FRWTransactionallySafeAccessDetectorDefinition

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A transactionally safe access detector that works in the following novel ways:

• In the open (non-transactional):
• Acquires the read/write access like before.
• Release the read/write access like before.
• In the closed (transactional):
• During acquiring read access we query `ReadLockCount_:
• 0 means we haven't taken read access before in our transaction nest and we acquire it.
• But only if we haven't previously taken write access (by querying `WriteLockCount_).
• Then we bump `ReadLockCount_ to remember we did a read.
• We also register an on-abort handler to release the access.
• During acquiring write access we query `WriteLockCount_:
• 0 means we haven't taken write access before in our transaction nest and we acquire it.
• But if `ReadLockCount_ was non-zero then we have to upgrade the access from read to write.
• Then we bump `WriteLockCount_ to remember we did a write.
• During releases we defer these to on-commit.

During on-commit we always release all our `ReadLockCount_'s first, so that we handle the case correctly where we had read then write, we need to only actually release the write access and this means we correctly handle that case.

Syntax

struct FRWTransactionallySafeAccessDetectorDefinition  
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struct FRWTransactionallySafeAccessDetectorDefinition

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