[llvm] [ADT] Add TrieRawHashMap (PR #69528)

[Aman LaChapelle via llvm-commits]

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@@ -0,0 +1,88 @@
+//===- TrieHashIndexGenerator.h ---------------------------------*- 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIB_SUPPORT_TRIEHASHINDEXGENERATOR_H
+#define LLVM_LIB_SUPPORT_TRIEHASHINDEXGENERATOR_H
+
+#include "llvm/ADT/ArrayRef.h"
+#include <optional>
+
+namespace llvm {
+
+struct IndexGenerator {
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bzcheeseman wrote:

nit: Could you add comments to this struct and its functions? It also may be worth moving them out-of-line, they are maybe a little long to be fully inlined.

https://github.com/llvm/llvm-project/pull/69528