[llvm] [AMDGPU] MCExpr printing helper with KnownBits support (PR #95951)

[Pierre van Houtryve via llvm-commits]

================
@@ -303,3 +305,360 @@ const AMDGPUMCExpr *AMDGPUMCExpr::createOccupancy(unsigned InitOcc,
                  CreateExpr(InitOcc), NumSGPRs, NumVGPRs},
                 Ctx);
 }
+
+static KnownBits fromOptionalToKnownBits(std::optional<bool> CompareResult) {
+  const unsigned BitWidth = 64;
----------------
Pierre-vh wrote:

```suggestion
  static constexpr unsigned BitWidth = 64;
```

https://github.com/llvm/llvm-project/pull/95951