[llvm] [CodeGen] Introduce Static Data Splitter pass (PR #122183)

[Snehasish Kumar via llvm-commits]

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@@ -0,0 +1,154 @@
+//===- StaticDataSplitter.cpp ---------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This pass uses profile information to partition static data sections into
+// hot and cold ones. It begins to split jump tables based on profile, and
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snehasish wrote:

Instead of "It begins... internal data." maybe have a short bullet list like "The pass uses branch profile data to assign hotness based section qualifiers for the following types of static data:
* Jump Tables
* Constant pools (TODO)
* Constant strings (TODO)
* Other module internal data (TODO)"

Then we can update the TODOs as we go along.

https://github.com/llvm/llvm-project/pull/122183