[compiler-rt] compiler-rt: Make the tests pass on AArch64 and with page size != 4096. (PR #153860)

[Peter Collingbourne via llvm-commits]

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@@ -965,6 +965,16 @@ def is_windows_lto_supported():
 else:
     config.available_features.add("memprof-shadow-scale-3")
 
+def target_page_size():
+    try:
+        proc = subprocess.Popen(f"{emulator or ""} python3", shell=True, stdin=subprocess.PIPE, stdout=subprocess.PIPE)
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pcc wrote:

I think there's some flexibility in what `emulator` is allowed to be. It could be something like `ssh foo` which means that the shell needs to split `ssh` and `foo`. And then in that case the shell quoting rules end up messing up arguments with spaces (the arguments to ssh get joined together with `" "` and passed as a single argument to `sh -c` so part of the Python script is interpreted by the shell as a shell command). If we want something that works with and without ssh it seemed the simplest way was to pass the script via stdin.

https://github.com/llvm/llvm-project/pull/153860