hotspot/src/share/vm/compiler/oopMap.cpp
changeset 1 489c9b5090e2
child 198 8601165a33c3
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/compiler/oopMap.cpp	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,662 @@
+/*
+ * Copyright 1998-2007 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/_oopMap.cpp.incl"
+
+// OopMapStream
+
+OopMapStream::OopMapStream(OopMap* oop_map) {
+  if(oop_map->omv_data() == NULL) {
+    _stream = new CompressedReadStream(oop_map->write_stream()->buffer());
+  } else {
+    _stream = new CompressedReadStream(oop_map->omv_data());
+  }
+  _mask = OopMapValue::type_mask_in_place;
+  _size = oop_map->omv_count();
+  _position = 0;
+  _valid_omv = false;
+}
+
+
+OopMapStream::OopMapStream(OopMap* oop_map, int oop_types_mask) {
+  if(oop_map->omv_data() == NULL) {
+    _stream = new CompressedReadStream(oop_map->write_stream()->buffer());
+  } else {
+    _stream = new CompressedReadStream(oop_map->omv_data());
+  }
+  _mask = oop_types_mask;
+  _size = oop_map->omv_count();
+  _position = 0;
+  _valid_omv = false;
+}
+
+
+void OopMapStream::find_next() {
+  while(_position++ < _size) {
+    _omv.read_from(_stream);
+    if(((int)_omv.type() & _mask) > 0) {
+      _valid_omv = true;
+      return;
+    }
+  }
+  _valid_omv = false;
+}
+
+
+// OopMap
+
+// frame_size units are stack-slots (4 bytes) NOT intptr_t; we can name odd
+// slots to hold 4-byte values like ints and floats in the LP64 build.
+OopMap::OopMap(int frame_size, int arg_count) {
+  // OopMaps are usually quite so small, so pick a small initial size
+  set_write_stream(new CompressedWriteStream(32));
+  set_omv_data(NULL);
+  set_omv_count(0);
+
+#ifdef ASSERT
+  _locs_length = VMRegImpl::stack2reg(0)->value() + frame_size + arg_count;
+  _locs_used   = NEW_RESOURCE_ARRAY(OopMapValue::oop_types, _locs_length);
+  for(int i = 0; i < _locs_length; i++) _locs_used[i] = OopMapValue::unused_value;
+#endif
+}
+
+
+OopMap::OopMap(OopMap::DeepCopyToken, OopMap* source) {
+  // This constructor does a deep copy
+  // of the source OopMap.
+  set_write_stream(new CompressedWriteStream(source->omv_count() * 2));
+  set_omv_data(NULL);
+  set_omv_count(0);
+  set_offset(source->offset());
+
+#ifdef ASSERT
+  _locs_length = source->_locs_length;
+  _locs_used = NEW_RESOURCE_ARRAY(OopMapValue::oop_types, _locs_length);
+  for(int i = 0; i < _locs_length; i++) _locs_used[i] = OopMapValue::unused_value;
+#endif
+
+  // We need to copy the entries too.
+  for (OopMapStream oms(source); !oms.is_done(); oms.next()) {
+    OopMapValue omv = oms.current();
+    omv.write_on(write_stream());
+    increment_count();
+  }
+}
+
+
+OopMap* OopMap::deep_copy() {
+  return new OopMap(_deep_copy_token, this);
+}
+
+
+void OopMap::copy_to(address addr) {
+  memcpy(addr,this,sizeof(OopMap));
+  memcpy(addr + sizeof(OopMap),write_stream()->buffer(),write_stream()->position());
+  OopMap* new_oop = (OopMap*)addr;
+  new_oop->set_omv_data_size(write_stream()->position());
+  new_oop->set_omv_data((unsigned char *)(addr + sizeof(OopMap)));
+  new_oop->set_write_stream(NULL);
+}
+
+
+int OopMap::heap_size() const {
+  int size = sizeof(OopMap);
+  int align = sizeof(void *) - 1;
+  if(write_stream() != NULL) {
+    size += write_stream()->position();
+  } else {
+    size += omv_data_size();
+  }
+  // Align to a reasonable ending point
+  size = ((size+align) & ~align);
+  return size;
+}
+
+// frame_size units are stack-slots (4 bytes) NOT intptr_t; we can name odd
+// slots to hold 4-byte values like ints and floats in the LP64 build.
