Mercurial > hg > truffle
changeset 4737:75c0a73eee98
7102776: Pack instanceKlass boolean fields into single u1 field
Summary: Reduce class runtime memory usage by packing 4 instanceKlass boolean fields into single u1 field. Save 4-byte for each loaded class.
Reviewed-by: dholmes, bobv, phh, twisti, never, coleenp
Contributed-by: Jiangli Zhou <jiangli.zhou@oracle.com>
| author | coleenp |
|---|---|
| date | Thu, 17 Nov 2011 12:53:59 -0500 |
| parents | 869804b759e7 |
| children | da4dd142ea01 |
| files | agent/src/share/classes/sun/jvm/hotspot/oops/InstanceKlass.java src/share/vm/code/dependencies.cpp src/share/vm/oops/instanceKlass.hpp src/share/vm/oops/instanceKlassKlass.cpp src/share/vm/runtime/vmStructs.cpp |
| diffstat | 5 files changed, 50 insertions(+), 20 deletions(-) [+] |
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--- a/agent/src/share/classes/sun/jvm/hotspot/oops/InstanceKlass.java Fri Nov 04 14:06:09 2011 -0700 +++ b/agent/src/share/classes/sun/jvm/hotspot/oops/InstanceKlass.java Thu Nov 17 12:53:59 2011 -0500 @@ -63,6 +63,8 @@ private static int CLASS_STATE_FULLY_INITIALIZED; private static int CLASS_STATE_INITIALIZATION_ERROR; + private static int IS_MARKED_DEPENDENT_MASK; + private static synchronized void initialize(TypeDataBase db) throws WrongTypeException { Type type = db.lookupType("instanceKlass"); arrayKlasses = new OopField(type.getOopField("_array_klasses"), Oop.getHeaderSize()); @@ -90,7 +92,7 @@ staticFieldSize = new CIntField(type.getCIntegerField("_static_field_size"), Oop.getHeaderSize()); staticOopFieldCount = new CIntField(type.getCIntegerField("_static_oop_field_count"), Oop.getHeaderSize()); nonstaticOopMapSize = new CIntField(type.getCIntegerField("_nonstatic_oop_map_size"), Oop.getHeaderSize()); - isMarkedDependent = new CIntField(type.getCIntegerField("_is_marked_dependent"), Oop.getHeaderSize()); + miscFlags = new CIntField(type.getCIntegerField("_misc_flags"), Oop.getHeaderSize()); initState = new CIntField(type.getCIntegerField("_init_state"), Oop.getHeaderSize()); vtableLen = new CIntField(type.getCIntegerField("_vtable_len"), Oop.getHeaderSize()); itableLen = new CIntField(type.getCIntegerField("_itable_len"), Oop.getHeaderSize()); @@ -118,6 +120,8 @@ CLASS_STATE_FULLY_INITIALIZED = db.lookupIntConstant("instanceKlass::fully_initialized").intValue(); CLASS_STATE_INITIALIZATION_ERROR = db.lookupIntConstant("instanceKlass::initialization_error").intValue(); + IS_MARKED_DEPENDENT_MASK = db.lookupIntConstant("instanceKlass::IS_MARKED_DEPENDENT").intValue(); + } InstanceKlass(OopHandle handle, ObjectHeap heap) { @@ -151,7 +155,7 @@ private static CIntField staticFieldSize; private static CIntField staticOopFieldCount; private static CIntField nonstaticOopMapSize; - private static CIntField isMarkedDependent; + private static CIntField miscFlags; private static CIntField initState; private static CIntField vtableLen; private static CIntField itableLen; @@ -333,7 +337,7 @@ public long getNonstaticFieldSize() { return nonstaticFieldSize.getValue(this); } public long getStaticOopFieldCount() { return staticOopFieldCount.getValue(this); } public long getNonstaticOopMapSize() { return nonstaticOopMapSize.getValue(this); } - public boolean getIsMarkedDependent() { return isMarkedDependent.getValue(this) != 0; } + public boolean getIsMarkedDependent() { return (miscFlags.getValue(this) & IS_MARKED_DEPENDENT_MASK) != 