[llvm] [KnownBits] Make nuw and nsw support in computeForAddSub optimal (PR #83382)

[via llvm-commits]

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@@ -166,44 +166,82 @@ TEST(KnownBitsTest, AddCarryExhaustive) {
 }
 
 static void TestAddSubExhaustive(bool IsAdd) {
-  unsigned Bits = 4;
+  unsigned Bits = 6;
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goldsteinn wrote:

Ah, didn't mean to leave that in.

https://github.com/llvm/llvm-project/pull/83382