+void OopMap::set_xxx(VMReg reg, OopMapValue::oop_types x, VMReg optional) {
+
+  assert(reg->value() < _locs_length, "too big reg value for stack size");
+  assert( _locs_used[reg->value()] == OopMapValue::unused_value, "cannot insert twice" );
+  debug_only( _locs_used[reg->value()] = x; )
+
+  OopMapValue o(reg, x);
+
+  if(x == OopMapValue::callee_saved_value) {
+    // This can never be a stack location, so we don't need to transform it.
+    assert(optional->is_reg(), "Trying to callee save a stack location");
+    o.set_content_reg(optional);
+  } else if(x == OopMapValue::derived_oop_value) {
+    o.set_content_reg(optional);
+  }
+
+  o.write_on(write_stream());
+  increment_count();
+}
+
+
+void OopMap::set_oop(VMReg reg) {
+  set_xxx(reg, OopMapValue::oop_value, VMRegImpl::Bad());
+}
+
+
+void OopMap::set_value(VMReg reg) {
+  // At this time, we only need value entries in our OopMap when ZapDeadCompiledLocals is active.
+  if (ZapDeadCompiledLocals)
+    set_xxx(reg, OopMapValue::value_value, VMRegImpl::Bad());
+}
+
+
+void OopMap::set_dead(VMReg reg) {
+  // At this time, we only need dead entries in our OopMap when ZapDeadCompiledLocals is active.
+  if (ZapDeadCompiledLocals) {
+    set_xxx(reg, OopMapValue::dead_value, VMRegImpl::Bad());
+  }
+}
+
+
+void OopMap::set_callee_saved(VMReg reg, VMReg caller_machine_register ) {
+  set_xxx(reg, OopMapValue::callee_saved_value, caller_machine_register);
+}
+
+
+void OopMap::set_derived_oop(VMReg reg, VMReg derived_from_local_register ) {
+  if( reg == derived_from_local_register ) {
+    // Actually an oop, derived shares storage with base,
+    set_oop(reg);
+  } else {
+    set_xxx(reg, OopMapValue::derived_oop_value, derived_from_local_register);
+  }
+}
+
+void OopMap::set_stack_obj(VMReg reg) {
+  set_xxx(reg, OopMapValue::stack_obj, VMRegImpl::Bad());
+}
+
+// OopMapSet
+
+OopMapSet::OopMapSet() {
+  set_om_size(MinOopMapAllocation);
+  set_om_count(0);
+  OopMap** temp = NEW_RESOURCE_ARRAY(OopMap*, om_size());
+  set_om_data(temp);
+}
+
+
+void OopMapSet::grow_om_data() {
+  int new_size = om_size() * 2;
+  OopMap** new_data = NEW_RESOURCE_ARRAY(OopMap*, new_size);
+  memcpy(new_data,om_data(),om_size() * sizeof(OopMap*));
+  set_om_size(new_size);
+  set_om_data(new_data);
+}
+
+
+void OopMapSet::copy_to(address addr) {
+  address temp = addr;
+  int align = sizeof(void *) - 1;
+  // Copy this
+  memcpy(addr,this,sizeof(OopMapSet));
+  temp += sizeof(OopMapSet);
+  temp = (address)((intptr_t)(temp + align) & ~align);
+  // Do the needed fixups to the new OopMapSet
+  OopMapSet* new_set = (OopMapSet*)addr;
+  new_set->set_om_data((OopMap**)temp);
+  // Allow enough space for the OopMap pointers
+  temp += (om_count() * sizeof(OopMap*));
+
+  for(int i=0; i < om_count(); i++) {
+    OopMap* map = at(i);
+    map->copy_to((address)temp);
+    new_set->set(i,(OopMap*)temp);
+    temp += map->heap_size();
+  }
+  // This "locks" the OopMapSet
+  new_set->set_om_size(-1);
+}
+
+
+void OopMapSet::add_gc_map(int pc_offset, OopMap *map ) {
+  assert(om_size() != -1,"Cannot grow a fixed OopMapSet");
+
+  if(om_count() >= om_size()) {
+    grow_om_data();
+  }
+  map->set_offset(pc_offset);
+
+#ifdef ASSERT
+  if(om_count() > 0) {
+    OopMap* last = at(om_count()-1);
+    if (last->offset() == map->offset() ) {
+      fatal("OopMap inserted twice");
+    }
+    if(last->offset() > map->offset()) {
+      tty->print_cr( "WARNING, maps not sorted: pc[%d]=%d, pc[%d]=%d",
+                      om_count(),last->offset(),om_count()+1,map->offset());
