[llvm] [AMDGPU] Improve combining on v_ldexp (PR #190236)

[Shilei Tian via llvm-commits]

================
@@ -18,19 +18,21 @@
 #include "GCNSubtarget.h"
 #include "llvm/CodeGen/GlobalISel/Combiner.h"
 #include "llvm/CodeGen/GlobalISel/CombinerHelper.h"
+#include "llvm/CodeGen/MachineUniformityAnalysis.h"
 
 namespace llvm {
 class AMDGPUCombinerHelper : public CombinerHelper {
 protected:
   const GCNSubtarget &STI;
   const SIInstrInfo &TII;
+  MachineUniformityInfo *MUI;
----------------
shiltian wrote:

```suggestion
  MachineUniformityInfo *MUI = nullptr;
```

https://github.com/llvm/llvm-project/pull/190236