[llvm] [MacroFusion] Support commutable instructions (PR #82751)

[Pengcheng Wang via llvm-commits]

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@@ -78,7 +88,7 @@ def TestFusion: SimpleFusion<"test-fusion", "HasTestFusion", "Test Fusion",
 // CHECK-PREDICATOR-NEXT:    }
 // CHECK-PREDICATOR-NEXT:    return true;
 // CHECK-PREDICATOR-NEXT:  }
-// CHECK-PREDICATOR-NEXT:  bool isTestFusion(
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wangpc-pp wrote:

Which part of `scheduleAdjacentImpl` will create a NewMI?

https://github.com/llvm/llvm-project/pull/82751