+    }
+  }
+#endif // ASSERT
+
+  set(om_count(),map);
+  increment_count();
+}
+
+
+int OopMapSet::heap_size() const {
+  // The space we use
+  int size = sizeof(OopMap);
+  int align = sizeof(void *) - 1;
+  size = ((size+align) & ~align);
+  size += om_count() * sizeof(OopMap*);
+
+  // Now add in the space needed for the indivdiual OopMaps
+  for(int i=0; i < om_count(); i++) {
+    size += at(i)->heap_size();
+  }
+  // We don't need to align this, it will be naturally pointer aligned
+  return size;
+}
+
+
+OopMap* OopMapSet::singular_oop_map() {
+  guarantee(om_count() == 1, "Make sure we only have a single gc point");
+  return at(0);
+}
+
+
+OopMap* OopMapSet::find_map_at_offset(int pc_offset) const {
+  int i, len = om_count();
+  assert( len > 0, "must have pointer maps" );
+
+  // Scan through oopmaps. Stop when current offset is either equal or greater
+  // than the one we are looking for.
+  for( i = 0; i < len; i++) {
+    if( at(i)->offset() >= pc_offset )
+      break;
+  }
+
+  assert( i < len, "oopmap not found" );
+
+  OopMap* m = at(i);
+  assert( m->offset() == pc_offset, "oopmap not found" );
+  return m;
+}
+
+class DoNothingClosure: public OopClosure {
+public: void do_oop(oop* p) {}
+};
+static DoNothingClosure do_nothing;
+
+static void add_derived_oop(oop* base, oop* derived) {
+#ifndef TIERED
+  COMPILER1_PRESENT(ShouldNotReachHere();)
+#endif // TIERED
+#ifdef COMPILER2
+  DerivedPointerTable::add(derived, base);
+#endif // COMPILER2
+}
+
+
+#ifndef PRODUCT
+static void trace_codeblob_maps(const frame *fr, const RegisterMap *reg_map) {
+  // Print oopmap and regmap
+  tty->print_cr("------ ");
+  CodeBlob* cb = fr->cb();
+  OopMapSet* maps = cb->oop_maps();
+  OopMap* map = cb->oop_map_for_return_address(fr->pc());
+  map->print();
+  if( cb->is_nmethod() ) {
+    nmethod* nm = (nmethod*)cb;
+    // native wrappers have no scope data, it is implied
+    if (nm->is_native_method()) {
+      tty->print("bci: 0 (native)");
+    } else {
+      ScopeDesc* scope  = nm->scope_desc_at(fr->pc());
+      tty->print("bci: %d ",scope->bci());
+    }
+  }
+  tty->cr();
+  fr->print_on(tty);
+  tty->print("     ");
+  cb->print_value_on(tty);  tty->cr();
+  reg_map->print();
+  tty->print_cr("------ ");
+
+}
+#endif // PRODUCT
+
+void OopMapSet::oops_do(const frame *fr, const RegisterMap* reg_map, OopClosure* f) {
+  // add derived oops to a table
+  all_do(fr, reg_map, f, add_derived_oop, &do_nothing, &do_nothing);
+}
+
+
+void OopMapSet::all_do(const frame *fr, const RegisterMap *reg_map,
+                       OopClosure* oop_fn, void derived_oop_fn(oop*, oop*),
+                       OopClosure* value_fn, OopClosure* dead_fn) {
+  CodeBlob* cb = fr->cb();
+  {
+    assert(cb != NULL, "no codeblob");
+  }
+
+  NOT_PRODUCT(if (TraceCodeBlobStacks) trace_codeblob_maps(fr, reg_map);)
+
+  OopMapSet* maps = cb->oop_maps();
+  OopMap* map  = cb->oop_map_for_return_address(fr->pc());
+  assert(map != NULL, " no ptr map found");
+
+  // handle derived pointers first (otherwise base pointer may be
+  // changed before derived pointer offset has been collected)
+  OopMapValue omv;
+  {
+    OopMapStream oms(map,OopMapValue::derived_oop_value);
+    if (!oms.is_done()) {
+#ifndef TIERED
+      COMPILER1_PRESENT(ShouldNotReachHere();)
+#endif // !TIERED
+      // Protect the operation on the derived pointers.  This
+      // protects the addition of derived pointers to the shared
+      // derived pointer table in DerivedPointerTable::add().
