8038756: new WB API :: get/setVMFlag

Reviewed-by: vlivanov, sla

src/share/vm/prims/whitebox.cpp

@@ -501,6 +501,159 @@ WB_ENTRY(void, WB_ClearMethodState(JNIEnv* env, jobject o, jobject method))
   }
 WB_END
 
+template <typename T>
+static bool GetVMFlag(JavaThread* thread, JNIEnv* env, jstring name, T* value, bool (*TAt)(const char*, T*)) {
+  if (name == NULL) {
+    return false;
+  }
+  ThreadToNativeFromVM ttnfv(thread);   // can't be in VM when we call JNI
+  const char* flag_name = env->GetStringUTFChars(name, NULL);
+  bool result = (*TAt)(flag_name, value);
+  env->ReleaseStringUTFChars(name, flag_name);
+  return result;
+}
+
+template <typename T>
+static bool SetVMFlag(JavaThread* thread, JNIEnv* env, jstring name, T* value, bool (*TAtPut)(const char*, T*, Flag::Flags)) {
+  if (name == NULL) {
+    return false;
+  }
+  ThreadToNativeFromVM ttnfv(thread);   // can't be in VM when we call JNI
+  const char* flag_name = env->GetStringUTFChars(name, NULL);
+  bool result = (*TAtPut)(flag_name, value, Flag::INTERNAL);
+  env->ReleaseStringUTFChars(name, flag_name);
+  return result;
+}
+
+template <typename T>
+static jobject box(JavaThread* thread, JNIEnv* env, Symbol* name, Symbol* sig, T value) {
+  ResourceMark rm(thread);
+  jclass clazz = env->FindClass(name->as_C_string());
+  CHECK_JNI_EXCEPTION_(env, NULL);
+  jmethodID methodID = env->GetStaticMethodID(clazz,
+        vmSymbols::valueOf_name()->as_C_string(),
+        sig->as_C_string());
+  CHECK_JNI_EXCEPTION_(env, NULL);
+  jobject result = env->CallStaticObjectMethod(clazz, methodID, value);
+  CHECK_JNI_EXCEPTION_(env, NULL);
+  return result;
+}
+
+static jobject booleanBox(JavaThread* thread, JNIEnv* env, jboolean value) {
+  return box(thread, env, vmSymbols::java_lang_Boolean(), vmSymbols::Boolean_valueOf_signature(), value);
+}
+static jobject integerBox(JavaThread* thread, JNIEnv* env, jint value) {
+  return box(thread, env, vmSymbols::java_lang_Integer(), vmSymbols::Integer_valueOf_signature(), value);
+}
+static jobject longBox(JavaThread* thread, JNIEnv* env, jlong value) {
+  return box(thread, env, vmSymbols::java_lang_Long(), vmSymbols::Long_valueOf_signature(), value);
+}
+/* static jobject floatBox(JavaThread* thread, JNIEnv* env, jfloat value) {
+  return box(thread, env, vmSymbols::java_lang_Float(), vmSymbols::Float_valueOf_signature(), value);
+}*/
+static jobject doubleBox(JavaThread* thread, JNIEnv* env, jdouble value) {
+  return box(thread, env, vmSymbols::java_lang_Double(), vmSymbols::Double_valueOf_signature(), value);
+}
+
+WB_ENTRY(jobject, WB_GetBooleanVMFlag(JNIEnv* env, jobject o, jstring name))
+  bool result;
+  if (GetVMFlag <bool> (thread, env, name, &result, &CommandLineFlags::boolAt)) {
+    ThreadToNativeFromVM ttnfv(thread);   // can't be in VM when we call JNI
+    return booleanBox(thread, env, result);
+  }
+  return NULL;
+WB_END
+
+WB_ENTRY(jobject, WB_GetIntxVMFlag(JNIEnv* env, jobject o, jstring name))
+  intx result;
+  if (GetVMFlag <intx> (thread, env, name, &result, &CommandLineFlags::intxAt)) {
+    ThreadToNativeFromVM ttnfv(thread);   // can't be in VM when we call JNI
+    return longBox(thread, env, result);
+  }
+  return NULL;
+WB_END
+
+WB_ENTRY(jobject, WB_GetUintxVMFlag(JNIEnv* env, jobject o, jstring name))
+  uintx result;
+  if (GetVMFlag <uintx> (thread, env, name, &result, &CommandLineFlags::uintxAt)) {
