[llvm] [AMDGPU]: Add support to unpack V_PK_MOV_B32 (PR #163464)

[Matt Arsenault via llvm-commits]

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@@ -59,7 +59,7 @@ class SIPreEmitPeephole {
   // v_fma_f32 v1, v0, v2, v2
   // Here, we have overwritten v0 before we use it. This function checks if
   // unpacking can lead to such a situation.
-  bool canUnpackingClobberRegister(const MachineInstr &MI);
+  bool canUnpackingClobberRegister(MachineInstr &MI);
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arsenm wrote:

This should stay const 

https://github.com/llvm/llvm-project/pull/163464