+      MutexLockerEx x(DerivedPointerTableGC_lock, Mutex::_no_safepoint_check_flag);
+      do {
+        omv = oms.current();
+        oop* loc = fr->oopmapreg_to_location(omv.reg(),reg_map);
+        if ( loc != NULL ) {
+          oop *base_loc    = fr->oopmapreg_to_location(omv.content_reg(), reg_map);
+          oop *derived_loc = loc;
+          derived_oop_fn(base_loc, derived_loc);
+        }
+        oms.next();
+      }  while (!oms.is_done());
+    }
+  }
+
+  // We want dead, value and oop oop_types
+  int mask = OopMapValue::oop_value | OopMapValue::value_value | OopMapValue::dead_value;
+  {
+    for (OopMapStream oms(map,mask); !oms.is_done(); oms.next()) {
+      omv = oms.current();
+      oop* loc = fr->oopmapreg_to_location(omv.reg(),reg_map);
+      if ( loc != NULL ) {
+        if ( omv.type() == OopMapValue::oop_value ) {
+#ifdef ASSERT
+          if (COMPILER2_PRESENT(!DoEscapeAnalysis &&) !Universe::heap()->is_in_or_null(*loc)) {
+            tty->print_cr("# Found non oop pointer.  Dumping state at failure");
+            // try to dump out some helpful debugging information
+            trace_codeblob_maps(fr, reg_map);
+            omv.print();
+            tty->print_cr("loc = %p *loc = %p\n", loc, (address)*loc);
+            // do the real assert.
+            assert(Universe::heap()->is_in_or_null(*loc), "found non oop pointer");
+          }
+#endif // ASSERT
+          oop_fn->do_oop(loc);
+        } else if ( omv.type() == OopMapValue::value_value ) {
+          value_fn->do_oop(loc);
+        } else if ( omv.type() == OopMapValue::dead_value ) {
+          dead_fn->do_oop(loc);
+        }
+      }
+    }
+  }
+
+#ifdef COMPILER2
+  if (DoEscapeAnalysis) {
+    for (OopMapStream oms(map, OopMapValue::stack_obj); !oms.is_done(); oms.next()) {
+      omv = oms.current();
+      assert(omv.is_stack_loc(), "should refer to stack location");
+      oop loc = (oop) fr->oopmapreg_to_location(omv.reg(),reg_map);
+      oop_fn->do_oop(&loc);
+    }
+  }
+#endif // COMPILER2
+}
+
+
+// Update callee-saved register info for the following frame
+void OopMapSet::update_register_map(const frame *fr, RegisterMap *reg_map) {
+  ResourceMark rm;
+  CodeBlob* cb = fr->cb();
+  assert(cb != NULL, "no codeblob");
+
+  // Any reg might be saved by a safepoint handler (see generate_handler_blob).