+    ThreadToNativeFromVM ttnfv(thread);   // can't be in VM when we call JNI
+    return longBox(thread, env, result);
+  }
+  return NULL;
+WB_END
+
+WB_ENTRY(jobject, WB_GetUint64VMFlag(JNIEnv* env, jobject o, jstring name))
+  uint64_t result;
+  if (GetVMFlag <uint64_t> (thread, env, name, &result, &CommandLineFlags::uint64_tAt)) {
+    ThreadToNativeFromVM ttnfv(thread);   // can't be in VM when we call JNI
+    return longBox(thread, env, result);
+  }
+  return NULL;
+WB_END
+
+WB_ENTRY(jobject, WB_GetDoubleVMFlag(JNIEnv* env, jobject o, jstring name))
+  double result;
+  if (GetVMFlag <double> (thread, env, name, &result, &CommandLineFlags::doubleAt)) {
+    ThreadToNativeFromVM ttnfv(thread);   // can't be in VM when we call JNI
+    return doubleBox(thread, env, result);
+  }
+  return NULL;
+WB_END
+
+WB_ENTRY(jstring, WB_GetStringVMFlag(JNIEnv* env, jobject o, jstring name))
+  ccstr ccstrResult;
+  if (GetVMFlag <ccstr> (thread, env, name, &ccstrResult, &CommandLineFlags::ccstrAt)) {
+    ThreadToNativeFromVM ttnfv(thread);   // can't be in VM when we call JNI
+    jstring result = env->NewStringUTF(ccstrResult);
+    CHECK_JNI_EXCEPTION_(env, NULL);
+    return result;
+  }
+  return NULL;
+WB_END
+
+WB_ENTRY(void, WB_SetBooleanVMFlag(JNIEnv* env, jobject o, jstring name, jboolean value))
+  bool result = value == JNI_TRUE ? true : false;
+  SetVMFlag <bool> (thread, env, name, &result, &CommandLineFlags::boolAtPut);
+WB_END
+
+WB_ENTRY(void, WB_SetIntxVMFlag(JNIEnv* env, jobject o, jstring name, jlong value))
+  intx result = value;
+  SetVMFlag <intx> (thread, env, name, &result, &CommandLineFlags::intxAtPut);
+WB_END
+
+WB_ENTRY(void, WB_SetUintxVMFlag(JNIEnv* env, jobject o, jstring name, jlong value))
+  uintx result = value;
+  SetVMFlag <uintx> (thread, env, name, &result, &CommandLineFlags::uintxAtPut);
+WB_END
+
+WB_ENTRY(void, WB_SetUint64VMFlag(JNIEnv* env, jobject o, jstring name, jlong value))
+  uint64_t result = value;
+  SetVMFlag <uint64_t> (thread, env, name, &result, &CommandLineFlags::uint64_tAtPut);
+WB_END
+
+WB_ENTRY(void, WB_SetDoubleVMFlag(JNIEnv* env, jobject o, jstring name, jdouble value))
+  double result = value;
+  SetVMFlag <double> (thread, env, name, &result, &CommandLineFlags::doubleAtPut);
+WB_END
+
+WB_ENTRY(void, WB_SetStringVMFlag(JNIEnv* env, jobject o, jstring name, jstring value))
+  ThreadToNativeFromVM ttnfv(thread);   // can't be in VM when we call JNI
+  const char* ccstrValue = (value == NULL) ? NULL : env->GetStringUTFChars(value, NULL);
+  ccstr ccstrResult = ccstrValue;
+  bool needFree;
+  {
+    ThreadInVMfromNative ttvfn(thread); // back to VM
+    needFree = SetVMFlag <ccstr> (thread, env, name, &ccstrResult, &CommandLineFlags::ccstrAtPut);
+  }
+  if (value != NULL) {
+    env->ReleaseStringUTFChars(value, ccstrValue);
+  }
+  if (needFree) {
+    FREE_C_HEAP_ARRAY(char, ccstrResult, mtInternal);
+  }
+WB_END
+
+
 WB_ENTRY(jboolean, WB_IsInStringTable(JNIEnv* env, jobject o, jstring javaString))
   ResourceMark rm(THREAD);
   int len;
@@ -559,11 +712,7 @@ WB_ENTRY(jobjectArray, WB_GetNMethod(JNIEnv* env, jobject o, jobject method, jbo
     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());
+  jobject obj = integerBox(thread, env, code->comp_level());
   CHECK_JNI_EXCEPTION_(env, NULL);
   env->SetObjectArrayElement(result, 0, obj);
 
