[llvm] [AMDGPU] Implement vop3p complex pattern optmization for gisel (PR #130234)

[Shilei Tian via llvm-commits]

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@@ -4293,44 +4293,350 @@ AMDGPUInstructionSelector::selectVOP3NoMods(MachineOperand &Root) const {
   }};
 }
 
-std::pair<Register, unsigned>
-AMDGPUInstructionSelector::selectVOP3PModsImpl(
-  Register Src, const MachineRegisterInfo &MRI, bool IsDOT) const {
-  unsigned Mods = 0;
-  MachineInstr *MI = MRI.getVRegDef(Src);
+enum srcStatus {
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shiltian wrote:

```suggestion
enum SrcStatus {
```

https://github.com/llvm/llvm-project/pull/130234