Summary: ported HotSpot interfaces to Dragonwell8 to support MultiTenant framework

Test Plan: jdk/test/multi-tenant

Reviewed-by: yuleil, sanhong

Issue: https://github.com/alibaba/dragonwell8/issues/84

Summary: add support for opto object allocations sampling

Test Plan: test/jfr/event/objectsprofiling/TestOptoObjectAllocationsSampling.java

Reviewers: zhengxiaolinX, luchsh, sanhong

Issue: https://github.com/alibaba/dragonwell8/issues/64

Summary: G1ElasticHeap to support heap shrink/expansion in runtime

Test Plan:
test/elastic-heap/

Reviewers:

Issue:
https://github.com/alibaba/dragonwell8/issues/46

CR:
https://github.com/alibaba/dragonwell8_hotspot/pull/12

Test Plan: existing test cases

Reviewed-by: shiyue, kuaiwei

Issue: https://github.com/alibaba/dragonwell8/issues/52

Summary: add compatibility for UnlockCommercialFeatures

Test Plan: test/jfr/test_unlockCommercialFeatures_compatibility.sh

Reviewed-by: yfxhust, luchsh

Issue: https://github.com/alibaba/dragonwell8_hotspot/issues/6

Summary:
  Port jwarmup to dragonwell 8u hotspot

ref T19299187

Test Plan:
test/hotspot/jtreg/jwarmup/Issue11272598.java
test/hotspot/jtreg/jwarmup/TestDisableNCE.java
test/hotspot/jtreg/jwarmup/TestNotDeoptJITMethod.sh
test/hotspot/jtreg/jwarmup/issue9780156.sh
test/hotspot/jtreg/jwarmup/TestEagerCompilation.java
test/hotspot/jtreg/jwarmup/TestNotifyDeopt.sh
test/hotspot/jtreg/jwarmup/TestCheckIfCompilationIsComplete.sh
test/hotspot/jtreg/jwarmup/TestFlagAssertion.java
test/hotspot/jtreg/jwarmup/TestReadLogfile.java
test/hotspot/jtreg/jwarmup/TestClassInitChain.java
test/hotspot/jtreg/jwarmup/TestLogFlush.java
test/hotspot/jtreg/jwarmup/TestRecordNullMethodCounter.java
test/hotspot/jtreg/jwarmup/TestThrowInitializaitonException.java
test/hotspot/jtreg/jwarmup/TestDisableMethodData.sh
test/hotspot/jtreg/jwarmup/TestMethodRecorder.java
test/hotspot/jtreg/jwarmup/TestTieredCompilationInRecording.sh

Reviewers: 传胜, 三红, yumin.qi

Reviewed By: 传胜, 三红

Subscribers: 麦庶

Differential Revision: https://aone.alibaba-inc.com/code/D852146

Summary:
- add a warning of large array allocation
- port D3674 to dragonwell

Test Plan: test/runtime/memory/TestArrayAllocationWarning.java

Reviewers: 传胜

Differential Revision: https://aone.alibaba-inc.com/code/D851704

Summary:
- port D64010 to dragonwell
- print the detail time when doing root processing in generational heap collection

Test Plan:
hotspot/test/gc/TestPrintGCRootsTraceTime.java
hotspot/test/gc/

Reviewers: 传胜

Differential Revision: https://aone.alibaba-inc.com/code/D851700

Summary:
- Port D65580 to dragonwell
- Print the young generation histogram once after parnew gc with the manageable flag: PrintYoungGenHistoAfterParNewGC

Test Plan: hotspot/test/gc/parNew/testPrintYoungGenHisto.sh

Reviewers: 传胜

Differential Revision: https://aone.alibaba-inc.com/code/D849729

Summary:
- port D1840 to Dragonwell
- add AJVM_FLAGS extension flag

Test Plan: the other patches which add new VM flags will definitely cover this code change

