8304693: Remove -XX:-UseVtableBasedCHA

Reviewed-by: kvn, coleenp, dholmes

src/hotspot/share/ci/ciMethod.cpp

@@ -718,17 +718,10 @@ ciMethod* ciMethod::find_monomorphic_target(ciInstanceKlass* caller,
   {
     MutexLocker locker(Compile_lock);
     InstanceKlass* context = actual_recv->get_instanceKlass();
-    if (UseVtableBasedCHA) {
+    target = methodHandle(THREAD, Dependencies::find_unique_concrete_method(context,
-      target = methodHandle(THREAD, Dependencies::find_unique_concrete_method(context,
+                                                                            root_m->get_Method(),
-                                                                              root_m->get_Method(),
+                                                                            callee_holder->get_Klass(),
-                                                                              callee_holder->get_Klass(),
+                                                                            this->get_Method()));
-                                                                              this->get_Method()));
-    } else {
-      if (root_m->is_abstract()) {
-        return nullptr; // not supported
-      }
-      target = methodHandle(THREAD, Dependencies::find_unique_concrete_method(context, root_m->get_Method()));
-    }
     assert(target() == nullptr || !target()->is_abstract(), "not allowed");
     // %%% Should upgrade this ciMethod API to look for 1 or 2 concrete methods.
   }

src/hotspot/share/code/dependencies.cpp

@@ -113,11 +113,7 @@ void Dependencies::assert_unique_concrete_method(ciKlass* ctxk, ciMethod* uniqm)
 void Dependencies::assert_unique_concrete_method(ciKlass* ctxk, ciMethod* uniqm, ciKlass* resolved_klass, ciMethod* resolved_method) {
   check_ctxk(ctxk);
   check_unique_method(ctxk, uniqm);
-  if (UseVtableBasedCHA) {
+  assert_common_4(unique_concrete_method_4, ctxk, uniqm, resolved_klass, resolved_method);
-    assert_common_4(unique_concrete_method_4, ctxk, uniqm, resolved_klass, resolved_method);
-  } else {
-    assert_common_2(unique_concrete_method_2, ctxk, uniqm);
-  }
 }
 
 void Dependencies::assert_unique_implementor(ciInstanceKlass* ctxk, ciInstanceKlass* uniqk) {
@@ -1474,7 +1470,6 @@ class LinkedConcreteMethodFinder : public AbstractClassHierarchyWalker {
   // Optionally, a method which was previously determined as a unique target (uniqm) is added as a participant
   // to enable dependency spot-checking and speed up the search.
   LinkedConcreteMethodFinder(InstanceKlass* resolved_klass, Method* resolved_method, Method* uniqm = nullptr) : AbstractClassHierarchyWalker(nullptr) {
-    assert(UseVtableBasedCHA, "required");
     assert(resolved_klass->is_linked(), "required");
     assert(resolved_method->method_holder()->is_linked(), "required");
     assert(!resolved_method->can_be_statically_bound(), "no vtable index available");
@@ -1948,7 +1943,6 @@ Klass* Dependencies::check_unique_concrete_method(InstanceKlass* ctxk,
                                                   Klass* resolved_klass,
                                                   Method* resolved_method,
                                                   KlassDepChange* changes) {
-  assert(UseVtableBasedCHA, "required");
   assert(!ctxk->is_interface() || ctxk == resolved_klass, "sanity");
   assert(!resolved_method->can_be_statically_bound() || resolved_method == uniqm, "sanity");
   assert(resolved_klass->is_subtype_of(resolved_method->method_holder()), "sanity");
@@ -2129,7 +2123,7 @@ Klass* Dependencies::DepStream::check_klass_dependency(KlassDepChange* changes)
   Dependencies::check_valid_dependency_type(type());
 
   if (changes != nullptr) {
-    if (UseVtableBasedCHA && changes->is_klass_init_change()) {
+    if (changes->is_klass_init_change()) {
       return check_klass_init_dependency(changes->as_klass_init_change());
     } else {
       return check_new_klass_dependency(changes->as_new_klass_change());

src/hotspot/share/oops/instanceKlass.cpp

@@ -929,7 +929,7 @@ bool InstanceKlass::link_class_impl(TRAPS) {
       // In case itable verification is ever added.
       // itable().verify(tty, true);
 #endif
-      if (UseVtableBasedCHA && Universe::is_fully_initialized()) {
+      if (Universe::is_fully_initialized()) {
         DeoptimizationScope deopt_scope;
         {
           // Now mark all code that assumes the class is not linked.
@@ -1264,7 +1264,7 @@ void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS)
 
 // Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock
 // is grabbed, to ensure that the compiler is not using the class hierarchy.
-void InstanceKlass::add_to_hierarchy_impl(JavaThread* current) {
+void InstanceKlass::add_to_hierarchy(JavaThread* current) {
   assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint");
 
   DeoptimizationScope deopt_scope;
@@ -1290,23 +1290,6 @@ void InstanceKlass::add_to_hierarchy_impl(JavaThread* current) {
   deopt_scope.deoptimize_marked();
 }
 
-void InstanceKlass::add_to_hierarchy(JavaThread* current) {
-
-  if (UseVtableBasedCHA || !Universe::is_fully_initialized()) {
-    add_to_hierarchy_impl(current);
-  } else {
-    // In case we are not using CHA based vtables we need to make sure the loaded
-    // deopt is completed before anyone links this class.
-    // Linking is done with init_lock held, by loading and deopting with it
-    // held we make sure the deopt is completed before linking.
-    Handle h_init_lock(current, init_lock());
-    ObjectLocker ol(h_init_lock, current);
-    add_to_hierarchy_impl(current);
-
-    // This doesn't need a notify because the wait is only on the class initialization path.
-  }
-}
-
 
 InstanceKlass* InstanceKlass::implementor() const {
   InstanceKlass* volatile* ik = adr_implementor();

src/hotspot/share/oops/instanceKlass.hpp

@@ -828,9 +828,6 @@ public:
   void set_jni_ids(JNIid* ids)                   { _jni_ids = ids; }
   JNIid* jni_id_for(int offset);
 
- private:
-  void add_to_hierarchy_impl(JavaThread* current);
-
  public:
   // maintenance of deoptimization dependencies
   inline DependencyContext dependencies();

src/hotspot/share/runtime/arguments.cpp

@@ -522,6 +522,7 @@ static SpecialFlag const special_jvm_flags[] = {
 #endif // X86
 
   { "HeapFirstMaximumCompactionCount", JDK_Version::undefined(), JDK_Version::jdk(24), JDK_Version::jdk(25) },
+  { "UseVtableBasedCHA",               JDK_Version::undefined(), JDK_Version::jdk(24), JDK_Version::jdk(25) },
 #ifdef ASSERT
   { "DummyObsoleteTestFlag",        JDK_Version::undefined(), JDK_Version::jdk(18), JDK_Version::undefined() },
 #endif

src/hotspot/share/runtime/globals.hpp

@@ -968,9 +968,6 @@ const int ObjectAlignmentInBytes = 8;
   develop(bool, UseCHA, true,                                               \
           "Enable CHA")                                                     \
                                                                             \
-  product(bool, UseVtableBasedCHA, true,  DIAGNOSTIC,                       \
-          "Use vtable information during CHA")                              \
-                                                                            \
   product(bool, UseTypeProfile, true,                                       \
           "Check interpreter profile for historically monomorphic calls")   \
                                                                             \

test/hotspot/jtreg/compiler/cha/AbstractRootMethod.java

@@ -23,7 +23,7 @@
 
 /*
  * @test
- * @requires !vm.graal.enabled & vm.opt.final.UseVtableBasedCHA == true
+ * @requires !vm.graal.enabled
  * @modules java.base/jdk.internal.org.objectweb.asm
  *          java.base/jdk.internal.misc
  *          java.base/jdk.internal.vm.annotation

test/hotspot/jtreg/compiler/cha/DefaultRootMethod.java

@@ -23,7 +23,7 @@
 
 /*
  * @test
- * @requires !vm.graal.enabled & vm.opt.final.UseVtableBasedCHA == true
+ * @requires !vm.graal.enabled
  * @modules java.base/jdk.internal.org.objectweb.asm
  *          java.base/jdk.internal.misc
  *          java.base/jdk.internal.vm.annotation

test/hotspot/jtreg/compiler/cha/StrengthReduceInterfaceCall.java

@@ -23,7 +23,7 @@
 
 /*
  * @test
- * @requires !vm.graal.enabled & vm.opt.final.UseVtableBasedCHA == true
+ * @requires !vm.graal.enabled
  * @modules java.base/jdk.internal.org.objectweb.asm
  *          java.base/jdk.internal.misc
  *          java.base/jdk.internal.vm.annotation

