151 oop res_oop = _heap->evacuate_object(obj, thread);
152
153 // Since we are already here and paid the price of getting through runtime call adapters
154 // and acquiring oom-scope, it makes sense to try and evacuate more adjacent objects,
155 // thus amortizing the overhead. For sparsely live heaps, scan costs easily dominate
156 // total assist costs, and can introduce a lot of evacuation latency. This is why we
157 // only scan for _nearest_ N objects, regardless if they are eligible for evac or not.
158 // The scan itself should also avoid touching the non-marked objects below TAMS, because
159 // their metadata (notably, klasses) may be incorrect already.
160
161 size_t max = ShenandoahEvacAssist;
162 if (max > 0) {
163 // Traversal is special: it uses incomplete marking context, because it coalesces evac with mark.
164 // Other code uses complete marking context, because evac happens after the mark.
165 ShenandoahMarkingContext* ctx = _heap->is_concurrent_traversal_in_progress() ?
166 _heap->marking_context() : _heap->complete_marking_context();
167
168 ShenandoahHeapRegion* r = _heap->heap_region_containing(obj);
169 assert(r->is_cset(), "sanity");
170
171 HeapWord* cur = (HeapWord*)obj + obj->size();
172
173 size_t count = 0;
174 while ((cur < r->top()) && ctx->is_marked(oop(cur)) && (count++ < max)) {
175 oop cur_oop = oop(cur);
176 if (cur_oop == resolve_forwarded_not_null(cur_oop)) {
177 _heap->evacuate_object(cur_oop, thread);
178 }
179 cur = cur + cur_oop->size();
180 }
181 }
182
183 fwd = res_oop;
184 }
185
186 if (load_addr != NULL && fwd != obj) {
187 // Since we are here and we know the load address, update the reference.
188 ShenandoahHeap::cas_oop(fwd, load_addr, obj);
189 }
190
191 return fwd;
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151 oop res_oop = _heap->evacuate_object(obj, thread);
152
153 // Since we are already here and paid the price of getting through runtime call adapters
154 // and acquiring oom-scope, it makes sense to try and evacuate more adjacent objects,
155 // thus amortizing the overhead. For sparsely live heaps, scan costs easily dominate
156 // total assist costs, and can introduce a lot of evacuation latency. This is why we
157 // only scan for _nearest_ N objects, regardless if they are eligible for evac or not.
158 // The scan itself should also avoid touching the non-marked objects below TAMS, because
159 // their metadata (notably, klasses) may be incorrect already.
160
161 size_t max = ShenandoahEvacAssist;
162 if (max > 0) {
163 // Traversal is special: it uses incomplete marking context, because it coalesces evac with mark.
164 // Other code uses complete marking context, because evac happens after the mark.
165 ShenandoahMarkingContext* ctx = _heap->is_concurrent_traversal_in_progress() ?
166 _heap->marking_context() : _heap->complete_marking_context();
167
168 ShenandoahHeapRegion* r = _heap->heap_region_containing(obj);
169 assert(r->is_cset(), "sanity");
170
171 HeapWord* cur = cast_from_oop<HeapWord*>(obj) + obj->size();
172
173 size_t count = 0;
174 while ((cur < r->top()) && ctx->is_marked(oop(cur)) && (count++ < max)) {
175 oop cur_oop = oop(cur);
176 if (cur_oop == resolve_forwarded_not_null(cur_oop)) {
177 _heap->evacuate_object(cur_oop, thread);
178 }
179 cur = cur + cur_oop->size();
180 }
181 }
182
183 fwd = res_oop;
184 }
185
186 if (load_addr != NULL && fwd != obj) {
187 // Since we are here and we know the load address, update the reference.
188 ShenandoahHeap::cas_oop(fwd, load_addr, obj);
189 }
190
191 return fwd;
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