[llvm] [PeepholeOptimizer] Add REG_SEQUENCE subregister use folding (PR #205795)

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github-actions[bot] wrote:

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:warning: Python code formatter, darker found issues in your code. :warning:

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You can test this locally with the following command:
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``````````bash
darker --check --diff -r origin/main...HEAD llvm/utils/git/code-format-helper.py
``````````

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``````````diff
--- code-format-helper.py	2026-06-26 14:49:58.000000 +0000
+++ code-format-helper.py	2026-06-26 15:09:52.330328 +0000
@@ -429,11 +429,15 @@
             # easy to do.
             if filename.endswith(".ll"):
                 try:
                     with open(filename, "r") as f:
                         first_line = f.readline()
-                        if re.search(r"NOTE:.*autogenerated.*update_mir_test_checks", first_line, re.IGNORECASE):
+                        if re.search(
+                            r"NOTE:.*autogenerated.*update_mir_test_checks",
+                            first_line,
+                            re.IGNORECASE,
+                        ):
                             continue
                 except (FileNotFoundError, IOError):
                     continue
 
             if filename.endswith(".ll"):

``````````

</details>


https://github.com/llvm/llvm-project/pull/205795