[PATCH] D53184: [LangRef] Clarify semantics of volatile operations.

[JF Bastien via Phabricator via llvm-commits]

jfb added inline comments.


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Comment at: llvm/trunk/docs/LangRef.rst:2196
+may not modify any other memory accessible by the module being compiled.
+A volatile operation may not call any code in the current module.
+
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Sorry for missing the initial discussion. This disallows using `mmap` to map the same physical memory into two different virtual addresses in the same process. In C++ `volatile` loads and stores exist to denote "external modifications", where "external" is w.r.t. the abstract machine. It seems like a misstep to say that "A volatile operation may not modify any other memory accessible by the module being compiled."


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  https://reviews.llvm.org/D53184/new/

https://reviews.llvm.org/D53184