe.cpp                            hashtable.inline.hpp
+universe.cpp                            init.hpp
 universe.cpp                            instanceKlass.hpp
 universe.cpp                            instanceKlassKlass.hpp
 universe.cpp                            instanceRefKlass.hpp

src/share/vm/memory/universe.cpp

@@ -945,6 +945,7 @@ void universe2_init() {
 extern void initialize_converter_functions();
 
 bool universe_post_init() {
+  assert(!is_init_completed(), "Error: initialization not yet completed!");
   Universe::_fully_initialized = true;
   EXCEPTION_MARK;
   { ResourceMark rm;

src/share/vm/runtime/init.cpp

@@ -160,5 +160,6 @@ bool is_init_completed() {
 
 
 void set_init_completed() {
+  assert(Universe::is_fully_initialized(), "Should have completed initialization");
   _init_completed = true;
 }