[llvm] [DebugInfo][RegisterCoalescer] Drop DBG_VALUEs with unsupported register class (PR #143132)

[Matt Arsenault via llvm-commits]

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@@ -118,28 +118,44 @@ MachineRegisterInfo::constrainRegAttrs(Register Reg,
   return true;
 }
 
-bool
+std::pair<bool, SmallVector<MachineInstr *, 8>>
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arsenm wrote:

First you should not change this function in any way 

https://github.com/llvm/llvm-project/pull/143132