8038240: new WB API to get nmethod

Reviewed-by: morris, kvn

src/share/vm/prims/whitebox.cpp

 /*
- * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2014, 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
@@ -510,6 +510,44 @@ WB_ENTRY(jstring, WB_GetCPUFeatures(JNIEnv* env, jobject o))
   return features_string;
 WB_END
 
+
+WB_ENTRY(jobjectArray, WB_GetNMethod(JNIEnv* env, jobject o, jobject method, jboolean is_osr))
+  ResourceMark rm(THREAD);
+  jmethodID jmid = reflected_method_to_jmid(thread, env, method);
+  CHECK_JNI_EXCEPTION_(env, NULL);
+  methodHandle mh(THREAD, Method::checked_resolve_jmethod_id(jmid));
+  nmethod* code = is_osr ? mh->lookup_osr_nmethod_for(InvocationEntryBci, CompLevel_none, false) : mh->code();
+  jobjectArray result = NULL;
+  if (code == NULL) {
+    return result;
+  }
+  int insts_size = code->insts_size();
+
+  ThreadToNativeFromVM ttn(thread);
+  jclass clazz = env->FindClass(vmSymbols::java_lang_Object()->as_C_string());
+  CHECK_JNI_EXCEPTION_(env, NULL);
+  result = env->NewObjectArray(2, clazz, NULL);
+  if (result == NULL) {
+    return result;
+  }
+
+  clazz = env->FindClass(vmSymbols::java_lang_Integer()->as_C_string());
+  CHECK_JNI_EXCEPTION_(env, NULL);
+  jmethodID constructor = env->GetMethodID(clazz, vmSymbols::object_initializer_name()->as_C_string(), vmSymbols::int_void_signature()->as_C_string());
+  CHECK_JNI_EXCEPTION_(env, NULL);
+  jobject obj = env->NewObject(clazz, constructor, code->comp_level());
+  CHECK_JNI_EXCEPTION_(env, NULL);
+  env->SetObjectArrayElement(result, 0, obj);
+
+  jbyteArray insts = env->NewByteArray(insts_size);
+  CHECK_JNI_EXCEPTION_(env, NULL);
+  env->SetByteArrayRegion(insts, 0, insts_size, (jbyte*) code->insts_begin());
+  env->SetObjectArrayElement(result, 1, insts);
+
+  return result;
+WB_END
+
+
 //Some convenience methods to deal with objects from java
 int WhiteBox::offset_for_field(const char* field_name, oop object,
     Symbol* signature_symbol) {
@@ -622,6 +660,8 @@ static JNINativeMethod methods[] = {
   {CC"fullGC",   CC"()V",                             (void*)&WB_FullGC },
   {CC"readReservedMemory", CC"()V",                   (void*)&WB_ReadReservedMemory },
   {CC"getCPUFeatures",     CC"()Ljava/lang/String;",  (void*)&WB_GetCPUFeatures     },
+  {CC"getNMethod",         CC"(Ljava/lang/reflect/Executable;Z)[Ljava/lang/Object;",
+                                                      (void*)&WB_GetNMethod         },
 };
 
 #undef CC

src/share/vm/prims/whitebox.hpp

 /*
- * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2014, 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
@@ -40,7 +40,6 @@
   do {                                                                 \
     JavaThread* THREAD = JavaThread::thread_from_jni_environment(env); \
     if (HAS_PENDING_EXCEPTION) {                                       \
-      CLEAR_PENDING_EXCEPTION;                                         \
       return(value);                                                   \
     }                                                                  \
   } while (0)
@@ -49,7 +48,6 @@
   do {                                                                 \
     JavaThread* THREAD = JavaThread::thread_from_jni_environment(env); \
     if (HAS_PENDING_EXCEPTION) {                                       \
-      CLEAR_PENDING_EXCEPTION;                                         \
       return;                                                          \
     }                                                                  \
   } while (0)

