8287040: [lworld][lw4] Remove abstract Object class support from HotSpot

Reviewed-by: dsimms

Author: fparain

src/hotspot/cpu/aarch64/templateTable_aarch64.cpp

@@ -3792,9 +3792,6 @@ void TemplateTable::_new() {
   __ cmp(rscratch1, (u1)InstanceKlass::fully_initialized);
   __ br(Assembler::NE, slow_case);
 
-  __ ldrw(rscratch1, Address(r4, Klass::access_flags_offset()));
-  __ tbz(rscratch1, exact_log2(JVM_ACC_ABSTRACT), slow_case);
-
   __ allocate_instance(r4, r0, r3, r1, true, slow_case);
   __ b(done);
 

src/hotspot/cpu/x86/templateTable_x86.cpp

@@ -4308,10 +4308,6 @@ void TemplateTable::_new() {
   __ cmpb(Address(rcx, InstanceKlass::init_state_offset()), InstanceKlass::fully_initialized);
   __ jcc(Assembler::notEqual, slow_case);
 
-  __ movl(rdx, Address(rcx, Klass::access_flags_offset()));
-  __ testl(rdx, JVM_ACC_ABSTRACT);
-  __ jcc(Assembler::notZero, slow_case);
-
   __ allocate_instance(rcx, rax, rdx, rbx, true, slow_case);
   __ jmp(done);
 

src/hotspot/share/c1/c1_GraphBuilder.cpp

@@ -2568,11 +2568,7 @@ void GraphBuilder::new_instance(int klass_index) {
   bool will_link;
   ciKlass* klass = stream()->get_klass(will_link);
   assert(klass->is_instance_klass(), "must be an instance klass");
-  ciKlass* ik = klass;
-  if (ik == compilation()->env()->Object_klass() && compilation()->env()->Object_klass()->is_abstract()) {
-    ik = compilation()->env()->Identity_klass();
-  }
-  NewInstance* new_instance = new NewInstance(ik->as_instance_klass(), state_before, stream()->is_unresolved_klass());
+  NewInstance* new_instance = new NewInstance(klass->as_instance_klass(), state_before, stream()->is_unresolved_klass());
   _memory->new_instance(new_instance);
   apush(append_split(new_instance));
 }

src/hotspot/share/cds/classListParser.cpp

@@ -469,7 +469,7 @@ InstanceKlass* ClassListParser::load_class_from_source(Symbol* class_name, TRAPS
   InstanceKlass* k = UnregisteredClasses::load_class(class_name, _source, CHECK_NULL);
   const int actual_num_interfaces = k->local_interfaces()->length();
   const int specified_num_interfaces = _interfaces->length(); // specified in classlist
-  int expected_num_interfaces = actual_num_interfaces, i;
+  int expected_num_interfaces = actual_num_interfaces;
 
   if (specified_num_interfaces != expected_num_interfaces) {
     print_specified_interfaces();

src/hotspot/share/ci/ciTypeFlow.cpp

@@ -841,11 +841,6 @@ void ciTypeFlow::StateVector::do_multianewarray(ciBytecodeStream* str) {
 void ciTypeFlow::StateVector::do_new(ciBytecodeStream* str) {
   bool will_link;
   ciKlass* klass = str->get_klass(will_link);
-
-  if (klass == outer()->env()->Object_klass() && outer()->env()->Object_klass()->is_abstract()) {
-    klass = outer()->env()->Identity_klass();
-  }
-
   if (!will_link || str->is_unresolved_klass() || klass->is_inlinetype()) {
     trap(str, klass, str->get_klass_index());
   } else {

src/hotspot/share/classfile/vmClassMacros.hpp

@@ -184,8 +184,6 @@
   do_klass(vector_VectorMask_klass,                     jdk_internal_vm_vector_VectorMask                     ) \
   do_klass(vector_VectorShuffle_klass,                  jdk_internal_vm_vector_VectorShuffle                  ) \
                                                                                                                 \
-  do_klass(Identity_klass,                              java_lang_Identity                                    ) \
-                                                                                                                \
   /*end*/
 
