[llvm] [InstCombine] Add missing patterns for scmp and ucmp (PR #149225)

[Yingwei Zheng via llvm-commits]

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@@ -3757,6 +3757,10 @@ static Instruction *foldBitCeil(SelectInst &SI, IRBuilderBase &Builder,
 //   (x < y) ? -1 : zext(x > y)
 //   (x > y) ? 1 : sext(x != y)
 //   (x > y) ? 1 : sext(x < y)
+//   (x == y) ? 0 : (x > y ? 1 : -1)
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dtcxzyw wrote:

Can you please add some commuted tests?
```
(x != y) ? (x > y ? 1 : -1) : 0
x != C ? (x > C - 1 ? 1 : -1) : 0
```

https://github.com/llvm/llvm-project/pull/149225