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

[Matt Arsenault via llvm-commits]

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@@ -20156,7 +20156,8 @@ void ARMTargetLowering::computeKnownBitsForTargetNode(const SDValue Op,
     // CSNEG: KnownOp0 or KnownOp1 * -1
     if (Op.getOpcode() == ARMISD::CSINC)
       KnownOp1 = KnownBits::computeForAddSub(
-          true, false, KnownOp1, KnownBits::makeConstant(APInt(32, 1)));
+          /*Add*/ true, /*NSW*/ false, /*NUW*/ false, KnownOp1,
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arsenm wrote:

```suggestion
          /*Add=*/ true, /*NSW=*/ false, /*NUW=*/ false, KnownOp1,
```

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