0; } public long getVtableLen() { return vtableLen.getValue(this); } public long getItableLen() { return itableLen.getValue(this); } public Symbol getGenericSignature() { return getSymbol(genericSignature); } @@ -524,7 +528,7 @@ visitor.doCInt(staticFieldSize, true); visitor.doCInt(staticOopFieldCount, true); visitor.doCInt(nonstaticOopMapSize, true); - visitor.doCInt(isMarkedDependent, true); + visitor.doCInt(miscFlags, true); visitor.doCInt(initState, true); visitor.doCInt(vtableLen, true); visitor.doCInt(itableLen, true);
--- a/src/share/vm/code/dependencies.cpp Fri Nov 04 14:06:09 2011 -0700 +++ b/src/share/vm/code/dependencies.cpp Thu Nov 17 12:53:59 2011 -0500 @@ -1624,7 +1624,7 @@ for (ContextStream str(*this); str.next(); ) { klassOop d = str.klass(); assert(!instanceKlass::cast(d)->is_marked_dependent(), "checking"); - instanceKlass::cast(d)->set_is_marked_dependent(true); + instanceKlass::cast(d)->set_is_marked_dependent(); } } @@ -1633,7 +1633,7 @@ // Unmark transitive interfaces for (ContextStream str(*this); str.next(); ) { klassOop d = str.klass(); - instanceKlass::cast(d)->set_is_marked_dependent(false); + instanceKlass::cast(d)->clear_is_marked_dependent(); } }
--- a/src/share/vm/oops/instanceKlass.hpp Fri Nov 04 14:06:09 2011 -0700 +++ b/src/share/vm/oops/instanceKlass.hpp Thu Nov 17 12:53:59 2011 -0500 @@ -230,10 +230,7 @@ int _static_oop_field_count;// number of static oop fields in this klass int _nonstatic_oop_map_size;// size in words of nonstatic oop map blocks int _java_fields_count; // The number of declared Java fields - bool _is_marked_dependent; // used for marking during flushing and deoptimization - bool _rewritten; // methods rewritten. - bool _has_nonstatic_fields; // for sizing with UseCompressedOops - bool _should_verify_class; // allow caching of preverification + u2 _minor_version; // minor version number of class file u2 _major_version; // major version number of class file ClassState _init_state; // state of class @@ -260,6 +257,19 @@ JvmtiCachedClassFieldMap* _jvmti_cached_class_field_map; // JVMTI: used during heap iteration volatile u2 _idnum_allocated_count; // JNI/JVMTI: increments with the addition of methods, old ids don't change + // Compact the following four boolean flags into 1-bit each. These four flags + // were defined as separate boolean fields and each was 1-byte before. Since + // there are 2 bytes unused after the _idnum_allocated_count field, place the + // _misc_flags field after _idnum_allocated_count to utilize the unused bits + // and save total 4-bytes. + enum { + IS_MARKED_DEPENDENT = 0x1, // used for marking during flushing and deoptimization + REWRITTEN = 0x2, // methods rewritten. + HAS_NONSTATIC_FIELDS = 0x4, // for sizing with UseCompressedOops + SHOULD_VERIFY_CLASS = 0x8 // allow caching of preverification + }; + u1 _misc_flags; + // embedded Java vtable follows here // embedded Java itables follows here // embedded static fields follows here @@ -269,8 +279,14 @@ friend class SystemDictionary; public: - bool has_nonstatic_fields() const { return _has_nonstatic_fields; } - void set_has_nonstatic_fields(bool b) { _has_nonstatic_fields = b; } + bool has_nonstatic_fields() const { return (_misc_flags & HAS_NONSTATIC_FIELDS) != 0; } + void set_has_nonstatic_fields(bool b) { + if (b) { + _misc_flags |= HAS_NONSTATIC_FIELDS; + } else { + _misc_flags &= ~HAS_NONSTATIC_FIELDS; + } + } // field