 #endif // SHARE_CLASSFILE_VMCLASSMACROS_HPP

src/hotspot/share/classfile/vmSymbols.hpp

@@ -143,7 +143,6 @@
   template(java_util_Iterator,                        "java/util/Iterator")                       \
   template(java_lang_Record,                          "java/lang/Record")                         \
   template(sun_instrument_InstrumentationImpl,        "sun/instrument/InstrumentationImpl")       \
-  template(java_lang_Identity,                        "java/lang/Identity")                       \
   template(sun_invoke_util_ValueConversions,          "sun/invoke/util/ValueConversions")         \
                                                                                                   \
   template(jdk_internal_loader_NativeLibraries,       "jdk/internal/loader/NativeLibraries")      \

src/hotspot/share/interpreter/interpreterRuntime.cpp

@@ -225,14 +225,6 @@ JRT_ENTRY(void, InterpreterRuntime::_new(JavaThread* current, ConstantPool* pool
   Klass* k = pool->klass_at(index, CHECK);
   InstanceKlass* klass = InstanceKlass::cast(k);
 
-  if (klass->is_abstract()) {
-    if (klass == vmClasses::Object_klass()) {
-      klass = vmClasses::Identity_klass();
-    } else {
-      THROW(vmSymbols::java_lang_InstantiationError());
-    }
-  }
-
   if (klass->is_inline_klass()) {
     THROW(vmSymbols::java_lang_InstantiationError());
   }

src/hotspot/share/memory/universe.cpp

@@ -419,12 +419,7 @@ void Universe::genesis(TRAPS) {
     int i = 0;
     while (i < size) {
         // Allocate dummy in old generation
-      oop dummy;
-      if(vmClasses::Object_klass()->is_abstract()) {
-        dummy = vmClasses::Identity_klass()->allocate_instance(CHECK);
-      } else {
-        dummy = vmClasses::Object_klass()->allocate_instance(CHECK);
-      }
+      oop dummy = vmClasses::Object_klass()->allocate_instance(CHECK);
       dummy_array->obj_at_put(i++, dummy);
     }
     {

src/hotspot/share/opto/library_call.cpp

@@ -3001,21 +3001,6 @@ bool LibraryCallKit::inline_unsafe_allocate() {
   kls = null_check(kls);
   if (stopped())  return true;  // argument was like int.class
 
-  bool object_check = C->env()->Object_klass()->is_abstract();
-
-  IdealKit ideal(this);
-#define __ ideal.
-  IdealVariable result(ideal); __ declarations_done();
-
-  if (object_check) {
-    __ if_then(kls, BoolTest::eq, makecon(TypeKlassPtr::make(C->env()->Object_klass())));
-    sync_kit(ideal);
-    Node* obj = new_instance(makecon(TypeKlassPtr::make(C->env()->Identity_klass())));
-    ideal.sync_kit(this);
-    ideal.set(result, obj);
-    __ else_();
-    sync_kit(ideal);
-  }
   Node* test = NULL;
   if (LibraryCallKit::klass_needs_init_guard(kls)) {
     // Note:  The argument might still be an illegal value like
@@ -3036,15 +3021,7 @@ bool LibraryCallKit::inline_unsafe_allocate() {
   } else {
     obj = new_instance(kls, test);
   }
-  if (object_check) {
-    ideal.sync_kit(this);
-    ideal.set(result, obj);
-    __ end_if();
-    final_sync(ideal);
-    obj = ideal.value(result);
-  }
   set_result(obj);
-#undef __
   return true;
 }
 

src/hotspot/share/opto/parseHelper.cpp

@@ -286,10 +286,6 @@ void Parse::do_new() {
   assert(will_link, "_new: typeflow responsibility");
   assert(!klass->is_inlinetype(), "unexpected inline type");
 