@@ -684,7 +833,26 @@ static JNINativeMethod methods[] = {
       CC"(Ljava/lang/reflect/Executable;II)Z",        (void*)&WB_EnqueueMethodForCompilation},
   {CC"clearMethodState",
       CC"(Ljava/lang/reflect/Executable;)V",          (void*)&WB_ClearMethodState},
-  {CC"isInStringTable",   CC"(Ljava/lang/String;)Z",  (void*)&WB_IsInStringTable  },
+  {CC"setBooleanVMFlag",   CC"(Ljava/lang/String;Z)V",(void*)&WB_SetBooleanVMFlag},
+  {CC"setIntxVMFlag",      CC"(Ljava/lang/String;J)V",(void*)&WB_SetIntxVMFlag},
+  {CC"setUintxVMFlag",     CC"(Ljava/lang/String;J)V",(void*)&WB_SetUintxVMFlag},
+  {CC"setUint64VMFlag",    CC"(Ljava/lang/String;J)V",(void*)&WB_SetUint64VMFlag},
+  {CC"setDoubleVMFlag",    CC"(Ljava/lang/String;D)V",(void*)&WB_SetDoubleVMFlag},
+  {CC"setStringVMFlag",    CC"(Ljava/lang/String;Ljava/lang/String;)V",
+                                                      (void*)&WB_SetStringVMFlag},
+  {CC"getBooleanVMFlag",   CC"(Ljava/lang/String;)Ljava/lang/Boolean;",
+                                                      (void*)&WB_GetBooleanVMFlag},
+  {CC"getIntxVMFlag",      CC"(Ljava/lang/String;)Ljava/lang/Long;",
+                                                      (void*)&WB_GetIntxVMFlag},
+  {CC"getUintxVMFlag",     CC"(Ljava/lang/String;)Ljava/lang/Long;",
+                                                      (void*)&WB_GetUintxVMFlag},
+  {CC"getUint64VMFlag",    CC"(Ljava/lang/String;)Ljava/lang/Long;",
+                                                      (void*)&WB_GetUint64VMFlag},
+  {CC"getDoubleVMFlag",    CC"(Ljava/lang/String;)Ljava/lang/Double;",
+                                                      (void*)&WB_GetDoubleVMFlag},
+  {CC"getStringVMFlag",    CC"(Ljava/lang/String;)Ljava/lang/String;",
+                                                      (void*)&WB_GetStringVMFlag},
+  {CC"isInStringTable",    CC"(Ljava/lang/String;)Z", (void*)&WB_IsInStringTable  },
   {CC"fullGC",   CC"()V",                             (void*)&WB_FullGC },
   {CC"readReservedMemory", CC"()V",                   (void*)&WB_ReadReservedMemory },
   {CC"getCPUFeatures",     CC"()Ljava/lang/String;",  (void*)&WB_GetCPUFeatures     },

src/share/vm/runtime/globals.cpp

@@ -611,7 +611,7 @@ static void trace_flag_changed(const char* name, const T old_value, const T new_
   e.commit();
 }
 
-bool CommandLineFlags::boolAt(char* name, size_t len, bool* value) {
+bool CommandLineFlags::boolAt(const char* name, size_t len, bool* value) {
   Flag* result = Flag::find_flag(name, len);
   if (result == NULL) return false;
   if (!result->is_bool()) return false;
@@ -619,7 +619,7 @@ bool CommandLineFlags::boolAt(char* name, size_t len, bool* value) {
   return true;
 }
 
-bool CommandLineFlags::boolAtPut(char* name, size_t len, bool* value, Flag::Flags origin) {
+bool CommandLineFlags::boolAtPut(const char* name, size_t len, bool* value, Flag::Flags origin) {
   Flag* result = Flag::find_flag(name, len);
   if (result == NULL) return false;
   if (!result->is_bool()) return false;
@@ -639,7 +639,7 @@ void CommandLineFlagsEx::boolAtPut(CommandLineFlagWithType flag, bool value, Fla
   faddr->set_origin(origin);
 }
 
-bool CommandLineFlags::intxAt(char* name, size_t len, intx* value) {
+bool CommandLineFlags::intxAt(const char* name, size_t len, intx* value) {
   Flag* result = Flag::find_flag(name, len);
   if (result == NULL) return false;
   if (!result->is_intx()) return false;
@@ -647,7 +647,7 @@ bool CommandLineFlags::intxAt(char* name, size_t len, intx* value) {
   return true;
 }
 
-bool CommandLineFlags::intxAtPut(char* name, size_t len, intx* value, Flag::Flags origin) {
+bool CommandLineFlags::intxAtPut(const char* name, size_t len, intx* value, Flag::Flags origin) {
   Flag* result = Flag::find_flag(name, len);
   if (result == NULL) return false;
   if (!result->is_intx()) return false;
@@ -667,7 +667,7 @@ void CommandLineFlagsEx::intxAtPut(CommandLineFlagWithType flag, intx value, Fla
   faddr->set_origin(origin);
 }
 