+  const int max_saved_on_entry_reg_count = ConcreteRegisterImpl::number_of_registers;
+  assert( reg_map->_update_for_id == NULL || fr->is_older(reg_map->_update_for_id),
+         "already updated this map; do not 'update' it twice!" );
+  debug_only(reg_map->_update_for_id = fr->id());
+
+  // Check if caller must update oop argument
+  assert((reg_map->include_argument_oops() ||
+          !cb->caller_must_gc_arguments(reg_map->thread())),
+         "include_argument_oops should already be set");
+
+  int nof_callee = 0;
+  oop*        locs[2*max_saved_on_entry_reg_count+1];
+  VMReg regs[2*max_saved_on_entry_reg_count+1];
+  // ("+1" because max_saved_on_entry_reg_count might be zero)
+
+  // Scan through oopmap and find location of all callee-saved registers
+  // (we do not do update in place, since info could be overwritten)
+
+  address pc = fr->pc();
+
+  OopMap* map  = cb->oop_map_for_return_address(pc);
+
+  assert(map != NULL, " no ptr map found");
+
+  OopMapValue omv;
+  for(OopMapStream oms(map,OopMapValue::callee_saved_value); !oms.is_done(); oms.next()) {
+    omv = oms.current();
+    assert(nof_callee < 2*max_saved_on_entry_reg_count, "overflow");
+    regs[nof_callee] = omv.content_reg();
+    locs[nof_callee] = fr->oopmapreg_to_location(omv.reg(),reg_map);
+    nof_callee++;
+  }
+
+  // Check that runtime stubs save all callee-saved registers
+#ifdef COMPILER2
+  assert(cb->is_compiled_by_c1() || !cb->is_runtime_stub() ||
+         (nof_callee >= SAVED_ON_ENTRY_REG_COUNT || nof_callee >= C_SAVED_ON_ENTRY_REG_COUNT),
+         "must save all");
+#endif // COMPILER2
+
+  // Copy found callee-saved register to reg_map
+  for(int i = 0; i < nof_callee; i++) {
+    reg_map->set_location(regs[i], (address)locs[i]);
+  }
+}
+
+//=============================================================================
+// Non-Product code
+
+#ifndef PRODUCT
+
+bool OopMap::has_derived_pointer() const {
+#ifndef TIERED
+  COMPILER1_PRESENT(return false);
+#endif // !TIERED
+#ifdef COMPILER2
+  OopMapStream oms((OopMap*)this,OopMapValue::derived_oop_value);
+  return oms.is_done();
+#else
+  return false;
+#endif // COMPILER2
+}
+
+
+void print_register_type(OopMapValue::oop_types x, VMReg optional) {
+  switch( x ) {
+  case OopMapValue::oop_value:
+    tty->print("Oop");
+    break;
+  case OopMapValue::value_value:
+    tty->print("Value" );
+    break;
+  case OopMapValue::dead_value:
+    tty->print("Dead" );
+    break;
+  case OopMapValue::callee_saved_value:
+    tty->print("Callers_" );
+    optional->print();
+    break;
+  case OopMapValue::derived_oop_value:
+    tty->print("Derived_oop_" );
+    optional->print();
+    break;
+  case OopMapValue::stack_obj:
+    tty->print("Stack");
+    break;
+  default:
+    ShouldNotReachHere();
+  }
+}
+
+
+void OopMapValue::print() const {
+  reg()->print();
+  tty->print("=");
+  print_register_type(type(),content_reg());
+  tty->print(" ");
+}
+
+
+void OopMap::print_on(outputStream* st) const {
+  OopMapValue omv;
+  for(OopMapStream oms((OopMap*)this); !oms.is_done(); oms.next()) {
+    omv = oms.current();
+    omv.print_on(st);
+  }
+}
+
+
+void OopMapSet::print_on(outputStream* st) const {
+  int i, len = om_count();
+
+  st->print_cr("OopMapSet contains %d OopMaps\n",len);
+
+  for( i = 0; i < len; i++) {
+    OopMap* m = at(i);
+    st->print_cr("OopMap #%d offset:%p",i,m->offset());
+    m->print_on(st);
+    st->print_cr("\n");
+  }
+}
+#endif // !PRODUCT
+
+
+//------------------------------DerivedPointerTable---------------------------
+
+#ifdef COMPILER2
+
+class DerivedPointerEntry : public CHeapObj {
+ private:
+  oop*     _location; // Location of derived pointer (also pointing to the base)
+  intptr_t _offset;   // Offset from base pointer
+ public:
+  DerivedPointerEntry(oop* location, intptr_t offset) { _location = location; _offset = offset; }
+  oop* location()    { return _location; }
+  intptr_t  offset() { return _offset; }
+};
+
+
+GrowableArray<DerivedPointerEntry*>* DerivedPointerTable::_list = NULL;
+bool DerivedPointerTable::_active = false;
+
+
+void DerivedPointerTable::clear() {
+  // The first time, we create the list.  Otherwise it should be
+  // empty.  If not, then we have probably forgotton to call
+  // update_pointers after last GC/Scavenge.
