[clang] [CIR] Add bit reverse and byte reverse operations (PR #147200)

[Sirui Mu via cfe-commits]

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@@ -2661,6 +2661,55 @@ def BitPopcountOp : CIR_BitOpBase<"bit.popcnt",
   }];
 }
 
+def BitReverseOp : CIR_BitOpBase<"bit.reverse", CIR_UIntOfWidths<[8, 16, 32, 64]>> {
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Lancern wrote:

Well I think we need to think about what the exact scope of `CIR_BitOpBase` is and whether the bit reverse operation should be one of it. I'm naming it `bit.reverse` because I think it should follow the `CIR_BitOpBase` convention.

https://github.com/llvm/llvm-project/pull/147200