hotspot/src/share/vm/oops/cpCacheOop.cpp
changeset 1 489c9b5090e2
child 360 21d113ecbf6a
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/oops/cpCacheOop.cpp	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,449 @@
+/*
+ * Copyright 1998-2006 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+#include "incls/_precompiled.incl"
+#include "incls/_cpCacheOop.cpp.incl"
+
+
+// Implememtation of ConstantPoolCacheEntry
+
+void ConstantPoolCacheEntry::set_initial_state(int index) {
+  assert(0 <= index && index < 0x10000, "sanity check");
+  _indices = index;
+}
+
+
+int ConstantPoolCacheEntry::as_flags(TosState state, bool is_final,
+                    bool is_vfinal, bool is_volatile,
+                    bool is_method_interface, bool is_method) {
+  int f = state;
+
+  assert( state < number_of_states, "Invalid state in as_flags");
+
+  f <<= 1;
+  if (is_final) f |= 1;
+  f <<= 1;
+  if (is_vfinal) f |= 1;
+  f <<= 1;
+  if (is_volatile) f |= 1;
+  f <<= 1;
+  if (is_method_interface) f |= 1;
+  f <<= 1;
+  if (is_method) f |= 1;
+  f <<= ConstantPoolCacheEntry::hotSwapBit;
+  // Preserve existing flag bit values
+#ifdef ASSERT
+  int old_state = ((_flags >> tosBits) & 0x0F);
+  assert(old_state == 0 || old_state == state,
+         "inconsistent cpCache flags state");
+#endif
+  return (_flags | f) ;
+}
+
+void ConstantPoolCacheEntry::set_bytecode_1(Bytecodes::Code code) {
+#ifdef ASSERT
+  // Read once.
+  volatile Bytecodes::Code c = bytecode_1();
+  assert(c == 0 || c == code || code == 0, "update must be consistent");
+#endif
+  // Need to flush pending stores here before bytecode is written.
+  OrderAccess::release_store_ptr(&_indices, _indices | ((u_char)code << 16));
+}
+
+void ConstantPoolCacheEntry::set_bytecode_2(Bytecodes::Code code) {
+#ifdef ASSERT
+  // Read once.
+  volatile Bytecodes::Code c = bytecode_2();
+  assert(c == 0 || c == code || code == 0, "update must be consistent");
+#endif
+  // Need to flush pending stores here before bytecode is written.
+  OrderAccess::release_store_ptr(&_indices, _indices | ((u_char)code << 24));
+}
+
+#ifdef ASSERT
+// It is possible to have two different dummy methodOops created
+// when the resolve code for invoke interface executes concurrently
+// Hence the assertion below is weakened a bit for the invokeinterface
+// case.
+bool ConstantPoolCacheEntry::same_methodOop(oop cur_f1, oop f1) {
+  return (cur_f1 == f1 || ((methodOop)cur_f1)->name() ==
+         ((methodOop)f1)->name() || ((methodOop)cur_f1)->signature() ==
+         ((methodOop)f1)->signature());
+}
+#endif
+
+// Note that concurrent update of both bytecodes can leave one of them
+// reset to zero.  This is harmless; the interpreter will simply re-resolve
+// the damaged entry.  More seriously, the memory synchronization is needed
+// to flush other fields (f1, f2) completely to memory before the bytecodes
+// are updated, lest other processors see a non-zero bytecode but zero f1/f2.
+void ConstantPoolCacheEntry::set_field(Bytecodes::Code get_code,
+                                       Bytecodes::Code put_code,
+                                       KlassHandle field_holder,
+                                       int orig_field_index,
+                                       int field_offset,
+                                       TosState field_type,
+                                       bool is_final,
+                                       bool is_volatile) {
+  set_f1(field_holder());
+  set_f2(field_offset);
+  // The field index is used by jvm/ti and is the index into fields() array
+  // in holder instanceKlass.  This is scaled by instanceKlass::next_offset.
