[llvm] [IR] Add disjoint flag for Or instructions. (PR #72583)

[Philip Reames via llvm-commits]

preames wrote:

I'm seeing a downstream assertion failure building SPEC which I suspect is triggered by this change.

```
LoopVectorize.cpp:1122: llvm::InnerLoopVectorizer::collectPoisonGeneratingRecip
es(llvm::VPTransformState&)::<lambda(llvm::VPRecipeBase*)>: Assertion `(!Instr || !Instr->hasPoisonGeneratingFlags()) && "found inst
ruction with poison generating flags not covered by " "VPRecipeWithIRFlags"' failed.
```
I can reduce a test case if needed, but the assertion failure seems fairly self explanatory.  


https://github.com/llvm/llvm-project/pull/72583