[llvm] [Instrumentor] Add Instrumentor pass (PR #138958)

[Shilei Tian via llvm-commits]

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@@ -0,0 +1,739 @@
+//===- Transforms/IPO/Instrumentor.h --------------------------===//
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shiltian wrote:

not 80 chars wide

https://github.com/llvm/llvm-project/pull/138958