[compiler-rt] [compiler-rt] Improve lit test discovery speed on Darwin (PR #195193)

[Andrew Haberlandt via llvm-commits]

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@@ -334,3 +335,22 @@ def build_invocation(compile_flags, with_lto=False):
 
 if config.target_os == "NetBSD":
     config.substitutions.insert(0, ("%run", config.netbsd_noaslr_prefix))
+
+if config.target_os == "Darwin":
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ndrewh wrote:

The problem is not multiple processes, the problem is that we want to memoize across test suites, and each test-suite has its own copy of every function because of the `exec`. The module cache is, however, shared, so I've put a memoized command-runner function into llvm-lit here: https://github.com/llvm/llvm-project/pull/195888

https://github.com/llvm/llvm-project/pull/195193