[llvm] [WIP]AMDGPU/GlobalISel: Gracefully report regbanklegalize errors (PR #169511)

[Matt Arsenault via llvm-commits]

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@@ -27,11 +30,14 @@ namespace AMDGPU {
 // to replace instruction. In other case InstApplyMethod will create new
 // instruction(s).
 class RegBankLegalizeHelper {
+  MachineFunction &MF;
   const GCNSubtarget &ST;
   MachineIRBuilder &B;
   MachineRegisterInfo &MRI;
   const MachineUniformityInfo &MUI;
   const RegisterBankInfo &RBI;
+  const TargetPassConfig &TPC;
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arsenm wrote:

Probably shouldn't be spreading this, it doesn't exist in new pm 

https://github.com/llvm/llvm-project/pull/169511