+  assert((orig_field_index % instanceKlass::next_offset) == 0, "wierd index");
+  const int field_index = orig_field_index / instanceKlass::next_offset;
+  assert(field_index <= field_index_mask,
+         "field index does not fit in low flag bits");
+  set_flags(as_flags(field_type, is_final, false, is_volatile, false, false) |
+            (field_index & field_index_mask));
+  set_bytecode_1(get_code);
+  set_bytecode_2(put_code);
+  NOT_PRODUCT(verify(tty));
+}
+
+int  ConstantPoolCacheEntry::field_index() const {
+  return (_flags & field_index_mask) * instanceKlass::next_offset;
+}
+
+void ConstantPoolCacheEntry::set_method(Bytecodes::Code invoke_code,
+                                        methodHandle method,
+                                        int vtable_index) {
+
+  assert(method->interpreter_entry() != NULL, "should have been set at this point");
+  assert(!method->is_obsolete(),  "attempt to write obsolete method to cpCache");
+  bool change_to_virtual = (invoke_code == Bytecodes::_invokeinterface);
+
+  int byte_no = -1;
+  bool needs_vfinal_flag = false;
+  switch (invoke_code) {
+    case Bytecodes::_invokevirtual:
+    case Bytecodes::_invokeinterface: {
+        if (method->can_be_statically_bound()) {
+          set_f2((intptr_t)method());
+          needs_vfinal_flag = true;
+        } else {
+          assert(vtable_index >= 0, "valid index");
+          set_f2(vtable_index);
+        }
+        byte_no = 2;
+        break;
+    }
+    case Bytecodes::_invokespecial:
+      // Preserve the value of the vfinal flag on invokevirtual bytecode
+      // which may be shared with this constant pool cache entry.
+      needs_vfinal_flag = is_resolved(Bytecodes::_invokevirtual) && is_vfinal();
+      // fall through
+    case Bytecodes::_invokestatic:
+      set_f1(method());
+      byte_no = 1;
+      break;
+    default:
+      ShouldNotReachHere();
+      break;
+  }
+
+  set_flags(as_flags(as_TosState(method->result_type()),
+                     method->is_final_method(),
+                     needs_vfinal_flag,
+                     false,
+                     change_to_virtual,
+                     true)|
+            method()->size_of_parameters());
+
+  // Note:  byte_no also appears in TemplateTable::resolve.
+  if (byte_no == 1) {
+    set_bytecode_1(invoke_code);
+  } else if (byte_no == 2)  {
+    if (change_to_virtual) {
+      // NOTE: THIS IS A HACK - BE VERY CAREFUL!!!
+      //
+      // Workaround for the case where we encounter an invokeinterface, but we
+      // should really have an _invokevirtual since the resolved method is a
+      // virtual method in java.lang.Object. This is a corner case in the spec
+      // but is presumably legal. javac does not generate this code.
+      //
+      // We set bytecode_1() to _invokeinterface, because that is the
+      // bytecode # used by the interpreter to see if it is resolved.
+      // We set bytecode_2() to _invokevirtual.
+      // See also interpreterRuntime.cpp. (8/25/2000)
+      // Only set resolved for the invokeinterface case if method is public.
+      // Otherwise, the method needs to be reresolved with caller for each
+      // interface call.