sizes int nonstatic_field_size() const { return _nonstatic_field_size; } @@ -378,15 +394,23 @@ bool is_in_error_state() const { return _init_state == initialization_error; } bool is_reentrant_initialization(Thread *thread) { return thread == _init_thread; } int get_init_state() { return _init_state; } // Useful for debugging - bool is_rewritten() const { return _rewritten; } + bool is_rewritten() const { return (_misc_flags & REWRITTEN) != 0; } // defineClass specified verification - bool should_verify_class() const { return _should_verify_class; } - void set_should_verify_class(bool value) { _should_verify_class = value; } + bool should_verify_class() const { return (_misc_flags & SHOULD_VERIFY_CLASS) != 0; } + void set_should_verify_class(bool value) { + if (value) { + _misc_flags |= SHOULD_VERIFY_CLASS; + } else { + _misc_flags &= ~SHOULD_VERIFY_CLASS; + } + } + // marking - bool is_marked_dependent() const { return _is_marked_dependent; } - void set_is_marked_dependent(bool value) { _is_marked_dependent = value; } + bool is_marked_dependent() const { return (_misc_flags & IS_MARKED_DEPENDENT) != 0; } + void set_is_marked_dependent() { _misc_flags |= IS_MARKED_DEPENDENT; } + void clear_is_marked_dependent() { _misc_flags &= ~IS_MARKED_DEPENDENT; } // initialization (virtuals from Klass) bool should_be_initialized() const; // means that initialize should be called @@ -756,7 +780,7 @@ #else void set_init_state(ClassState state) { _init_state = state; } #endif - void set_rewritten() { _rewritten = true; } + void set_rewritten() { _misc_flags |= REWRITTEN; } void set_init_thread(Thread *thread) { _init_thread = thread; } u2 idnum_allocated_count() const { return _idnum_allocated_count; }
--- a/src/share/vm/oops/instanceKlassKlass.cpp Fri Nov 04 14:06:09 2011 -0700 +++ b/src/share/vm/oops/instanceKlassKlass.cpp Thu Nov 17 12:53:59 2011 -0500 @@ -399,7 +399,7 @@ ik->set_inner_classes(NULL); ik->set_static_oop_field_count(0); ik->set_nonstatic_field_size(0); - ik->set_is_marked_dependent(false); + ik->clear_is_marked_dependent(); ik->set_init_state(instanceKlass::allocated); ik->set_init_thread(NULL); ik->set_reference_type(rt);
--- a/src/share/vm/runtime/vmStructs.cpp Fri Nov 04 14:06:09 2011 -0700 +++ b/src/share/vm/runtime/vmStructs.cpp Thu Nov 17 12:53:59 2011 -0500 @@ -307,7 +307,7 @@ nonstatic_field(instanceKlass, _static_field_size, int) \ nonstatic_field(instanceKlass, _static_oop_field_count, int) \ nonstatic_field(instanceKlass, _nonstatic_oop_map_size, int) \ - nonstatic_field(instanceKlass, _is_marked_dependent, bool) \ + nonstatic_field(instanceKlass, _misc_flags, u1) \ nonstatic_field(instanceKlass, _minor_version, u2) \ nonstatic_field(instanceKlass, _major_version, u2) \ nonstatic_field(instanceKlass, _init_state, instanceKlass::ClassState) \ @@ -1362,6 +1362,7 @@ /* The compiler thinks this is a different type than */ \ /* unsigned short on Win32 */ \ declare_unsigned_integer_type(u2) \ + declare_unsigned_integer_type(u1) \ declare_unsigned_integer_type(unsigned) \ \ /*****************************/ \ @@ -2385,6 +2386,7 @@ declare_constant(instanceKlass::being_initialized) \ declare_constant(instanceKlass::fully_initialized) \ declare_constant(instanceKlass::initialization_error) \ + declare_constant(instanceKlass::IS_MARKED_DEPENDENT) \ \ /*********************************/ \ /* Symbol* - symbol max length */ \