[4.0] KeyPaths: Pointer-align pointer fields within key path patterns. #10420
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To get the full benefit of dyld3 on Darwin platforms, pointer relocations need to be pointer-aligned, which unfortunately requires growing some key path data structures a little bit. This does tidy up some code that had to hack around our lack of unaligned load/store operations on UnsafeRawPointer, at least. While we're here, we can also simplify the identification strategy for reabstracted stored properties; we only need the property index to identify, not the absolute offset. rdar://problem/32318829
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@swift-ci Please test |
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@slavapestov Mind looking over this for 4.0? |
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LGTM |
slavapestov
approved these changes
Jun 21, 2017
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Explanation: To get the full benefit of dyld3 on Darwin platforms, pointer relocations need to be pointer-aligned. The key path implementation originally packed pointers in order to save memory.
Scope: Any code using literal key path objects would raise "pointer not aligned" linker warnings in Xcode 9.
Issue: rdar://problem/32318829
Risk: Low, incremental change to new feature whose potential fallout should be isolated to key paths.
Testing: Swift CI