# HG changeset patch
# User Christos Kotselidis <christos.kotselidis@oracle.com>
# Date 1373625656 -7200
# Node ID c3760150dc29bfd2719620480950e85f3f3c6ced
# Parent  28dc33dc456569dd906fd2ad0124a9e1c7a3779a
Add function to read compressed klass pointers of constant objects natively

diff -r 28dc33dc4565 -r c3760150dc29 graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/HotSpotGraalRuntime.java
--- a/graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/HotSpotGraalRuntime.java	Fri Jul 12 12:24:11 2013 +0200
+++ b/graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/HotSpotGraalRuntime.java	Fri Jul 12 12:40:56 2013 +0200
@@ -153,6 +153,13 @@
     }
 
     /**
+     * Reads a klass pointer from a constant object.
+     */
+    public static long unsafeReadKlassPointer(Object object) {
+        return instance.getCompilerToVM().readUnsafeKlassPointer(object);
+    }
+
+    /**
      * Reads a word value from a given object.
      */
     public static long unsafeReadWord(Object object, long offset) {
diff -r 28dc33dc4565 -r c3760150dc29 graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/bridge/CompilerToVM.java
--- a/graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/bridge/CompilerToVM.java	Fri Jul 12 12:24:11 2013 +0200
+++ b/graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/bridge/CompilerToVM.java	Fri Jul 12 12:40:56 2013 +0200
@@ -216,6 +216,8 @@
 
     Object readUnsafeUncompressedPointer(Object o, long displacement);
 
+    long readUnsafeKlassPointer(Object o);
+
     /**
      * Invalidates the profiling information and restarts profiling upon the next invocation.
      * 
diff -r 28dc33dc4565 -r c3760150dc29 graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/bridge/CompilerToVMImpl.java
--- a/graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/bridge/CompilerToVMImpl.java	Fri Jul 12 12:24:11 2013 +0200
+++ b/graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/bridge/CompilerToVMImpl.java	Fri Jul 12 12:40:56 2013 +0200
@@ -173,6 +173,9 @@
     public native Object readUnsafeUncompressedPointer(Object o, long displacement);
 
     @Override
+    public native long readUnsafeKlassPointer(Object o);
+
+    @Override
     public Object executeCompiledMethod(Object arg1, Object arg2, Object arg3, HotSpotInstalledCode hotspotInstalledCode) throws InvalidInstalledCodeException {
         return executeCompiledMethodIntrinsic(arg1, arg2, arg3, hotspotInstalledCode);
     }
diff -r 28dc33dc4565 -r c3760150dc29 graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/meta/HotSpotRuntime.java
--- a/graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/meta/HotSpotRuntime.java	Fri Jul 12 12:24:11 2013 +0200
+++ b/graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/meta/HotSpotRuntime.java	Fri Jul 12 12:40:56 2013 +0200
@@ -1157,7 +1157,11 @@
             case Int:
                 return Constant.forInt(base == null ? unsafe.getInt(displacement) : unsafe.getInt(base, displacement));
             case Long:
-                return Constant.forLong(base == null ? unsafe.getLong(displacement) : unsafe.getLong(base, displacement));
+                if (displacement == config().hubOffset && this.getGraalRuntime().getRuntime().config.useCompressedKlassPointers) {
+                    return Constant.forLong(this.getGraalRuntime().getCompilerToVM().readUnsafeKlassPointer(base));
+                } else {
+                    return Constant.forLong(base == null ? unsafe.getLong(displacement) : unsafe.getLong(base, displacement));
+                }
             case Float:
                 return Constant.forFloat(base == null ? unsafe.getFloat(displacement) : unsafe.getFloat(base, displacement));
             case Double:
diff -r 28dc33dc4565 -r c3760150dc29 src/share/vm/graal/graalCompilerToVM.cpp
--- a/src/share/vm/graal/graalCompilerToVM.cpp	Fri Jul 12 12:24:11 2013 +0200
+++ b/src/share/vm/graal/graalCompilerToVM.cpp	Fri Jul 12 12:40:56 2013 +0200
@@ -1190,6 +1190,11 @@
   return JNIHandles::make_local(*((oop*)address));
 C2V_END
 
+C2V_VMENTRY(jlong, readUnsafeKlassPointer, (JNIEnv *env, jobject, jobject o))
+  oop resolved_o = JNIHandles::resolve(o);
+  jlong klass = (jlong)(address)resolved_o->klass();
+  return klass;
+C2V_END
 
 #define CC (char*)  /*cast a literal from (const char*)*/
 #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &(c2v_ ## f))
@@ -1269,6 +1274,7 @@
   {CC"reprofile",                     CC"("METASPACE_METHOD")V",                                        FN_PTR(reprofile)},
   {CC"invalidateInstalledCode",       CC"("HS_INSTALLED_CODE")V",                                       FN_PTR(invalidateInstalledCode)},
   {CC"readUnsafeUncompressedPointer", CC"("OBJECT"J)"OBJECT,                                            FN_PTR(readUnsafeUncompressedPointer)},
+  {CC"readUnsafeKlassPointer",        CC"("OBJECT")J",                                                  FN_PTR(readUnsafeKlassPointer)},
 };
 
 int CompilerToVM_methods_count() {