[llvm-dev] Hoisting in the presence of volatile loads.

[Krzysztof Parzyszek via llvm-dev]

On 12/20/2017 1:37 PM, Sanjoy Das wrote:>
> Fwiw, I was under the impression that regular loads could *not* be
> reordered with volatile loads since we could have e.g.:
> 
>    int *normal = &global_variable;
>    volatile int* ptr = 0;
>    int k = *ptr; // segfaults, and the signal handler writes to *normal
>    int value = *normal;
> 
> and that we'd have to treat volatile loads and stores essentially as
> calls to unknown functions.

For this to work, "normal" should be volatile as well.

-Krzysztof

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