[clang] [Clang][CMake] Support perf, LBR, and Instrument CLANG_BOLT options (PR #69133)

[Petr Hosek via cfe-commits]

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@@ -6,15 +6,52 @@ import lit.util
 import os
 import subprocess
 
-config.clang = os.path.realpath(lit.util.which('clang-bolt.inst', config.clang_tools_dir)).replace('\\', '/')
+clang_binary = "clang"
+perf_wrapper = ""
+if config.clang_bolt_mode.lower() == "instrument":
+    clang_binary = config.clang_bolt_name
+else:  # perf or LBR
+    perf_wrapper = "%s %s/perf-helper.py perf" % (
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petrhosek wrote:

Please use Python f-string.

https://github.com/llvm/llvm-project/pull/69133