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

[Jay Foad 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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jayfoad wrote:

Remove this change? I tend to increase it for local testing, but I don't think it actually needs to be any higher than about 3 or 4 for full test coverage.

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