+      if (method->is_public()) set_bytecode_1(invoke_code);
+      set_bytecode_2(Bytecodes::_invokevirtual);
+    } else {
+      set_bytecode_2(invoke_code);
+    }
+  } else {
+    ShouldNotReachHere();
+  }
+  NOT_PRODUCT(verify(tty));
+}
+
+
+void ConstantPoolCacheEntry::set_interface_call(methodHandle method, int index) {
+  klassOop interf = method->method_holder();
+  assert(instanceKlass::cast(interf)->is_interface(), "must be an interface");
+  set_f1(interf);
+  set_f2(index);
+  set_flags(as_flags(as_TosState(method->result_type()), method->is_final_method(), false, false, false, true) | method()->size_of_parameters());
+  set_bytecode_1(Bytecodes::_invokeinterface);
+}
+
+
+class LocalOopClosure: public OopClosure {
+ private:
+  void (*_f)(oop*);
+
+ public:
+  LocalOopClosure(void f(oop*))        { _f = f; }
+  virtual void do_oop(oop* o)          { _f(o); }
+};
+
+
+void ConstantPoolCacheEntry::oops_do(void f(oop*)) {
+  LocalOopClosure blk(f);
+  oop_iterate(&blk);
+}
+
+
+void ConstantPoolCacheEntry::oop_iterate(OopClosure* blk) {
+  assert(in_words(size()) == 4, "check code below - may need adjustment");
+  // field[1] is always oop or NULL
+  blk->do_oop((oop*)&_f1);
+  if (is_vfinal()) {
+    blk->do_oop((oop*)&_f2);
+  }
+}
+
+
+void ConstantPoolCacheEntry::oop_iterate_m(OopClosure* blk, MemRegion mr) {
+  assert(in_words(size()) == 4, "check code below - may need adjustment");
+  // field[1] is always oop or NULL
+  if (mr.contains((oop *)&_f1)) blk->do_oop((oop*)&_f1);
+  if (is_vfinal()) {
+    if (mr.contains((oop *)&_f2)) blk->do_oop((oop*)&_f2);
+  }
+}
+
+
+void ConstantPoolCacheEntry::follow_contents() {
+  assert(in_words(size()) == 4, "check code below - may need adjustment");
+  // field[1] is always oop or NULL
+  MarkSweep::mark_and_push((oop*)&_f1);
+  if (is_vfinal()) {
+    MarkSweep::mark_and_push((oop*)&_f2);
+  }
+}
+
+#ifndef SERIALGC
+void ConstantPoolCacheEntry::follow_contents(ParCompactionManager* cm) {
+  assert(in_words(size()) == 4, "check code below - may need adjustment");
+  // field[1] is always oop or NULL
+  PSParallelCompact::mark_and_push(cm, (oop*)&_f1);
+  if (is_vfinal()) {
+    PSParallelCompact::mark_and_push(cm, (oop*)&_f2);
+  }
+}
+#endif // SERIALGC
+
+void ConstantPoolCacheEntry::adjust_pointers() {
+  assert(in_words(size()) == 4, "check code below - may need adjustment");
+  // field[1] is always oop or NULL
+  MarkSweep::adjust_pointer((oop*)&_f1);
+  if (is_vfinal()) {
+    MarkSweep::adjust_pointer((oop*)&_f2);
+  }
+}
+
+#ifndef SERIALGC
+void ConstantPoolCacheEntry::update_pointers() {
+  assert(in_words(size()) == 4, "check code below - may need adjustment");
+  // field[1] is always oop or NULL
+  PSParallelCompact::adjust_pointer((oop*)&_f1);
+  if (is_vfinal()) {
+    PSParallelCompact::adjust_pointer((oop*)&_f2);
+  }
+}
+
+void ConstantPoolCacheEntry::update_pointers(HeapWord* beg_addr,
+                                             HeapWord* end_addr) {
+  assert(in_words(size()) == 4, "check code below - may need adjustment");
+  // field[1] is always oop or NULL
+  PSParallelCompact::adjust_pointer((oop*)&_f1, beg_addr, end_addr);
+  if (is_vfinal()) {
+    PSParallelCompact::adjust_pointer((oop*)&_f2, beg_addr, end_addr);
+  }
+}
+#endif // SERIALGC
+
+// RedefineClasses() API support:
+// If this constantPoolCacheEntry refers to old_method then update it
+// to refer to new_method.
+bool ConstantPoolCacheEntry::adjust_method_entry(methodOop old_method,
+       methodOop new_method, bool * trace_name_printed) {
+
+  if (is_vfinal()) {
+    // virtual and final so f2() contains method ptr instead of vtable index
+    if (f2() == (intptr_t)old_method) {
+      // match old_method so need an update
+      _f2 = (intptr_t)new_method;
+      if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) {
+        if (!(*trace_name_printed)) {
+          // RC_TRACE_MESG macro has an embedded ResourceMark
+          RC_TRACE_MESG(("adjust: name=%s",
+            Klass::cast(old_method->method_holder())->external_name()));
+          *trace_name_printed = true;
+        }
+        // RC_TRACE macro has an embedded ResourceMark
+        RC_TRACE(0x00400000, ("cpc vf-entry update: %s(%s)",
+          new_method->name()->as_C_string(),
+          new_method->signature()->as_C_string()));
+      }
+
+      return true;
+    }
+
+    // f1() is not used with virtual entries so bail out
+    return false;
+  }
+
+  if ((oop)_f1 == NULL) {
+    // NULL f1() means this is a virtual entry so bail out
+    // We are assuming that the vtable index does not need change.
