[libc] [llvm] [llvm] Add KnownBits implementations for avgFloor and avgCeil (PR #86445)

[Jay Foad via llvm-commits]

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@@ -501,6 +501,18 @@ TEST(KnownBitsTest, BinaryExhaustive) {
       "mulhu", KnownBits::mulhu,
       [](const APInt &N1, const APInt &N2) { return APIntOps::mulhu(N1, N2); },
       /*CheckOptimality=*/false);
+
+  testBinaryOpExhaustive("avgFloorS", KnownBits::avgFloorS, APIntOps::avgFloorS,
+                         false);
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jayfoad wrote:

I don't think you need `false` here because the knownbits implementation should be optimal.

https://github.com/llvm/llvm-project/pull/86445