-bool CommandLineFlags::uintxAt(char* name, size_t len, uintx* value) {
+bool CommandLineFlags::uintxAt(const char* name, size_t len, uintx* value) {
   Flag* result = Flag::find_flag(name, len);
   if (result == NULL) return false;
   if (!result->is_uintx()) return false;
@@ -675,7 +675,7 @@ bool CommandLineFlags::uintxAt(char* name, size_t len, uintx* value) {
   return true;
 }
 
-bool CommandLineFlags::uintxAtPut(char* name, size_t len, uintx* value, Flag::Flags origin) {
+bool CommandLineFlags::uintxAtPut(const char* name, size_t len, uintx* value, Flag::Flags origin) {
   Flag* result = Flag::find_flag(name, len);
   if (result == NULL) return false;
   if (!result->is_uintx()) return false;
@@ -695,7 +695,7 @@ void CommandLineFlagsEx::uintxAtPut(CommandLineFlagWithType flag, uintx value, F
   faddr->set_origin(origin);
 }
 
-bool CommandLineFlags::uint64_tAt(char* name, size_t len, uint64_t* value) {
+bool CommandLineFlags::uint64_tAt(const char* name, size_t len, uint64_t* value) {
   Flag* result = Flag::find_flag(name, len);
   if (result == NULL) return false;
   if (!result->is_uint64_t()) return false;
@@ -703,7 +703,7 @@ bool CommandLineFlags::uint64_tAt(char* name, size_t len, uint64_t* value) {
   return true;
 }
 
-bool CommandLineFlags::uint64_tAtPut(char* name, size_t len, uint64_t* value, Flag::Flags origin) {
+bool CommandLineFlags::uint64_tAtPut(const char* name, size_t len, uint64_t* value, Flag::Flags origin) {
   Flag* result = Flag::find_flag(name, len);
   if (result == NULL) return false;
   if (!result->is_uint64_t()) return false;
@@ -723,7 +723,7 @@ void CommandLineFlagsEx::uint64_tAtPut(CommandLineFlagWithType flag, uint64_t va
   faddr->set_origin(origin);
 }
 
-bool CommandLineFlags::doubleAt(char* name, size_t len, double* value) {
+bool CommandLineFlags::doubleAt(const char* name, size_t len, double* value) {
   Flag* result = Flag::find_flag(name, len);
   if (result == NULL) return false;
   if (!result->is_double()) return false;
@@ -731,7 +731,7 @@ bool CommandLineFlags::doubleAt(char* name, size_t len, double* value) {
   return true;
 }
 
-bool CommandLineFlags::doubleAtPut(char* name, size_t len, double* value, Flag::Flags origin) {
+bool CommandLineFlags::doubleAtPut(const char* name, size_t len, double* value, Flag::Flags origin) {
   Flag* result = Flag::find_flag(name, len);
   if (result == NULL) return false;
   if (!result->is_double()) return false;
@@ -751,7 +751,7 @@ void CommandLineFlagsEx::doubleAtPut(CommandLineFlagWithType flag, double value,
   faddr->set_origin(origin);
 }
 
-bool CommandLineFlags::ccstrAt(char* name, size_t len, ccstr* value) {
+bool CommandLineFlags::ccstrAt(const char* name, size_t len, ccstr* value) {
   Flag* result = Flag::find_flag(name, len);
   if (result == NULL) return false;
   if (!result->is_ccstr()) return false;
@@ -759,7 +759,7 @@ bool CommandLineFlags::ccstrAt(char* name, size_t len, ccstr* value) {
   return true;
 }
 
-bool CommandLineFlags::ccstrAtPut(char* name, size_t len, ccstr* value, Flag::Flags origin) {
+bool CommandLineFlags::ccstrAtPut(const char* name, size_t len, ccstr* value, Flag::Flags origin) {
   Flag* result = Flag::find_flag(name, len);
   if (result == NULL) return false;
   if (!result->is_ccstr()) return false;

