[PATCH] D95238: [LangRef] Update memory access ops to raise UB if ptrs are not well defined

[Johannes Doerfert via Phabricator via llvm-commits]

jdoerfert added a comment.

+1 on the motivation. When we landed the other patch we didn't consider all the implications and, so far, they clearly outweigh the benefits of having partial undef offsets "work".

LGTM. Someone else?



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Comment at: llvm/docs/LangRef.rst:12697
+If ``<len>`` is 0, the pointers may be NULL, dangling, ``undef``, or ``poison``
 pointers. However, they must still be appropriately aligned.
+If ``<len>`` is not a well-defined value, the behavior is undefined.
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Partially related: I never understood the alignment thing. `undef` and `poison` are not aligned. Violating `align` should result in a `poison` value, which we had in the first place. We should check why this is her.


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https://reviews.llvm.org/D95238