Reviewers: 传胜

Differential Revision: https://aone.alibaba-inc.com/code/D849610

Summary:
- Port fix D2553 to Dragonwell
- Change default GC policy to UseConcMarkSweepGC

Test Plan: hotspot/test/gc/TestDefaultGC.sh

Reviewers: 井桐

Reviewed By: 井桐

Subscribers:

Differential Revision: https://aone.alibaba-inc.com/code/D849276

Reviewers: 效山, 芳玺, 传胜, 三红, yumin.qi

Reviewed By: 三红, 芳玺, 效山, 卓仁

Differential Revision: https://aone.alibaba-inc.com/code/D815657

8155951: VM crash in nsk/jvmti/RedefineClasses/StressRedefine: assert failed: Corrupted constant pool
8151066: assert(0 <= i && i < length()) failed: index out of bounds
Summary: lock classes for redefinition because constant pool merging isn't thread safe, use method constant pool because constant pool merging doesn't make equivalent cpCaches because of invokedynamic
Reviewed-by: shade, andrew

Summary: Prepare Zero build for backport of JDK-8062808.
Reviewed-by: sgehwolf

Summary: increase code_size2 for stubs
Reviewed-by: iveresov

Summary: Prevent downgraded compilation tasks from recompiling.
Reviewed-by: sgehwolf, thartmann, andrew

Summary: Summary: os::readdir uses POSIX readdir, drop buffer arg, fix JFR uses.
Reviewed-by: coleenp, tschatzl, bsrbnd, shade, phh

Summary: implement os::set_native_thread_name() on windows, linux
Reviewed-by: sla, ctornqvi, simonis
Contributed-by: thomas.stuefe@sap.com

Summary: Add tag bit to all JNI weak handles
Reviewed-by: kbarrett, coleenp, tschatzl

Reviewed-by: tbell, asaha

Reviewed-by: erikj, dholmes

Summary: Introduce alignment-safe Copy::conjoint_swap and JVM_CopySwapMemory
Reviewed-by: mikael, dholmes

Summary: Backport from JDK9
Reviewed-by: dholmes, coffeys

Reviewed-by: acorn, coleenp, kvn, vlivanov

Reviewed-by: tschatzl

Reviewed-by: dholmes

Reviewed-by: dholmes

Reviewed-by: bobv, dbuck

Reviewed-by: bobv, dbuck

8164480: Crash with assert(handler_address == SharedRuntime::compute_compiled_exc_handler(..) failed: Must be the same
Summary: Exception checking code needs to handle pre-allocated exceptions.
Reviewed-by: thartmann, kvn

Reviewed-by: dholmes

Reviewed-by: jrose, coleenp, ahgross, acorn, vlivanov

Summary: Bias compiler thread's resource area to mtCompiler
Reviewed-by: kvn, coleenp

Summary: Set UseLoopCounter ergonomically if on-stack-replacement is enabled. Print warning.
Reviewed-by: kvn

6651256: jstack: DeleteGlobalRef method call doesn't lead to descreasing of global refs count shown by jstack
Summary: jni_DeleteGlobalRef does not really release the jni handle, instead, set the handle point to JNIHandles::_deleted_handle which holds an oop instance (java/lang/Object) in Java heap and never be GC'ed. When counting number of global reference, it counts all the handles on the chain list, which includes the already deleted ones.
Reviewed-by: zgu, sla, coleenp
Contributed-by: yumin.qi@oracle.com

Reviewed-by: kvn, dholmes, bobv

Reviewed-by: kvn, dholmes, bobv

Summary: The GetOwnedMonitorInfo() should not return a pending monitor
Reviewed-by: dcubed

Summary: Fixed missing null checks on the result of CodeCache::find_blob() found by Parfait.
Reviewed-by: shade, kvn

Summary: Make appending found dead BasicHashtableEntrys to the free list atomic.
Reviewed-by: ehelin, shade