src/share/vm/runtime/globals.hpp

@@ -363,37 +363,37 @@ class DoubleFlagSetting {
 
 class CommandLineFlags {
  public:
-  static bool boolAt(char* name, size_t len, bool* value);
-  static bool boolAt(char* name, bool* value)      { return boolAt(name, strlen(name), value); }
-  static bool boolAtPut(char* name, size_t len, bool* value, Flag::Flags origin);
-  static bool boolAtPut(char* name, bool* value, Flag::Flags origin)   { return boolAtPut(name, strlen(name), value, origin); }
-
-  static bool intxAt(char* name, size_t len, intx* value);
-  static bool intxAt(char* name, intx* value)      { return intxAt(name, strlen(name), value); }
-  static bool intxAtPut(char* name, size_t len, intx* value, Flag::Flags origin);
-  static bool intxAtPut(char* name, intx* value, Flag::Flags origin)   { return intxAtPut(name, strlen(name), value, origin); }
-
-  static bool uintxAt(char* name, size_t len, uintx* value);
-  static bool uintxAt(char* name, uintx* value)    { return uintxAt(name, strlen(name), value); }
-  static bool uintxAtPut(char* name, size_t len, uintx* value, Flag::Flags origin);
-  static bool uintxAtPut(char* name, uintx* value, Flag::Flags origin) { return uintxAtPut(name, strlen(name), value, origin); }
-
-  static bool uint64_tAt(char* name, size_t len, uint64_t* value);
-  static bool uint64_tAt(char* name, uint64_t* value) { return uint64_tAt(name, strlen(name), value); }
-  static bool uint64_tAtPut(char* name, size_t len, uint64_t* value, Flag::Flags origin);
-  static bool uint64_tAtPut(char* name, uint64_t* value, Flag::Flags origin) { return uint64_tAtPut(name, strlen(name), value, origin); }
-
-  static bool doubleAt(char* name, size_t len, double* value);
-  static bool doubleAt(char* name, double* value)    { return doubleAt(name, strlen(name), value); }
-  static bool doubleAtPut(char* name, size_t len, double* value, Flag::Flags origin);
-  static bool doubleAtPut(char* name, double* value, Flag::Flags origin) { return doubleAtPut(name, strlen(name), value, origin); }
-
-  static bool ccstrAt(char* name, size_t len, ccstr* value);
-  static bool ccstrAt(char* name, ccstr* value)    { return ccstrAt(name, strlen(name), value); }
+  static bool boolAt(const char* name, size_t len, bool* value);
+  static bool boolAt(const char* name, bool* value)      { return boolAt(name, strlen(name), value); }
+  static bool boolAtPut(const char* name, size_t len, bool* value, Flag::Flags origin);
+  static bool boolAtPut(const char* name, bool* value, Flag::Flags origin)   { return boolAtPut(name, strlen(name), value, origin); }
+
+  static bool intxAt(const char* name, size_t len, intx* value);
+  static bool intxAt(const char* name, intx* value)      { return intxAt(name, strlen(name), value); }
+  static bool intxAtPut(const char* name, size_t len, intx* value, Flag::Flags origin);
+  static bool intxAtPut(const char* name, intx* value, Flag::Flags origin)   { return intxAtPut(name, strlen(name), value, origin); }
+
+  static bool uintxAt(const char* name, size_t len, uintx* value);
+  static bool uintxAt(const char* name, uintx* value)    { return uintxAt(name, strlen(name), value); }
+  static bool uintxAtPut(const char* name, size_t len, uintx* value, Flag::Flags origin);
+  static bool uintxAtPut(const char* name, uintx* value, Flag::Flags origin) { return uintxAtPut(name, strlen(name), value, origin); }
+
+  static bool uint64_tAt(const char* name, size_t len, uint64_t* value);
+  static bool uint64_tAt(const char* name, uint64_t* value) { return uint64_tAt(name, strlen(name), value); }
+  static bool uint64_tAtPut(const char* name, size_t len, uint64_t* value, Flag::Flags origin);
+  static bool uint64_tAtPut(const char* name, uint64_t* value, Flag::Flags origin) { return uint64_tAtPut(name, strlen(name), value, origin); }
+
+  static bool doubleAt(const char* name, size_t len, double* value);
+  static bool doubleAt(const char* name, double* value)    { return doubleAt(name, strlen(name), value); }
+  static bool doubleAtPut(const char* name, size_t len, double* value, Flag::Flags origin);
+  static bool doubleAtPut(const char* name, double* value, Flag::Flags origin) { return doubleAtPut(name, strlen(name), value, origin); }
+
+  static bool ccstrAt(const char* name, size_t len, ccstr* value);
+  static bool ccstrAt(const char* name, ccstr* value)    { return ccstrAt(name, strlen(name), value); }
   // Contract:  Flag will make private copy of the incoming value.
   // Outgoing value is always malloc-ed, and caller MUST call free.
-  static bool ccstrAtPut(char* name, size_t len, ccstr* value, Flag::Flags origin);
-  static bool ccstrAtPut(char* name, ccstr* value, Flag::Flags origin) { return ccstrAtPut(name, strlen(name), value, origin); }
+  static bool ccstrAtPut(const char* name, size_t len, ccstr* value, Flag::Flags origin);
+  static bool ccstrAtPut(const char* name, ccstr* value, Flag::Flags origin) { return ccstrAtPut(name, strlen(name), value, origin); }
 
