[llvm] [DAG] isKnownToBeAPowerOfTwo - add DemandedElts + OrZero handling to … (PR #181753)

[Simon Pilgrim via llvm-commits]

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@@ -912,6 +913,43 @@ TEST_F(AArch64SelectionDAGTest, KnownToBeAPowerOfTwo_Constants) {
   EXPECT_TRUE(DAG->isKnownToBeAPowerOfTwo(Splat4, /*OrZero=*/true));
   EXPECT_FALSE(DAG->isKnownToBeAPowerOfTwo(SplatBig));
   EXPECT_TRUE(DAG->isKnownToBeAPowerOfTwo(SplatBig, /*OrZero=*/true));
+
+  auto Cond = DAG->getCopyFromReg(DAG->getEntryNode(), Loc, 1, MVT::i1);
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RKSimon wrote:

Start a new unit test KnownToBeAPowerOfTwo_Select

https://github.com/llvm/llvm-project/pull/181753