[compiler-rt] [ctxprof] Auto root detection: trie for stack samples (PR #133106)

[Snehasish Kumar via llvm-commits]

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@@ -0,0 +1,90 @@
+//===- RootAutodetector.cpp - detect contextual profiling roots -----------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "RootAutoDetector.h"
+#include "CtxInstrProfiling.h"
+
+#include "sanitizer_common/sanitizer_common.h"
+#include "sanitizer_common/sanitizer_mutex.h"
+#include "sanitizer_common/sanitizer_placement_new.h"
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snehasish wrote:

I didn't see a usage of placement new in this PR?

https://github.com/llvm/llvm-project/pull/133106