   // Returns false if name is not a command line flag.
   static bool wasSetOnCmdline(const char* name, bool* value);

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

@@ -129,7 +129,7 @@ public class WhiteBox {
   }
   public native int     getCompileQueueSize(int compLevel);
   public native boolean testSetForceInlineMethod(Executable method, boolean value);
-  public boolean        enqueueMethodForCompilation(Executable method, int compLevel) {
+  public        boolean enqueueMethodForCompilation(Executable method, int compLevel) {
     return enqueueMethodForCompilation(method, compLevel, -1 /*InvocationEntryBci*/);
   }
   public native boolean enqueueMethodForCompilation(Executable method, int compLevel, int entry_bci);
@@ -154,4 +154,17 @@ public class WhiteBox {
   // CPU features
   public native String getCPUFeatures();
 
+  // VM flags
+  public native void    setBooleanVMFlag(String name, boolean value);
+  public native void    setIntxVMFlag(String name, long value);
+  public native void    setUintxVMFlag(String name, long value);
+  public native void    setUint64VMFlag(String name, long value);
+  public native void    setStringVMFlag(String name, String value);
+  public native void    setDoubleVMFlag(String name, double value);
+  public native Boolean getBooleanVMFlag(String name);
+  public native Long    getIntxVMFlag(String name);
+  public native Long    getUintxVMFlag(String name);
+  public native Long    getUint64VMFlag(String name);
+  public native String  getStringVMFlag(String name);
+  public native Double  getDoubleVMFlag(String name);
 }

test/testlibrary_tests/whitebox/vm_flags/BooleanTest.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.
+ */
+
+/*
+ * @test BooleanTest
+ * @bug 8028756
+ * @library /testlibrary /testlibrary/whitebox
+ * @build BooleanTest
+ * @run main ClassFileInstaller sun.hotspot.WhiteBox
+ * @run main/othervm/timeout=600 -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI BooleanTest
+ * @summary testing of WB::set/getBooleanVMFlag()
+ * @author igor.ignatyev@oracle.com
+ */
+
+import sun.hotspot.WhiteBox;
+import com.oracle.java.testlibrary.*;
+import sun.management.*;
+import com.sun.management.*;
+
+public class BooleanTest {
+    private static final WhiteBox WHITE_BOX = WhiteBox.getWhiteBox();
+    private static final Boolean[] TESTS = {true, false, true, true, false};
+    private static final String TEST_NAME = "BooleanTest";
+    private static final String FLAG_NAME = "PrintCompilation";
+    private static final String METHOD = TEST_NAME + "::method";
+    private static final String METHOD1 = METHOD + "1";
+    private static final String METHOD2 = METHOD + "2";
+
+    public static void main(String[] args) throws Exception {
+        if (args.length == 0) {
+            VmFlagTest.runTest(FLAG_NAME, TESTS,
+                VmFlagTest.WHITE_BOX::setBooleanVMFlag,
+                VmFlagTest.WHITE_BOX::getBooleanVMFlag);
+            testFunctional(false);
+            testFunctional(true);
+        } else {
+            boolean value = Boolean.valueOf(args[0]);
+            method1();
+            VmFlagTest.WHITE_BOX.setBooleanVMFlag(FLAG_NAME, value);
+            method2();
+        }
+    }
+
+    private static void testFunctional(boolean value) throws Exception {
+        ProcessBuilder pb = ProcessTools.createJavaProcessBuilder(
+            "-Xbootclasspath/a:.",
+            "-XX:+UnlockDiagnosticVMOptions",
+            "-XX:+WhiteBoxAPI",
+            "-Xcomp",
+            "-XX:CompileCommand=compileonly," + METHOD + "*",
+            "-XX:" + (value ? "-" : "+") + FLAG_NAME,
+            TEST_NAME,
+            "" + value);
+        OutputAnalyzer out = new OutputAnalyzer(pb.start());
+        if (value) {
+            out.shouldNotContain(METHOD1);
+            out.shouldContain(METHOD2);
+        } else {
+            out.shouldContain(METHOD1);
+            out.shouldNotContain(METHOD2);
+        }
+    }
+
+    private static void method1() { }
+    private static void method2() { }
+}
+

