5.9: [MoveOnlyAddressChecker] Fix representation for reinit'd fields. #66947
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Used the TypeTreeLeafTypeRange::setBits helper rather than looping over the range and setting the bits in place.
In preparation to share the getOrCreateConsumingBlock functionality with another overload of recordConsumingBlock.
The new overload iterates over the contiguous ranges in the bit vector and calls through to the overload that takes a range.
The address checker records instructions that reinit fields in its reinitInsts map. Previously, that map mapped from an instruction to a range of fields of the type. But an instruction can use multiple discontiguous fields of a single value. (Indeed an attempt to add a second range that was reinit'd by an already reinit'ing instruction--even if it were overlapping or adjacent--would have no effect and the map wouldn't be updated.) Here, this is fixed by fixing the representation and updating the storage whenver a new range is seen to be reinit'd by the instruction. As in swiftlang#66728 , a SmallBitVector is the representation chosen. rdar://111356251
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gottesmm
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Description: Fix a class of miscompiles in the move-only address checker.
The move-only address checker records which instructions reinitialize ranges of fields of a move-only value. Previously, it recorded instructions which reinitialized and the reinitialized fields via a map from instructions to ranges of fields of the value. But a single instruction can reinitialize non-contiguous fields of the value being checked.
The fix is to change the the value stored corresponding to an instruction to have enough information to store all the non-contiguous fields of the value that it uses. Here, the representation of a bit vector is implemented.
Risk: Low. The change is straightforward and similar in spirit to #66738 .
Scope: Narrow. This only affects move-only types.
Original PR: #66945
Reviewed By: Andrew Trick ( @atrick )
Testing: Added test that the move-only address checker previously miscompiled.
Resolves: rdar://111356251