Class.h (_Jv_IDispatchTable): Make it a struct.

2006-02-09  Bryce McKinlay  <mckinlay@redhat.com>

	* java/lang/Class.h (_Jv_IDispatchTable): Make it a struct. Put 
	'itable' inline, instead of as a pointer.
	(java::lang::Class): Put 'idt' in anonymous union with 'ioffsets'.
	* link.cc (null_idt): Update definition.
	(_Jv_Linker::prepare_constant_time_tables): Allocate klass->idt
	as a single struct. Use _Jv_AllocBytes, not _Jv_AllocRawObj.
	(_Jv_Linker::generate_itable): Update to use 'ioffsets'.
	(_Jv_Linker::find_iindex): Likewise. Update comment.
	* java/lang/natClass.cc	(_Jv_LookupInterfaceMethodIdx): Update for
	_Jv_IDispatchTable change.
	(_Jv_IsAssignableFrom): Likewise.

From-SVN: r110818

2 files changed, 22 insertions, 27 deletions

diff --git a/libjava/java/lang/Class.h b/libjava/java/lang/Class.h
index 62e280c..787e263 100644
--- a/libjava/java/lang/Class.h
+++ b/libjava/java/lang/Class.h
@@ -120,23 +120,14 @@ struct _Jv_Method
   { return this + 1; }
 };
 
-// Interface Dispatch Tables 
-union _Jv_IDispatchTable
+// The table used to resolve interface calls.
+struct _Jv_IDispatchTable
 {
-  struct
-  {
-    // Index into interface's ioffsets.
-    jshort iindex;
-    jshort itable_length;
-    // Class Interface dispatch table.
-    void **itable;
-  } cls;
-
-  struct
-  {
-    // Offsets into implementation class itables.
-    jshort *ioffsets;
-  } iface;
+  // Index into interface's ioffsets.
+  jshort iindex;
+  jshort itable_length;
+  // Class Interface dispatch table.
+  void *itable[0];
 };
 
 // Used by _Jv_Linker::get_interfaces ()
@@ -600,8 +591,13 @@ private:
   jshort depth;
   // Vector of this class's superclasses, ordered by decreasing depth.
   jclass *ancestors;
-  // Interface Dispatch Table.
-  _Jv_IDispatchTable *idt;
+  // In a regular class, this field points to the Class Interface Dispatch 
+  // Table. In an interface, it points to the ioffsets table.
+  union 
+  {
+    _Jv_IDispatchTable *idt;
+    jshort *ioffsets;
+  };
   // Pointer to the class that represents an array of this class.
   jclass arrayclass;
   // Security Domain to which this class belongs (or null).
diff --git a/libjava/java/lang/natClass.cc b/libjava/java/lang/natClass.cc
index 04a5bc4..8972cb2 100644
--- a/libjava/java/lang/natClass.cc
+++ b/libjava/java/lang/natClass.cc
@@ -985,8 +985,8 @@ void *
 _Jv_LookupInterfaceMethodIdx (jclass klass, jclass iface, int method_idx)
 {
   _Jv_IDispatchTable *cldt = klass->idt;
-  int idx = iface->idt->iface.ioffsets[cldt->cls.iindex] + method_idx;
-  return cldt->cls.itable[idx];
+  int idx = iface->ioffsets[cldt->iindex] + method_idx;
+  return cldt->itable[idx];
 }
 
 jboolean
@@ -1013,16 +1013,15 @@ _Jv_IsAssignableFrom (jclass source, jclass target)
         return _Jv_InterfaceAssignableFrom (source, target);
 
       _Jv_IDispatchTable *cl_idt = source->idt;
-      _Jv_IDispatchTable *if_idt = target->idt;
 
-      if (__builtin_expect ((if_idt == NULL), false))
+      if (__builtin_expect ((target->ioffsets == NULL), false))
 	return false; // No class implementing TARGET has been loaded.    
-      jshort cl_iindex = cl_idt->cls.iindex;
-      if (cl_iindex < if_idt->iface.ioffsets[0])
+      jshort cl_iindex = cl_idt->iindex;
+      if (cl_iindex < target->ioffsets[0])
         {
-	  jshort offset = if_idt->iface.ioffsets[cl_iindex];
-	  if (offset != -1 && offset < cl_idt->cls.itable_length
-	      && cl_idt->cls.itable[offset] == target)
+	  jshort offset = target->ioffsets[cl_iindex];
+	  if (offset != -1 && offset < cl_idt->itable_length
+	      && cl_idt->itable[offset] == target)
 	    return true;
 	}
       return false;