test/testlibrary_tests/whitebox/vm_flags/DoubleTest.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.
+ */
+
+/*
+ * @test DoubleTest
+ * @bug 8028756
+ * @library /testlibrary /testlibrary/whitebox
+ * @build DoubleTest
+ * @run main ClassFileInstaller sun.hotspot.WhiteBox
+ * @run main/othervm/timeout=600 -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI DoubleTest
+ * @summary testing of WB::set/getDoubleVMFlag()
+ * @author igor.ignatyev@oracle.com
+ */
+
+public class DoubleTest {
+    private static final String FLAG_NAME = null;
+    private static final Double[] TESTS = {0d, -0d, -1d, 1d,
+            Double.MAX_VALUE, Double.MIN_VALUE, Double.NaN,
+            Double.NEGATIVE_INFINITY, Double.POSITIVE_INFINITY};
+
+    public static void main(String[] args) throws Exception {
+        VmFlagTest.runTest(FLAG_NAME, TESTS,
+            VmFlagTest.WHITE_BOX::setDoubleVMFlag,
+            VmFlagTest.WHITE_BOX::getDoubleVMFlag);
+    }
+}
+

test/testlibrary_tests/whitebox/vm_flags/IntxTest.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.
+ */
+
+/*
+ * @test IntxTest
+ * @bug 8028756
+ * @library /testlibrary /testlibrary/whitebox
+ * @build IntxTest
+ * @run main ClassFileInstaller sun.hotspot.WhiteBox
+ * @run main/othervm/timeout=600 -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI IntxTest
+ * @summary testing of WB::set/getIntxVMFlag()
+ * @author igor.ignatyev@oracle.com
+ */
+
+public class IntxTest {
+    private static final String FLAG_NAME = "OnStackReplacePercentage";
+    private static final Long[] TESTS = {0L, 100L, -1L,
+            (long) Integer.MAX_VALUE, (long) Integer.MIN_VALUE};
+
+    public static void main(String[] args) throws Exception {
+        VmFlagTest.runTest(FLAG_NAME, TESTS,
+            VmFlagTest.WHITE_BOX::setIntxVMFlag,
+            VmFlagTest.WHITE_BOX::getIntxVMFlag);
+    }
+}
+

test/testlibrary_tests/whitebox/vm_flags/StringTest.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.
+ */
+
+/*
+ * @test StringTest
+ * @bug 8028756
+ * @library /testlibrary /testlibrary/whitebox
+ * @build StringTest
+ * @run main ClassFileInstaller sun.hotspot.WhiteBox
+ * @run main/othervm/timeout=600 -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI StringTest
+ * @summary testing of WB::set/getStringVMFlag()
+ * @author igor.ignatyev@oracle.com
+ */
+
+public class StringTest {
+    private static final String FLAG_NAME = "CompileOnly";
+    private static final String[] TESTS = {"StringTest::*", ""};
+
+    public static void main(String[] args) throws Exception {
+        VmFlagTest.runTest(FLAG_NAME, TESTS,
+            VmFlagTest.WHITE_BOX::setStringVMFlag,
+            VmFlagTest.WHITE_BOX::getStringVMFlag);
+    }
+}
+

test/testlibrary_tests/whitebox/vm_flags/Uint64Test.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.
+ */
+
+/*
+ * @test Uint64Test
+ * @bug 8028756
+ * @library /testlibrary /testlibrary/whitebox
+ * @build Uint64Test
+ * @run main ClassFileInstaller sun.hotspot.WhiteBox
+ * @run main/othervm/timeout=600 -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI Uint64Test
+ * @summary testing of WB::set/getUint64VMFlag()
+ * @author igor.ignatyev@oracle.com
+ */
+
+public class Uint64Test {
+    private static final String FLAG_NAME = "MaxRAM";
+    private static final Long[] TESTS = {0L, 100L, (long) Integer.MAX_VALUE,
+            -1L, Long.MAX_VALUE, Long.MIN_VALUE};
+
+    public static void main(String[] args) throws Exception {
+        VmFlagTest.runTest(FLAG_NAME, TESTS,
+            VmFlagTest.WHITE_BOX::setUint64VMFlag,
+            VmFlagTest.WHITE_BOX::getUint64VMFlag);
+    }
+}
+