-  if (klass == C->env()->Object_klass() && C->env()->Object_klass()->is_abstract()) {
-    klass = C->env()->Identity_klass();
-  }
-
   // Should throw an InstantiationError?
   if (klass->is_abstract() || klass->is_interface() ||
       klass->name() == ciSymbols::java_lang_Class() ||

src/hotspot/share/prims/jni.cpp

@@ -999,11 +999,7 @@ JNI_ENTRY(jobject, jni_NewObjectA(JNIEnv *env, jclass clazz, jmethodID methodID,
   }
 
   if (!k->is_inline_klass()) {
-    Klass* ik = k;
-    if (ik == vmClasses::Object_klass() && vmClasses::Object_klass()->is_abstract()) {
-      ik = vmClasses::Identity_klass();
-    }
-    instanceOop i = InstanceKlass::allocate_instance(k->java_mirror(), CHECK_NULL);
+    instanceOop i = InstanceKlass::allocate_instance(clazzoop, CHECK_NULL);
     obj = JNIHandles::make_local(THREAD, i);
     JavaValue jvalue(T_VOID);
     JNI_ArgumentPusherArray ap(methodID, args);
@@ -1035,11 +1031,7 @@ JNI_ENTRY(jobject, jni_NewObjectV(JNIEnv *env, jclass clazz, jmethodID methodID,
   }
 
   if (!k->is_inline_klass()) {
-    Klass* ik = k;
-    if (ik == vmClasses::Object_klass() && vmClasses::Object_klass()->is_abstract()) {
-      ik = vmClasses::Identity_klass();
-    }
-    instanceOop i = InstanceKlass::allocate_instance(ik->java_mirror(), CHECK_NULL);
+    instanceOop i = InstanceKlass::allocate_instance(clazzoop, CHECK_NULL);
     obj = JNIHandles::make_local(THREAD, i);
     JavaValue jvalue(T_VOID);
     JNI_ArgumentPusherVaArg ap(methodID, args);
@@ -1071,11 +1063,7 @@ JNI_ENTRY(jobject, jni_NewObject(JNIEnv *env, jclass clazz, jmethodID methodID,
   }
 
   if (!k->is_inline_klass()) {
-     Klass* ik = k;
-    if (ik == vmClasses::Object_klass() && vmClasses::Object_klass()->is_abstract()) {
-      ik = vmClasses::Identity_klass();
-    }
-    instanceOop i = InstanceKlass::allocate_instance(ik->java_mirror(), CHECK_NULL);
+    instanceOop i = InstanceKlass::allocate_instance(clazzoop, CHECK_NULL);
     obj = JNIHandles::make_local(THREAD, i);
     va_list args;
     va_start(args, methodID);

src/hotspot/share/prims/unsafe.cpp

@@ -463,13 +463,8 @@ UNSAFE_LEAF(void, Unsafe_FullFence(JNIEnv *env, jobject unsafe)) {
 ////// Allocation requests
 
 UNSAFE_ENTRY(jobject, Unsafe_AllocateInstance(JNIEnv *env, jobject unsafe, jclass cls)) {
-  oop mirror = JNIHandles::resolve_non_null(cls);
-  InstanceKlass* k = InstanceKlass::cast(java_lang_Class::as_Klass(mirror));
-  if (k == vmClasses::Object_klass() && vmClasses::Object_klass()->is_abstract()) {
-    k = vmClasses::Identity_klass();
-  }
   JvmtiVMObjectAllocEventCollector oam;
-  instanceOop i = InstanceKlass::allocate_instance(k->java_mirror(), CHECK_NULL);
+  instanceOop i = InstanceKlass::allocate_instance(JNIHandles::resolve_non_null(cls), CHECK_NULL);
   return JNIHandles::make_local(THREAD, i);
 } UNSAFE_END
 

src/hotspot/share/runtime/reflection.cpp

@@ -1201,11 +1201,7 @@ oop Reflection::invoke_constructor(oop constructor_mirror, objArrayHandle args,
 
   // main branch of code creates a non-inline object:
   assert(!klass->is_inline_klass(), "classic constructors are only for non-inline classes");
-  InstanceKlass* ik = klass;
-  if (klass == vmClasses::Object_klass() && vmClasses::Object_klass()->is_abstract()) {
-    ik = vmClasses::Identity_klass();
-  }
-  Handle receiver = ik->allocate_instance_handle(CHECK_NULL);
+  Handle receiver = klass->allocate_instance_handle(CHECK_NULL);
 
