JDK-8156068 : Unsafe.{get|set}Opaque should be single copy atomic
- Type: Sub-task
- Component: hotspot
- Sub-Component: compiler
- Priority: P2
- Status: Resolved
- Resolution: Fixed
- Submitted: 2016-05-04
- Updated: 2016-05-26
- Resolved: 2016-05-06
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| JDK 9 |
|---|
9 b120Fixed  |
Description
Current C2 intrinsic code makes Opaque a "relaxed" plain load/store with regards to single copy atomicity.
bool requires_atomic_access = false;
switch (kind) {
case Relaxed:
case Opaque:
requires_atomic_access = AlwaysAtomicAccesses;
break;
This contradicts the intent of making Opaque similar to std::atomic...(..., memory_order_relaxed), which is single copy atomic.