[llvm] [MachineSSAUpdater][AMDGPU] Add faster version of MachineSSAUpdater class. (PR #145722)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,78 @@
+//===- MachineSSAUpdaterBulk.h - Unstructured SSA Update Tool ----------*- C++
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arsenm wrote:

Actual file name doesn't match, shouldn't use "2" 

https://github.com/llvm/llvm-project/pull/145722