[llvm] Add a pass to collect dropped var stats for MIR (PR #120780)

[NAKAMURA Takumi via llvm-commits]

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@@ -0,0 +1,70 @@
+///===- DroppedVariableStatsMIR.h - Opt Diagnostics -*- C++ -*-------------===//
+///
+/// Part of the LLVM Project, under the Apache License v2.0 with LLVM
+/// Exceptions. See https://llvm.org/LICENSE.txt for license information.
+/// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+///
+///===---------------------------------------------------------------------===//
+/// \file
+/// Dropped Variable Statistics for Debug Information. Reports any number
+/// of DBG_VALUEs that get dropped due to an optimization pass.
+///
+///===---------------------------------------------------------------------===//
+
+#ifndef LLVM_CODEGEN_DROPPEDVARIABLESTATSMIR_H
+#define LLVM_CODEGEN_DROPPEDVARIABLESTATSMIR_H
+
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/Passes/DroppedVariableStats.h"
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chapuni wrote:

It's odd to depend on LLVMPasses here.

https://github.com/llvm/llvm-project/pull/120780