truffle: src/share/vm/gc_implementation/g1/g1CollectedHeap.hpp comparison

comparison src/share/vm/gc_implementation/g1/g1CollectedHeap.hpp @ 17759:bc22cbb8b45a

8035330: Remove G1ParScanPartialArrayClosure and G1ParScanHeapEvacClosure Summary: Mentioned closures are actually wrapped methods. This adds confusion to readers, and in this case also increases code size as G1ParScanHeapEvacClosure is part of the oop_oop_iterate() methods. Move them into G1ParScanThreadState as methods. Reviewed-by: stefank

author	tschatzl
date	Mon, 24 Mar 2014 15:30:56 +0100
parents	a07bea31ef35
children	8ee855b4e667

comparison

equal deleted inserted replaced

-:ae7336d6337e
+:bc22cbb8b45a
 size_t           _alloc_buffer_waste;
 size_t           _undo_waste;
 OopsInHeapRegionClosure*      _evac_failure_cl;
-G1ParScanHeapEvacClosure*     _evac_cl;
-G1ParScanPartialArrayClosure* _partial_scan_cl;
 int  _hash_seed;
 uint _queue_num;
 size_t _term_attempts;
 }
 OopsInHeapRegionClosure* evac_failure_closure() {
 return _evac_failure_cl;
 }
-void set_evac_closure(G1ParScanHeapEvacClosure* evac_cl) {
-_evac_cl = evac_cl;
-}
-void set_partial_scan_closure(G1ParScanPartialArrayClosure* partial_scan_cl) {
-_partial_scan_cl = partial_scan_cl;
-}
 int* hash_seed() { return &_hash_seed; }
 uint queue_num() { return _queue_num; }
 size_t term_attempts() const  { return _term_attempts; }
 void note_term_attempt() { _term_attempts++; }
 _alloc_buffers[ap]->flush_stats_and_retire(_g1h->stats_for_purpose((GCAllocPurpose)ap),
 true /* end_of_gc */,
 false /* retain */);
 }
 }
+private:
+#define G1_PARTIAL_ARRAY_MASK 0x2
+inline bool has_partial_array_mask(oop* ref) const {
+return ((uintptr_t)ref & G1_PARTIAL_ARRAY_MASK) == G1_PARTIAL_ARRAY_MASK;
+}
+// We never encode partial array oops as narrowOop*, so return false immediately.
+// This allows the compiler to create optimized code when popping references from
+// the work queue.
+inline bool has_partial_array_mask(narrowOop* ref) const {
+assert(((uintptr_t)ref & G1_PARTIAL_ARRAY_MASK) != G1_PARTIAL_ARRAY_MASK, "Partial array oop reference encoded as narrowOop*");
+return false;
+}
+// Only implement set_partial_array_mask() for regular oops, not for narrowOops.
+// We always encode partial arrays as regular oop, to allow the
+// specialization for has_partial_array_mask() for narrowOops above.
+// This means that unintentional use of this method with narrowOops are caught
+// by the compiler.
+inline oop* set_partial_array_mask(oop obj) const {
+assert(((uintptr_t)(void *)obj & G1_PARTIAL_ARRAY_MASK) == 0, "Information loss!");
+return (oop*) ((uintptr_t)(void *)obj | G1_PARTIAL_ARRAY_MASK);
+}
+inline oop clear_partial_array_mask(oop* ref) const {
+return cast_to_oop((intptr_t)ref & ~G1_PARTIAL_ARRAY_MASK);
+}
+void do_oop_partial_array(oop* p) {
+assert(has_partial_array_mask(p), "invariant");
+oop from_obj = clear_partial_array_mask(p);
+assert(Universe::heap()->is_in_reserved(from_obj), "must be in heap.");
+assert(from_obj->is_objArray(), "must be obj array");
+objArrayOop from_obj_array = objArrayOop(from_obj);
+// The from-space object contains the real length.
+int length                 = from_obj_array->length();
+assert(from_obj->is_forwarded(), "must be forwarded");
+oop to_obj                 = from_obj->forwardee();
+assert(from_obj != to_obj, "should not be chunking self-forwarded objects");
+objArrayOop to_obj_array   = objArrayOop(to_obj);
