[llvm] [AMDGPU] Add iglp_opt(3) for simple mfma / exp interleaving (PR #117269)

[Austin Kerbow via llvm-commits]

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@@ -1845,6 +1846,50 @@ bool MFMAExpInterleaveOpt::applyIGLPStrategy(
   return true;
 }
 
+class MFMAExpSimpleInterleaveOpt final : public IGLPStrategy {
+private:
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kerbowa wrote:

NIT: remove `private:`

https://github.com/llvm/llvm-project/pull/117269