+    return false;
+  }
+
+  if ((oop)_f1 == old_method) {
+    _f1 = new_method;
+    if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) {
+      if (!(*trace_name_printed)) {
+        // RC_TRACE_MESG macro has an embedded ResourceMark
+        RC_TRACE_MESG(("adjust: name=%s",
+          Klass::cast(old_method->method_holder())->external_name()));
+        *trace_name_printed = true;
+      }
+      // RC_TRACE macro has an embedded ResourceMark
+      RC_TRACE(0x00400000, ("cpc entry update: %s(%s)",
+        new_method->name()->as_C_string(),
+        new_method->signature()->as_C_string()));
+    }
+
+    return true;
+  }
+
+  return false;
+}
+
+bool ConstantPoolCacheEntry::is_interesting_method_entry(klassOop k) {
+  if (!is_method_entry()) {
+    // not a method entry so not interesting by default
+    return false;
+  }
+
+  methodOop m = NULL;
+  if (is_vfinal()) {
+    // virtual and final so _f2 contains method ptr instead of vtable index
+    m = (methodOop)_f2;
+  } else if ((oop)_f1 == NULL) {
+    // NULL _f1 means this is a virtual entry so also not interesting
+    return false;
+  } else {
+    if (!((oop)_f1)->is_method()) {
+      // _f1 can also contain a klassOop for an interface
+      return false;
+    }
+    m = (methodOop)_f1;
+  }
+
+  assert(m != NULL && m->is_method(), "sanity check");
+  if (m == NULL || !m->is_method() || m->method_holder() != k) {
+    // robustness for above sanity checks or method is not in
+    // the interesting class
+    return false;
+  }
+
+  // the method is in the interesting class so the entry is interesting
+  return true;
+}
+
+void ConstantPoolCacheEntry::print(outputStream* st, int index) const {
+  // print separator
+  if (index == 0) tty->print_cr("                 -------------");
+  // print entry
+  tty->print_cr("%3d  (%08x)  [%02x|%02x|%5d]", index, this, bytecode_2(), bytecode_1(), constant_pool_index());
+  tty->print_cr("                 [   %08x]", (address)(oop)_f1);
+  tty->print_cr("                 [   %08x]", _f2);
+  tty->print_cr("                 [   %08x]", _flags);
+  tty->print_cr("                 -------------");
+}
+
+void ConstantPoolCacheEntry::verify(outputStream* st) const {
+  // not implemented yet
+}
+
+// Implementation of ConstantPoolCache
+
+void constantPoolCacheOopDesc::initialize(intArray& inverse_index_map) {
+  assert(inverse_index_map.length() == length(), "inverse index map must have same length as cache");
+  for (int i = 0; i < length(); i++) entry_at(i)->set_initial_state(inverse_index_map[i]);
+}
+
+// RedefineClasses() API support:
+// If any entry of this constantPoolCache points to any of
+// old_methods, replace it with the corresponding new_method.
+void constantPoolCacheOopDesc::adjust_method_entries(methodOop* old_methods, methodOop* new_methods,
+                                                     int methods_length, bool * trace_name_printed) {
+
+  if (methods_length == 0) {
+    // nothing to do if there are no methods
+    return;
+  }
+
+  // get shorthand for the interesting class
+  klassOop old_holder = old_methods[0]->method_holder();
+
+  for (int i = 0; i < length(); i++) {
+    if (!entry_at(i)->is_interesting_method_entry(old_holder)) {
+      // skip uninteresting methods
+      continue;
+    }
+
+    // The constantPoolCache contains entries for several different
+    // things, but we only care about methods. In fact, we only care
+    // about methods in the same class as the one that contains the
+    // old_methods. At this point, we have an interesting entry.
+
+    for (int j = 0; j < methods_length; j++) {
+      methodOop old_method = old_methods[j];
+      methodOop new_method = new_methods[j];
+
+      if (entry_at(i)->adjust_method_entry(old_method, new_method,
+          trace_name_printed)) {
+        // current old_method matched this entry and we updated it so
+        // break out and get to the next interesting entry if there one
+        break;
+      }
+    }
+  }
+}