test/testlibrary_tests/whitebox/vm_flags/UintxTest.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.
+ */
+
+/*
+ * @test UintxTest
+ * @bug 8028756
+ * @library /testlibrary /testlibrary/whitebox
+ * @build UintxTest
+ * @run main ClassFileInstaller sun.hotspot.WhiteBox
+ * @run main/othervm/timeout=600 -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI UintxTest
+ * @summary testing of WB::set/getUintxVMFlag()
+ * @author igor.ignatyev@oracle.com
+ */
+import com.oracle.java.testlibrary.Platform;
+
+public class UintxTest {
+    private static final String FLAG_NAME = "TypeProfileLevel";
+    private static final Long[] TESTS = {0L, 100L, (long) Integer.MAX_VALUE,
+        (1L << 32L) - 1L, 1L << 32L};
+    private static final Long[] EXPECTED_64 = TESTS;
+    private static final Long[] EXPECTED_32 = {0L, 100L,
+        (long) Integer.MAX_VALUE, (1L << 32L) - 1L, 0L};
+
+    public static void main(String[] args) throws Exception {
+        VmFlagTest.runTest(FLAG_NAME, TESTS,
+            Platform.is64bit() ? EXPECTED_64 : EXPECTED_32,
+            VmFlagTest.WHITE_BOX::setUintxVMFlag,
+            VmFlagTest.WHITE_BOX::getUintxVMFlag);
+    }
+}
+

test/testlibrary_tests/whitebox/vm_flags/VmFlagTest.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 java.util.Objects;
+import java.util.function.BiConsumer;
+import java.util.function.Function;
+import sun.hotspot.WhiteBox;
+import sun.management.*;
+import com.sun.management.*;
+import com.oracle.java.testlibrary.*;
+
+public final class VmFlagTest<T> {
+    public static final WhiteBox WHITE_BOX = WhiteBox.getWhiteBox();
+
+    private static final String NONEXISTENT_FLAG = "NonexistentFlag";
+    private final String flagName;
+    private final BiConsumer<T, T> test;
+    private final BiConsumer<String, T> set;
+    private final Function<String, T> get;
+
+    protected VmFlagTest(String flagName, BiConsumer<String, T> set,
+            Function<String, T> get, boolean isPositive) {
+        this.flagName = flagName;
+        this.set = set;
+        this.get = get;
+        if (isPositive) {
+            test = this::testPositive;
+        } else {
+            test = this::testNegative;
+        }
+    }
+
+    private void setNewValue(T value) {
+        set.accept(flagName, value);
+    }
+
+    private T getValue() {
+        T t = get.apply(flagName);
+        System.out.println("T = " + t);
+        return t;
+    }
+
+    protected static <T> void runTest(String existentFlag, T[] tests,
+            BiConsumer<String, T> set, Function<String, T> get) {
+        runTest(existentFlag, tests, tests, set, get);
+    }
+
+    protected static <T> void runTest(String existentFlag, T[] tests,
+            T[] results, BiConsumer<String, T> set, Function<String, T> get) {
+        if (existentFlag != null) {
+            new VmFlagTest(existentFlag, set, get, true).test(tests, results);
+        }
+        new VmFlagTest(NONEXISTENT_FLAG, set, get, false).test(tests, results);
+    }
+
+    public final void test(T[] tests, T[] results) {
+        Asserts.assertEQ(tests.length, results.length, "[TESTBUG] tests.length != results.length");
+        for (int i = 0, n = tests.length ; i < n; ++i) {
+            test.accept(tests[i], results[i]);
+        }
+    }
+
+    protected String getVMOptionAsString() {
+        HotSpotDiagnosticMXBean diagnostic
+                = ManagementFactoryHelper.getDiagnosticMXBean();
+        VMOption tmp;
+        try {
+            tmp = diagnostic.getVMOption(flagName);
+        } catch (IllegalArgumentException e) {
+            tmp = null;
+        }
+        return tmp == null ? null : tmp.getValue();
+    }
+
+    private void testPositive(T value, T expected) {
+        Asserts.assertEQ(getVMOptionAsString(), asString(getValue()));
+        setNewValue(value);
+        String newValue = getVMOptionAsString();
+        Asserts.assertEQ(newValue, asString(expected));
+        Asserts.assertEQ(getVMOptionAsString(), asString(getValue()));
+    }
+
+    private void testNegative(T value, T expected) {
+        String oldValue = getVMOptionAsString();
+        Asserts.assertEQ(oldValue, asString(getValue()));
+        setNewValue(value);
+        String newValue = getVMOptionAsString();
+        Asserts.assertEQ(oldValue, newValue);
+    }
+
+    private String asString(Object value) {
+        return value == null ? null : "" + value;
+    }
+}
+