test/hotspot/jtreg/runtime/InvocationTests/invocationOldCHATests.java

@@ -1,117 +0,0 @@
-/*
- * Copyright (c) 2019, 2023, Oracle and/or its affiliates. All rights reserved.
- * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
- *
- * This code is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 only, as
- * published by the Free Software Foundation.
- *
- * This code is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
- * version 2 for more details (a copy is included in the LICENSE file that
- * accompanied this code).
- *
- * You should have received a copy of the GNU General Public License version
- * 2 along with this work; if not, write to the Free Software Foundation,
- * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
- *
- * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
- * or visit www.oracle.com if you need additional information or have any
- * questions.
- *
- */
-
-/*
- * @test id=special
- * @summary Run invocation tests with old CHA (-XX:-UseVtableBasedCHA)
- * @requires vm.flagless
- * @library /test/lib
- * @modules java.base/jdk.internal.org.objectweb.asm
- *          java.base/jdk.internal.misc
- * @compile invokespecial/Checker.java invokespecial/ClassGenerator.java invokespecial/Generator.java
- *
- * @run driver/timeout=1800 invocationOldCHATests special
- */
-
-/*
- * @test id=virtual
- * @summary Run invocation tests with old CHA (-XX:-UseVtableBasedCHA)
- * @requires vm.flagless
- * @library /test/lib
- * @modules java.base/jdk.internal.org.objectweb.asm
- *          java.base/jdk.internal.misc
- * @compile invokevirtual/Checker.java invokevirtual/ClassGenerator.java invokevirtual/Generator.java
- *
- * @run driver/timeout=1800 invocationOldCHATests virtual
- */
-
-/*
- * @test id=interface
- * @summary Run invocation tests with old CHA (-XX:-UseVtableBasedCHA)
- * @requires vm.flagless
- * @library /test/lib
- * @modules java.base/jdk.internal.org.objectweb.asm
- *          java.base/jdk.internal.misc
- * @compile invokeinterface/Checker.java invokeinterface/ClassGenerator.java invokeinterface/Generator.java
- *
- * @run driver/timeout=1800 invocationOldCHATests interface
- */
-
-import jdk.test.lib.process.ProcessTools;
-import jdk.test.lib.process.OutputAnalyzer;
-import jdk.test.lib.compiler.InMemoryJavaCompiler;
-
-public class invocationOldCHATests {
-
-    public static void runTest(String whichTests, String classFileVersion) throws Throwable {
-        System.out.println("\nOld CHA invocation tests, Tests: " + whichTests +
-                           ", class file version: " + classFileVersion);
-        ProcessBuilder pb = ProcessTools.createLimitedTestJavaProcessBuilder("-Xmx128M",
-            "-Xcomp", "-XX:+UnlockDiagnosticVMOptions", "-XX:-UseVtableBasedCHA",
-            "--add-exports", "java.base/jdk.internal.org.objectweb.asm=ALL-UNNAMED",
-            whichTests, "--classfile_version=" + classFileVersion);
-        OutputAnalyzer output = new OutputAnalyzer(pb.start());
-        try {
-            output.shouldContain("EXECUTION STATUS: PASSED");
-            output.shouldHaveExitValue(0);
-        } catch (Throwable e) {
-            System.out.println(
-                "\nNote that an entry such as 'B.m/C.m' in the failure chart means that" +
-                " the test case failed because method B.m was invoked but the test " +
-                "expected method C.m to be invoked. Similarly, a result such as 'AME/C.m'" +
-                " means that an AbstractMethodError exception was thrown but the test" +
-                " case expected method C.m to be invoked.");
-            System.out.println(
-                "\nAlso note that passing --dump to invoke*.Generator will" +
-                " dump the generated classes (for debugging purposes).\n");
-
-            throw e;
-        }
-    }
-
-    public static void main(String args[]) throws Throwable {
-        if (args.length < 1) {
-            throw new IllegalArgumentException("Should provide the test name");
-        }
-        String testName = args[0];
-
-        // Get current major class file version and test with it.
-        byte klassbuf[] = InMemoryJavaCompiler.compile("blah", "public class blah { }");
-        int major_version = klassbuf[6] << 8 | klassbuf[7];
-
-        switch (testName) {
-            case "special":
-                runTest("invokespecial.Generator", String.valueOf(major_version));
-                break;
-            case "virtual":
-                runTest("invokevirtual.Generator", String.valueOf(major_version));
-                break;
-            case "interface":
-                runTest("invokeinterface.Generator", String.valueOf(major_version));
-                break;
-            default:
-                throw new IllegalArgumentException("Unknown test name: " + testName);
-        }
-    }
-}

test/jtreg-ext/requires/VMProps.java

@@ -386,7 +386,6 @@ public class VMProps implements Callable<Map<String, String>> {
         vmOptFinalFlag(map, "EliminateAllocations");
         vmOptFinalFlag(map, "UseCompressedOops");
         vmOptFinalFlag(map, "UseVectorizedMismatchIntrinsic");
-        vmOptFinalFlag(map, "UseVtableBasedCHA");
         vmOptFinalFlag(map, "ZGenerational");
     }