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

[Nikita Popov via llvm-commits]

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@@ -252,8 +255,11 @@ Value *InstCombinerImpl::SimplifyDemandedUseBits(Value *V, APInt DemandedMask,
       return I->getOperand(1);
 
     // If the RHS is a constant, see if we can simplify it.
-    if (ShrinkDemandedConstant(I, 1, DemandedMask))
+    if (ShrinkDemandedConstant(I, 1, DemandedMask)) {
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nikic wrote:

As long as this sticks with shrinking only, we shouldn't have to drop flags here. (It can only get "more" disjoint.)

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