+// We keep track of the next start index in the length field of the
+// to-space object.
+int next_index             = to_obj_array->length();
+assert(0 <= next_index && next_index < length,
+err_msg("invariant, next index: %d, length: %d", next_index, length));
+int start                  = next_index;
+int end                    = length;
+int remainder              = end - start;
+// We'll try not to push a range that's smaller than ParGCArrayScanChunk.
+if (remainder > 2 * ParGCArrayScanChunk) {
+end = start + ParGCArrayScanChunk;
+to_obj_array->set_length(end);
+// Push the remainder before we process the range in case another
+// worker has run out of things to do and can steal it.
+oop* from_obj_p = set_partial_array_mask(from_obj);
+push_on_queue(from_obj_p);
+} else {
+assert(length == end, "sanity");
+// We'll process the final range for this object. Restore the length
+// so that the heap remains parsable in case of evacuation failure.
+to_obj_array->set_length(end);
+}
+_scanner.set_region(_g1h->heap_region_containing_raw(to_obj));
+// Process indexes [start,end). It will also process the header
+// along with the first chunk (i.e., the chunk with start == 0).
+// Note that at this point the length field of to_obj_array is not
+// correct given that we are using it to keep track of the next
+// start index. oop_iterate_range() (thankfully!) ignores the length
+// field and only relies on the start / end parameters.  It does
+// however return the size of the object which will be incorrect. So
+// we have to ignore it even if we wanted to use it.
+to_obj_array->oop_iterate_range(&_scanner, start, end);
+}
+// This method is applied to the fields of the objects that have just been copied.
+template <class T> void do_oop_evac(T* p, HeapRegion* from) {
+assert(!oopDesc::is_null(oopDesc::load_decode_heap_oop(p)),
+"Reference should not be NULL here as such are never pushed to the task queue.");
+oop obj = oopDesc::load_decode_heap_oop_not_null(p);
+// Although we never intentionally push references outside of the collection
+// set, due to (benign) races in the claim mechanism during RSet scanning more
+// than one thread might claim the same card. So the same card may be
+// processed multiple times. So redo this check.
+if (_g1h->in_cset_fast_test(obj)) {
+oop forwardee;
+if (obj->is_forwarded()) {
+forwardee = obj->forwardee();
+} else {
+forwardee = copy_to_survivor_space(obj);
+}
+assert(forwardee != NULL, "forwardee should not be NULL");
+oopDesc::encode_store_heap_oop(p, forwardee);
+}
+assert(obj != NULL, "Must be");
+update_rs(from, p, queue_num());
+}
+public:
 oop copy_to_survivor_space(oop const obj);
 template <class T> void deal_with_reference(T* ref_to_scan) {
-if (has_partial_array_mask(ref_to_scan)) {
+if (!has_partial_array_mask(ref_to_scan)) {
-_partial_scan_cl->do_oop_nv(ref_to_scan);
-} else {
 // Note: we can use "raw" versions of "region_containing" because
 // "obj_to_scan" is definitely in the heap, and is not in a
 // humongous region.
 HeapRegion* r = _g1h->heap_region_containing_raw(ref_to_scan);
-_evac_cl->set_region(r);
+do_oop_evac(ref_to_scan, r);
-_evac_cl->do_oop_nv(ref_to_scan);
+} else {
+do_oop_partial_array((oop*)ref_to_scan);
 }
 }
 void deal_with_reference(StarTask ref) {
 assert(verify_task(ref), "sanity");

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comparison src/share/vm/gc_implementation/g1/g1CollectedHeap.hpp @ 17759:bc22cbb8b45a