   // Ignore result from call and return receiver
   invoke(klass, method, receiver, override, ptypes, T_VOID, args, false, CHECK_NULL);

src/java.base/share/classes/java/lang/Identity.java

@@ -533,6 +533,6 @@ long checkFromIndexSize(long fromIndex, long size, long length) {
      * @since 17
      */
     public static Object newIdentity() {
-        return new Identity();
+        return new Object() {};
     }
 }

src/java.base/share/classes/java/util/Objects.java

@@ -35,8 +35,8 @@
 
 public class TestStripMiningDropsSafepoint {
     public static void main(String[] args) {
-        TestFramework.runWithFlags("-XX:CompileCommand=inline,java.util.Objects::newIdentity", "-XX:+UseCountedLoopSafepoints", "-XX:LoopStripMiningIter=1000", "-XX:LoopMaxUnroll=1", "-XX:-RangeCheckElimination");
-        TestFramework.runWithFlags("-XX:CompileCommand=inline,java.util.Objects::newIdentity", "-XX:+UseCountedLoopSafepoints", "-XX:LoopStripMiningIter=1000", "-XX:LoopMaxUnroll=1", "-XX:-RangeCheckElimination", "-XX:-PartialPeelLoop");
+        TestFramework.runWithFlags("-XX:+UseCountedLoopSafepoints", "-XX:LoopStripMiningIter=1000", "-XX:LoopMaxUnroll=1", "-XX:-RangeCheckElimination");
+        TestFramework.runWithFlags("-XX:+UseCountedLoopSafepoints", "-XX:LoopStripMiningIter=1000", "-XX:LoopMaxUnroll=1", "-XX:-RangeCheckElimination", "-XX:-PartialPeelLoop");
     }
 
     @Test

test/hotspot/jtreg/compiler/c2/irTests/TestStripMiningDropsSafepoint.java

@@ -8,7 +8,7 @@ jit.t.t058.k
 jit.t.t058.k
 o instanceof k: true
 Voodoo 3
-java.lang.Identity
+java.lang.Object
 
 Here come the instance variables of ko:
 39.0

test/hotspot/jtreg/vmTestbase/jit/t/t058/t058.gold

@@ -8,7 +8,7 @@ jit.t.t062.t062
 jit.t.t062.t062
 o instanceof t062: true
 Voodoo 3
-java.lang.Identity
+java.lang.Object
 
 Here come the instance variables of ko:
 39.0

test/hotspot/jtreg/vmTestbase/jit/t/t062/t062.gold

@@ -34,11 +34,11 @@ public class EqualsHashCodeContract
 {
     public static void main(String args[]) throws Exception {
 
-        java.security.Identity i1=new MyIdentity("identity",
+        Identity i1=new MyIdentity("identity",
                                    new MyIdentityScope("IdentityScope"));
-        java.security.Identity i2=new MyIdentity("identity",
+        Identity i2=new MyIdentity("identity",
                                    new MyIdentityScope("IdentityScope"));
-        java.security.Identity i3=new MyIdentity("identity",
+        Identity i3=new MyIdentity("identity",
                                    new MyIdentityScope(""));
 
         PublicKey pk1=new MyPublicKey();
@@ -66,7 +66,7 @@ public static void main(String args[]) throws Exception {
     }
 }
 
-class MyIdentity extends java.security.Identity {
+class MyIdentity extends Identity {
     public MyIdentity(String name, IdentityScope is) throws KeyManagementException {
         super(name, is);
     }
@@ -124,18 +124,18 @@ public int size() {
         return 0;
     }
 
-    public java.security.Identity getIdentity(String name) {
+    public Identity getIdentity(String name) {
         return null;
     }
 
-    public java.security.Identity getIdentity(PublicKey key) {
+    public Identity getIdentity(PublicKey key) {
         return null;
     }
 
-    public void addIdentity(java.security.Identity identity)  {
+    public void addIdentity(Identity identity)  {
     }
 
-    public void removeIdentity(java.security.Identity identity)  {
+    public void removeIdentity(Identity identity)  {
     }
 
     public java.util.Enumeration identities() {