[llvm] [InstCombine] Explicitly set disjoint flag when converting xor to or. (PR #74229)

[Nikita Popov via llvm-commits]

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@@ -4462,8 +4462,11 @@ Instruction *InstCombinerImpl::visitXor(BinaryOperator &I) {
   Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
   Value *M;
   if (match(&I, m_c_Xor(m_c_And(m_Not(m_Value(M)), m_Value()),
-                        m_c_And(m_Deferred(M), m_Value()))))
-    return BinaryOperator::CreateOr(Op0, Op1);
+                        m_c_And(m_Deferred(M), m_Value())))) {
+    auto *Or = BinaryOperator::CreateOr(Op0, Op1);
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nikic wrote:

We should add a `BinaryOperator::CreateDisjointOr` API, similar to how we have `CreateNUWAdd` and so on.

https://github.com/llvm/llvm-project/pull/74229