[PATCH] D143287: [Clang][x86] Change x86 cast intrinsics to use __builtin_nondeterministic_value

Mon Feb 6 14:35:30 PST 2023

craig.topper added a comment.

In D143287#4107439 <https://reviews.llvm.org/D143287#4107439>, @ManuelJBrito wrote:

> In D143287#4103597 <https://reviews.llvm.org/D143287#4103597>, @craig.topper wrote:
>
>> We have a couple bugs that show (freeze (poison)) doesn't work past SelectionDAG. Is that a concern here? The most recent https://github.com/llvm/llvm-project/issues/60429
>
> I don't think it's a concern . Here https://godbolt.org/z/1ecM8roYh the lowering seems ok.

The bugs start occurring if you use the same nondeterministic value multiple times and expect the value to be the same for all uses.

Repository:
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CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D143287/new/

https://reviews.llvm.org/D143287