+  assert (!_active, "should not be active");
+  assert(_list == NULL || _list->length() == 0, "table not empty");
+  if (_list == NULL) {
+    _list = new (ResourceObj::C_HEAP) GrowableArray<DerivedPointerEntry*>(10, true); // Allocated on C heap
+  }
+  _active = true;
+}
+
+
+// Returns value of location as an int
+intptr_t value_of_loc(oop *pointer) { return (intptr_t)(*pointer); }
+
+
+void DerivedPointerTable::add(oop *derived_loc, oop *base_loc) {
+  assert(Universe::heap()->is_in_or_null(*base_loc), "not an oop");
+  assert(derived_loc != base_loc, "Base and derived in same location");
+  if (_active) {
+    assert(*derived_loc != (oop)base_loc, "location already added");
+    assert(_list != NULL, "list must exist");
+    intptr_t offset = value_of_loc(derived_loc) - value_of_loc(base_loc);
+    assert(offset >= -1000000, "wrong derived pointer info");
+
+    if (TraceDerivedPointers) {
+      tty->print_cr(
+        "Add derived pointer@" INTPTR_FORMAT
+        " - Derived: " INTPTR_FORMAT
+        " Base: " INTPTR_FORMAT " (@" INTPTR_FORMAT ") (Offset: %d)",
+        derived_loc, (address)*derived_loc, (address)*base_loc, base_loc, offset
+      );
+    }
+    // Set derived oop location to point to base.
+    *derived_loc = (oop)base_loc;
+    assert_lock_strong(DerivedPointerTableGC_lock);
+    DerivedPointerEntry *entry = new DerivedPointerEntry(derived_loc, offset);
+    _list->append(entry);
+  }
+}
+
+
+void DerivedPointerTable::update_pointers() {
+  assert(_list != NULL, "list must exist");
+  for(int i = 0; i < _list->length(); i++) {
+    DerivedPointerEntry* entry = _list->at(i);
+    oop* derived_loc = entry->location();
+    intptr_t offset  = entry->offset();
+    // The derived oop was setup to point to location of base
+    oop  base        = **(oop**)derived_loc;
+    assert(Universe::heap()->is_in_or_null(base), "must be an oop");
+
+    *derived_loc = (oop)(((address)base) + offset);
+    assert(value_of_loc(derived_loc) - value_of_loc(&base) == offset, "sanity check");
+
+    if (TraceDerivedPointers) {
+      tty->print_cr("Updating derived pointer@" INTPTR_FORMAT
+                    " - Derived: " INTPTR_FORMAT "  Base: " INTPTR_FORMAT " (Offset: %d)",
+          derived_loc, (address)*derived_loc, (address)base, offset);
+    }
+
+    // Delete entry
+    delete entry;
+    _list->at_put(i, NULL);
+  }
+  // Clear list, so it is ready for next traversal (this is an invariant)
+  if (TraceDerivedPointers && !_list->is_empty()) {
+    tty->print_cr("--------------------------");
+  }
+  _list->clear();
+  _active = false;
+}
+
+#endif // COMPILER2