Add field-logging barrier and field unlog bit (JDK21) - #359
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| assert!(!COMPRESSED); | ||
| self.addr |
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I just realized this issue in my branch. I think something like the below is better:
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| assert!(!COMPRESSED); | |
| self.addr | |
| if COMPRESSED { | |
| self.untagged_address() | |
| } else { | |
| self.addr | |
| } |
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I will eventually do this. Currently the 1 bit per word field unlog bit side metadata doesn't work for compressed pointers, so I want it to fail loud. To support compressed pointers, I will introduce an alternative 1 bit per 32 bit field unlog bit side metadata and give the VM binding the option to select that.
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Ah fair enough. Makes sense. I just found this bug in my branch so I thought it'd be better to make a comment here in case you also have issues with the same in the future.
`ObjectBarrier` -> `GenBarrier`. It is related to generational GC, and can be object or field-grained. `UnlogBit` -> `ObjectUnlogBit`. Added `Object` prefix to prepare for adding field unlog bit barriers.
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Upstream PR: mmtk/mmtk-core#1528