test/compiler/whitebox/CompilerWhiteBoxTest.java

@@ -24,6 +24,7 @@
 import com.sun.management.HotSpotDiagnosticMXBean;
 import com.sun.management.VMOption;
 import sun.hotspot.WhiteBox;
+import sun.hotspot.code.NMethod;
 import sun.management.ManagementFactoryHelper;
 
 import java.lang.reflect.Constructor;
@@ -255,7 +256,8 @@ public abstract class CompilerWhiteBoxTest {
     }
 
     protected final int getCompLevel() {
-        return WHITE_BOX.getMethodCompilationLevel(method, testCase.isOsr());
+        NMethod nm = NMethod.get(method, testCase.isOsr());
+        return nm == null ? COMP_LEVEL_NONE : nm.comp_level;
     }
 
     protected final boolean isCompilable() {

test/compiler/whitebox/GetNMethodTest.java

+/*
+ * Copyright (c) 2014, 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.
+ *
+ */
+
+import sun.hotspot.code.NMethod;
+
+/*
+ * @test GetNMethodTest
+ * @bug 8038240
+ * @library /testlibrary /testlibrary/whitebox
+ * @build GetNMethodTest
+ * @run main ClassFileInstaller sun.hotspot.WhiteBox
+ * @run main/othervm -Xbootclasspath/a:. -Xmixed -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -XX:CompileCommand=compileonly,SimpleTestCase$Helper::* GetNMethodTest
+ * @summary testing of WB::getNMethod()
+ * @author igor.ignatyev@oracle.com
+ */
+public class GetNMethodTest extends CompilerWhiteBoxTest {
+    public static void main(String[] args) throws Exception {
+        CompilerWhiteBoxTest.main(GetNMethodTest::new, args);
+    }
+
+    private GetNMethodTest(TestCase testCase) {
+        super(testCase);
+        // to prevent inlining of #method
+        WHITE_BOX.testSetDontInlineMethod(method, true);
+    }
+
+    @Override
+    protected void test() throws Exception {
+        checkNotCompiled();
+
+        compile();
+        checkCompiled();
+        NMethod nmethod = NMethod.get(method, testCase.isOsr());
+        if (IS_VERBOSE) {
+            System.out.println("nmethod = " + nmethod);
+        }
+        if (nmethod == null) {
+            throw new RuntimeException("nmethod of compiled method is null");
+        }
+        if (nmethod.insts.length == 0) {
+            throw new RuntimeException("compiled method's instructions is empty");
+        }
+        deoptimize();
+        checkNotCompiled();
+        nmethod = NMethod.get(method, testCase.isOsr());
+        if (nmethod != null) {
+            throw new RuntimeException("nmethod of non-compiled method isn't null");
+        }
+    }
+}

test/testlibrary/whitebox/sun/hotspot/WhiteBox.java

 /*
- * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2014, 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
@@ -135,6 +135,7 @@ public class WhiteBox {
   public native boolean enqueueMethodForCompilation(Executable method, int compLevel, int entry_bci);
   public native void    clearMethodState(Executable method);
   public native int     getMethodEntryBci(Executable method);
+  public native Object[] getNMethod(Executable method, boolean isOsr);
 
   // Intered strings
   public native boolean isInStringTable(String str);

test/testlibrary/whitebox/sun/hotspot/code/NMethod.java

+/*
+ * Copyright (c) 2014, 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.
+ *
+ */
+
+package sun.hotspot.code;
+
+import java.lang.reflect.Executable;
+import sun.hotspot.WhiteBox;
+
+public class NMethod {
+  private static final WhiteBox wb = WhiteBox.getWhiteBox();
+  public static NMethod get(Executable method, boolean isOsr) {
+    Object[] obj = wb.getNMethod(method, isOsr);
+    return obj == null ? null : new NMethod(obj);
+  }
+  private NMethod(Object[] obj) {
+    assert obj.length == 2;
+    comp_level = (Integer) obj[0];
+    insts = (byte[]) obj[1];
+  }
+  public byte[] insts;
+  public int comp_level;
+
+  @Override
+  public String toString() {
+    return "NMethod{" +
+        "insts=" + insts +
+        ", comp_level=" + comp_level +
+        '}';
+  }
+}